| /* vi: set sw=4 ts=4: */ |
| /* |
| * A prototype Bourne shell grammar parser. |
| * Intended to follow the original Thompson and Ritchie |
| * "small and simple is beautiful" philosophy, which |
| * incidentally is a good match to today's BusyBox. |
| * |
| * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org> |
| * Copyright (C) 2008,2009 Denys Vlasenko <vda.linux@googlemail.com> |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| * |
| * Credits: |
| * The parser routines proper are all original material, first |
| * written Dec 2000 and Jan 2001 by Larry Doolittle. The |
| * execution engine, the builtins, and much of the underlying |
| * support has been adapted from busybox-0.49pre's lash, which is |
| * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
| * written by Erik Andersen <andersen@codepoet.org>. That, in turn, |
| * is based in part on ladsh.c, by Michael K. Johnson and Erik W. |
| * Troan, which they placed in the public domain. I don't know |
| * how much of the Johnson/Troan code has survived the repeated |
| * rewrites. |
| * |
| * Other credits: |
| * o_addchr derived from similar w_addchar function in glibc-2.2. |
| * parse_redirect, redirect_opt_num, and big chunks of main |
| * and many builtins derived from contributions by Erik Andersen. |
| * Miscellaneous bugfixes from Matt Kraai. |
| * |
| * There are two big (and related) architecture differences between |
| * this parser and the lash parser. One is that this version is |
| * actually designed from the ground up to understand nearly all |
| * of the Bourne grammar. The second, consequential change is that |
| * the parser and input reader have been turned inside out. Now, |
| * the parser is in control, and asks for input as needed. The old |
| * way had the input reader in control, and it asked for parsing to |
| * take place as needed. The new way makes it much easier to properly |
| * handle the recursion implicit in the various substitutions, especially |
| * across continuation lines. |
| * |
| * TODOs: |
| * grep for "TODO" and fix (some of them are easy) |
| * make complex ${var%...} constructs support optional |
| * make here documents optional |
| * special variables (done: PWD, PPID, RANDOM) |
| * follow IFS rules more precisely, including update semantics |
| * tilde expansion |
| * aliases |
| * "command" missing features: |
| * command -p CMD: run CMD using default $PATH |
| * (can use this to override standalone shell as well?) |
| * command BLTIN: disables special-ness (e.g. errors do not abort) |
| * command -V CMD1 CMD2 CMD3 (multiple args) (not in standard) |
| * builtins mandated by standards we don't support: |
| * [un]alias, fc: |
| * fc -l[nr] [BEG] [END]: list range of commands in history |
| * fc [-e EDITOR] [BEG] [END]: edit/rerun range of commands |
| * fc -s [PAT=REP] [CMD]: rerun CMD, replacing PAT with REP |
| * |
| * Bash compat TODO: |
| * redirection of stdout+stderr: &> and >& |
| * reserved words: function select |
| * advanced test: [[ ]] |
| * process substitution: <(list) and >(list) |
| * let EXPR [EXPR...] |
| * Each EXPR is an arithmetic expression (ARITHMETIC EVALUATION) |
| * If the last arg evaluates to 0, let returns 1; 0 otherwise. |
| * NB: let `echo 'a=a + 1'` - error (IOW: multi-word expansion is used) |
| * ((EXPR)) |
| * The EXPR is evaluated according to ARITHMETIC EVALUATION. |
| * This is exactly equivalent to let "EXPR". |
| * $[EXPR]: synonym for $((EXPR)) |
| * indirect expansion: ${!VAR} |
| * substring op on @: ${@:n:m} |
| * |
| * Won't do: |
| * Some builtins mandated by standards: |
| * newgrp [GRP]: not a builtin in bash but a suid binary |
| * which spawns a new shell with new group ID |
| * |
| * Status of [[ support: |
| * [[ args ]] are CMD_SINGLEWORD_NOGLOB: |
| * v='a b'; [[ $v = 'a b' ]]; echo 0:$? |
| * [[ /bin/n* ]]; echo 0:$? |
| * = is glob match operator, not equality operator: STR = GLOB |
| * == same as = |
| * =~ is regex match operator: STR =~ REGEX |
| * TODO: |
| * quoting needs to be considered (-f is an operator, "-f" and ""-f are not; etc) |
| * in word = GLOB, quoting should be significant on char-by-char basis: a*cd"*" |
| */ |
| //config:config HUSH |
| //config: bool "hush (68 kb)" |
| //config: default y |
| //config: select SHELL_HUSH |
| //config: help |
| //config: hush is a small shell. It handles the normal flow control |
| //config: constructs such as if/then/elif/else/fi, for/in/do/done, while loops, |
| //config: case/esac. Redirections, here documents, $((arithmetic)) |
| //config: and functions are supported. |
| //config: |
| //config: It will compile and work on no-mmu systems. |
| //config: |
| //config: It does not handle select, aliases, tilde expansion, |
| //config: &>file and >&file redirection of stdout+stderr. |
| //config: |
| // This option is visible (has a description) to make it possible to select |
| // a "scripted" applet (such as NOLOGIN) but avoid selecting any shells: |
| //config:config SHELL_HUSH |
| //config: bool "Internal shell for embedded script support" |
| //config: default n |
| //config: |
| //config:# hush options |
| //config:# It's only needed to get "nice" menuconfig indenting. |
| //config:if SHELL_HUSH || HUSH || SH_IS_HUSH || BASH_IS_HUSH |
| //config: |
| //config:config HUSH_BASH_COMPAT |
| //config: bool "bash-compatible extensions" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_BRACE_EXPANSION |
| //config: bool "Brace expansion" |
| //config: default y |
| //config: depends on HUSH_BASH_COMPAT |
| //config: help |
| //config: Enable {abc,def} extension. |
| //config: |
| //config:config HUSH_BASH_SOURCE_CURDIR |
| //config: bool "'source' and '.' builtins search current directory after $PATH" |
| //config: default n # do not encourage non-standard behavior |
| //config: depends on HUSH_BASH_COMPAT |
| //config: help |
| //config: This is not compliant with standards. Avoid if possible. |
| //config: |
| //config:config HUSH_LINENO_VAR |
| //config: bool "$LINENO variable (bashism)" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_INTERACTIVE |
| //config: bool "Interactive mode" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable interactive mode (prompt and command editing). |
| //config: Without this, hush simply reads and executes commands |
| //config: from stdin just like a shell script from a file. |
| //config: No prompt, no PS1/PS2 magic shell variables. |
| //config: |
| //config:config HUSH_SAVEHISTORY |
| //config: bool "Save command history to .hush_history" |
| //config: default y |
| //config: depends on HUSH_INTERACTIVE && FEATURE_EDITING_SAVEHISTORY |
| //config: |
| //config:config HUSH_JOB |
| //config: bool "Job control" |
| //config: default y |
| //config: depends on HUSH_INTERACTIVE |
| //config: help |
| //config: Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current |
| //config: command (not entire shell), fg/bg builtins work. Without this option, |
| //config: "cmd &" still works by simply spawning a process and immediately |
| //config: prompting for next command (or executing next command in a script), |
| //config: but no separate process group is formed. |
| //config: |
| //config:config HUSH_TICK |
| //config: bool "Support command substitution" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable `command` and $(command). |
| //config: |
| //config:config HUSH_IF |
| //config: bool "Support if/then/elif/else/fi" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_LOOPS |
| //config: bool "Support for, while and until loops" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_CASE |
| //config: bool "Support case ... esac statement" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable case ... esac statement. +400 bytes. |
| //config: |
| //config:config HUSH_FUNCTIONS |
| //config: bool "Support funcname() { commands; } syntax" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable support for shell functions. +800 bytes. |
| //config: |
| //config:config HUSH_LOCAL |
| //config: bool "local builtin" |
| //config: default y |
| //config: depends on HUSH_FUNCTIONS |
| //config: help |
| //config: Enable support for local variables in functions. |
| //config: |
| //config:config HUSH_RANDOM_SUPPORT |
| //config: bool "Pseudorandom generator and $RANDOM variable" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable pseudorandom generator and dynamic variable "$RANDOM". |
| //config: Each read of "$RANDOM" will generate a new pseudorandom value. |
| //config: |
| //config:config HUSH_MODE_X |
| //config: bool "Support 'hush -x' option and 'set -x' command" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: This instructs hush to print commands before execution. |
| //config: Adds ~300 bytes. |
| //config: |
| //config:config HUSH_ECHO |
| //config: bool "echo builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_PRINTF |
| //config: bool "printf builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_TEST |
| //config: bool "test builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_HELP |
| //config: bool "help builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_EXPORT |
| //config: bool "export builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_EXPORT_N |
| //config: bool "Support 'export -n' option" |
| //config: default y |
| //config: depends on HUSH_EXPORT |
| //config: help |
| //config: export -n unexports variables. It is a bash extension. |
| //config: |
| //config:config HUSH_READONLY |
| //config: bool "readonly builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: help |
| //config: Enable support for read-only variables. |
| //config: |
| //config:config HUSH_KILL |
| //config: bool "kill builtin (supports kill %jobspec)" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_WAIT |
| //config: bool "wait builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_COMMAND |
| //config: bool "command builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_TRAP |
| //config: bool "trap builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_TYPE |
| //config: bool "type builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_TIMES |
| //config: bool "times builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_READ |
| //config: bool "read builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_SET |
| //config: bool "set builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_UNSET |
| //config: bool "unset builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_ULIMIT |
| //config: bool "ulimit builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_UMASK |
| //config: bool "umask builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_GETOPTS |
| //config: bool "getopts builtin" |
| //config: default y |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:config HUSH_MEMLEAK |
| //config: bool "memleak builtin (debugging)" |
| //config: default n |
| //config: depends on SHELL_HUSH |
| //config: |
| //config:endif # hush options |
| |
| //applet:IF_HUSH(APPLET(hush, BB_DIR_BIN, BB_SUID_DROP)) |
| // APPLET_ODDNAME:name main location suid_type help |
| //applet:IF_SH_IS_HUSH( APPLET_ODDNAME(sh, hush, BB_DIR_BIN, BB_SUID_DROP, hush)) |
| //applet:IF_BASH_IS_HUSH(APPLET_ODDNAME(bash, hush, BB_DIR_BIN, BB_SUID_DROP, hush)) |
| |
| //kbuild:lib-$(CONFIG_SHELL_HUSH) += hush.o match.o shell_common.o |
| //kbuild:lib-$(CONFIG_HUSH_RANDOM_SUPPORT) += random.o |
| |
| /* -i (interactive) is also accepted, |
| * but does nothing, therefore not shown in help. |
| * NOMMU-specific options are not meant to be used by users, |
| * therefore we don't show them either. |
| */ |
| //usage:#define hush_trivial_usage |
| //usage: "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE ARGS | -s ARGS]" |
| //usage:#define hush_full_usage "\n\n" |
| //usage: "Unix shell interpreter" |
| |
| #if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \ |
| || defined(__APPLE__) \ |
| ) |
| # include <malloc.h> /* for malloc_trim */ |
| #endif |
| #include <glob.h> |
| /* #include <dmalloc.h> */ |
| #if ENABLE_HUSH_CASE |
| # include <fnmatch.h> |
| #endif |
| #include <sys/times.h> |
| #include <sys/utsname.h> /* for setting $HOSTNAME */ |
| |
| #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */ |
| #include "unicode.h" |
| #include "shell_common.h" |
| #include "math.h" |
| #include "match.h" |
| #if ENABLE_HUSH_RANDOM_SUPPORT |
| # include "random.h" |
| #else |
| # define CLEAR_RANDOM_T(rnd) ((void)0) |
| #endif |
| #ifndef O_CLOEXEC |
| # define O_CLOEXEC 0 |
| #endif |
| #ifndef F_DUPFD_CLOEXEC |
| # define F_DUPFD_CLOEXEC F_DUPFD |
| #endif |
| |
| #if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !ENABLE_SHELL_ASH |
| # include "embedded_scripts.h" |
| #else |
| # define NUM_SCRIPTS 0 |
| #endif |
| |
| /* So far, all bash compat is controlled by one config option */ |
| /* Separate defines document which part of code implements what */ |
| #define BASH_PATTERN_SUBST ENABLE_HUSH_BASH_COMPAT |
| #define BASH_SUBSTR ENABLE_HUSH_BASH_COMPAT |
| #define BASH_SOURCE ENABLE_HUSH_BASH_COMPAT |
| #define BASH_DOLLAR_SQUOTE ENABLE_HUSH_BASH_COMPAT |
| #define BASH_HOSTNAME_VAR ENABLE_HUSH_BASH_COMPAT |
| #define BASH_EPOCH_VARS ENABLE_HUSH_BASH_COMPAT |
| #define BASH_TEST2 (ENABLE_HUSH_BASH_COMPAT && ENABLE_HUSH_TEST) |
| #define BASH_READ_D ENABLE_HUSH_BASH_COMPAT |
| |
| |
| /* Build knobs */ |
| #define LEAK_HUNTING 0 |
| #define BUILD_AS_NOMMU 0 |
| /* Enable/disable sanity checks. Ok to enable in production, |
| * only adds a bit of bloat. Set to >1 to get non-production level verbosity. |
| * Keeping 1 for now even in released versions. |
| */ |
| #define HUSH_DEBUG 1 |
| /* Slightly bigger (+200 bytes), but faster hush. |
| * So far it only enables a trick with counting SIGCHLDs and forks, |
| * which allows us to do fewer waitpid's. |
| * (we can detect a case where neither forks were done nor SIGCHLDs happened |
| * and therefore waitpid will return the same result as last time) |
| */ |
| #define ENABLE_HUSH_FAST 0 |
| /* TODO: implement simplified code for users which do not need ${var%...} ops |
| * So far ${var%...} ops are always enabled: |
| */ |
| #define ENABLE_HUSH_DOLLAR_OPS 1 |
| |
| |
| #if BUILD_AS_NOMMU |
| # undef BB_MMU |
| # undef USE_FOR_NOMMU |
| # undef USE_FOR_MMU |
| # define BB_MMU 0 |
| # define USE_FOR_NOMMU(...) __VA_ARGS__ |
| # define USE_FOR_MMU(...) |
| #endif |
| |
| #include "NUM_APPLETS.h" |
| #if NUM_APPLETS == 1 |
| /* STANDALONE does not make sense, and won't compile */ |
| # undef CONFIG_FEATURE_SH_STANDALONE |
| # undef ENABLE_FEATURE_SH_STANDALONE |
| # undef IF_FEATURE_SH_STANDALONE |
| # undef IF_NOT_FEATURE_SH_STANDALONE |
| # define ENABLE_FEATURE_SH_STANDALONE 0 |
| # define IF_FEATURE_SH_STANDALONE(...) |
| # define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__ |
| #endif |
| |
| #if !ENABLE_HUSH_INTERACTIVE |
| # undef ENABLE_FEATURE_EDITING |
| # define ENABLE_FEATURE_EDITING 0 |
| # undef ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| # define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0 |
| # undef ENABLE_FEATURE_EDITING_SAVE_ON_EXIT |
| # define ENABLE_FEATURE_EDITING_SAVE_ON_EXIT 0 |
| #endif |
| |
| /* Do we support ANY keywords? */ |
| #if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE |
| # define HAS_KEYWORDS 1 |
| # define IF_HAS_KEYWORDS(...) __VA_ARGS__ |
| # define IF_HAS_NO_KEYWORDS(...) |
| #else |
| # define HAS_KEYWORDS 0 |
| # define IF_HAS_KEYWORDS(...) |
| # define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__ |
| #endif |
| |
| /* If you comment out one of these below, it will be #defined later |
| * to perform debug printfs to stderr: */ |
| #define debug_printf(...) do {} while (0) |
| /* Finer-grained debug switches */ |
| #define debug_printf_parse(...) do {} while (0) |
| #define debug_printf_heredoc(...) do {} while (0) |
| #define debug_print_tree(a, b) do {} while (0) |
| #define debug_printf_exec(...) do {} while (0) |
| #define debug_printf_env(...) do {} while (0) |
| #define debug_printf_jobs(...) do {} while (0) |
| #define debug_printf_expand(...) do {} while (0) |
| #define debug_printf_varexp(...) do {} while (0) |
| #define debug_printf_glob(...) do {} while (0) |
| #define debug_printf_redir(...) do {} while (0) |
| #define debug_printf_list(...) do {} while (0) |
| #define debug_printf_subst(...) do {} while (0) |
| #define debug_printf_prompt(...) do {} while (0) |
| #define debug_printf_clean(...) do {} while (0) |
| |
| #define ERR_PTR ((void*)(long)1) |
| |
| #define JOB_STATUS_FORMAT "[%u] %-22s %.40s\n" |
| |
| #define _SPECIAL_VARS_STR "_*@$!?#-" |
| #define SPECIAL_VARS_STR ("_*@$!?#-" + 1) |
| #define NUMERIC_SPECVARS_STR ("_*@$!?#-" + 3) |
| #if BASH_PATTERN_SUBST |
| /* Support / and // replace ops */ |
| /* Note that // is stored as \ in "encoded" string representation */ |
| # define VAR_ENCODED_SUBST_OPS "\\/%#:-=+?" |
| # define VAR_SUBST_OPS ("\\/%#:-=+?" + 1) |
| # define MINUS_PLUS_EQUAL_QUESTION ("\\/%#:-=+?" + 5) |
| #else |
| # define VAR_ENCODED_SUBST_OPS "%#:-=+?" |
| # define VAR_SUBST_OPS "%#:-=+?" |
| # define MINUS_PLUS_EQUAL_QUESTION ("%#:-=+?" + 3) |
| #endif |
| |
| #define SPECIAL_VAR_SYMBOL_STR "\3" |
| #define SPECIAL_VAR_SYMBOL 3 |
| /* The "variable" with name "\1" emits string "\3". Testcase: "echo ^C" */ |
| #define SPECIAL_VAR_QUOTED_SVS 1 |
| |
| struct variable; |
| |
| static const char hush_version_str[] ALIGN1 = "HUSH_VERSION="BB_VER; |
| |
| /* This supports saving pointers malloced in vfork child, |
| * to be freed in the parent. |
| */ |
| #if !BB_MMU |
| typedef struct nommu_save_t { |
| struct variable *old_vars; |
| char **argv; |
| char **argv_from_re_execing; |
| } nommu_save_t; |
| #endif |
| |
| enum { |
| RES_NONE = 0, |
| #if ENABLE_HUSH_IF |
| RES_IF , |
| RES_THEN , |
| RES_ELIF , |
| RES_ELSE , |
| RES_FI , |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| RES_FOR , |
| RES_WHILE , |
| RES_UNTIL , |
| RES_DO , |
| RES_DONE , |
| #endif |
| #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE |
| RES_IN , |
| #endif |
| #if ENABLE_HUSH_CASE |
| RES_CASE , |
| /* three pseudo-keywords support contrived "case" syntax: */ |
| RES_CASE_IN, /* "case ... IN", turns into RES_MATCH when IN is observed */ |
| RES_MATCH , /* "word)" */ |
| RES_CASE_BODY, /* "this command is inside CASE" */ |
| RES_ESAC , |
| #endif |
| RES_XXXX , |
| RES_SNTX |
| }; |
| |
| typedef struct o_string { |
| char *data; |
| int length; /* position where data is appended */ |
| int maxlen; |
| int o_expflags; |
| /* At least some part of the string was inside '' or "", |
| * possibly empty one: word"", wo''rd etc. */ |
| smallint has_quoted_part; |
| smallint has_empty_slot; |
| smallint ended_in_ifs; |
| } o_string; |
| enum { |
| EXP_FLAG_SINGLEWORD = 0x80, /* must be 0x80 */ |
| EXP_FLAG_GLOB = 0x2, |
| /* Protect newly added chars against globbing |
| * by prepending \ to *, ?, [, \ */ |
| EXP_FLAG_ESC_GLOB_CHARS = 0x1, |
| }; |
| /* Used for initialization: o_string foo = NULL_O_STRING; */ |
| #define NULL_O_STRING { NULL } |
| |
| #ifndef debug_printf_parse |
| static const char *const assignment_flag[] = { |
| "MAYBE_ASSIGNMENT", |
| "DEFINITELY_ASSIGNMENT", |
| "NOT_ASSIGNMENT", |
| "WORD_IS_KEYWORD", |
| }; |
| #endif |
| |
| /* We almost can use standard FILE api, but we need an ability to move |
| * its fd when redirects coincide with it. No api exists for that |
| * (RFE for it at https://sourceware.org/bugzilla/show_bug.cgi?id=21902). |
| * HFILE is our internal alternative. Only supports reading. |
| * Since we now can, we incorporate linked list of all opened HFILEs |
| * into the struct (used to be a separate mini-list). |
| */ |
| typedef struct HFILE { |
| char *cur; |
| char *end; |
| struct HFILE *next_hfile; |
| int fd; |
| char buf[1024]; |
| } HFILE; |
| |
| typedef struct in_str { |
| const char *p; |
| int peek_buf[2]; |
| int last_char; |
| HFILE *file; |
| } in_str; |
| |
| /* The descrip member of this structure is only used to make |
| * debugging output pretty */ |
| static const struct { |
| int32_t mode; |
| signed char default_fd; |
| char descrip[3]; |
| } redir_table[] ALIGN4 = { |
| { O_RDONLY, 0, "<" }, |
| { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" }, |
| { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" }, |
| { O_CREAT|O_RDWR, 1, "<>" }, |
| { O_RDONLY, 0, "<<" }, |
| /* Should not be needed. Bogus default_fd helps in debugging */ |
| /* { O_RDONLY, 77, "<<" }, */ |
| }; |
| |
| struct redir_struct { |
| struct redir_struct *next; |
| char *rd_filename; /* filename */ |
| int rd_fd; /* fd to redirect */ |
| /* fd to redirect to, or -3 if rd_fd is to be closed (n>&-) */ |
| int rd_dup; |
| smallint rd_type; /* (enum redir_type) */ |
| /* note: for heredocs, rd_filename contains heredoc delimiter, |
| * and subsequently heredoc itself; and rd_dup is a bitmask: |
| * bit 0: do we need to trim leading tabs? |
| * bit 1: is heredoc quoted (<<'delim' syntax) ? |
| */ |
| }; |
| typedef enum redir_type { |
| REDIRECT_INPUT = 0, |
| REDIRECT_OVERWRITE = 1, |
| REDIRECT_APPEND = 2, |
| REDIRECT_IO = 3, |
| REDIRECT_HEREDOC = 4, |
| REDIRECT_HEREDOC2 = 5, /* REDIRECT_HEREDOC after heredoc is loaded */ |
| |
| REDIRFD_CLOSE = -3, |
| REDIRFD_SYNTAX_ERR = -2, |
| REDIRFD_TO_FILE = -1, |
| /* otherwise, rd_fd is redirected to rd_dup */ |
| |
| HEREDOC_SKIPTABS = 1, |
| HEREDOC_QUOTED = 2, |
| } redir_type; |
| |
| |
| struct command { |
| pid_t pid; /* 0 if exited */ |
| unsigned assignment_cnt; /* how many argv[i] are assignments? */ |
| #if ENABLE_HUSH_LINENO_VAR |
| unsigned lineno; |
| #endif |
| smallint cmd_type; /* CMD_xxx */ |
| #define CMD_NORMAL 0 |
| #define CMD_SUBSHELL 1 |
| #if BASH_TEST2 |
| /* used for "[[ EXPR ]]" */ |
| # define CMD_TEST2_SINGLEWORD_NOGLOB 2 |
| #endif |
| #if BASH_TEST2 || ENABLE_HUSH_LOCAL || ENABLE_HUSH_EXPORT || ENABLE_HUSH_READONLY |
| /* used to prevent word splitting and globbing in "export v=t*" */ |
| # define CMD_SINGLEWORD_NOGLOB 3 |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| # define CMD_FUNCDEF 4 |
| #endif |
| |
| smalluint cmd_exitcode; |
| /* if non-NULL, this "command" is { list }, ( list ), or a compound statement */ |
| struct pipe *group; |
| #if !BB_MMU |
| char *group_as_string; |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| struct function *child_func; |
| /* This field is used to prevent a bug here: |
| * while...do f1() {a;}; f1; f1() {b;}; f1; done |
| * When we execute "f1() {a;}" cmd, we create new function and clear |
| * cmd->group, cmd->group_as_string, cmd->argv[0]. |
| * When we execute "f1() {b;}", we notice that f1 exists, |
| * and that its "parent cmd" struct is still "alive", |
| * we put those fields back into cmd->xxx |
| * (struct function has ->parent_cmd ptr to facilitate that). |
| * When we loop back, we can execute "f1() {a;}" again and set f1 correctly. |
| * Without this trick, loop would execute a;b;b;b;... |
| * instead of correct sequence a;b;a;b;... |
| * When command is freed, it severs the link |
| * (sets ->child_func->parent_cmd to NULL). |
| */ |
| #endif |
| char **argv; /* command name and arguments */ |
| /* argv vector may contain variable references (^Cvar^C, ^C0^C etc) |
| * and on execution these are substituted with their values. |
| * Substitution can make _several_ words out of one argv[n]! |
| * Example: argv[0]=='.^C*^C.' here: echo .$*. |
| * References of the form ^C`cmd arg^C are `cmd arg` substitutions. |
| */ |
| struct redir_struct *redirects; /* I/O redirections */ |
| }; |
| /* Is there anything in this command at all? */ |
| #define IS_NULL_CMD(cmd) \ |
| (!(cmd)->group && !(cmd)->argv && !(cmd)->redirects) |
| |
| struct pipe { |
| struct pipe *next; |
| int num_cmds; /* total number of commands in pipe */ |
| int alive_cmds; /* number of commands running (not exited) */ |
| int stopped_cmds; /* number of commands alive, but stopped */ |
| #if ENABLE_HUSH_JOB |
| unsigned jobid; /* job number */ |
| pid_t pgrp; /* process group ID for the job */ |
| char *cmdtext; /* name of job */ |
| #endif |
| struct command *cmds; /* array of commands in pipe */ |
| smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ |
| IF_HAS_KEYWORDS(smallint pi_inverted;) /* "! cmd | cmd" */ |
| IF_HAS_KEYWORDS(smallint res_word;) /* needed for if, for, while, until... */ |
| }; |
| typedef enum pipe_style { |
| PIPE_SEQ = 0, |
| PIPE_AND = 1, |
| PIPE_OR = 2, |
| PIPE_BG = 3, |
| } pipe_style; |
| /* Is there anything in this pipe at all? */ |
| #define IS_NULL_PIPE(pi) \ |
| ((pi)->num_cmds == 0 IF_HAS_KEYWORDS( && (pi)->res_word == RES_NONE)) |
| |
| /* This holds pointers to the various results of parsing */ |
| struct parse_context { |
| /* linked list of pipes */ |
| struct pipe *list_head; |
| /* last pipe (being constructed right now) */ |
| struct pipe *pipe; |
| /* last command in pipe (being constructed right now) */ |
| struct command *command; |
| /* last redirect in command->redirects list */ |
| struct redir_struct *pending_redirect; |
| o_string word; |
| #if !BB_MMU |
| o_string as_string; |
| #endif |
| smallint is_assignment; /* 0:maybe, 1:yes, 2:no, 3:keyword */ |
| #if HAS_KEYWORDS |
| smallint ctx_res_w; |
| smallint ctx_inverted; /* "! cmd | cmd" */ |
| #if ENABLE_HUSH_CASE |
| smallint ctx_dsemicolon; /* ";;" seen */ |
| #endif |
| /* bitmask of FLAG_xxx, for figuring out valid reserved words */ |
| int old_flag; |
| /* group we are enclosed in: |
| * example: "if pipe1; pipe2; then pipe3; fi" |
| * when we see "if" or "then", we malloc and copy current context, |
| * and make ->stack point to it. then we parse pipeN. |
| * when closing "then" / fi" / whatever is found, |
| * we move list_head into ->stack->command->group, |
| * copy ->stack into current context, and delete ->stack. |
| * (parsing of { list } and ( list ) doesn't use this method) |
| */ |
| struct parse_context *stack; |
| #endif |
| }; |
| enum { |
| MAYBE_ASSIGNMENT = 0, |
| DEFINITELY_ASSIGNMENT = 1, |
| NOT_ASSIGNMENT = 2, |
| /* Not an assignment, but next word may be: "if v=xyz cmd;" */ |
| WORD_IS_KEYWORD = 3, |
| }; |
| |
| /* On program start, environ points to initial environment. |
| * putenv adds new pointers into it, unsetenv removes them. |
| * Neither of these (de)allocates the strings. |
| * setenv allocates new strings in malloc space and does putenv, |
| * and thus setenv is unusable (leaky) for shell's purposes */ |
| #define setenv(...) setenv_is_leaky_dont_use() |
| struct variable { |
| struct variable *next; |
| char *varstr; /* points to "name=" portion */ |
| int max_len; /* if > 0, name is part of initial env; else name is malloced */ |
| uint16_t var_nest_level; |
| smallint flg_export; /* putenv should be done on this var */ |
| smallint flg_read_only; |
| }; |
| |
| enum { |
| BC_BREAK = 1, |
| BC_CONTINUE = 2, |
| }; |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| struct function { |
| struct function *next; |
| char *name; |
| struct command *parent_cmd; |
| struct pipe *body; |
| # if !BB_MMU |
| char *body_as_string; |
| # endif |
| }; |
| #endif |
| |
| |
| /* set -/+o OPT support. (TODO: make it optional) |
| * bash supports the following opts: |
| * allexport off |
| * braceexpand on |
| * emacs on |
| * errexit off |
| * errtrace off |
| * functrace off |
| * hashall on |
| * histexpand off |
| * history on |
| * ignoreeof off |
| * interactive-comments on |
| * keyword off |
| * monitor on |
| * noclobber off |
| * noexec off |
| * noglob off |
| * nolog off |
| * notify off |
| * nounset off |
| * onecmd off |
| * physical off |
| * pipefail off |
| * posix off |
| * privileged off |
| * verbose off |
| * vi off |
| * xtrace off |
| */ |
| static const char o_opt_strings[] ALIGN1 = |
| "pipefail\0" |
| "noexec\0" |
| "errexit\0" |
| #if ENABLE_HUSH_MODE_X |
| "xtrace\0" |
| #endif |
| ; |
| enum { |
| OPT_O_PIPEFAIL, |
| OPT_O_NOEXEC, |
| OPT_O_ERREXIT, |
| #if ENABLE_HUSH_MODE_X |
| OPT_O_XTRACE, |
| #endif |
| NUM_OPT_O |
| }; |
| |
| /* "Globals" within this file */ |
| /* Sorted roughly by size (smaller offsets == smaller code) */ |
| struct globals { |
| /* interactive_fd != 0 means we are an interactive shell. |
| * If we are, then saved_tty_pgrp can also be != 0, meaning |
| * that controlling tty is available. With saved_tty_pgrp == 0, |
| * job control still works, but terminal signals |
| * (^C, ^Z, ^Y, ^\) won't work at all, and background |
| * process groups can only be created with "cmd &". |
| * With saved_tty_pgrp != 0, hush will use tcsetpgrp() |
| * to give tty to the foreground process group, |
| * and will take it back when the group is stopped (^Z) |
| * or killed (^C). |
| */ |
| #if ENABLE_HUSH_INTERACTIVE |
| /* 'interactive_fd' is a fd# open to ctty, if we have one |
| * _AND_ if we decided to act interactively */ |
| int interactive_fd; |
| IF_NOT_FEATURE_EDITING_FANCY_PROMPT(char *PS1;) |
| # define G_interactive_fd (G.interactive_fd) |
| #else |
| # define G_interactive_fd 0 |
| #endif |
| #if ENABLE_FEATURE_EDITING |
| line_input_t *line_input_state; |
| #endif |
| pid_t root_pid; |
| pid_t root_ppid; |
| pid_t last_bg_pid; |
| #if ENABLE_HUSH_RANDOM_SUPPORT |
| random_t random_gen; |
| #endif |
| #if ENABLE_HUSH_JOB |
| int run_list_level; |
| unsigned last_jobid; |
| pid_t saved_tty_pgrp; |
| struct pipe *job_list; |
| # define G_saved_tty_pgrp (G.saved_tty_pgrp) |
| #else |
| # define G_saved_tty_pgrp 0 |
| #endif |
| /* How deeply are we in context where "set -e" is ignored */ |
| int errexit_depth; |
| /* "set -e" rules (do we follow them correctly?): |
| * Exit if pipe, list, or compound command exits with a non-zero status. |
| * Shell does not exit if failed command is part of condition in |
| * if/while, part of && or || list except the last command, any command |
| * in a pipe but the last, or if the command's return value is being |
| * inverted with !. If a compound command other than a subshell returns a |
| * non-zero status because a command failed while -e was being ignored, the |
| * shell does not exit. A trap on ERR, if set, is executed before the shell |
| * exits [ERR is a bashism]. |
| * |
| * If a compound command or function executes in a context where -e is |
| * ignored, none of the commands executed within are affected by the -e |
| * setting. If a compound command or function sets -e while executing in a |
| * context where -e is ignored, that setting does not have any effect until |
| * the compound command or the command containing the function call completes. |
| */ |
| |
| char o_opt[NUM_OPT_O]; |
| #if ENABLE_HUSH_MODE_X |
| # define G_x_mode (G.o_opt[OPT_O_XTRACE]) |
| #else |
| # define G_x_mode 0 |
| #endif |
| char opt_s; |
| char opt_c; |
| #if ENABLE_HUSH_INTERACTIVE |
| smallint promptmode; /* 0: PS1, 1: PS2 */ |
| #endif |
| smallint flag_SIGINT; |
| #if ENABLE_HUSH_LOOPS |
| smallint flag_break_continue; |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| /* 0: outside of a function (or sourced file) |
| * -1: inside of a function, ok to use return builtin |
| * 1: return is invoked, skip all till end of func |
| */ |
| smallint flag_return_in_progress; |
| # define G_flag_return_in_progress (G.flag_return_in_progress) |
| #else |
| # define G_flag_return_in_progress 0 |
| #endif |
| smallint exiting; /* used to prevent EXIT trap recursion */ |
| /* These support $? */ |
| smalluint last_exitcode; |
| smalluint expand_exitcode; |
| smalluint last_bg_pid_exitcode; |
| #if ENABLE_HUSH_SET |
| /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */ |
| smalluint global_args_malloced; |
| # define G_global_args_malloced (G.global_args_malloced) |
| #else |
| # define G_global_args_malloced 0 |
| #endif |
| #if ENABLE_HUSH_BASH_COMPAT |
| int dead_job_exitcode; /* for "wait -n" */ |
| #endif |
| /* how many non-NULL argv's we have. NB: $# + 1 */ |
| int global_argc; |
| char **global_argv; |
| #if !BB_MMU |
| char *argv0_for_re_execing; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| unsigned depth_break_continue; |
| unsigned depth_of_loop; |
| #endif |
| #if ENABLE_HUSH_GETOPTS |
| unsigned getopt_count; |
| #endif |
| const char *ifs; |
| char *ifs_whitespace; /* = G.ifs or malloced */ |
| const char *cwd; |
| struct variable *top_var; |
| char **expanded_assignments; |
| struct variable **shadowed_vars_pp; |
| unsigned var_nest_level; |
| #if ENABLE_HUSH_FUNCTIONS |
| # if ENABLE_HUSH_LOCAL |
| unsigned func_nest_level; /* solely to prevent "local v" in non-functions */ |
| # endif |
| struct function *top_func; |
| #endif |
| /* Signal and trap handling */ |
| #if ENABLE_HUSH_FAST |
| unsigned count_SIGCHLD; |
| unsigned handled_SIGCHLD; |
| smallint we_have_children; |
| #endif |
| #if ENABLE_HUSH_LINENO_VAR |
| unsigned parse_lineno; |
| unsigned execute_lineno; |
| #endif |
| HFILE *HFILE_list; |
| HFILE *HFILE_stdin; |
| /* Which signals have non-DFL handler (even with no traps set)? |
| * Set at the start to: |
| * (SIGQUIT + maybe SPECIAL_INTERACTIVE_SIGS + maybe SPECIAL_JOBSTOP_SIGS) |
| * SPECIAL_INTERACTIVE_SIGS are cleared after fork. |
| * The rest is cleared right before execv syscalls. |
| * Other than these two times, never modified. |
| */ |
| unsigned special_sig_mask; |
| #if ENABLE_HUSH_JOB |
| unsigned fatal_sig_mask; |
| # define G_fatal_sig_mask (G.fatal_sig_mask) |
| #else |
| # define G_fatal_sig_mask 0 |
| #endif |
| #if ENABLE_HUSH_TRAP |
| int pre_trap_exitcode; |
| # if ENABLE_HUSH_FUNCTIONS |
| int return_exitcode; |
| # endif |
| char **traps; /* char *traps[NSIG] */ |
| # define G_traps G.traps |
| #else |
| # define G_traps ((char**)NULL) |
| #endif |
| sigset_t pending_set; |
| #if ENABLE_HUSH_MEMLEAK |
| unsigned long memleak_value; |
| #endif |
| #if ENABLE_HUSH_MODE_X |
| unsigned x_mode_depth; |
| /* "set -x" output should not be redirectable with subsequent 2>FILE. |
| * We dup fd#2 to x_mode_fd when "set -x" is executed, and use it |
| * for all subsequent output. |
| */ |
| int x_mode_fd; |
| o_string x_mode_buf; |
| #endif |
| #if HUSH_DEBUG >= 2 |
| int debug_indent; |
| #endif |
| struct sigaction sa; |
| char optstring_buf[sizeof("eixcs")]; |
| #if BASH_EPOCH_VARS |
| char epoch_buf[sizeof("%llu.nnnnnn") + sizeof(long long)*3]; |
| #endif |
| #if ENABLE_FEATURE_EDITING |
| char user_input_buf[CONFIG_FEATURE_EDITING_MAX_LEN]; |
| #endif |
| }; |
| #define G (*ptr_to_globals) |
| /* Not #defining name to G.name - this quickly gets unwieldy |
| * (too many defines). Also, I actually prefer to see when a variable |
| * is global, thus "G." prefix is a useful hint */ |
| #define INIT_G() do { \ |
| SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| /* memset(&G.sa, 0, sizeof(G.sa)); */ \ |
| sigfillset(&G.sa.sa_mask); \ |
| G.sa.sa_flags = SA_RESTART; \ |
| } while (0) |
| |
| |
| /* Function prototypes for builtins */ |
| static int builtin_cd(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_ECHO |
| static int builtin_echo(char **argv) FAST_FUNC; |
| #endif |
| static int builtin_eval(char **argv) FAST_FUNC; |
| static int builtin_exec(char **argv) FAST_FUNC; |
| static int builtin_exit(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_EXPORT |
| static int builtin_export(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_READONLY |
| static int builtin_readonly(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_JOB |
| static int builtin_fg_bg(char **argv) FAST_FUNC; |
| static int builtin_jobs(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_GETOPTS |
| static int builtin_getopts(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_HELP |
| static int builtin_help(char **argv) FAST_FUNC; |
| #endif |
| #if MAX_HISTORY && ENABLE_FEATURE_EDITING |
| static int builtin_history(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_LOCAL |
| static int builtin_local(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_MEMLEAK |
| static int builtin_memleak(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_PRINTF |
| static int builtin_printf(char **argv) FAST_FUNC; |
| #endif |
| static int builtin_pwd(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_READ |
| static int builtin_read(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_SET |
| static int builtin_set(char **argv) FAST_FUNC; |
| #endif |
| static int builtin_shift(char **argv) FAST_FUNC; |
| static int builtin_source(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_TEST || BASH_TEST2 |
| static int builtin_test(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_TRAP |
| static int builtin_trap(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_TYPE |
| static int builtin_type(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_TIMES |
| static int builtin_times(char **argv) FAST_FUNC; |
| #endif |
| static int builtin_true(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_UMASK |
| static int builtin_umask(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_UNSET |
| static int builtin_unset(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_KILL |
| static int builtin_kill(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_WAIT |
| static int builtin_wait(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| static int builtin_break(char **argv) FAST_FUNC; |
| static int builtin_continue(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| static int builtin_return(char **argv) FAST_FUNC; |
| #endif |
| |
| /* Table of built-in functions. They can be forked or not, depending on |
| * context: within pipes, they fork. As simple commands, they do not. |
| * When used in non-forking context, they can change global variables |
| * in the parent shell process. If forked, of course they cannot. |
| * For example, 'unset foo | whatever' will parse and run, but foo will |
| * still be set at the end. */ |
| struct built_in_command { |
| const char *b_cmd; |
| int (*b_function)(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_HELP |
| const char *b_descr; |
| # define BLTIN(cmd, func, help) { cmd, func, help } |
| #else |
| # define BLTIN(cmd, func, help) { cmd, func } |
| #endif |
| }; |
| |
| static const struct built_in_command bltins1[] ALIGN_PTR = { |
| BLTIN("." , builtin_source , "Run commands in file"), |
| BLTIN(":" , builtin_true , NULL), |
| #if ENABLE_HUSH_JOB |
| BLTIN("bg" , builtin_fg_bg , "Resume job in background"), |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| BLTIN("break" , builtin_break , "Exit loop"), |
| #endif |
| BLTIN("cd" , builtin_cd , "Change directory"), |
| #if ENABLE_HUSH_LOOPS |
| BLTIN("continue" , builtin_continue, "Start new loop iteration"), |
| #endif |
| BLTIN("eval" , builtin_eval , "Construct and run shell command"), |
| BLTIN("exec" , builtin_exec , "Execute command, don't return to shell"), |
| BLTIN("exit" , builtin_exit , NULL), |
| #if ENABLE_HUSH_EXPORT |
| BLTIN("export" , builtin_export , "Set environment variables"), |
| #endif |
| #if ENABLE_HUSH_JOB |
| BLTIN("fg" , builtin_fg_bg , "Bring job to foreground"), |
| #endif |
| #if ENABLE_HUSH_GETOPTS |
| BLTIN("getopts" , builtin_getopts , NULL), |
| #endif |
| #if ENABLE_HUSH_HELP |
| BLTIN("help" , builtin_help , NULL), |
| #endif |
| #if MAX_HISTORY && ENABLE_FEATURE_EDITING |
| BLTIN("history" , builtin_history , "Show history"), |
| #endif |
| #if ENABLE_HUSH_JOB |
| BLTIN("jobs" , builtin_jobs , "List jobs"), |
| #endif |
| #if ENABLE_HUSH_KILL |
| BLTIN("kill" , builtin_kill , "Send signals to processes"), |
| #endif |
| #if ENABLE_HUSH_LOCAL |
| BLTIN("local" , builtin_local , "Set local variables"), |
| #endif |
| #if ENABLE_HUSH_MEMLEAK |
| BLTIN("memleak" , builtin_memleak , NULL), |
| #endif |
| #if ENABLE_HUSH_READ |
| BLTIN("read" , builtin_read , "Input into variable"), |
| #endif |
| #if ENABLE_HUSH_READONLY |
| BLTIN("readonly" , builtin_readonly, "Make variables read-only"), |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| BLTIN("return" , builtin_return , "Return from function"), |
| #endif |
| #if ENABLE_HUSH_SET |
| BLTIN("set" , builtin_set , "Set positional parameters"), |
| #endif |
| BLTIN("shift" , builtin_shift , "Shift positional parameters"), |
| #if BASH_SOURCE |
| BLTIN("source" , builtin_source , NULL), |
| #endif |
| #if ENABLE_HUSH_TIMES |
| BLTIN("times" , builtin_times , NULL), |
| #endif |
| #if ENABLE_HUSH_TRAP |
| BLTIN("trap" , builtin_trap , "Trap signals"), |
| #endif |
| BLTIN("true" , builtin_true , NULL), |
| #if ENABLE_HUSH_TYPE |
| BLTIN("type" , builtin_type , "Show command type"), |
| #endif |
| #if ENABLE_HUSH_ULIMIT |
| BLTIN("ulimit" , shell_builtin_ulimit, "Control resource limits"), |
| #endif |
| #if ENABLE_HUSH_UMASK |
| BLTIN("umask" , builtin_umask , "Set file creation mask"), |
| #endif |
| #if ENABLE_HUSH_UNSET |
| BLTIN("unset" , builtin_unset , "Unset variables"), |
| #endif |
| #if ENABLE_HUSH_WAIT |
| BLTIN("wait" , builtin_wait , "Wait for process to finish"), |
| #endif |
| }; |
| /* These builtins won't be used if we are on NOMMU and need to re-exec |
| * (it's cheaper to run an external program in this case): |
| */ |
| static const struct built_in_command bltins2[] ALIGN_PTR = { |
| #if ENABLE_HUSH_TEST |
| BLTIN("[" , builtin_test , NULL), |
| #endif |
| #if BASH_TEST2 |
| BLTIN("[[" , builtin_test , NULL), |
| #endif |
| #if ENABLE_HUSH_ECHO |
| BLTIN("echo" , builtin_echo , NULL), |
| #endif |
| #if ENABLE_HUSH_PRINTF |
| BLTIN("printf" , builtin_printf , NULL), |
| #endif |
| BLTIN("pwd" , builtin_pwd , NULL), |
| #if ENABLE_HUSH_TEST |
| BLTIN("test" , builtin_test , NULL), |
| #endif |
| }; |
| |
| |
| /* Debug printouts. |
| */ |
| #if HUSH_DEBUG >= 2 |
| /* prevent disasters with G.debug_indent < 0 */ |
| # define indent() fdprintf(2, "%*s", (G.debug_indent * 2) & 0xff, "") |
| # define debug_enter() (G.debug_indent++) |
| # define debug_leave() (G.debug_indent--) |
| #else |
| # define indent() ((void)0) |
| # define debug_enter() ((void)0) |
| # define debug_leave() ((void)0) |
| #endif |
| |
| #ifndef debug_printf |
| # define debug_printf(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_parse |
| # define debug_printf_parse(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_heredoc |
| # define debug_printf_heredoc(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_exec |
| #define debug_printf_exec(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_env |
| # define debug_printf_env(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_jobs |
| # define debug_printf_jobs(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| # define DEBUG_JOBS 1 |
| #else |
| # define DEBUG_JOBS 0 |
| #endif |
| |
| #ifndef debug_printf_expand |
| # define debug_printf_expand(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| # define DEBUG_EXPAND 1 |
| #else |
| # define DEBUG_EXPAND 0 |
| #endif |
| |
| #ifndef debug_printf_varexp |
| # define debug_printf_varexp(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_glob |
| # define debug_printf_glob(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| # define DEBUG_GLOB 1 |
| #else |
| # define DEBUG_GLOB 0 |
| #endif |
| |
| #ifndef debug_printf_redir |
| # define debug_printf_redir(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_list |
| # define debug_printf_list(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_subst |
| # define debug_printf_subst(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_prompt |
| # define debug_printf_prompt(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_clean |
| # define debug_printf_clean(...) (indent(), fdprintf(2, __VA_ARGS__)) |
| # define DEBUG_CLEAN 1 |
| #else |
| # define DEBUG_CLEAN 0 |
| #endif |
| |
| #if DEBUG_EXPAND |
| static void debug_print_strings(const char *prefix, char **vv) |
| { |
| indent(); |
| fdprintf(2, "%s:\n", prefix); |
| while (*vv) |
| fdprintf(2, " '%s'\n", *vv++); |
| } |
| #else |
| # define debug_print_strings(prefix, vv) ((void)0) |
| #endif |
| |
| |
| /* Leak hunting. Use hush_leaktool.sh for post-processing. |
| */ |
| #if LEAK_HUNTING |
| static void *xxmalloc(int lineno, size_t size) |
| { |
| void *ptr = xmalloc((size + 0xff) & ~0xff); |
| fdprintf(2, "line %d: malloc %p\n", lineno, ptr); |
| return ptr; |
| } |
| static void *xxrealloc(int lineno, void *ptr, size_t size) |
| { |
| ptr = xrealloc(ptr, (size + 0xff) & ~0xff); |
| fdprintf(2, "line %d: realloc %p\n", lineno, ptr); |
| return ptr; |
| } |
| static char *xxstrdup(int lineno, const char *str) |
| { |
| char *ptr = xstrdup(str); |
| fdprintf(2, "line %d: strdup %p\n", lineno, ptr); |
| return ptr; |
| } |
| static void xxfree(void *ptr) |
| { |
| fdprintf(2, "free %p\n", ptr); |
| free(ptr); |
| } |
| # define xmalloc(s) xxmalloc(__LINE__, s) |
| # define xrealloc(p, s) xxrealloc(__LINE__, p, s) |
| # define xstrdup(s) xxstrdup(__LINE__, s) |
| # define free(p) xxfree(p) |
| #endif |
| |
| |
| /* Syntax and runtime errors. They always abort scripts. |
| * In interactive use they usually discard unparsed and/or unexecuted commands |
| * and return to the prompt. |
| * HUSH_DEBUG >= 2 prints line number in this file where it was detected. |
| */ |
| #if HUSH_DEBUG < 2 |
| # define msg_and_die_if_script(lineno, ...) msg_and_die_if_script(__VA_ARGS__) |
| # define syntax_error(lineno, msg) syntax_error(msg) |
| # define syntax_error_at(lineno, msg) syntax_error_at(msg) |
| # define syntax_error_unterm_ch(lineno, ch) syntax_error_unterm_ch(ch) |
| # define syntax_error_unterm_str(lineno, s) syntax_error_unterm_str(s) |
| # define syntax_error_unexpected_ch(lineno, ch) syntax_error_unexpected_ch(ch) |
| #endif |
| |
| static void die_if_script(void) |
| { |
| if (!G_interactive_fd) { |
| if (G.last_exitcode) /* sometines it's 2, not 1 (bash compat) */ |
