| /* 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> |
| * |
| * 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. |
| * |
| * POSIX syntax not implemented: |
| * aliases |
| * <(list) and >(list) Process Substitution |
| * Tilde Expansion |
| * |
| * Bash stuff (optionally enabled): |
| * &> and >& redirection of stdout+stderr |
| * Brace Expansion |
| * reserved words: [[ ]] function select |
| * substrings ${var:1:5} |
| * 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 "expression". |
| * |
| * TODOs: |
| * grep for "TODO" and fix (some of them are easy) |
| * builtins: ulimit |
| * special variables (done: PWD) |
| * follow IFS rules more precisely, including update semantics |
| * export builtin should be special, its arguments are assignments |
| * and therefore expansion of them should be "one-word" expansion: |
| * $ export i=`echo 'a b'` # export has one arg: "i=a b" |
| * compare with: |
| * $ ls i=`echo 'a b'` # ls has 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 |
| * Note1: same applies to local builtin. |
| * Note2: 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 |
| * |
| * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. |
| */ |
| #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */ |
| #include <malloc.h> /* for malloc_trim */ |
| #include <glob.h> |
| /* #include <dmalloc.h> */ |
| #if ENABLE_HUSH_CASE |
| # include <fnmatch.h> |
| #endif |
| #include "math.h" |
| #include "match.h" |
| #if ENABLE_HUSH_RANDOM_SUPPORT |
| # include "random.h" |
| #else |
| # define CLEAR_RANDOM_T(rnd) ((void)0) |
| #endif |
| #ifndef PIPE_BUF |
| # define PIPE_BUF 4096 /* amount of buffering in a pipe */ |
| #endif |
| |
| |
| /* 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 |
| |
| |
| #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 |
| |
| #if defined SINGLE_APPLET_MAIN |
| /* STANDALONE does not make sense, and won't compile */ |
| # undef CONFIG_FEATURE_SH_STANDALONE |
| # undef ENABLE_FEATURE_SH_STANDALONE |
| # undef IF_FEATURE_SH_STANDALONE |
| # define IF_FEATURE_SH_STANDALONE(...) |
| # define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__ |
| # define ENABLE_FEATURE_SH_STANDALONE 0 |
| #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 |
| #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_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_glob(...) do {} while (0) |
| #define debug_printf_list(...) do {} while (0) |
| #define debug_printf_subst(...) do {} while (0) |
| #define debug_printf_clean(...) do {} while (0) |
| |
| #define ERR_PTR ((void*)(long)1) |
| |
| #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" |
| |
| #define SPECIAL_VAR_SYMBOL 3 |
| |
| 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 { |
| char **new_env; |
| struct variable *old_vars; |
| char **argv; |
| char **argv_from_re_execing; |
| } nommu_save_t; |
| #endif |
| |
| typedef enum reserved_style { |
| 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 |
| } reserved_style; |
| |
| typedef struct o_string { |
| char *data; |
| int length; /* position where data is appended */ |
| int maxlen; |
| /* Protect newly added chars against globbing |
| * (by prepending \ to *, ?, [, \) */ |
| smallint o_escape; |
| smallint o_glob; |
| /* At least some part of the string was inside '' or "", |
| * possibly empty one: word"", wo''rd etc. */ |
| smallint o_quoted; |
| smallint has_empty_slot; |
| smallint o_assignment; /* 0:maybe, 1:yes, 2:no */ |
| } o_string; |
| enum { |
| MAYBE_ASSIGNMENT = 0, |
| DEFINITELY_ASSIGNMENT = 1, |
| NOT_ASSIGNMENT = 2, |
| WORD_IS_KEYWORD = 3, /* not assigment, but next word may be: "if v=xyz cmd;" */ |
| }; |
| /* Used for initialization: o_string foo = NULL_O_STRING; */ |
| #define NULL_O_STRING { NULL } |
| |
| /* I can almost use ordinary FILE*. Is open_memstream() universally |
| * available? Where is it documented? */ |
| typedef struct in_str { |
| const char *p; |
| /* eof_flag=1: last char in ->p is really an EOF */ |
| char eof_flag; /* meaningless if ->p == NULL */ |
| char peek_buf[2]; |
| #if ENABLE_HUSH_INTERACTIVE |
| smallint promptme; |
| smallint promptmode; /* 0: PS1, 1: PS2 */ |
| #endif |
| FILE *file; |
| int (*get) (struct in_str *) FAST_FUNC; |
| int (*peek) (struct in_str *) FAST_FUNC; |
| } in_str; |
| #define i_getch(input) ((input)->get(input)) |
| #define i_peek(input) ((input)->peek(input)) |
| |
| /* The descrip member of this structure is only used to make |
| * debugging output pretty */ |
| static const struct { |
| int mode; |
| signed char default_fd; |
| char descrip[3]; |
| } redir_table[] = { |
| { 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 */ |
| int assignment_cnt; /* how many argv[i] are assignments? */ |
| smallint is_stopped; /* is the command currently running? */ |
| smallint cmd_type; /* CMD_xxx */ |
| #define CMD_NORMAL 0 |
| #define CMD_SUBSHELL 1 |
| |
| /* used for "[[ EXPR ]]" */ |
| #if ENABLE_HUSH_BASH_COMPAT |
| # define CMD_SINGLEWORD_NOGLOB 2 |
| #endif |
| |
| /* used for "export noglob=* glob* a=`echo a b`" */ |
| //#define CMD_SINGLEWORD_NOGLOB_COND 3 |
| // It is hard to implement correctly, it adds significant amounts of tricky code, |
| // and all this is only useful for really obscure export statements |
| // almost nobody would use anyway. #ifdef CMD_SINGLEWORD_NOGLOB_COND |
| // guards the code which implements it, but I have doubts it works |
| // in all cases (especially with mixed globbed/non-globbed arguments) |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| # define CMD_FUNCDEF 3 |
| #endif |
| |
| /* 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 |
| int 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 = 1, |
| PIPE_AND = 2, |
| PIPE_OR = 3, |
| PIPE_BG = 4, |
| } 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; |
| #if !BB_MMU |
| o_string as_string; |
| #endif |
| #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 |
| }; |
| |
| /* 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 */ |
| #if ENABLE_HUSH_LOCAL |
| unsigned func_nest_level; |
| #endif |
| int max_len; /* if > 0, name is part of initial env; else name is malloced */ |
| 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 |
| |
| |
| /* "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; |
| const char *PS1; |
| const char *PS2; |
| # 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; |
| int 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 |
| 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; |
| #endif |
| smallint fake_mode; |
| smallint exiting; /* used to prevent EXIT trap recursion */ |
| /* These four support $?, $#, and $1 */ |
| smalluint last_exitcode; |
| /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */ |
| smalluint global_args_malloced; |
| smalluint inherited_set_is_saved; |
| /* 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 |
| const char *ifs; |
| const char *cwd; |
| struct variable *top_var; /* = &G.shell_ver (set in main()) */ |
| struct variable shell_ver; |
| #if ENABLE_HUSH_FUNCTIONS |
| struct function *top_func; |
| # if ENABLE_HUSH_LOCAL |
| struct variable **shadowed_vars_pp; |
| unsigned func_nest_level; |
| # endif |
| #endif |
| /* Signal and trap handling */ |
| #if ENABLE_HUSH_FAST |
| unsigned count_SIGCHLD; |
| unsigned handled_SIGCHLD; |
| smallint we_have_children; |
| #endif |
| /* which signals have non-DFL handler (even with no traps set)? */ |
| unsigned non_DFL_mask; |
| char **traps; /* char *traps[NSIG] */ |
| sigset_t blocked_set; |
| sigset_t inherited_set; |
| #if HUSH_DEBUG |
| unsigned long memleak_value; |
| int debug_indent; |
| #endif |
| char user_input_buf[ENABLE_FEATURE_EDITING ? CONFIG_FEATURE_EDITING_MAX_LEN : 2]; |
| }; |
| #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))); \ |
| } while (0) |
| |
| |
| /* Function prototypes for builtins */ |
| static int builtin_cd(char **argv) FAST_FUNC; |
| static int builtin_echo(char **argv) FAST_FUNC; |
| static int builtin_eval(char **argv) FAST_FUNC; |
| static int builtin_exec(char **argv) FAST_FUNC; |
| static int builtin_exit(char **argv) FAST_FUNC; |
| static int builtin_export(char **argv) FAST_FUNC; |
| #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_HELP |
| static int builtin_help(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_HUSH_LOCAL |
| static int builtin_local(char **argv) FAST_FUNC; |
| #endif |
| #if HUSH_DEBUG |
| static int builtin_memleak(char **argv) FAST_FUNC; |
| #endif |
| #if ENABLE_PRINTF |
| static int builtin_printf(char **argv) FAST_FUNC; |
| #endif |
| static int builtin_pwd(char **argv) FAST_FUNC; |
| static int builtin_read(char **argv) FAST_FUNC; |
| static int builtin_set(char **argv) FAST_FUNC; |
| static int builtin_shift(char **argv) FAST_FUNC; |
| static int builtin_source(char **argv) FAST_FUNC; |
| static int builtin_test(char **argv) FAST_FUNC; |
| static int builtin_trap(char **argv) FAST_FUNC; |
| static int builtin_type(char **argv) FAST_FUNC; |
| static int builtin_true(char **argv) FAST_FUNC; |
| static int builtin_umask(char **argv) FAST_FUNC; |
| static int builtin_unset(char **argv) FAST_FUNC; |
| static int builtin_wait(char **argv) FAST_FUNC; |
| #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 *cmd; |
| int (*function)(char **argv) FAST_FUNC; |
| #if ENABLE_HUSH_HELP |
| const char *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[] = { |
| BLTIN("." , builtin_source , "Run commands in a file"), |
| BLTIN(":" , builtin_true , NULL), |
| #if ENABLE_HUSH_JOB |
| BLTIN("bg" , builtin_fg_bg , "Resume a job in the background"), |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| BLTIN("break" , builtin_break , "Exit from a 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 , "Exit"), |
| BLTIN("export" , builtin_export , "Set environment variables"), |
| #if ENABLE_HUSH_JOB |
| BLTIN("fg" , builtin_fg_bg , "Bring job into the foreground"), |
| #endif |
| #if ENABLE_HUSH_HELP |
| BLTIN("help" , builtin_help , NULL), |
| #endif |
| #if ENABLE_HUSH_JOB |
| BLTIN("jobs" , builtin_jobs , "List jobs"), |
| #endif |
| #if ENABLE_HUSH_LOCAL |
| BLTIN("local" , builtin_local , "Set local variables"), |
| #endif |
| #if HUSH_DEBUG |
| BLTIN("memleak" , builtin_memleak , NULL), |
| #endif |
| BLTIN("read" , builtin_read , "Input into variable"), |
| #if ENABLE_HUSH_FUNCTIONS |
| BLTIN("return" , builtin_return , "Return from a function"), |
| #endif |
| BLTIN("set" , builtin_set , "Set/unset positional parameters"), |
| BLTIN("shift" , builtin_shift , "Shift positional parameters"), |
| BLTIN("trap" , builtin_trap , "Trap signals"), |
| BLTIN("type" , builtin_type , "Write a description of command type"), |
| // BLTIN("ulimit" , builtin_ulimit , "Control resource limits"), |
| BLTIN("umask" , builtin_umask , "Set file creation mask"), |
| BLTIN("unset" , builtin_unset , "Unset variables"), |
| BLTIN("wait" , builtin_wait , "Wait for process"), |
| }; |
| /* For now, echo and test are unconditionally enabled. |
| * Maybe make it configurable? */ |
| static const struct built_in_command bltins2[] = { |
| BLTIN("[" , builtin_test , NULL), |
| BLTIN("echo" , builtin_echo , NULL), |
| #if ENABLE_PRINTF |
| BLTIN("printf" , builtin_printf , NULL), |
| #endif |
| BLTIN("pwd" , builtin_pwd , NULL), |
| BLTIN("test" , builtin_test , NULL), |
| }; |
| |
| |
| /* Debug printouts. |
| */ |
| #if HUSH_DEBUG |
| /* prevent disasters with G.debug_indent < 0 */ |
| # define indent() fprintf(stderr, "%*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(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_parse |
| # define debug_printf_parse(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_exec |
| #define debug_printf_exec(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_env |
| # define debug_printf_env(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_jobs |
| # define debug_printf_jobs(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| # define DEBUG_JOBS 1 |
| #else |
| # define DEBUG_JOBS 0 |
| #endif |
| |
| #ifndef debug_printf_expand |
| # define debug_printf_expand(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| # define DEBUG_EXPAND 1 |
| #else |
| # define DEBUG_EXPAND 0 |
| #endif |
| |
| #ifndef debug_printf_glob |
| # define debug_printf_glob(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| # define DEBUG_GLOB 1 |
| #else |
| # define DEBUG_GLOB 0 |
| #endif |
| |
| #ifndef debug_printf_list |
| # define debug_printf_list(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_subst |
| # define debug_printf_subst(...) (indent(), fprintf(stderr, __VA_ARGS__)) |
| #endif |
| |
| #ifndef debug_printf_clean |
| # define debug_printf_clean(...) (indent(), fprintf(stderr, __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(); |
| fprintf(stderr, "%s:\n", prefix); |
| while (*vv) |
| fprintf(stderr, " '%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 die_if_script(lineno, ...) 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(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); |
| if (!G_interactive_fd) |
| xfunc_die(); |
| } |
| |
| static void syntax_error(unsigned lineno, const char *msg) |
| { |
| if (msg) |
| die_if_script(lineno, "syntax error: %s", msg); |
| else |
| die_if_script(lineno, "syntax error", NULL); |
| } |
| |
| static void syntax_error_at(unsigned lineno, const char *msg) |
| { |
| die_if_script(lineno, "syntax error at '%s'", msg); |
| } |
| |
| static void syntax_error_unterm_str(unsigned lineno, const char *s) |
| { |
| die_if_script(lineno, "syntax error: unterminated %s", s); |
| } |
| |
| /* It so happens that all such cases are totally fatal |
| * even if shell is interactive: EOF while looking for closing |
| * delimiter. There is nowhere to read stuff from after that, |
| * it's EOF! The only choice is to terminate. |
| */ |
| static void syntax_error_unterm_ch(unsigned lineno, char ch) NORETURN; |
| static void syntax_error_unterm_ch(unsigned lineno, char ch) |
| { |
| char msg[2] = { ch, '\0' }; |
| syntax_error_unterm_str(lineno, msg); |
| xfunc_die(); |
| } |
| |
| static void syntax_error_unexpected_ch(unsigned lineno, int ch) |
| { |
| char msg[2]; |
| msg[0] = ch; |
| msg[1] = '\0'; |
| die_if_script(lineno, "syntax error: unexpected %s", ch == EOF ? "EOF" : msg); |
| } |
| |
| #if HUSH_DEBUG < 2 |
| # undef 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 die_if_script(...) 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 |
| |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| static void cmdedit_update_prompt(void); |
| #else |
| # define cmdedit_update_prompt() ((void)0) |
| #endif |
| |
| |
| /* Utility functions |
| */ |
| static int is_well_formed_var_name(const char *s, char terminator) |
| { |
| if (!s || !(isalpha(*s) || *s == '_')) |
| return 0; |
| s++; |
| while (isalnum(*s) || *s == '_') |
| s++; |
| return *s == terminator; |
| } |
| |
| /* 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 ((*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); |
| } |
| |
| |
| /* 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; |
| smallint sv_g_malloced; |
| } save_arg_t; |
| |
| static void save_and_replace_G_args(save_arg_t *sv, char **argv) |
| { |
| int n; |
| |
| sv->sv_argv0 = argv[0]; |
| sv->sv_g_argv = G.global_argv; |
| sv->sv_g_argc = G.global_argc; |
| sv->sv_g_malloced = G.global_args_malloced; |
| |
| argv[0] = G.global_argv[0]; /* retain $0 */ |
| G.global_argv = argv; |
| G.global_args_malloced = 0; |
| |
| n = 1; |
| while (*++argv) |
| n++; |
| G.global_argc = n; |
| } |
| |
| static void restore_G_args(save_arg_t *sv, char **argv) |
| { |
| char **pp; |
| |
| if (G.global_args_malloced) { |
| /* someone ran "set -- arg1 arg2 ...", undo */ |
| pp = G.global_argv; |
| while (*++pp) /* note: does not free $0 */ |
| free(*pp); |
| free(G.global_argv); |
| } |
| argv[0] = sv->sv_argv0; |
| G.global_argv = sv->sv_g_argv; |
| G.global_argc = sv->sv_g_argc; |
| 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 in 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 |
| * |
| * (What happens to signals which are IGN on shell start?) |
| * (What happens with signal mask on shell start?) |
| * |
| * Implementation in hush |
| * ====================== |
| * 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 non_DFL_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 non_DFL_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. |