| xfunc_error_retval = G.last_exitcode; |
| xfunc_die(); |
| } |
| } |
| |
| static void msg_and_die_if_script(unsigned lineno, const char *fmt, ...) |
| { |
| va_list p; |
| |
| #if HUSH_DEBUG >= 2 |
| bb_error_msg("hush.c:%u", lineno); |
| #endif |
| va_start(p, fmt); |
| bb_verror_msg(fmt, p, NULL); |
| va_end(p); |
| die_if_script(); |
| } |
| |
| static void syntax_error(unsigned lineno UNUSED_PARAM, const char *msg) |
| { |
| if (msg) |
| bb_error_msg("syntax error: %s", msg); |
| else |
| bb_simple_error_msg("syntax error"); |
| die_if_script(); |
| } |
| |
| static void syntax_error_at(unsigned lineno UNUSED_PARAM, const char *msg) |
| { |
| bb_error_msg("syntax error at '%s'", msg); |
| die_if_script(); |
| } |
| |
| static void syntax_error_unterm_str(unsigned lineno UNUSED_PARAM, const char *s) |
| { |
| bb_error_msg("syntax error: unterminated %s", s); |
| //? source4.tests fails: in bash, echo ${^} in script does not terminate the script |
| // die_if_script(); |
| } |
| |
| static void syntax_error_unterm_ch(unsigned lineno, char ch) |
| { |
| char msg[2] = { ch, '\0' }; |
| syntax_error_unterm_str(lineno, msg); |
| } |
| |
| static void syntax_error_unexpected_ch(unsigned lineno UNUSED_PARAM, int ch) |
| { |
| char msg[2]; |
| msg[0] = ch; |
| msg[1] = '\0'; |
| #if HUSH_DEBUG >= 2 |
| bb_error_msg("hush.c:%u", lineno); |
| #endif |
| bb_error_msg("syntax error: unexpected %s", ch == EOF ? "EOF" : msg); |
| die_if_script(); |
| } |
| |
| #if HUSH_DEBUG < 2 |
| # undef msg_and_die_if_script |
| # undef syntax_error |
| # undef syntax_error_at |
| # undef syntax_error_unterm_ch |
| # undef syntax_error_unterm_str |
| # undef syntax_error_unexpected_ch |
| #else |
| # define msg_and_die_if_script(...) msg_and_die_if_script(__LINE__, __VA_ARGS__) |
| # define syntax_error(msg) syntax_error(__LINE__, msg) |
| # define syntax_error_at(msg) syntax_error_at(__LINE__, msg) |
| # define syntax_error_unterm_ch(ch) syntax_error_unterm_ch(__LINE__, ch) |
| # define syntax_error_unterm_str(s) syntax_error_unterm_str(__LINE__, s) |
| # define syntax_error_unexpected_ch(ch) syntax_error_unexpected_ch(__LINE__, ch) |
| #endif |
| |
| |
| /* Utility functions |
| */ |
| /* Replace each \x with x in place, return ptr past NUL. */ |
| static char *unbackslash(char *src) |
| { |
| char *dst = src = strchrnul(src, '\\'); |
| while (1) { |
| if (*src == '\\') { |
| src++; |
| if (*src != '\0') { |
| /* \x -> x */ |
| *dst++ = *src++; |
| continue; |
| } |
| /* else: "\<nul>". Do not delete this backslash. |
| * Testcase: eval 'echo ok\' |
| */ |
| *dst++ = '\\'; |
| /* fallthrough */ |
| } |
| if ((*dst++ = *src++) == '\0') |
| break; |
| } |
| return dst; |
| } |
| |
| static char **add_strings_to_strings(char **strings, char **add, int need_to_dup) |
| { |
| int i; |
| unsigned count1; |
| unsigned count2; |
| char **v; |
| |
| v = strings; |
| count1 = 0; |
| if (v) { |
| while (*v) { |
| count1++; |
| v++; |
| } |
| } |
| count2 = 0; |
| v = add; |
| while (*v) { |
| count2++; |
| v++; |
| } |
| v = xrealloc(strings, (count1 + count2 + 1) * sizeof(char*)); |
| v[count1 + count2] = NULL; |
| i = count2; |
| while (--i >= 0) |
| v[count1 + i] = (need_to_dup ? xstrdup(add[i]) : add[i]); |
| return v; |
| } |
| #if LEAK_HUNTING |
| static char **xx_add_strings_to_strings(int lineno, char **strings, char **add, int need_to_dup) |
| { |
| char **ptr = add_strings_to_strings(strings, add, need_to_dup); |
| fdprintf(2, "line %d: add_strings_to_strings %p\n", lineno, ptr); |
| return ptr; |
| } |
| #define add_strings_to_strings(strings, add, need_to_dup) \ |
| xx_add_strings_to_strings(__LINE__, strings, add, need_to_dup) |
| #endif |
| |
| /* Note: takes ownership of "add" ptr (it is not strdup'ed) */ |
| static char **add_string_to_strings(char **strings, char *add) |
| { |
| char *v[2]; |
| v[0] = add; |
| v[1] = NULL; |
| return add_strings_to_strings(strings, v, /*dup:*/ 0); |
| } |
| #if LEAK_HUNTING |
| static char **xx_add_string_to_strings(int lineno, char **strings, char *add) |
| { |
| char **ptr = add_string_to_strings(strings, add); |
| fdprintf(2, "line %d: add_string_to_strings %p\n", lineno, ptr); |
| return ptr; |
| } |
| #define add_string_to_strings(strings, add) \ |
| xx_add_string_to_strings(__LINE__, strings, add) |
| #endif |
| |
| static void free_strings(char **strings) |
| { |
| char **v; |
| |
| if (!strings) |
| return; |
| v = strings; |
| while (*v) { |
| free(*v); |
| v++; |
| } |
| free(strings); |
| } |
| |
| static int dup_CLOEXEC(int fd, int avoid_fd) |
| { |
| int newfd; |
| repeat: |
| newfd = fcntl(fd, F_DUPFD_CLOEXEC, avoid_fd + 1); |
| if (newfd >= 0) { |
| if (F_DUPFD_CLOEXEC == F_DUPFD) /* if old libc (w/o F_DUPFD_CLOEXEC) */ |
| fcntl(newfd, F_SETFD, FD_CLOEXEC); |
| } else { /* newfd < 0 */ |
| if (errno == EBUSY) |
| goto repeat; |
| if (errno == EINTR) |
| goto repeat; |
| } |
| return newfd; |
| } |
| |
| static int xdup_CLOEXEC_and_close(int fd, int avoid_fd) |
| { |
| int newfd; |
| repeat: |
| newfd = fcntl(fd, F_DUPFD_CLOEXEC, avoid_fd + 1); |
| if (newfd < 0) { |
| if (errno == EBUSY) |
| goto repeat; |
| if (errno == EINTR) |
| goto repeat; |
| /* fd was not open? */ |
| if (errno == EBADF) |
| return fd; |
| xfunc_die(); |
| } |
| if (F_DUPFD_CLOEXEC == F_DUPFD) /* if old libc (w/o F_DUPFD_CLOEXEC) */ |
| fcntl(newfd, F_SETFD, FD_CLOEXEC); |
| close(fd); |
| return newfd; |
| } |
| |
| |
| /* Manipulating HFILEs */ |
| static HFILE *hfopen(const char *name) |
| { |
| HFILE *fp; |
| int fd; |
| |
| fd = STDIN_FILENO; |
| if (name) { |
| fd = open(name, O_RDONLY | O_CLOEXEC); |
| if (fd < 0) |
| return NULL; |
| if (O_CLOEXEC == 0) /* ancient libc */ |
| close_on_exec_on(fd); |
| } |
| |
| fp = xmalloc(sizeof(*fp)); |
| if (name == NULL) |
| G.HFILE_stdin = fp; |
| fp->fd = fd; |
| fp->cur = fp->end = fp->buf; |
| fp->next_hfile = G.HFILE_list; |
| G.HFILE_list = fp; |
| return fp; |
| } |
| static void hfclose(HFILE *fp) |
| { |
| HFILE **pp = &G.HFILE_list; |
| while (*pp) { |
| HFILE *cur = *pp; |
| if (cur == fp) { |
| *pp = cur->next_hfile; |
| break; |
| } |
| pp = &cur->next_hfile; |
| } |
| if (fp->fd >= 0) |
| close(fp->fd); |
| free(fp); |
| } |
| static int refill_HFILE_and_getc(HFILE *fp) |
| { |
| int n; |
| |
| if (fp->fd < 0) { |
| /* Already saw EOF */ |
| return EOF; |
| } |
| #if ENABLE_HUSH_INTERACTIVE && !ENABLE_FEATURE_EDITING |
| /* If user presses ^C, read() restarts after SIGINT (we use SA_RESTART). |
| * IOW: ^C will not immediately stop line input. |
| * But poll() is different: it does NOT restart after signals. |
| */ |
| if (fp == G.HFILE_stdin) { |
| struct pollfd pfd[1]; |
| pfd[0].fd = fp->fd; |
| pfd[0].events = POLLIN; |
| n = poll(pfd, 1, -1); |
| if (n < 0 |
| /*&& errno == EINTR - assumed true */ |
| && sigismember(&G.pending_set, SIGINT) |
| ) { |
| return '\0'; |
| } |
| } |
| #else |
| /* if FEATURE_EDITING=y, we do not use this routine for interactive input */ |
| #endif |
| /* Try to buffer more input */ |
| n = safe_read(fp->fd, fp->buf, sizeof(fp->buf)); |
| if (n < 0) { |
| bb_simple_perror_msg("read error"); |
| n = 0; |
| } |
| fp->cur = fp->buf; |
| fp->end = fp->buf + n; |
| if (n == 0) { |
| /* EOF/error */ |
| close(fp->fd); |
| fp->fd = -1; |
| return EOF; |
| } |
| return (unsigned char)(*fp->cur++); |
| } |
| /* Inlined for common case of non-empty buffer. |
| */ |
| static ALWAYS_INLINE int hfgetc(HFILE *fp) |
| { |
| if (fp->cur < fp->end) |
| return (unsigned char)(*fp->cur++); |
| /* Buffer empty */ |
| return refill_HFILE_and_getc(fp); |
| } |
| static int move_HFILEs_on_redirect(int fd, int avoid_fd) |
| { |
| HFILE *fl = G.HFILE_list; |
| while (fl) { |
| if (fd == fl->fd) { |
| /* We use it only on script files, they are all CLOEXEC */ |
| fl->fd = xdup_CLOEXEC_and_close(fd, avoid_fd); |
| debug_printf_redir("redirect_fd %d: matches a script fd, moving it to %d\n", fd, fl->fd); |
| return 1; /* "found and moved" */ |
| } |
| fl = fl->next_hfile; |
| } |
| #if ENABLE_HUSH_MODE_X |
| if (G.x_mode_fd > 0 && fd == G.x_mode_fd) { |
| G.x_mode_fd = xdup_CLOEXEC_and_close(fd, avoid_fd); |
| return 1; /* "found and moved" */ |
| } |
| #endif |
| return 0; /* "not in the list" */ |
| } |
| #if ENABLE_FEATURE_SH_STANDALONE && BB_MMU |
| static void close_all_HFILE_list(void) |
| { |
| HFILE *fl = G.HFILE_list; |
| while (fl) { |
| /* hfclose would also free HFILE object. |
| * It is disastrous if we share memory with a vforked parent. |
| * I'm not sure we never come here after vfork. |
| * Therefore just close fd, nothing more. |
| * |
| * ">" instead of ">=": we don't close fd#0, |
| * interactive shell uses hfopen(NULL) as stdin input |
| * which has fl->fd == 0, but fd#0 gets redirected in pipes. |
| * If we'd close it here, then e.g. interactive "set | sort" |
| * with NOFORKed sort, would have sort's input fd closed. |
| */ |
| if (fl->fd > 0) |
| /*hfclose(fl); - unsafe */ |
| close(fl->fd); |
| fl = fl->next_hfile; |
| } |
| } |
| #endif |
| static int fd_in_HFILEs(int fd) |
| { |
| HFILE *fl = G.HFILE_list; |
| while (fl) { |
| if (fl->fd == fd) |
| return 1; |
| fl = fl->next_hfile; |
| } |
| return 0; |
| } |
| |
| |
| /* Helpers for setting new $n and restoring them back |
| */ |
| typedef struct save_arg_t { |
| char *sv_argv0; |
| char **sv_g_argv; |
| int sv_g_argc; |
| IF_HUSH_SET(smallint sv_g_malloced;) |
| } save_arg_t; |
| |
| static void save_and_replace_G_args(save_arg_t *sv, char **argv) |
| { |
| sv->sv_argv0 = argv[0]; |
| sv->sv_g_argv = G.global_argv; |
| sv->sv_g_argc = G.global_argc; |
| IF_HUSH_SET(sv->sv_g_malloced = G.global_args_malloced;) |
| |
| argv[0] = G.global_argv[0]; /* retain $0 */ |
| G.global_argv = argv; |
| IF_HUSH_SET(G.global_args_malloced = 0;) |
| |
| G.global_argc = 1 + string_array_len(argv + 1); |
| } |
| |
| static void restore_G_args(save_arg_t *sv, char **argv) |
| { |
| #if ENABLE_HUSH_SET |
| if (G.global_args_malloced) { |
| /* someone ran "set -- arg1 arg2 ...", undo */ |
| char **pp = G.global_argv; |
| while (*++pp) /* note: does not free $0 */ |
| free(*pp); |
| free(G.global_argv); |
| } |
| #endif |
| argv[0] = sv->sv_argv0; |
| G.global_argv = sv->sv_g_argv; |
| G.global_argc = sv->sv_g_argc; |
| IF_HUSH_SET(G.global_args_malloced = sv->sv_g_malloced;) |
| } |
| |
| |
| /* Basic theory of signal handling in shell |
| * ======================================== |
| * This does not describe what hush does, rather, it is current understanding |
| * what it _should_ do. If it doesn't, it's a bug. |
| * http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap |
| * |
| * Signals are handled only after each pipe ("cmd | cmd | cmd" thing) |
| * is finished or backgrounded. It is the same in interactive and |
| * non-interactive shells, and is the same regardless of whether |
| * a user trap handler is installed or a shell special one is in effect. |
| * ^C or ^Z from keyboard seems to execute "at once" because it usually |
| * backgrounds (i.e. stops) or kills all members of currently running |
| * pipe. |
| * |
| * Wait builtin is interruptible by signals for which user trap is set |
| * or by SIGINT in interactive shell. |
| * |
| * Trap handlers will execute even within trap handlers. (right?) |
| * |
| * User trap handlers are forgotten when subshell ("(cmd)") is entered, |
| * except for handlers set to '' (empty string). |
| * |
| * If job control is off, backgrounded commands ("cmd &") |
| * have SIGINT, SIGQUIT set to SIG_IGN. |
| * |
| * Commands which are run in command substitution ("`cmd`") |
| * have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN. |
| * |
| * Ordinary commands have signals set to SIG_IGN/DFL as inherited |
| * by the shell from its parent. |
| * |
| * Signals which differ from SIG_DFL action |
| * (note: child (i.e., [v]forked) shell is not an interactive shell): |
| * |
| * SIGQUIT: ignore |
| * SIGTERM (interactive): ignore |
| * SIGHUP (interactive): |
| * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit |
| * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore |
| * Note that ^Z is handled not by trapping SIGTSTP, but by seeing |
| * that all pipe members are stopped. Try this in bash: |
| * while :; do :; done - ^Z does not background it |
| * (while :; do :; done) - ^Z backgrounds it |
| * SIGINT (interactive): wait for last pipe, ignore the rest |
| * of the command line, show prompt. NB: ^C does not send SIGINT |
| * to interactive shell while shell is waiting for a pipe, |
| * since shell is bg'ed (is not in foreground process group). |
| * Example 1: this waits 5 sec, but does not execute ls: |
| * "echo $$; sleep 5; ls -l" + "kill -INT <pid>" |
| * Example 2: this does not wait and does not execute ls: |
| * "echo $$; sleep 5 & wait; ls -l" + "kill -INT <pid>" |
| * Example 3: this does not wait 5 sec, but executes ls: |
| * "sleep 5; ls -l" + press ^C |
| * Example 4: this does not wait and does not execute ls: |
| * "sleep 5 & wait; ls -l" + press ^C |
| * |
| * (What happens to signals which are IGN on shell start?) |
| * (What happens with signal mask on shell start?) |
| * |
| * Old implementation |
| * ================== |
| * We use in-kernel pending signal mask to determine which signals were sent. |
| * We block all signals which we don't want to take action immediately, |
| * i.e. we block all signals which need to have special handling as described |
| * above, and all signals which have traps set. |
| * After each pipe execution, we extract any pending signals via sigtimedwait() |
| * and act on them. |
| * |
| * unsigned special_sig_mask: a mask of such "special" signals |
| * sigset_t blocked_set: current blocked signal set |
| * |
| * "trap - SIGxxx": |
| * clear bit in blocked_set unless it is also in special_sig_mask |
| * "trap 'cmd' SIGxxx": |
| * set bit in blocked_set (even if 'cmd' is '') |
| * after [v]fork, if we plan to be a shell: |
| * unblock signals with special interactive handling |
| * (child shell is not interactive), |
| * unset all traps except '' (note: regardless of child shell's type - {}, (), etc) |
| * after [v]fork, if we plan to exec: |
| * POSIX says fork clears pending signal mask in child - no need to clear it. |
| * Restore blocked signal set to one inherited by shell just prior to exec. |
| * |
| * Note: as a result, we do not use signal handlers much. The only uses |
| * are to count SIGCHLDs |
| * and to restore tty pgrp on signal-induced exit. |
| * |
| * Note 2 (compat): |
| * Standard says "When a subshell is entered, traps that are not being ignored |
| * are set to the default actions". bash interprets it so that traps which |
| * are set to '' (ignore) are NOT reset to defaults. We do the same. |
| * |
| * Problem: the above approach makes it unwieldy to catch signals while |
| * we are in read builtin, or while we read commands from stdin: |
| * masked signals are not visible! |
| * |
| * New implementation |
| * ================== |
| * We record each signal we are interested in by installing signal handler |
| * for them - a bit like emulating kernel pending signal mask in userspace. |
| * We are interested in: signals which need to have special handling |
| * as described above, and all signals which have traps set. |
| * Signals are recorded in pending_set. |
| * After each pipe execution, we extract any pending signals |
| * and act on them. |
| * |
| * unsigned special_sig_mask: a mask of shell-special signals. |
| * unsigned fatal_sig_mask: a mask of signals on which we restore tty pgrp. |
| * char *traps[sig] if trap for sig is set (even if it's ''). |
| * sigset_t pending_set: set of sigs we received. |
| * |
| * "trap - SIGxxx": |
| * if sig is in special_sig_mask, set handler back to: |
| * record_pending_signo, or to IGN if it's a tty stop signal |
| * if sig is in fatal_sig_mask, set handler back to sigexit. |
| * else: set handler back to SIG_DFL |
| * "trap 'cmd' SIGxxx": |
| * set handler to record_pending_signo. |
| * "trap '' SIGxxx": |
| * set handler to SIG_IGN. |
| * after [v]fork, if we plan to be a shell: |
| * set signals with special interactive handling to SIG_DFL |
| * (because child shell is not interactive), |
| * unset all traps except '' (note: regardless of child shell's type - {}, (), etc) |
| * after [v]fork, if we plan to exec: |
| * POSIX says fork clears pending signal mask in child - no need to clear it. |
| * |
| * To make wait builtin interruptible, we handle SIGCHLD as special signal, |
| * otherwise (if we leave it SIG_DFL) sigsuspend in wait builtin will not wake up on it. |
| * |
| * Note (compat): |
| * Standard says "When a subshell is entered, traps that are not being ignored |
| * are set to the default actions". bash interprets it so that traps which |
| * are set to '' (ignore) are NOT reset to defaults. We do the same. |
| */ |
| enum { |
| SPECIAL_INTERACTIVE_SIGS = 0 |
| | (1 << SIGTERM) |
| | (1 << SIGINT) |
| | (1 << SIGHUP) |
| , |
| SPECIAL_JOBSTOP_SIGS = 0 |
| #if ENABLE_HUSH_JOB |
| | (1 << SIGTTIN) |
| | (1 << SIGTTOU) |
| | (1 << SIGTSTP) |
| #endif |
| , |
| }; |
| |
| static void record_pending_signo(int sig) |
| { |
| sigaddset(&G.pending_set, sig); |
| #if ENABLE_HUSH_FAST |
| if (sig == SIGCHLD) { |
| G.count_SIGCHLD++; |
| //bb_error_msg("[%d] SIGCHLD_handler: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| } |
| #endif |
| } |
| |
| static sighandler_t install_sighandler(int sig, sighandler_t handler) |
| { |
| struct sigaction old_sa; |
| |
| /* We could use signal() to install handlers... almost: |
| * except that we need to mask ALL signals while handlers run. |
| * I saw signal nesting in strace, race window isn't small. |
| * SA_RESTART is also needed, but in Linux, signal() |
| * sets SA_RESTART too. |
| */ |
| /* memset(&G.sa, 0, sizeof(G.sa)); - already done */ |
| /* sigfillset(&G.sa.sa_mask); - already done */ |
| /* G.sa.sa_flags = SA_RESTART; - already done */ |
| G.sa.sa_handler = handler; |
| sigaction(sig, &G.sa, &old_sa); |
| return old_sa.sa_handler; |
| } |
| |
| static void hush_exit(int exitcode) NORETURN; |
| |
| static void restore_ttypgrp_and__exit(void) NORETURN; |
| static void restore_ttypgrp_and__exit(void) |
| { |
| /* xfunc has failed! die die die */ |
| /* no EXIT traps, this is an escape hatch! */ |
| G.exiting = 1; |
| hush_exit(xfunc_error_retval); |
| } |
| |
| #if ENABLE_HUSH_JOB |
| |
| /* Needed only on some libc: |
| * It was observed that on exit(), fgetc'ed buffered data |
| * gets "unwound" via lseek(fd, -NUM, SEEK_CUR). |
| * With the net effect that even after fork(), not vfork(), |
| * exit() in NOEXECed applet in "sh SCRIPT": |
| * noexec_applet_here |
| * echo END_OF_SCRIPT |
| * lseeks fd in input FILE object from EOF to "e" in "echo END_OF_SCRIPT". |
| * This makes "echo END_OF_SCRIPT" executed twice. |
| * Similar problems can be seen with msg_and_die_if_script() -> xfunc_die() |
| * and in `cmd` handling. |
| * If set as die_func(), this makes xfunc_die() exit via _exit(), not exit(): |
| */ |
| static void fflush_and__exit(void) NORETURN; |
| static void fflush_and__exit(void) |
| { |
| fflush_all(); |
| _exit(xfunc_error_retval); |
| } |
| |
| /* After [v]fork, in child: do not restore tty pgrp on xfunc death */ |
| # define disable_restore_tty_pgrp_on_exit() (die_func = fflush_and__exit) |
| /* After [v]fork, in parent: restore tty pgrp on xfunc death */ |
| # define enable_restore_tty_pgrp_on_exit() (die_func = restore_ttypgrp_and__exit) |
| |
| /* Restores tty foreground process group, and exits. |
| * May be called as signal handler for fatal signal |
| * (will resend signal to itself, producing correct exit state) |
| * or called directly with -EXITCODE. |
| * We also call it if xfunc is exiting. |
| */ |
| static void sigexit(int sig) NORETURN; |
| static void sigexit(int sig) |
| { |
| /* Careful: we can end up here after [v]fork. Do not restore |
| * tty pgrp then, only top-level shell process does that */ |
| if (G_saved_tty_pgrp && getpid() == G.root_pid) { |
| /* Disable all signals: job control, SIGPIPE, etc. |
| * Mostly paranoid measure, to prevent infinite SIGTTOU. |
| */ |
| sigprocmask_allsigs(SIG_BLOCK); |
| tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp); |
| } |
| |
| /* Not a signal, just exit */ |
| if (sig <= 0) |
| _exit(- sig); |
| |
| kill_myself_with_sig(sig); /* does not return */ |
| } |
| #else |
| |
| # define disable_restore_tty_pgrp_on_exit() ((void)0) |
| # define enable_restore_tty_pgrp_on_exit() ((void)0) |
| |
| #endif |
| |
| static sighandler_t pick_sighandler(unsigned sig) |
| { |
| sighandler_t handler = SIG_DFL; |
| if (sig < sizeof(unsigned)*8) { |
| unsigned sigmask = (1 << sig); |
| |
| #if ENABLE_HUSH_JOB |
| /* is sig fatal? */ |
| if (G_fatal_sig_mask & sigmask) |
| handler = sigexit; |
| else |
| #endif |
| /* sig has special handling? */ |
| if (G.special_sig_mask & sigmask) { |
| handler = record_pending_signo; |
| /* TTIN/TTOU/TSTP can't be set to record_pending_signo |
| * in order to ignore them: they will be raised |
| * in an endless loop when we try to do some |
| * terminal ioctls! We do have to _ignore_ these. |
| */ |
| if (SPECIAL_JOBSTOP_SIGS & sigmask) |
| handler = SIG_IGN; |
| } |
| } |
| return handler; |
| } |
| |
| /* Restores tty foreground process group, and exits. */ |
| static void hush_exit(int exitcode) |
| { |
| #if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT |
| save_history(G.line_input_state); /* may be NULL */ |
| #endif |
| |
| fflush_all(); |
| if (G.exiting <= 0 && G_traps && G_traps[0] && G_traps[0][0]) { |
| char *argv[3]; |
| /* argv[0] is unused */ |
| argv[1] = xstrdup(G_traps[0]); /* copy, since EXIT trap handler may modify G_traps[0] */ |
| argv[2] = NULL; |
| G.exiting = 1; /* prevent EXIT trap recursion */ |
| /* Note: G_traps[0] is not cleared! |
| * "trap" will still show it, if executed |
| * in the handler */ |
| builtin_eval(argv); |
| } |
| |
| #if ENABLE_FEATURE_CLEAN_UP |
| { |
| struct variable *cur_var; |
| if (G.cwd != bb_msg_unknown) |
| free((char*)G.cwd); |
| cur_var = G.top_var; |
| while (cur_var) { |
| struct variable *tmp = cur_var; |
| if (!cur_var->max_len) |
| free(cur_var->varstr); |
| cur_var = cur_var->next; |
| free(tmp); |
| } |
| } |
| #endif |
| |
| fflush_all(); |
| #if ENABLE_HUSH_JOB |
| sigexit(- (exitcode & 0xff)); |
| #else |
| _exit(exitcode); |
| #endif |
| } |
| |
| //TODO: return a mask of ALL handled sigs? |
| static int check_and_run_traps(void) |
| { |
| int last_sig = 0; |
| |
| while (1) { |
| int sig; |
| |
| if (sigisemptyset(&G.pending_set)) |
| break; |
| sig = 0; |
| do { |
| sig++; |
| if (sigismember(&G.pending_set, sig)) { |
| sigdelset(&G.pending_set, sig); |
| goto got_sig; |
| } |
| } while (sig < NSIG); |
| break; |
| got_sig: |
| #if ENABLE_HUSH_TRAP |
| if (G_traps && G_traps[sig]) { |
| debug_printf_exec("%s: sig:%d handler:'%s'\n", __func__, sig, G.traps[sig]); |
| if (G_traps[sig][0]) { |
| /* We have user-defined handler */ |
| smalluint save_rcode; |
| int save_pre; |
| char *argv[3]; |
| /* argv[0] is unused */ |
| argv[1] = xstrdup(G_traps[sig]); |
| /* why strdup? trap can modify itself: trap 'trap "echo oops" INT' INT */ |
| argv[2] = NULL; |
| save_pre = G.pre_trap_exitcode; |
| G.pre_trap_exitcode = save_rcode = G.last_exitcode; |
| builtin_eval(argv); |
| free(argv[1]); |
| G.pre_trap_exitcode = save_pre; |
| G.last_exitcode = save_rcode; |
| # if ENABLE_HUSH_FUNCTIONS |
| if (G.return_exitcode >= 0) { |
| debug_printf_exec("trap exitcode:%d\n", G.return_exitcode); |
| G.last_exitcode = G.return_exitcode; |
| } |
| # endif |
| last_sig = sig; |
| } /* else: "" trap, ignoring signal */ |
| continue; |
| } |
| #endif |
| /* not a trap: special action */ |
| switch (sig) { |
| case SIGINT: |
| debug_printf_exec("%s: sig:%d default SIGINT handler\n", __func__, sig); |
| G.flag_SIGINT = 1; |
| last_sig = sig; |
| break; |
| #if ENABLE_HUSH_JOB |
| case SIGHUP: { |
| //TODO: why are we doing this? ash and dash don't do this, |
| //they have no handler for SIGHUP at all, |
| //they rely on kernel to send SIGHUP+SIGCONT to orphaned process groups |
| struct pipe *job; |
| debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig); |
| /* bash is observed to signal whole process groups, |
| * not individual processes */ |
| for (job = G.job_list; job; job = job->next) { |
| if (job->pgrp <= 0) |
| continue; |
| debug_printf_exec("HUPing pgrp %d\n", job->pgrp); |
| if (kill(- job->pgrp, SIGHUP) == 0) |
| kill(- job->pgrp, SIGCONT); |
| } |
| sigexit(SIGHUP); |
| } |
| #endif |
| #if ENABLE_HUSH_FAST |
| case SIGCHLD: |
| debug_printf_exec("%s: sig:%d default SIGCHLD handler\n", __func__, sig); |
| G.count_SIGCHLD++; |
| //bb_error_msg("[%d] check_and_run_traps: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| /* Note: |
| * We don't do 'last_sig = sig' here -> NOT returning this sig. |
| * This simplifies wait builtin a bit. |
| */ |
| break; |
| #endif |
| default: /* ignored: */ |
| debug_printf_exec("%s: sig:%d default handling is to ignore\n", __func__, sig); |
| /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */ |
| /* Note: |
| * We don't do 'last_sig = sig' here -> NOT returning this sig. |
| * Example: wait is not interrupted by TERM |
| * in interactive shell, because TERM is ignored. |
| */ |
| break; |
| } |
| } |
| return last_sig; |
| } |
| |
| |
| static const char *get_cwd(int force) |
| { |
| if (force || G.cwd == NULL) { |
| /* xrealloc_getcwd_or_warn(arg) calls free(arg), |
| * we must not try to free(bb_msg_unknown) */ |
| if (G.cwd == bb_msg_unknown) |
| G.cwd = NULL; |
| G.cwd = xrealloc_getcwd_or_warn((char *)G.cwd); |
| if (!G.cwd) |
| G.cwd = bb_msg_unknown; |
| } |
| return G.cwd; |
| } |
| |
| |
| /* |
| * Shell and environment variable support |
| */ |
| static struct variable **get_ptr_to_local_var(const char *name, unsigned len) |
| { |
| struct variable **pp; |
| struct variable *cur; |
| |
| pp = &G.top_var; |
| while ((cur = *pp) != NULL) { |
| if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=') |
| return pp; |
| pp = &cur->next; |
| } |
| return NULL; |
| } |
| |
| static const char* FAST_FUNC get_local_var_value(const char *name) |
| { |
| struct variable **vpp; |
| unsigned len = strlen(name); |
| |
| if (G.expanded_assignments) { |
| char **cpp = G.expanded_assignments; |
| while (*cpp) { |
| char *cp = *cpp; |
| if (strncmp(cp, name, len) == 0 && cp[len] == '=') |
| return cp + len + 1; |
| cpp++; |
| } |
| } |
| |
| vpp = get_ptr_to_local_var(name, len); |
| if (vpp) |
| return (*vpp)->varstr + len + 1; |
| |
| if (strcmp(name, "PPID") == 0) |
| return utoa(G.root_ppid); |
| // bash compat: UID? EUID? |
| #if ENABLE_HUSH_RANDOM_SUPPORT |
| if (strcmp(name, "RANDOM") == 0) |
| return utoa(next_random(&G.random_gen)); |
| #endif |
| #if ENABLE_HUSH_LINENO_VAR |
| if (strcmp(name, "LINENO") == 0) |
| return utoa(G.execute_lineno); |
| #endif |
| #if BASH_EPOCH_VARS |
| { |
| const char *fmt = NULL; |
| if (strcmp(name, "EPOCHSECONDS") == 0) |
| fmt = "%llu"; |
| else if (strcmp(name, "EPOCHREALTIME") == 0) |
| fmt = "%llu.%06u"; |
| if (fmt) { |
| struct timeval tv; |
| xgettimeofday(&tv); |
| sprintf(G.epoch_buf, fmt, (unsigned long long)tv.tv_sec, |
| (unsigned)tv.tv_usec); |
| return G.epoch_buf; |
| } |
| } |
| #endif |
| return NULL; |
| } |
| |
| #if ENABLE_HUSH_GETOPTS |
| static void handle_changed_special_names(const char *name, unsigned name_len) |
| { |
| if (name_len == 6) { |
| if (strncmp(name, "OPTIND", 6) == 0) { |
| G.getopt_count = 0; |
| return; |
| } |
| } |
| } |
| #else |
| /* Do not even bother evaluating arguments */ |
| # define handle_changed_special_names(...) ((void)0) |
| #endif |
| |
| /* str holds "NAME=VAL" and is expected to be malloced. |
| * We take ownership of it. |
| */ |
| #define SETFLAG_EXPORT (1 << 0) |
| #define SETFLAG_UNEXPORT (1 << 1) |
| #define SETFLAG_MAKE_RO (1 << 2) |
| #define SETFLAG_VARLVL_SHIFT 3 |
| static int set_local_var(char *str, unsigned flags) |
| { |
| struct variable **cur_pp; |
| struct variable *cur; |
| char *free_me = NULL; |
| char *eq_sign; |
| int name_len; |
| int retval; |
| unsigned local_lvl = (flags >> SETFLAG_VARLVL_SHIFT); |
| |
| eq_sign = strchr(str, '='); |
| if (HUSH_DEBUG && !eq_sign) |
| bb_simple_error_msg_and_die("BUG in setvar"); |
| |
| name_len = eq_sign - str + 1; /* including '=' */ |
| cur_pp = &G.top_var; |
| while ((cur = *cur_pp) != NULL) { |
| if (strncmp(cur->varstr, str, name_len) != 0) { |
| cur_pp = &cur->next; |
| continue; |
| } |
| |
| /* We found an existing var with this name */ |
| if (cur->flg_read_only) { |
| bb_error_msg("%s: readonly variable", str); |
| free(str); |
| //NOTE: in bash, assignment in "export READONLY_VAR=Z" fails, and sets $?=1, |
| //but export per se succeeds (does put the var in env). We don't mimic that. |
| return -1; |
| } |
| if (flags & SETFLAG_UNEXPORT) { // && cur->flg_export ? |
| debug_printf_env("%s: unsetenv '%s'\n", __func__, str); |
| *eq_sign = '\0'; |
| unsetenv(str); |
| *eq_sign = '='; |
| } |
| if (cur->var_nest_level < local_lvl) { |
| /* bash 3.2.33(1) and exported vars: |
| * # export z=z |
| * # f() { local z=a; env | grep ^z; } |
| * # f |
| * z=a |
| * # env | grep ^z |
| * z=z |
| */ |
| if (cur->flg_export) |
| flags |= SETFLAG_EXPORT; |
| /* New variable is local ("local VAR=VAL" or |
| * "VAR=VAL cmd") |
| * and existing one is global, or local |
| * on a lower level that new one. |
| * Remove it from global variable list: |
| */ |
| *cur_pp = cur->next; |
| if (G.shadowed_vars_pp) { |
| /* Save in "shadowed" list */ |
| debug_printf_env("shadowing %s'%s'/%u by '%s'/%u\n", |
| cur->flg_export ? "exported " : "", |
| cur->varstr, cur->var_nest_level, str, local_lvl |
| ); |
| cur->next = *G.shadowed_vars_pp; |
| *G.shadowed_vars_pp = cur; |
| } else { |
| /* Came from pseudo_exec_argv(), no need to save: delete it */ |
| debug_printf_env("shadow-deleting %s'%s'/%u by '%s'/%u\n", |
| cur->flg_export ? "exported " : "", |
| cur->varstr, cur->var_nest_level, str, local_lvl |
| ); |
| if (cur->max_len == 0) /* allocated "VAR=VAL"? */ |
| free_me = cur->varstr; /* then free it later */ |
| free(cur); |
| } |
| break; |
| } |
| |
| if (strcmp(cur->varstr + name_len, eq_sign + 1) == 0) { |
| debug_printf_env("assignement '%s' does not change anything\n", str); |
| free_and_exp: |
| free(str); |
| goto exp; |
| } |
| |
| /* Replace the value in the found "struct variable" */ |
| if (cur->max_len != 0) { |
| if (cur->max_len >= strnlen(str, cur->max_len + 1)) { |
| /* This one is from startup env, reuse space */ |
| debug_printf_env("reusing startup env for '%s'\n", str); |
| strcpy(cur->varstr, str); |
| goto free_and_exp; |
| } |
| /* Can't reuse */ |
| cur->max_len = 0; |
| goto set_str_and_exp; |
| } |
| /* max_len == 0 signifies "malloced" var, which we can |
| * (and have to) free. But we can't free(cur->varstr) here: |
| * if cur->flg_export is 1, it is in the environment. |
| * We should either unsetenv+free, or wait until putenv, |
| * then putenv(new)+free(old). |
| */ |
| free_me = cur->varstr; |
| goto set_str_and_exp; |
| } |
| |
| /* Not found or shadowed - create new variable struct */ |
| debug_printf_env("%s: alloc new var '%s'/%u\n", __func__, str, local_lvl); |
| cur = xzalloc(sizeof(*cur)); |
| cur->var_nest_level = local_lvl; |
| cur->next = *cur_pp; |
| *cur_pp = cur; |
| |
| set_str_and_exp: |
| cur->varstr = str; |
| exp: |
| #if !BB_MMU || ENABLE_HUSH_READONLY |
| if (flags & SETFLAG_MAKE_RO) { |
| cur->flg_read_only = 1; |
| } |
| #endif |
| if (flags & SETFLAG_EXPORT) |
| cur->flg_export = 1; |
| retval = 0; |
| if (cur->flg_export) { |
| if (flags & SETFLAG_UNEXPORT) { |
| cur->flg_export = 0; |
| /* unsetenv was already done */ |
| } else { |
| debug_printf_env("%s: putenv '%s'/%u\n", __func__, cur->varstr, cur->var_nest_level); |
| retval = putenv(cur->varstr); |
| /* fall through to "free(free_me)" - |
| * only now we can free old exported malloced string |
| */ |
| } |
| } |
| free(free_me); |
| |
| handle_changed_special_names(cur->varstr, name_len - 1); |
| |
| return retval; |
| } |
| |
| static void FAST_FUNC set_local_var_from_halves(const char *name, const char *val) |
| { |
| char *var = xasprintf("%s=%s", name, val); |
| set_local_var(var, /*flag:*/ 0); |
| } |
| |
| /* Used at startup and after each cd */ |
| static void set_pwd_var(unsigned flag) |
| { |
| set_local_var(xasprintf("PWD=%s", get_cwd(/*force:*/ 1)), flag); |
| } |
| |
| #if ENABLE_HUSH_UNSET || ENABLE_HUSH_GETOPTS |
| static int unset_local_var_len(const char *name, int name_len) |
| { |
| struct variable *cur; |
| struct variable **cur_pp; |
| |
| cur_pp = &G.top_var; |
| while ((cur = *cur_pp) != NULL) { |
| if (strncmp(cur->varstr, name, name_len) == 0 |
| && cur->varstr[name_len] == '=' |
| ) { |
| if (cur->flg_read_only) { |
| bb_error_msg("%s: readonly variable", name); |
| return EXIT_FAILURE; |
| } |
| |
| *cur_pp = cur->next; |
| debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr); |
| bb_unsetenv(cur->varstr); |
| if (!cur->max_len) |
| free(cur->varstr); |
| free(cur); |
| |
| break; |
| } |
| cur_pp = &cur->next; |
| } |
| |
| /* Handle "unset LINENO" et al even if did not find the variable to unset */ |
| handle_changed_special_names(name, name_len); |
| |
| return EXIT_SUCCESS; |
| } |
| |
| static int unset_local_var(const char *name) |
| { |
| return unset_local_var_len(name, strlen(name)); |
| } |
| #endif |
| |
| |
| /* |
| * Helpers for "var1=val1 var2=val2 cmd" feature |
| */ |
| static void add_vars(struct variable *var) |
| { |
| struct variable *next; |
| |
| while (var) { |
| next = var->next; |
| var->next = G.top_var; |
| G.top_var = var; |
| if (var->flg_export) { |
| debug_printf_env("%s: restoring exported '%s'/%u\n", __func__, var->varstr, var->var_nest_level); |
| putenv(var->varstr); |
| } else { |
| debug_printf_env("%s: restoring variable '%s'/%u\n", __func__, var->varstr, var->var_nest_level); |
| } |
| var = next; |
| } |
| } |
| |
| /* We put strings[i] into variable table and possibly putenv them. |
| * If variable is read only, we can free the strings[i] |
| * which attempts to overwrite it. |
| * The strings[] vector itself is freed. |
| */ |
| static void set_vars_and_save_old(char **strings) |
| { |
| char **s; |
| |
| if (!strings) |
| return; |
| |
| s = strings; |
| while (*s) { |
| struct variable *var_p; |
| struct variable **var_pp; |
| char *eq; |
| |
| eq = strchr(*s, '='); |
| if (HUSH_DEBUG && !eq) |
| bb_simple_error_msg_and_die("BUG in varexp4"); |
| var_pp = get_ptr_to_local_var(*s, eq - *s); |
| if (var_pp) { |
| var_p = *var_pp; |
| if (var_p->flg_read_only) { |
| char **p; |
| bb_error_msg("%s: readonly variable", *s); |
| /* |
| * "VAR=V BLTIN" unsets VARs after BLTIN completes. |
| * If VAR is readonly, leaving it in the list |
| * after asssignment error (msg above) |
| * causes doubled error message later, on unset. |
| */ |
| debug_printf_env("removing/freeing '%s' element\n", *s); |
| free(*s); |
| p = s; |
| do { *p = p[1]; p++; } while (*p); |
| goto next; |
| } |
| /* below, set_local_var() with nest level will |
| * "shadow" (remove) this variable from |
| * global linked list. |
| */ |
| } |
| debug_printf_env("%s: env override '%s'/%u\n", __func__, *s, G.var_nest_level); |
| set_local_var(*s, (G.var_nest_level << SETFLAG_VARLVL_SHIFT) | SETFLAG_EXPORT); |
| s++; |
| next: ; |
| } |
| free(strings); |
| } |
| |
| |
| /* |
| * Unicode helper |
| */ |
| static void reinit_unicode_for_hush(void) |
| { |
| /* Unicode support should be activated even if LANG is set |
| * _during_ shell execution, not only if it was set when |
| * shell was started. Therefore, re-check LANG every time: |
| */ |
| if (ENABLE_FEATURE_CHECK_UNICODE_IN_ENV |
| || ENABLE_UNICODE_USING_LOCALE |
| ) { |
| const char *s = get_local_var_value("LC_ALL"); |
| if (!s) s = get_local_var_value("LC_CTYPE"); |
| if (!s) s = get_local_var_value("LANG"); |
| reinit_unicode(s); |
| } |
| } |
| |
| /* |
| * in_str support (strings, and "strings" read from files). |
| */ |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| /* To test correct lineedit/interactive behavior, type from command line: |
| * echo $P\ |
| * \ |
| * AT\ |
| * H\ |
| * \ |
| * It exercises a lot of corner cases. |
| */ |
| static const char *setup_prompt_string(void) |
| { |
| const char *prompt_str; |
| |
| debug_printf_prompt("%s promptmode:%d\n", __func__, G.promptmode); |
| |
| # if ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| prompt_str = get_local_var_value(G.promptmode == 0 ? "PS1" : "PS2"); |
| if (!prompt_str) |
| prompt_str = ""; |
| # else |
| prompt_str = "> "; /* if PS2, else... */ |
| if (G.promptmode == 0) { /* PS1 */ |
| /* No fancy prompts supported, (re)generate "CURDIR $ " by hand */ |
| free(G.PS1); |
| /* bash uses $PWD value, even if it is set by user. |
| * It uses current dir only if PWD is unset. |
| * We always use current dir. */ |
| prompt_str = G.PS1 = xasprintf("%s %c ", get_cwd(0), (geteuid() != 0) ? '$' : '#'); |
| } |
| # endif |
| debug_printf("prompt_str '%s'\n", prompt_str); |
| return prompt_str; |
| } |
| static int get_user_input(struct in_str *i) |
| { |
| # if ENABLE_FEATURE_EDITING |
| /* In EDITING case, this function reads next input line, |
| * saves it in i->p, then returns 1st char of it. |
| */ |
| int r; |
| const char *prompt_str; |
| |
| prompt_str = setup_prompt_string(); |
| for (;;) { |
| reinit_unicode_for_hush(); |
| G.flag_SIGINT = 0; |
| /* buglet: SIGINT will not make new prompt to appear _at once_, |
| * only after <Enter>. (^C works immediately) */ |
| r = read_line_input(G.line_input_state, prompt_str, |
| G.user_input_buf, CONFIG_FEATURE_EDITING_MAX_LEN-1 |
| ); |
| /* read_line_input intercepts ^C, "convert" it to SIGINT */ |
| if (r == 0) { |
| raise(SIGINT); |
| } |
| check_and_run_traps(); |
| if (r != 0 && !G.flag_SIGINT) |
| break; |
| /* ^C or SIGINT: repeat */ |
| /* bash prints ^C even on real SIGINT (non-kbd generated) */ |
| write(STDOUT_FILENO, "^C\n", 3); |
| G.last_exitcode = 128 | SIGINT; |
| } |
| if (r < 0) { |
| /* EOF/error detected */ |
| /* ^D on interactive input goes to next line before exiting: */ |
| write(STDOUT_FILENO, "\n", 1); |
| i->p = NULL; |
| i->peek_buf[0] = r = EOF; |
| return r; |
| } |
| i->p = G.user_input_buf; |
| return (unsigned char)*i->p++; |
| # else |
| /* In !EDITING case, this function gets called for every char. |
| * Buffering happens deeper in the call chain, in hfgetc(i->file). |
| */ |
| int r; |
| |
| for (;;) { |
| G.flag_SIGINT = 0; |
| if (i->last_char == '\0' || i->last_char == '\n') { |
| const char *prompt_str = setup_prompt_string(); |
| /* Why check_and_run_traps here? Try this interactively: |
| * $ trap 'echo INT' INT; (sleep 2; kill -INT $$) & |
| * $ <[enter], repeatedly...> |
| * Without check_and_run_traps, handler never runs. |
| */ |
| check_and_run_traps(); |
| fputs_stdout(prompt_str); |
| fflush_all(); |
| } |
| r = hfgetc(i->file); |
| /* In !ENABLE_FEATURE_EDITING we don't use read_line_input, |
| * no ^C masking happens during fgetc, no special code for ^C: |
| * it generates SIGINT as usual. |
| */ |
| check_and_run_traps(); |
| if (r != '\0' && !G.flag_SIGINT) |
| break; |
| if (G.flag_SIGINT) { |
| /* ^C or SIGINT: repeat */ |
| /* bash prints ^C even on real SIGINT (non-kbd generated) */ |
| /* kernel prints "^C" itself, just print newline: */ |
| write(STDOUT_FILENO, "\n", 1); |
| G.last_exitcode = 128 | SIGINT; |
| } |
| } |
| return r; |
| # endif |
| } |
| /* This is the magic location that prints prompts |
| * and gets data back from the user */ |
| static int fgetc_interactive(struct in_str *i) |
| { |
| int ch; |
| /* If it's interactive stdin, get new line. */ |
| if (G_interactive_fd && i->file == G.HFILE_stdin) { |
| /* Returns first char (or EOF), the rest is in i->p[] */ |
| ch = get_user_input(i); |
| G.promptmode = 1; /* PS2 */ |
| debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode); |
| } else { |
| /* Not stdin: script file, sourced file, etc */ |
| do ch = hfgetc(i->file); while (ch == '\0'); |
| } |
| return ch; |
| } |
| #else /* !INTERACTIVE */ |
| static ALWAYS_INLINE int fgetc_interactive(struct in_str *i) |
| { |
| int ch; |
| do ch = hfgetc(i->file); while (ch == '\0'); |
| return ch; |
| } |
| #endif /* !INTERACTIVE */ |
| |
| static int i_getch(struct in_str *i) |
| { |
| int ch; |
| |
| if (!i->file) { |
| /* string-based in_str */ |
| ch = (unsigned char)*i->p; |
| if (ch != '\0') { |
| i->p++; |
| i->last_char = ch; |
| #if ENABLE_HUSH_LINENO_VAR |
| if (ch == '\n') { |
| G.parse_lineno++; |
| debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno); |
| } |
| #endif |
| return ch; |
| } |
| return EOF; |
| } |
| |
| /* FILE-based in_str */ |
| |
| #if ENABLE_FEATURE_EDITING |
| /* This can be stdin, check line editing char[] buffer */ |
| if (i->p && *i->p != '\0') { |
| ch = (unsigned char)*i->p++; |
| goto out; |
| } |
| #endif |
| /* peek_buf[] is an int array, not char. Can contain EOF. */ |
| ch = i->peek_buf[0]; |
| if (ch != 0) { |
| int ch2 = i->peek_buf[1]; |
| i->peek_buf[0] = ch2; |
| if (ch2 == 0) /* very likely, avoid redundant write */ |
| goto out; |
| i->peek_buf[1] = 0; |
| goto out; |
| } |
| |
| ch = fgetc_interactive(i); |
| out: |
| debug_printf("file_get: got '%c' %d\n", ch, ch); |
| i->last_char = ch; |
| #if ENABLE_HUSH_LINENO_VAR |
| if (ch == '\n') { |
| G.parse_lineno++; |
| debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno); |
| } |
| #endif |
| return ch; |
| } |
| |
| static int i_peek(struct in_str *i) |
| { |
| int ch; |
| |
| if (!i->file) { |
| /* string-based in_str */ |
| /* Doesn't report EOF on NUL. None of the callers care. */ |
| return (unsigned char)*i->p; |
| } |
| |
| /* FILE-based in_str */ |
| |
| #if ENABLE_FEATURE_EDITING && ENABLE_HUSH_INTERACTIVE |
| /* This can be stdin, check line editing char[] buffer */ |
| if (i->p && *i->p != '\0') |
| return (unsigned char)*i->p; |
| #endif |
| /* peek_buf[] is an int array, not char. Can contain EOF. */ |
| ch = i->peek_buf[0]; |
| if (ch != 0) |
| return ch; |
| |
| /* Need to get a new char */ |
| ch = fgetc_interactive(i); |
| debug_printf("file_peek: got '%c' %d\n", ch, ch); |
| |
| /* Save it by either rolling back line editing buffer, or in i->peek_buf[0] */ |
| #if ENABLE_FEATURE_EDITING && ENABLE_HUSH_INTERACTIVE |
| if (i->p) { |
| i->p -= 1; |
| return ch; |
| } |
| #endif |
| i->peek_buf[0] = ch; |
| /*i->peek_buf[1] = 0; - already is */ |
| return ch; |
| } |
| |
| /* Only ever called if i_peek() was called, and did not return EOF. |
| * IOW: we know the previous peek saw an ordinary char, not EOF, not NUL, |
| * not end-of-line. Therefore we never need to read a new editing line here. |
| */ |
| static int i_peek2(struct in_str *i) |
| { |
| int ch; |
| |
| /* There are two cases when i->p[] buffer exists. |
| * (1) it's a string in_str. |
| * (2) It's a file, and we have a saved line editing buffer. |
| * In both cases, we know that i->p[0] exists and not NUL, and |
| * the peek2 result is in i->p[1]. |
| */ |
| if (i->p) |
| return (unsigned char)i->p[1]; |
| |
| /* Now we know it is a file-based in_str. */ |
| |
| /* peek_buf[] is an int array, not char. Can contain EOF. */ |
| /* Is there 2nd char? */ |
| ch = i->peek_buf[1]; |
| if (ch == 0) { |
| /* We did not read it yet, get it now */ |
| do ch = hfgetc(i->file); while (ch == '\0'); |
| i->peek_buf[1] = ch; |
| } |
| |
| debug_printf("file_peek2: got '%c' %d\n", ch, ch); |
| return ch; |
| } |
| |
| static int i_getch_and_eat_bkslash_nl(struct in_str *input) |
| { |
| for (;;) { |
| int ch, ch2; |
| |
| ch = i_getch(input); |
| if (ch != '\\') |
| return ch; |
| ch2 = i_peek(input); |
| if (ch2 != '\n') |
| return ch; |
| /* backslash+newline, skip it */ |
| i_getch(input); |
| } |
| } |
| |
| /* Note: this function _eats_ \<newline> pairs, safe to use plain |
| * i_getch() after it instead of i_getch_and_eat_bkslash_nl(). |
| */ |
| static int i_peek_and_eat_bkslash_nl(struct in_str *input) |
| { |
| for (;;) { |
| int ch, ch2; |
| |
| ch = i_peek(input); |
| if (ch != '\\') |
| return ch; |
| ch2 = i_peek2(input); |
| if (ch2 != '\n') |
| return ch; |
| /* backslash+newline, skip it */ |
| i_getch(input); |
| i_getch(input); |
| } |
| } |
| |
| static void setup_file_in_str(struct in_str *i, HFILE *fp) |
| { |
| memset(i, 0, sizeof(*i)); |
| i->file = fp; |
| /* i->p = NULL; */ |
| } |
| |
| static void setup_string_in_str(struct in_str *i, const char *s) |
| { |
| memset(i, 0, sizeof(*i)); |
| /*i->file = NULL */; |
| i->p = s; |
| } |
| |
| |
| /* |
| * o_string support |
| */ |
| #define B_CHUNK (32 * sizeof(char*)) |
| |
| static void o_reset_to_empty_unquoted(o_string *o) |
| { |
| o->length = 0; |
| o->has_quoted_part = 0; |
| if (o->data) |
| o->data[0] = '\0'; |
| } |
| |
| static void o_free_and_set_NULL(o_string *o) |
| { |
| free(o->data); |
| memset(o, 0, sizeof(*o)); |
| } |
| |
| static ALWAYS_INLINE void o_free(o_string *o) |
| { |
| free(o->data); |
| } |
| |
| static void o_grow_by(o_string *o, int len) |
| { |
| if (o->length + len > o->maxlen) { |
| o->maxlen += (2 * len) | (B_CHUNK-1); |
| o->data = xrealloc(o->data, 1 + o->maxlen); |
| } |
| } |
| |
| static void o_addchr(o_string *o, int ch) |
| { |
| debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o); |
| if (o->length < o->maxlen) { |
| /* likely. avoid o_grow_by() call */ |
| add: |
| o->data[o->length] = ch; |
| o->length++; |
| o->data[o->length] = '\0'; |
| return; |
| } |
| o_grow_by(o, 1); |
| goto add; |
| } |
| |
| #if 0 |
| /* Valid only if we know o_string is not empty */ |