| */ |
| enum { |
| SPECIAL_INTERACTIVE_SIGS = 0 |
| | (1 << SIGTERM) |
| | (1 << SIGINT) |
| | (1 << SIGHUP) |
| , |
| SPECIAL_JOB_SIGS = 0 |
| #if ENABLE_HUSH_JOB |
| | (1 << SIGTTIN) |
| | (1 << SIGTTOU) |
| | (1 << SIGTSTP) |
| #endif |
| }; |
| |
| #if ENABLE_HUSH_FAST |
| static void SIGCHLD_handler(int sig UNUSED_PARAM) |
| { |
| 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 |
| |
| #if ENABLE_HUSH_JOB |
| |
| /* After [v]fork, in child: do not restore tty pgrp on xfunc death */ |
| #define disable_restore_tty_pgrp_on_exit() (die_sleep = 0) |
| /* After [v]fork, in parent: restore tty pgrp on xfunc death */ |
| #define enable_restore_tty_pgrp_on_exit() (die_sleep = -1) |
| |
| /* 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) |
| { |
| /* Disable all signals: job control, SIGPIPE, etc. */ |
| sigprocmask_allsigs(SIG_BLOCK); |
| |
| /* 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); |
| |
| /* 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 |
| |
| /* Restores tty foreground process group, and exits. */ |
| static void hush_exit(int exitcode) NORETURN; |
| static void hush_exit(int exitcode) |
| { |
| if (G.exiting <= 0 && G.traps && G.traps[0] && G.traps[0][0]) { |
| /* Prevent recursion: |
| * trap "echo Hi; exit" EXIT; exit |
| */ |
| char *argv[] = { NULL, G.traps[0], NULL }; |
| G.traps[0] = NULL; |
| G.exiting = 1; |
| builtin_eval(argv); |
| free(argv[1]); |
| } |
| |
| #if ENABLE_HUSH_JOB |
| fflush_all(); |
| sigexit(- (exitcode & 0xff)); |
| #else |
| exit(exitcode); |
| #endif |
| } |
| |
| static int check_and_run_traps(int sig) |
| { |
| static const struct timespec zero_timespec = { 0, 0 }; |
| smalluint save_rcode; |
| int last_sig = 0; |
| |
| if (sig) |
| goto jump_in; |
| while (1) { |
| sig = sigtimedwait(&G.blocked_set, NULL, &zero_timespec); |
| if (sig <= 0) |
| break; |
| jump_in: |
| last_sig = sig; |
| if (G.traps && G.traps[sig]) { |
| if (G.traps[sig][0]) { |
| /* We have user-defined handler */ |
| char *argv[] = { NULL, xstrdup(G.traps[sig]), NULL }; |
| save_rcode = G.last_exitcode; |
| builtin_eval(argv); |
| free(argv[1]); |
| G.last_exitcode = save_rcode; |
| } /* else: "" trap, ignoring signal */ |
| continue; |
| } |
| /* not a trap: special action */ |
| switch (sig) { |
| #if ENABLE_HUSH_FAST |
| case SIGCHLD: |
| 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); |
| break; |
| #endif |
| case SIGINT: |
| /* Builtin was ^C'ed, make it look prettier: */ |
| bb_putchar('\n'); |
| G.flag_SIGINT = 1; |
| break; |
| #if ENABLE_HUSH_JOB |
| case SIGHUP: { |
| struct pipe *job; |
| /* 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 |
| default: /* ignored: */ |
| /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */ |
| 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) |
| { |
| struct variable **pp; |
| struct variable *cur; |
| int len; |
| |
| len = strlen(name); |
| 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 struct variable *get_local_var(const char *name) |
| { |
| struct variable **pp = get_ptr_to_local_var(name); |
| if (pp) |
| return *pp; |
| return NULL; |
| } |
| |
| static const char *get_local_var_value(const char *name) |
| { |
| struct variable **pp = get_ptr_to_local_var(name); |
| if (pp) |
| return strchr((*pp)->varstr, '=') + 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 |
| return NULL; |
| } |
| |
| /* str holds "NAME=VAL" and is expected to be malloced. |
| * We take ownership of it. |
| * flg_export: |
| * 0: do not change export flag |
| * (if creating new variable, flag will be 0) |
| * 1: set export flag and putenv the variable |
| * -1: clear export flag and unsetenv the variable |
| * flg_read_only is set only when we handle -R var=val |
| */ |
| #if !BB_MMU && ENABLE_HUSH_LOCAL |
| /* all params are used */ |
| #elif BB_MMU && ENABLE_HUSH_LOCAL |
| #define set_local_var(str, flg_export, local_lvl, flg_read_only) \ |
| set_local_var(str, flg_export, local_lvl) |
| #elif BB_MMU && !ENABLE_HUSH_LOCAL |
| #define set_local_var(str, flg_export, local_lvl, flg_read_only) \ |
| set_local_var(str, flg_export) |
| #elif !BB_MMU && !ENABLE_HUSH_LOCAL |
| #define set_local_var(str, flg_export, local_lvl, flg_read_only) \ |
| set_local_var(str, flg_export, flg_read_only) |
| #endif |
| static int set_local_var(char *str, int flg_export, int local_lvl, int flg_read_only) |
| { |
| struct variable **var_pp; |
| struct variable *cur; |
| char *eq_sign; |
| int name_len; |
| |
| eq_sign = strchr(str, '='); |
| if (!eq_sign) { /* not expected to ever happen? */ |
| free(str); |
| return -1; |
| } |
| |
| name_len = eq_sign - str + 1; /* including '=' */ |
| var_pp = &G.top_var; |
| while ((cur = *var_pp) != NULL) { |
| if (strncmp(cur->varstr, str, name_len) != 0) { |
| var_pp = &cur->next; |
| continue; |
| } |
| /* We found an existing var with this name */ |
| if (cur->flg_read_only) { |
| #if !BB_MMU |
| if (!flg_read_only) |
| #endif |
| bb_error_msg("%s: readonly variable", str); |
| free(str); |
| return -1; |
| } |
| if (flg_export == -1) { // "&& cur->flg_export" ? |
| debug_printf_env("%s: unsetenv '%s'\n", __func__, str); |
| *eq_sign = '\0'; |
| unsetenv(str); |
| *eq_sign = '='; |
| } |
| #if ENABLE_HUSH_LOCAL |
| if (cur->func_nest_level < local_lvl) { |
| /* New variable is declared as local, |
| * and existing one is global, or local |
| * from enclosing function. |
| * Remove and save old one: */ |
| *var_pp = cur->next; |
| cur->next = *G.shadowed_vars_pp; |
| *G.shadowed_vars_pp = cur; |
| /* 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) |
| flg_export = 1; |
| break; |
| } |
| #endif |
| if (strcmp(cur->varstr + name_len, eq_sign + 1) == 0) { |
| free_and_exp: |
| free(str); |
| goto exp; |
| } |
| if (cur->max_len != 0) { |
| if (cur->max_len >= strlen(str)) { |
| /* This one is from startup env, reuse space */ |
| strcpy(cur->varstr, str); |
| goto free_and_exp; |
| } |
| } else { |
| /* max_len == 0 signifies "malloced" var, which we can |
| * (and has to) free */ |
| free(cur->varstr); |
| } |
| cur->max_len = 0; |
| goto set_str_and_exp; |
| } |
| |
| /* Not found - create new variable struct */ |
| cur = xzalloc(sizeof(*cur)); |
| #if ENABLE_HUSH_LOCAL |
| cur->func_nest_level = local_lvl; |
| #endif |
| cur->next = *var_pp; |
| *var_pp = cur; |
| |
| set_str_and_exp: |
| cur->varstr = str; |
| #if !BB_MMU |
| cur->flg_read_only = flg_read_only; |
| #endif |
| exp: |
| if (flg_export == 1) |
| cur->flg_export = 1; |
| if (name_len == 4 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S') |
| cmdedit_update_prompt(); |
| if (cur->flg_export) { |
| if (flg_export == -1) { |
| cur->flg_export = 0; |
| /* unsetenv was already done */ |
| } else { |
| debug_printf_env("%s: putenv '%s'\n", __func__, cur->varstr); |
| return putenv(cur->varstr); |
| } |
| } |
| return 0; |
| } |
| |
| /* Used at startup and after each cd */ |
| static void set_pwd_var(int exp) |
| { |
| set_local_var(xasprintf("PWD=%s", get_cwd(/*force:*/ 1)), |
| /*exp:*/ exp, /*lvl:*/ 0, /*ro:*/ 0); |
| } |
| |
| static int unset_local_var_len(const char *name, int name_len) |
| { |
| struct variable *cur; |
| struct variable **var_pp; |
| |
| if (!name) |
| return EXIT_SUCCESS; |
| var_pp = &G.top_var; |
| while ((cur = *var_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; |
| } |
| *var_pp = cur->next; |
| debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr); |
| bb_unsetenv(cur->varstr); |
| if (name_len == 3 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S') |
| cmdedit_update_prompt(); |
| if (!cur->max_len) |
| free(cur->varstr); |
| free(cur); |
| return EXIT_SUCCESS; |
| } |
| var_pp = &cur->next; |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| static int unset_local_var(const char *name) |
| { |
| return unset_local_var_len(name, strlen(name)); |
| } |
| |
| static void unset_vars(char **strings) |
| { |
| char **v; |
| |
| if (!strings) |
| return; |
| v = strings; |
| while (*v) { |
| const char *eq = strchrnul(*v, '='); |
| unset_local_var_len(*v, (int)(eq - *v)); |
| v++; |
| } |
| free(strings); |
| } |
| |
| #if ENABLE_SH_MATH_SUPPORT |
| #define is_name(c) ((c) == '_' || isalpha((unsigned char)(c))) |
| #define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c))) |
| static char *endofname(const char *name) |
| { |
| char *p; |
| |
| p = (char *) name; |
| if (!is_name(*p)) |
| return p; |
| while (*++p) { |
| if (!is_in_name(*p)) |
| break; |
| } |
| return p; |
| } |
| |
| static void arith_set_local_var(const char *name, const char *val, int flags) |
| { |
| /* arith code doesnt malloc space, so do it for it */ |
| char *var = xasprintf("%s=%s", name, val); |
| set_local_var(var, flags, /*lvl:*/ 0, /*ro:*/ 0); |
| } |
| #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'\n", __func__, var->varstr); |
| putenv(var->varstr); |
| } else { |
| debug_printf_env("%s: restoring variable '%s'\n", __func__, var->varstr); |
| } |
| var = next; |
| } |
| } |
| |
| static struct variable *set_vars_and_save_old(char **strings) |
| { |
| char **s; |
| struct variable *old = NULL; |
| |
| if (!strings) |
| return old; |
| s = strings; |
| while (*s) { |
| struct variable *var_p; |
| struct variable **var_pp; |
| char *eq; |
| |
| eq = strchr(*s, '='); |
| if (eq) { |
| *eq = '\0'; |
| var_pp = get_ptr_to_local_var(*s); |
| *eq = '='; |
| if (var_pp) { |
| /* Remove variable from global linked list */ |
| var_p = *var_pp; |
| debug_printf_env("%s: removing '%s'\n", __func__, var_p->varstr); |
| *var_pp = var_p->next; |
| /* Add it to returned list */ |
| var_p->next = old; |
| old = var_p; |
| } |
| set_local_var(*s, /*exp:*/ 1, /*lvl:*/ 0, /*ro:*/ 0); |
| } |
| s++; |
| } |
| return old; |
| } |
| |
| |
| /* |
| * in_str support |
| */ |
| static int FAST_FUNC static_get(struct in_str *i) |
| { |
| int ch = *i->p++; |
| if (ch != '\0') |
| return ch; |
| i->p--; |
| return EOF; |
| } |
| |
| static int FAST_FUNC static_peek(struct in_str *i) |
| { |
| return *i->p; |
| } |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| |
| static void cmdedit_update_prompt(void) |
| { |
| if (ENABLE_FEATURE_EDITING_FANCY_PROMPT) { |
| G.PS1 = get_local_var_value("PS1"); |
| if (G.PS1 == NULL) |
| G.PS1 = "\\w \\$ "; |
| G.PS2 = get_local_var_value("PS2"); |
| } else { |
| G.PS1 = NULL; |
| } |
| if (G.PS2 == NULL) |
| G.PS2 = "> "; |
| } |
| |
| static const char* setup_prompt_string(int promptmode) |
| { |
| const char *prompt_str; |
| debug_printf("setup_prompt_string %d ", promptmode); |
| if (!ENABLE_FEATURE_EDITING_FANCY_PROMPT) { |
| /* Set up the prompt */ |
| if (promptmode == 0) { /* PS1 */ |
| free((char*)G.PS1); |
| /* bash uses $PWD value, even if it is set by user. |
| * It uses current dir only if PWD is unset. |
| * We always use current dir. */ |
| G.PS1 = xasprintf("%s %c ", get_cwd(0), (geteuid() != 0) ? '$' : '#'); |
| prompt_str = G.PS1; |
| } else |
| prompt_str = G.PS2; |
| } else |
| prompt_str = (promptmode == 0) ? G.PS1 : G.PS2; |
| debug_printf("result '%s'\n", prompt_str); |
| return prompt_str; |
| } |
| |
| static void get_user_input(struct in_str *i) |
| { |
| int r; |
| const char *prompt_str; |
| |
| prompt_str = setup_prompt_string(i->promptmode); |
| #if ENABLE_FEATURE_EDITING |
| /* Enable command line editing only while a command line |
| * is actually being read */ |
| do { |
| G.flag_SIGINT = 0; |
| /* buglet: SIGINT will not make new prompt to appear _at once_, |
| * only after <Enter>. (^C will work) */ |
| r = read_line_input(prompt_str, G.user_input_buf, CONFIG_FEATURE_EDITING_MAX_LEN-1, G.line_input_state); |
| /* catch *SIGINT* etc (^C is handled by read_line_input) */ |
| check_and_run_traps(0); |
| } while (r == 0 || G.flag_SIGINT); /* repeat if ^C or SIGINT */ |
| i->eof_flag = (r < 0); |
| if (i->eof_flag) { /* EOF/error detected */ |
| G.user_input_buf[0] = EOF; /* yes, it will be truncated, it's ok */ |
| G.user_input_buf[1] = '\0'; |
| } |
| #else |
| do { |
| G.flag_SIGINT = 0; |
| fputs(prompt_str, stdout); |
| fflush_all(); |
| G.user_input_buf[0] = r = fgetc(i->file); |
| /*G.user_input_buf[1] = '\0'; - already is and never changed */ |
| //do we need check_and_run_traps(0)? (maybe only if stdin) |
| } while (G.flag_SIGINT); |
| i->eof_flag = (r == EOF); |
| #endif |
| i->p = G.user_input_buf; |
| } |
| |
| #endif /* INTERACTIVE */ |
| |
| /* This is the magic location that prints prompts |
| * and gets data back from the user */ |
| static int FAST_FUNC file_get(struct in_str *i) |
| { |
| int ch; |
| |
| /* If there is data waiting, eat it up */ |
| if (i->p && *i->p) { |
| #if ENABLE_HUSH_INTERACTIVE |
| take_cached: |
| #endif |
| ch = *i->p++; |
| if (i->eof_flag && !*i->p) |
| ch = EOF; |
| /* note: ch is never NUL */ |
| } else { |
| /* need to double check i->file because we might be doing something |
| * more complicated by now, like sourcing or substituting. */ |
| #if ENABLE_HUSH_INTERACTIVE |
| if (G_interactive_fd && i->promptme && i->file == stdin) { |
| do { |
| get_user_input(i); |
| } while (!*i->p); /* need non-empty line */ |
| i->promptmode = 1; /* PS2 */ |
| i->promptme = 0; |
| goto take_cached; |
| } |
| #endif |
| do ch = fgetc(i->file); while (ch == '\0'); |
| } |
| debug_printf("file_get: got '%c' %d\n", ch, ch); |
| #if ENABLE_HUSH_INTERACTIVE |
| if (ch == '\n') |
| i->promptme = 1; |
| #endif |
| return ch; |
| } |
| |
| /* All callers guarantee this routine will never |
| * be used right after a newline, so prompting is not needed. |
| */ |
| static int FAST_FUNC file_peek(struct in_str *i) |
| { |
| int ch; |
| if (i->p && *i->p) { |
| if (i->eof_flag && !i->p[1]) |
| return EOF; |
| return *i->p; |
| /* note: ch is never NUL */ |
| } |
| do ch = fgetc(i->file); while (ch == '\0'); |
| i->eof_flag = (ch == EOF); |
| i->peek_buf[0] = ch; |
| i->peek_buf[1] = '\0'; |
| i->p = i->peek_buf; |
| debug_printf("file_peek: got '%c' %d\n", ch, ch); |
| return ch; |
| } |
| |
| static void setup_file_in_str(struct in_str *i, FILE *f) |
| { |
| i->peek = file_peek; |
| i->get = file_get; |
| #if ENABLE_HUSH_INTERACTIVE |
| i->promptme = 1; |
| i->promptmode = 0; /* PS1 */ |
| #endif |
| i->file = f; |
| i->p = NULL; |
| } |
| |
| static void setup_string_in_str(struct in_str *i, const char *s) |
| { |
| i->peek = static_peek; |
| i->get = static_get; |
| #if ENABLE_HUSH_INTERACTIVE |
| i->promptme = 1; |
| i->promptmode = 0; /* PS1 */ |
| #endif |
| i->p = s; |
| i->eof_flag = 0; |
| } |
| |
| |
| /* |
| * o_string support |
| */ |
| #define B_CHUNK (32 * sizeof(char*)) |
| |
| static void o_reset_to_empty_unquoted(o_string *o) |
| { |
| o->length = 0; |
| o->o_quoted = 0; |
| if (o->data) |
| o->data[0] = '\0'; |
| } |
| |
| static void o_free(o_string *o) |
| { |
| free(o->data); |
| memset(o, 0, sizeof(*o)); |
| } |
| |
| static ALWAYS_INLINE void o_free_unsafe(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 ? 2*len : B_CHUNK); |
| 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); |
| o_grow_by(o, 1); |
| o->data[o->length] = ch; |
| o->length++; |
| o->data[o->length] = '\0'; |
| } |
| |
| static void o_addblock(o_string *o, const char *str, int len) |
| { |
| o_grow_by(o, len); |
| memcpy(&o->data[o->length], str, len); |
| o->length += len; |
| o->data[o->length] = '\0'; |
| } |
| |
| #if !BB_MMU |
| static void o_addstr(o_string *o, const char *str) |
| { |
| o_addblock(o, str, strlen(str)); |
| } |
| static void nommu_addchr(o_string *o, int ch) |
| { |
| if (o) |
| o_addchr(o, ch); |
| } |
| #else |
| # define nommu_addchr(o, str) ((void)0) |
| #endif |
| |
| static void o_addstr_with_NUL(o_string *o, const char *str) |
| { |
| o_addblock(o, str, strlen(str) + 1); |
| } |
| |
| static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len) |
| { |
| while (len) { |
| o_addchr(o, *str); |
| if (*str++ == '\\' |
| && (*str != '*' && *str != '?' && *str != '[') |
| ) { |
| o_addchr(o, '\\'); |
| } |
| len--; |
| } |
| } |
| |
| #undef HUSH_BRACE_EXP |
| /* |
| * HUSH_BRACE_EXP 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. |
| */ |
| |
| #ifdef HUSH_BRACE_EXP |
| # 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; |
| 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_escape && 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_addQstr(o_string *o, const char *str, int len) |