| static void o_delchr(o_string *o) |
| { |
| o->length--; |
| o->data[o->length] = '\0'; |
| } |
| #endif |
| |
| static void o_addblock(o_string *o, const char *str, int len) |
| { |
| o_grow_by(o, len); |
| ((char*)mempcpy(&o->data[o->length], str, len))[0] = '\0'; |
| o->length += len; |
| } |
| |
| static void o_addstr(o_string *o, const char *str) |
| { |
| o_addblock(o, str, strlen(str)); |
| } |
| |
| static void o_addstr_with_NUL(o_string *o, const char *str) |
| { |
| o_addblock(o, str, strlen(str) + 1); |
| } |
| |
| #if !BB_MMU |
| static void nommu_addchr(o_string *o, int ch) |
| { |
| if (o) |
| o_addchr(o, ch); |
| } |
| #else |
| # define nommu_addchr(o, str) ((void)0) |
| #endif |
| |
| #if ENABLE_HUSH_MODE_X |
| static void x_mode_addchr(int ch) |
| { |
| o_addchr(&G.x_mode_buf, ch); |
| } |
| static void x_mode_addstr(const char *str) |
| { |
| o_addstr(&G.x_mode_buf, str); |
| } |
| static void x_mode_addblock(const char *str, int len) |
| { |
| o_addblock(&G.x_mode_buf, str, len); |
| } |
| static void x_mode_prefix(void) |
| { |
| int n = G.x_mode_depth; |
| do x_mode_addchr('+'); while (--n >= 0); |
| } |
| static void x_mode_flush(void) |
| { |
| int len = G.x_mode_buf.length; |
| if (len <= 0) |
| return; |
| if (G.x_mode_fd > 0) { |
| G.x_mode_buf.data[len] = '\n'; |
| full_write(G.x_mode_fd, G.x_mode_buf.data, len + 1); |
| } |
| G.x_mode_buf.length = 0; |
| } |
| #endif |
| |
| /* |
| * HUSH_BRACE_EXPANSION code needs corresponding quoting on variable expansion side. |
| * Currently, "v='{q,w}'; echo $v" erroneously expands braces in $v. |
| * Apparently, on unquoted $v bash still does globbing |
| * ("v='*.txt'; echo $v" prints all .txt files), |
| * but NOT brace expansion! Thus, there should be TWO independent |
| * quoting mechanisms on $v expansion side: one protects |
| * $v from brace expansion, and other additionally protects "$v" against globbing. |
| * We have only second one. |
| */ |
| |
| #if ENABLE_HUSH_BRACE_EXPANSION |
| # define MAYBE_BRACES "{}" |
| #else |
| # define MAYBE_BRACES "" |
| #endif |
| |
| /* My analysis of quoting semantics tells me that state information |
| * is associated with a destination, not a source. |
| */ |
| static void o_addqchr(o_string *o, int ch) |
| { |
| int sz = 1; |
| /* '-' is included because of this case: |
| * >filename0 >filename1 >filename9; v='-'; echo filename[0"$v"9] |
| */ |
| char *found = strchr("*?[-\\" MAYBE_BRACES, ch); |
| if (found) |
| sz++; |
| o_grow_by(o, sz); |
| if (found) { |
| o->data[o->length] = '\\'; |
| o->length++; |
| } |
| o->data[o->length] = ch; |
| o->length++; |
| o->data[o->length] = '\0'; |
| } |
| |
| static void o_addQchr(o_string *o, int ch) |
| { |
| int sz = 1; |
| if ((o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS) |
| && strchr("*?[-\\" MAYBE_BRACES, ch) |
| ) { |
| sz++; |
| o->data[o->length] = '\\'; |
| o->length++; |
| } |
| o_grow_by(o, sz); |
| o->data[o->length] = ch; |
| o->length++; |
| o->data[o->length] = '\0'; |
| } |
| |
| static void o_addqblock(o_string *o, const char *str, int len) |
| { |
| while (len) { |
| char ch; |
| int sz; |
| int ordinary_cnt = strcspn(str, "*?[-\\" MAYBE_BRACES); |
| if (ordinary_cnt > len) /* paranoia */ |
| ordinary_cnt = len; |
| o_addblock(o, str, ordinary_cnt); |
| if (ordinary_cnt == len) |
| return; /* NUL is already added by o_addblock */ |
| str += ordinary_cnt; |
| len -= ordinary_cnt + 1; /* we are processing + 1 char below */ |
| |
| ch = *str++; |
| sz = 1; |
| if (ch) { /* it is necessarily one of "*?[-\\" MAYBE_BRACES */ |
| sz++; |
| o->data[o->length] = '\\'; |
| o->length++; |
| } |
| o_grow_by(o, sz); |
| o->data[o->length] = ch; |
| o->length++; |
| } |
| o->data[o->length] = '\0'; |
| } |
| |
| static void o_addQblock(o_string *o, const char *str, int len) |
| { |
| if (!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)) { |
| o_addblock(o, str, len); |
| return; |
| } |
| o_addqblock(o, str, len); |
| } |
| |
| static void o_addQstr(o_string *o, const char *str) |
| { |
| o_addQblock(o, str, strlen(str)); |
| } |
| |
| /* A special kind of o_string for $VAR and `cmd` expansion. |
| * It contains char* list[] at the beginning, which is grown in 16 element |
| * increments. Actual string data starts at the next multiple of 16 * (char*). |
| * list[i] contains an INDEX (int!) into this string data. |
| * It means that if list[] needs to grow, data needs to be moved higher up |
| * but list[i]'s need not be modified. |
| * NB: remembering how many list[i]'s you have there is crucial. |
| * o_finalize_list() operation post-processes this structure - calculates |
| * and stores actual char* ptrs in list[]. Oh, it NULL terminates it as well. |
| */ |
| #if DEBUG_EXPAND || DEBUG_GLOB |
| static void debug_print_list(const char *prefix, o_string *o, int n) |
| { |
| char **list = (char**)o->data; |
| int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]); |
| int i = 0; |
| |
| indent(); |
| fdprintf(2, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d glob:%d quoted:%d escape:%d\n", |
| prefix, list, n, string_start, o->length, o->maxlen, |
| !!(o->o_expflags & EXP_FLAG_GLOB), |
| o->has_quoted_part, |
| !!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)); |
| while (i < n) { |
| indent(); |
| fdprintf(2, " list[%d]=%d '%s' %p\n", i, (int)(uintptr_t)list[i], |
| o->data + (int)(uintptr_t)list[i] + string_start, |
| o->data + (int)(uintptr_t)list[i] + string_start); |
| i++; |
| } |
| if (n) { |
| const char *p = o->data + (int)(uintptr_t)list[n - 1] + string_start; |
| indent(); |
| fdprintf(2, " total_sz:%ld\n", (long)((p + strlen(p) + 1) - o->data)); |
| } |
| } |
| #else |
| # define debug_print_list(prefix, o, n) ((void)0) |
| #endif |
| |
| /* n = o_save_ptr_helper(str, n) "starts new string" by storing an index value |
| * in list[n] so that it points past last stored byte so far. |
| * It returns n+1. */ |
| static int o_save_ptr_helper(o_string *o, int n) |
| { |
| char **list = (char**)o->data; |
| int string_start; |
| int string_len; |
| |
| if (!o->has_empty_slot) { |
| string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]); |
| string_len = o->length - string_start; |
| if (!(n & 0xf)) { /* 0, 0x10, 0x20...? */ |
| debug_printf_list("list[%d]=%d string_start=%d (growing)\n", n, string_len, string_start); |
| /* list[n] points to string_start, make space for 16 more pointers */ |
| o->maxlen += 0x10 * sizeof(list[0]); |
| o->data = xrealloc(o->data, o->maxlen + 1); |
| list = (char**)o->data; |
| memmove(list + n + 0x10, list + n, string_len); |
| /* |
| * expand_on_ifs() has a "previous argv[] ends in IFS?" |
| * check. (grep for -prev-ifs-check-). |
| * Ensure that argv[-1][last] is not garbage |
| * but zero bytes, to save index check there. |
| */ |
| list[n + 0x10 - 1] = 0; |
| o->length += 0x10 * sizeof(list[0]); |
| } else { |
| debug_printf_list("list[%d]=%d string_start=%d\n", |
| n, string_len, string_start); |
| } |
| } else { |
| /* We have empty slot at list[n], reuse without growth */ |
| string_start = ((n+1 + 0xf) & ~0xf) * sizeof(list[0]); /* NB: n+1! */ |
| string_len = o->length - string_start; |
| debug_printf_list("list[%d]=%d string_start=%d (empty slot)\n", |
| n, string_len, string_start); |
| o->has_empty_slot = 0; |
| } |
| o->has_quoted_part = 0; |
| list[n] = (char*)(uintptr_t)string_len; |
| return n + 1; |
| } |
| |
| /* "What was our last o_save_ptr'ed position (byte offset relative o->data)?" */ |
| static int o_get_last_ptr(o_string *o, int n) |
| { |
| char **list = (char**)o->data; |
| int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]); |
| |
| return ((int)(uintptr_t)list[n-1]) + string_start; |
| } |
| |
| /* |
| * Globbing routines. |
| * |
| * Most words in commands need to be globbed, even ones which are |
| * (single or double) quoted. This stems from the possiblity of |
| * constructs like "abc"* and 'abc'* - these should be globbed. |
| * Having a different code path for fully-quoted strings ("abc", |
| * 'abc') would only help performance-wise, but we still need |
| * code for partially-quoted strings. |
| * |
| * Unfortunately, if we want to match bash and ash behavior in all cases, |
| * the logic can't be "shell-syntax argument is first transformed |
| * to a string, then globbed, and if globbing does not match anything, |
| * it is used verbatim". Here are two examples where it fails: |
| * |
| * echo 'b\*'? |
| * |
| * The globbing can't be avoided (because of '?' at the end). |
| * The glob pattern is: b\\\*? - IOW, both \ and * are literals |
| * and are glob-escaped. If this does not match, bash/ash print b\*? |
| * - IOW: they "unbackslash" the glob pattern. |
| * Now, look at this: |
| * |
| * v='\\\*'; echo b$v? |
| * |
| * The glob pattern is the same here: b\\\*? - the unquoted $v expansion |
| * should be used as glob pattern with no changes. However, if glob |
| * does not match, bash/ash print b\\\*? - NOT THE SAME as first example! |
| * |
| * ash implements this by having an encoded representation of the word |
| * to glob, which IS NOT THE SAME as the glob pattern - it has more data. |
| * Glob pattern is derived from it. If glob fails, the decision what result |
| * should be is made using that encoded representation. Not glob pattern. |
| */ |
| |
| #if ENABLE_HUSH_BRACE_EXPANSION |
| /* There in a GNU extension, GLOB_BRACE, but it is not usable: |
| * first, it processes even {a} (no commas), second, |
| * I didn't manage to make it return strings when they don't match |
| * existing files. Need to re-implement it. |
| */ |
| |
| /* Helper */ |
| static int glob_needed(const char *s) |
| { |
| while (*s) { |
| if (*s == '\\') { |
| if (!s[1]) |
| return 0; |
| s += 2; |
| continue; |
| } |
| if (*s == '*' || *s == '[' || *s == '?' || *s == '{') |
| return 1; |
| s++; |
| } |
| return 0; |
| } |
| /* Return pointer to next closing brace or to comma */ |
| static const char *next_brace_sub(const char *cp) |
| { |
| unsigned depth = 0; |
| cp++; |
| while (*cp != '\0') { |
| if (*cp == '\\') { |
| if (*++cp == '\0') |
| break; |
| cp++; |
| continue; |
| } |
| if ((*cp == '}' && depth-- == 0) || (*cp == ',' && depth == 0)) |
| break; |
| if (*cp++ == '{') |
| depth++; |
| } |
| |
| return *cp != '\0' ? cp : NULL; |
| } |
| /* Recursive brace globber. Note: may garble pattern[]. */ |
| static int glob_brace(char *pattern, o_string *o, int n) |
| { |
| char *new_pattern_buf; |
| const char *begin; |
| const char *next; |
| const char *rest; |
| const char *p; |
| size_t rest_len; |
| |
| debug_printf_glob("glob_brace('%s')\n", pattern); |
| |
| begin = pattern; |
| while (1) { |
| if (*begin == '\0') |
| goto simple_glob; |
| if (*begin == '{') { |
| /* Find the first sub-pattern and at the same time |
| * find the rest after the closing brace */ |
| next = next_brace_sub(begin); |
| if (next == NULL) { |
| /* An illegal expression */ |
| goto simple_glob; |
| } |
| if (*next == '}') { |
| /* "{abc}" with no commas - illegal |
| * brace expr, disregard and skip it */ |
| begin = next + 1; |
| continue; |
| } |
| break; |
| } |
| if (*begin == '\\' && begin[1] != '\0') |
| begin++; |
| begin++; |
| } |
| debug_printf_glob("begin:%s\n", begin); |
| debug_printf_glob("next:%s\n", next); |
| |
| /* Now find the end of the whole brace expression */ |
| rest = next; |
| while (*rest != '}') { |
| rest = next_brace_sub(rest); |
| if (rest == NULL) { |
| /* An illegal expression */ |
| goto simple_glob; |
| } |
| debug_printf_glob("rest:%s\n", rest); |
| } |
| rest_len = strlen(++rest) + 1; |
| |
| /* We are sure the brace expression is well-formed */ |
| |
| /* Allocate working buffer large enough for our work */ |
| new_pattern_buf = xmalloc(strlen(pattern)); |
| |
| /* We have a brace expression. BEGIN points to the opening {, |
| * NEXT points past the terminator of the first element, and REST |
| * points past the final }. We will accumulate result names from |
| * recursive runs for each brace alternative in the buffer using |
| * GLOB_APPEND. */ |
| |
| p = begin + 1; |
| while (1) { |
| /* Construct the new glob expression */ |
| memcpy( |
| mempcpy( |
| mempcpy(new_pattern_buf, |
| /* We know the prefix for all sub-patterns */ |
| pattern, begin - pattern), |
| p, next - p), |
| rest, rest_len); |
| |
| /* Note: glob_brace() may garble new_pattern_buf[]. |
| * That's why we re-copy prefix every time (1st memcpy above). |
| */ |
| n = glob_brace(new_pattern_buf, o, n); |
| if (*next == '}') { |
| /* We saw the last entry */ |
| break; |
| } |
| p = next + 1; |
| next = next_brace_sub(next); |
| } |
| free(new_pattern_buf); |
| return n; |
| |
| simple_glob: |
| { |
| int gr; |
| glob_t globdata; |
| |
| memset(&globdata, 0, sizeof(globdata)); |
| gr = glob(pattern, 0, NULL, &globdata); |
| debug_printf_glob("glob('%s'):%d\n", pattern, gr); |
| if (gr != 0) { |
| if (gr == GLOB_NOMATCH) { |
| globfree(&globdata); |
| /* NB: garbles parameter */ |
| unbackslash(pattern); |
| o_addstr_with_NUL(o, pattern); |
| debug_printf_glob("glob pattern '%s' is literal\n", pattern); |
| return o_save_ptr_helper(o, n); |
| } |
| if (gr == GLOB_NOSPACE) |
| bb_die_memory_exhausted(); |
| /* GLOB_ABORTED? Only happens with GLOB_ERR flag, |
| * but we didn't specify it. Paranoia again. */ |
| bb_error_msg_and_die("glob error %d on '%s'", gr, pattern); |
| } |
| if (globdata.gl_pathv && globdata.gl_pathv[0]) { |
| char **argv = globdata.gl_pathv; |
| while (1) { |
| o_addstr_with_NUL(o, *argv); |
| n = o_save_ptr_helper(o, n); |
| argv++; |
| if (!*argv) |
| break; |
| } |
| } |
| globfree(&globdata); |
| } |
| return n; |
| } |
| /* Performs globbing on last list[], |
| * saving each result as a new list[]. |
| */ |
| static int perform_glob(o_string *o, int n) |
| { |
| char *pattern, *copy; |
| |
| debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data); |
| if (!o->data) |
| return o_save_ptr_helper(o, n); |
| pattern = o->data + o_get_last_ptr(o, n); |
| debug_printf_glob("glob pattern '%s'\n", pattern); |
| if (!glob_needed(pattern)) { |
| /* unbackslash last string in o in place, fix length */ |
| o->length = unbackslash(pattern) - o->data; |
| debug_printf_glob("glob pattern '%s' is literal\n", pattern); |
| return o_save_ptr_helper(o, n); |
| } |
| |
| copy = xstrdup(pattern); |
| /* "forget" pattern in o */ |
| o->length = pattern - o->data; |
| n = glob_brace(copy, o, n); |
| free(copy); |
| if (DEBUG_GLOB) |
| debug_print_list("perform_glob returning", o, n); |
| return n; |
| } |
| |
| #else /* !HUSH_BRACE_EXPANSION */ |
| |
| /* Helper */ |
| static int glob_needed(const char *s) |
| { |
| while (*s) { |
| if (*s == '\\') { |
| if (!s[1]) |
| return 0; |
| s += 2; |
| continue; |
| } |
| if (*s == '*' || *s == '[' || *s == '?') |
| return 1; |
| s++; |
| } |
| return 0; |
| } |
| /* Performs globbing on last list[], |
| * saving each result as a new list[]. |
| */ |
| static int perform_glob(o_string *o, int n) |
| { |
| glob_t globdata; |
| int gr; |
| char *pattern; |
| |
| debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data); |
| if (!o->data) |
| return o_save_ptr_helper(o, n); |
| pattern = o->data + o_get_last_ptr(o, n); |
| debug_printf_glob("glob pattern '%s'\n", pattern); |
| if (!glob_needed(pattern)) { |
| literal: |
| /* unbackslash last string in o in place, fix length */ |
| o->length = unbackslash(pattern) - o->data; |
| debug_printf_glob("glob pattern '%s' is literal\n", pattern); |
| return o_save_ptr_helper(o, n); |
| } |
| |
| memset(&globdata, 0, sizeof(globdata)); |
| /* Can't use GLOB_NOCHECK: it does not unescape the string. |
| * If we glob "*.\*" and don't find anything, we need |
| * to fall back to using literal "*.*", but GLOB_NOCHECK |
| * will return "*.\*"! |
| */ |
| gr = glob(pattern, 0, NULL, &globdata); |
| debug_printf_glob("glob('%s'):%d\n", pattern, gr); |
| if (gr != 0) { |
| if (gr == GLOB_NOMATCH) { |
| globfree(&globdata); |
| goto literal; |
| } |
| if (gr == GLOB_NOSPACE) |
| bb_die_memory_exhausted(); |
| /* GLOB_ABORTED? Only happens with GLOB_ERR flag, |
| * but we didn't specify it. Paranoia again. */ |
| bb_error_msg_and_die("glob error %d on '%s'", gr, pattern); |
| } |
| if (globdata.gl_pathv && globdata.gl_pathv[0]) { |
| char **argv = globdata.gl_pathv; |
| /* "forget" pattern in o */ |
| o->length = pattern - o->data; |
| while (1) { |
| o_addstr_with_NUL(o, *argv); |
| n = o_save_ptr_helper(o, n); |
| argv++; |
| if (!*argv) |
| break; |
| } |
| } |
| globfree(&globdata); |
| if (DEBUG_GLOB) |
| debug_print_list("perform_glob returning", o, n); |
| return n; |
| } |
| |
| #endif /* !HUSH_BRACE_EXPANSION */ |
| |
| /* If o->o_expflags & EXP_FLAG_GLOB, glob the string so far remembered. |
| * Otherwise, just finish current list[] and start new */ |
| static int o_save_ptr(o_string *o, int n) |
| { |
| if (o->o_expflags & EXP_FLAG_GLOB) { |
| /* If o->has_empty_slot, list[n] was already globbed |
| * (if it was requested back then when it was filled) |
| * so don't do that again! */ |
| if (!o->has_empty_slot) |
| return perform_glob(o, n); /* o_save_ptr_helper is inside */ |
| } |
| return o_save_ptr_helper(o, n); |
| } |
| |
| /* "Please convert list[n] to real char* ptrs, and NULL terminate it." */ |
| static char **o_finalize_list(o_string *o, int n) |
| { |
| char **list; |
| int string_start; |
| |
| if (DEBUG_EXPAND) |
| debug_print_list("finalized", o, n); |
| debug_printf_expand("finalized n:%d\n", n); |
| list = (char**)o->data; |
| string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]); |
| list[--n] = NULL; |
| while (n) { |
| n--; |
| list[n] = o->data + (int)(uintptr_t)list[n] + string_start; |
| } |
| return list; |
| } |
| |
| static void free_pipe_list(struct pipe *pi); |
| |
| /* Returns pi->next - next pipe in the list */ |
| static struct pipe *free_pipe(struct pipe *pi) |
| { |
| struct pipe *next; |
| int i; |
| |
| debug_printf_clean("free_pipe (pid %d)\n", getpid()); |
| for (i = 0; i < pi->num_cmds; i++) { |
| struct command *command; |
| struct redir_struct *r, *rnext; |
| |
| command = &pi->cmds[i]; |
| debug_printf_clean(" command %d:\n", i); |
| if (command->argv) { |
| if (DEBUG_CLEAN) { |
| int a; |
| char **p; |
| for (a = 0, p = command->argv; *p; a++, p++) { |
| debug_printf_clean(" argv[%d] = %s\n", a, *p); |
| } |
| } |
| free_strings(command->argv); |
| //command->argv = NULL; |
| } |
| /* not "else if": on syntax error, we may have both! */ |
| if (command->group) { |
| debug_printf_clean(" begin group (cmd_type:%d)\n", |
| command->cmd_type); |
| free_pipe_list(command->group); |
| debug_printf_clean(" end group\n"); |
| //command->group = NULL; |
| } |
| /* else is crucial here. |
| * If group != NULL, child_func is meaningless */ |
| #if ENABLE_HUSH_FUNCTIONS |
| else if (command->child_func) { |
| debug_printf_exec("cmd %p releases child func at %p\n", command, command->child_func); |
| command->child_func->parent_cmd = NULL; |
| } |
| #endif |
| #if !BB_MMU |
| free(command->group_as_string); |
| //command->group_as_string = NULL; |
| #endif |
| for (r = command->redirects; r; r = rnext) { |
| debug_printf_clean(" redirect %d%s", |
| r->rd_fd, redir_table[r->rd_type].descrip); |
| /* guard against the case >$FOO, where foo is unset or blank */ |
| if (r->rd_filename) { |
| debug_printf_clean(" fname:'%s'\n", r->rd_filename); |
| free(r->rd_filename); |
| //r->rd_filename = NULL; |
| } |
| debug_printf_clean(" rd_dup:%d\n", r->rd_dup); |
| rnext = r->next; |
| free(r); |
| } |
| //command->redirects = NULL; |
| } |
| free(pi->cmds); /* children are an array, they get freed all at once */ |
| //pi->cmds = NULL; |
| #if ENABLE_HUSH_JOB |
| free(pi->cmdtext); |
| //pi->cmdtext = NULL; |
| #endif |
| |
| next = pi->next; |
| free(pi); |
| return next; |
| } |
| |
| static void free_pipe_list(struct pipe *pi) |
| { |
| while (pi) { |
| #if HAS_KEYWORDS |
| debug_printf_clean("pipe reserved word %d\n", pi->res_word); |
| #endif |
| debug_printf_clean("pipe followup code %d\n", pi->followup); |
| pi = free_pipe(pi); |
| } |
| } |
| |
| |
| /*** Parsing routines ***/ |
| |
| #ifndef debug_print_tree |
| static void debug_print_tree(struct pipe *pi, int lvl) |
| { |
| static const char *const PIPE[] = { |
| [PIPE_SEQ] = "SEQ", |
| [PIPE_AND] = "AND", |
| [PIPE_OR ] = "OR" , |
| [PIPE_BG ] = "BG" , |
| }; |
| static const char *RES[] = { |
| [RES_NONE ] = "NONE" , |
| # if ENABLE_HUSH_IF |
| [RES_IF ] = "IF" , |
| [RES_THEN ] = "THEN" , |
| [RES_ELIF ] = "ELIF" , |
| [RES_ELSE ] = "ELSE" , |
| [RES_FI ] = "FI" , |
| # endif |
| # if ENABLE_HUSH_LOOPS |
| [RES_FOR ] = "FOR" , |
| [RES_WHILE] = "WHILE", |
| [RES_UNTIL] = "UNTIL", |
| [RES_DO ] = "DO" , |
| [RES_DONE ] = "DONE" , |
| # endif |
| # if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE |
| [RES_IN ] = "IN" , |
| # endif |
| # if ENABLE_HUSH_CASE |
| [RES_CASE ] = "CASE" , |
| [RES_CASE_IN ] = "CASE_IN" , |
| [RES_MATCH] = "MATCH", |
| [RES_CASE_BODY] = "CASE_BODY", |
| [RES_ESAC ] = "ESAC" , |
| # endif |
| [RES_XXXX ] = "XXXX" , |
| [RES_SNTX ] = "SNTX" , |
| }; |
| static const char *const CMDTYPE[] = { |
| "{}", |
| "()", |
| "[noglob]", |
| # if ENABLE_HUSH_FUNCTIONS |
| "func()", |
| # endif |
| }; |
| |
| int pin, prn; |
| |
| pin = 0; |
| while (pi) { |
| fdprintf(2, "%*spipe %d #cmds:%d %sres_word=%s followup=%d %s\n", |
| lvl*2, "", |
| pin, |
| pi->num_cmds, |
| (IF_HAS_KEYWORDS(pi->pi_inverted ? "! " :) ""), |
| RES[pi->res_word], |
| pi->followup, PIPE[pi->followup] |
| ); |
| prn = 0; |
| while (prn < pi->num_cmds) { |
| struct command *command = &pi->cmds[prn]; |
| char **argv = command->argv; |
| |
| fdprintf(2, "%*s cmd %d assignment_cnt:%d", |
| lvl*2, "", prn, |
| command->assignment_cnt); |
| # if ENABLE_HUSH_LINENO_VAR |
| fdprintf(2, " LINENO:%u", command->lineno); |
| # endif |
| if (command->group) { |
| fdprintf(2, " group %s: (argv=%p)%s%s\n", |
| CMDTYPE[command->cmd_type], |
| argv |
| # if !BB_MMU |
| , " group_as_string:", command->group_as_string |
| # else |
| , "", "" |
| # endif |
| ); |
| debug_print_tree(command->group, lvl+1); |
| prn++; |
| continue; |
| } |
| if (argv) while (*argv) { |
| fdprintf(2, " '%s'", *argv); |
| argv++; |
| } |
| if (command->redirects) |
| fdprintf(2, " {redir}"); |
| fdprintf(2, "\n"); |
| prn++; |
| } |
| pi = pi->next; |
| pin++; |
| } |
| } |
| #endif /* debug_print_tree */ |
| |
| static struct pipe *new_pipe(void) |
| { |
| struct pipe *pi; |
| pi = xzalloc(sizeof(struct pipe)); |
| /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */ |
| return pi; |
| } |
| |
| /* Command (member of a pipe) is complete, or we start a new pipe |
| * if ctx->command is NULL. |
| * No errors possible here. |
| */ |
| static int done_command(struct parse_context *ctx) |
| { |
| /* The command is really already in the pipe structure, so |
| * advance the pipe counter and make a new, null command. */ |
| struct pipe *pi = ctx->pipe; |
| struct command *command = ctx->command; |
| |
| #if 0 /* Instead we emit error message at run time */ |
| if (ctx->pending_redirect) { |
| /* For example, "cmd >" (no filename to redirect to) */ |
| syntax_error("invalid redirect"); |
| ctx->pending_redirect = NULL; |
| } |
| #endif |
| |
| if (command) { |
| if (IS_NULL_CMD(command)) { |
| debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds); |
| goto clear_and_ret; |
| } |
| pi->num_cmds++; |
| debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds); |
| //debug_print_tree(ctx->list_head, 20); |
| } else { |
| debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds); |
| } |
| |
| /* Only real trickiness here is that the uncommitted |
| * command structure is not counted in pi->num_cmds. */ |
| pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1)); |
| ctx->command = command = &pi->cmds[pi->num_cmds]; |
| clear_and_ret: |
| memset(command, 0, sizeof(*command)); |
| #if ENABLE_HUSH_LINENO_VAR |
| command->lineno = G.parse_lineno; |
| debug_printf_parse("command->lineno = G.parse_lineno (%u)\n", G.parse_lineno); |
| #endif |
| return pi->num_cmds; /* used only for 0/nonzero check */ |
| } |
| |
| static void done_pipe(struct parse_context *ctx, pipe_style type) |
| { |
| int not_null; |
| |
| debug_printf_parse("done_pipe entered, followup %d\n", type); |
| /* Close previous command */ |
| not_null = done_command(ctx); |
| #if HAS_KEYWORDS |
| ctx->pipe->pi_inverted = ctx->ctx_inverted; |
| ctx->ctx_inverted = 0; |
| ctx->pipe->res_word = ctx->ctx_res_w; |
| #endif |
| if (type == PIPE_BG && ctx->list_head != ctx->pipe) { |
| /* Necessary since && and || have precedence over &: |
| * "cmd1 && cmd2 &" must spawn both cmds, not only cmd2, |
| * in a backgrounded subshell. |
| */ |
| struct pipe *pi; |
| struct command *command; |
| |
| /* Is this actually this construct, all pipes end with && or ||? */ |
| pi = ctx->list_head; |
| while (pi != ctx->pipe) { |
| if (pi->followup != PIPE_AND && pi->followup != PIPE_OR) |
| goto no_conv; |
| pi = pi->next; |
| } |
| |
| debug_printf_parse("BG with more than one pipe, converting to { p1 &&...pN; } &\n"); |
| pi->followup = PIPE_SEQ; /* close pN _not_ with "&"! */ |
| pi = xzalloc(sizeof(*pi)); |
| pi->followup = PIPE_BG; |
| pi->num_cmds = 1; |
| pi->cmds = xzalloc(sizeof(pi->cmds[0])); |
| command = &pi->cmds[0]; |
| if (CMD_NORMAL != 0) /* "if xzalloc didn't do that already" */ |
| command->cmd_type = CMD_NORMAL; |
| command->group = ctx->list_head; |
| #if !BB_MMU |
| command->group_as_string = xstrndup( |
| ctx->as_string.data, |
| ctx->as_string.length - 1 /* do not copy last char, "&" */ |
| ); |
| #endif |
| /* Replace all pipes in ctx with one newly created */ |
| ctx->list_head = ctx->pipe = pi; |
| /* for cases like "cmd && &", do not be tricked by last command |
| * being null - the entire {...} & is NOT null! */ |
| not_null = 1; |
| } else { |
| no_conv: |
| ctx->pipe->followup = type; |
| } |
| |
| /* Without this check, even just <enter> on command line generates |
| * tree of three NOPs (!). Which is harmless but annoying. |
| * IOW: it is safe to do it unconditionally. */ |
| if (not_null |
| #if ENABLE_HUSH_IF |
| || ctx->ctx_res_w == RES_FI |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| || ctx->ctx_res_w == RES_DONE |
| || ctx->ctx_res_w == RES_FOR |
| || ctx->ctx_res_w == RES_IN |
| #endif |
| #if ENABLE_HUSH_CASE |
| || ctx->ctx_res_w == RES_ESAC |
| #endif |
| ) { |
| struct pipe *new_p; |
| debug_printf_parse("done_pipe: adding new pipe: " |
| "not_null:%d ctx->ctx_res_w:%d\n", |
| not_null, ctx->ctx_res_w); |
| new_p = new_pipe(); |
| ctx->pipe->next = new_p; |
| ctx->pipe = new_p; |
| /* RES_THEN, RES_DO etc are "sticky" - |
| * they remain set for pipes inside if/while. |
| * This is used to control execution. |
| * RES_FOR and RES_IN are NOT sticky (needed to support |
| * cases where variable or value happens to match a keyword): |
| */ |
| #if ENABLE_HUSH_LOOPS |
| if (ctx->ctx_res_w == RES_FOR |
| || ctx->ctx_res_w == RES_IN) |
| ctx->ctx_res_w = RES_NONE; |
| #endif |
| #if ENABLE_HUSH_CASE |
| if (ctx->ctx_res_w == RES_MATCH) |
| ctx->ctx_res_w = RES_CASE_BODY; |
| if (ctx->ctx_res_w == RES_CASE) |
| ctx->ctx_res_w = RES_CASE_IN; |
| #endif |
| ctx->command = NULL; /* trick done_command below */ |
| /* Create the memory for command, roughly: |
| * ctx->pipe->cmds = new struct command; |
| * ctx->command = &ctx->pipe->cmds[0]; |
| */ |
| done_command(ctx); |
| //debug_print_tree(ctx->list_head, 10); |
| } |
| debug_printf_parse("done_pipe return\n"); |
| } |
| |
| static void initialize_context(struct parse_context *ctx) |
| { |
| memset(ctx, 0, sizeof(*ctx)); |
| if (MAYBE_ASSIGNMENT != 0) |
| ctx->is_assignment = MAYBE_ASSIGNMENT; |
| ctx->pipe = ctx->list_head = new_pipe(); |
| /* Create the memory for command, roughly: |
| * ctx->pipe->cmds = new struct command; |
| * ctx->command = &ctx->pipe->cmds[0]; |
| */ |
| done_command(ctx); |
| } |
| |
| /* If a reserved word is found and processed, parse context is modified |
| * and 1 is returned. |
| */ |
| #if HAS_KEYWORDS |
| struct reserved_combo { |
| char literal[6]; |
| unsigned char res; |
| unsigned char assignment_flag; |
| uint32_t flag; |
| }; |
| enum { |
| FLAG_END = (1 << RES_NONE ), |
| # if ENABLE_HUSH_IF |
| FLAG_IF = (1 << RES_IF ), |
| FLAG_THEN = (1 << RES_THEN ), |
| FLAG_ELIF = (1 << RES_ELIF ), |
| FLAG_ELSE = (1 << RES_ELSE ), |
| FLAG_FI = (1 << RES_FI ), |
| # endif |
| # if ENABLE_HUSH_LOOPS |
| FLAG_FOR = (1 << RES_FOR ), |
| FLAG_WHILE = (1 << RES_WHILE), |
| FLAG_UNTIL = (1 << RES_UNTIL), |
| FLAG_DO = (1 << RES_DO ), |
| FLAG_DONE = (1 << RES_DONE ), |
| FLAG_IN = (1 << RES_IN ), |
| # endif |
| # if ENABLE_HUSH_CASE |
| FLAG_MATCH = (1 << RES_MATCH), |
| FLAG_ESAC = (1 << RES_ESAC ), |
| # endif |
| FLAG_START = (1 << RES_XXXX ), |
| }; |
| |
| static const struct reserved_combo* match_reserved_word(o_string *word) |
| { |
| /* Mostly a list of accepted follow-up reserved words. |
| * FLAG_END means we are done with the sequence, and are ready |
| * to turn the compound list into a command. |
| * FLAG_START means the word must start a new compound list. |
| */ |
| static const struct reserved_combo reserved_list[] ALIGN4 = { |
| # if ENABLE_HUSH_IF |
| { "!", RES_NONE, NOT_ASSIGNMENT , 0 }, |
| { "if", RES_IF, MAYBE_ASSIGNMENT, FLAG_THEN | FLAG_START }, |
| { "then", RES_THEN, MAYBE_ASSIGNMENT, FLAG_ELIF | FLAG_ELSE | FLAG_FI }, |
| { "elif", RES_ELIF, MAYBE_ASSIGNMENT, FLAG_THEN }, |
| { "else", RES_ELSE, MAYBE_ASSIGNMENT, FLAG_FI }, |
| { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END }, |
| # endif |
| # if ENABLE_HUSH_LOOPS |
| { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START }, |
| { "while", RES_WHILE, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START }, |
| { "until", RES_UNTIL, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START }, |
| { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO }, |
| { "do", RES_DO, MAYBE_ASSIGNMENT, FLAG_DONE }, |
| { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END }, |
| # endif |
| # if ENABLE_HUSH_CASE |
| { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START }, |
| { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END }, |
| # endif |
| }; |
| const struct reserved_combo *r; |
| |
| for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) { |
| if (strcmp(word->data, r->literal) == 0) |
| return r; |
| } |
| return NULL; |
| } |
| /* Return NULL: not a keyword, else: keyword |
| */ |
| static const struct reserved_combo* reserved_word(struct parse_context *ctx) |
| { |
| # if ENABLE_HUSH_CASE |
| static const struct reserved_combo reserved_match = { |
| "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC |
| }; |
| # endif |
| const struct reserved_combo *r; |
| |
| if (ctx->word.has_quoted_part) |
| return 0; |
| r = match_reserved_word(&ctx->word); |
| if (!r) |
| return r; /* NULL */ |
| |
| debug_printf("found reserved word %s, res %d\n", r->literal, r->res); |
| # if ENABLE_HUSH_CASE |
| if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE_IN) { |
| /* "case word IN ..." - IN part starts first MATCH part */ |
| r = &reserved_match; |
| } else |
| # endif |
| if (r->flag == 0) { /* '!' */ |
| if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */ |
| syntax_error("! ! command"); |
| ctx->ctx_res_w = RES_SNTX; |
| } |
| ctx->ctx_inverted = 1; |
| return r; |
| } |
| if (r->flag & FLAG_START) { |
| struct parse_context *old; |
| |
| old = xmemdup(ctx, sizeof(*ctx)); |
| debug_printf_parse("push stack %p\n", old); |
| initialize_context(ctx); |
| ctx->stack = old; |
| } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) { |
| syntax_error_at(ctx->word.data); |
| ctx->ctx_res_w = RES_SNTX; |
| return r; |
| } else { |
| /* "{...} fi" is ok. "{...} if" is not |
| * Example: |
| * if { echo foo; } then { echo bar; } fi */ |
| if (ctx->command->group) |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| |
| ctx->ctx_res_w = r->res; |
| ctx->old_flag = r->flag; |
| ctx->is_assignment = r->assignment_flag; |
| debug_printf_parse("ctx->is_assignment='%s'\n", assignment_flag[ctx->is_assignment]); |
| |
| if (ctx->old_flag & FLAG_END) { |
| struct parse_context *old; |
| |
| done_pipe(ctx, PIPE_SEQ); |
| debug_printf_parse("pop stack %p\n", ctx->stack); |
| old = ctx->stack; |
| old->command->group = ctx->list_head; |
| old->command->cmd_type = CMD_NORMAL; |
| # if !BB_MMU |
| /* At this point, the compound command's string is in |
| * ctx->as_string... except for the leading keyword! |
| * Consider this example: "echo a | if true; then echo a; fi" |
| * ctx->as_string will contain "true; then echo a; fi", |
| * with "if " remaining in old->as_string! |
| */ |
| { |
| char *str; |
| int len = old->as_string.length; |
| /* Concatenate halves */ |
| o_addstr(&old->as_string, ctx->as_string.data); |
| o_free(&ctx->as_string); |
| /* Find where leading keyword starts in first half */ |
| str = old->as_string.data + len; |
| if (str > old->as_string.data) |
| str--; /* skip whitespace after keyword */ |
| while (str > old->as_string.data && isalpha(str[-1])) |
| str--; |
| /* Ugh, we're done with this horrid hack */ |
| old->command->group_as_string = xstrdup(str); |
| debug_printf_parse("pop, remembering as:'%s'\n", |
| old->command->group_as_string); |
| } |
| # endif |
| *ctx = *old; /* physical copy */ |
| free(old); |
| } |
| return r; |
| } |
| #endif /* HAS_KEYWORDS */ |
| |
| /* Word is complete, look at it and update parsing context. |
| * Normal return is 0. Syntax errors return 1. |
| * Note: on return, word is reset, but not o_free'd! |
| */ |
| static int done_word(struct parse_context *ctx) |
| { |
| struct command *command = ctx->command; |
| |
| debug_printf_parse("done_word entered: '%s' %p\n", ctx->word.data, command); |
| if (ctx->word.length == 0 && !ctx->word.has_quoted_part) { |
| debug_printf_parse("done_word return 0: true null, ignored\n"); |
| return 0; |
| } |
| |
| if (ctx->pending_redirect) { |
| /* We do not glob in e.g. >*.tmp case. bash seems to glob here |
| * only if run as "bash", not "sh" */ |
| /* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html |
| * "2.7 Redirection |
| * If the redirection operator is "<<" or "<<-", the word |
| * that follows the redirection operator shall be |
| * subjected to quote removal; it is unspecified whether |
| * any of the other expansions occur. For the other |
| * redirection operators, the word that follows the |
| * redirection operator shall be subjected to tilde |
| * expansion, parameter expansion, command substitution, |
| * arithmetic expansion, and quote removal. |
| * Pathname expansion shall not be performed |
| * on the word by a non-interactive shell; an interactive |
| * shell may perform it, but shall do so only when |
| * the expansion would result in one word." |
| */ |
| //bash does not do parameter/command substitution or arithmetic expansion |
| //for _heredoc_ redirection word: these constructs look for exact eof marker |
| // as written: |
| // <<EOF$t |
| // <<EOF$((1)) |
| // <<EOF`true` [this case also makes heredoc "quoted", a-la <<"EOF". Probably bash-4.3.43 bug] |
| |
| ctx->pending_redirect->rd_filename = xstrdup(ctx->word.data); |
| /* Cater for >\file case: |
| * >\a creates file a; >\\a, >"\a", >"\\a" create file \a |
| * Same with heredocs: |
| * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H |
| */ |
| if (ctx->pending_redirect->rd_type == REDIRECT_HEREDOC) { |
| unbackslash(ctx->pending_redirect->rd_filename); |
| /* Is it <<"HEREDOC"? */ |
| if (ctx->word.has_quoted_part) { |
| ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED; |
| } |
| } |
| debug_printf_parse("word stored in rd_filename: '%s'\n", ctx->word.data); |
| ctx->pending_redirect = NULL; |
| } else { |
| #if HAS_KEYWORDS |
| # if ENABLE_HUSH_CASE |
| if (ctx->ctx_dsemicolon |
| && strcmp(ctx->word.data, "esac") != 0 /* not "... pattern) cmd;; esac" */ |
| ) { |
| /* already done when ctx_dsemicolon was set to 1: */ |
| /* ctx->ctx_res_w = RES_MATCH; */ |
| ctx->ctx_dsemicolon = 0; |
| } else |
| # endif |
| # if defined(CMD_TEST2_SINGLEWORD_NOGLOB) |
| if (command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB |
| && strcmp(ctx->word.data, "]]") == 0 |
| ) { |
| /* allow "[[ ]] >file" etc */ |
| command->cmd_type = CMD_SINGLEWORD_NOGLOB; |
| } else |
| # endif |
| if (!command->argv /* if it's the first word... */ |
| # if ENABLE_HUSH_LOOPS |
| && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */ |
| && ctx->ctx_res_w != RES_IN |
| # endif |
| # if ENABLE_HUSH_CASE |
| && ctx->ctx_res_w != RES_CASE |
| # endif |
| ) { |
| const struct reserved_combo *reserved; |
| reserved = reserved_word(ctx); |
| debug_printf_parse("checking for reserved-ness: %d\n", !!reserved); |
| if (reserved) { |
| # if ENABLE_HUSH_LINENO_VAR |
| /* Case: |
| * "while ...; do |
| * cmd ..." |
| * If we don't close the pipe _now_, immediately after "do", lineno logic |
| * sees "cmd" as starting at "do" - i.e., at the previous line. |
| */ |
| if (0 |
| IF_HUSH_IF(|| reserved->res == RES_THEN) |
| IF_HUSH_IF(|| reserved->res == RES_ELIF) |
| IF_HUSH_IF(|| reserved->res == RES_ELSE) |
| IF_HUSH_LOOPS(|| reserved->res == RES_DO) |
| ) { |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| # endif |
| o_reset_to_empty_unquoted(&ctx->word); |
| debug_printf_parse("done_word return %d\n", |
| (ctx->ctx_res_w == RES_SNTX)); |
| return (ctx->ctx_res_w == RES_SNTX); |
| } |
| # if defined(CMD_TEST2_SINGLEWORD_NOGLOB) |
| if (strcmp(ctx->word.data, "[[") == 0) { |
| command->cmd_type = CMD_TEST2_SINGLEWORD_NOGLOB; |
| } else |
| # endif |
| # if defined(CMD_SINGLEWORD_NOGLOB) |
| if (0 |
| /* In bash, local/export/readonly are special, args |
| * are assignments and therefore expansion of them |
| * should be "one-word" expansion: |
| * $ export i=`echo 'a b'` # one arg: "i=a b" |
| * compare with: |
| * $ ls i=`echo 'a b'` # two args: "i=a" and "b" |
| * ls: cannot access i=a: No such file or directory |
| * ls: cannot access b: No such file or directory |
| * Note: bash 3.2.33(1) does this only if export word |
| * itself is not quoted: |
| * $ export i=`echo 'aaa bbb'`; echo "$i" |
| * aaa bbb |
| * $ "export" i=`echo 'aaa bbb'`; echo "$i" |
| * aaa |
| */ |
| IF_HUSH_LOCAL( || strcmp(ctx->word.data, "local") == 0) |
| IF_HUSH_EXPORT( || strcmp(ctx->word.data, "export") == 0) |
| IF_HUSH_READONLY(|| strcmp(ctx->word.data, "readonly") == 0) |
| ) { |
| command->cmd_type = CMD_SINGLEWORD_NOGLOB; |
| } |
| # else |
| { /* empty block to pair "if ... else" */ } |
| # endif |
| } |
| #endif /* HAS_KEYWORDS */ |
| |
| if (command->group) { |
| /* "{ echo foo; } echo bar" - bad */ |
| syntax_error_at(ctx->word.data); |
| debug_printf_parse("done_word return 1: syntax error, " |
| "groups and arglists don't mix\n"); |
| return 1; |
| } |
| |
| /* If this word wasn't an assignment, next ones definitely |
| * can't be assignments. Even if they look like ones. */ |
| if (ctx->is_assignment != DEFINITELY_ASSIGNMENT |
| && ctx->is_assignment != WORD_IS_KEYWORD |
| ) { |
| ctx->is_assignment = NOT_ASSIGNMENT; |
| } else { |
| if (ctx->is_assignment == DEFINITELY_ASSIGNMENT) { |
| command->assignment_cnt++; |
| debug_printf_parse("++assignment_cnt=%d\n", command->assignment_cnt); |
| } |
| debug_printf_parse("ctx->is_assignment was:'%s'\n", assignment_flag[ctx->is_assignment]); |
| ctx->is_assignment = MAYBE_ASSIGNMENT; |
| } |
| debug_printf_parse("ctx->is_assignment='%s'\n", assignment_flag[ctx->is_assignment]); |
| command->argv = add_string_to_strings(command->argv, xstrdup(ctx->word.data)); |
| debug_print_strings("word appended to argv", command->argv); |
| } |
| |
| #if ENABLE_HUSH_LOOPS |
| if (ctx->ctx_res_w == RES_FOR) { |
| if (ctx->word.has_quoted_part |
| || endofname(command->argv[0])[0] != '\0' |
| ) { |
| /* bash says just "not a valid identifier" */ |
| syntax_error("bad variable name in for"); |
| return 1; |
| } |
| /* Force FOR to have just one word (variable name) */ |
| /* NB: basically, this makes hush see "for v in ..." |
| * syntax as if it is "for v; in ...". FOR and IN become |
| * two pipe structs in parse tree. */ |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| #endif |
| #if ENABLE_HUSH_CASE |
| /* Force CASE to have just one word */ |
| if (ctx->ctx_res_w == RES_CASE) { |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| #endif |
| |
| o_reset_to_empty_unquoted(&ctx->word); |
| |
| debug_printf_parse("done_word return 0\n"); |
| return 0; |
| } |
| |
| |
| /* Peek ahead in the input to find out if we have a "&n" construct, |
| * as in "2>&1", that represents duplicating a file descriptor. |
| * Return: |
| * REDIRFD_CLOSE if >&- "close fd" construct is seen, |
| * REDIRFD_SYNTAX_ERR if syntax error, |
| * REDIRFD_TO_FILE if no & was seen, |
| * or the number found. |
| */ |
| #if BB_MMU |
| #define parse_redir_right_fd(as_string, input) \ |
| parse_redir_right_fd(input) |
| #endif |
| static int parse_redir_right_fd(o_string *as_string, struct in_str *input) |
| { |
| int ch, d, ok; |
| |
| ch = i_peek(input); |
| if (ch != '&') |
| return REDIRFD_TO_FILE; |
| |
| ch = i_getch(input); /* get the & */ |
| nommu_addchr(as_string, ch); |
| ch = i_peek(input); |
| if (ch == '-') { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| return REDIRFD_CLOSE; |
| } |
| d = 0; |
| ok = 0; |
| while (ch != EOF && isdigit(ch)) { |
| d = d*10 + (ch-'0'); |
| ok = 1; |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| ch = i_peek(input); |
| } |
| if (ok) return d; |
| |
| //TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2) |
| |
| bb_simple_error_msg("ambiguous redirect"); |
| return REDIRFD_SYNTAX_ERR; |
| } |
| |
| /* Return code is 0 normal, 1 if a syntax error is detected |
| */ |
| static int parse_redirect(struct parse_context *ctx, |
| int fd, |
| redir_type style, |
| struct in_str *input) |
| { |
| struct command *command = ctx->command; |
| struct redir_struct *redir; |
| struct redir_struct **redirp; |
| int dup_num; |
| |
| dup_num = REDIRFD_TO_FILE; |
| if (style != REDIRECT_HEREDOC) { |
| /* Check for a '>&1' type redirect */ |
| dup_num = parse_redir_right_fd(&ctx->as_string, input); |
| if (dup_num == REDIRFD_SYNTAX_ERR) |
| return 1; |
| } else { |
| int ch = i_peek_and_eat_bkslash_nl(input); |
| dup_num = (ch == '-'); /* HEREDOC_SKIPTABS bit is 1 */ |
| if (dup_num) { /* <<-... */ |
| ch = i_getch(input); |
| nommu_addchr(&ctx->as_string, ch); |
| ch = i_peek(input); |
| } |
| } |
| |
| if (style == REDIRECT_OVERWRITE && dup_num == REDIRFD_TO_FILE) { |
| int ch = i_peek_and_eat_bkslash_nl(input); |
| if (ch == '|') { |
| /* >|FILE redirect ("clobbering" >). |
| * Since we do not support "set -o noclobber" yet, |
| * >| and > are the same for now. Just eat |. |
| */ |
| ch = i_getch(input); |
| nommu_addchr(&ctx->as_string, ch); |
| } |
| } |
| |
| /* Create a new redir_struct and append it to the linked list */ |
| redirp = &command->redirects; |
| while ((redir = *redirp) != NULL) { |
| redirp = &(redir->next); |
| } |
| *redirp = redir = xzalloc(sizeof(*redir)); |
| /* redir->next = NULL; */ |
| /* redir->rd_filename = NULL; */ |
| redir->rd_type = style; |
| redir->rd_fd = (fd == -1) ? redir_table[style].default_fd : fd; |
| |
| debug_printf_parse("redirect type %d %s\n", redir->rd_fd, |
| redir_table[style].descrip); |
| |
| redir->rd_dup = dup_num; |
| if (style != REDIRECT_HEREDOC && dup_num != REDIRFD_TO_FILE) { |
| /* Erik had a check here that the file descriptor in question |
| * is legit; I postpone that to "run time" |
| * A "-" representation of "close me" shows up as a -3 here */ |
| debug_printf_parse("duplicating redirect '%d>&%d'\n", |
| redir->rd_fd, redir->rd_dup); |
| } else { |
| #if 0 /* Instead we emit error message at run time */ |
| if (ctx->pending_redirect) { |
| /* For example, "cmd > <file" */ |
| syntax_error("invalid redirect"); |
| } |
| #endif |
| /* Set ctx->pending_redirect, so we know what to do at the |
| * end of the next parsed word. */ |
| ctx->pending_redirect = redir; |
| } |
| return 0; |
| } |
| |
| /* If a redirect is immediately preceded by a number, that number is |
| * supposed to tell which file descriptor to redirect. This routine |
| * looks for such preceding numbers. In an ideal world this routine |
| * needs to handle all the following classes of redirects... |
| * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo |
| * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo |
| * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo |
| * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo |
| * |
| * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html |
| * "2.7 Redirection |
| * ... If n is quoted, the number shall not be recognized as part of |
| * the redirection expression. For example: |
| * echo \2>a |
| * writes the character 2 into file a" |
| * We are getting it right by setting ->has_quoted_part on any \<char> |
| * |
| * A -1 return means no valid number was found, |
| * the caller should use the appropriate default for this redirection. |
| */ |
| static int redirect_opt_num(o_string *o) |
| { |
| int num; |
| |
| if (o->data == NULL) |
| return -1; |
| num = bb_strtou(o->data, NULL, 10); |
| if (errno || num < 0) |
| return -1; |
| o_reset_to_empty_unquoted(o); |
| return num; |
| } |
| |
| #if BB_MMU |
| #define fetch_till_str(as_string, input, word, skip_tabs) \ |
| fetch_till_str(input, word, skip_tabs) |
| #endif |
| static char *fetch_till_str(o_string *as_string, |
| struct in_str *input, |
| const char *word, |
| int heredoc_flags) |
| { |
| o_string heredoc = NULL_O_STRING; |
| unsigned past_EOL; |
| int prev = 0; /* not \ */ |
| int ch; |
| |