| { |
| if (!o->o_escape) { |
| o_addblock(o, str, len); |
| return; |
| } |
| 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; |
| 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'; |
| } |
| } |
| |
| /* 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(); |
| fprintf(stderr, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d\n", |
| prefix, list, n, string_start, o->length, o->maxlen); |
| while (i < n) { |
| indent(); |
| fprintf(stderr, " list[%d]=%d '%s' %p\n", i, (int)list[i], |
| o->data + (int)list[i] + string_start, |
| o->data + (int)list[i] + string_start); |
| i++; |
| } |
| if (n) { |
| const char *p = o->data + (int)list[n - 1] + string_start; |
| indent(); |
| fprintf(stderr, " 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); |
| 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; |
| } |
| list[n] = (char*)(ptrdiff_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)(ptrdiff_t)list[n-1]) + string_start; |
| } |
| |
| #ifdef HUSH_BRACE_EXP |
| /* 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_error_msg_and_die(bb_msg_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 o_glob(o_string *o, int n) |
| { |
| char *pattern, *copy; |
| |
| debug_printf_glob("start o_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("o_glob returning", o, n); |
| return n; |
| } |
| |
| #else |
| |
| /* 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 o_glob(o_string *o, int n) |
| { |
| glob_t globdata; |
| int gr; |
| char *pattern; |
| |
| debug_printf_glob("start o_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_error_msg_and_die(bb_msg_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("o_glob returning", o, n); |
| return n; |
| } |
| |
| #endif |
| |
| /* If o->o_glob == 1, 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_glob) { /* if globbing is requested */ |
| /* 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 o_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; |
| |
| n = o_save_ptr(o, n); /* force growth for list[n] if necessary */ |
| 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)(ptrdiff_t)list[n] + string_start; |
| } |
| return list; |
| } |
| |
| |
| /* Expansion can recurse */ |
| #if ENABLE_HUSH_TICK |
| static int process_command_subs(o_string *dest, const char *s); |
| #endif |
| static char *expand_string_to_string(const char *str); |
| #if BB_MMU |
| #define parse_stream_dquoted(as_string, dest, input, dquote_end) \ |
| parse_stream_dquoted(dest, input, dquote_end) |
| #endif |
| static int parse_stream_dquoted(o_string *as_string, |
| o_string *dest, |
| struct in_str *input, |
| int dquote_end); |
| |
| /* 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 $VAR). |
| * This new list is allocated as a single malloc block. |
| * NULL-terminated list of char* pointers is at the beginning of it, |
| * followed by strings themself. |
| * Caller can deallocate entire list by single free(list). */ |
| |
| /* Store given string, finalizing the word and starting new one whenever |
| * we encounter IFS char(s). This is used for expanding variable values. |
| * End-of-string does NOT finalize word: think about 'echo -$VAR-' */ |
| static int expand_on_ifs(o_string *output, int n, const char *str) |
| { |
| while (1) { |
| int word_len = strcspn(str, G.ifs); |
| if (word_len) { |
| if (output->o_escape || !output->o_glob) |
| o_addQstr(output, str, word_len); |
| else /* protect backslashes against globbing up :) */ |
| o_addblock_duplicate_backslash(output, str, word_len); |
| str += word_len; |
| } |
| if (!*str) /* EOL - do not finalize word */ |
| break; |
| o_addchr(output, '\0'); |
| debug_print_list("expand_on_ifs", output, n); |
| n = o_save_ptr(output, n); |
| str += strspn(str, G.ifs); /* skip ifs chars */ |
| } |
| 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 $var and `cmd`" |
| * |
| * Returns malloced string. |
| * As an optimization, we return NULL if expansion is not needed. |
| */ |
| static char *expand_pseudo_dquoted(const char *str) |
| { |
| char *exp_str; |
| struct in_str input; |
| o_string dest = NULL_O_STRING; |
| |
| if (strchr(str, '$') == NULL |
| #if ENABLE_HUSH_TICK |
| && strchr(str, '`') == NULL |
| #endif |
| ) { |
| return NULL; |
| } |
| |
| /* We need to expand. Example: |
| * echo $(($a + `echo 1`)) $((1 + $((2)) )) |
| */ |
| setup_string_in_str(&input, str); |
| parse_stream_dquoted(NULL, &dest, &input, EOF); |
| //bb_error_msg("'%s' -> '%s'", str, dest.data); |
| exp_str = expand_string_to_string(dest.data); |
| //bb_error_msg("'%s' -> '%s'", dest.data, exp_str); |
| o_free_unsafe(&dest); |
| return exp_str; |
| } |
| |
| /* 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, char or_mask) |
| { |
| /* or_mask is either 0 (normal case) or 0x80 - |
| * expansion of right-hand side of assignment == 1-element expand. |
| * It will also do no globbing, and thus we must not backslash-quote! |
| */ |
| char ored_ch; |
| char *p; |
| |
| ored_ch = 0; |
| |
| debug_printf_expand("expand_vars_to_list: arg:'%s' or_mask:%x\n", arg, or_mask); |
| debug_print_list("expand_vars_to_list", output, n); |
| n = o_save_ptr(output, n); |
| debug_print_list("expand_vars_to_list[0]", output, n); |
| |
| while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) { |
| char first_ch; |
| int i; |
| char *dyn_val = NULL; |
| const char *val = NULL; |
| #if ENABLE_HUSH_TICK |
| o_string subst_result = NULL_O_STRING; |
| #endif |
| #if ENABLE_SH_MATH_SUPPORT |
| char arith_buf[sizeof(arith_t)*3 + 2]; |
| #endif |
| o_addblock(output, arg, p - arg); |
| debug_print_list("expand_vars_to_list[1]", output, n); |
| arg = ++p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| |
| first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */ |
| /* "$@" is special. Even if quoted, it can still |
| * expand to nothing (not even an empty string) */ |
| if ((first_ch & 0x7f) != '@') |
| ored_ch |= first_ch; |
| |
| switch (first_ch & 0x7f) { |
| /* Highest bit in first_ch indicates that var is double-quoted */ |
| case '$': /* pid */ |
| val = utoa(G.root_pid); |
| break; |
| case '!': /* bg pid */ |
| val = G.last_bg_pid ? utoa(G.last_bg_pid) : (char*)""; |
| break; |
| case '?': /* exitcode */ |
| val = utoa(G.last_exitcode); |
| break; |
| case '#': /* argc */ |
| if (arg[1] != SPECIAL_VAR_SYMBOL) |
| /* actually, it's a ${#var} */ |
| goto case_default; |
| val = utoa(G.global_argc ? G.global_argc-1 : 0); |
| break; |
| case '*': |
| case '@': |
| i = 1; |
| if (!G.global_argv[i]) |
| break; |
| ored_ch |= first_ch; /* do it for "$@" _now_, when we know it's not empty */ |
| if (!(first_ch & 0x80)) { /* unquoted $* or $@ */ |
| smallint sv = output->o_escape; |
| /* unquoted var's contents should be globbed, so don't escape */ |
| output->o_escape = 0; |
| while (G.global_argv[i]) { |
| n = expand_on_ifs(output, n, G.global_argv[i]); |
| debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1); |
| if (G.global_argv[i++][0] && G.global_argv[i]) { |
| /* this argv[] is not empty and not last: |
| * put terminating NUL, start new word */ |
| o_addchr(output, '\0'); |
| debug_print_list("expand_vars_to_list[2]", output, n); |
| n = o_save_ptr(output, n); |
| debug_print_list("expand_vars_to_list[3]", output, n); |
| } |
| } |
| output->o_escape = sv; |
| } else |
| /* If or_mask is nonzero, we handle assignment 'a=....$@.....' |
| * and in this case should treat it like '$*' - see 'else...' below */ |
| if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */ |
| while (1) { |
| o_addQstr(output, G.global_argv[i], strlen(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 $*: add as one word */ |
| while (1) { |
| o_addQstr(output, G.global_argv[i], strlen(G.global_argv[i])); |
| if (!G.global_argv[++i]) |
| break; |
| if (G.ifs[0]) |
| o_addchr(output, G.ifs[0]); |
| } |
| } |
| break; |
| case SPECIAL_VAR_SYMBOL: /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */ |
| /* "Empty variable", used to make "" etc to not disappear */ |
| arg++; |
| ored_ch = 0x80; |
| break; |
| #if ENABLE_HUSH_TICK |
| case '`': /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */ |
| *p = '\0'; |
| arg++; |
| /* Can't just stuff it into output o_string, |
| * expanded result may need to be globbed |
| * and $IFS-splitted */ |
| debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch); |
| G.last_exitcode = process_command_subs(&subst_result, arg); |
| debug_printf_subst("SUBST RES '%s'\n", subst_result.data); |
| val = subst_result.data; |
| goto store_val; |
| #endif |
| #if ENABLE_SH_MATH_SUPPORT |
| case '+': { /* <SPECIAL_VAR_SYMBOL>+cmd<SPECIAL_VAR_SYMBOL> */ |
| arith_eval_hooks_t hooks; |
| arith_t res; |
| int errcode; |
| char *exp_str; |
| |
| arg++; /* skip '+' */ |
| *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */ |
| debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch); |
| |
| exp_str = expand_pseudo_dquoted(arg); |
| hooks.lookupvar = get_local_var_value; |
| hooks.setvar = arith_set_local_var; |
| hooks.endofname = endofname; |
| res = arith(exp_str ? exp_str : arg, &errcode, &hooks); |
| free(exp_str); |
| |
| if (errcode < 0) { |
| const char *msg = "error in arithmetic"; |
| switch (errcode) { |
| case -3: |
| msg = "exponent less than 0"; |
| break; |
| case -2: |
| msg = "divide by 0"; |
| break; |
| case -5: |
| msg = "expression recursion loop detected"; |
| break; |
| } |
| die_if_script(msg); |
| } |
| debug_printf_subst("ARITH RES '"arith_t_fmt"'\n", res); |
| sprintf(arith_buf, arith_t_fmt, res); |
| val = arith_buf; |
| break; |
| } |
| #endif |
| default: /* <SPECIAL_VAR_SYMBOL>varname<SPECIAL_VAR_SYMBOL> */ |
| case_default: { |
| bool exp_len = false; |
| bool exp_null = false; |
| char *var = arg; |
| char exp_save = exp_save; /* for compiler */ |
| char exp_op = exp_op; /* for compiler */ |
| char *exp_word = exp_word; /* for compiler */ |
| size_t exp_off = 0; |
| |
| *p = '\0'; |
| arg[0] = first_ch & 0x7f; |
| |
| /* prepare for expansions */ |
| if (var[0] == '#') { |
| /* handle length expansion ${#var} */ |
| exp_len = true; |
| ++var; |
| } else { |
| /* maybe handle parameter expansion */ |
| exp_off = strcspn(var, ":-=+?%#"); |
| if (!var[exp_off]) |
| exp_off = 0; |
| if (exp_off) { |
| exp_save = var[exp_off]; |
| exp_null = exp_save == ':'; |
| exp_word = var + exp_off; |
| if (exp_null) |
| ++exp_word; |
| exp_op = *exp_word++; |
| var[exp_off] = '\0'; |
| } |
| } |
| |
| /* lookup the variable in question */ |
| if (isdigit(var[0])) { |
| /* handle_dollar() should have vetted var for us */ |
| i = xatoi_u(var); |
| if (i < G.global_argc) |
| val = G.global_argv[i]; |
| /* else val remains NULL: $N with too big N */ |
| } else |
| val = get_local_var_value(var); |
| |
| /* handle any expansions */ |
| if (exp_len) { |
| debug_printf_expand("expand: length of '%s' = ", val); |
| val = utoa(val ? strlen(val) : 0); |
| debug_printf_expand("%s\n", val); |
| } else if (exp_off) { |
| if (exp_op == '%' || exp_op == '#') { |
| if (val) { |
| /* we need to do a pattern match */ |
| bool match_at_left; |
| char *loc; |
| scan_t scan = pick_scan(exp_op, *exp_word, &match_at_left); |
| if (exp_op == *exp_word) /* ## or %% */ |
| ++exp_word; |
| val = dyn_val = xstrdup(val); |
| loc = scan(dyn_val, exp_word, match_at_left); |
| if (match_at_left) /* # or ## */ |
| val = loc; |
| else if (loc) /* % or %% and match was found */ |
| *loc = '\0'; |
| } |
| } else { |
| /* we need to do an expansion */ |
| int exp_test = (!val || (exp_null && !val[0])); |
| if (exp_op == '+') |
| exp_test = !exp_test; |
| debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op, |
| exp_null ? "true" : "false", exp_test); |
| if (exp_test) { |
| if (exp_op == '?') { |
| //TODO: how interactive bash aborts expansion mid-command? |
| /* ${var?[error_msg_if_unset]} */ |
| /* ${var:?[error_msg_if_unset_or_null]} */ |
| /* mimic bash message */ |
| die_if_script("%s: %s", |
| var, |
| exp_word[0] ? exp_word : "parameter null or not set" |
| ); |
| } else { |
| val = exp_word; |
| } |
| |
| if (exp_op == '=') { |
| /* ${var=[word]} or ${var:=[word]} */ |
| if (isdigit(var[0]) || var[0] == '#') { |
| /* mimic bash message */ |
| die_if_script("$%s: cannot assign in this way", var); |
| val = NULL; |
| } else { |
| char *new_var = xasprintf("%s=%s", var, val); |
| set_local_var(new_var, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0); |
| } |
| } |
| } |
| } |
| |
| var[exp_off] = exp_save; |
| } |
| |
| arg[0] = first_ch; |
| #if ENABLE_HUSH_TICK |
| store_val: |
| #endif |
| if (!(first_ch & 0x80)) { /* unquoted $VAR */ |
| debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val, output->o_escape); |
| if (val) { |
| /* unquoted var's contents should be globbed, so don't escape */ |
| smallint sv = output->o_escape; |
| output->o_escape = 0; |
| n = expand_on_ifs(output, n, val); |
| val = NULL; |
| output->o_escape = sv; |
| } |
| } else { /* quoted $VAR, val will be appended below */ |
| debug_printf_expand("quoted '%s', output->o_escape:%d\n", val, output->o_escape); |
| } |
| } /* default: */ |
| } /* switch (char after <SPECIAL_VAR_SYMBOL>) */ |
| |
| if (val) { |
| o_addQstr(output, val, strlen(val)); |
| } |
| free(dyn_val); |
| /* Do the check to avoid writing to a const string */ |
| if (*p != SPECIAL_VAR_SYMBOL) |
| *p = SPECIAL_VAR_SYMBOL; |
| |
| #if ENABLE_HUSH_TICK |
| o_free(&subst_result); |
| #endif |
| arg = ++p; |
| } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */ |
| |
| if (arg[0]) { |
| debug_print_list("expand_vars_to_list[a]", output, n); |
| /* this part is literal, and it was already pre-quoted |
| * if needed (much earlier), do not use o_addQstr here! */ |
| o_addstr_with_NUL(output, arg); |
| debug_print_list("expand_vars_to_list[b]", output, n); |
| } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */ |
| && !(ored_ch & 0x80) /* and all vars were not quoted. */ |
| ) { |
| n--; |
| /* allow to reuse list[n] later without re-growth */ |
| output->has_empty_slot = 1; |
| } else { |
| o_addchr(output, '\0'); |
| } |
| return n; |
| } |
| |
| static char **expand_variables(char **argv, int or_mask) |
| { |
| int n; |
| char **list; |
| char **v; |
| o_string output = NULL_O_STRING; |
| |
| if (or_mask & 0x100) { |
| output.o_escape = 1; /* protect against globbing for "$var" */ |
| /* (unquoted $var will temporarily switch it off) */ |
| output.o_glob = 1; |
| } |
| |
| n = 0; |
| v = argv; |
| while (*v) { |
| n = expand_vars_to_list(&output, n, *v, (unsigned char)or_mask); |
| v++; |
| } |
| debug_print_list("expand_variables", &output, n); |
| |
| /* output.data (malloced in one block) gets returned in "list" */ |
| list = o_finalize_list(&output, n); |
| debug_print_strings("expand_variables[1]", list); |
| return list; |
| } |
| |
| static char **expand_strvec_to_strvec(char **argv) |
| { |
| return expand_variables(argv, 0x100); |
| } |
| |
| #if ENABLE_HUSH_BASH_COMPAT |
| static char **expand_strvec_to_strvec_singleword_noglob(char **argv) |
| { |
| return expand_variables(argv, 0x80); |
| } |
| #endif |
| |
| #ifdef CMD_SINGLEWORD_NOGLOB_COND |
| static char **expand_strvec_to_strvec_singleword_noglob_cond(char **argv) |
| { |
| int n; |
| char **list; |
| char **v; |
| o_string output = NULL_O_STRING; |
| |
| n = 0; |
| v = argv; |
| while (*v) { |
| int is_var = is_well_formed_var_name(*v, '='); |
| /* is_var * 0x80: singleword expansion for vars */ |
| n = expand_vars_to_list(&output, n, *v, is_var * 0x80); |
| |
| /* Subtle! expand_vars_to_list did not glob last word yet. |
| * It does this only when fed with further data. |
| * Therefore we set globbing flags AFTER it, not before: |
| */ |
| |
| /* if it is not recognizably abc=...; then: */ |
| output.o_escape = !is_var; /* protect against globbing for "$var" */ |
| /* (unquoted $var will temporarily switch it off) */ |
| output.o_glob = !is_var; /* and indeed do globbing */ |
| v++; |
| } |
| debug_print_list("expand_cond", &output, n); |
| |
| /* output.data (malloced in one block) gets returned in "list" */ |
| list = o_finalize_list(&output, n); |
| debug_print_strings("expand_cond[1]", list); |
| return list; |
| } |
| #endif |
| |
| /* Used for expansion of right hand of assignments */ |
| /* 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) |