| /* Starting with "" is necessary for this case: |
| * cat <<EOF |
| * |
| * xxx |
| * EOF |
| */ |
| heredoc.data = xzalloc(1); /* start as "", not as NULL */ |
| |
| goto jump_in; |
| |
| while (1) { |
| ch = i_getch(input); |
| if (ch != EOF) |
| nommu_addchr(as_string, ch); |
| if (ch == '\n' || ch == EOF) { |
| check_heredoc_end: |
| if ((heredoc_flags & HEREDOC_QUOTED) || prev != '\\') { |
| /* End-of-line, and not a line continuation */ |
| if (strcmp(heredoc.data + past_EOL, word) == 0) { |
| heredoc.data[past_EOL] = '\0'; |
| debug_printf_heredoc("parsed '%s' heredoc '%s'\n", word, heredoc.data); |
| return heredoc.data; |
| } |
| if (ch == '\n') { |
| /* This is a new line. |
| * Remember position and backslash-escaping status. |
| */ |
| o_addchr(&heredoc, ch); |
| prev = ch; |
| jump_in: |
| past_EOL = heredoc.length; |
| /* Get 1st char of next line, possibly skipping leading tabs */ |
| do { |
| ch = i_getch(input); |
| if (ch != EOF) |
| nommu_addchr(as_string, ch); |
| } while ((heredoc_flags & HEREDOC_SKIPTABS) && ch == '\t'); |
| /* If this immediately ended the line, |
| * go back to end-of-line checks. |
| */ |
| if (ch == '\n') |
| goto check_heredoc_end; |
| } |
| } else { |
| /* Backslash-line continuation in an unquoted |
| * heredoc. This does not need special handling |
| * for heredoc body (unquoted heredocs are |
| * expanded on "execution" and that would take |
| * care of this case too), but not the case |
| * of line continuation *in terminator*: |
| * cat <<EOF |
| * Ok1 |
| * EO\ |
| * F |
| */ |
| heredoc.data[--heredoc.length] = '\0'; |
| prev = 0; /* not '\' */ |
| continue; |
| } |
| } |
| if (ch == EOF) { |
| o_free(&heredoc); |
| return NULL; /* error */ |
| } |
| o_addchr(&heredoc, ch); |
| nommu_addchr(as_string, ch); |
| if (prev == '\\' && ch == '\\') |
| /* Correctly handle foo\\<eol> (not a line cont.) */ |
| prev = 0; /* not '\' */ |
| else |
| prev = ch; |
| } |
| } |
| |
| /* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs |
| * and load them all. There should be exactly heredoc_cnt of them. |
| */ |
| #if BB_MMU |
| #define fetch_heredocs(as_string, pi, heredoc_cnt, input) \ |
| fetch_heredocs(pi, heredoc_cnt, input) |
| #endif |
| static int fetch_heredocs(o_string *as_string, struct pipe *pi, int heredoc_cnt, struct in_str *input) |
| { |
| while (pi && heredoc_cnt) { |
| int i; |
| struct command *cmd = pi->cmds; |
| |
| debug_printf_heredoc("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n", |
| pi->num_cmds, |
| cmd->argv ? cmd->argv[0] : "NONE" |
| ); |
| for (i = 0; i < pi->num_cmds; i++) { |
| struct redir_struct *redir = cmd->redirects; |
| |
| debug_printf_heredoc("fetch_heredocs: %d cmd argv0:'%s'\n", |
| i, cmd->argv ? cmd->argv[0] : "NONE"); |
| while (redir) { |
| if (redir->rd_type == REDIRECT_HEREDOC) { |
| char *p; |
| |
| redir->rd_type = REDIRECT_HEREDOC2; |
| /* redir->rd_dup is (ab)used to indicate <<- */ |
| p = fetch_till_str(as_string, input, |
| redir->rd_filename, redir->rd_dup); |
| if (!p) { |
| syntax_error("unexpected EOF in here document"); |
| return -1; |
| } |
| free(redir->rd_filename); |
| redir->rd_filename = p; |
| heredoc_cnt--; |
| } |
| redir = redir->next; |
| } |
| if (cmd->group) { |
| //bb_error_msg("%s:%u heredoc_cnt:%d", __func__, __LINE__, heredoc_cnt); |
| heredoc_cnt = fetch_heredocs(as_string, cmd->group, heredoc_cnt, input); |
| //bb_error_msg("%s:%u heredoc_cnt:%d", __func__, __LINE__, heredoc_cnt); |
| if (heredoc_cnt < 0) |
| return heredoc_cnt; /* error */ |
| } |
| cmd++; |
| } |
| pi = pi->next; |
| } |
| return heredoc_cnt; |
| } |
| |
| |
| static int run_list(struct pipe *pi); |
| #if BB_MMU |
| #define parse_stream(pstring, heredoc_cnt_ptr, input, end_trigger) \ |
| parse_stream(heredoc_cnt_ptr, input, end_trigger) |
| #endif |
| static struct pipe *parse_stream(char **pstring, |
| int *heredoc_cnt_ptr, |
| struct in_str *input, |
| int end_trigger); |
| |
| /* Returns number of heredocs not yet consumed, |
| * or -1 on error. |
| */ |
| static int parse_group(struct parse_context *ctx, |
| struct in_str *input, int ch) |
| { |
| /* ctx->word contains characters seen prior to ( or {. |
| * Typically it's empty, but for function defs, |
| * it contains function name (without '()'). */ |
| #if BB_MMU |
| # define as_string NULL |
| #else |
| char *as_string = NULL; |
| #endif |
| struct pipe *pipe_list; |
| int heredoc_cnt = 0; |
| int endch; |
| struct command *command = ctx->command; |
| |
| debug_printf_parse("parse_group entered\n"); |
| #if ENABLE_HUSH_FUNCTIONS |
| if (ch == '(' && !ctx->word.has_quoted_part) { |
| if (ctx->word.length) |
| if (done_word(ctx)) |
| return -1; |
| if (!command->argv) |
| goto skip; /* (... */ |
| if (command->argv[1]) { /* word word ... (... */ |
| syntax_error_unexpected_ch('('); |
| return -1; |
| } |
| /* it is "word(..." or "word (..." */ |
| do |
| ch = i_getch(input); |
| while (ch == ' ' || ch == '\t'); |
| if (ch != ')') { |
| syntax_error_unexpected_ch(ch); |
| return -1; |
| } |
| nommu_addchr(&ctx->as_string, ch); |
| do |
| ch = i_getch(input); |
| while (ch == ' ' || ch == '\t' || ch == '\n'); |
| if (ch != '{' && ch != '(') { |
| syntax_error_unexpected_ch(ch); |
| return -1; |
| } |
| nommu_addchr(&ctx->as_string, ch); |
| command->cmd_type = CMD_FUNCDEF; |
| goto skip; |
| } |
| #endif |
| |
| #if 0 /* Prevented by caller */ |
| if (command->argv /* word [word]{... */ |
| || ctx->word.length /* word{... */ |
| || ctx->word.has_quoted_part /* ""{... */ |
| ) { |
| syntax_error(NULL); |
| debug_printf_parse("parse_group return -1: " |
| "syntax error, groups and arglists don't mix\n"); |
| return -1; |
| } |
| #endif |
| |
| IF_HUSH_FUNCTIONS(skip:) |
| |
| endch = '}'; |
| if (ch == '(') { |
| endch = ')'; |
| IF_HUSH_FUNCTIONS(if (command->cmd_type != CMD_FUNCDEF)) |
| command->cmd_type = CMD_SUBSHELL; |
| } else { |
| /* bash does not allow "{echo...", requires whitespace */ |
| ch = i_peek(input); |
| if (ch != ' ' && ch != '\t' && ch != '\n' |
| && ch != '(' /* but "{(..." is allowed (without whitespace) */ |
| ) { |
| syntax_error_unexpected_ch(ch); |
| return -1; |
| } |
| if (ch != '(') { |
| ch = i_getch(input); |
| nommu_addchr(&ctx->as_string, ch); |
| } |
| } |
| |
| debug_printf_heredoc("calling parse_stream, heredoc_cnt:%d\n", heredoc_cnt); |
| pipe_list = parse_stream(&as_string, &heredoc_cnt, input, endch); |
| debug_printf_heredoc("parse_stream returned: heredoc_cnt:%d\n", heredoc_cnt); |
| #if !BB_MMU |
| if (as_string) |
| o_addstr(&ctx->as_string, as_string); |
| #endif |
| |
| /* empty ()/{} or parse error? */ |
| if (!pipe_list || pipe_list == ERR_PTR) { |
| /* parse_stream already emitted error msg */ |
| if (!BB_MMU) |
| free(as_string); |
| debug_printf_parse("parse_group return -1: " |
| "parse_stream returned %p\n", pipe_list); |
| return -1; |
| } |
| #if !BB_MMU |
| as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */ |
| command->group_as_string = as_string; |
| debug_printf_parse("end of group, remembering as:'%s'\n", |
| command->group_as_string); |
| #endif |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| /* Convert "f() (cmds)" to "f() {(cmds)}" */ |
| if (command->cmd_type == CMD_FUNCDEF && endch == ')') { |
| struct command *cmd2; |
| |
| cmd2 = xzalloc(sizeof(*cmd2)); |
| cmd2->cmd_type = CMD_SUBSHELL; |
| cmd2->group = pipe_list; |
| # if !BB_MMU |
| //UNTESTED! |
| cmd2->group_as_string = command->group_as_string; |
| command->group_as_string = xasprintf("(%s)", command->group_as_string); |
| # endif |
| |
| pipe_list = new_pipe(); |
| pipe_list->cmds = cmd2; |
| pipe_list->num_cmds = 1; |
| } |
| #endif |
| |
| command->group = pipe_list; |
| |
| debug_printf_parse("parse_group return %d\n", heredoc_cnt); |
| return heredoc_cnt; |
| /* command remains "open", available for possible redirects */ |
| #undef as_string |
| } |
| |
| #if ENABLE_HUSH_TICK || ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_DOLLAR_OPS |
| /* Subroutines for copying $(...) and `...` things */ |
| /* '...' */ |
| static int add_till_single_quote(o_string *dest, struct in_str *input) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| return 0; |
| } |
| if (ch == '\'') |
| return 1; |
| o_addchr(dest, ch); |
| } |
| } |
| static int add_till_single_quote_dquoted(o_string *dest, struct in_str *input) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| return 0; |
| } |
| if (ch == '\'') |
| return 1; |
| o_addqchr(dest, ch); |
| } |
| } |
| /* "...\"...`..`...." - do we need to handle "...$(..)..." too? */ |
| static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote); |
| static int add_till_double_quote(o_string *dest, struct in_str *input) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('"'); |
| return 0; |
| } |
| if (ch == '"') |
| return 1; |
| if (ch == '\\') { /* \x. Copy both chars. */ |
| o_addchr(dest, ch); |
| ch = i_getch(input); |
| } |
| o_addchr(dest, ch); |
| if (ch == '`') { |
| if (!add_till_backquote(dest, input, /*in_dquote:*/ 1)) |
| return 0; |
| o_addchr(dest, ch); |
| continue; |
| } |
| //if (ch == '$') ... |
| } |
| } |
| /* Process `cmd` - copy contents until "`" is seen. Complicated by |
| * \` quoting. |
| * "Within the backquoted style of command substitution, backslash |
| * shall retain its literal meaning, except when followed by: '$', '`', or '\'. |
| * The search for the matching backquote shall be satisfied by the first |
| * backquote found without a preceding backslash; during this search, |
| * if a non-escaped backquote is encountered within a shell comment, |
| * a here-document, an embedded command substitution of the $(command) |
| * form, or a quoted string, undefined results occur. A single-quoted |
| * or double-quoted string that begins, but does not end, within the |
| * "`...`" sequence produces undefined results." |
| * Example Output |
| * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST |
| */ |
| static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == '`') |
| return 1; |
| if (ch == '\\') { |
| /* \x. Copy both unless it is \`, \$, \\ and maybe \" */ |
| ch = i_getch(input); |
| if (ch != '`' |
| && ch != '$' |
| && ch != '\\' |
| && (!in_dquote || ch != '"') |
| ) { |
| o_addchr(dest, '\\'); |
| } |
| } |
| if (ch == EOF) { |
| syntax_error_unterm_ch('`'); |
| return 0; |
| } |
| o_addchr(dest, ch); |
| } |
| } |
| /* Process $(cmd) - copy contents until ")" is seen. Complicated by |
| * quoting and nested ()s. |
| * "With the $(command) style of command substitution, all characters |
| * following the open parenthesis to the matching closing parenthesis |
| * constitute the command. Any valid shell script can be used for command, |
| * except a script consisting solely of redirections which produces |
| * unspecified results." |
| * Example Output |
| * echo $(echo '(TEST)' BEST) (TEST) BEST |
| * echo $(echo 'TEST)' BEST) TEST) BEST |
| * echo $(echo \(\(TEST\) BEST) ((TEST) BEST |
| * |
| * Also adapted to eat ${var%...} and $((...)) constructs, since ... part |
| * can contain arbitrary constructs, just like $(cmd). |
| * In bash compat mode, it needs to also be able to stop on ':' or '/' |
| * for ${var:N[:M]} and ${var/P[/R]} parsing. |
| */ |
| #define DOUBLE_CLOSE_CHAR_FLAG 0x80 |
| static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch) |
| { |
| int ch; |
| char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG; |
| # if BASH_SUBSTR || BASH_PATTERN_SUBST |
| char end_char2 = end_ch >> 8; |
| # endif |
| end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1); |
| |
| # if ENABLE_HUSH_INTERACTIVE |
| G.promptmode = 1; /* PS2 */ |
| # endif |
| debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode); |
| |
| while (1) { |
| ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch(end_ch); |
| return 0; |
| } |
| if (ch == end_ch |
| # if BASH_SUBSTR || BASH_PATTERN_SUBST |
| || ch == end_char2 |
| # endif |
| ) { |
| if (!dbl) |
| break; |
| /* we look for closing )) of $((EXPR)) */ |
| if (i_peek_and_eat_bkslash_nl(input) == end_ch) { |
| i_getch(input); /* eat second ')' */ |
| break; |
| } |
| } |
| o_addchr(dest, ch); |
| //bb_error_msg("%s:o_addchr('%c')", __func__, ch); |
| if (ch == '(' || ch == '{') { |
| ch = (ch == '(' ? ')' : '}'); |
| if (!add_till_closing_bracket(dest, input, ch)) |
| return 0; |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '\'') { |
| if (!add_till_single_quote(dest, input)) |
| return 0; |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '"') { |
| if (!add_till_double_quote(dest, input)) |
| return 0; |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '`') { |
| if (!add_till_backquote(dest, input, /*in_dquote:*/ 0)) |
| return 0; |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '\\') { |
| /* \x. Copy verbatim. Important for \(, \) */ |
| ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch(end_ch); |
| return 0; |
| } |
| # if 0 |
| if (ch == '\n') { |
| /* "backslash+newline", ignore both */ |
| o_delchr(dest); /* undo insertion of '\' */ |
| continue; |
| } |
| # endif |
| o_addchr(dest, ch); |
| //bb_error_msg("%s:o_addchr('%c') after '\\'", __func__, ch); |
| continue; |
| } |
| } |
| debug_printf_parse("%s return '%s' ch:'%c'\n", __func__, dest->data, ch); |
| return ch; |
| } |
| #endif /* ENABLE_HUSH_TICK || ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_DOLLAR_OPS */ |
| |
| #if BASH_DOLLAR_SQUOTE |
| /* Return code: 1 for "found and parsed", 0 for "seen something else" */ |
| # if BB_MMU |
| #define parse_dollar_squote(as_string, dest, input) \ |
| parse_dollar_squote(dest, input) |
| #define as_string NULL |
| # endif |
| static int parse_dollar_squote(o_string *as_string, o_string *dest, struct in_str *input) |
| { |
| int start; |
| int ch = i_peek_and_eat_bkslash_nl(input); /* first character after the $ */ |
| debug_printf_parse("parse_dollar_squote entered: ch='%c'\n", ch); |
| if (ch != '\'') |
| return 0; |
| |
| dest->has_quoted_part = 1; |
| start = dest->length; |
| |
| ch = i_getch(input); /* eat ' */ |
| nommu_addchr(as_string, ch); |
| while (1) { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| return 0; |
| } |
| if (ch == '\'') |
| break; |
| if (ch == SPECIAL_VAR_SYMBOL) { |
| /* Convert raw ^C to corresponding special variable reference */ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, SPECIAL_VAR_QUOTED_SVS); |
| /* will addchr() another SPECIAL_VAR_SYMBOL (see after the if() block) */ |
| } else if (ch == '\\') { |
| static const char C_escapes[] ALIGN1 = "nrbtfav""x\\01234567"; |
| |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| if (strchr(C_escapes, ch)) { |
| char buf[4]; |
| char *p = buf; |
| int cnt = 2; |
| |
| buf[0] = ch; |
| if ((unsigned char)(ch - '0') <= 7) { /* \ooo */ |
| do { |
| ch = i_peek(input); |
| if ((unsigned char)(ch - '0') > 7) |
| break; |
| *++p = ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| } while (--cnt != 0); |
| } else if (ch == 'x') { /* \xHH */ |
| do { |
| ch = i_peek(input); |
| if (!isxdigit(ch)) |
| break; |
| *++p = ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| } while (--cnt != 0); |
| if (cnt == 2) { /* \x but next char is "bad" */ |
| ch = 'x'; |
| goto unrecognized; |
| } |
| } /* else simple seq like \\ or \t */ |
| *++p = '\0'; |
| p = buf; |
| ch = bb_process_escape_sequence((void*)&p); |
| //bb_error_msg("buf:'%s' ch:%x", buf, ch); |
| if (ch == '\0') |
| continue; /* bash compat: $'...\0...' emits nothing */ |
| } else { /* unrecognized "\z": encode both chars unless ' or " */ |
| if (ch != '\'' && ch != '"') { |
| unrecognized: |
| o_addqchr(dest, '\\'); |
| } |
| } |
| } /* if (\...) */ |
| o_addqchr(dest, ch); |
| } |
| |
| if (dest->length == start) { |
| /* $'', $'\0', $'\000\x00' and the like */ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } |
| |
| return 1; |
| # undef as_string |
| } |
| #else |
| # define parse_dollar_squote(as_string, dest, input) 0 |
| #endif /* BASH_DOLLAR_SQUOTE */ |
| |
| /* Return code: 0 for OK, 1 for syntax error */ |
| #if BB_MMU |
| #define parse_dollar(as_string, dest, input, quote_mask) \ |
| parse_dollar(dest, input, quote_mask) |
| #define as_string NULL |
| #endif |
| static int parse_dollar(o_string *as_string, |
| o_string *dest, |
| struct in_str *input, unsigned char quote_mask) |
| { |
| int ch = i_peek_and_eat_bkslash_nl(input); /* first character after the $ */ |
| |
| debug_printf_parse("parse_dollar entered: ch='%c' quote_mask:0x%x\n", ch, quote_mask); |
| if (isalpha(ch)) { |
| make_var: |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| /*make_var1:*/ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| while (1) { |
| debug_printf_parse(": '%c'\n", ch); |
| o_addchr(dest, ch | quote_mask); |
| quote_mask = 0; |
| ch = i_peek_and_eat_bkslash_nl(input); |
| if (!isalnum(ch) && ch != '_') { |
| /* End of variable name reached */ |
| break; |
| } |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| } |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } else if (isdigit(ch)) { |
| make_one_char_var: |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| debug_printf_parse(": '%c'\n", ch); |
| o_addchr(dest, ch | quote_mask); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } else switch (ch) { |
| case '$': /* pid */ |
| case '!': /* last bg pid */ |
| case '?': /* last exit code */ |
| case '#': /* number of args */ |
| case '*': /* args */ |
| case '@': /* args */ |
| case '-': /* $- option flags set by set builtin or shell options (-i etc) */ |
| goto make_one_char_var; |
| case '{': { |
| char len_single_ch; |
| |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| |
| ch = i_getch(input); /* eat '{' */ |
| nommu_addchr(as_string, ch); |
| |
| ch = i_getch_and_eat_bkslash_nl(input); /* first char after '{' */ |
| /* It should be ${?}, or ${#var}, |
| * or even ${?+subst} - operator acting on a special variable, |
| * or the beginning of variable name. |
| */ |
| if (ch == EOF |
| || (!strchr(_SPECIAL_VARS_STR, ch) && !isalnum(ch)) /* not one of those */ |
| ) { |
| bad_dollar_syntax: |
| syntax_error_unterm_str("${name}"); |
| debug_printf_parse("parse_dollar return 0: unterminated ${name}\n"); |
| return 0; |
| } |
| nommu_addchr(as_string, ch); |
| len_single_ch = ch; |
| ch |= quote_mask; |
| |
| /* It's possible to just call add_till_closing_bracket() at this point. |
| * However, this regresses some of our testsuite cases |
| * which check invalid constructs like ${%}. |
| * Oh well... let's check that the var name part is fine... */ |
| |
| if (isdigit(len_single_ch) |
| || (len_single_ch == '#' && isdigit(i_peek_and_eat_bkslash_nl(input))) |
| ) { |
| /* Execution engine uses plain xatoi_positive() |
| * to interpret ${NNN} and {#NNN}, |
| * check syntax here in the parser. |
| * (bash does not support expressions in ${#NN}, |
| * e.g. ${#$var} and {#1:+WORD} are not supported). |
| */ |
| unsigned cnt = 9; /* max 9 digits for ${NN} and 8 for {#NN} */ |
| while (1) { |
| o_addchr(dest, ch); |
| debug_printf_parse(": '%c'\n", ch); |
| ch = i_getch_and_eat_bkslash_nl(input); |
| nommu_addchr(as_string, ch); |
| if (ch == '}') |
| break; |
| if (--cnt == 0) |
| goto bad_dollar_syntax; |
| if (len_single_ch != '#' && strchr(VAR_SUBST_OPS, ch)) |
| /* ${NN<op>...} is valid */ |
| goto eat_until_closing; |
| if (!isdigit(ch)) |
| goto bad_dollar_syntax; |
| } |
| } else |
| while (1) { |
| unsigned pos; |
| |
| o_addchr(dest, ch); |
| debug_printf_parse(": '%c'\n", ch); |
| |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| if (ch == '}') |
| break; |
| if (!isalnum(ch) && ch != '_') { |
| unsigned end_ch; |
| unsigned char last_ch; |
| /* handle parameter expansions |
| * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02 |
| */ |
| if (!strchr(VAR_SUBST_OPS, ch)) { /* ${var<bad_char>... */ |
| if (len_single_ch != '#' |
| /*|| !strchr(SPECIAL_VARS_STR, ch) - disallow errors like ${#+} ? */ |
| || i_peek(input) != '}' |
| ) { |
| goto bad_dollar_syntax; |
| } |
| /* else: it's "length of C" ${#C} op, |
| * where C is a single char |
| * special var name, e.g. ${#!}. |
| */ |
| } |
| eat_until_closing: |
| /* Eat everything until closing '}' (or ':') */ |
| end_ch = '}'; |
| if (BASH_SUBSTR |
| && ch == ':' |
| && !strchr(MINUS_PLUS_EQUAL_QUESTION, i_peek(input)) |
| ) { |
| /* It's ${var:N[:M]} thing */ |
| end_ch = '}' * 0x100 + ':'; |
| } |
| if (BASH_PATTERN_SUBST |
| && ch == '/' |
| ) { |
| /* It's ${var/[/]pattern[/repl]} thing */ |
| if (i_peek(input) == '/') { /* ${var//pattern[/repl]}? */ |
| i_getch(input); |
| nommu_addchr(as_string, '/'); |
| ch = '\\'; |
| } |
| end_ch = '}' * 0x100 + '/'; |
| } |
| o_addchr(dest, ch); |
| /* The pattern can't be empty. |
| * IOW: if the first char after "${v//" is a slash, |
| * it does not terminate the pattern - it's the first char of the pattern: |
| * v=/dev/ram; echo ${v////-} prints -dev-ram (pattern is "/") |
| * v=/dev/ram; echo ${v///r/-} prints /dev-am (pattern is "/r") |
| */ |
| if (i_peek(input) == '/') { |
| o_addchr(dest, i_getch(input)); |
| } |
| again: |
| if (!BB_MMU) |
| pos = dest->length; |
| #if ENABLE_HUSH_DOLLAR_OPS |
| last_ch = add_till_closing_bracket(dest, input, end_ch); |
| if (last_ch == 0) /* error? */ |
| return 0; |
| #else |
| # error Simple code to only allow ${var} is not implemented |
| #endif |
| if (as_string) { |
| o_addstr(as_string, dest->data + pos); |
| o_addchr(as_string, last_ch); |
| } |
| |
| if ((BASH_SUBSTR || BASH_PATTERN_SUBST) |
| && (end_ch & 0xff00) |
| ) { |
| /* close the first block: */ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| /* while parsing N from ${var:N[:M]} |
| * or pattern from ${var/[/]pattern[/repl]} */ |
| if ((end_ch & 0xff) == last_ch) { |
| /* got ':' or '/'- parse the rest */ |
| end_ch = '}'; |
| goto again; |
| } |
| /* got '}' */ |
| if (BASH_SUBSTR && end_ch == '}' * 0x100 + ':') { |
| /* it's ${var:N} - emulate :999999999 */ |
| o_addstr(dest, "999999999"); |
| } /* else: it's ${var/[/]pattern} */ |
| } |
| break; |
| } |
| len_single_ch = 0; /* it can't be ${#C} op */ |
| } |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| break; |
| } |
| #if ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_TICK |
| case '(': { |
| unsigned pos; |
| |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| # if ENABLE_FEATURE_SH_MATH |
| if (i_peek_and_eat_bkslash_nl(input) == '(') { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, quote_mask | '+'); |
| if (!BB_MMU) |
| pos = dest->length; |
| if (!add_till_closing_bracket(dest, input, ')' | DOUBLE_CLOSE_CHAR_FLAG)) |
| return 0; /* error */ |
| if (as_string) { |
| o_addstr(as_string, dest->data + pos); |
| o_addchr(as_string, ')'); |
| o_addchr(as_string, ')'); |
| } |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| break; |
| } |
| # endif |
| # if ENABLE_HUSH_TICK |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, quote_mask | '`'); |
| if (!BB_MMU) |
| pos = dest->length; |
| if (!add_till_closing_bracket(dest, input, ')')) |
| return 0; /* error */ |
| if (as_string) { |
| o_addstr(as_string, dest->data + pos); |
| o_addchr(as_string, ')'); |
| } |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| # endif |
| break; |
| } |
| #endif |
| case '_': |
| goto make_var; |
| #if 0 |
| /* TODO: $_: */ |
| /* $_ Shell or shell script name; or last argument of last command |
| * (if last command wasn't a pipe; if it was, bash sets $_ to ""); |
| * but in command's env, set to full pathname used to invoke it */ |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| ch = i_peek_and_eat_bkslash_nl(input); |
| if (isalnum(ch)) { /* it's $_name or $_123 */ |
| ch = '_'; |
| goto make_var1; |
| } |
| /* else: it's $_ */ |
| #endif |
| default: |
| o_addQchr(dest, '$'); |
| } |
| debug_printf_parse("parse_dollar return 1 (ok)\n"); |
| return 1; |
| #undef as_string |
| } |
| |
| #if BB_MMU |
| #define encode_string(as_string, dest, input, dquote_end) \ |
| encode_string(dest, input, dquote_end) |
| #define as_string NULL |
| #endif |
| static int encode_string(o_string *as_string, |
| o_string *dest, |
| struct in_str *input, |
| int dquote_end) |
| { |
| int ch; |
| int next; |
| |
| again: |
| ch = i_getch(input); |
| if (ch != EOF) |
| nommu_addchr(as_string, ch); |
| if (ch == dquote_end) { /* may be only '"' or EOF */ |
| debug_printf_parse("encode_string return 1 (ok)\n"); |
| return 1; |
| } |
| /* note: can't move it above ch == dquote_end check! */ |
| if (ch == EOF) { |
| syntax_error_unterm_ch('"'); |
| return 0; /* error */ |
| } |
| next = '\0'; |
| if (ch != '\n') { |
| next = i_peek(input); |
| } |
| debug_printf_parse("\" ch=%c (%d) escape=%d\n", |
| ch, ch, !!(dest->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)); |
| if (ch == '\\') { |
| if (next == EOF) { |
| /* Testcase: in interactive shell a file with |
| * echo "unterminated string\<eof> |
| * is sourced. |
| */ |
| syntax_error_unterm_ch('"'); |
| return 0; /* error */ |
| } |
| /* bash: |
| * "The backslash retains its special meaning [in "..."] |
| * only when followed by one of the following characters: |
| * $, `, ", \, or <newline>. A double quote may be quoted |
| * within double quotes by preceding it with a backslash." |
| * NB: in (unquoted) heredoc, above does not apply to ", |
| * therefore we check for it by "next == dquote_end" cond. |
| */ |
| if (next == dquote_end || strchr("$`\\\n", next)) { |
| ch = i_getch(input); /* eat next */ |
| if (ch == '\n') |
| goto again; /* skip \<newline> */ |
| } /* else: ch remains == '\\', and we double it below: */ |
| o_addqchr(dest, ch); /* \c if c is a glob char, else just c */ |
| nommu_addchr(as_string, ch); |
| goto again; |
| } |
| if (ch == '$') { |
| //if (parse_dollar_squote(as_string, dest, input)) |
| // goto again; |
| if (!parse_dollar(as_string, dest, input, /*quote_mask:*/ 0x80)) { |
| debug_printf_parse("encode_string return 0: " |
| "parse_dollar returned 0 (error)\n"); |
| return 0; |
| } |
| goto again; |
| } |
| #if ENABLE_HUSH_TICK |
| if (ch == '`') { |
| //unsigned pos = dest->length; |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, 0x80 | '`'); |
| if (!add_till_backquote(dest, input, /*in_dquote:*/ dquote_end == '"')) |
| return 0; /* error */ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos); |
| goto again; |
| } |
| #endif |
| o_addQchr(dest, ch); |
| if (ch == SPECIAL_VAR_SYMBOL) { |
| /* Convert "^C" to corresponding special variable reference */ |
| o_addchr(dest, SPECIAL_VAR_QUOTED_SVS); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } |
| goto again; |
| #undef as_string |
| } |
| |
| /* |
| * Scan input until EOF or end_trigger char. |
| * Return a list of pipes to execute, or NULL on EOF |
| * or if end_trigger character is met. |
| * On syntax error, exit if shell is not interactive, |
| * reset parsing machinery and start parsing anew, |
| * or return ERR_PTR. |
| */ |
| static struct pipe *parse_stream(char **pstring, |
| int *heredoc_cnt_ptr, |
| struct in_str *input, |
| int end_trigger) |
| { |
| struct parse_context ctx; |
| int heredoc_cnt; |
| |
| /* Single-quote triggers a bypass of the main loop until its mate is |
| * found. When recursing, quote state is passed in via ctx.word.o_expflags. |
| */ |
| debug_printf_parse("parse_stream entered, end_trigger='%c'\n", |
| end_trigger ? end_trigger : 'X'); |
| debug_enter(); |
| |
| initialize_context(&ctx); |
| |
| /* If very first arg is "" or '', ctx.word.data may end up NULL. |
| * Preventing this: |
| */ |
| ctx.word.data = xzalloc(1); /* start as "", not as NULL */ |
| |
| /* We used to separate words on $IFS here. This was wrong. |
| * $IFS is used only for word splitting when $var is expanded, |
| * here we should use blank chars as separators, not $IFS |
| */ |
| |
| heredoc_cnt = 0; |
| while (1) { |
| const char *is_blank; |
| const char *is_special; |
| int ch; |
| int next; |
| int redir_fd; |
| redir_type redir_style; |
| |
| ch = i_getch(input); |
| debug_printf_parse(": ch=%c (%d) escape=%d\n", |
| ch, ch, !!(ctx.word.o_expflags & EXP_FLAG_ESC_GLOB_CHARS)); |
| if (ch == EOF) { |
| struct pipe *pi; |
| |
| if (heredoc_cnt) { |
| syntax_error_unterm_str("here document"); |
| goto parse_error_exitcode1; |
| } |
| if (end_trigger == ')') { |
| syntax_error_unterm_ch('('); |
| goto parse_error_exitcode1; |
| } |
| if (end_trigger == '}') { |
| syntax_error_unterm_ch('{'); |
| goto parse_error_exitcode1; |
| } |
| |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| o_free_and_set_NULL(&ctx.word); |
| done_pipe(&ctx, PIPE_SEQ); |
| pi = ctx.list_head; |
| /* If we got nothing... */ |
| /* (this makes bare "&" cmd a no-op. |
| * bash says: "syntax error near unexpected token '&'") */ |
| if (pi->num_cmds == 0 |
| IF_HAS_KEYWORDS(&& pi->res_word == RES_NONE) |
| ) { |
| free_pipe_list(pi); |
| pi = NULL; |
| } |
| #if !BB_MMU |
| debug_printf_parse("as_string1 '%s'\n", ctx.as_string.data); |
| if (pstring) |
| *pstring = ctx.as_string.data; |
| else |
| o_free(&ctx.as_string); |
| #endif |
| // heredoc_cnt must be 0 here anyway |
| //if (heredoc_cnt_ptr) |
| // *heredoc_cnt_ptr = heredoc_cnt; |
| debug_leave(); |
| debug_printf_heredoc("parse_stream return heredoc_cnt:%d\n", heredoc_cnt); |
| debug_printf_parse("parse_stream return %p\n", pi); |
| return pi; |
| } |
| |
| /* Handle "'" and "\" first, as they won't play nice with |
| * i_peek_and_eat_bkslash_nl() anyway: |
| * echo z\\ |
| * and |
| * echo '\ |
| * ' |
| * would break. |
| */ |
| if (ch == '\\') { |
| ch = i_getch(input); |
| if (ch == '\n') |
| continue; /* drop \<newline>, get next char */ |
| nommu_addchr(&ctx.as_string, '\\'); |
| if (ch == SPECIAL_VAR_SYMBOL) { |
| nommu_addchr(&ctx.as_string, ch); |
| /* Convert \^C to corresponding special variable reference */ |
| goto case_SPECIAL_VAR_SYMBOL; |
| } |
| o_addchr(&ctx.word, '\\'); |
| if (ch == EOF) { |
| /* Testcase: eval 'echo Ok\' */ |
| /* bash-4.3.43 was removing backslash, |
| * but 4.4.19 retains it, most other shells too |
| */ |
| continue; /* get next char */ |
| } |
| /* Example: echo Hello \2>file |
| * we need to know that word 2 is quoted |
| */ |
| ctx.word.has_quoted_part = 1; |
| nommu_addchr(&ctx.as_string, ch); |
| o_addchr(&ctx.word, ch); |
| continue; /* get next char */ |
| } |
| nommu_addchr(&ctx.as_string, ch); |
| if (ch == '\'') { |
| ctx.word.has_quoted_part = 1; |
| next = i_getch(input); |
| if (next == '\'' && !ctx.pending_redirect) |
| goto insert_empty_quoted_str_marker; |
| |
| ch = next; |
| while (1) { |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| goto parse_error_exitcode1; |
| } |
| nommu_addchr(&ctx.as_string, ch); |
| if (ch == '\'') |
| break; |
| if (ch == SPECIAL_VAR_SYMBOL) { |
| /* Convert raw ^C to corresponding special variable reference */ |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| o_addchr(&ctx.word, SPECIAL_VAR_QUOTED_SVS); |
| } |
| o_addqchr(&ctx.word, ch); |
| ch = i_getch(input); |
| } |
| continue; /* get next char */ |
| } |
| |
| next = '\0'; |
| if (ch != '\n') |
| next = i_peek_and_eat_bkslash_nl(input); |
| |
| is_special = "{}<>&|();#" /* special outside of "str" */ |
| "$\"" IF_HUSH_TICK("`") /* always special */ |
| SPECIAL_VAR_SYMBOL_STR; |
| #if defined(CMD_TEST2_SINGLEWORD_NOGLOB) |
| if (ctx.command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB) { |
| /* In [[ ]], {}<>&|() are not special */ |
| is_special += 8; |
| } else |
| #endif |
| /* Are { and } special here? */ |
| if (ctx.command->argv /* word [word]{... - non-special */ |
| || ctx.word.length /* word{... - non-special */ |
| || ctx.word.has_quoted_part /* ""{... - non-special */ |
| || (next != ';' /* }; - special */ |
| && next != ')' /* }) - special */ |
| && next != '(' /* {( - special */ |
| && next != '&' /* }& and }&& ... - special */ |
| && next != '|' /* }|| ... - special */ |
| && !strchr(defifs, next) /* {word - non-special */ |
| ) |
| ) { |
| /* They are not special, skip "{}" */ |
| is_special += 2; |
| } |
| is_special = strchr(is_special, ch); |
| is_blank = strchr(defifs, ch); |
| |
| if (!is_special && !is_blank) { /* ordinary char */ |
| ordinary_char: |
| o_addQchr(&ctx.word, ch); |
| if ((ctx.is_assignment == MAYBE_ASSIGNMENT |
| || ctx.is_assignment == WORD_IS_KEYWORD) |
| && ch == '=' |
| && endofname(ctx.word.data)[0] == '=' |
| ) { |
| ctx.is_assignment = DEFINITELY_ASSIGNMENT; |
| debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]); |
| } |
| continue; |
| } |
| |
| if (is_blank) { |
| #if ENABLE_HUSH_LINENO_VAR |
| /* Case: |
| * "while ...; do<whitespace><newline> |
| * cmd ..." |
| * would think that "cmd" starts in <whitespace> - |
| * i.e., at the previous line. |
| * We need to skip all whitespace before newlines. |
| */ |
| while (ch != '\n') { |
| next = i_peek(input); |
| if (next != ' ' && next != '\t' && next != '\n') |
| break; /* next char is not ws */ |
| ch = i_getch(input); |
| } |
| /* ch == last eaten whitespace char */ |
| #endif |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| if (ch == '\n') { |
| /* Is this a case when newline is simply ignored? |
| * Some examples: |
| * "cmd | <newline> cmd ..." |
| * "case ... in <newline> word) ..." |
| */ |
| if (IS_NULL_CMD(ctx.command) |
| && ctx.word.length == 0 |
| && !ctx.word.has_quoted_part |
| && heredoc_cnt == 0 |
| ) { |
| /* This newline can be ignored. But... |
| * Without check #1, interactive shell |
| * ignores even bare <newline>, |
| * and shows the continuation prompt: |
| * ps1_prompt$ <enter> |
| * ps2> _ <=== wrong, should be ps1 |
| * Without check #2, "cmd & <newline>" |
| * is similarly mistreated. |
| * (BTW, this makes "cmd & cmd" |
| * and "cmd && cmd" non-orthogonal. |
| * Really, ask yourself, why |
| * "cmd && <newline>" doesn't start |
| * cmd but waits for more input? |
| * The only reason is that it might be |
| * a "cmd1 && <nl> cmd2 &" construct, |
| * cmd1 may need to run in BG). |
| */ |
| struct pipe *pi = ctx.list_head; |
| if (pi->num_cmds != 0 /* check #1 */ |
| && pi->followup != PIPE_BG /* check #2 */ |
| ) { |
| continue; |
| } |
| } |
| /* Treat newline as a command separator. */ |
| done_pipe(&ctx, PIPE_SEQ); |
| debug_printf_heredoc("heredoc_cnt:%d\n", heredoc_cnt); |
| if (heredoc_cnt) { |
| heredoc_cnt = fetch_heredocs(&ctx.as_string, ctx.list_head, heredoc_cnt, input); |
| if (heredoc_cnt != 0) |
| goto parse_error_exitcode1; |
| } |
| ctx.is_assignment = MAYBE_ASSIGNMENT; |
| debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]); |
| ch = ';'; |
| /* note: if (is_blank) continue; |
| * will still trigger for us */ |
| } |
| } |
| |
| /* "cmd}" or "cmd }..." without semicolon or &: |
| * } is an ordinary char in this case, even inside { cmd; } |
| * Pathological example: { ""}; } should exec "}" cmd |
| */ |
| if (ch == '}') { |
| if (ctx.word.length != 0 /* word} */ |
| || ctx.word.has_quoted_part /* ""} */ |
| ) { |
| goto ordinary_char; |
| } |
| if (!IS_NULL_CMD(ctx.command)) { /* cmd } */ |
| /* Generally, there should be semicolon: "cmd; }" |
| * However, bash allows to omit it if "cmd" is |
| * a group. Examples: |
| * { { echo 1; } } |
| * {(echo 1)} |
| * { echo 0 >&2 | { echo 1; } } |
| * { while false; do :; done } |
| * { case a in b) ;; esac } |
| */ |
| if (ctx.command->group) |
| goto term_group; |
| goto ordinary_char; |
| } |
| if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */ |
| /* Can't be an end of {cmd}, skip the check */ |
| goto skip_end_trigger; |
| /* else: } does terminate a group */ |
| } |
| term_group: |
| if (end_trigger && end_trigger == ch |
| && (ch != ';' || heredoc_cnt == 0) |
| #if ENABLE_HUSH_CASE |
| && (ch != ')' |
| || ctx.ctx_res_w != RES_MATCH |
| || (!ctx.word.has_quoted_part && strcmp(ctx.word.data, "esac") == 0) |
| ) |
| #endif |
| ) { |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| done_pipe(&ctx, PIPE_SEQ); |
| ctx.is_assignment = MAYBE_ASSIGNMENT; |
| debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]); |
| /* Do we sit outside of any if's, loops or case's? */ |
| if (!HAS_KEYWORDS |
| IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0)) |
| ) { |
| o_free_and_set_NULL(&ctx.word); |
| #if !BB_MMU |
| debug_printf_parse("as_string2 '%s'\n", ctx.as_string.data); |
| if (pstring) |
| *pstring = ctx.as_string.data; |
| else |
| o_free(&ctx.as_string); |
| #endif |
| if (ch != ';' && IS_NULL_PIPE(ctx.list_head)) { |
| /* Example: bare "{ }", "()" */ |
| G.last_exitcode = 2; /* bash compat */ |
| syntax_error_unexpected_ch(ch); |
| goto parse_error; |
| } |
| if (heredoc_cnt_ptr) |
| *heredoc_cnt_ptr = heredoc_cnt; |
| debug_printf_heredoc("parse_stream return heredoc_cnt:%d\n", heredoc_cnt); |
| debug_printf_parse("parse_stream return %p: " |
| "end_trigger char found\n", |
| ctx.list_head); |
| debug_leave(); |
| return ctx.list_head; |
| } |
| } |
| |
| if (is_blank) |
| continue; |
| |
| /* Catch <, > before deciding whether this word is |
| * an assignment. a=1 2>z b=2: b=2 is still assignment */ |
| switch (ch) { |
| case '>': |
| redir_fd = redirect_opt_num(&ctx.word); |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| redir_style = REDIRECT_OVERWRITE; |
| if (next == '>') { |
| redir_style = REDIRECT_APPEND; |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| } |
| #if 0 |
| else if (next == '(') { |
| syntax_error(">(process) not supported"); |
| goto parse_error_exitcode1; |
| } |
| #endif |
| if (parse_redirect(&ctx, redir_fd, redir_style, input)) |
| goto parse_error_exitcode1; |
| continue; /* get next char */ |
| case '<': |
| redir_fd = redirect_opt_num(&ctx.word); |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| redir_style = REDIRECT_INPUT; |
| if (next == '<') { |
| redir_style = REDIRECT_HEREDOC; |
| heredoc_cnt++; |
| debug_printf_heredoc("++heredoc_cnt=%d\n", heredoc_cnt); |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| } else if (next == '>') { |
| redir_style = REDIRECT_IO; |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| } |
| #if 0 |
| else if (next == '(') { |
| syntax_error("<(process) not supported"); |
| goto parse_error_exitcode1; |
| } |
| #endif |
| if (parse_redirect(&ctx, redir_fd, redir_style, input)) |
| goto parse_error_exitcode1; |
| continue; /* get next char */ |
| case '#': |
| if (ctx.word.length == 0 && !ctx.word.has_quoted_part) { |
| /* skip "#comment" */ |
| /* note: we do not add it to &ctx.as_string */ |
| /* TODO: in bash: |
| * comment inside $() goes to the next \n, even inside quoted string (!): |
| * cmd "$(cmd2 #comment)" - syntax error |
| * cmd "`cmd2 #comment`" - ok |
| * We accept both (comment ends where command subst ends, in both cases). |
| */ |
| while (1) { |
| ch = i_peek(input); |
| if (ch == '\n') { |
| nommu_addchr(&ctx.as_string, '\n'); |
| break; |
| } |
| ch = i_getch(input); |
| if (ch == EOF) |
| break; |
| } |
| continue; /* get next char */ |
| } |
| break; |
| } |
| skip_end_trigger: |
| |
| if (ctx.is_assignment == MAYBE_ASSIGNMENT |
| /* check that we are not in word in "a=1 2>word b=1": */ |
| && !ctx.pending_redirect |
| ) { |
| /* ch is a special char and thus this word |
| * cannot be an assignment */ |
| ctx.is_assignment = NOT_ASSIGNMENT; |
| debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]); |
| } |
| |
| /* Note: nommu_addchr(&ctx.as_string, ch) is already done */ |
| |
| switch (ch) { |
| case_SPECIAL_VAR_SYMBOL: |
| case SPECIAL_VAR_SYMBOL: |
| /* Convert raw ^C to corresponding special variable reference */ |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| o_addchr(&ctx.word, SPECIAL_VAR_QUOTED_SVS); |
| /* fall through */ |
| case '#': |
| /* non-comment #: "echo a#b" etc */ |
| o_addchr(&ctx.word, ch); |
| continue; /* get next char */ |
| case '$': |
| if (parse_dollar_squote(&ctx.as_string, &ctx.word, input)) |
| continue; /* get next char */ |
| if (!parse_dollar(&ctx.as_string, &ctx.word, input, /*quote_mask:*/ 0)) { |
| debug_printf_parse("parse_stream parse error: " |
| "parse_dollar returned 0 (error)\n"); |
| goto parse_error_exitcode1; |
| } |
| continue; /* get next char */ |
| case '"': |
| ctx.word.has_quoted_part = 1; |
| if (next == '"' && !ctx.pending_redirect) { |
| i_getch(input); /* eat second " */ |
| insert_empty_quoted_str_marker: |
| nommu_addchr(&ctx.as_string, next); |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| continue; /* get next char */ |
| } |
| if (ctx.is_assignment == NOT_ASSIGNMENT) |
| ctx.word.o_expflags |= EXP_FLAG_ESC_GLOB_CHARS; |
| if (!encode_string(&ctx.as_string, &ctx.word, input, '"')) |
| goto parse_error_exitcode1; |
| ctx.word.o_expflags &= ~EXP_FLAG_ESC_GLOB_CHARS; |
| continue; /* get next char */ |
| #if ENABLE_HUSH_TICK |
| case '`': { |
| USE_FOR_NOMMU(unsigned pos;) |
| |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| o_addchr(&ctx.word, '`'); |
| USE_FOR_NOMMU(pos = ctx.word.length;) |
| if (!add_till_backquote(&ctx.word, input, /*in_dquote:*/ 0)) |
| goto parse_error_exitcode1; |
| # if !BB_MMU |
| o_addstr(&ctx.as_string, ctx.word.data + pos); |
| o_addchr(&ctx.as_string, '`'); |
| # endif |
| o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL); |
| //debug_printf_subst("SUBST RES3 '%s'\n", ctx.word.data + pos); |
| continue; /* get next char */ |
| } |
| #endif |
| case ';': |
| #if ENABLE_HUSH_CASE |
| case_semi: |
| #endif |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| done_pipe(&ctx, PIPE_SEQ); |
| #if ENABLE_HUSH_CASE |
| /* Eat multiple semicolons, detect |
| * whether it means something special */ |
| while (1) { |
| ch = i_peek_and_eat_bkslash_nl(input); |
| if (ch != ';') |
| break; |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| if (ctx.ctx_res_w == RES_CASE_BODY) { |
| ctx.ctx_dsemicolon = 1; |
| ctx.ctx_res_w = RES_MATCH; |
| break; |
| } |
| } |
| #endif |
| new_cmd: |
| /* We just finished a cmd. New one may start |
| * with an assignment */ |
| ctx.is_assignment = MAYBE_ASSIGNMENT; |
| debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]); |
| continue; /* get next char */ |
| case '&': |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| if (next == '&') { |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| done_pipe(&ctx, PIPE_AND); |
| } else { |
| done_pipe(&ctx, PIPE_BG); |
| } |
| goto new_cmd; |
| case '|': |
| if (done_word(&ctx)) { |
| goto parse_error_exitcode1; |
| } |
| #if ENABLE_HUSH_CASE |
| if (ctx.ctx_res_w == RES_MATCH) |
| break; /* we are in case's "word | word)" */ |
| #endif |
| if (next == '|') { /* || */ |
| ch = i_getch(input); |
| nommu_addchr(&ctx.as_string, ch); |
| done_pipe(&ctx, PIPE_OR); |
| } else { |
| /* we could pick up a file descriptor choice here |
| * with redirect_opt_num(), but bash doesn't do it. |
| * "echo foo 2| cat" yields "foo 2". */ |
| done_command(&ctx); |
| } |
| goto new_cmd; |
| case '(': |
| #if ENABLE_HUSH_CASE |
| /* "case... in [(]word)..." - skip '(' */ |
| if (ctx.ctx_res_w == RES_MATCH |
| && ctx.command->argv == NULL /* not (word|(... */ |
| && ctx.word.length == 0 /* not word(... */ |
| && ctx.word.has_quoted_part == 0 /* not ""(... */ |
| ) { |
| continue; /* get next char */ |
| } |
| #endif |
| /* fall through */ |
| case '{': { |
| int n = parse_group(&ctx, input, ch); |
| if (n < 0) { |
| goto parse_error_exitcode1; |
| } |
| debug_printf_heredoc("parse_group done, needs heredocs:%d\n", n); |
| heredoc_cnt += n; |
| goto new_cmd; |
| } |
| case ')': |
| #if ENABLE_HUSH_CASE |
| if (ctx.ctx_res_w == RES_MATCH) |
| goto case_semi; |
| #endif |
| case '}': |
| /* proper use of this character is caught by end_trigger: |
| * if we see {, we call parse_group(..., end_trigger='}') |
| * and it will match } earlier (not here). */ |
| G.last_exitcode = 2; |
| syntax_error_unexpected_ch(ch); |
| goto parse_error; |
| default: |
| if (HUSH_DEBUG) |
| bb_error_msg_and_die("BUG: unexpected %c", ch); |
| } |
| } /* while (1) */ |
| |
| parse_error_exitcode1: |
| G.last_exitcode = 1; |
| parse_error: |
| { |
| struct parse_context *pctx; |
| IF_HAS_KEYWORDS(struct parse_context *p2;) |
| |
| /* Clean up allocated tree. |
| * Sample for finding leaks on syntax error recovery path. |
| * Run it from interactive shell, watch pmap `pidof hush`. |
| * while if false; then false; fi; do break; fi |
| * Samples to catch leaks at execution: |
| * while if (true | { true;}); then echo ok; fi; do break; done |
| * while if (true | { true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done |
| */ |
| pctx = &ctx; |
| do { |
| /* Update pipe/command counts, |
| * otherwise freeing may miss some */ |
| done_pipe(pctx, PIPE_SEQ); |
| debug_printf_clean("freeing list %p from ctx %p\n", |
| pctx->list_head, pctx); |
| debug_print_tree(pctx->list_head, 0); |
| free_pipe_list(pctx->list_head); |
| debug_printf_clean("freed list %p\n", pctx->list_head); |
| #if !BB_MMU |
| o_free(&pctx->as_string); |
| #endif |
| IF_HAS_KEYWORDS(p2 = pctx->stack;) |
| if (pctx != &ctx) { |
| free(pctx); |
| } |
| IF_HAS_KEYWORDS(pctx = p2;) |
| } while (HAS_KEYWORDS && pctx); |
| |
| o_free(&ctx.word); |
| #if !BB_MMU |
| if (pstring) |
| *pstring = NULL; |
| #endif |
| debug_leave(); |
| return ERR_PTR; |
| } |
| } |
| |
| |
| /*** Execution routines ***/ |
| |
| /* Expansion can recurse, need forward decls: */ |
| #if !BASH_PATTERN_SUBST && !ENABLE_HUSH_CASE |
| #define expand_string_to_string(str, EXP_flags, do_unbackslash) \ |
| expand_string_to_string(str) |
| #endif |
| static char *expand_string_to_string(const char *str, int EXP_flags, int do_unbackslash); |
| #if ENABLE_HUSH_TICK |
| static int process_command_subs(o_string *dest, const char *s); |
| #endif |
| static int expand_vars_to_list(o_string *output, int n, char *arg); |
| |
| /* expand_strvec_to_strvec() takes a list of strings, expands |