| { |
| char *argv[2], **list; |
| |
| argv[0] = (char*)str; |
| argv[1] = NULL; |
| list = expand_variables(argv, 0x80); /* 0x80: singleword expansion */ |
| if (HUSH_DEBUG) |
| if (!list[0] || list[1]) |
| bb_error_msg_and_die("BUG in varexp2"); |
| /* actually, just move string 2*sizeof(char*) bytes back */ |
| overlapping_strcpy((char*)list, list[0]); |
| unbackslash((char*)list); |
| debug_printf_expand("string_to_string='%s'\n", (char*)list); |
| return (char*)list; |
| } |
| |
| /* Used for "eval" builtin */ |
| static char* expand_strvec_to_string(char **argv) |
| { |
| char **list; |
| |
| list = expand_variables(argv, 0x80); |
| /* 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]); |
| debug_printf_expand("strvec_to_string='%s'\n", (char*)list); |
| return (char*)list; |
| } |
| |
| static char **expand_assignments(char **argv, int count) |
| { |
| int i; |
| char **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])); |
| } |
| return p; |
| } |
| |
| |
| #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). |
| */ |
| 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. |
| */ |
| if (!G.traps && !(G.non_DFL_mask & SPECIAL_INTERACTIVE_SIGS)) |
| return; /* already no traps and no SPECIAL_INTERACTIVE_SIGS */ |
| |
| /* Switching off SPECIAL_INTERACTIVE_SIGS. |
| * Stupid. It can be done with *single* &= op, but we can't use |
| * the fact that G.blocked_set is implemented as a bitmask |
| * in libc... */ |
| mask = (SPECIAL_INTERACTIVE_SIGS >> 1); |
| sig = 1; |
| while (1) { |
| if (mask & 1) { |
| /* Careful. Only if no trap or trap is not "" */ |
| if (!G.traps || !G.traps[sig] || G.traps[sig][0]) |
| sigdelset(&G.blocked_set, sig); |
| } |
| mask >>= 1; |
| if (!mask) |
| break; |
| sig++; |
| } |
| /* Our homegrown sig mask is saner to work with :) */ |
| G.non_DFL_mask &= ~SPECIAL_INTERACTIVE_SIGS; |
| |
| /* Resetting all traps to default except empty ones */ |
| mask = G.non_DFL_mask; |
| if (G.traps) for (sig = 0; sig < NSIG; sig++, mask >>= 1) { |
| if (!G.traps[sig] || !G.traps[sig][0]) |
| continue; |
| free(G.traps[sig]); |
| G.traps[sig] = NULL; |
| /* There is no signal for 0 (EXIT) */ |
| if (sig == 0) |
| continue; |
| /* There was a trap handler, we just removed it. |
| * But if sig still has non-DFL handling, |
| * we should not unblock the sig. */ |
| if (mask & 1) |
| continue; |
| sigdelset(&G.blocked_set, sig); |
| } |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| } |
| |
| #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 (cur->varstr == hush_version_str) |
| 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. |
| * Even if we would use signal handlers instead of signal masking |
| * in order to implement trap handling, |
| * exec syscall below resets signals to SIG_DFL for us. |
| */ |
| *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); |
| sigprocmask(SIG_SETMASK, &G.inherited_set, NULL); |
| 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_error_msg_and_die("can't re-execute the shell"); |
| } |
| #endif /* !BB_MMU */ |
| |
| |
| 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 = expand_pseudo_dquoted(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 = vfork(); |
| if (pid < 0) |
| bb_perror_msg_and_die("vfork"); |
| if (pid == 0) { |
| /* child */ |
| disable_restore_tty_pgrp_on_exit(); |
| pid = BB_MMU ? fork() : vfork(); |
| if (pid < 0) |
| bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); |
| 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 */ |
| } |
| |
| /* squirrel != NULL means we squirrel away copies of stdin, stdout, |
| * and stderr if they are redirected. */ |
| static int setup_redirects(struct command *prog, int squirrel[]) |
| { |
| int openfd, mode; |
| struct redir_struct *redir; |
| |
| for (redir = prog->redirects; redir; redir = redir->next) { |
| if (redir->rd_type == REDIRECT_HEREDOC2) { |
| /* rd_fd<<HERE case */ |
| if (squirrel && redir->rd_fd < 3 |
| && squirrel[redir->rd_fd] < 0 |
| ) { |
| squirrel[redir->rd_fd] = dup(redir->rd_fd); |
| } |
| /* for REDIRECT_HEREDOC2, rd_filename holds _contents_ |
| * of the heredoc */ |
| debug_printf_parse("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; |
| if (redir->rd_filename == NULL) { |
| /* Something went wrong in the parse. |
| * Pretend it didn't happen */ |
| bb_error_msg("bug in redirect parse"); |
| continue; |
| } |
| mode = redir_table[redir->rd_type].mode; |
| p = expand_string_to_string(redir->rd_filename); |
| openfd = open_or_warn(p, mode); |
| free(p); |
| if (openfd < 0) { |
| /* this could get lost if stderr has been redirected, but |
| * bash and ash both lose it as well (though zsh doesn't!) */ |
| //what the above comment tries to say? |
| return 1; |
| } |
| } else { |
| /* rd_fd<*>rd_dup or rd_fd<*>- cases */ |
| openfd = redir->rd_dup; |
| } |
| |
| if (openfd != redir->rd_fd) { |
| if (squirrel && redir->rd_fd < 3 |
| && squirrel[redir->rd_fd] < 0 |
| ) { |
| squirrel[redir->rd_fd] = dup(redir->rd_fd); |
| } |
| if (openfd == REDIRFD_CLOSE) { |
| /* "n>-" means "close me" */ |
| close(redir->rd_fd); |
| } else { |
| xdup2(openfd, redir->rd_fd); |
| if (redir->rd_dup == REDIRFD_TO_FILE) |
| close(openfd); |
| } |
| } |
| } |
| return 0; |
| } |
| |
| static void restore_redirects(int squirrel[]) |
| { |
| int i, fd; |
| for (i = 0; i < 3; i++) { |
| fd = squirrel[i]; |
| if (fd != -1) { |
| /* We simply die on error */ |
| xmove_fd(fd, i); |
| } |
| } |
| } |
| |
| |
| static void free_pipe_list(struct pipe *head); |
| |
| /* Return code is the exit status of the pipe */ |
| static void free_pipe(struct pipe *pi) |
| { |
| char **p; |
| struct command *command; |
| struct redir_struct *r, *rnext; |
| int a, i; |
| |
| if (pi->stopped_cmds > 0) /* why? */ |
| return; |
| debug_printf_clean("run pipe: (pid %d)\n", getpid()); |
| for (i = 0; i < pi->num_cmds; i++) { |
| command = &pi->cmds[i]; |
| debug_printf_clean(" command %d:\n", i); |
| if (command->argv) { |
| 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 |
| } |
| |
| static void free_pipe_list(struct pipe *head) |
| { |
| struct pipe *pi, *next; |
| |
| for (pi = head; pi; pi = next) { |
| #if HAS_KEYWORDS |
| debug_printf_clean(" pipe reserved word %d\n", pi->res_word); |
| #endif |
| free_pipe(pi); |
| debug_printf_clean("pipe followup code %d\n", pi->followup); |
| next = pi->next; |
| /*pi->next = NULL;*/ |
| free(pi); |
| } |
| } |
| |
| |
| static int run_list(struct pipe *pi); |
| #if BB_MMU |
| #define parse_stream(pstring, input, end_trigger) \ |
| parse_stream(input, end_trigger) |
| #endif |
| static struct pipe *parse_stream(char **pstring, |
| struct in_str *input, |
| int end_trigger); |
| static void parse_and_run_string(const char *s); |
| |
| |
| 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->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_FUNCTIONS |
| static struct function **find_function_slot(const char *name) |
| { |
| struct function **funcpp = &G.top_func; |
| while (*funcpp) { |
| if (strcmp(name, (*funcpp)->name) == 0) { |
| break; |
| } |
| funcpp = &(*funcpp)->next; |
| } |
| return funcpp; |
| } |
| |
| static const struct function *find_function(const char *name) |
| { |
| const struct function *funcp = *find_function_slot(name); |
| if (funcp) |
| debug_printf_exec("found function '%s'\n", 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; |
| } |
| |
| 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); |
| } |
| } |
| |
| # 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 = 1; |
| |
| argv[0] = G.global_argv[0]; |
| G.global_argv = argv; |
| while (*++argv) |
| n++; |
| G.global_argc = n; |
| /* On MMU, funcp->body is always non-NULL */ |
| n = run_list(funcp->body); |
| fflush_all(); |
| _exit(n); |
| # else |
| 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; |
| # if ENABLE_HUSH_LOCAL |
| G.func_nest_level++; |
| # endif |
| |
| /* 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 ENABLE_HUSH_LOCAL |
| { |
| struct variable *var; |
| struct variable **var_pp; |
| |
| var_pp = &G.top_var; |
| while ((var = *var_pp) != NULL) { |
| if (var->func_nest_level < G.func_nest_level) { |
| var_pp = &var->next; |