| * all variable references within and returns a pointer to |
| * a list of expanded strings, possibly with larger number |
| * of strings. (Think VAR="a b"; echo $VAR). |
| * This new list is allocated as a single malloc block. |
| * NULL-terminated list of char* pointers is at the beginning of it, |
| * followed by strings themselves. |
| * Caller can deallocate entire list by single free(list). */ |
| |
| /* A horde of its helpers come first: */ |
| |
| static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len) |
| { |
| while (--len >= 0) { |
| char c = *str++; |
| |
| #if ENABLE_HUSH_BRACE_EXPANSION |
| if (c == '{' || c == '}') { |
| /* { -> \{, } -> \} */ |
| o_addchr(o, '\\'); |
| /* And now we want to add { or } and continue: |
| * o_addchr(o, c); |
| * continue; |
| * luckily, just falling through achieves this. |
| */ |
| } |
| #endif |
| o_addchr(o, c); |
| if (c == '\\') { |
| /* \z -> \\\z; \<eol> -> \\<eol> */ |
| o_addchr(o, '\\'); |
| if (len) { |
| len--; |
| o_addchr(o, '\\'); |
| o_addchr(o, *str++); |
| } |
| } |
| } |
| } |
| |
| /* Store given string, finalizing the word and starting new one whenever |
| * we encounter IFS char(s). This is used for expanding variable values. |
| * End-of-string does NOT finalize word: think about 'echo -$VAR-'. |
| * Return in output->ended_in_ifs: |
| * 1 - ended with IFS char, else 0 (this includes case of empty str). |
| */ |
| static int expand_on_ifs(o_string *output, int n, const char *str) |
| { |
| int last_is_ifs = 0; |
| |
| while (1) { |
| int word_len; |
| |
| if (!*str) /* EOL - do not finalize word */ |
| break; |
| word_len = strcspn(str, G.ifs); |
| if (word_len) { |
| /* We have WORD_LEN leading non-IFS chars */ |
| if (!(output->o_expflags & EXP_FLAG_GLOB)) { |
| o_addblock(output, str, word_len); |
| } else { |
| /* Protect backslashes against globbing up :) |
| * Example: "v='\*'; echo b$v" prints "b\*" |
| * (and does not try to glob on "*") |
| */ |
| o_addblock_duplicate_backslash(output, str, word_len); |
| /*/ Why can't we do it easier? */ |
| /*o_addblock(output, str, word_len); - WRONG: "v='\*'; echo Z$v" prints "Z*" instead of "Z\*" */ |
| /*o_addqblock(output, str, word_len); - WRONG: "v='*'; echo Z$v" prints "Z*" instead of Z* files */ |
| } |
| last_is_ifs = 0; |
| str += word_len; |
| if (!*str) /* EOL - do not finalize word */ |
| break; |
| } |
| |
| /* We know str here points to at least one IFS char */ |
| last_is_ifs = 1; |
| str += strspn(str, G.ifs_whitespace); /* skip IFS whitespace chars */ |
| if (!*str) /* EOL - do not finalize word */ |
| break; |
| |
| if (G.ifs_whitespace != G.ifs /* usually false ($IFS is usually all whitespace), */ |
| && strchr(G.ifs, *str) /* the second check would fail */ |
| ) { |
| /* This is a non-whitespace $IFS char */ |
| /* Skip it and IFS whitespace chars, start new word */ |
| str++; |
| str += strspn(str, G.ifs_whitespace); |
| goto new_word; |
| } |
| |
| /* Start new word... but not always! */ |
| /* Case "v=' a'; echo ''$v": we do need to finalize empty word: */ |
| if (output->has_quoted_part |
| /* |
| * Case "v=' a'; echo $v": |
| * here nothing precedes the space in $v expansion, |
| * therefore we should not finish the word |
| * (IOW: if there *is* word to finalize, only then do it): |
| * It's okay if this accesses the byte before first argv[]: |
| * past call to o_save_ptr() cleared it to zero byte |
| * (grep for -prev-ifs-check-). |
| */ |
| || output->data[output->length - 1] |
| ) { |
| new_word: |
| o_addchr(output, '\0'); |
| debug_print_list("expand_on_ifs", output, n); |
| n = o_save_ptr(output, n); |
| } |
| } |
| |
| output->ended_in_ifs = last_is_ifs; |
| debug_print_list("expand_on_ifs[1]", output, n); |
| return n; |
| } |
| |
| /* Helper to expand $((...)) and heredoc body. These act as if |
| * they are in double quotes, with the exception that they are not :). |
| * Just the rules are similar: "expand only $var and `cmd`" |
| * |
| * Returns malloced string. |
| * As an optimization, we return NULL if expansion is not needed. |
| */ |
| static char *encode_then_expand_string(const char *str) |
| { |
| char *exp_str; |
| struct in_str input; |
| o_string dest = NULL_O_STRING; |
| const char *cp; |
| |
| cp = str; |
| for (;;) { |
| if (!*cp) return NULL; /* string has no special chars */ |
| if (*cp == '$') break; |
| if (*cp == '\\') break; |
| #if ENABLE_HUSH_TICK |
| if (*cp == '`') break; |
| #endif |
| cp++; |
| } |
| |
| /* We need to expand. Example: |
| * echo $(($a + `echo 1`)) $((1 + $((2)) )) |
| */ |
| setup_string_in_str(&input, str); |
| encode_string(NULL, &dest, &input, EOF); |
| //TODO: error check (encode_string returns 0 on error)? |
| //bb_error_msg("'%s' -> '%s'", str, dest.data); |
| exp_str = expand_string_to_string(dest.data, |
| EXP_FLAG_ESC_GLOB_CHARS, |
| /*unbackslash:*/ 1 |
| ); |
| //bb_error_msg("'%s' -> '%s'", dest.data, exp_str); |
| o_free(&dest); |
| return exp_str; |
| } |
| |
| static const char *first_special_char_in_vararg(const char *cp) |
| { |
| for (;;) { |
| if (!*cp) return NULL; /* string has no special chars */ |
| if (*cp == '$') return cp; |
| if (*cp == '\\') return cp; |
| if (*cp == '\'') return cp; |
| if (*cp == '"') return cp; |
| #if ENABLE_HUSH_TICK |
| if (*cp == '`') return cp; |
| #endif |
| /* dquoted "${x:+ARG}" should not glob, therefore |
| * '*' et al require some non-literal processing: */ |
| if (*cp == '*') return cp; |
| if (*cp == '?') return cp; |
| if (*cp == '[') return cp; |
| cp++; |
| } |
| } |
| |
| /* Expanding ARG in ${var#ARG}, ${var%ARG}, or ${var/ARG/ARG}. |
| * These can contain single- and double-quoted strings, |
| * and treated as if the ARG string is initially unquoted. IOW: |
| * ${var#ARG} and "${var#ARG}" treat ARG the same (ARG can even be |
| * a dquoted string: "${var#"zz"}"), the difference only comes later |
| * (word splitting and globbing of the ${var...} result). |
| */ |
| #if !BASH_PATTERN_SUBST |
| #define encode_then_expand_vararg(str, handle_squotes, do_unbackslash) \ |
| encode_then_expand_vararg(str, handle_squotes) |
| #endif |
| static char *encode_then_expand_vararg(const char *str, int handle_squotes, int do_unbackslash) |
| { |
| #if !BASH_PATTERN_SUBST && ENABLE_HUSH_CASE |
| const int do_unbackslash = 0; |
| #endif |
| char *exp_str; |
| struct in_str input; |
| o_string dest = NULL_O_STRING; |
| |
| if (!first_special_char_in_vararg(str)) { |
| /* string has no special chars */ |
| return NULL; |
| } |
| |
| setup_string_in_str(&input, str); |
| dest.data = xzalloc(1); /* start as "", not as NULL */ |
| exp_str = NULL; |
| |
| for (;;) { |
| int ch; |
| |
| ch = i_getch(&input); |
| debug_printf_parse("%s: ch=%c (%d) escape=%d\n", |
| __func__, ch, ch, !!dest.o_expflags); |
| |
| if (!dest.o_expflags) { |
| if (ch == EOF) |
| break; |
| if (handle_squotes && ch == '\'') { |
| if (!add_till_single_quote_dquoted(&dest, &input)) |
| goto ret; /* error */ |
| continue; |
| } |
| } |
| if (ch == EOF) { |
| syntax_error_unterm_ch('"'); |
| goto ret; /* error */ |
| } |
| if (ch == '"') { |
| dest.o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS; |
| continue; |
| } |
| if (ch == '\\') { |
| ch = i_getch(&input); |
| if (ch == EOF) { |
| //example? error message? syntax_error_unterm_ch('"'); |
| debug_printf_parse("%s: error: \\<eof>\n", __func__); |
| goto ret; |
| } |
| o_addqchr(&dest, ch); |
| continue; |
| } |
| if (ch == '$') { |
| if (parse_dollar_squote(NULL, &dest, &input)) |
| continue; |
| if (!parse_dollar(NULL, &dest, &input, /*quote_mask:*/ 0x80)) { |
| debug_printf_parse("%s: error: parse_dollar returned 0 (error)\n", __func__); |
| goto ret; |
| } |
| continue; |
| } |
| #if ENABLE_HUSH_TICK |
| if (ch == '`') { |
| //unsigned pos = dest->length; |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(&dest, 0x80 | '`'); |
| if (!add_till_backquote(&dest, &input, |
| /*in_dquote:*/ dest.o_expflags /* nonzero if EXP_FLAG_ESC_GLOB_CHARS set */ |
| ) |
| ) { |
| goto ret; /* error */ |
| } |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos); |
| continue; |
| } |
| #endif |
| o_addQchr(&dest, ch); |
| } /* for (;;) */ |
| |
| debug_printf_parse("encode: '%s' -> '%s'\n", str, dest.data); |
| exp_str = expand_string_to_string(dest.data, |
| do_unbackslash ? EXP_FLAG_ESC_GLOB_CHARS : 0, |
| do_unbackslash |
| ); |
| ret: |
| debug_printf_parse("expand: '%s' -> '%s'\n", dest.data, exp_str); |
| o_free(&dest); |
| return exp_str; |
| } |
| |
| /* Expanding ARG in ${var+ARG}, ${var-ARG} |
| */ |
| static NOINLINE int encode_then_append_var_plusminus(o_string *output, int n, |
| char *str, int dquoted) |
| { |
| struct in_str input; |
| o_string dest = NULL_O_STRING; |
| |
| if (!first_special_char_in_vararg(str) |
| && '\0' == str[strcspn(str, G.ifs)] |
| ) { |
| /* string has no special chars |
| * && string has no $IFS chars |
| */ |
| if (dquoted) { |
| /* Prints 1 (quoted expansion is a "" word, not nothing): |
| * set -- "${notexist-}"; echo $# |
| */ |
| output->has_quoted_part = 1; |
| } |
| return expand_vars_to_list(output, n, str); |
| } |
| |
| setup_string_in_str(&input, str); |
| |
| for (;;) { |
| int ch; |
| |
| ch = i_getch(&input); |
| debug_printf_parse("%s: ch=%c (%d) escape=%x\n", |
| __func__, ch, ch, dest.o_expflags); |
| |
| if (!dest.o_expflags) { |
| if (ch == EOF) |
| break; |
| if (!dquoted && strchr(G.ifs, ch)) { |
| /* PREFIX${x:d${e}f ...} and we met space: expand "d${e}f" and start new word. |
| * do not assume we are at the start of the word (PREFIX above). |
| */ |
| if (dest.data) { |
| n = expand_vars_to_list(output, n, dest.data); |
| o_free_and_set_NULL(&dest); |
| o_addchr(output, '\0'); |
| n = o_save_ptr(output, n); /* create next word */ |
| } else |
| if (output->length != o_get_last_ptr(output, n) |
| || output->has_quoted_part |
| ) { |
| /* For these cases: |
| * f() { for i; do echo "|$i|"; done; }; x=x |
| * f a${x:+ }b # 1st condition |
| * |a| |
| * |b| |
| * f ""${x:+ }b # 2nd condition |
| * || |
| * |b| |
| */ |
| o_addchr(output, '\0'); |
| n = o_save_ptr(output, n); /* create next word */ |
| } |
| continue; |
| } |
| if (!dquoted && ch == '\'') { |
| if (!add_till_single_quote_dquoted(&dest, &input)) |
| goto ret; /* error */ |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| continue; |
| } |
| } |
| if (ch == EOF) { |
| syntax_error_unterm_ch('"'); |
| goto ret; /* error */ |
| } |
| if (ch == '"') { |
| dest.o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS; |
| if (dest.o_expflags) { |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| } |
| continue; |
| } |
| if (ch == '\\') { |
| ch = i_getch(&input); |
| if (ch == EOF) { |
| //example? error message? syntax_error_unterm_ch('"'); |
| debug_printf_parse("%s: error: \\<eof>\n", __func__); |
| goto ret; |
| } |
| o_addqchr(&dest, ch); |
| continue; |
| } |
| if (ch == '$') { |
| if (!parse_dollar(NULL, &dest, &input, /*quote_mask:*/ (dest.o_expflags || dquoted) ? 0x80 : 0)) { |
| debug_printf_parse("%s: error: parse_dollar returned 0 (error)\n", __func__); |
| goto ret; |
| } |
| continue; |
| } |
| #if ENABLE_HUSH_TICK |
| if (ch == '`') { |
| //unsigned pos = dest->length; |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(&dest, (dest.o_expflags || dquoted) ? 0x80 | '`' : '`'); |
| if (!add_till_backquote(&dest, &input, |
| /*in_dquote:*/ dest.o_expflags /* nonzero if EXP_FLAG_ESC_GLOB_CHARS set */ |
| ) |
| ) { |
| goto ret; /* error */ |
| } |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos); |
| continue; |
| } |
| #endif |
| if (dquoted) { |
| /* Always glob-protect if in dquotes: |
| * x=x; echo "${x:+/bin/c*}" - prints: /bin/c* |
| * x=x; echo "${x:+"/bin/c*"}" - prints: /bin/c* |
| */ |
| o_addqchr(&dest, ch); |
| } else { |
| /* Glob-protect only if char is quoted: |
| * x=x; echo ${x:+/bin/c*} - prints many filenames |
| * x=x; echo ${x:+"/bin/c*"} - prints: /bin/c* |
| */ |
| o_addQchr(&dest, ch); |
| } |
| } /* for (;;) */ |
| |
| if (dest.data) { |
| n = expand_vars_to_list(output, n, dest.data); |
| } |
| ret: |
| o_free(&dest); |
| return n; |
| } |
| |
| #if ENABLE_FEATURE_SH_MATH |
| static arith_t expand_and_evaluate_arith(const char *arg, const char **errmsg_p) |
| { |
| arith_state_t math_state; |
| arith_t res; |
| char *exp_str; |
| |
| math_state.lookupvar = get_local_var_value; |
| math_state.setvar = set_local_var_from_halves; |
| //math_state.endofname = endofname; |
| exp_str = encode_then_expand_string(arg); |
| res = arith(&math_state, exp_str ? exp_str : arg); |
| free(exp_str); |
| if (errmsg_p) |
| *errmsg_p = math_state.errmsg; |
| if (math_state.errmsg) |
| msg_and_die_if_script(math_state.errmsg); |
| return res; |
| } |
| #endif |
| |
| #if BASH_PATTERN_SUBST |
| /* ${var/[/]pattern[/repl]} helpers */ |
| static char *strstr_pattern(char *val, const char *pattern, int *size) |
| { |
| int first_escaped = (pattern[0] == '\\' && pattern[1]); |
| /* "first_escaped" trick allows to treat e.g. "\*no_glob_chars" |
| * as literal too (as it is semi-common, and easy to accomodate |
| * by just using str + 1). |
| */ |
| int sz = strcspn(pattern + first_escaped * 2, "*?[\\"); |
| if ((pattern + first_escaped * 2)[sz] == '\0') { |
| /* Optimization for trivial patterns. |
| * Testcase for very slow replace (performs about 22k replaces): |
| * x=:::::::::::::::::::::: |
| * x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;echo ${#x} |
| * echo "${x//:/|}" |
| */ |
| *size = sz + first_escaped; |
| return strstr(val, pattern + first_escaped); |
| } |
| |
| while (1) { |
| char *end = scan_and_match(val, pattern, SCAN_MOVE_FROM_RIGHT + SCAN_MATCH_LEFT_HALF); |
| debug_printf_varexp("val:'%s' pattern:'%s' end:'%s'\n", val, pattern, end); |
| if (end) { |
| *size = end - val; |
| return val; |
| } |
| if (*val == '\0') |
| return NULL; |
| /* Optimization: if "*pat" did not match the start of "string", |
| * we know that "tring", "ring" etc will not match too: |
| */ |
| if (pattern[0] == '*') |
| return NULL; |
| val++; |
| } |
| } |
| static char *replace_pattern(char *val, const char *pattern, const char *repl, char exp_op) |
| { |
| char *result = NULL; |
| unsigned res_len = 0; |
| unsigned repl_len = strlen(repl); |
| |
| /* Null pattern never matches, including if "var" is empty */ |
| if (!pattern[0]) |
| return result; /* NULL, no replaces happened */ |
| |
| while (1) { |
| int size; |
| char *s = strstr_pattern(val, pattern, &size); |
| if (!s) |
| break; |
| |
| result = xrealloc(result, res_len + (s - val) + repl_len + 1); |
| strcpy(mempcpy(result + res_len, val, s - val), repl); |
| res_len += (s - val) + repl_len; |
| debug_printf_varexp("val:'%s' s:'%s' result:'%s'\n", val, s, result); |
| |
| val = s + size; |
| if (exp_op == '/') |
| break; |
| } |
| if (*val && result) { |
| result = xrealloc(result, res_len + strlen(val) + 1); |
| strcpy(result + res_len, val); |
| debug_printf_varexp("val:'%s' result:'%s'\n", val, result); |
| } |
| debug_printf_varexp("result:'%s'\n", result); |
| return result; |
| } |
| #endif /* BASH_PATTERN_SUBST */ |
| |
| static int append_str_maybe_ifs_split(o_string *output, int n, |
| int first_ch, const char *val) |
| { |
| if (!(first_ch & 0x80)) { /* unquoted $VAR */ |
| debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val, |
| !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)); |
| if (val && val[0]) |
| n = expand_on_ifs(output, n, val); |
| } else { /* quoted "$VAR" */ |
| output->has_quoted_part = 1; |
| debug_printf_expand("quoted '%s', output->o_escape:%d\n", val, |
| !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)); |
| if (val && val[0]) |
| o_addQstr(output, val); |
| } |
| return n; |
| } |
| |
| /* Handle <SPECIAL_VAR_SYMBOL>varname...<SPECIAL_VAR_SYMBOL> construct. |
| */ |
| static NOINLINE int expand_one_var(o_string *output, int n, |
| int first_ch, char *arg, char **pp) |
| { |
| const char *val; |
| char *to_be_freed; |
| char *p; |
| char *var; |
| char exp_op; |
| char exp_save = exp_save; /* for compiler */ |
| char *exp_saveptr; /* points to expansion operator */ |
| char *exp_word = exp_word; /* for compiler */ |
| char arg0; |
| |
| val = NULL; |
| to_be_freed = NULL; |
| p = *pp; |
| *p = '\0'; /* replace trailing SPECIAL_VAR_SYMBOL */ |
| var = arg; |
| exp_saveptr = arg[1] ? strchr(VAR_ENCODED_SUBST_OPS, arg[1]) : NULL; |
| arg0 = arg[0]; |
| arg[0] = (arg0 & 0x7f); |
| exp_op = 0; |
| |
| if (arg[0] == '#' && arg[1] /* ${#...} but not ${#} */ |
| && (!exp_saveptr /* and ( not(${#<op_char>...}) */ |
| || (arg[2] == '\0' && strchr(SPECIAL_VARS_STR, arg[1])) /* or ${#C} "len of $C" ) */ |
| ) /* NB: skipping ^^^specvar check mishandles ${#::2} */ |
| ) { |
| /* It must be length operator: ${#var} */ |
| var++; |
| exp_op = 'L'; |
| } else { |
| /* Maybe handle parameter expansion */ |
| if (exp_saveptr /* if 2nd char is one of expansion operators */ |
| && strchr(NUMERIC_SPECVARS_STR, arg[0]) /* 1st char is special variable */ |
| ) { |
| /* ${?:0}, ${#[:]%0} etc */ |
| exp_saveptr = var + 1; |
| } else { |
| /* ${?}, ${var}, ${var:0}, ${var[:]%0} etc */ |
| exp_saveptr = var+1 + strcspn(var+1, VAR_ENCODED_SUBST_OPS); |
| } |
| exp_op = exp_save = *exp_saveptr; |
| if (exp_op) { |
| exp_word = exp_saveptr + 1; |
| if (exp_op == ':') { |
| exp_op = *exp_word++; |
| //TODO: try ${var:} and ${var:bogus} in non-bash config |
| if (BASH_SUBSTR |
| && (!exp_op || !strchr(MINUS_PLUS_EQUAL_QUESTION, exp_op)) |
| ) { |
| /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */ |
| exp_op = ':'; |
| exp_word--; |
| } |
| } |
| *exp_saveptr = '\0'; |
| } /* else: it's not an expansion op, but bare ${var} */ |
| } |
| |
| /* Look up the variable in question */ |
| if (isdigit(var[0])) { |
| /* parse_dollar should have vetted var for us */ |
| int nn = xatoi_positive(var); |
| if (nn < G.global_argc) |
| val = G.global_argv[nn]; |
| /* else val remains NULL: $N with too big N */ |
| } else { |
| switch (var[0]) { |
| case '$': /* pid */ |
| val = utoa(G.root_pid); |
| break; |
| case '!': /* bg pid */ |
| val = G.last_bg_pid ? utoa(G.last_bg_pid) : ""; |
| break; |
| case '?': /* exitcode */ |
| val = utoa(G.last_exitcode); |
| break; |
| case '#': /* argc */ |
| val = utoa(G.global_argc ? G.global_argc-1 : 0); |
| break; |
| case '-': { /* active options */ |
| /* Check set_mode() to see what option chars we support */ |
| char *cp; |
| val = cp = G.optstring_buf; |
| if (G.o_opt[OPT_O_ERREXIT]) |
| *cp++ = 'e'; |
| if (G_interactive_fd) |
| *cp++ = 'i'; |
| if (G_x_mode) |
| *cp++ = 'x'; |
| /* If G.o_opt[OPT_O_NOEXEC] is true, |
| * commands read but are not executed, |
| * so $- can not execute too, 'n' is never seen in $-. |
| */ |
| if (G.opt_c) |
| *cp++ = 'c'; |
| if (G.opt_s) |
| *cp++ = 's'; |
| *cp = '\0'; |
| break; |
| } |
| default: |
| val = get_local_var_value(var); |
| } |
| } |
| |
| /* Handle any expansions */ |
| if (exp_op == 'L') { |
| reinit_unicode_for_hush(); |
| debug_printf_expand("expand: length(%s)=", val); |
| val = utoa(val ? unicode_strlen(val) : 0); |
| debug_printf_expand("%s\n", val); |
| } else if (exp_op) { |
| if (exp_op == '%' || exp_op == '#') { |
| /* Standard-mandated substring removal ops: |
| * ${parameter%word} - remove smallest suffix pattern |
| * ${parameter%%word} - remove largest suffix pattern |
| * ${parameter#word} - remove smallest prefix pattern |
| * ${parameter##word} - remove largest prefix pattern |
| * |
| * Word is expanded to produce a glob pattern. |
| * Then var's value is matched to it and matching part removed. |
| */ |
| /* bash compat: if x is "" and no shrinking of it is possible, |
| * inner ${...} is not evaluated. Example: |
| * unset b; : ${a%${b=B}}; echo $b |
| * assignment b=B only happens if $a is not "". |
| */ |
| if (val && val[0]) { |
| char *t; |
| char *exp_exp_word; |
| char *loc; |
| unsigned scan_flags = pick_scan(exp_op, *exp_word); |
| if (exp_op == *exp_word) /* ## or %% */ |
| exp_word++; |
| debug_printf_expand("expand: exp_word:'%s'\n", exp_word); |
| exp_exp_word = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 0); |
| if (exp_exp_word) |
| exp_word = exp_exp_word; |
| debug_printf_expand("expand: exp_word:'%s'\n", exp_word); |
| /* |
| * HACK ALERT. We depend here on the fact that |
| * G.global_argv and results of utoa and get_local_var_value |
| * are actually in writable memory: |
| * scan_and_match momentarily stores NULs there. |
| */ |
| t = (char*)val; |
| loc = scan_and_match(t, exp_word, scan_flags); |
| debug_printf_expand("op:%c str:'%s' pat:'%s' res:'%s'\n", exp_op, t, exp_word, loc); |
| free(exp_exp_word); |
| if (loc) { /* match was found */ |
| if (scan_flags & SCAN_MATCH_LEFT_HALF) /* #[#] */ |
| val = loc; /* take right part */ |
| else /* %[%] */ |
| val = to_be_freed = xstrndup(val, loc - val); /* left */ |
| } |
| } |
| } |
| #if BASH_PATTERN_SUBST |
| else if (exp_op == '/' || exp_op == '\\') { |
| /* It's ${var/[/]pattern[/repl]} thing. |
| * Note that in encoded form it has TWO parts: |
| * var/pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL> |
| * and if // is used, it is encoded as \: |
| * var\pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL> |
| */ |
| /* bash compat: if var is "", both pattern and repl |
| * are still evaluated, if it is unset, then not: |
| * unset b; a=; : ${a/z/${b=3}}; echo $b # b=3 |
| * unset b; unset a; : ${a/z/${b=3}}; echo $b # b not set |
| */ |
| if (val /*&& val[0]*/) { |
| /* pattern uses non-standard expansion. |
| * repl should be unbackslashed and globbed |
| * by the usual expansion rules: |
| * >az >bz |
| * v='a bz'; echo "${v/a*z/a*z}" #prints "a*z" |
| * v='a bz'; echo "${v/a*z/\z}" #prints "z" |
| * v='a bz'; echo ${v/a*z/a*z} #prints "az" |
| * v='a bz'; echo ${v/a*z/\z} #prints "z" |
| * (note that a*z _pattern_ is never globbed!) |
| */ |
| char *pattern, *repl, *t; |
| pattern = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 0); |
| if (!pattern) |
| pattern = xstrdup(exp_word); |
| debug_printf_varexp("pattern:'%s'->'%s'\n", exp_word, pattern); |
| *p++ = SPECIAL_VAR_SYMBOL; |
| exp_word = p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| *p = '\0'; |
| repl = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 1); |
| debug_printf_varexp("repl:'%s'->'%s'\n", exp_word, repl); |
| /* HACK ALERT. We depend here on the fact that |
| * G.global_argv and results of utoa and get_local_var_value |
| * are actually in writable memory: |
| * replace_pattern momentarily stores NULs there. */ |
| t = (char*)val; |
| to_be_freed = replace_pattern(t, |
| pattern, |
| (repl ? repl : exp_word), |
| exp_op); |
| if (to_be_freed) /* at least one replace happened */ |
| val = to_be_freed; |
| free(pattern); |
| free(repl); |
| } else { |
| /* Unset variable always gives nothing */ |
| // a=; echo ${a/*/w} # "w" |
| // unset a; echo ${a/*/w} # "" |
| /* Just skip "replace" part */ |
| *p++ = SPECIAL_VAR_SYMBOL; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| *p = '\0'; |
| } |
| } |
| #endif /* BASH_PATTERN_SUBST */ |
| else if (exp_op == ':') { |
| #if BASH_SUBSTR && ENABLE_FEATURE_SH_MATH |
| /* It's ${var:N[:M]} bashism. |
| * Note that in encoded form it has TWO parts: |
| * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL> |
| */ |
| arith_t beg, len; |
| unsigned vallen; |
| const char *errmsg; |
| |
| beg = expand_and_evaluate_arith(exp_word, &errmsg); |
| if (errmsg) |
| goto empty_result; |
| debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg); |
| *p++ = SPECIAL_VAR_SYMBOL; |
| exp_word = p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| *p = '\0'; |
| vallen = val ? strlen(val) : 0; |
| if (beg < 0) { |
| /* negative beg counts from the end */ |
| beg = (arith_t)vallen + beg; |
| } |
| /* If expansion will be empty, do not even evaluate len */ |
| if (!val || beg < 0 || beg > vallen) { |
| /* Why > vallen, not >=? bash: |
| * unset b; a=ab; : ${a:2:${b=3}}; echo $b # "", b=3 (!!!) |
| * unset b; a=a; : ${a:2:${b=3}}; echo $b # "", b not set |
| */ |
| goto empty_result; |
| } |
| len = expand_and_evaluate_arith(exp_word, &errmsg); |
| if (errmsg) |
| goto empty_result; |
| debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len); |
| debug_printf_varexp("from val:'%s'\n", val); |
| if (len < 0) { |
| /* in bash, len=-n means strlen()-n */ |
| len = (arith_t)vallen - beg + len; |
| if (len < 0) /* bash compat */ |
| msg_and_die_if_script("%s: substring expression < 0", var); |
| } |
| if (len <= 0 || !val /*|| beg >= vallen*/) { |
| empty_result: |
| val = NULL; |
| } else { |
| /* Paranoia. What if user entered 9999999999999 |
| * which fits in arith_t but not int? */ |
| if (len > INT_MAX) |
| len = INT_MAX; |
| val = to_be_freed = xstrndup(val + beg, len); |
| } |
| debug_printf_varexp("val:'%s'\n", val); |
| #else /* not (HUSH_SUBSTR_EXPANSION && FEATURE_SH_MATH) */ |
| msg_and_die_if_script("malformed ${%s:...}", var); |
| val = NULL; |
| #endif |
| } else { /* one of "-=+?" */ |
| /* Standard-mandated substitution ops: |
| * ${var?word} - indicate error if unset |
| * If var is unset, word (or a message indicating it is unset |
| * if word is null) is written to standard error |
| * and the shell exits with a non-zero exit status. |
| * Otherwise, the value of var is substituted. |
| * ${var-word} - use default value |
| * If var is unset, word is substituted. |
| * ${var=word} - assign and use default value |
| * If var is unset, word is assigned to var. |
| * In all cases, final value of var is substituted. |
| * ${var+word} - use alternative value |
| * If var is unset, null is substituted. |
| * Otherwise, word is substituted. |
| * |
| * Word is subjected to tilde expansion, parameter expansion, |
| * command substitution, and arithmetic expansion. |
| * If word is not needed, it is not expanded. |
| * |
| * Colon forms (${var:-word}, ${var:=word} etc) do the same, |
| * but also treat null var as if it is unset. |
| * |
| * Word-splitting and single quote behavior: |
| * |
| * $ f() { for i; do echo "|$i|"; done; } |
| * |
| * $ x=; f ${x:?'x y' z}; echo $? |
| * bash: x: x y z # neither f nor "echo $?" executes |
| * (if interactive, bash does not exit, but merely aborts to prompt. $? is set to 1) |
| * $ x=; f "${x:?'x y' z}" |
| * bash: x: x y z # dash prints: dash: x: 'x y' z |
| * |
| * $ x=; f ${x:='x y' z} |
| * |x| |
| * |y| |
| * |z| |
| * $ x=; f "${x:='x y' z}" |
| * |'x y' z| |
| * |
| * $ x=x; f ${x:+'x y' z} |
| * |x y| |
| * |z| |
| * $ x=x; f "${x:+'x y' z}" |
| * |'x y' z| |
| * |
| * $ x=; f ${x:-'x y' z} |
| * |x y| |
| * |z| |
| * $ x=; f "${x:-'x y' z}" |
| * |'x y' z| |
| */ |
| int use_word = (!val || ((exp_save == ':') && !val[0])); |
| if (exp_op == '+') |
| use_word = !use_word; |
| debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op, |
| (exp_save == ':') ? "true" : "false", use_word); |
| if (use_word) { |
| if (exp_op == '+' || exp_op == '-') { |
| /* ${var+word} - use alternative value */ |
| /* ${var-word} - use default value */ |
| n = encode_then_append_var_plusminus(output, n, exp_word, |
| /*dquoted:*/ (arg0 & 0x80) |
| ); |
| val = NULL; |
| } else { |
| /* ${var?word} - indicate error if unset */ |
| /* ${var=word} - assign and use default value */ |
| to_be_freed = encode_then_expand_vararg(exp_word, |
| /*handle_squotes:*/ !(arg0 & 0x80), |
| /*unbackslash:*/ 0 |
| ); |
| if (to_be_freed) |
| exp_word = to_be_freed; |
| if (exp_op == '?') { |
| /* mimic bash message */ |
| msg_and_die_if_script("%s: %s", |
| var, |
| exp_word[0] |
| ? exp_word |
| : "parameter null or not set" |
| /* ash has more specific messages, a-la: */ |
| /*: (exp_save == ':' ? "parameter null or not set" : "parameter not set")*/ |
| ); |
| //TODO: how interactive bash aborts expansion mid-command? |
| //It aborts the entire line, returns to prompt: |
| // $ f() { for i; do echo "|$i|"; done; }; x=; f "${x:?'x y' z}"; echo YO |
| // bash: x: x y z |
| // $ |
| // ("echo YO" is not executed, neither the f function call) |
| } else { |
| val = exp_word; |
| } |
| if (exp_op == '=') { |
| /* ${var=[word]} or ${var:=[word]} */ |
| if (isdigit(var[0]) || var[0] == '#') { |
| /* mimic bash message */ |
| msg_and_die_if_script("$%s: cannot assign in this way", var); |
| val = NULL; |
| } else { |
| char *new_var = xasprintf("%s=%s", var, val); |
| set_local_var(new_var, /*flag:*/ 0); |
| } |
| } |
| } |
| } |
| } /* one of "-=+?" */ |
| |
| *exp_saveptr = exp_save; |
| } /* if (exp_op) */ |
| |
| arg[0] = arg0; |
| *pp = p; |
| |
| n = append_str_maybe_ifs_split(output, n, first_ch, val); |
| |
| free(to_be_freed); |
| return n; |
| } |
| |
| /* Expand all variable references in given string, adding words to list[] |
| * at n, n+1,... positions. Return updated n (so that list[n] is next one |
| * to be filled). This routine is extremely tricky: has to deal with |
| * variables/parameters with whitespace, $* and $@, and constructs like |
| * 'echo -$*-'. If you play here, you must run testsuite afterwards! */ |
| static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg) |
| { |
| /* output->o_expflags & EXP_FLAG_SINGLEWORD (0x80) if we are in |
| * expansion of right-hand side of assignment == 1-element expand. |
| */ |
| char cant_be_null = 0; /* only bit 0x80 matters */ |
| char *p; |
| |
| debug_printf_expand("expand_vars_to_list: arg:'%s' singleword:%x\n", arg, |
| !!(output->o_expflags & EXP_FLAG_SINGLEWORD)); |
| debug_print_list("expand_vars_to_list[0]", output, n); |
| |
| while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) { |
| char first_ch; |
| #if ENABLE_FEATURE_SH_MATH |
| char arith_buf[sizeof(arith_t)*3 + 2]; |
| #endif |
| |
| if (output->ended_in_ifs) { |
| o_addchr(output, '\0'); |
| n = o_save_ptr(output, n); |
| output->ended_in_ifs = 0; |
| } |
| |
| o_addblock(output, arg, p - arg); |
| debug_print_list("expand_vars_to_list[1]", output, n); |
| arg = ++p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| |
| /* Fetch special var name (if it is indeed one of them) |
| * and quote bit, force the bit on if singleword expansion - |
| * important for not getting v=$@ expand to many words. */ |
| first_ch = arg[0] | (output->o_expflags & EXP_FLAG_SINGLEWORD); |
| |
| /* Is this variable quoted and thus expansion can't be null? |
| * "$@" is special. Even if quoted, it can still |
| * expand to nothing (not even an empty string), |
| * thus it is excluded. */ |
| if ((first_ch & 0x7f) != '@') |
| cant_be_null |= first_ch; |
| |
| switch (first_ch & 0x7f) { |
| /* Highest bit in first_ch indicates that var is double-quoted */ |
| case '*': |
| case '@': { |
| int i; |
| if (!G.global_argv[1]) |
| break; |
| i = 1; |
| cant_be_null |= first_ch; /* do it for "$@" _now_, when we know it's not empty */ |
| if (!(first_ch & 0x80)) { /* unquoted $* or $@ */ |
| while (G.global_argv[i]) { |
| n = expand_on_ifs(output, n, G.global_argv[i]); |
| debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1); |
| if (G.global_argv[i++][0] && G.global_argv[i]) { |
| /* this argv[] is not empty and not last: |
| * put terminating NUL, start new word */ |
| o_addchr(output, '\0'); |
| debug_print_list("expand_vars_to_list[2]", output, n); |
| n = o_save_ptr(output, n); |
| debug_print_list("expand_vars_to_list[3]", output, n); |
| } |
| } |
| } else |
| /* If EXP_FLAG_SINGLEWORD, we handle assignment 'a=....$@.....' |
| * and in this case should treat it like '$*' - see 'else...' below */ |
| if (first_ch == (char)('@'|0x80) /* quoted $@ */ |
| && !(output->o_expflags & EXP_FLAG_SINGLEWORD) /* not v="$@" case */ |
| ) { |
| while (1) { |
| o_addQstr(output, G.global_argv[i]); |
| if (++i >= G.global_argc) |
| break; |
| o_addchr(output, '\0'); |
| debug_print_list("expand_vars_to_list[4]", output, n); |
| n = o_save_ptr(output, n); |
| } |
| } else { /* quoted $* (or v="$@" case): add as one word */ |
| while (1) { |
| o_addQstr(output, G.global_argv[i]); |
| if (!G.global_argv[++i]) |
| break; |
| if (G.ifs[0]) |
| o_addchr(output, G.ifs[0]); |
| } |
| output->has_quoted_part = 1; |
| } |
| break; |
| } |
| case SPECIAL_VAR_SYMBOL: { |
| /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */ |
| /* "Empty variable", used to make "" etc to not disappear */ |
| output->has_quoted_part = 1; |
| cant_be_null = 0x80; |
| arg++; |
| break; |
| } |
| case SPECIAL_VAR_QUOTED_SVS: |
| /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_QUOTED_SVS><SPECIAL_VAR_SYMBOL> */ |
| /* "^C variable", represents literal ^C char (possible in scripts) */ |
| o_addchr(output, SPECIAL_VAR_SYMBOL); |
| arg++; |
| break; |
| #if ENABLE_HUSH_TICK |
| case '`': { |
| /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */ |
| o_string subst_result = NULL_O_STRING; |
| |
| *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */ |
| arg++; |
| /* Can't just stuff it into output o_string, |
| * expanded result may need to be globbed |
| * and $IFS-split */ |
| debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch); |
| G.last_exitcode = process_command_subs(&subst_result, arg); |
| G.expand_exitcode = G.last_exitcode; |
| debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data); |
| n = append_str_maybe_ifs_split(output, n, first_ch, subst_result.data); |
| o_free(&subst_result); |
| break; |
| } |
| #endif |
| #if ENABLE_FEATURE_SH_MATH |
| case '+': { |
| /* <SPECIAL_VAR_SYMBOL>+arith<SPECIAL_VAR_SYMBOL> */ |
| arith_t res; |
| |
| arg++; /* skip '+' */ |
| *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */ |
| debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch); |
| res = expand_and_evaluate_arith(arg, NULL); |
| debug_printf_subst("ARITH RES '"ARITH_FMT"'\n", res); |
| sprintf(arith_buf, ARITH_FMT, res); |
| if (res < 0 |
| && first_ch == (char)('+'|0x80) |
| /* && (output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS) */ |
| ) { |
| /* Quoted negative ariths, like filename[0"$((-9))"], |
| * should not be interpreted as glob ranges. |
| * Convert leading '-' to '\-': |
| */ |
| o_grow_by(output, 1); |
| output->data[output->length++] = '\\'; |
| } |
| o_addstr(output, arith_buf); |
| break; |
| } |
| #endif |
| default: |
| /* <SPECIAL_VAR_SYMBOL>varname[ops]<SPECIAL_VAR_SYMBOL> */ |
| n = expand_one_var(output, n, first_ch, arg, &p); |
| break; |
| } /* switch (char after <SPECIAL_VAR_SYMBOL>) */ |
| |
| /* Restore NULL'ed SPECIAL_VAR_SYMBOL. |
| * Do the check to avoid writing to a const string. */ |
| if (*p != SPECIAL_VAR_SYMBOL) |
| *p = SPECIAL_VAR_SYMBOL; |
| arg = ++p; |
| } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */ |
| |
| if (*arg) { |
| /* handle trailing string */ |
| if (output->ended_in_ifs) { |
| o_addchr(output, '\0'); |
| n = o_save_ptr(output, n); |
| } |
| debug_print_list("expand_vars_to_list[a]", output, n); |
| /* this part is literal, and it was already pre-quoted |
| * if needed (much earlier), do not use o_addQstr here! |
| */ |
| o_addstr(output, arg); |
| debug_print_list("expand_vars_to_list[b]", output, n); |
| } else |
| if (output->length == o_get_last_ptr(output, n) /* expansion is empty */ |
| && !(cant_be_null & 0x80) /* and all vars were not quoted */ |
| && !output->has_quoted_part |
| ) { |
| n--; |
| /* allow to reuse list[n] later without re-growth */ |
| output->has_empty_slot = 1; |
| } |
| |
| return n; |
| } |
| |
| static char **expand_variables(char **argv, unsigned expflags) |
| { |
| int n; |
| char **list; |
| o_string output = NULL_O_STRING; |
| |
| output.o_expflags = expflags; |
| |
| n = 0; |
| for (;;) { |
| /* go to next list[n] */ |
| output.ended_in_ifs = 0; |
| n = o_save_ptr(&output, n); |
| |
| if (!*argv) |
| break; |
| |
| /* expand argv[i] */ |
| n = expand_vars_to_list(&output, n, *argv++); |
| /* if (!output->has_empty_slot) -- need this?? */ |
| o_addchr(&output, '\0'); |
| } |
| debug_print_list("expand_variables", &output, n); |
| |
| /* output.data (malloced in one block) gets returned in "list" */ |
| list = o_finalize_list(&output, n); |
| debug_print_strings("expand_variables[1]", list); |
| return list; |
| } |
| |
| static char **expand_strvec_to_strvec(char **argv) |
| { |
| return expand_variables(argv, EXP_FLAG_GLOB | EXP_FLAG_ESC_GLOB_CHARS); |
| } |
| |
| #if defined(CMD_SINGLEWORD_NOGLOB) || defined(CMD_TEST2_SINGLEWORD_NOGLOB) |
| static char **expand_strvec_to_strvec_singleword_noglob(char **argv) |
| { |
| return expand_variables(argv, EXP_FLAG_SINGLEWORD); |
| } |
| #endif |
| |
| /* Used for expansion of right hand of assignments, |
| * $((...)), heredocs, variable expansion parts. |
| * |
| * NB: should NOT do globbing! |
| * "export v=/bin/c*; env | grep ^v=" outputs "v=/bin/c*" |
| */ |
| static char *expand_string_to_string(const char *str, int EXP_flags, int do_unbackslash) |
| { |
| #if !BASH_PATTERN_SUBST && !ENABLE_HUSH_CASE |
| const int do_unbackslash = 1; |
| const int EXP_flags = EXP_FLAG_ESC_GLOB_CHARS; |
| #endif |
| char *argv[2], **list; |
| |
| debug_printf_expand("string_to_string<='%s'\n", str); |
| /* This is generally an optimization, but it also |
| * handles "", which otherwise trips over !list[0] check below. |
| * (is this ever happens that we actually get str="" here?) |
| */ |
| if (!strchr(str, SPECIAL_VAR_SYMBOL) && !strchr(str, '\\')) { |
| //TODO: Can use on strings with \ too, just unbackslash() them? |
| debug_printf_expand("string_to_string(fast)=>'%s'\n", str); |
| return xstrdup(str); |
| } |
| |
| argv[0] = (char*)str; |
| argv[1] = NULL; |
| list = expand_variables(argv, EXP_flags | EXP_FLAG_SINGLEWORD); |
| if (!list[0]) { |
| /* Example where it happens: |
| * x=; echo ${x:-"$@"} |
| */ |
| ((char*)list)[0] = '\0'; |
| } else { |
| if (HUSH_DEBUG) |
| if (list[1]) |
| bb_simple_error_msg_and_die("BUG in varexp2"); |
| /* actually, just move string 2*sizeof(char*) bytes back */ |
| overlapping_strcpy((char*)list, list[0]); |
| if (do_unbackslash) |
| unbackslash((char*)list); |
| } |
| debug_printf_expand("string_to_string=>'%s'\n", (char*)list); |
| return (char*)list; |
| } |
| |
| #if 0 |
| static char* expand_strvec_to_string(char **argv) |
| { |
| char **list; |
| |
| list = expand_variables(argv, EXP_FLAG_SINGLEWORD); |
| /* Convert all NULs to spaces */ |
| if (list[0]) { |
| int n = 1; |
| while (list[n]) { |
| if (HUSH_DEBUG) |
| if (list[n-1] + strlen(list[n-1]) + 1 != list[n]) |
| bb_error_msg_and_die("BUG in varexp3"); |
| /* bash uses ' ' regardless of $IFS contents */ |
| list[n][-1] = ' '; |
| n++; |
| } |
| } |
| overlapping_strcpy((char*)list, list[0] ? list[0] : ""); |
| debug_printf_expand("strvec_to_string='%s'\n", (char*)list); |
| return (char*)list; |
| } |
| #endif |
| |
| static char **expand_assignments(char **argv, int count) |
| { |
| int i; |
| char **p; |
| |
| G.expanded_assignments = p = NULL; |
| /* Expand assignments into one string each */ |
| for (i = 0; i < count; i++) { |
| p = add_string_to_strings(p, |
| expand_string_to_string(argv[i], |
| EXP_FLAG_ESC_GLOB_CHARS, |
| /*unbackslash:*/ 1 |
| ) |
| ); |
| G.expanded_assignments = p; |
| } |
| G.expanded_assignments = NULL; |
| return p; |
| } |
| |
| |
| static void switch_off_special_sigs(unsigned mask) |
| { |
| unsigned sig = 0; |
| while ((mask >>= 1) != 0) { |
| sig++; |
| if (!(mask & 1)) |
| continue; |
| #if ENABLE_HUSH_TRAP |
| if (G_traps) { |
| if (G_traps[sig] && !G_traps[sig][0]) |
| /* trap is '', has to remain SIG_IGN */ |
| continue; |
| free(G_traps[sig]); |
| G_traps[sig] = NULL; |
| } |
| #endif |
| /* We are here only if no trap or trap was not '' */ |
| install_sighandler(sig, SIG_DFL); |
| } |
| } |
| |
| #if BB_MMU |
| /* never called */ |
| void re_execute_shell(char ***to_free, const char *s, |
| char *g_argv0, char **g_argv, |
| char **builtin_argv) NORETURN; |
| |
| static void reset_traps_to_defaults(void) |
| { |
| /* This function is always called in a child shell |
| * after fork (not vfork, NOMMU doesn't use this function). |
| */ |
| IF_HUSH_TRAP(unsigned sig;) |
| unsigned mask; |
| |
| /* Child shells are not interactive. |
| * SIGTTIN/SIGTTOU/SIGTSTP should not have special handling. |
| * Testcase: (while :; do :; done) + ^Z should background. |
| * Same goes for SIGTERM, SIGHUP, SIGINT. |
| */ |
| mask = (G.special_sig_mask & SPECIAL_INTERACTIVE_SIGS) | G_fatal_sig_mask; |
| if (!G_traps && !mask) |
| return; /* already no traps and no special sigs */ |
| |
| /* Switch off special sigs */ |
| switch_off_special_sigs(mask); |
| # if ENABLE_HUSH_JOB |
| G_fatal_sig_mask = 0; |
| # endif |
| G.special_sig_mask &= ~SPECIAL_INTERACTIVE_SIGS; |
| /* SIGQUIT,SIGCHLD and maybe SPECIAL_JOBSTOP_SIGS |
| * remain set in G.special_sig_mask */ |
| |
| # if ENABLE_HUSH_TRAP |
| if (!G_traps) |
| return; |
| |
| /* Reset all sigs to default except ones with empty traps */ |
| for (sig = 0; sig < NSIG; sig++) { |
| if (!G_traps[sig]) |
| continue; /* no trap: nothing to do */ |
| if (!G_traps[sig][0]) |
| continue; /* empty trap: has to remain SIG_IGN */ |
| /* sig has non-empty trap, reset it: */ |
| free(G_traps[sig]); |
| G_traps[sig] = NULL; |
| /* There is no signal for trap 0 (EXIT) */ |
| if (sig == 0) |
| continue; |
| install_sighandler(sig, pick_sighandler(sig)); |
| } |
| # endif |
| } |
| |
| #else /* !BB_MMU */ |
| |
| static void re_execute_shell(char ***to_free, const char *s, |
| char *g_argv0, char **g_argv, |
| char **builtin_argv) NORETURN; |
| static void re_execute_shell(char ***to_free, const char *s, |
| char *g_argv0, char **g_argv, |
| char **builtin_argv) |
| { |
| # define NOMMU_HACK_FMT ("-$%x:%x:%x:%x:%x:%llx" IF_HUSH_LOOPS(":%x")) |
| /* delims + 2 * (number of bytes in printed hex numbers) */ |
| char param_buf[sizeof(NOMMU_HACK_FMT) + 2 * (sizeof(int)*6 + sizeof(long long)*1)]; |
| char *heredoc_argv[4]; |
| struct variable *cur; |
| # if ENABLE_HUSH_FUNCTIONS |
| struct function *funcp; |
| # endif |
| char **argv, **pp; |
| unsigned cnt; |
| unsigned long long empty_trap_mask; |
| |
| if (!g_argv0) { /* heredoc */ |
| argv = heredoc_argv; |
| argv[0] = (char *) G.argv0_for_re_execing; |
| argv[1] = (char *) "-<"; |
| argv[2] = (char *) s; |
| argv[3] = NULL; |
| pp = &argv[3]; /* used as pointer to empty environment */ |
| goto do_exec; |
| } |
| |
| cnt = 0; |
| pp = builtin_argv; |
| if (pp) while (*pp++) |
| cnt++; |
| |
| empty_trap_mask = 0; |
| if (G_traps) { |
| int sig; |
| for (sig = 1; sig < NSIG; sig++) { |
| if (G_traps[sig] && !G_traps[sig][0]) |
| empty_trap_mask |= 1LL << sig; |
| } |
| } |
| |
| sprintf(param_buf, NOMMU_HACK_FMT |
| , (unsigned) G.root_pid |
| , (unsigned) G.root_ppid |
| , (unsigned) G.last_bg_pid |
| , (unsigned) G.last_exitcode |
| , cnt |
| , empty_trap_mask |
| IF_HUSH_LOOPS(, G.depth_of_loop) |
| ); |
| # undef NOMMU_HACK_FMT |
| /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<etc...> <vars...> <funcs...> |
| * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL |
| */ |
| cnt += 6; |
| for (cur = G.top_var; cur; cur = cur->next) { |
| if (!cur->flg_export || cur->flg_read_only) |
| cnt += 2; |
| } |
| # if ENABLE_HUSH_FUNCTIONS |
| for (funcp = G.top_func; funcp; funcp = funcp->next) |
| cnt += 3; |
| # endif |
| pp = g_argv; |
| while (*pp++) |
| cnt++; |
| *to_free = argv = pp = xzalloc(sizeof(argv[0]) * cnt); |
| *pp++ = (char *) G.argv0_for_re_execing; |
| *pp++ = param_buf; |
| for (cur = G.top_var; cur; cur = cur->next) { |
| if (strcmp(cur->varstr, hush_version_str) == 0) |
| continue; |
| if (cur->flg_read_only) { |
| *pp++ = (char *) "-R"; |
| *pp++ = cur->varstr; |
| } else if (!cur->flg_export) { |
| *pp++ = (char *) "-V"; |
| *pp++ = cur->varstr; |
| } |
| } |
| # if ENABLE_HUSH_FUNCTIONS |
| for (funcp = G.top_func; funcp; funcp = funcp->next) { |
| *pp++ = (char *) "-F"; |
| *pp++ = funcp->name; |
| *pp++ = funcp->body_as_string; |
| } |
| # endif |
| /* We can pass activated traps here. Say, -Tnn:trap_string |
| * |
| * However, POSIX says that subshells reset signals with traps |
| * to SIG_DFL. |
| * I tested bash-3.2 and it not only does that with true subshells |
| * of the form ( list ), but with any forked children shells. |
| * I set trap "echo W" WINCH; and then tried: |
| * |
| * { echo 1; sleep 20; echo 2; } & |
| * while true; do echo 1; sleep 20; echo 2; break; done & |
| * true | { echo 1; sleep 20; echo 2; } | cat |
| * |
| * In all these cases sending SIGWINCH to the child shell |
| * did not run the trap. If I add trap "echo V" WINCH; |
| * _inside_ group (just before echo 1), it works. |
| * |
| * I conclude it means we don't need to pass active traps here. |
| */ |
| *pp++ = (char *) "-c"; |
| *pp++ = (char *) s; |
| if (builtin_argv) { |
| while (*++builtin_argv) |
| *pp++ = *builtin_argv; |
| *pp++ = (char *) ""; |
| } |
| *pp++ = g_argv0; |
| while (*g_argv) |
| *pp++ = *g_argv++; |
| /* *pp = NULL; - is already there */ |
| pp = environ; |
| |
| do_exec: |
| debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s); |
| /* Don't propagate SIG_IGN to the child */ |
| if (SPECIAL_JOBSTOP_SIGS != 0) |
| switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS); |
| execve(bb_busybox_exec_path, argv, pp); |
| /* Fallback. Useful for init=/bin/hush usage etc */ |
| if (argv[0][0] == '/') |
| execve(argv[0], argv, pp); |
| xfunc_error_retval = 127; |
| bb_simple_error_msg_and_die("can't re-execute the shell"); |
| } |
| #endif /* !BB_MMU */ |
| |
| |
| static int run_and_free_list(struct pipe *pi); |
| |
| /* Executing from string: eval, sh -c '...' |
| * or from file: /etc/profile, . file, sh <script>, sh (intereactive) |
| * end_trigger controls how often we stop parsing |
| * NUL: parse all, execute, return |
| * ';': parse till ';' or newline, execute, repeat till EOF |
| */ |
| static void parse_and_run_stream(struct in_str *inp, int end_trigger) |
| { |
| /* Why we need empty flag? |
| * An obscure corner case "false; ``; echo $?": |
| * empty command in `` should still set $? to 0. |
| * But we can't just set $? to 0 at the start, |
| * this breaks "false; echo `echo $?`" case. |
| */ |
| bool empty = 1; |
| while (1) { |
| struct pipe *pipe_list; |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| if (end_trigger == ';') { |
| G.promptmode = 0; /* PS1 */ |
| debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode); |
| } |
| #endif |
| pipe_list = parse_stream(NULL, NULL, inp, end_trigger); |
| if (!pipe_list || pipe_list == ERR_PTR) { /* EOF/error */ |
| /* If we are in "big" script |
| * (not in `cmd` or something similar)... |
| */ |
| if (pipe_list == ERR_PTR && end_trigger == ';') { |
| /* Discard cached input (rest of line) */ |
| int ch = inp->last_char; |
| while (ch != EOF && ch != '\n') { |
| //bb_error_msg("Discarded:'%c'", ch); |
| ch = i_getch(inp); |
| } |
| /* Force prompt */ |
| inp->p = NULL; |
| /* This stream isn't empty */ |
| empty = 0; |
| continue; |
| } |
| if (!pipe_list && empty) |
| G.last_exitcode = 0; |
| break; |
| } |
| debug_print_tree(pipe_list, 0); |
| debug_printf_exec("parse_and_run_stream: run_and_free_list\n"); |
| run_and_free_list(pipe_list); |
| empty = 0; |
| if (G_flag_return_in_progress == 1) |
| break; |
| } |
| } |
| |
| static void parse_and_run_string(const char *s) |
| { |
| struct in_str input; |
| IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) |
| |
| setup_string_in_str(&input, s); |
| parse_and_run_stream(&input, '\0'); |
| IF_HUSH_LINENO_VAR(G.parse_lineno = sv;) |
| } |
| |
| static void parse_and_run_file(HFILE *fp) |
| { |
| struct in_str input; |
| IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) |
| |
| IF_HUSH_LINENO_VAR(G.parse_lineno = 1;) |
| setup_file_in_str(&input, fp); |
| parse_and_run_stream(&input, ';'); |
| IF_HUSH_LINENO_VAR(G.parse_lineno = sv;) |
| } |
| |
| #if ENABLE_HUSH_TICK |
| static int generate_stream_from_string(const char *s, pid_t *pid_p) |
| { |
| pid_t pid; |
| int channel[2]; |
| # if !BB_MMU |
| char **to_free = NULL; |
| # endif |
| |
| xpipe(channel); |
| pid = BB_MMU ? xfork() : xvfork(); |
| if (pid == 0) { /* child */ |
| disable_restore_tty_pgrp_on_exit(); |
| /* Process substitution is not considered to be usual |
| * 'command execution'. |
| * SUSv3 says ctrl-Z should be ignored, ctrl-C should not. |
| */ |
| bb_signals(0 |
| + (1 << SIGTSTP) |
| + (1 << SIGTTIN) |
| + (1 << SIGTTOU) |
| , SIG_IGN); |
| close(channel[0]); /* NB: close _first_, then move fd! */ |
| xmove_fd(channel[1], 1); |
| # if ENABLE_HUSH_TRAP |
| /* Awful hack for `trap` or $(trap). |
| * |
| * http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html |
| * contains an example where "trap" is executed in a subshell: |
| * |
| * save_traps=$(trap) |
| * ... |
| * eval "$save_traps" |
| * |
| * Standard does not say that "trap" in subshell shall print |
| * parent shell's traps. It only says that its output |
| * must have suitable form, but then, in the above example |
| * (which is not supposed to be normative), it implies that. |
| * |
| * bash (and probably other shell) does implement it |
| * (traps are reset to defaults, but "trap" still shows them), |
| * but as a result, "trap" logic is hopelessly messed up: |
| * |
| * # trap |
| * trap -- 'echo Ho' SIGWINCH <--- we have a handler |
| * # (trap) <--- trap is in subshell - no output (correct, traps are reset) |
| * # true | trap <--- trap is in subshell - no output (ditto) |
| * # echo `true | trap` <--- in subshell - output (but traps are reset!) |
| * trap -- 'echo Ho' SIGWINCH |
| * # echo `(trap)` <--- in subshell in subshell - output |
| * trap -- 'echo Ho' SIGWINCH |
| * # echo `true | (trap)` <--- in subshell in subshell in subshell - output! |
| * trap -- 'echo Ho' SIGWINCH |
| * |
| * The rules when to forget and when to not forget traps |
| * get really complex and nonsensical. |
| * |
| * Our solution: ONLY bare $(trap) or `trap` is special. |
| */ |
| s = skip_whitespace(s); |
| if (is_prefixed_with(s, "trap") |
| && skip_whitespace(s + 4)[0] == '\0' |
| ) { |
| static const char *const argv[] = { NULL, NULL }; |
| builtin_trap((char**)argv); |
| fflush_all(); /* important */ |
| _exit(0); |
| } |
| # endif |
| # if BB_MMU |
| /* Prevent it from trying to handle ctrl-z etc */ |
| IF_HUSH_JOB(G.run_list_level = 1;) |
| CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */ |
| reset_traps_to_defaults(); |
| IF_HUSH_MODE_X(G.x_mode_depth++;) |
| //bb_error_msg("%s: ++x_mode_depth=%d", __func__, G.x_mode_depth); |
| parse_and_run_string(s); |
| _exit(G.last_exitcode); |
| # else |
| /* We re-execute after vfork on NOMMU. This makes this script safe: |
| * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG |
| * huge=`cat BIG` # was blocking here forever |
| * echo OK |
| */ |
| re_execute_shell(&to_free, |
| s, |
| G.global_argv[0], |
| G.global_argv + 1, |
| NULL); |
| # endif |
| } |
| |
| /* parent */ |
| *pid_p = pid; |
| # if ENABLE_HUSH_FAST |
| G.count_SIGCHLD++; |
| //bb_error_msg("[%d] fork in generate_stream_from_string:" |
| // " G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", |
| // getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| # endif |
| enable_restore_tty_pgrp_on_exit(); |
| # if !BB_MMU |
| free(to_free); |
| # endif |
| close(channel[1]); |
| return channel[0]; |
| } |
| |
| /* Return code is exit status of the process that is run. */ |
| static int process_command_subs(o_string *dest, const char *s) |
| { |
| FILE *fp; |
| pid_t pid; |
| int status, ch, eol_cnt; |
| |
| fp = xfdopen_for_read(generate_stream_from_string(s, &pid)); |
| |
| /* Now send results of command back into original context */ |
| eol_cnt = 0; |
| while ((ch = getc(fp)) != EOF) { |
| if (ch == '\0') |
| continue; |
| if (ch == '\n') { |
| eol_cnt++; |
| continue; |
| } |
| while (eol_cnt) { |
| o_addchr(dest, '\n'); |
| eol_cnt--; |
| } |
| o_addQchr(dest, ch); |
| } |
| |
| debug_printf("done reading from `cmd` pipe, closing it\n"); |
| fclose(fp); |
| /* We need to extract exitcode. Test case |
| * "true; echo `sleep 1; false` $?" |
| * should print 1 */ |
| safe_waitpid(pid, &status, 0); |
| debug_printf("child exited. returning its exitcode:%d\n", WEXITSTATUS(status)); |
| return WEXITSTATUS(status); |
| } |
| #endif /* ENABLE_HUSH_TICK */ |
| |
| |
| static void setup_heredoc(struct redir_struct *redir) |
| { |
| struct fd_pair pair; |
| pid_t pid; |
| int len, written; |
| /* the _body_ of heredoc (misleading field name) */ |
| const char *heredoc = redir->rd_filename; |
| char *expanded; |
| #if !BB_MMU |
| char **to_free; |
| #endif |
| |
| expanded = NULL; |
| if (!(redir->rd_dup & HEREDOC_QUOTED)) { |
| expanded = encode_then_expand_string(heredoc); |
| if (expanded) |
| heredoc = expanded; |
| } |
| len = strlen(heredoc); |
| |
| close(redir->rd_fd); /* often saves dup2+close in xmove_fd */ |
| xpiped_pair(pair); |
| xmove_fd(pair.rd, redir->rd_fd); |
| |
| /* Try writing without forking. Newer kernels have |
| * dynamically growing pipes. Must use non-blocking write! */ |
| ndelay_on(pair.wr); |
| while (1) { |
| written = write(pair.wr, heredoc, len); |
| if (written <= 0) |
| break; |
| len -= written; |
| if (len == 0) { |
| close(pair.wr); |
| free(expanded); |
| return; |
| } |
| heredoc += written; |
| } |
| ndelay_off(pair.wr); |
| |
| /* Okay, pipe buffer was not big enough */ |
| /* Note: we must not create a stray child (bastard? :) |
| * for the unsuspecting parent process. Child creates a grandchild |
| * and exits before parent execs the process which consumes heredoc |
| * (that exec happens after we return from this function) */ |
| #if !BB_MMU |
| to_free = NULL; |
| #endif |
| pid = xvfork(); |
| if (pid == 0) { |
| /* child */ |
| disable_restore_tty_pgrp_on_exit(); |
| pid = BB_MMU ? xfork() : xvfork(); |
| if (pid != 0) |
| _exit(0); |
| /* grandchild */ |
| close(redir->rd_fd); /* read side of the pipe */ |
| #if BB_MMU |
| full_write(pair.wr, heredoc, len); /* may loop or block */ |
| _exit(0); |
| #else |
| /* Delegate blocking writes to another process */ |
| xmove_fd(pair.wr, STDOUT_FILENO); |
| re_execute_shell(&to_free, heredoc, NULL, NULL, NULL); |
| #endif |
| } |
| /* parent */ |
| #if ENABLE_HUSH_FAST |
| G.count_SIGCHLD++; |
| //bb_error_msg("[%d] fork in setup_heredoc: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| #endif |
| enable_restore_tty_pgrp_on_exit(); |
| #if !BB_MMU |
| free(to_free); |
| #endif |
| close(pair.wr); |
| free(expanded); |
| wait(NULL); /* wait till child has died */ |
| } |
| |
| struct squirrel { |
| int orig_fd; |
| int moved_to; |
| /* moved_to = n: fd was moved to n; restore back to orig_fd after redir */ |
| /* moved_to = -1: fd was opened by redirect; close orig_fd after redir */ |
| }; |
| |
| static struct squirrel *append_squirrel(struct squirrel *sq, int i, int orig, int moved) |
| { |
| sq = xrealloc(sq, (i + 2) * sizeof(sq[0])); |
| sq[i].orig_fd = orig; |
| sq[i].moved_to = moved; |
| sq[i+1].orig_fd = -1; /* end marker */ |
| return sq; |
| } |
| |
| static struct squirrel *add_squirrel(struct squirrel *sq, int fd, int avoid_fd) |
| { |
| int moved_to; |
| int i; |
| |
| i = 0; |
| if (sq) for (; sq[i].orig_fd >= 0; i++) { |
| /* If we collide with an already moved fd... */ |
| if (fd == sq[i].moved_to) { |
| sq[i].moved_to = dup_CLOEXEC(sq[i].moved_to, avoid_fd); |
| debug_printf_redir("redirect_fd %d: already busy, moving to %d\n", fd, sq[i].moved_to); |
| if (sq[i].moved_to < 0) /* what? */ |
| xfunc_die(); |
| return sq; |
| } |
| if (fd == sq[i].orig_fd) { |
| /* Example: echo Hello >/dev/null 1>&2 */ |
| debug_printf_redir("redirect_fd %d: already moved\n", fd); |
| return sq; |
| } |
| } |
| |
| /* If this fd is open, we move and remember it; if it's closed, moved_to = -1 */ |
| moved_to = dup_CLOEXEC(fd, avoid_fd); |
| debug_printf_redir("redirect_fd %d: previous fd is moved to %d (-1 if it was closed)\n", fd, moved_to); |
| if (moved_to < 0 && errno != EBADF) |
| xfunc_die(); |
| return append_squirrel(sq, i, fd, moved_to); |
| } |
| |
| static struct squirrel *add_squirrel_closed(struct squirrel *sq, int fd) |
| { |
| int i; |
| |
| i = 0; |
| if (sq) for (; sq[i].orig_fd >= 0; i++) { |
| /* If we collide with an already moved fd... */ |
| if (fd == sq[i].orig_fd) { |
| /* Examples: |
| * "echo 3>FILE 3>&- 3>FILE" |
| * "echo 3>&- 3>FILE" |
| * No need for last redirect to insert |
| * another "need to close 3" indicator. |
| */ |
| debug_printf_redir("redirect_fd %d: already moved or closed\n", fd); |
| return sq; |
| } |
| } |
| |
| debug_printf_redir("redirect_fd %d: previous fd was closed\n", fd); |
| return append_squirrel(sq, i, fd, -1); |
| } |
| |
| /* fd: redirect wants this fd to be used (e.g. 3>file). |
| * Move all conflicting internally used fds, |
| * and remember them so that we can restore them later. |
| */ |
| static int save_fd_on_redirect(int fd, int avoid_fd, struct squirrel **sqp) |
| { |
| if (avoid_fd < 9) /* the important case here is that it can be -1 */ |
| avoid_fd = 9; |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| if (fd != 0 /* don't trigger for G_interactive_fd == 0 (that's "not interactive" flag) */ |
| && fd == G_interactive_fd |
| ) { |
| /* Testcase: "ls -l /proc/$$/fd 255>&-" should work */ |
| G_interactive_fd = xdup_CLOEXEC_and_close(G_interactive_fd, avoid_fd); |
| debug_printf_redir("redirect_fd %d: matches interactive_fd, moving it to %d\n", fd, G_interactive_fd); |
| return 1; /* "we closed fd" */ |
| } |
| #endif |
| /* Are we called from setup_redirects(squirrel==NULL) |
| * in redirect in a [v]forked child? |
| */ |
| if (sqp == NULL) { |
| /* No need to move script fds. |
| * For NOMMU case, it's actively wrong: we'd change ->fd |
| * fields in memory for the parent, but parent's fds |
| * aren't moved, it would use wrong fd! |
| * Reproducer: "cmd 3>FILE" in script. |
| * If we would call move_HFILEs_on_redirect(), child would: |
| * fcntl64(3, F_DUPFD_CLOEXEC, 10) = 10 |
| * close(3) = 0 |
| * and change ->fd to 10 if fd#3 is a script fd. WRONG. |
| */ |
| //bb_error_msg("sqp == NULL: [v]forked child"); |
| return 0; |
| } |
| |
| /* If this one of script's fds? */ |
| if (move_HFILEs_on_redirect(fd, avoid_fd)) |
| return 1; /* yes. "we closed fd" (actually moved it) */ |
| |
| /* Are we called for "exec 3>FILE"? Came through |
| * redirect_and_varexp_helper(squirrel=ERR_PTR) -> setup_redirects(ERR_PTR) |
| * This case used to fail for this script: |
| * exec 3>FILE |
| * echo Ok |
| * ...100000 more lines... |
| * echo Ok |
| * as follows: |
| * read(3, "exec 3>FILE\necho Ok\necho Ok"..., 1024) = 1024 |
| * open("FILE", O_WRONLY|O_CREAT|O_TRUNC|O_LARGEFILE, 0666) = 4 |
| * dup2(4, 3) = 3 |
| * ^^^^^^^^ oops, we lost fd#3 opened to our script! |
| * close(4) = 0 |
| * write(1, "Ok\n", 3) = 3 |
| * ... = 3 |
| * write(1, "Ok\n", 3) = 3 |
| * read(3, 0x94fbc08, 1024) = -1 EBADF (Bad file descriptor) |
| * ^^^^^^^^ oops, wrong fd!!! |
| * With this case separate from sqp == NULL and *after* move_HFILEs, |
| * it now works: |
| */ |
| if (sqp == ERR_PTR) { |
| /* Don't preserve redirected fds: exec is _meant_ to change these */ |
| //bb_error_msg("sqp == ERR_PTR: exec >FILE"); |
| return 0; |
| } |
| |
| /* Check whether it collides with any open fds (e.g. stdio), save fds as needed */ |
| *sqp = add_squirrel(*sqp, fd, avoid_fd); |
| return 0; /* "we did not close fd" */ |
| } |
| |
| static void restore_redirects(struct squirrel *sq) |
| { |
| if (sq) { |
| int i; |
| for (i = 0; sq[i].orig_fd >= 0; i++) { |
| if (sq[i].moved_to >= 0) { |
| /* We simply die on error */ |
| debug_printf_redir("restoring redirected fd from %d to %d\n", sq[i].moved_to, sq[i].orig_fd); |
| xmove_fd(sq[i].moved_to, sq[i].orig_fd); |
| } else { |
| /* cmd1 9>FILE; cmd2_should_see_fd9_closed */ |
| debug_printf_redir("restoring redirected fd %d: closing it\n", sq[i].orig_fd); |
| close(sq[i].orig_fd); |
| } |
| } |
| free(sq); |
| } |
| if (G.HFILE_stdin |
| && G.HFILE_stdin->fd > STDIN_FILENO |
| /* we compare > STDIN, not == STDIN, since hfgetc() |
| * closes fd and sets ->fd to -1 if EOF is reached. |
| * Testcase: echo 'pwd' | hush |
| */ |
| ) { |
| /* Testcase: interactive "read r <FILE; echo $r; read r; echo $r". |
| * Redirect moves ->fd to e.g. 10, |
| * and it is not restored above (we do not restore script fds |
| * after redirects, we just use new, "moved" fds). |
| * However for stdin, get_user_input() -> read_line_input(), |
| * and read builtin, depend on fd == STDIN_FILENO. |
| */ |
| debug_printf_redir("restoring %d to stdin\n", G.HFILE_stdin->fd); |
| xmove_fd(G.HFILE_stdin->fd, STDIN_FILENO); |
| G.HFILE_stdin->fd = STDIN_FILENO; |
| } |
| |
| /* If moved, G_interactive_fd stays on new fd, not restoring it */ |
| } |
| |
| #if ENABLE_FEATURE_SH_STANDALONE && BB_MMU |
| static void close_saved_fds_and_FILE_fds(void) |
| { |
| if (G_interactive_fd) |
| close(G_interactive_fd); |
| close_all_HFILE_list(); |
| } |
| #endif |
| |
| static int internally_opened_fd(int fd, struct squirrel *sq) |
| { |
| int i; |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| if (fd == G_interactive_fd) |
| return 1; |
| #endif |
| /* If this one of script's fds? */ |
| if (fd_in_HFILEs(fd)) |
| return 1; |
| |
| if (sq) for (i = 0; sq[i].orig_fd >= 0; i++) { |
| if (fd == sq[i].moved_to) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* squirrel != NULL means we squirrel away copies of stdin, stdout, |
| * and stderr if they are redirected. */ |
| static int setup_redirects(struct command *prog, struct squirrel **sqp) |
| { |
| struct redir_struct *redir; |
| |
| for (redir = prog->redirects; redir; redir = redir->next) { |
| int newfd; |
| int closed; |
| |
| if (redir->rd_type == REDIRECT_HEREDOC2) { |
| /* "rd_fd<<HERE" case */ |
| save_fd_on_redirect(redir->rd_fd, /*avoid:*/ 0, sqp); |
| /* for REDIRECT_HEREDOC2, rd_filename holds _contents_ |
| * of the heredoc */ |
| debug_printf_redir("set heredoc '%s'\n", |
| redir->rd_filename); |
| setup_heredoc(redir); |
| continue; |
| } |
| |
| if (redir->rd_dup == REDIRFD_TO_FILE) { |
| /* "rd_fd<*>file" case (<*> is <,>,>>,<>) */ |
| char *p; |
| int mode; |
| |
| if (redir->rd_filename == NULL) { |
| /* Examples: |
| * "cmd >" (no filename) |
| * "cmd > <file" (2nd redirect starts too early) |
| */ |
| syntax_error("invalid redirect"); |
| continue; |
| } |
| mode = redir_table[redir->rd_type].mode; |
| p = expand_string_to_string(redir->rd_filename, |
| EXP_FLAG_ESC_GLOB_CHARS, /*unbackslash:*/ 1); |
| newfd = open_or_warn(p, mode); |
| free(p); |
| if (newfd < 0) { |
| /* Error message from open_or_warn can be lost |
| * if stderr has been redirected, but bash |
| * and ash both lose it as well |
| * (though zsh doesn't!) |
| */ |
| return 1; |
| } |
| if (newfd == redir->rd_fd && sqp) { |
| /* open() gave us precisely the fd we wanted. |
| * This means that this fd was not busy |
| * (not opened to anywhere). |
| * Remember to close it on restore: |
| */ |
| *sqp = add_squirrel_closed(*sqp, newfd); |
| debug_printf_redir("redir to previously closed fd %d\n", newfd); |
| } |
| } else { |
| /* "rd_fd>&rd_dup" or "rd_fd>&-" case */ |
| newfd = redir->rd_dup; |
| } |
| |
| if (newfd == redir->rd_fd) |
| continue; |
| |
| /* if "N>FILE": move newfd to redir->rd_fd */ |
| /* if "N>&M": dup newfd to redir->rd_fd */ |
| /* if "N>&-": close redir->rd_fd (newfd is REDIRFD_CLOSE) */ |
| |
| closed = save_fd_on_redirect(redir->rd_fd, /*avoid:*/ newfd, sqp); |
| if (newfd == REDIRFD_CLOSE) { |
| /* "N>&-" means "close me" */ |
| if (!closed) { |
| /* ^^^ optimization: saving may already |
| * have closed it. If not... */ |
| close(redir->rd_fd); |
| } |
| /* Sometimes we do another close on restore, getting EBADF. |
| * Consider "echo 3>FILE 3>&-" |
| * first redirect remembers "need to close 3", |
| * and second redirect closes 3! Restore code then closes 3 again. |
| */ |
| } else { |
| /* if newfd is a script fd or saved fd, simulate EBADF */ |
| if (internally_opened_fd(newfd, sqp && sqp != ERR_PTR ? *sqp : NULL)) { |
| //errno = EBADF; |
| //bb_perror_msg_and_die("can't duplicate file descriptor"); |
| newfd = -1; /* same effect as code above */ |
| } |
| xdup2(newfd, redir->rd_fd); |
| if (redir->rd_dup == REDIRFD_TO_FILE) |
| /* "rd_fd > FILE" */ |
| close(newfd); |
| /* else: "rd_fd > rd_dup" */ |
| } |
| } |
| return 0; |
| } |
| |
| static char *find_in_path(const char *arg) |
| { |
| char *ret = NULL; |
| const char *PATH = get_local_var_value("PATH"); |
| |
| if (!PATH) |
| return NULL; |
| |
| while (1) { |
| const char *end = strchrnul(PATH, ':'); |
| int sz = end - PATH; /* must be int! */ |
| |
| free(ret); |
| if (sz != 0) { |
| ret = xasprintf("%.*s/%s", sz, PATH, arg); |
| } else { |
| /* We have xxx::yyyy in $PATH, |
| * it means "use current dir" */ |
| ret = xstrdup(arg); |
| } |
| if (access(ret, F_OK) == 0) |
| break; |
| |
| if (*end == '\0') { |
| free(ret); |
| return NULL; |
| } |
| PATH = end + 1; |
| } |
| |
| return ret; |
| } |
| |
| static const struct built_in_command *find_builtin_helper(const char *name, |
| const struct built_in_command *x, |
| const struct built_in_command *end) |
| { |
| while (x != end) { |
| if (strcmp(name, x->b_cmd) != 0) { |
| x++; |
| continue; |
| } |
| debug_printf_exec("found builtin '%s'\n", name); |
| return x; |
| } |
| return NULL; |
| } |
| static const struct built_in_command *find_builtin1(const char *name) |
| { |
| return find_builtin_helper(name, bltins1, &bltins1[ARRAY_SIZE(bltins1)]); |
| } |
| static const struct built_in_command *find_builtin(const char *name) |
| { |
| const struct built_in_command *x = find_builtin1(name); |
| if (x) |
| return x; |
| return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]); |
| } |
| |
| #if ENABLE_HUSH_JOB && EDITING_HAS_get_exe_name |
| static const char * FAST_FUNC get_builtin_name(int i) |
| { |
| if (/*i >= 0 && */ i < ARRAY_SIZE(bltins1)) { |
| return bltins1[i].b_cmd; |
| } |
| i -= ARRAY_SIZE(bltins1); |
| if (i < ARRAY_SIZE(bltins2)) { |
| return bltins2[i].b_cmd; |
| } |
| return NULL; |
| } |
| #endif |
| |
| static void remove_nested_vars(void) |
| { |
| struct variable *cur; |
| struct variable **cur_pp; |
| |
| cur_pp = &G.top_var; |
| while ((cur = *cur_pp) != NULL) { |
| if (cur->var_nest_level <= G.var_nest_level) { |
| cur_pp = &cur->next; |
| continue; |
| } |
| /* Unexport */ |
| if (cur->flg_export) { |
| debug_printf_env("unexporting nested '%s'/%u\n", cur->varstr, cur->var_nest_level); |
| bb_unsetenv(cur->varstr); |
| } |
| /* Remove from global list */ |
| *cur_pp = cur->next; |
| /* Free */ |
| if (!cur->max_len) { |
| debug_printf_env("freeing nested '%s'/%u\n", cur->varstr, cur->var_nest_level); |
| free(cur->varstr); |
| } |
| free(cur); |
| } |
| } |
| |
| static void enter_var_nest_level(void) |
| { |
| G.var_nest_level++; |
| debug_printf_env("var_nest_level++ %u\n", G.var_nest_level); |
| |
| /* Try: f() { echo -n .; f; }; f |
| * struct variable::var_nest_level is uint16_t, |
| * thus limiting recursion to < 2^16. |
| * In any case, with 8 Mbyte stack SEGV happens |
| * not too long after 2^16 recursions anyway. |
| */ |
| if (G.var_nest_level > 0xff00) |
| bb_error_msg_and_die("fatal recursion (depth %u)", G.var_nest_level); |
| } |
| |
| static void leave_var_nest_level(void) |
| { |
| G.var_nest_level--; |
| debug_printf_env("var_nest_level-- %u\n", G.var_nest_level); |
| if (HUSH_DEBUG && (int)G.var_nest_level < 0) |
| bb_simple_error_msg_and_die("BUG: nesting underflow"); |
| |
| remove_nested_vars(); |
| } |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| static struct function **find_function_slot(const char *name) |
| { |
| struct function *funcp; |
| struct function **funcpp = &G.top_func; |
| |
| while ((funcp = *funcpp) != NULL) { |
| if (strcmp(name, funcp->name) == 0) { |
| debug_printf_exec("found function '%s'\n", name); |
| break; |
| } |
| funcpp = &funcp->next; |
| } |
| return funcpp; |
| } |
| |
| static ALWAYS_INLINE const struct function *find_function(const char *name) |
| { |
| const struct function *funcp = *find_function_slot(name); |
| return funcp; |
| } |
| |
| /* Note: takes ownership on name ptr */ |
| static struct function *new_function(char *name) |
| { |
| struct function **funcpp = find_function_slot(name); |
| struct function *funcp = *funcpp; |
| |
| if (funcp != NULL) { |
| struct command *cmd = funcp->parent_cmd; |
| debug_printf_exec("func %p parent_cmd %p\n", funcp, cmd); |
| if (!cmd) { |
| debug_printf_exec("freeing & replacing function '%s'\n", funcp->name); |
| free(funcp->name); |
| /* Note: if !funcp->body, do not free body_as_string! |
| * This is a special case of "-F name body" function: |
| * body_as_string was not malloced! */ |
| if (funcp->body) { |
| free_pipe_list(funcp->body); |
| # if !BB_MMU |
| free(funcp->body_as_string); |
| # endif |
| } |
| } else { |
| debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp->name); |
| cmd->argv[0] = funcp->name; |
| cmd->group = funcp->body; |
| # if !BB_MMU |
| cmd->group_as_string = funcp->body_as_string; |
| # endif |
| } |
| } else { |
| debug_printf_exec("remembering new function '%s'\n", name); |
| funcp = *funcpp = xzalloc(sizeof(*funcp)); |
| /*funcp->next = NULL;*/ |
| } |
| |
| funcp->name = name; |
| return funcp; |
| } |
| |
| # if ENABLE_HUSH_UNSET |
| static void unset_func(const char *name) |
| { |
| struct function **funcpp = find_function_slot(name); |
| struct function *funcp = *funcpp; |
| |
| if (funcp != NULL) { |
| debug_printf_exec("freeing function '%s'\n", funcp->name); |
| *funcpp = funcp->next; |
| /* funcp is unlinked now, deleting it. |
| * Note: if !funcp->body, the function was created by |
| * "-F name body", do not free ->body_as_string |
| * and ->name as they were not malloced. */ |
| if (funcp->body) { |
| free_pipe_list(funcp->body); |
| free(funcp->name); |
| # if !BB_MMU |
| free(funcp->body_as_string); |
| # endif |
| } |
| free(funcp); |
| } |
| } |
| # endif |
| |
| # if BB_MMU |
| #define exec_function(to_free, funcp, argv) \ |
| exec_function(funcp, argv) |
| # endif |
| static void exec_function(char ***to_free, |
| const struct function *funcp, |
| char **argv) NORETURN; |
| static void exec_function(char ***to_free, |
| const struct function *funcp, |
| char **argv) |
| { |
| # if BB_MMU |
| int n; |
| |
| argv[0] = G.global_argv[0]; |
| G.global_argv = argv; |
| G.global_argc = n = 1 + string_array_len(argv + 1); |
| |
| // Example when we are here: "cmd | func" |
| // func will run with saved-redirect fds open. |
| // $ f() { echo /proc/self/fd/*; } |
| // $ true | f |
| // /proc/self/fd/0 /proc/self/fd/1 /proc/self/fd/2 /proc/self/fd/255 /proc/self/fd/3 |
| // stdio^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ G_interactive_fd^ DIR fd for glob |
| // Same in script: |
| // $ . ./SCRIPT |
| // /proc/self/fd/0 /proc/self/fd/1 /proc/self/fd/2 /proc/self/fd/255 /proc/self/fd/3 /proc/self/fd/4 |
| // stdio^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ G_interactive_fd^ opened ./SCRIPT DIR fd for glob |
| // They are CLOEXEC so external programs won't see them, but |
| // for "more correctness" we might want to close those extra fds here: |
| //? close_saved_fds_and_FILE_fds(); |
| |
| /* "we are in a function, ok to use return" */ |
| G_flag_return_in_progress = -1; |
| enter_var_nest_level(); |
| IF_HUSH_LOCAL(G.func_nest_level++;) |
| |
| /* On MMU, funcp->body is always non-NULL */ |
| n = run_list(funcp->body); |
| _exit(n); |
| # else |
| //? close_saved_fds_and_FILE_fds(); |
| |
| //TODO: check whether "true | func_with_return" works |
| |
| re_execute_shell(to_free, |
| funcp->body_as_string, |
| G.global_argv[0], |
| argv + 1, |
| NULL); |
| # endif |
| } |
| |
| static int run_function(const struct function *funcp, char **argv) |
| { |
| int rc; |
| save_arg_t sv; |
| smallint sv_flg; |
| |
| save_and_replace_G_args(&sv, argv); |
| |
| /* "We are in function, ok to use return" */ |
| sv_flg = G_flag_return_in_progress; |
| G_flag_return_in_progress = -1; |
| |
| /* Make "local" variables properly shadow previous ones */ |
| IF_HUSH_LOCAL(enter_var_nest_level();) |
| IF_HUSH_LOCAL(G.func_nest_level++;) |
| |
| /* On MMU, funcp->body is always non-NULL */ |
| # if !BB_MMU |
| if (!funcp->body) { |
| /* Function defined by -F */ |
| parse_and_run_string(funcp->body_as_string); |
| rc = G.last_exitcode; |
| } else |
| # endif |
| { |
| rc = run_list(funcp->body); |
| } |
| |
| IF_HUSH_LOCAL(G.func_nest_level--;) |
| IF_HUSH_LOCAL(leave_var_nest_level();) |
| |
| G_flag_return_in_progress = sv_flg; |
| # if ENABLE_HUSH_TRAP |
| debug_printf_exec("G.return_exitcode=-1\n"); |
| G.return_exitcode = -1; /* invalidate stashed return value */ |
| # endif |
| |
| restore_G_args(&sv, argv); |
| |
| return rc; |
| } |
| #endif /* ENABLE_HUSH_FUNCTIONS */ |
| |
| |
| #if BB_MMU |
| #define exec_builtin(to_free, x, argv) \ |
| exec_builtin(x, argv) |
| #else |
| #define exec_builtin(to_free, x, argv) \ |
| exec_builtin(to_free, argv) |
| #endif |
| static void exec_builtin(char ***to_free, |
| const struct built_in_command *x, |
| char **argv) NORETURN; |
| static void exec_builtin(char ***to_free, |
| const struct built_in_command *x, |
| char **argv) |
| { |
| #if BB_MMU |
| int rcode; |
| //? close_saved_fds_and_FILE_fds(); |
| rcode = x->b_function(argv); |
| fflush_all(); |
| _exit(rcode); |
| #else |
| fflush_all(); |
| /* On NOMMU, we must never block! |
| * Example: { sleep 99 | read line; } & echo Ok |
| */ |
| re_execute_shell(to_free, |
| argv[0], |
| G.global_argv[0], |
| G.global_argv + 1, |
| argv); |
| #endif |
| } |
| |
| |
| static void execvp_or_die(char **argv) NORETURN; |
| static void execvp_or_die(char **argv) |
| { |
| int e; |
| debug_printf_exec("execing '%s'\n", argv[0]); |
| /* Don't propagate SIG_IGN to the child */ |
| if (SPECIAL_JOBSTOP_SIGS != 0) |
| switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS); |
| execvp(argv[0], argv); |
| e = 2; |
| if (errno == EACCES) e = 126; |
| if (errno == ENOENT) e = 127; |
| bb_perror_msg("can't execute '%s'", argv[0]); |
| _exit(e); |
| } |
| |
| #if ENABLE_HUSH_MODE_X |
| static void x_mode_print_optionally_squoted(const char *str) |
| { |
| unsigned len; |
| const char *cp; |
| |
| cp = str; |
| |
| /* the set of chars which-cause-string-to-be-squoted mimics bash */ |
| /* test a char with: bash -c 'set -x; echo "CH"' */ |
| if (str[strcspn(str, "\\\"'`$(){}[]<>;#&|~*?!^" |
| " " "\001\002\003\004\005\006\007" |
| "\010\011\012\013\014\015\016\017" |
| "\020\021\022\023\024\025\026\027" |
| "\030\031\032\033\034\035\036\037" |
| ) |
| ] == '\0' |
| ) { |
| /* string has no special chars */ |
| x_mode_addstr(str); |
| return; |
| } |
| |
| cp = str; |
| for (;;) { |
| /* print '....' up to EOL or first squote */ |
| len = (int)(strchrnul(cp, '\'') - cp); |
| if (len != 0) { |
| x_mode_addchr('\''); |
| x_mode_addblock(cp, len); |
| x_mode_addchr('\''); |
| cp += len; |
| } |
| if (*cp == '\0') |
| break; |
| /* string contains squote(s), print them as \' */ |
| x_mode_addchr('\\'); |
| x_mode_addchr('\''); |
| cp++; |
| } |
| } |
| static void dump_cmd_in_x_mode(char **argv) |
| { |
| if (G_x_mode && argv) { |
| unsigned n; |
| |
| /* "+[+++...][ cmd...]\n\0" */ |
| x_mode_prefix(); |
| n = 0; |
| while (argv[n]) { |
| x_mode_addchr(' '); |
| if (argv[n][0] == '\0') { |
| x_mode_addchr('\''); |
| x_mode_addchr('\''); |
| } else { |
| x_mode_print_optionally_squoted(argv[n]); |
| } |
| n++; |
| } |
| x_mode_flush(); |
| } |
| } |
| #else |
| # define dump_cmd_in_x_mode(argv) ((void)0) |
| #endif |
| |
| #if ENABLE_HUSH_COMMAND |
| static void if_command_vV_print_and_exit(char opt_vV, char *cmd, const char *explanation) |
| { |
| char *to_free; |
| |
| if (!opt_vV) |
| return; |
| |
| to_free = NULL; |
| if (!explanation) { |
| char *path = getenv("PATH"); |
| explanation = to_free = find_executable(cmd, &path); /* path == NULL is ok */ |
| if (!explanation) |
| _exit(1); /* PROG was not found */ |
| if (opt_vV != 'V') |
| cmd = to_free; /* -v PROG prints "/path/to/PROG" */ |
| } |
| printf((opt_vV == 'V') ? "%s is %s\n" : "%s\n", cmd, explanation); |
| free(to_free); |
| fflush_all(); |
| _exit(0); |
| } |
| #else |
| # define if_command_vV_print_and_exit(a,b,c) ((void)0) |
| #endif |
| |
| #if BB_MMU |
| #define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \ |
| pseudo_exec_argv(argv, assignment_cnt, argv_expanded) |
| #define pseudo_exec(nommu_save, command, argv_expanded) \ |
| pseudo_exec(command, argv_expanded) |
| #endif |
| |
| /* Called after [v]fork() in run_pipe, or from builtin_exec. |
| * Never returns. |
| * Don't exit() here. If you don't exec, use _exit instead. |
| * The at_exit handlers apparently confuse the calling process, |
| * in particular stdin handling. Not sure why? -- because of vfork! (vda) |
| */ |
| static void pseudo_exec_argv(nommu_save_t *nommu_save, |
| char **argv, int assignment_cnt, |
| char **argv_expanded) NORETURN; |
| static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save, |
| char **argv, int assignment_cnt, |
| char **argv_expanded) |
| { |
| const struct built_in_command *x; |
| struct variable **sv_shadowed; |
| char **new_env; |
| IF_HUSH_COMMAND(char opt_vV = 0;) |
| IF_HUSH_FUNCTIONS(const struct function *funcp;) |
| |
| new_env = expand_assignments(argv, assignment_cnt); |
| dump_cmd_in_x_mode(new_env); |
| |
| if (!argv[assignment_cnt]) { |
| /* Case when we are here: ... | var=val | ... |
| * (note that we do not exit early, i.e., do not optimize out |
| * expand_assignments(): think about ... | var=`sleep 1` | ... |
| */ |
| free_strings(new_env); |
| _exit(EXIT_SUCCESS); |
| } |
| |
| sv_shadowed = G.shadowed_vars_pp; |
| #if BB_MMU |
| G.shadowed_vars_pp = NULL; /* "don't save, free them instead" */ |
| #else |
| G.shadowed_vars_pp = &nommu_save->old_vars; |
| G.var_nest_level++; |
| #endif |
| set_vars_and_save_old(new_env); |
| G.shadowed_vars_pp = sv_shadowed; |
| |
| if (argv_expanded) { |
| argv = argv_expanded; |
| } else { |
| argv = expand_strvec_to_strvec(argv + assignment_cnt); |
| #if !BB_MMU |
| nommu_save->argv = argv; |
| #endif |
| } |
| dump_cmd_in_x_mode(argv); |
| |
| #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU |
| if (strchr(argv[0], '/') != NULL) |
| goto skip; |
| #endif |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| /* Check if the command matches any functions (this goes before bltins) */ |
| funcp = find_function(argv[0]); |
| if (funcp) |
| exec_function(&nommu_save->argv_from_re_execing, funcp, argv); |
| #endif |
| |
| #if ENABLE_HUSH_COMMAND |
| /* "command BAR": run BAR without looking it up among functions |
| * "command -v BAR": print "BAR" or "/path/to/BAR"; or exit 1 |
| * "command -V BAR": print "BAR is {a function,a shell builtin,/path/to/BAR}" |
| */ |
| while (strcmp(argv[0], "command") == 0 && argv[1]) { |
| char *p; |
| |
| argv++; |
| p = *argv; |
| if (p[0] != '-' || !p[1]) |
| continue; /* bash allows "command command command [-OPT] BAR" */ |
| |
| for (;;) { |
| p++; |
| switch (*p) { |
| case '\0': |
| argv++; |
| p = *argv; |
| if (p[0] != '-' || !p[1]) |
| goto after_opts; |
| continue; /* next arg is also -opts, process it too */ |
| case 'v': |
| case 'V': |
| opt_vV = *p; |
| continue; |
| default: |
| bb_error_msg_and_die("%s: %s: invalid option", "command", argv[0]); |
| } |
| } |
| } |
| after_opts: |
| # if ENABLE_HUSH_FUNCTIONS |
| if (opt_vV && find_function(argv[0])) |
| if_command_vV_print_and_exit(opt_vV, argv[0], "a function"); |
| # endif |
| #endif |
| |
| /* Check if the command matches any of the builtins. |
| * Depending on context, this might be redundant. But it's |
| * easier to waste a few CPU cycles than it is to figure out |
| * if this is one of those cases. |
| */ |
| /* Why "BB_MMU ? :" difference in logic? - |
| * On NOMMU, it is more expensive to re-execute shell |
| * just in order to run echo or test builtin. |
| * It's better to skip it here and run corresponding |
| * non-builtin later. */ |
| x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]); |
| if (x) { |
| if_command_vV_print_and_exit(opt_vV, argv[0], "a shell builtin"); |
| exec_builtin(&nommu_save->argv_from_re_execing, x, argv); |
| } |
| |
| #if ENABLE_FEATURE_SH_STANDALONE |
| /* Check if the command matches any busybox applets */ |
| { |
| int a = find_applet_by_name(argv[0]); |
| if (a >= 0) { |
| if_command_vV_print_and_exit(opt_vV, argv[0], "an applet"); |
| # if BB_MMU /* see above why on NOMMU it is not allowed */ |
| if (APPLET_IS_NOEXEC(a)) { |
| /* Do not leak open fds from opened script files etc. |
| * Testcase: interactive "ls -l /proc/self/fd" |
| * should not show tty fd open. |
| */ |
| close_saved_fds_and_FILE_fds(); |
| //FIXME: should also close saved redir fds |
| //This casuses test failures in |
| //redir_children_should_not_see_saved_fd_2.tests |
| //redir_children_should_not_see_saved_fd_3.tests |
| //if you replace "busybox find" with just "find" in them |
| /* Without this, "rm -i FILE" can't be ^C'ed: */ |
| switch_off_special_sigs(G.special_sig_mask); |
| debug_printf_exec("running applet '%s'\n", argv[0]); |
| run_noexec_applet_and_exit(a, argv[0], argv); |
| } |
| # endif |
| /* Re-exec ourselves */ |
| debug_printf_exec("re-execing applet '%s'\n", argv[0]); |
| /* Don't propagate SIG_IGN to the child */ |
| if (SPECIAL_JOBSTOP_SIGS != 0) |
| switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS); |
| execv(bb_busybox_exec_path, argv); |
| /* If they called chroot or otherwise made the binary no longer |
| * executable, fall through */ |
| } |
| } |
| #endif |
| |
| #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU |
| skip: |
| #endif |
| if_command_vV_print_and_exit(opt_vV, argv[0], NULL); |
| execvp_or_die(argv); |
| } |
| |
| /* Called after [v]fork() in run_pipe |
| */ |
| static void pseudo_exec(nommu_save_t *nommu_save, |
| struct command *command, |
| char **argv_expanded) NORETURN; |
| static void pseudo_exec(nommu_save_t *nommu_save, |
| struct command *command, |
| char **argv_expanded) |
| { |
| #if ENABLE_HUSH_FUNCTIONS |
| if (command->cmd_type == CMD_FUNCDEF) { |
| /* Ignore funcdefs in pipes: |
| * true | f() { cmd } |
| */ |
| _exit(0); |
| } |
| #endif |
| |
| if (command->argv) { |
| pseudo_exec_argv(nommu_save, command->argv, |
| command->assignment_cnt, argv_expanded); |
| } |
| |
| if (command->group) { |
| /* Cases when we are here: |
| * ( list ) |
| * { list } & |
| * ... | ( list ) | ... |
| * ... | { list } | ... |
| */ |
| #if BB_MMU |
| int rcode; |
| debug_printf_exec("pseudo_exec: run_list\n"); |
| reset_traps_to_defaults(); |
| rcode = run_list(command->group); |
| /* OK to leak memory by not calling free_pipe_list, |
| * since this process is about to exit */ |
| _exit(rcode); |
| #else |
| re_execute_shell(&nommu_save->argv_from_re_execing, |
| command->group_as_string, |
| G.global_argv[0], |
| G.global_argv + 1, |
| NULL); |
| #endif |
| } |
| |
| /* Case when we are here: ... | >file */ |
| debug_printf_exec("pseudo_exec'ed null command\n"); |
| _exit(EXIT_SUCCESS); |
| } |
| |
| #if ENABLE_HUSH_JOB |
| static const char *get_cmdtext(struct pipe *pi) |
| { |
| char **argv; |
| char *p; |
| int len; |
| |
| /* This is subtle. ->cmdtext is created only on first backgrounding. |
| * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...) |
| * On subsequent bg argv is trashed, but we won't use it */ |
| if (pi->cmdtext) |
| return pi->cmdtext; |
| |
| argv = pi->cmds[0].argv; |
| if (!argv) { |
| pi->cmdtext = xzalloc(1); |
| return pi->cmdtext; |
| } |
| len = 0; |
| do { |
| len += strlen(*argv) + 1; |
| } while (*++argv); |
| p = xmalloc(len); |
| pi->cmdtext = p; |
| argv = pi->cmds[0].argv; |
| do { |
| p = stpcpy(p, *argv); |
| *p++ = ' '; |
| } while (*++argv); |
| p[-1] = '\0'; |
| return pi->cmdtext; |
| } |
| |
| static void remove_job_from_table(struct pipe *pi) |
| { |
| struct pipe *prev_pipe; |
| |
| if (pi == G.job_list) { |
| G.job_list = pi->next; |
| } else { |
| prev_pipe = G.job_list; |
| while (prev_pipe->next != pi) |
| prev_pipe = prev_pipe->next; |
| prev_pipe->next = pi->next; |
| } |
| G.last_jobid = 0; |
| if (G.job_list) |
| G.last_jobid = G.job_list->jobid; |
| } |
| |
| static void delete_finished_job(struct pipe *pi) |
| { |
| remove_job_from_table(pi); |
| free_pipe(pi); |
| } |
| |
| static void clean_up_last_dead_job(void) |
| { |
| if (G.job_list && !G.job_list->alive_cmds) |
| delete_finished_job(G.job_list); |
| } |
| |
| static void insert_job_into_table(struct pipe *pi) |
| { |
| struct pipe *job, **jobp; |
| int i; |
| |
| clean_up_last_dead_job(); |
| |
| /* Find the end of the list, and find next job ID to use */ |
| i = 0; |
| jobp = &G.job_list; |
| while ((job = *jobp) != NULL) { |
| if (job->jobid > i) |
| i = job->jobid; |
| jobp = &job->next; |
| } |
| pi->jobid = i + 1; |
| |
| /* Create a new job struct at the end */ |
| job = *jobp = xmemdup(pi, sizeof(*pi)); |
| job->next = NULL; |
| job->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds); |
| /* Cannot copy entire pi->cmds[] vector! This causes double frees */ |
| for (i = 0; i < pi->num_cmds; i++) { |
| job->cmds[i].pid = pi->cmds[i].pid; |
| /* all other fields are not used and stay zero */ |
| } |
| job->cmdtext = xstrdup(get_cmdtext(pi)); |
| |
| if (G_interactive_fd) |
| printf("[%u] %u %s\n", job->jobid, (unsigned)job->cmds[0].pid, job->cmdtext); |
| G.last_jobid = job->jobid; |
| } |
| #endif /* JOB */ |
| |
| static int job_exited_or_stopped(struct pipe *pi) |
| { |
| int rcode, i; |
| |
| if (pi->alive_cmds != pi->stopped_cmds) |
| return -1; |
| |
| /* All processes in fg pipe have exited or stopped */ |
| rcode = 0; |
| i = pi->num_cmds; |
| while (--i >= 0) { |
| rcode = pi->cmds[i].cmd_exitcode; |
| /* usually last process gives overall exitstatus, |
| * but with "set -o pipefail", last *failed* process does */ |
| if (G.o_opt[OPT_O_PIPEFAIL] == 0 || rcode != 0) |
| break; |
| } |
| IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) |
| return rcode; |
| } |
| |
| static int process_wait_result(struct pipe *fg_pipe, pid_t childpid, int status) |
| { |
| #if ENABLE_HUSH_JOB |
| struct pipe *pi; |
| #endif |
| int i, dead; |
| |
| dead = WIFEXITED(status) || WIFSIGNALED(status); |
| |
| #if DEBUG_JOBS |
| if (WIFSTOPPED(status)) |
| debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n", |
| childpid, WSTOPSIG(status), WEXITSTATUS(status)); |
| if (WIFSIGNALED(status)) |
| debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n", |
| childpid, WTERMSIG(status), WEXITSTATUS(status)); |
| if (WIFEXITED(status)) |
| debug_printf_jobs("pid %d exited, exitcode %d\n", |
| childpid, WEXITSTATUS(status)); |
| #endif |
| /* Were we asked to wait for a fg pipe? */ |
| if (fg_pipe) { |
| i = fg_pipe->num_cmds; |
| |
| while (--i >= 0) { |
| int rcode; |
| |
| debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid); |
| if (fg_pipe->cmds[i].pid != childpid) |
| continue; |
| if (dead) { |
| int ex; |
| fg_pipe->cmds[i].pid = 0; |
| fg_pipe->alive_cmds--; |
| ex = WEXITSTATUS(status); |
| /* bash prints killer signal's name for *last* |
| * process in pipe (prints just newline for SIGINT/SIGPIPE). |
| * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT) |
| */ |
| if (WIFSIGNALED(status)) { |
| int sig = WTERMSIG(status); |
| #if ENABLE_HUSH_JOB |
| if (G.run_list_level == 1 |
| /* ^^^^^ Do not print in nested contexts, example: |
| * echo `sleep 1; sh -c 'kill -9 $$'` - prints "137", NOT "Killed 137" |
| */ |
| && i == fg_pipe->num_cmds-1 |
| ) { |
| /* strsignal() is for bash compat. ~600 bloat versus bbox's get_signame() */ |
| puts(sig == SIGINT || sig == SIGPIPE ? "" : strsignal(sig)); |
| } |
| #endif |
| /* TODO: if (WCOREDUMP(status)) + " (core dumped)"; */ |
| /* MIPS has 128 sigs (1..128), if sig==128, |
| * 128 + sig would result in exitcode 256 -> 0! |
| */ |
| ex = 128 | sig; |
| } |
| fg_pipe->cmds[i].cmd_exitcode = ex; |
| } else { |
| fg_pipe->stopped_cmds++; |
| } |
| debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n", |
| fg_pipe->alive_cmds, fg_pipe->stopped_cmds); |
| rcode = job_exited_or_stopped(fg_pipe); |
| if (rcode >= 0) { |
| /* Note: *non-interactive* bash does not continue if all processes in fg pipe |
| * are stopped. Testcase: "cat | cat" in a script (not on command line!) |
| * and "killall -STOP cat" */ |
| if (G_interactive_fd) { |
| #if ENABLE_HUSH_JOB |
| if (fg_pipe->alive_cmds != 0) |
| insert_job_into_table(fg_pipe); |
| #endif |
| return rcode; |
| } |
| if (fg_pipe->alive_cmds == 0) |
| return rcode; |
| } |
| /* There are still running processes in the fg_pipe */ |
| return -1; |
| } |
| /* It wasn't in fg_pipe, look for process in bg pipes */ |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* We were asked to wait for bg or orphaned children */ |
| /* No need to remember exitcode in this case */ |
| for (pi = G.job_list; pi; pi = pi->next) { |
| for (i = 0; i < pi->num_cmds; i++) { |
| if (pi->cmds[i].pid == childpid) |
| goto found_pi_and_prognum; |
| } |
| } |
| /* Happens when shell is used as init process (init=/bin/sh) */ |
| debug_printf("checkjobs: pid %d was not in our list!\n", childpid); |
| return -1; /* this wasn't a process from fg_pipe */ |
| |
| found_pi_and_prognum: |
| if (dead) { |
| /* child exited */ |
| int rcode = WEXITSTATUS(status); |
| if (WIFSIGNALED(status)) |
| /* NB: not 128 + sig, MIPS has sig 128 */ |
| rcode = 128 | WTERMSIG(status); |
| pi->cmds[i].cmd_exitcode = rcode; |
| if (G.last_bg_pid == pi->cmds[i].pid) |
| G.last_bg_pid_exitcode = rcode; |
| pi->cmds[i].pid = 0; |
| pi->alive_cmds--; |
| if (!pi->alive_cmds) { |
| # if ENABLE_HUSH_BASH_COMPAT |
| G.dead_job_exitcode = job_exited_or_stopped(pi); |
| # endif |
| if (G_interactive_fd) { |
| printf(JOB_STATUS_FORMAT, pi->jobid, |
| "Done", pi->cmdtext); |
| delete_finished_job(pi); |
| } else { |
| /* |
| * bash deletes finished jobs from job table only in interactive mode, |
| * after "jobs" cmd, or if pid of a new process matches one of the old ones |
| * (see cleanup_dead_jobs(), delete_old_job(), J_NOTIFIED in bash source). |
| * Testcase script: "(exit 3) & sleep 1; wait %1; echo $?" prints 3 in bash. |
| * We only retain one "dead" job, if it's the single job on the list. |
| * This covers most of real-world scenarios where this is useful. |
| */ |
| if (pi != G.job_list) |
| delete_finished_job(pi); |
| } |
| } |
| } else { |
| /* child stopped */ |
| pi->stopped_cmds++; |
| } |
| #endif |
| return -1; /* this wasn't a process from fg_pipe */ |
| } |
| |
| /* Check to see if any processes have exited -- if they have, |
| * figure out why and see if a job has completed. |
| * |
| * If non-NULL fg_pipe: wait for its completion or stop. |
| * Return its exitcode or zero if stopped. |
| * |
| * Alternatively (fg_pipe == NULL, waitfor_pid != 0): |
| * waitpid(WNOHANG), if waitfor_pid exits or stops, return exitcode+1, |
| * else return <0 if waitpid errors out (e.g. ECHILD: nothing to wait for) |
| * or 0 if no children changed status. |
| * |
| * Alternatively (fg_pipe == NULL, waitfor_pid == 0), |
| * return <0 if waitpid errors out (e.g. ECHILD: nothing to wait for) |
| * or 0 if no children changed status. |
| */ |
| static int checkjobs(struct pipe *fg_pipe, pid_t waitfor_pid) |
| { |
| int attributes; |
| int status; |
| int rcode = 0; |
| |
| debug_printf_jobs("checkjobs %p\n", fg_pipe); |
| |
| attributes = WUNTRACED; |
| if (fg_pipe == NULL) |
| attributes |= WNOHANG; |
| |
| errno = 0; |
| #if ENABLE_HUSH_FAST |
| if (G.handled_SIGCHLD == G.count_SIGCHLD) { |
| //bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p", |
| //getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe); |
| /* There was neither fork nor SIGCHLD since last waitpid */ |
| /* Avoid doing waitpid syscall if possible */ |
| if (!G.we_have_children) { |
| errno = ECHILD; |
| return -1; |
| } |
| if (fg_pipe == NULL) { /* is WNOHANG set? */ |
| /* We have children, but they did not exit |
| * or stop yet (we saw no SIGCHLD) */ |
| return 0; |
| } |
| /* else: !WNOHANG, waitpid will block, can't short-circuit */ |
| } |
| #endif |
| |
| /* Do we do this right? |
| * bash-3.00# sleep 20 | false |
| * <ctrl-Z pressed> |
| * [3]+ Stopped sleep 20 | false |
| * bash-3.00# echo $? |
| * 1 <========== bg pipe is not fully done, but exitcode is already known! |
| * [hush 1.14.0: yes we do it right] |
| */ |
| while (1) { |
| pid_t childpid; |
| #if ENABLE_HUSH_FAST |
| int i; |
| i = G.count_SIGCHLD; |
| #endif |
| childpid = waitpid(-1, &status, attributes); |
| if (childpid <= 0) { |
| if (childpid && errno != ECHILD) |
| bb_simple_perror_msg("waitpid"); |
| #if ENABLE_HUSH_FAST |
| else { /* Until next SIGCHLD, waitpid's are useless */ |
| G.we_have_children = (childpid == 0); |
| G.handled_SIGCHLD = i; |
| //bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| } |
| #endif |
| /* ECHILD (no children), or 0 (no change in children status) */ |
| rcode = childpid; |
| break; |
| } |
| rcode = process_wait_result(fg_pipe, childpid, status); |
| if (rcode >= 0) { |
| /* fg_pipe exited or stopped */ |
| break; |
| } |
| if (childpid == waitfor_pid) { /* "wait PID" */ |
| debug_printf_exec("childpid==waitfor_pid:%d status:0x%08x\n", childpid, status); |
| rcode = WEXITSTATUS(status); |
| if (WIFSIGNALED(status)) |
| rcode = 128 | WTERMSIG(status); |
| if (WIFSTOPPED(status)) |
| /* bash: "cmd & wait $!" and cmd stops: $? = 128 | stopsig */ |
| rcode = 128 | WSTOPSIG(status); |
| rcode++; |
| break; /* "wait PID" called us, give it exitcode+1 */ |
| } |
| #if ENABLE_HUSH_BASH_COMPAT |
| if (-1 == waitfor_pid /* "wait -n" (wait for any one job) */ |
| && G.dead_job_exitcode >= 0 /* some job did finish */ |
| ) { |
| debug_printf_exec("waitfor_pid:-1\n"); |
| rcode = G.dead_job_exitcode + 1; |
| break; |
| } |
| #endif |
| /* This wasn't one of our processes, or */ |
| /* fg_pipe still has running processes, do waitpid again */ |
| } /* while (waitpid succeeds)... */ |
| |
| return rcode; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| static int checkjobs_and_fg_shell(struct pipe *fg_pipe) |
| { |
| pid_t p; |
| int rcode = checkjobs(fg_pipe, 0 /*(no pid to wait for)*/); |
| if (G_saved_tty_pgrp) { |
| /* Job finished, move the shell to the foreground */ |
| p = getpgrp(); /* our process group id */ |
| debug_printf_jobs("fg'ing ourself: getpgrp()=%d\n", (int)p); |
| tcsetpgrp(G_interactive_fd, p); |
| } |
| return rcode; |
| } |
| #endif |
| |
| /* Start all the jobs, but don't wait for anything to finish. |
| * See checkjobs(). |
| * |
| * Return code is normally -1, when the caller has to wait for children |
| * to finish to determine the exit status of the pipe. If the pipe |
| * is a simple builtin command, however, the action is done by the |
| * time run_pipe returns, and the exit code is provided as the |
| * return value. |
| * |
| * Returns -1 only if started some children. IOW: we have to |
| * mask out retvals of builtins etc with 0xff! |
| * |
| * The only case when we do not need to [v]fork is when the pipe |
| * is single, non-backgrounded, non-subshell command. Examples: |
| * cmd ; ... { list } ; ... |
| * cmd && ... { list } && ... |
| * cmd || ... { list } || ... |
| * If it is, then we can run cmd as a builtin, NOFORK, |
| * or (if SH_STANDALONE) an applet, and we can run the { list } |
| * with run_list. If it isn't one of these, we fork and exec cmd. |
| * |
| * Cases when we must fork: |
| * non-single: cmd | cmd |
| * backgrounded: cmd & { list } & |
| * subshell: ( list ) [&] |
| */ |
| #if !ENABLE_HUSH_MODE_X |
| #define redirect_and_varexp_helper(command, sqp, argv_expanded) \ |
| redirect_and_varexp_helper(command, sqp) |
| #endif |
| static int redirect_and_varexp_helper( |
| struct command *command, |
| struct squirrel **sqp, |
| char **argv_expanded) |
| { |
| /* Assignments occur before redirects. Try: |
| * a=`sleep 1` sleep 2 3>/qwe/rty |
| */ |
| |
| char **new_env = expand_assignments(command->argv, command->assignment_cnt); |
| dump_cmd_in_x_mode(new_env); |
| dump_cmd_in_x_mode(argv_expanded); |
| /* this takes ownership of new_env[i] elements, and frees new_env: */ |
| set_vars_and_save_old(new_env); |
| |
| return setup_redirects(command, sqp); |
| } |
| static NOINLINE int run_pipe(struct pipe *pi) |
| { |
| static const char *const null_ptr = NULL; |
| |
| int cmd_no; |
| int next_infd; |
| struct command *command; |
| char **argv_expanded; |
| char **argv; |
| struct squirrel *squirrel = NULL; |
| int rcode; |
| |
| debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds); |
| debug_enter(); |
| |
| /* Testcase: set -- q w e; (IFS='' echo "$*"; IFS=''; echo "$*"); echo "$*" |
| * Result should be 3 lines: q w e, qwe, q w e |
| */ |
| if (G.ifs_whitespace != G.ifs) |
| free(G.ifs_whitespace); |
| G.ifs = get_local_var_value("IFS"); |
| if (G.ifs) { |
| char *p; |
| G.ifs_whitespace = (char*)G.ifs; |
| p = skip_whitespace(G.ifs); |
| if (*p) { |
| /* Not all $IFS is whitespace */ |
| char *d; |
| int len = p - G.ifs; |
| p = skip_non_whitespace(p); |
| G.ifs_whitespace = xmalloc(len + strlen(p) + 1); /* can overestimate */ |
| d = mempcpy(G.ifs_whitespace, G.ifs, len); |
| while (*p) { |
| if (isspace(*p)) |
| *d++ = *p; |
| p++; |
| } |
| *d = '\0'; |
| } |
| } else { |
| G.ifs = defifs; |
| G.ifs_whitespace = (char*)G.ifs; |
| } |
| |
| IF_HUSH_JOB(pi->pgrp = -1;) |
| pi->stopped_cmds = 0; |
| command = &pi->cmds[0]; |
| argv_expanded = NULL; |
| |
| if (pi->num_cmds != 1 |
| || pi->followup == PIPE_BG |
| || command->cmd_type == CMD_SUBSHELL |
| ) { |
| goto must_fork; |
| } |
| |
| pi->alive_cmds = 1; |
| |
| debug_printf_exec(": group:%p argv:'%s'\n", |
| command->group, command->argv ? command->argv[0] : "NONE"); |
| |
| if (command->group) { |
| #if ENABLE_HUSH_FUNCTIONS |
| if (command->cmd_type == CMD_FUNCDEF) { |
| /* "executing" func () { list } */ |
| struct function *funcp; |
| |
| funcp = new_function(command->argv[0]); |
| /* funcp->name is already set to argv[0] */ |
| funcp->body = command->group; |
| # if !BB_MMU |
| funcp->body_as_string = command->group_as_string; |
| command->group_as_string = NULL; |
| # endif |
| command->group = NULL; |
| command->argv[0] = NULL; |
| debug_printf_exec("cmd %p has child func at %p\n", command, funcp); |
| funcp->parent_cmd = command; |
| command->child_func = funcp; |
| |
| debug_printf_exec("run_pipe: return EXIT_SUCCESS\n"); |
| debug_leave(); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| /* { list } */ |
| debug_printf_exec("non-subshell group\n"); |
| rcode = 1; /* exitcode if redir failed */ |
| if (setup_redirects(command, &squirrel) == 0) { |
| debug_printf_exec(": run_list\n"); |
| //FIXME: we need to pass squirrel down into run_list() |
| //for SH_STANDALONE case, or else this construct: |
| // { find /proc/self/fd; true; } >FILE; cmd2 |
| //has no way of closing saved fd#1 for "find", |
| //and in SH_STANDALONE mode, "find" is not execed, |
| //therefore CLOEXEC on saved fd does not help. |
| rcode = run_list(command->group) & 0xff; |
| } |
| restore_redirects(squirrel); |
| IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) |
| debug_leave(); |
| debug_printf_exec("run_pipe: return %d\n", rcode); |
| return rcode; |
| } |
| |
| argv = command->argv ? command->argv : (char **) &null_ptr; |
| { |
| const struct built_in_command *x; |
| IF_HUSH_FUNCTIONS(const struct function *funcp;) |
| IF_NOT_HUSH_FUNCTIONS(enum { funcp = 0 };) |
| struct variable **sv_shadowed; |
| struct variable *old_vars; |
| |
| #if ENABLE_HUSH_LINENO_VAR |
| G.execute_lineno = command->lineno; |
| #endif |
| |
| if (argv[command->assignment_cnt] == NULL) { |
| /* Assignments, but no command. |
| * Ensure redirects take effect (that is, create files). |
| * Try "a=t >file" |
| */ |
| unsigned i; |
| G.expand_exitcode = 0; |
| only_assignments: |
| rcode = setup_redirects(command, &squirrel); |
| restore_redirects(squirrel); |
| |
| /* Set shell variables */ |
| i = 0; |
| while (i < command->assignment_cnt) { |
| char *p = expand_string_to_string(argv[i], |
| EXP_FLAG_ESC_GLOB_CHARS, |
| /*unbackslash:*/ 1 |
| ); |
| #if ENABLE_HUSH_MODE_X |
| if (G_x_mode) { |
| char *eq; |
| if (i == 0) |
| x_mode_prefix(); |
| x_mode_addchr(' '); |
| eq = strchrnul(p, '='); |
| if (*eq) eq++; |
| x_mode_addblock(p, (eq - p)); |
| x_mode_print_optionally_squoted(eq); |
| x_mode_flush(); |
| } |
| #endif |
| debug_printf_env("set shell var:'%s'->'%s'\n", *argv, p); |
| if (set_local_var(p, /*flag:*/ 0)) { |
| /* assignment to readonly var / putenv error? */ |
| rcode = 1; |
| } |
| i++; |
| } |
| /* Redirect error sets $? to 1. Otherwise, |
| * if evaluating assignment value set $?, retain it. |
| * Else, clear $?: |
| * false; q=`exit 2`; echo $? - should print 2 |
| * false; x=1; echo $? - should print 0 |
| * Because of the 2nd case, we can't just use G.last_exitcode. |
| */ |
| if (rcode == 0) |
| rcode = G.expand_exitcode; |
| IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) |
| debug_leave(); |
| debug_printf_exec("run_pipe: return %d\n", rcode); |
| return rcode; |
| } |
| |
| /* Expand the rest into (possibly) many strings each */ |
| #if defined(CMD_TEST2_SINGLEWORD_NOGLOB) |
| if (command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB) |
| argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt); |
| else |
| #endif |
| #if defined(CMD_SINGLEWORD_NOGLOB) |
| if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) |
| argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt); |
| else |
| #endif |
| argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt); |
| |
| /* If someone gives us an empty string: `cmd with empty output` */ |
| if (!argv_expanded[0]) { |
| free(argv_expanded); |
| /* `false` still has to set exitcode 1 */ |
| G.expand_exitcode = G.last_exitcode; |
| goto only_assignments; |
| } |
| |
| old_vars = NULL; |
| sv_shadowed = G.shadowed_vars_pp; |
| |
| /* Check if argv[0] matches any functions (this goes before bltins) */ |
| IF_HUSH_FUNCTIONS(funcp = find_function(argv_expanded[0]);) |
| IF_HUSH_FUNCTIONS(x = NULL;) |
| IF_HUSH_FUNCTIONS(if (!funcp)) |
| x = find_builtin(argv_expanded[0]); |
| if (x || funcp) { |
| if (x && x->b_function == builtin_exec && argv_expanded[1] == NULL) { |
| debug_printf("exec with redirects only\n"); |
| /* |
| * Variable assignments are executed, but then "forgotten": |
| * a=`sleep 1;echo A` exec 3>&-; echo $a |
| * sleeps, but prints nothing. |
| */ |
| enter_var_nest_level(); |
| G.shadowed_vars_pp = &old_vars; |
| rcode = redirect_and_varexp_helper(command, |
| /*squirrel:*/ ERR_PTR, |
| argv_expanded |
| ); |
| G.shadowed_vars_pp = sv_shadowed; |
| /* rcode=1 can be if redir file can't be opened */ |
| |
| goto clean_up_and_ret1; |
| } |
| |
| /* Bump var nesting, or this will leak exported $a: |
| * a=b true; env | grep ^a= |
| */ |
| enter_var_nest_level(); |
| /* Collect all variables "shadowed" by helper |
| * (IOW: old vars overridden by "var1=val1 var2=val2 cmd..." syntax) |
| * into old_vars list: |
| */ |
| G.shadowed_vars_pp = &old_vars; |
| rcode = redirect_and_varexp_helper(command, &squirrel, argv_expanded); |
| if (rcode == 0) { |
| if (!funcp) { |
| /* Do not collect *to old_vars list* vars shadowed |
| * by e.g. "local VAR" builtin (collect them |
| * in the previously nested list instead): |
| * don't want them to be restored immediately |
| * after "local" completes. |
| */ |
| G.shadowed_vars_pp = sv_shadowed; |
| |
| debug_printf_exec(": builtin '%s' '%s'...\n", |
| x->b_cmd, argv_expanded[1]); |
| fflush_all(); |
| rcode = x->b_function(argv_expanded) & 0xff; |
| fflush_all(); |
| } |
| #if ENABLE_HUSH_FUNCTIONS |
| else { |
| debug_printf_exec(": function '%s' '%s'...\n", |
| funcp->name, argv_expanded[1]); |
| rcode = run_function(funcp, argv_expanded) & 0xff; |
| /* |
| * But do collect *to old_vars list* vars shadowed |
| * within function execution. To that end, restore |
| * this pointer _after_ function run: |
| */ |
| G.shadowed_vars_pp = sv_shadowed; |
| } |
| #endif |
| } |
| } else |
| if (ENABLE_FEATURE_SH_NOFORK && NUM_APPLETS > 1) { |
| int n = find_applet_by_name(argv_expanded[0]); |
| if (n < 0 || !APPLET_IS_NOFORK(n)) |
| goto must_fork; |
| |
| enter_var_nest_level(); |
| /* Collect all variables "shadowed" by helper into old_vars list */ |
| G.shadowed_vars_pp = &old_vars; |
| rcode = redirect_and_varexp_helper(command, &squirrel, argv_expanded); |
| G.shadowed_vars_pp = sv_shadowed; |
| |
| if (rcode == 0) { |
| debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", |
| argv_expanded[0], argv_expanded[1]); |
| /* |
| * Note: signals (^C) can't interrupt here. |
| * We remember them and they will be acted upon |
| * after applet returns. |
| * This makes applets which can run for a long time |
| * and/or wait for user input ineligible for NOFORK: |
| * for example, "yes" or "rm" (rm -i waits for input). |
| */ |
| rcode = run_nofork_applet(n, argv_expanded); |
| } |
| } else |
| goto must_fork; |
| |
| restore_redirects(squirrel); |
| clean_up_and_ret1: |
| leave_var_nest_level(); |
| add_vars(old_vars); |
| |
| /* |
| * Try "usleep 99999999" + ^C + "echo $?" |
| * with FEATURE_SH_NOFORK=y. |
| */ |
| if (!funcp) { |
| /* It was builtin or nofork. |
| * if this would be a real fork/execed program, |
| * it should have died if a fatal sig was received. |
| * But OTOH, there was no separate process, |
| * the sig was sent to _shell_, not to non-existing |
| * child. |
| * Let's just handle ^C only, this one is obvious: |
| * we aren't ok with exitcode 0 when ^C was pressed |
| * during builtin/nofork. |
| */ |
| if (sigismember(&G.pending_set, SIGINT)) |
| rcode = 128 | SIGINT; |
| } |
| free(argv_expanded); |
| IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) |
| debug_leave(); |
| debug_printf_exec("run_pipe return %d\n", rcode); |
| return rcode; |
| } |
| |
| must_fork: |
| /* NB: argv_expanded may already be created, and that |
| * might include `cmd` runs! Do not rerun it! We *must* |
| * use argv_expanded if it's non-NULL */ |
| |
| /* Going to fork a child per each pipe member */ |
| pi->alive_cmds = 0; |
| next_infd = 0; |
| |
| cmd_no = 0; |
| while (cmd_no < pi->num_cmds) { |
| struct fd_pair pipefds; |
| #if !BB_MMU |
| int sv_var_nest_level = G.var_nest_level; |
| volatile nommu_save_t nommu_save; |
| nommu_save.old_vars = NULL; |
| nommu_save.argv = NULL; |
| nommu_save.argv_from_re_execing = NULL; |
| #endif |
| command = &pi->cmds[cmd_no]; |
| cmd_no++; |
| if (command->argv) { |
| debug_printf_exec(": pipe member '%s' '%s'...\n", |
| command->argv[0], command->argv[1]); |
| } else { |
| debug_printf_exec(": pipe member with no argv\n"); |
| } |
| |
| /* pipes are inserted between pairs of commands */ |
| pipefds.rd = 0; |
| pipefds.wr = 1; |
| if (cmd_no < pi->num_cmds) |
| xpiped_pair(pipefds); |
| |
| #if ENABLE_HUSH_LINENO_VAR |
| G.execute_lineno = command->lineno; |
| #endif |
| |
| command->pid = BB_MMU ? fork() : vfork(); |
| if (!command->pid) { /* child */ |
| #if ENABLE_HUSH_JOB |
| disable_restore_tty_pgrp_on_exit(); |
| CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */ |
| |
| /* Every child adds itself to new process group |
| * with pgid == pid_of_first_child_in_pipe */ |
| if (G.run_list_level == 1 && G_interactive_fd) { |
| pid_t pgrp; |
| pgrp = pi->pgrp; |
| if (pgrp < 0) /* true for 1st process only */ |
| pgrp = getpid(); |
| if (setpgid(0, pgrp) == 0 |
| && pi->followup != PIPE_BG |
| && G_saved_tty_pgrp /* we have ctty */ |
| ) { |
| /* We do it in *every* child, not just first, |
| * to avoid races */ |
| tcsetpgrp(G_interactive_fd, pgrp); |
| } |
| } |
| #endif |
| if (pi->alive_cmds == 0 && pi->followup == PIPE_BG) { |
| /* 1st cmd in backgrounded pipe |
| * should have its stdin /dev/null'ed */ |
| close(0); |
| if (open(bb_dev_null, O_RDONLY)) |
| xopen("/", O_RDONLY); |
| } else { |
| xmove_fd(next_infd, 0); |
| } |
| xmove_fd(pipefds.wr, 1); |
| if (pipefds.rd > 1) |
| close(pipefds.rd); |
| /* Like bash, explicit redirects override pipes, |
| * and the pipe fd (fd#1) is available for dup'ing: |
| * "cmd1 2>&1 | cmd2": fd#1 is duped to fd#2, thus stderr |
| * of cmd1 goes into pipe. |
| */ |
| if (setup_redirects(command, NULL)) { |
| /* Happens when redir file can't be opened: |
| * $ hush -c 'echo FOO >&2 | echo BAR 3>/qwe/rty; echo BAZ' |
| * FOO |
| * hush: can't open '/qwe/rty': No such file or directory |
| * BAZ |
| * (echo BAR is not executed, it hits _exit(1) below) |
| */ |
| _exit(1); |
| } |
| |
| /* Stores to nommu_save list of env vars putenv'ed |
| * (NOMMU, on MMU we don't need that) */ |
| /* cast away volatility... */ |
| pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded); |
| /* pseudo_exec() does not return */ |
| } |
| |
| /* parent or error */ |
| #if ENABLE_HUSH_FAST |
| G.count_SIGCHLD++; |
| //bb_error_msg("[%d] fork in run_pipe: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD); |
| #endif |
| enable_restore_tty_pgrp_on_exit(); |
| #if !BB_MMU |
| /* Clean up after vforked child */ |
| free(nommu_save.argv); |
| free(nommu_save.argv_from_re_execing); |
| G.var_nest_level = sv_var_nest_level; |
| remove_nested_vars(); |
| add_vars(nommu_save.old_vars); |
| #endif |
| free(argv_expanded); |
| argv_expanded = NULL; |
| if (command->pid < 0) { /* [v]fork failed */ |
| /* Clearly indicate, was it fork or vfork */ |
| bb_simple_perror_msg(BB_MMU ? "vfork"+1 : "vfork"); |
| } else { |
| pi->alive_cmds++; |
| #if ENABLE_HUSH_JOB |
| /* Second and next children need to know pid of first one */ |
| if (pi->pgrp < 0) |
| pi->pgrp = command->pid; |
| #endif |
| } |
| |
| if (cmd_no > 1) |
| close(next_infd); |
| if (cmd_no < pi->num_cmds) |
| close(pipefds.wr); |
| /* Pass read (output) pipe end to next iteration */ |
| next_infd = pipefds.rd; |
| } |
| |
| if (!pi->alive_cmds) { |
| debug_leave(); |
| debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n"); |
| return 1; |
| } |
| |
| debug_leave(); |
| debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds); |
| return -1; |
| } |
| |
| /* NB: called by pseudo_exec, and therefore must not modify any |
| * global data until exec/_exit (we can be a child after vfork!) */ |
| static int run_list(struct pipe *pi) |
| { |
| #if ENABLE_HUSH_CASE |
| char *case_word = NULL; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| struct pipe *loop_top = NULL; |
| char **for_lcur = NULL; |
| char **for_list = NULL; |
| #endif |
| smallint last_followup; |
| smalluint rcode; |
| #if ENABLE_HUSH_IF || ENABLE_HUSH_CASE |
| smalluint cond_code = 0; |
| #else |
| enum { cond_code = 0 }; |
| #endif |
| #if HAS_KEYWORDS |
| smallint rword; /* RES_foo */ |
| smallint last_rword; /* ditto */ |
| #endif |
| |
| debug_printf_exec("run_list start lvl %d\n", G.run_list_level); |
| debug_enter(); |
| |
| #if ENABLE_HUSH_LOOPS |
| /* Check syntax for "for" */ |
| { |
| struct pipe *cpipe; |
| for (cpipe = pi; cpipe; cpipe = cpipe->next) { |
| if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN) |
| continue; |
| /* current word is FOR or IN (BOLD in comments below) */ |
| if (cpipe->next == NULL) { |
| syntax_error("malformed for"); |
| debug_leave(); |
| debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level); |
| return 1; |
| } |
| /* "FOR v; do ..." and "for v IN a b; do..." are ok */ |
| if (cpipe->next->res_word == RES_DO) |
| continue; |
| /* next word is not "do". It must be "in" then ("FOR v in ...") */ |
| if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */ |
| || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */ |
| ) { |
| syntax_error("malformed for"); |
| debug_leave(); |
| debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level); |
| return 1; |
| } |
| } |
| } |
| #endif |
| |
| /* Past this point, all code paths should jump to ret: label |
| * in order to return, no direct "return" statements please. |
| * This helps to ensure that no memory is leaked. */ |
| |
| #if ENABLE_HUSH_JOB |
| G.run_list_level++; |
| #endif |
| |
| #if HAS_KEYWORDS |
| rword = RES_NONE; |
| last_rword = RES_XXXX; |
| #endif |
| last_followup = PIPE_SEQ; |
| rcode = G.last_exitcode; |
| |
| /* Go through list of pipes, (maybe) executing them. */ |
| for (; pi; pi = IF_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) { |
| int r; |
| int sv_errexit_depth; |
| |
| if (G.flag_SIGINT) |
| break; |
| if (G_flag_return_in_progress == 1) |
| break; |
| |
| IF_HAS_KEYWORDS(rword = pi->res_word;) |
| debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n", |
| rword, cond_code, last_rword); |
| |
| sv_errexit_depth = G.errexit_depth; |
| if ( |
| #if ENABLE_HUSH_IF |
| rword == RES_IF || rword == RES_ELIF || |
| #endif |
| pi->followup != PIPE_SEQ |
| ) { |
| G.errexit_depth++; |
| } |
| #if ENABLE_HUSH_LOOPS |
| if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR) |
| && loop_top == NULL /* avoid bumping G.depth_of_loop twice */ |
| ) { |
| /* start of a loop: remember where loop starts */ |
| loop_top = pi; |
| G.depth_of_loop++; |
| } |
| #endif |
| /* Still in the same "if...", "then..." or "do..." branch? */ |
| if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) { |
| if ((rcode == 0 && last_followup == PIPE_OR) |
| || (rcode != 0 && last_followup == PIPE_AND) |
| ) { |
| /* It is "<true> || CMD" or "<false> && CMD" |
| * and we should not execute CMD */ |
| debug_printf_exec("skipped cmd because of || or &&\n"); |
| last_followup = pi->followup; |
| goto dont_check_jobs_but_continue; |
| } |
| } |
| last_followup = pi->followup; |
| IF_HAS_KEYWORDS(last_rword = rword;) |
| #if ENABLE_HUSH_IF |
| if (cond_code) { |
| if (rword == RES_THEN) { |
| /* if false; then ... fi has exitcode 0! */ |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| /* "if <false> THEN cmd": skip cmd */ |
| continue; |
| } |
| } else { |
| if (rword == RES_ELSE || rword == RES_ELIF) { |
| /* "if <true> then ... ELSE/ELIF cmd": |
| * skip cmd and all following ones */ |
| break; |
| } |
| } |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */ |
| if (!for_lcur) { |
| /* first loop through for */ |
| |
| static const char encoded_dollar_at[] ALIGN1 = { |
| SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0' |
| }; /* encoded representation of "$@" */ |
| static const char *const encoded_dollar_at_argv[] = { |
| encoded_dollar_at, NULL |
| }; /* argv list with one element: "$@" */ |
| char **vals; |
| |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| vals = (char**)encoded_dollar_at_argv; |
| if (pi->next->res_word == RES_IN) { |
| /* if no variable values after "in" we skip "for" */ |
| if (!pi->next->cmds[0].argv) { |
| debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n"); |
| break; |
| } |
| vals = pi->next->cmds[0].argv; |
| } /* else: "for var; do..." -> assume "$@" list */ |
| /* create list of variable values */ |
| debug_print_strings("for_list made from", vals); |
| for_list = expand_strvec_to_strvec(vals); |
| for_lcur = for_list; |
| debug_print_strings("for_list", for_list); |
| } |
| if (!*for_lcur) { |
| /* "for" loop is over, clean up */ |
| free(for_list); |
| for_list = NULL; |
| for_lcur = NULL; |
| break; |
| } |
| /* Insert next value from for_lcur */ |
| /* note: *for_lcur already has quotes removed, $var expanded, etc */ |
| set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*flag:*/ 0); |
| continue; |
| } |
| if (rword == RES_IN) { |
| continue; /* "for v IN list;..." - "in" has no cmds anyway */ |
| } |
| if (rword == RES_DONE) { |
| continue; /* "done" has no cmds too */ |
| } |
| #endif |
| #if ENABLE_HUSH_CASE |
| if (rword == RES_CASE) { |
| debug_printf_exec("CASE cond_code:%d\n", cond_code); |
| case_word = expand_string_to_string(pi->cmds->argv[0], |
| EXP_FLAG_ESC_GLOB_CHARS, /*unbackslash:*/ 1); |
| debug_printf_exec("CASE word1:'%s'\n", case_word); |
| //unbackslash(case_word); |
| //debug_printf_exec("CASE word2:'%s'\n", case_word); |
| continue; |
| } |
| if (rword == RES_MATCH) { |
| char **argv; |
| |
| debug_printf_exec("MATCH cond_code:%d\n", cond_code); |
| if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */ |
| break; |
| /* all prev words didn't match, does this one match? */ |
| argv = pi->cmds->argv; |
| while (*argv) { |
| char *pattern; |
| debug_printf_exec("expand_string_to_string('%s')\n", *argv); |
| pattern = expand_string_to_string(*argv, |
| EXP_FLAG_ESC_GLOB_CHARS, |
| /*unbackslash:*/ 0 |
| ); |
| /* TODO: which FNM_xxx flags to use? */ |
| cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0); |
| debug_printf_exec("fnmatch(pattern:'%s',str:'%s'):%d\n", |
| pattern, case_word, cond_code); |
| free(pattern); |
| if (cond_code == 0) { |
| /* match! we will execute this branch */ |
| free(case_word); |
| case_word = NULL; /* make future "word)" stop */ |
| break; |
| } |
| argv++; |
| } |
| continue; |
| } |
| if (rword == RES_CASE_BODY) { /* inside of a case branch */ |
| debug_printf_exec("CASE_BODY cond_code:%d\n", cond_code); |
| if (cond_code != 0) |
| continue; /* not matched yet, skip this pipe */ |
| } |
| if (rword == RES_ESAC) { |
| debug_printf_exec("ESAC cond_code:%d\n", cond_code); |
| if (case_word) { |
| /* "case" did not match anything: still set $? (to 0) */ |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| } |
| } |
| #endif |
| /* Just pressing <enter> in shell should check for jobs. |
| * OTOH, in non-interactive shell this is useless |
| * and only leads to extra job checks */ |
| if (pi->num_cmds == 0) { |
| if (G_interactive_fd) |
| goto check_jobs_and_continue; |
| continue; |
| } |
| |
| /* After analyzing all keywords and conditions, we decided |
| * to execute this pipe. NB: have to do checkjobs(NULL) |
| * after run_pipe to collect any background children, |
| * even if list execution is to be stopped. */ |
| debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds); |
| #if ENABLE_HUSH_LOOPS |
| G.flag_break_continue = 0; |
| #endif |
| rcode = r = G.o_opt[OPT_O_NOEXEC] ? 0 : run_pipe(pi); |
| /* NB: rcode is a smalluint, r is int */ |
| if (r != -1) { |
| /* We ran a builtin, function, or group. |
| * rcode is already known |
| * and we don't need to wait for anything. */ |
| debug_printf_exec(": builtin/func exitcode %d\n", rcode); |
| G.last_exitcode = rcode; |
| check_and_run_traps(); |
| #if ENABLE_HUSH_TRAP && ENABLE_HUSH_FUNCTIONS |
| rcode = G.last_exitcode; /* "return" in trap can change it, read back */ |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| /* Was it "break" or "continue"? */ |
| if (G.flag_break_continue) { |
| smallint fbc = G.flag_break_continue; |
| /* We might fall into outer *loop*, |
| * don't want to break it too */ |
| if (loop_top) { |
| G.depth_break_continue--; |
| if (G.depth_break_continue == 0) |
| G.flag_break_continue = 0; |
| /* else: e.g. "continue 2" should *break* once, *then* continue */ |
| } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */ |
| if (G.depth_break_continue != 0 || fbc == BC_BREAK) { |
| checkjobs(NULL, 0 /*(no pid to wait for)*/); |
| break; |
| } |
| /* "continue": simulate end of loop */ |
| rword = RES_DONE; |
| continue; |
| } |
| #endif |
| if (G_flag_return_in_progress == 1) { |
| checkjobs(NULL, 0 /*(no pid to wait for)*/); |
| break; |
| } |
| } else if (pi->followup == PIPE_BG) { |
| /* What does bash do with attempts to background builtins? */ |
| /* even bash 3.2 doesn't do that well with nested bg: |
| * try "{ { sleep 10; echo DEEP; } & echo HERE; } &". |
| * I'm NOT treating inner &'s as jobs */ |
| #if ENABLE_HUSH_JOB |
| if (G.run_list_level == 1) |
| insert_job_into_table(pi); |
| #endif |
| /* Last command's pid goes to $! */ |
| G.last_bg_pid = pi->cmds[pi->num_cmds - 1].pid; |
| G.last_bg_pid_exitcode = 0; |
| debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n"); |
| /* Check pi->pi_inverted? "! sleep 1 & echo $?": bash says 1. dash and ash say 0 */ |
| rcode = EXIT_SUCCESS; |
| goto check_traps; |
| } else { |
| #if ENABLE_HUSH_JOB |
| if (G.run_list_level == 1 && G_interactive_fd) { |
| /* Waits for completion, then fg's main shell */ |
| rcode = checkjobs_and_fg_shell(pi); |
| debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode); |
| goto check_traps; |
| } |
| #endif |
| /* This one just waits for completion */ |
| rcode = checkjobs(pi, 0 /*(no pid to wait for)*/); |
| debug_printf_exec(": checkjobs exitcode %d\n", rcode); |
| check_traps: |
| G.last_exitcode = rcode; |
| check_and_run_traps(); |
| #if ENABLE_HUSH_TRAP && ENABLE_HUSH_FUNCTIONS |
| rcode = G.last_exitcode; /* "return" in trap can change it, read back */ |
| #endif |
| } |
| |
| /* Handle "set -e" */ |
| if (rcode != 0 && G.o_opt[OPT_O_ERREXIT]) { |
| debug_printf_exec("ERREXIT:1 errexit_depth:%d\n", G.errexit_depth); |
| if (G.errexit_depth == 0) |
| hush_exit(rcode); |
| } |
| G.errexit_depth = sv_errexit_depth; |
| |
| /* Analyze how result affects subsequent commands */ |
| #if ENABLE_HUSH_IF |
| if (rword == RES_IF || rword == RES_ELIF) |
| cond_code = rcode; |
| #endif |
| check_jobs_and_continue: |
| checkjobs(NULL, 0 /*(no pid to wait for)*/); |
| dont_check_jobs_but_continue: ; |
| #if ENABLE_HUSH_LOOPS |
| /* Beware of "while false; true; do ..."! */ |
| if (pi->next |
| && (pi->next->res_word == RES_DO || pi->next->res_word == RES_DONE) |
| /* check for RES_DONE is needed for "while ...; do \n done" case */ |
| ) { |
| if (rword == RES_WHILE) { |
| if (rcode) { |
| /* "while false; do...done" - exitcode 0 */ |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n"); |
| break; |
| } |
| } |
| if (rword == RES_UNTIL) { |
| if (!rcode) { |
| debug_printf_exec(": until expr is true: breaking\n"); |
| break; |
| } |
| } |
| } |
| #endif |
| } /* for (pi) */ |
| |
| #if ENABLE_HUSH_JOB |
| G.run_list_level--; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| if (loop_top) |
| G.depth_of_loop--; |
| free(for_list); |
| #endif |
| #if ENABLE_HUSH_CASE |
| free(case_word); |
| #endif |
| debug_leave(); |
| debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode); |
| return rcode; |
| } |
| |
| /* Select which version we will use */ |
| static int run_and_free_list(struct pipe *pi) |
| { |
| int rcode = 0; |
| debug_printf_exec("run_and_free_list entered\n"); |
| if (!G.o_opt[OPT_O_NOEXEC]) { |
| debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds); |
| rcode = run_list(pi); |
| } |
| /* free_pipe_list has the side effect of clearing memory. |
| * In the long run that function can be merged with run_list, |
| * but doing that now would hobble the debugging effort. */ |
| free_pipe_list(pi); |
| debug_printf_exec("run_and_free_list return %d\n", rcode); |
| return rcode; |
| } |
| |
| |
| static void install_sighandlers(unsigned mask) |
| { |
| sighandler_t old_handler; |
| unsigned sig = 0; |
| while ((mask >>= 1) != 0) { |
| sig++; |
| if (!(mask & 1)) |
| continue; |
| old_handler = install_sighandler(sig, pick_sighandler(sig)); |
| /* POSIX allows shell to re-enable SIGCHLD |
| * even if it was SIG_IGN on entry. |
| * Therefore we skip IGN check for it: |
| */ |
| if (sig == SIGCHLD) |
| continue; |
| /* Interactive bash re-enables SIGHUP which is SIG_IGNed on entry. |
| * Try: |
| * trap '' hup; bash; echo RET # type "kill -hup $$", see SIGHUP having effect |
| * trap '' hup; bash -c 'kill -hup $$; echo ALIVE' # here SIGHUP is SIG_IGNed |
| */ |
| if (sig == SIGHUP && G_interactive_fd) |
| continue; |
| /* Unless one of the above signals, is it SIG_IGN? */ |
| if (old_handler == SIG_IGN) { |
| /* oops... restore back to IGN, and record this fact */ |
| install_sighandler(sig, old_handler); |
| #if ENABLE_HUSH_TRAP |
| if (!G_traps) |
| G_traps = xzalloc(sizeof(G_traps[0]) * NSIG); |
| free(G_traps[sig]); |
| G_traps[sig] = xzalloc(1); /* == xstrdup(""); */ |
| #endif |
| } |
| } |
| } |
| |
| /* Called a few times only (or even once if "sh -c") */ |
| static void install_special_sighandlers(void) |
| { |
| unsigned mask; |
| |
| /* Which signals are shell-special? */ |
| mask = (1 << SIGQUIT) | (1 << SIGCHLD); |
| if (G_interactive_fd) { |
| mask |= SPECIAL_INTERACTIVE_SIGS; |
| if (G_saved_tty_pgrp) /* we have ctty, job control sigs work */ |
| mask |= SPECIAL_JOBSTOP_SIGS; |
| } |
| /* Careful, do not re-install handlers we already installed */ |
| if (G.special_sig_mask != mask) { |
| unsigned diff = mask & ~G.special_sig_mask; |
| G.special_sig_mask = mask; |
| install_sighandlers(diff); |
| } |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* helper */ |
| /* Set handlers to restore tty pgrp and exit */ |
| static void install_fatal_sighandlers(void) |
| { |
| unsigned mask; |
| |
| /* We will restore tty pgrp on these signals */ |
| mask = 0 |
| /*+ (1 << SIGILL ) * HUSH_DEBUG*/ |
| /*+ (1 << SIGFPE ) * HUSH_DEBUG*/ |
| + (1 << SIGBUS ) * HUSH_DEBUG |
| + (1 << SIGSEGV) * HUSH_DEBUG |
| /*+ (1 << SIGTRAP) * HUSH_DEBUG*/ |
| + (1 << SIGABRT) |
| /* bash 3.2 seems to handle these just like 'fatal' ones */ |
| + (1 << SIGPIPE) |
| + (1 << SIGALRM) |
| /* if we are interactive, SIGHUP, SIGTERM and SIGINT are special sigs. |
| * if we aren't interactive... but in this case |
| * we never want to restore pgrp on exit, and this fn is not called |
| */ |
| /*+ (1 << SIGHUP )*/ |
| /*+ (1 << SIGTERM)*/ |
| /*+ (1 << SIGINT )*/ |
| ; |
| G_fatal_sig_mask = mask; |
| |
| install_sighandlers(mask); |
| } |
| #endif |
| |
| static int set_mode(int state, char mode, const char *o_opt) |
| { |
| int idx; |
| switch (mode) { |
| case 'n': |
| /* set -n has no effect in interactive shell */ |
| /* Try: while set -n; do echo $-; done */ |
| if (!G_interactive_fd) |
| G.o_opt[OPT_O_NOEXEC] = state; |
| break; |
| case 'x': |
| IF_HUSH_MODE_X(G_x_mode = state;) |
| IF_HUSH_MODE_X(if (G.x_mode_fd <= 0) G.x_mode_fd = dup_CLOEXEC(2, 10);) |
| break; |
| case 'e': |
| G.o_opt[OPT_O_ERREXIT] = state; |
| break; |
| case 'o': |
| if (!o_opt) { |
| /* "set -o" or "set +o" without parameter. |
| * in bash, set -o produces this output: |
| * pipefail off |
| * and set +o: |
| * set +o pipefail |
| * We always use the second form. |
| */ |
| const char *p = o_opt_strings; |
| idx = 0; |
| while (*p) { |
| printf("set %co %s\n", (G.o_opt[idx] ? '-' : '+'), p); |
| idx++; |
| p += strlen(p) + 1; |
| } |
| break; |
| } |
| idx = index_in_strings(o_opt_strings, o_opt); |
| if (idx >= 0) { |
| G.o_opt[idx] = state; |
| break; |
| } |
| /* fall through to error */ |
| default: |
| return EXIT_FAILURE; |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int hush_main(int argc, char **argv) |
| { |
| pid_t cached_getpid; |
| enum { |
| OPT_login = (1 << 0), |
| }; |
| unsigned flags; |
| #if !BB_MMU |
| unsigned builtin_argc = 0; |
| #endif |
| char **e; |
| struct variable *cur_var; |
| struct variable *shell_ver; |
| |
| INIT_G(); |
| if (EXIT_SUCCESS != 0) /* if EXIT_SUCCESS == 0, it is already done */ |
| G.last_exitcode = EXIT_SUCCESS; |
| #if ENABLE_HUSH_TRAP |
| # if ENABLE_HUSH_FUNCTIONS |
| G.return_exitcode = -1; |
| # endif |
| G.pre_trap_exitcode = -1; |
| #endif |
| |
| #if ENABLE_HUSH_FAST |
| G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */ |
| #endif |
| #if !BB_MMU |
| G.argv0_for_re_execing = argv[0]; |
| #endif |
| |
| cached_getpid = getpid(); /* for tcsetpgrp() during init */ |
| G.root_pid = cached_getpid; /* for $PID (NOMMU can override via -$HEXPID:HEXPPID:...) */ |
| G.root_ppid = getppid(); /* for $PPID (NOMMU can override) */ |
| |
| /* Deal with HUSH_VERSION */ |
| debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION"); |
| unsetenv("HUSH_VERSION"); /* in case it exists in initial env */ |
| shell_ver = xzalloc(sizeof(*shell_ver)); |
| shell_ver->flg_export = 1; |
| shell_ver->flg_read_only = 1; |
| /* Code which handles ${var<op>...} needs writable values for all variables, |
| * therefore we xstrdup: */ |
| shell_ver->varstr = xstrdup(hush_version_str); |
| |
| /* Create shell local variables from the values |
| * currently living in the environment */ |
| G.top_var = shell_ver; |
| cur_var = G.top_var; |
| e = environ; |
| if (e) while (*e) { |
| char *value = strchr(*e, '='); |
| if (value) { /* paranoia */ |
| cur_var->next = xzalloc(sizeof(*cur_var)); |
| cur_var = cur_var->next; |
| cur_var->varstr = *e; |
| cur_var->max_len = strlen(*e); |
| cur_var->flg_export = 1; |
| } |
| e++; |
| } |
| /* (Re)insert HUSH_VERSION into env (AFTER we scanned the env!) */ |
| debug_printf_env("putenv '%s'\n", shell_ver->varstr); |
| putenv(shell_ver->varstr); |
| |
| /* Export PWD */ |
| set_pwd_var(SETFLAG_EXPORT); |
| |
| #if BASH_HOSTNAME_VAR |
| /* Set (but not export) HOSTNAME unless already set */ |
| if (!get_local_var_value("HOSTNAME")) { |
| struct utsname uts; |
| uname(&uts); |
| set_local_var_from_halves("HOSTNAME", uts.nodename); |
| } |
| #endif |
| /* IFS is not inherited from the parent environment */ |
| set_local_var_from_halves("IFS", defifs); |
| |
| if (!get_local_var_value("PATH")) |
| set_local_var_from_halves("PATH", bb_default_root_path); |
| |
| /* PS1/PS2 are set later, if we determine that we are interactive */ |
| |
| /* bash also exports SHLVL and _, |
| * and sets (but doesn't export) the following variables: |
| * BASH=/bin/bash |
| * BASH_VERSINFO=([0]="3" [1]="2" [2]="0" [3]="1" [4]="release" [5]="i386-pc-linux-gnu") |
| * BASH_VERSION='3.2.0(1)-release' |
| * HOSTTYPE=i386 |
| * MACHTYPE=i386-pc-linux-gnu |
| * OSTYPE=linux-gnu |
| * PPID=<NNNNN> - we also do it elsewhere |
| * EUID=<NNNNN> |
| * UID=<NNNNN> |
| * GROUPS=() |
| * LINES=<NNN> |
| * COLUMNS=<NNN> |
| * BASH_ARGC=() |
| * BASH_ARGV=() |
| * BASH_LINENO=() |
| * BASH_SOURCE=() |
| * DIRSTACK=() |
| * PIPESTATUS=([0]="0") |
| * HISTFILE=/<xxx>/.bash_history |
| * HISTFILESIZE=500 |
| * HISTSIZE=500 |
| * MAILCHECK=60 |
| * PATH=/usr/gnu/bin:/usr/local/bin:/bin:/usr/bin:. |
| * SHELL=/bin/bash |
| * SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor |
| * TERM=dumb |
| * OPTERR=1 |
| * OPTIND=1 |
| * PS4='+ ' |
| */ |
| |
| #if NUM_SCRIPTS > 0 |
| if (argc < 0) { |
| char *script = get_script_content(-argc - 1); |
| G.global_argv = argv; |
| G.global_argc = string_array_len(argv); |
| //install_special_sighandlers(); - needed? |
| parse_and_run_string(script); |
| goto final_return; |
| } |
| #endif |
| |
| /* Initialize some more globals to non-zero values */ |
| die_func = restore_ttypgrp_and__exit; |
| |
| /* Shell is non-interactive at first. We need to call |
| * install_special_sighandlers() if we are going to execute "sh <script>", |
| * "sh -c <cmds>" or login shell's /etc/profile and friends. |
| * If we later decide that we are interactive, we run install_special_sighandlers() |
| * in order to intercept (more) signals. |
| */ |
| |
| /* Parse options */ |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */ |
| flags = (argv[0] && argv[0][0] == '-') ? OPT_login : 0; |
| while (1) { |
| int opt = getopt(argc, argv, "+" /* stop at 1st non-option */ |
| "cexinsl" |
| #if !BB_MMU |
| "<:$:R:V:" |
| # if ENABLE_HUSH_FUNCTIONS |
| "F:" |
| # endif |
| #endif |
| ); |
| if (opt <= 0) |
| break; |
| switch (opt) { |
| case 'c': |
| /* Note: -c is not an option with param! |
| * "hush -c -l SCRIPT" is valid. "hush -cSCRIPT" is not. |
| */ |
| G.opt_c = 1; |
| break; |
| case 'i': |
| /* Well, we cannot just declare interactiveness, |
| * we have to have some stuff (ctty, etc) */ |
| /* G_interactive_fd++; */ |
| //There are a few cases where bash -i -c 'SCRIPT' |
| //has visible effect (differs from bash -c 'SCRIPT'): |
| //it ignores TERM: |
| // bash -i -c 'kill $$; echo ALIVE' |
| // ALIVE |
| //it resets SIG_INGed HUP to SIG_DFL: |
| // trap '' hup; bash -i -c 'kill -hup $$; echo ALIVE' |
| // Hangup [the message is not printed by bash, it's the shell which started it] |
| //is talkative about jobs and exiting: |
| // bash -i -c 'sleep 1 & exit' |
| // [1] 16170 |
| // exit |
| //includes $ENV file (only if run as "sh"): |
| // echo last >/tmp/ENV; ENV=/tmp/ENV sh -i -c 'echo HERE' |
| // last: cannot open /var/log/wtmp: No such file or directory |
| // HERE |
| //(under "bash", it's the opposite: it runs $BASH_ENV file only *without* -i). |
| // |
| //ash -i -c 'sleep 3; sleep 3', on ^C, drops into a prompt instead of exiting |
| //(this may be a bug, bash does not do this). |
| //(ash -i -c 'sleep 3' won't show this, the last command gets auto-"exec"ed) |
| // |
| //None of the above feel like useful features people would rely on. |
| break; |
| case 's': |
| G.opt_s = 1; |
| break; |
| case 'l': |
| flags |= OPT_login; |
| break; |
| #if !BB_MMU |
| case '<': /* "big heredoc" support */ |
| full_write1_str(optarg); |
| _exit(0); |
| case '$': { |
| unsigned long long empty_trap_mask; |
| |
| G.root_pid = bb_strtou(optarg, &optarg, 16); |
| optarg++; |
| G.root_ppid = bb_strtou(optarg, &optarg, 16); |
| optarg++; |
| G.last_bg_pid = bb_strtou(optarg, &optarg, 16); |
| optarg++; |
| G.last_exitcode = bb_strtou(optarg, &optarg, 16); |
| optarg++; |
| builtin_argc = bb_strtou(optarg, &optarg, 16); |
| optarg++; |
| empty_trap_mask = bb_strtoull(optarg, &optarg, 16); |
| if (empty_trap_mask != 0) { |
| IF_HUSH_TRAP(int sig;) |
| install_special_sighandlers(); |
| # if ENABLE_HUSH_TRAP |
| G_traps = xzalloc(sizeof(G_traps[0]) * NSIG); |
| for (sig = 1; sig < NSIG; sig++) { |
| if (empty_trap_mask & (1LL << sig)) { |
| G_traps[sig] = xzalloc(1); /* == xstrdup(""); */ |
| install_sighandler(sig, SIG_IGN); |
| } |
| } |
| # endif |
| } |
| # if ENABLE_HUSH_LOOPS |
| optarg++; |
| G.depth_of_loop = bb_strtou(optarg, &optarg, 16); |
| # endif |
| /* Suppress "killed by signal" message, -$ hack is used |
| * for subshells: echo `sh -c 'kill -9 $$'` |
| * should be silent. |
| */ |
| IF_HUSH_JOB(G.run_list_level = 1;) |
| # if ENABLE_HUSH_FUNCTIONS |
| /* nommu uses re-exec trick for "... | func | ...", |
| * should allow "return". |
| * This accidentally allows returns in subshells. |
| */ |
| G_flag_return_in_progress = -1; |
| # endif |
| break; |
| } |
| case 'R': |
| case 'V': |
| set_local_var(xstrdup(optarg), opt == 'R' ? SETFLAG_MAKE_RO : 0); |
| break; |
| # if ENABLE_HUSH_FUNCTIONS |
| case 'F': { |
| struct function *funcp = new_function(optarg); |
| /* funcp->name is already set to optarg */ |
| /* funcp->body is set to NULL. It's a special case. */ |
| funcp->body_as_string = argv[optind]; |
| optind++; |
| break; |
| } |
| # endif |
| #endif |
| /*case '?': invalid option encountered (set_mode('?') will fail) */ |
| /*case 'n':*/ |
| /*case 'x':*/ |
| /*case 'e':*/ |
| default: |
| if (set_mode(1, opt, NULL) == 0) /* no error */ |
| break; |
| bb_show_usage(); |
| } |
| } /* option parsing loop */ |
| |
| /* Skip options. Try "hush -l": $1 should not be "-l"! */ |
| G.global_argc = argc - (optind - 1); |
| G.global_argv = argv + (optind - 1); |
| G.global_argv[0] = argv[0]; |
| |
| /* If we are login shell... */ |
| if (flags & OPT_login) { |
| const char *hp = NULL; |
| HFILE *input; |
| |
| debug_printf("sourcing /etc/profile\n"); |
| input = hfopen("/etc/profile"); |
| run_profile: |
| if (input != NULL) { |
| install_special_sighandlers(); |
| parse_and_run_file(input); |
| hfclose(input); |
| } |
| /* bash: after sourcing /etc/profile, |
| * tries to source (in the given order): |
| * ~/.bash_profile, ~/.bash_login, ~/.profile, |
| * stopping on first found. --noprofile turns this off. |
| * bash also sources ~/.bash_logout on exit. |
| * If called as sh, skips .bash_XXX files. |
| */ |
| if (!hp) { /* unless we looped on the "goto" already */ |
| hp = get_local_var_value("HOME"); |
| if (hp && hp[0]) { |
| debug_printf("sourcing ~/.profile\n"); |
| hp = concat_path_file(hp, ".profile"); |
| input = hfopen(hp); |
| free((char*)hp); |
| goto run_profile; |
| } |
| } |
| } |
| |
| /* -c takes effect *after* -l */ |
| if (G.opt_c) { |
| /* Possibilities: |
| * sh ... -c 'script' |
| * sh ... -c 'script' ARG0 [ARG1...] |
| * On NOMMU, if builtin_argc != 0, |
| * sh ... -c 'builtin' BARGV... "" ARG0 [ARG1...] |
| * "" needs to be replaced with NULL |
| * and BARGV vector fed to builtin function. |
| * Note: the form without ARG0 never happens: |
| * sh ... -c 'builtin' BARGV... "" |
| */ |
| char *script; |
| |
| install_special_sighandlers(); |
| |
| G.global_argc--; |
| G.global_argv++; |
| #if !BB_MMU |
| if (builtin_argc) { |
| /* -c 'builtin' [BARGV...] "" ARG0 [ARG1...] */ |
| const struct built_in_command *x; |
| x = find_builtin(G.global_argv[0]); |
| if (x) { /* paranoia */ |
| argv = G.global_argv; |
| G.global_argc -= builtin_argc + 1; /* skip [BARGV...] "" */ |
| G.global_argv += builtin_argc + 1; |
| G.global_argv[-1] = NULL; /* replace "" */ |
| G.last_exitcode = x->b_function(argv); |
| } |
| goto final_return; |
| } |
| #endif |
| |
| script = G.global_argv[0]; |
| if (!script) |
| bb_error_msg_and_die(bb_msg_requires_arg, "-c"); |
| if (!G.global_argv[1]) { |
| /* -c 'script' (no params): prevent empty $0 */ |
| G.global_argv[0] = argv[0]; |
| } else { /* else -c 'script' ARG0 [ARG1...]: $0 is ARG0 */ |
| G.global_argc--; |
| G.global_argv++; |
| } |
| parse_and_run_string(script); |
| goto final_return; |
| } |
| |
| /* -s is: hush -s ARGV1 ARGV2 (no SCRIPT) */ |
| if (!G.opt_s && G.global_argv[1]) { |
| HFILE *input; |
| /* |
| * "bash <script>" (which is never interactive (unless -i?)) |
| * sources $BASH_ENV here (without scanning $PATH). |
| * If called as sh, does the same but with $ENV. |
| * Also NB, per POSIX, $ENV should undergo parameter expansion. |
| */ |
| G.global_argc--; |
| G.global_argv++; |
| debug_printf("running script '%s'\n", G.global_argv[0]); |
| xfunc_error_retval = 127; /* for "hush /does/not/exist" case */ |
| input = hfopen(G.global_argv[0]); |
| if (!input) { |
| bb_simple_perror_msg_and_die(G.global_argv[0]); |
| } |
| xfunc_error_retval = 1; |
| install_special_sighandlers(); |
| parse_and_run_file(input); |
| #if ENABLE_FEATURE_CLEAN_UP |
| hfclose(input); |
| #endif |
| goto final_return; |
| } |
| /* "implicit" -s: bare interactive hush shows 's' in $- */ |
| G.opt_s = 1; |
| |
| /* Up to here, shell was non-interactive. Now it may become one. |
| * NB: don't forget to (re)run install_special_sighandlers() as needed. |
| */ |
| |
| /* A shell is interactive if the '-i' flag was given, |
| * or if all of the following conditions are met: |
| * no -c command |
| * no arguments remaining or the -s flag given |
| * standard input is a terminal |
| * standard output is a terminal |
| * Refer to Posix.2, the description of the 'sh' utility. |
| */ |
| #if ENABLE_HUSH_JOB |
| if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) { |
| G_saved_tty_pgrp = tcgetpgrp(STDIN_FILENO); |
| debug_printf("saved_tty_pgrp:%d\n", G_saved_tty_pgrp); |
| if (G_saved_tty_pgrp < 0) |
| G_saved_tty_pgrp = 0; |
| |
| /* try to dup stdin to high fd#, >= 255 */ |
| G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, 254); |
| if (G_interactive_fd < 0) { |
| /* try to dup to any fd */ |
| G_interactive_fd = dup(STDIN_FILENO); |
| if (G_interactive_fd < 0) { |
| /* give up */ |
| G_interactive_fd = 0; |
| G_saved_tty_pgrp = 0; |
| } |
| } |
| } |
| debug_printf("interactive_fd:%d\n", G_interactive_fd); |
| if (G_interactive_fd) { |
| close_on_exec_on(G_interactive_fd); |
| |
| if (G_saved_tty_pgrp) { |
| /* If we were run as 'hush &', sleep until we are |
| * in the foreground (tty pgrp == our pgrp). |
| * If we get started under a job aware app (like bash), |
| * make sure we are now in charge so we don't fight over |
| * who gets the foreground */ |
| while (1) { |
| pid_t shell_pgrp = getpgrp(); |
| G_saved_tty_pgrp = tcgetpgrp(G_interactive_fd); |
| if (G_saved_tty_pgrp == shell_pgrp) |
| break; |
| /* send TTIN to ourself (should stop us) */ |
| kill(- shell_pgrp, SIGTTIN); |
| } |
| } |
| |
| /* Install more signal handlers */ |
| install_special_sighandlers(); |
| |
| if (G_saved_tty_pgrp) { |
| /* Set other signals to restore saved_tty_pgrp */ |
| install_fatal_sighandlers(); |
| /* Put ourselves in our own process group |
| * (bash, too, does this only if ctty is available) */ |
| bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */ |
| /* Grab control of the terminal */ |
| tcsetpgrp(G_interactive_fd, cached_getpid); |
| } |
| enable_restore_tty_pgrp_on_exit(); |
| |
| # if ENABLE_FEATURE_EDITING |
| G.line_input_state = new_line_input_t(FOR_SHELL); |
| # if EDITING_HAS_get_exe_name |
| G.line_input_state->get_exe_name = get_builtin_name; |
| # endif |
| # endif |
| # if ENABLE_HUSH_SAVEHISTORY && MAX_HISTORY > 0 |
| { |
| const char *hp = get_local_var_value("HISTFILE"); |
| if (!hp) { |
| hp = get_local_var_value("HOME"); |
| if (hp) |
| hp = concat_path_file(hp, ".hush_history"); |
| } else { |
| hp = xstrdup(hp); |
| } |
| if (hp) { |
| G.line_input_state->hist_file = hp; |
| //set_local_var(xasprintf("HISTFILE=%s", ...)); |
| } |
| # if ENABLE_FEATURE_SH_HISTFILESIZE |
| hp = get_local_var_value("HISTFILESIZE"); |
| G.line_input_state->max_history = size_from_HISTFILESIZE(hp); |
| # endif |
| } |
| # endif |
| } else { |
| install_special_sighandlers(); |
| } |
| #elif ENABLE_HUSH_INTERACTIVE |
| /* No job control compiled in, only prompt/line editing */ |
| if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) { |
| G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, 254); |
| if (G_interactive_fd < 0) { |
| /* try to dup to any fd */ |
| G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, -1); |
| if (G_interactive_fd < 0) |
| /* give up */ |
| G_interactive_fd = 0; |
| } |
| } |
| if (G_interactive_fd) { |
| close_on_exec_on(G_interactive_fd); |
| } |
| install_special_sighandlers(); |
| #else |
| /* We have interactiveness code disabled */ |
| install_special_sighandlers(); |
| #endif |
| /* bash: |
| * if interactive but not a login shell, sources ~/.bashrc |
| * (--norc turns this off, --rcfile <file> overrides) |
| */ |
| |
| if (G_interactive_fd) { |
| #if ENABLE_HUSH_INTERACTIVE && ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| /* Set (but not export) PS1/2 unless already set */ |
| if (!get_local_var_value("PS1")) |
| set_local_var_from_halves("PS1", "\\w \\$ "); |
| if (!get_local_var_value("PS2")) |
| set_local_var_from_halves("PS2", "> "); |
| #endif |
| if (!ENABLE_FEATURE_SH_EXTRA_QUIET) { |
| /* note: ash and hush share this string */ |
| printf("\n\n%s %s\n" |
| IF_HUSH_HELP("Enter 'help' for a list of built-in commands.\n") |
| "\n", |
| bb_banner, |
| "hush - the humble shell" |
| ); |
| } |
| } |
| |
| parse_and_run_file(hfopen(NULL)); /* stdin */ |
| |
| final_return: |
| hush_exit(G.last_exitcode); |
| } |
| |
| |
| /* |
| * Built-ins |
| */ |
| static int FAST_FUNC builtin_true(char **argv UNUSED_PARAM) |
| { |
| return 0; |
| } |
| |
| #if ENABLE_HUSH_TEST || ENABLE_HUSH_ECHO || ENABLE_HUSH_PRINTF || ENABLE_HUSH_KILL |
| static NOINLINE int run_applet_main(char **argv, int (*applet_main_func)(int argc, char **argv)) |
| { |
| int argc = string_array_len(argv); |
| return applet_main_func(argc, argv); |
| } |
| #endif |
| #if ENABLE_HUSH_TEST || BASH_TEST2 |
| static int FAST_FUNC builtin_test(char **argv) |
| { |
| return run_applet_main(argv, test_main); |
| } |
| #endif |
| #if ENABLE_HUSH_ECHO |
| static int FAST_FUNC builtin_echo(char **argv) |
| { |
| return run_applet_main(argv, echo_main); |
| } |
| #endif |
| #if ENABLE_HUSH_PRINTF |
| static int FAST_FUNC builtin_printf(char **argv) |
| { |
| return run_applet_main(argv, printf_main); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_HELP |
| static int FAST_FUNC builtin_help(char **argv UNUSED_PARAM) |
| { |
| const struct built_in_command *x; |
| |
| printf( |
| "Built-in commands:\n" |
| "------------------\n"); |
| for (x = bltins1; x != &bltins1[ARRAY_SIZE(bltins1)]; x++) { |
| if (x->b_descr) |
| printf("%-10s%s\n", x->b_cmd, x->b_descr); |
| } |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if MAX_HISTORY && ENABLE_FEATURE_EDITING |
| static int FAST_FUNC builtin_history(char **argv UNUSED_PARAM) |
| { |
| show_history(G.line_input_state); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| static char **skip_dash_dash(char **argv) |
| { |
| argv++; |
| if (argv[0] && argv[0][0] == '-' && argv[0][1] == '-' && argv[0][2] == '\0') |
| argv++; |
| return argv; |
| } |
| |
| static int FAST_FUNC builtin_cd(char **argv) |
| { |
| const char *newdir; |
| |
| argv = skip_dash_dash(argv); |
| newdir = argv[0]; |
| if (newdir == NULL) { |
| /* bash does nothing (exitcode 0) if HOME is ""; if it's unset, |
| * bash says "bash: cd: HOME not set" and does nothing |
| * (exitcode 1) |
| */ |
| const char *home = get_local_var_value("HOME"); |
| newdir = home ? home : "/"; |
| } |
| if (chdir(newdir)) { |
| /* Mimic bash message exactly */ |
| bb_perror_msg("cd: %s", newdir); |
| return EXIT_FAILURE; |
| } |
| /* Read current dir (get_cwd(1) is inside) and set PWD. |
| * Note: do not enforce exporting. If PWD was unset or unexported, |
| * set it again, but do not export. bash does the same. |
| */ |
| set_pwd_var(/*flag:*/ 0); |
| return EXIT_SUCCESS; |
| } |
| |
| static int FAST_FUNC builtin_pwd(char **argv UNUSED_PARAM) |
| { |
| puts(get_cwd(0)); |
| return EXIT_SUCCESS; |
| } |
| |
| static int FAST_FUNC builtin_eval(char **argv) |
| { |
| argv = skip_dash_dash(argv); |
| |
| if (!argv[0]) |
| return EXIT_SUCCESS; |
| |
| IF_HUSH_MODE_X(G.x_mode_depth++;) |
| //bb_error_msg("%s: ++x_mode_depth=%d", __func__, G.x_mode_depth); |
| if (!argv[1]) { |
| /* bash: |
| * eval "echo Hi; done" ("done" is syntax error): |
| * "echo Hi" will not execute too. |
| */ |
| parse_and_run_string(argv[0]); |
| } else { |
| /* "The eval utility shall construct a command by |
| * concatenating arguments together, separating |
| * each with a <space> character." |
| */ |
| char *str, *p; |
| unsigned len = 0; |
| char **pp = argv; |
| do |
| len += strlen(*pp) + 1; |
| while (*++pp); |
| str = p = xmalloc(len); |
| pp = argv; |
| for (;;) { |
| p = stpcpy(p, *pp); |
| pp++; |
| if (!*pp) |
| break; |
| *p++ = ' '; |
| } |
| parse_and_run_string(str); |
| free(str); |
| } |
| IF_HUSH_MODE_X(G.x_mode_depth--;) |
| //bb_error_msg("%s: --x_mode_depth=%d", __func__, G.x_mode_depth); |
| return G.last_exitcode; |
| } |
| |
| static int FAST_FUNC builtin_exec(char **argv) |
| { |
| argv = skip_dash_dash(argv); |
| if (argv[0] == NULL) |
| return EXIT_SUCCESS; /* bash does this */ |
| |
| /* Careful: we can end up here after [v]fork. Do not restore |
| * tty pgrp then, only top-level shell process does that */ |
| if (G_saved_tty_pgrp && getpid() == G.root_pid) |
| tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp); |
| |
| /* Saved-redirect fds, script fds and G_interactive_fd are still |
| * open here. However, they are all CLOEXEC, and execv below |
| * closes them. Try interactive "exec ls -l /proc/self/fd", |
| * it should show no extra open fds in the "ls" process. |
| * If we'd try to run builtins/NOEXECs, this would need improving. |
| */ |
| //close_saved_fds_and_FILE_fds(); |
| |
| /* TODO: if exec fails, bash does NOT exit! We do. |
| * We'll need to undo trap cleanup (it's inside execvp_or_die) |
| * and tcsetpgrp, and this is inherently racy. |
| */ |
| execvp_or_die(argv); |
| } |
| |
| static int FAST_FUNC builtin_exit(char **argv) |
| { |
| debug_printf_exec("%s()\n", __func__); |
| |
| /* interactive bash: |
| * # trap "echo EEE" EXIT |
| * # exit |
| * exit |
| * There are stopped jobs. |
| * (if there are _stopped_ jobs, running ones don't count) |
| * # exit |
| * exit |
| * EEE (then bash exits) |
| * |
| * TODO: we can use G.exiting = -1 as indicator "last cmd was exit" |
| */ |
| |
| /* note: EXIT trap is run by hush_exit */ |
| argv = skip_dash_dash(argv); |
| if (argv[0] == NULL) { |
| #if ENABLE_HUSH_TRAP |
| if (G.pre_trap_exitcode >= 0) /* "exit" in trap uses $? from before the trap */ |
| hush_exit(G.pre_trap_exitcode); |
| #endif |
| hush_exit(G.last_exitcode); |
| } |
| /* mimic bash: exit 123abc == exit 255 + error msg */ |
| xfunc_error_retval = 255; |
| /* bash: exit -2 == exit 254, no error msg */ |
| hush_exit(xatoi(argv[0]) & 0xff); |
| } |
| |
| #if ENABLE_HUSH_TYPE |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/type.html */ |
| static int FAST_FUNC builtin_type(char **argv) |
| { |
| int ret = EXIT_SUCCESS; |
| |
| while (*++argv) { |
| const char *type; |
| char *path = NULL; |
| |
| if (0) {} /* make conditional compile easier below */ |
| /*else if (find_alias(*argv)) |
| type = "an alias";*/ |
| # if ENABLE_HUSH_FUNCTIONS |
| else if (find_function(*argv)) |
| type = "a function"; |
| # endif |
| else if (find_builtin(*argv)) |
| type = "a shell builtin"; |
| else if ((path = find_in_path(*argv)) != NULL) |
| type = path; |
| else { |
| bb_error_msg("type: %s: not found", *argv); |
| ret = EXIT_FAILURE; |
| continue; |
| } |
| |
| printf("%s is %s\n", *argv, type); |
| free(path); |
| } |
| |
| return ret; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_READ |
| /* Interruptibility of read builtin in bash |
| * (tested on bash-4.2.8 by sending signals (not by ^C)): |
| * |
| * Empty trap makes read ignore corresponding signal, for any signal. |
| * |
| * SIGINT: |
| * - terminates non-interactive shell; |
| * - interrupts read in interactive shell; |
| * if it has non-empty trap: |
| * - executes trap and returns to command prompt in interactive shell; |
| * - executes trap and returns to read in non-interactive shell; |
| * SIGTERM: |
| * - is ignored (does not interrupt) read in interactive shell; |
| * - terminates non-interactive shell; |
| * if it has non-empty trap: |
| * - executes trap and returns to read; |
| * SIGHUP: |
| * - terminates shell (regardless of interactivity); |
| * if it has non-empty trap: |
| * - executes trap and returns to read; |
| * SIGCHLD from children: |
| * - does not interrupt read regardless of interactivity: |
| * try: sleep 1 & read x; echo $x |
| */ |
| static int FAST_FUNC builtin_read(char **argv) |
| { |
| const char *r; |
| struct builtin_read_params params; |
| |
| memset(¶ms, 0, sizeof(params)); |
| |
| /* "!": do not abort on errors. |
| * Option string must start with "sr" to match BUILTIN_READ_xxx |
| */ |
| params.read_flags = getopt32(argv, |
| # if BASH_READ_D |
| IF_NOT_HUSH_BASH_COMPAT("^") |
| "!srn:p:t:u:d:" IF_NOT_HUSH_BASH_COMPAT("\0" "-1"/*min 1 arg*/), |
| ¶ms.opt_n, ¶ms.opt_p, ¶ms.opt_t, ¶ms.opt_u, ¶ms.opt_d |
| # else |
| IF_NOT_HUSH_BASH_COMPAT("^") |
| "!srn:p:t:u:" IF_NOT_HUSH_BASH_COMPAT("\0" "-1"/*min 1 arg*/), |
| ¶ms.opt_n, ¶ms.opt_p, ¶ms.opt_t, ¶ms.opt_u |
| # endif |
| //TODO: print "read: need variable name" |
| //for the case of !BASH "read" with no args (now it fails silently) |
| //(or maybe extend getopt32() to emit a message if "-1" fails) |
| ); |
| if ((uint32_t)params.read_flags == (uint32_t)-1) |
| return EXIT_FAILURE; |
| argv += optind; |
| params.argv = argv; |
| params.setvar = set_local_var_from_halves; |
| params.ifs = get_local_var_value("IFS"); /* can be NULL */ |
| |
| again: |
| r = shell_builtin_read(¶ms); |
| |
| if ((uintptr_t)r == 1 && errno == EINTR) { |
| unsigned sig = check_and_run_traps(); |
| if (sig != SIGINT) |
| goto again; |
| } |
| |
| if ((uintptr_t)r > 1) { |
| bb_simple_error_msg(r); |
| r = (char*)(uintptr_t)1; |
| } |
| |
| return (uintptr_t)r; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_UMASK |
| static int FAST_FUNC builtin_umask(char **argv) |
| { |
| int rc; |
| mode_t mask; |
| |
| rc = 1; |
| mask = umask(0); |
| argv = skip_dash_dash(argv); |
| if (argv[0]) { |
| mode_t old_mask = mask; |
| |
| /* numeric umasks are taken as-is */ |
| /* symbolic umasks are inverted: "umask a=rx" calls umask(222) */ |
| if (!isdigit(argv[0][0])) |
| mask ^= 0777; |
| mask = bb_parse_mode(argv[0], mask); |
| if (!isdigit(argv[0][0])) |
| mask ^= 0777; |
| if ((unsigned)mask > 0777) { |
| mask = old_mask; |
| /* bash messages: |
| * bash: umask: 'q': invalid symbolic mode operator |
| * bash: umask: 999: octal number out of range |
| */ |
| bb_error_msg("%s: invalid mode '%s'", "umask", argv[0]); |
| rc = 0; |
| } |
| } else { |
| /* Mimic bash */ |
| printf("%04o\n", (unsigned) mask); |
| /* fall through and restore mask which we set to 0 */ |
| } |
| umask(mask); |
| |
| return !rc; /* rc != 0 - success */ |
| } |
| #endif |
| |
| #if ENABLE_HUSH_EXPORT || ENABLE_HUSH_TRAP |
| static void print_escaped(const char *s) |
| { |
| if (*s == '\'') |
| goto squote; |
| do { |
| const char *p = strchrnul(s, '\''); |
| /* print 'xxxx', possibly just '' */ |
| printf("'%.*s'", (int)(p - s), s); |
| if (*p == '\0') |
| break; |
| s = p; |
| squote: |
| /* s points to '; print "'''...'''" */ |
| putchar('"'); |
| do putchar('\''); while (*++s == '\''); |
| putchar('"'); |
| } while (*s); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_EXPORT || ENABLE_HUSH_LOCAL || ENABLE_HUSH_READONLY |
| static int helper_export_local(char **argv, unsigned flags) |
| { |
| do { |
| char *name = *argv; |
| const char *name_end = endofname(name); |
| |
| if (*name_end == '\0') { |
| struct variable *var, **vpp; |
| |
| vpp = get_ptr_to_local_var(name, name_end - name); |
| var = vpp ? *vpp : NULL; |
| |
| if (flags & SETFLAG_UNEXPORT) { |
| /* export -n NAME (without =VALUE) */ |
| if (var) { |
| var->flg_export = 0; |
| debug_printf_env("%s: unsetenv '%s'\n", __func__, name); |
| unsetenv(name); |
| } /* else: export -n NOT_EXISTING_VAR: no-op */ |
| continue; |
| } |
| if (flags & SETFLAG_EXPORT) { |
| /* export NAME (without =VALUE) */ |
| if (var) { |
| var->flg_export = 1; |
| debug_printf_env("%s: putenv '%s'\n", __func__, var->varstr); |
| putenv(var->varstr); |
| continue; |
| } |
| } |
| if (flags & SETFLAG_MAKE_RO) { |
| /* readonly NAME (without =VALUE) */ |
| if (var) { |
| var->flg_read_only = 1; |
| continue; |
| } |
| } |
| # if ENABLE_HUSH_LOCAL |
| /* Is this "local" bltin? */ |
| if (!(flags & (SETFLAG_EXPORT|SETFLAG_UNEXPORT|SETFLAG_MAKE_RO))) { |
| unsigned lvl = flags >> SETFLAG_VARLVL_SHIFT; |
| if (var && var->var_nest_level == lvl) { |
| /* "local x=abc; ...; local x" - ignore second local decl */ |
| continue; |
| } |
| } |
| # endif |
| /* Exporting non-existing variable. |
| * bash does not put it in environment, |
| * but remembers that it is exported, |
| * and does put it in env when it is set later. |
| * We just set it to "" and export. |
| */ |
| /* Or, it's "local NAME" (without =VALUE). |
| * bash sets the value to "". |
| */ |
| /* Or, it's "readonly NAME" (without =VALUE). |
| * bash remembers NAME and disallows its creation |
| * in the future. |
| */ |
| name = xasprintf("%s=", name); |
| } else { |
| if (*name_end != '=') { |
| bb_error_msg("'%s': bad variable name", name); |
| /* do not parse following argv[]s: */ |
| return 1; |
| } |
| /* (Un)exporting/making local NAME=VALUE */ |
| name = xstrdup(name); |
| /* Testcase: export PS1='\w \$ ' */ |
| unbackslash(name); |
| } |
| debug_printf_env("%s: set_local_var('%s')\n", __func__, name); |
| if (set_local_var(name, flags)) |
| return EXIT_FAILURE; |
| } while (*++argv); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_EXPORT |
| static int FAST_FUNC builtin_export(char **argv) |
| { |
| unsigned opt_unexport; |
| |
| # if ENABLE_HUSH_EXPORT_N |
| /* "!": do not abort on errors */ |
| opt_unexport = getopt32(argv, "!n"); |
| if (opt_unexport == (uint32_t)-1) |
| return EXIT_FAILURE; |
| argv += optind; |
| # else |
| opt_unexport = 0; |
| argv++; |
| # endif |
| |
| if (argv[0] == NULL) { |
| char **e = environ; |
| if (e) { |
| while (*e) { |
| # if 0 |
| puts(*e++); |
| # else |
| /* ash emits: export VAR='VAL' |
| * bash: declare -x VAR="VAL" |
| * we follow ash example */ |
| const char *s = *e++; |
| const char *p = strchr(s, '='); |
| |
| if (!p) /* wtf? take next variable */ |
| continue; |
| /* export var= */ |
| printf("export %.*s", (int)(p - s) + 1, s); |
| print_escaped(p + 1); |
| putchar('\n'); |
| # endif |
| } |
| /*fflush_all(); - done after each builtin anyway */ |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| return helper_export_local(argv, opt_unexport ? SETFLAG_UNEXPORT : SETFLAG_EXPORT); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_LOCAL |
| static int FAST_FUNC builtin_local(char **argv) |
| { |
| if (G.func_nest_level == 0) { |
| bb_error_msg("%s: not in a function", argv[0]); |
| return EXIT_FAILURE; /* bash compat */ |
| } |
| argv++; |
| /* Since all builtins run in a nested variable level, |
| * need to use level - 1 here. Or else the variable will be removed at once |
| * after builtin returns. |
| */ |
| return helper_export_local(argv, (G.var_nest_level - 1) << SETFLAG_VARLVL_SHIFT); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_READONLY |
| static int FAST_FUNC builtin_readonly(char **argv) |
| { |
| argv++; |
| if (*argv == NULL) { |
| /* bash: readonly [-p]: list all readonly VARs |
| * (-p has no effect in bash) |
| */ |
| struct variable *e; |
| for (e = G.top_var; e; e = e->next) { |
| if (e->flg_read_only) { |
| //TODO: quote value: readonly VAR='VAL' |
| printf("readonly %s\n", e->varstr); |
| } |
| } |
| return EXIT_SUCCESS; |
| } |
| return helper_export_local(argv, SETFLAG_MAKE_RO); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_UNSET |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */ |
| static int FAST_FUNC builtin_unset(char **argv) |
| { |
| int ret; |
| unsigned opts; |
| |
| /* "!": do not abort on errors */ |
| /* "+": stop at 1st non-option */ |
| opts = getopt32(argv, "!+vf"); |
| if (opts == (unsigned)-1) |
| return EXIT_FAILURE; |
| if (opts == 3) { |
| bb_simple_error_msg("unset: -v and -f are exclusive"); |
| return EXIT_FAILURE; |
| } |
| argv += optind; |
| |
| ret = EXIT_SUCCESS; |
| while (*argv) { |
| if (!(opts & 2)) { /* not -f */ |
| if (unset_local_var(*argv)) { |
| /* unset <nonexistent_var> doesn't fail. |
| * Error is when one tries to unset RO var. |
| * Message was printed by unset_local_var. */ |
| ret = EXIT_FAILURE; |
| } |
| } |
| # if ENABLE_HUSH_FUNCTIONS |
| else { |
| unset_func(*argv); |
| } |
| # endif |
| argv++; |
| } |
| return ret; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_SET |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set |
| * built-in 'set' handler |
| * SUSv3 says: |
| * set [-abCefhmnuvx] [-o option] [argument...] |
| * set [+abCefhmnuvx] [+o option] [argument...] |
| * set -- [argument...] |
| * set -o |
| * set +o |
| * Implementations shall support the options in both their hyphen and |
| * plus-sign forms. These options can also be specified as options to sh. |
| * Examples: |
| * Write out all variables and their values: set |
| * Set $1, $2, and $3 and set "$#" to 3: set c a b |
| * Turn on the -x and -v options: set -xv |
| * Unset all positional parameters: set -- |
| * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x" |
| * Set the positional parameters to the expansion of x, even if x expands |
| * with a leading '-' or '+': set -- $x |
| * |
| * So far, we only support "set -- [argument...]" and some of the short names. |
| */ |
| static int FAST_FUNC builtin_set(char **argv) |
| { |
| int n; |
| char **pp, **g_argv; |
| char *arg = *++argv; |
| |
| if (arg == NULL) { |
| struct variable *e; |
| for (e = G.top_var; e; e = e->next) |
| puts(e->varstr); |
| return EXIT_SUCCESS; |
| } |
| |
| do { |
| if (strcmp(arg, "--") == 0) { |
| ++argv; |
| goto set_argv; |
| } |
| if (arg[0] != '+' && arg[0] != '-') |
| break; |
| for (n = 1; arg[n]; ++n) { |
| if (set_mode((arg[0] == '-'), arg[n], argv[1])) { |
| bb_error_msg("%s: %s: invalid option", "set", arg); |
| return EXIT_FAILURE; |
| } |
| if (arg[n] == 'o' && argv[1]) |
| argv++; |
| } |
| } while ((arg = *++argv) != NULL); |
| /* Now argv[0] is 1st argument */ |
| |
| if (arg == NULL) |
| return EXIT_SUCCESS; |
| set_argv: |
| |
| /* NB: G.global_argv[0] ($0) is never freed/changed */ |
| g_argv = G.global_argv; |
| if (G.global_args_malloced) { |
| pp = g_argv; |
| while (*++pp) |
| free(*pp); |
| g_argv[1] = NULL; |
| } else { |
| G.global_args_malloced = 1; |
| pp = xzalloc(sizeof(pp[0]) * 2); |
| pp[0] = g_argv[0]; /* retain $0 */ |
| g_argv = pp; |
| } |
| /* This realloc's G.global_argv */ |
| G.global_argv = pp = add_strings_to_strings(g_argv, argv, /*dup:*/ 1); |
| |
| G.global_argc = 1 + string_array_len(pp + 1); |
| |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| static int FAST_FUNC builtin_shift(char **argv) |
| { |
| int n = 1; |
| argv = skip_dash_dash(argv); |
| if (argv[0]) { |
| n = bb_strtou(argv[0], NULL, 10); |
| if (errno || n < 0) { |
| /* shared string with ash.c */ |
| bb_error_msg("Illegal number: %s", argv[0]); |
| /* |
| * ash aborts in this case. |
| * bash prints error message and set $? to 1. |
| * Interestingly, for "shift 99999" bash does not |
| * print error message, but does set $? to 1 |
| * (and does no shifting at all). |
| */ |
| } |
| } |
| if (n >= 0 && n < G.global_argc) { |
| if (G_global_args_malloced) { |
| int m = 1; |
| while (m <= n) |
| free(G.global_argv[m++]); |
| } |
| G.global_argc -= n; |
| memmove(&G.global_argv[1], &G.global_argv[n+1], |
| G.global_argc * sizeof(G.global_argv[0])); |
| return EXIT_SUCCESS; |
| } |
| return EXIT_FAILURE; |
| } |
| |
| #if ENABLE_HUSH_GETOPTS |
| static int FAST_FUNC builtin_getopts(char **argv) |
| { |
| /* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/getopts.html |
| |
| TODO: |
| If a required argument is not found, and getopts is not silent, |
| a question mark (?) is placed in VAR, OPTARG is unset, and a |
| diagnostic message is printed. If getopts is silent, then a |
| colon (:) is placed in VAR and OPTARG is set to the option |
| character found. |
| |
| Test that VAR is a valid variable name? |
| |
| "Whenever the shell is invoked, OPTIND shall be initialized to 1" |
| */ |
| char cbuf[2]; |
| const char *cp, *optstring, *var; |
| int c, n, exitcode, my_opterr; |
| unsigned count; |
| |
| optstring = *++argv; |
| if (!optstring || !(var = *++argv)) { |
| bb_simple_error_msg("usage: getopts OPTSTRING VAR [ARGS]"); |
| return EXIT_FAILURE; |
| } |
| |
| if (argv[1]) |
| argv[0] = G.global_argv[0]; /* for error messages in getopt() */ |
| else |
| argv = G.global_argv; |
| cbuf[1] = '\0'; |
| |
| my_opterr = 0; |
| if (optstring[0] != ':') { |
| cp = get_local_var_value("OPTERR"); |
| /* 0 if "OPTERR=0", 1 otherwise */ |
| my_opterr = (!cp || NOT_LONE_CHAR(cp, '0')); |
| } |
| |
| /* getopts stops on first non-option. Add "+" to force that */ |
| /*if (optstring[0] != '+')*/ { |
| char *s = alloca(strlen(optstring) + 2); |
| sprintf(s, "+%s", optstring); |
| optstring = s; |
| } |
| |
| /* Naively, now we should just |
| * cp = get_local_var_value("OPTIND"); |
| * optind = cp ? atoi(cp) : 0; |
| * optarg = NULL; |
| * opterr = my_opterr; |
| * c = getopt(string_array_len(argv), argv, optstring); |
| * and be done? Not so fast... |
| * Unlike normal getopt() usage in C programs, here |
| * each successive call will (usually) have the same argv[] CONTENTS, |
| * but not the ADDRESSES. Worse yet, it's possible that between |
| * invocations of "getopts", there will be calls to shell builtins |
| * which use getopt() internally. Example: |
| * while getopts "abc" RES -a -bc -abc de; do |
| * unset -ff func |
| * done |
| * This would not work correctly: getopt() call inside "unset" |
| * modifies internal libc state which is tracking position in |
| * multi-option strings ("-abc"). At best, it can skip options |
| * or return the same option infinitely. With glibc implementation |
| * of getopt(), it would use outright invalid pointers and return |
| * garbage even _without_ "unset" mangling internal state. |
| * |
| * We resort to resetting getopt() state and calling it N times, |
| * until we get Nth result (or failure). |
| * (N == G.getopt_count is reset to 0 whenever OPTIND is [un]set). |
| */ |
| GETOPT_RESET(); |
| count = 0; |
| n = string_array_len(argv); |
| do { |
| optarg = NULL; |
| opterr = (count < G.getopt_count) ? 0 : my_opterr; |
| c = getopt(n, argv, optstring); |
| if (c < 0) |
| break; |
| count++; |
| } while (count <= G.getopt_count); |
| |
| /* Set OPTIND. Prevent resetting of the magic counter! */ |
| set_local_var_from_halves("OPTIND", utoa(optind)); |
| G.getopt_count = count; /* "next time, give me N+1'th result" */ |
| GETOPT_RESET(); /* just in case */ |
| |
| /* Set OPTARG */ |
| /* Always set or unset, never left as-is, even on exit/error: |
| * "If no option was found, or if the option that was found |
| * does not have an option-argument, OPTARG shall be unset." |
| */ |
| cp = optarg; |
| if (c == '?') { |
| /* If ":optstring" and unknown option is seen, |
| * it is stored to OPTARG. |
| */ |
| if (optstring[1] == ':') { |
| cbuf[0] = optopt; |
| cp = cbuf; |
| } |
| } |
| if (cp) |
| set_local_var_from_halves("OPTARG", cp); |
| else |
| unset_local_var("OPTARG"); |
| |
| /* Convert -1 to "?" */ |
| exitcode = EXIT_SUCCESS; |
| if (c < 0) { /* -1: end of options */ |
| exitcode = EXIT_FAILURE; |
| c = '?'; |
| } |
| |
| /* Set VAR */ |
| cbuf[0] = c; |
| set_local_var_from_halves(var, cbuf); |
| |
| return exitcode; |
| } |
| #endif |
| |
| static int FAST_FUNC builtin_source(char **argv) |
| { |
| char *arg_path, *filename; |
| HFILE *input; |
| save_arg_t sv; |
| char *args_need_save; |
| #if ENABLE_HUSH_FUNCTIONS |
| smallint sv_flg; |
| #endif |
| |
| argv = skip_dash_dash(argv); |
| filename = argv[0]; |
| if (!filename) { |
| /* bash says: "bash: .: filename argument required" */ |
| return 2; /* bash compat */ |
| } |
| arg_path = NULL; |
| if (!strchr(filename, '/')) { |
| arg_path = find_in_path(filename); |
| if (arg_path) |
| filename = arg_path; |
| else if (!ENABLE_HUSH_BASH_SOURCE_CURDIR) { |
| errno = ENOENT; |
| bb_simple_perror_msg(filename); |
| return EXIT_FAILURE; |
| } |
| } |
| input = hfopen(filename); |
| free(arg_path); |
| if (!input) { |
| bb_perror_msg("%s", filename); |
| /* POSIX: non-interactive shell should abort here, |
| * not merely fail. So far no one complained :) |
| */ |
| return EXIT_FAILURE; |
| } |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| sv_flg = G_flag_return_in_progress; |
| /* "we are inside sourced file, ok to use return" */ |
| G_flag_return_in_progress = -1; |
| #endif |
| args_need_save = argv[1]; /* used as a boolean variable */ |
| if (args_need_save) |
| save_and_replace_G_args(&sv, argv); |
| |
| /* "false; . ./empty_line; echo Zero:$?" should print 0 */ |
| G.last_exitcode = 0; |
| parse_and_run_file(input); |
| hfclose(input); |
| |
| if (args_need_save) /* can't use argv[1] instead: "shift" can mangle it */ |
| restore_G_args(&sv, argv); |
| #if ENABLE_HUSH_FUNCTIONS |
| G_flag_return_in_progress = sv_flg; |
| #endif |
| |
| return G.last_exitcode; |
| } |
| |
| #if ENABLE_HUSH_TRAP |
| static int FAST_FUNC builtin_trap(char **argv) |
| { |
| int sig; |
| char *new_cmd; |
| |
| if (!G_traps) |
| G_traps = xzalloc(sizeof(G_traps[0]) * NSIG); |
| |
| argv++; |
| if (!*argv) { |
| int i; |
| /* No args: print all trapped */ |
| for (i = 0; i < NSIG; ++i) { |
| if (G_traps[i]) { |
| printf("trap -- "); |
| print_escaped(G_traps[i]); |
| /* note: bash adds "SIG", but only if invoked |
| * as "bash". If called as "sh", or if set -o posix, |
| * then it prints short signal names. |
| * We are printing short names: */ |
| printf(" %s\n", get_signame(i)); |
| } |
| } |
| /*fflush_all(); - done after each builtin anyway */ |
| return EXIT_SUCCESS; |
| } |
| |
| new_cmd = NULL; |
| /* If first arg is a number: reset all specified signals */ |
| sig = bb_strtou(*argv, NULL, 10); |
| if (errno == 0) { |
| int ret; |
| process_sig_list: |
| ret = EXIT_SUCCESS; |
| while (*argv) { |
| sighandler_t handler; |
| |
| sig = get_signum(*argv++); |
| if (sig < 0) { |
| ret = EXIT_FAILURE; |
| /* Mimic bash message exactly */ |
| bb_error_msg("trap: %s: invalid signal specification", argv[-1]); |
| continue; |
| } |
| |
| free(G_traps[sig]); |
| G_traps[sig] = xstrdup(new_cmd); |
| |
| debug_printf("trap: setting SIG%s (%i) to '%s'\n", |
| get_signame(sig), sig, G_traps[sig]); |
| |
| /* There is no signal for 0 (EXIT) */ |
| if (sig == 0) |
| continue; |
| |
| if (new_cmd) |
| handler = (new_cmd[0] ? record_pending_signo : SIG_IGN); |
| else |
| /* We are removing trap handler */ |
| handler = pick_sighandler(sig); |
| install_sighandler(sig, handler); |
| } |
| return ret; |
| } |
| |
| if (!argv[1]) { /* no second arg */ |
| bb_simple_error_msg("trap: invalid arguments"); |
| return EXIT_FAILURE; |
| } |
| |
| /* First arg is "-": reset all specified to default */ |
| /* First arg is "--": skip it, the rest is "handler SIGs..." */ |
| /* Everything else: set arg as signal handler |
| * (includes "" case, which ignores signal) */ |
| if (argv[0][0] == '-') { |
| if (argv[0][1] == '\0') { /* "-" */ |
| /* new_cmd remains NULL: "reset these sigs" */ |
| goto reset_traps; |
| } |
| if (argv[0][1] == '-' && argv[0][2] == '\0') { /* "--" */ |
| argv++; |
| } |
| /* else: "-something", no special meaning */ |
| } |
| new_cmd = *argv; |
| reset_traps: |
| argv++; |
| goto process_sig_list; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_JOB |
| static struct pipe *parse_jobspec(const char *str) |
| { |
| struct pipe *pi; |
| unsigned jobnum; |
| |
| if (sscanf(str, "%%%u", &jobnum) != 1) { |
| if (str[0] != '%' |
| || (str[1] != '%' && str[1] != '+' && str[1] != '\0') |
| ) { |
| bb_error_msg("bad argument '%s'", str); |
| return NULL; |
| } |
| /* It is "%%", "%+" or "%" - current job */ |
| jobnum = G.last_jobid; |
| if (jobnum == 0) { |
| bb_simple_error_msg("no current job"); |
| return NULL; |
| } |
| } |
| for (pi = G.job_list; pi; pi = pi->next) { |
| if (pi->jobid == jobnum) { |
| return pi; |
| } |
| } |
| bb_error_msg("%u: no such job", jobnum); |
| return NULL; |
| } |
| |
| static int FAST_FUNC builtin_jobs(char **argv UNUSED_PARAM) |
| { |
| struct pipe *job; |
| const char *status_string; |
| |
| checkjobs(NULL, 0 /*(no pid to wait for)*/); |
| for (job = G.job_list; job; job = job->next) { |
| if (job->alive_cmds == job->stopped_cmds) |
| status_string = "Stopped"; |
| else |
| status_string = "Running"; |
| |
| printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext); |
| } |
| |
| clean_up_last_dead_job(); |
| |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'fg' and 'bg' handler */ |
| static int FAST_FUNC builtin_fg_bg(char **argv) |
| { |
| int i; |
| struct pipe *pi; |
| |
| if (!G_interactive_fd) |
| return EXIT_FAILURE; |
| |
| /* If they gave us no args, assume they want the last backgrounded task */ |
| if (!argv[1]) { |
| for (pi = G.job_list; pi; pi = pi->next) { |
| if (pi->jobid == G.last_jobid) { |
| goto found; |
| } |
| } |
| bb_error_msg("%s: no current job", argv[0]); |
| return EXIT_FAILURE; |
| } |
| |
| pi = parse_jobspec(argv[1]); |
| if (!pi) |
| return EXIT_FAILURE; |
| found: |
| /* TODO: bash prints a string representation |
| * of job being foregrounded (like "sleep 1 | cat") */ |
| if (argv[0][0] == 'f' && G_saved_tty_pgrp) { |
| /* Put the job into the foreground. */ |
| tcsetpgrp(G_interactive_fd, pi->pgrp); |
| } |
| |
| /* Restart the processes in the job */ |
| debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_cmds, pi->pgrp); |
| for (i = 0; i < pi->num_cmds; i++) { |
| debug_printf_jobs("reviving pid %d\n", pi->cmds[i].pid); |
| } |
| pi->stopped_cmds = 0; |
| |
| i = kill(- pi->pgrp, SIGCONT); |
| if (i < 0) { |
| if (errno == ESRCH) { |
| delete_finished_job(pi); |
| return EXIT_SUCCESS; |
| } |
| bb_simple_perror_msg("kill (SIGCONT)"); |
| } |
| |
| if (argv[0][0] == 'f') { |
| remove_job_from_table(pi); /* FG job shouldn't be in job table */ |
| return checkjobs_and_fg_shell(pi); |
| } |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_KILL |
| static int FAST_FUNC builtin_kill(char **argv) |
| { |
| int ret = 0; |
| |
| # if ENABLE_HUSH_JOB |
| if (argv[1] && strcmp(argv[1], "-l") != 0) { |
| int i = 1; |
| |
| do { |
| struct pipe *pi; |
| char *dst; |
| int j, n; |
| |
| if (argv[i][0] != '%') |
| continue; |
| /* |
| * "kill %N" - job kill |
| * Converting to pgrp / pid kill |
| */ |
| pi = parse_jobspec(argv[i]); |
| if (!pi) { |
| /* Eat bad jobspec */ |
| j = i; |
| do { |
| j++; |
| argv[j - 1] = argv[j]; |
| } while (argv[j]); |
| ret = 1; |
| i--; |
| continue; |
| } |
| /* |
| * In jobs started under job control, we signal |
| * entire process group by kill -PGRP_ID. |
| * This happens, f.e., in interactive shell. |
| * |
| * Otherwise, we signal each child via |
| * kill PID1 PID2 PID3. |
| * Testcases: |
| * sh -c 'sleep 1|sleep 1 & kill %1' |
| * sh -c 'true|sleep 2 & sleep 1; kill %1' |
| * sh -c 'true|sleep 1 & sleep 2; kill %1' |
| */ |
| n = G_interactive_fd ? 1 : pi->num_cmds; |
| dst = alloca(n * sizeof(int)*4); |
| argv[i] = dst; |
| if (G_interactive_fd) |
| dst += sprintf(dst, " -%u", (int)pi->pgrp); |
| else for (j = 0; j < n; j++) { |
| struct command *cmd = &pi->cmds[j]; |
| /* Skip exited members of the job */ |
| if (cmd->pid == 0) |
| continue; |
| /* |
| * kill_main has matching code to expect |
| * leading space. Needed to not confuse |
| * negative pids with "kill -SIGNAL_NO" syntax |
| */ |
| dst += sprintf(dst, " %u", (int)cmd->pid); |
| } |
| *dst = '\0'; |
| } while (argv[++i]); |
| } |
| # endif |
| |
| if (argv[1] || ret == 0) { |
| ret = run_applet_main(argv, kill_main); |
| } |
| /* else: ret = 1, "kill %bad_jobspec" case */ |
| return ret; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_WAIT |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */ |
| # if !ENABLE_HUSH_JOB |
| # define wait_for_child_or_signal(pipe,pid) wait_for_child_or_signal(pid) |
| # endif |
| static int wait_for_child_or_signal(struct pipe *waitfor_pipe, pid_t waitfor_pid) |
| { |
| int ret = 0; |
| for (;;) { |
| int sig; |
| sigset_t oldset; |
| |
| if (!sigisemptyset(&G.pending_set)) |
| goto check_sig; |
| |
| /* waitpid is not interruptible by SA_RESTARTed |
| * signals which we use. Thus, this ugly dance: |
| */ |
| |
| /* Make sure possible SIGCHLD is stored in kernel's |
| * pending signal mask before we call waitpid. |
| * Or else we may race with SIGCHLD, lose it, |
| * and get stuck in sigsuspend... |
| */ |
| sigfillset(&oldset); /* block all signals, remember old set */ |
| sigprocmask2(SIG_SETMASK, &oldset); |
| |
| if (!sigisemptyset(&G.pending_set)) { |
| /* Crap! we raced with some signal! */ |
| goto restore; |
| } |
| |
| /*errno = 0; - checkjobs does this */ |
| /* Can't pass waitfor_pipe into checkjobs(): it won't be interruptible */ |
| ret = checkjobs(NULL, waitfor_pid); /* waitpid(WNOHANG) inside */ |
| debug_printf_exec("checkjobs:%d\n", ret); |
| # if ENABLE_HUSH_JOB |
| if (waitfor_pipe) { |
| int rcode = job_exited_or_stopped(waitfor_pipe); |
| debug_printf_exec("job_exited_or_stopped:%d\n", rcode); |
| if (rcode >= 0) { |
| ret = rcode; |
| sigprocmask(SIG_SETMASK, &oldset, NULL); |
| break; |
| } |
| } |
| # endif |
| /* if ECHILD, there are no children (ret is -1 or 0) */ |
| /* if ret == 0, no children changed state */ |
| /* if ret != 0, it's exitcode+1 of exited waitfor_pid child */ |
| if (errno == ECHILD || ret) { |
| ret--; |
| if (ret < 0) /* if ECHILD, may need to fix "ret" */ |
| ret = 0; |
| # if ENABLE_HUSH_BASH_COMPAT |
| if (waitfor_pid == -1 && errno == ECHILD) { |
| /* exitcode of "wait -n" with no children is 127, not 0 */ |
| ret = 127; |
| } |
| # endif |
| sigprocmask(SIG_SETMASK, &oldset, NULL); |
| break; |
| } |
| /* Wait for SIGCHLD or any other signal */ |
| /* It is vitally important for sigsuspend that SIGCHLD has non-DFL handler! */ |
| /* Note: sigsuspend invokes signal handler */ |
| sigsuspend(&oldset); |
| /* ^^^ add "sigdelset(&oldset, SIGCHLD)" before sigsuspend |
| * to make sure SIGCHLD is not masked off? |
| * It was reported that this: |
| * fn() { : | return; } |
| * shopt -s lastpipe |
| * fn |
| * exec hush SCRIPT |
| * under bash 4.4.23 runs SCRIPT with SIGCHLD masked, |
| * making "wait" commands in SCRIPT block forever. |
| */ |
| restore: |
| sigprocmask(SIG_SETMASK, &oldset, NULL); |
| check_sig: |
| /* So, did we get a signal? */ |
| sig = check_and_run_traps(); |
| if (sig /*&& sig != SIGCHLD - always true */) { |
| /* Do this for any (non-ignored) signal, not only for ^C */ |
| ret = 128 | sig; |
| break; |
| } |
| /* SIGCHLD, or no signal, or ignored one, such as SIGQUIT. Repeat */ |
| } |
| return ret; |
| } |
| |
| static int FAST_FUNC builtin_wait(char **argv) |
| { |
| int ret; |
| int status; |
| |
| argv = skip_dash_dash(argv); |
| # if ENABLE_HUSH_BASH_COMPAT |
| if (argv[0] && strcmp(argv[0], "-n") == 0) { |
| /* wait -n */ |
| /* (bash accepts "wait -n PID" too and ignores PID) */ |
| G.dead_job_exitcode = -1; |
| return wait_for_child_or_signal(NULL, -1 /*no job, wait for one job*/); |
| } |
| # endif |
| if (argv[0] == NULL) { |
| /* Don't care about wait results */ |
| /* Note 1: must wait until there are no more children */ |
| /* Note 2: must be interruptible */ |
| /* Examples: |
| * $ sleep 3 & sleep 6 & wait |
| * [1] 30934 sleep 3 |
| * [2] 30935 sleep 6 |
| * [1] Done sleep 3 |
| * [2] Done sleep 6 |
| * $ sleep 3 & sleep 6 & wait |
| * [1] 30936 sleep 3 |
| * [2] 30937 sleep 6 |
| * [1] Done sleep 3 |
| * ^C <-- after ~4 sec from keyboard |
| * $ |
| */ |
| return wait_for_child_or_signal(NULL, 0 /*no job and no pid to wait for*/); |
| } |
| |
| do { |
| pid_t pid = bb_strtou(*argv, NULL, 10); |
| if (errno || pid <= 0) { |
| # if ENABLE_HUSH_JOB |
| if (argv[0][0] == '%') { |
| struct pipe *wait_pipe; |
| ret = 127; /* bash compat for bad jobspecs */ |
| wait_pipe = parse_jobspec(*argv); |
| if (wait_pipe) { |
| ret = job_exited_or_stopped(wait_pipe); |
| if (ret < 0) { |
| ret = wait_for_child_or_signal(wait_pipe, 0); |
| } else { |
| /* waiting on "last dead job" removes it */ |
| clean_up_last_dead_job(); |
| } |
| } |
| /* else: parse_jobspec() already emitted error msg */ |
| continue; |
| } |
| # endif |
| /* mimic bash message */ |
| bb_error_msg("wait: '%s': not a pid or valid job spec", *argv); |
| ret = EXIT_FAILURE; |
| continue; /* bash checks all argv[] */ |
| } |
| |
| /* Do we have such child? */ |
| ret = waitpid(pid, &status, WNOHANG); |
| if (ret < 0) { |
| /* No */ |
| ret = 127; |
| if (errno == ECHILD) { |
| if (pid == G.last_bg_pid) { |
| /* "wait $!" but last bg task has already exited. Try: |
| * (sleep 1; exit 3) & sleep 2; echo $?; wait $!; echo $? |
| * In bash it prints exitcode 0, then 3. |
| * In dash, it is 127. |
| */ |
| ret = G.last_bg_pid_exitcode; |
| } else { |
| /* Example: "wait 1". mimic bash message */ |
| bb_error_msg("wait: pid %u is not a child of this shell", (unsigned)pid); |
| } |
| } else { |
| /* ??? */ |
| bb_perror_msg("wait %s", *argv); |
| } |
| continue; /* bash checks all argv[] */ |
| } |
| if (ret == 0) { |
| /* Yes, and it still runs */ |
| ret = wait_for_child_or_signal(NULL, pid); |
| } else { |
| /* Yes, and it just exited */ |
| process_wait_result(NULL, pid, status); |
| ret = WEXITSTATUS(status); |
| if (WIFSIGNALED(status)) |
| ret = 128 | WTERMSIG(status); |
| } |
| } while (*++argv); |
| |
| return ret; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_LOOPS || ENABLE_HUSH_FUNCTIONS |
| static unsigned parse_numeric_argv1(char **argv, unsigned def, unsigned def_min) |
| { |
| if (argv[1]) { |
| def = bb_strtou(argv[1], NULL, 10); |
| if (errno || def < def_min || argv[2]) { |
| bb_error_msg("%s: bad arguments", argv[0]); |
| def = UINT_MAX; |
| } |
| } |
| return def; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_LOOPS |
| static int FAST_FUNC builtin_break(char **argv) |
| { |
| unsigned depth; |
| if (G.depth_of_loop == 0) { |
| bb_error_msg("%s: only meaningful in a loop", argv[0]); |
| /* if we came from builtin_continue(), need to undo "= 1" */ |
| G.flag_break_continue = 0; |
| return EXIT_SUCCESS; /* bash compat */ |
| } |
| G.flag_break_continue++; /* BC_BREAK = 1, or BC_CONTINUE = 2 */ |
| |
| G.depth_break_continue = depth = parse_numeric_argv1(argv, 1, 1); |
| if (depth == UINT_MAX) |
| G.flag_break_continue = BC_BREAK; |
| if (G.depth_of_loop < depth) |
| G.depth_break_continue = G.depth_of_loop; |
| |
| return EXIT_SUCCESS; |
| } |
| |
| static int FAST_FUNC builtin_continue(char **argv) |
| { |
| G.flag_break_continue = 1; /* BC_CONTINUE = 2 = 1+1 */ |
| return builtin_break(argv); |
| } |
| #endif |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| static int FAST_FUNC builtin_return(char **argv) |
| { |
| int rc; |
| |
| if (G_flag_return_in_progress != -1) { |
| bb_error_msg("%s: not in a function or sourced script", argv[0]); |
| return EXIT_FAILURE; /* bash compat */ |
| } |
| |
| G_flag_return_in_progress = 1; |
| |
| /* bash: |
| * out of range: wraps around at 256, does not error out |
| * non-numeric param: |
| * f() { false; return qwe; }; f; echo $? |
| * bash: return: qwe: numeric argument required <== we do this |
| * 255 <== we also do this |
| */ |
| rc = parse_numeric_argv1(argv, G.last_exitcode, 0); |
| # if ENABLE_HUSH_TRAP |
| if (argv[1]) { /* "return ARG" inside a running trap sets $? */ |
| debug_printf_exec("G.return_exitcode=%d\n", rc); |
| G.return_exitcode = rc; |
| } |
| # endif |
| return rc; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_TIMES |
| static int FAST_FUNC builtin_times(char **argv UNUSED_PARAM) |
| { |
| static const uint8_t times_tbl[] ALIGN1 = { |
| ' ', offsetof(struct tms, tms_utime), |
| '\n', offsetof(struct tms, tms_stime), |
| ' ', offsetof(struct tms, tms_cutime), |
| '\n', offsetof(struct tms, tms_cstime), |
| 0 |
| }; |
| const uint8_t *p; |
| unsigned clk_tck; |
| struct tms buf; |
| |
| clk_tck = bb_clk_tck(); |
| |
| times(&buf); |
| p = times_tbl; |
| do { |
| unsigned sec, frac; |
| unsigned long t; |
| t = *(clock_t *)(((char *) &buf) + p[1]); |
| sec = t / clk_tck; |
| frac = t % clk_tck; |
| printf("%um%u.%03us%c", |
| sec / 60, sec % 60, |
| (frac * 1000) / clk_tck, |
| p[0]); |
| p += 2; |
| } while (*p); |
| |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_MEMLEAK |
| static int FAST_FUNC builtin_memleak(char **argv UNUSED_PARAM) |
| { |
| void *p; |
| unsigned long l; |
| |
| # ifdef M_TRIM_THRESHOLD |
| /* Optional. Reduces probability of false positives */ |
| malloc_trim(0); |
| # endif |
| /* Crude attempt to find where "free memory" starts, |
| * sans fragmentation. */ |
| p = malloc(240); |
| l = (unsigned long)p; |
| free(p); |
| p = malloc(3400); |
| if (l < (unsigned long)p) l = (unsigned long)p; |
| free(p); |
| |
| |
| # if 0 /* debug */ |
| { |
| struct mallinfo mi = mallinfo(); |
| printf("top alloc:0x%lx malloced:%d+%d=%d\n", l, |
| mi.arena, mi.hblkhd, mi.arena + mi.hblkhd); |
| } |
| # endif |
| |
| if (!G.memleak_value) |
| G.memleak_value = l; |
| |
| l -= G.memleak_value; |
| if ((long)l < 0) |
| l = 0; |
| l /= 1024; |
| if (l > 127) |
| l = 127; |
| |
| /* Exitcode is "how many kilobytes we leaked since 1st call" */ |
| return l; |
| } |
| #endif |