| continue; |
| } |
| /* Unexport */ |
| if (var->flg_export) |
| bb_unsetenv(var->varstr); |
| /* Remove from global list */ |
| *var_pp = var->next; |
| /* Free */ |
| if (!var->max_len) |
| free(var->varstr); |
| free(var); |
| } |
| G.func_nest_level--; |
| } |
| # endif |
| G.flag_return_in_progress = sv_flg; |
| |
| 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 = x->function(argv); |
| fflush_all(); |
| _exit(rcode); |
| #else |
| /* 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) |
| { |
| debug_printf_exec("execing '%s'\n", argv[0]); |
| sigprocmask(SIG_SETMASK, &G.inherited_set, NULL); |
| execvp(argv[0], argv); |
| bb_perror_msg("can't execute '%s'", argv[0]); |
| _exit(127); /* bash compat */ |
| } |
| |
| #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) |
| { |
| char **new_env; |
| |
| /* Case when we are here: ... | var=val | ... */ |
| if (!argv[assignment_cnt]) |
| _exit(EXIT_SUCCESS); |
| |
| new_env = expand_assignments(argv, assignment_cnt); |
| #if BB_MMU |
| set_vars_and_save_old(new_env); |
| free(new_env); /* optional */ |
| /* we can also destroy set_vars_and_save_old's return value, |
| * to save memory */ |
| #else |
| nommu_save->new_env = new_env; |
| nommu_save->old_vars = set_vars_and_save_old(new_env); |
| #endif |
| if (argv_expanded) { |
| argv = argv_expanded; |
| } else { |
| argv = expand_strvec_to_strvec(argv + assignment_cnt); |
| #if !BB_MMU |
| nommu_save->argv = argv; |
| #endif |
| } |
| |
| #if ENABLE_FEATURE_SH_STANDALONE || BB_MMU |
| if (strchr(argv[0], '/') != NULL) |
| goto skip; |
| #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. |
| */ |
| { |
| /* 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. */ |
| const struct built_in_command *x; |
| x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]); |
| if (x) { |
| exec_builtin(&nommu_save->argv_from_re_execing, x, argv); |
| } |
| } |
| #if ENABLE_HUSH_FUNCTIONS |
| /* Check if the command matches any functions */ |
| { |
| const struct function *funcp = find_function(argv[0]); |
| if (funcp) { |
| exec_function(&nommu_save->argv_from_re_execing, funcp, argv); |
| } |
| } |
| #endif |
| |
| #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 BB_MMU /* see above why on NOMMU it is not allowed */ |
| if (APPLET_IS_NOEXEC(a)) { |
| debug_printf_exec("running applet '%s'\n", argv[0]); |
| run_applet_no_and_exit(a, argv); |
| } |
| # endif |
| /* Re-exec ourselves */ |
| debug_printf_exec("re-execing applet '%s'\n", argv[0]); |
| sigprocmask(SIG_SETMASK, &G.inherited_set, NULL); |
| 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 |
| 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 (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 || !argv[0]) { |
| 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 { |
| len = strlen(*argv); |
| memcpy(p, *argv, len); |
| p += len; |
| *p++ = ' '; |
| } while (*++argv); |
| p[-1] = '\0'; |
| return pi->cmdtext; |
| } |
| |
| static void insert_bg_job(struct pipe *pi) |
| { |
| struct pipe *job, **jobp; |
| int i; |
| |
| /* Linear search for the ID of the job to use */ |
| pi->jobid = 1; |
| for (job = G.job_list; job; job = job->next) |
| if (job->jobid >= pi->jobid) |
| pi->jobid = job->jobid + 1; |
| |
| /* Add job to the list of running jobs */ |
| jobp = &G.job_list; |
| while ((job = *jobp) != NULL) |
| jobp = &job->next; |
| job = *jobp = xmalloc(sizeof(*job)); |
| |
| *job = *pi; /* physical copy */ |
| 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("[%d] %d %s\n", job->jobid, job->cmds[0].pid, job->cmdtext); |
| /* Last command's pid goes to $! */ |
| G.last_bg_pid = job->cmds[job->num_cmds - 1].pid; |
| G.last_jobid = job->jobid; |
| } |
| |
| static void remove_bg_job(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; |
| } |
| if (G.job_list) |
| G.last_jobid = G.job_list->jobid; |
| else |
| G.last_jobid = 0; |
| } |
| |
| /* Remove a backgrounded job */ |
| static void delete_finished_bg_job(struct pipe *pi) |
| { |
| remove_bg_job(pi); |
| pi->stopped_cmds = 0; |
| free_pipe(pi); |
| free(pi); |
| } |
| #endif /* JOB */ |
| |
| /* Check to see if any processes have exited -- if they |
| * have, figure out why and see if a job has completed */ |
| static int checkjobs(struct pipe* fg_pipe) |
| { |
| int attributes; |
| int status; |
| #if ENABLE_HUSH_JOB |
| struct pipe *pi; |
| #endif |
| pid_t childpid; |
| 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] |
| */ |
| wait_more: |
| while (1) { |
| int i; |
| int dead; |
| |
| #if ENABLE_HUSH_FAST |
| i = G.count_SIGCHLD; |
| #endif |
| childpid = waitpid(-1, &status, attributes); |
| if (childpid <= 0) { |
| if (childpid && errno != ECHILD) |
| bb_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 |
| break; |
| } |
| 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 fg pipe? */ |
| if (fg_pipe) { |
| for (i = 0; i < fg_pipe->num_cmds; i++) { |
| debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid); |
| if (fg_pipe->cmds[i].pid != childpid) |
| continue; |
| if (dead) { |
| fg_pipe->cmds[i].pid = 0; |
| fg_pipe->alive_cmds--; |
| if (i == fg_pipe->num_cmds - 1) { |
| /* last process gives overall exitstatus */ |
| rcode = WEXITSTATUS(status); |
| /* bash prints killer signal's name for *last* |
| * process in pipe (prints just newline for SIGINT). |
| * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT) |
| */ |
| if (WIFSIGNALED(status)) { |
| int sig = WTERMSIG(status); |
| printf("%s\n", sig == SIGINT ? "" : get_signame(sig)); |
| /* TODO: MIPS has 128 sigs (1..128), what if sig==128 here? |
| * Maybe we need to use sig | 128? */ |
| rcode = sig + 128; |
| } |
| IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;) |
| } |
| } else { |
| fg_pipe->cmds[i].is_stopped = 1; |
| fg_pipe->stopped_cmds++; |
| } |
| debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n", |
| fg_pipe->alive_cmds, fg_pipe->stopped_cmds); |
| if (fg_pipe->alive_cmds - fg_pipe->stopped_cmds <= 0) { |
| /* All processes in fg pipe have exited or stopped */ |
| /* 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) |
| insert_bg_job(fg_pipe); |
| #endif |
| return rcode; |
| } |
| if (!fg_pipe->alive_cmds) |
| return rcode; |
| } |
| /* There are still running processes in the fg pipe */ |
| goto wait_more; /* do waitpid again */ |
| } |
| /* it wasnt fg_pipe, look for process in bg pipes */ |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* We 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); |
| continue; /* do waitpid again */ |
| |
| found_pi_and_prognum: |
| if (dead) { |
| /* child exited */ |
| pi->cmds[i].pid = 0; |
| pi->alive_cmds--; |
| if (!pi->alive_cmds) { |
| if (G_interactive_fd) |
| printf(JOB_STATUS_FORMAT, pi->jobid, |
| "Done", pi->cmdtext); |
| delete_finished_bg_job(pi); |
| } |
| } else { |
| /* child stopped */ |
| pi->cmds[i].is_stopped = 1; |
| pi->stopped_cmds++; |
| } |
| #endif |
| } /* 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); |
| 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 [do we do this?], |
| * 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 ) [&] |
| */ |
| static NOINLINE int run_pipe(struct pipe *pi) |
| { |
| static const char *const null_ptr = NULL; |
| int i; |
| int nextin; |
| struct command *command; |
| char **argv_expanded; |
| char **argv; |
| char *p; |
| /* it is not always needed, but we aim to smaller code */ |
| int squirrel[] = { -1, -1, -1 }; |
| int rcode; |
| |
| debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds); |
| debug_enter(); |
| |
| 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("non-subshell group\n"); |
| rcode = 1; /* exitcode if redir failed */ |
| if (setup_redirects(command, squirrel) == 0) { |
| debug_printf_exec(": run_list\n"); |
| 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 ENABLE_HUSH_FUNCTIONS |
| const struct function *funcp; |
| #else |
| enum { funcp = 0 }; |
| #endif |
| char **new_env = NULL; |
| struct variable *old_vars = NULL; |
| |
| if (argv[command->assignment_cnt] == NULL) { |
| /* Assignments, but no command */ |
| /* Ensure redirects take effect. Try "a=t >file" */ |
| rcode = setup_redirects(command, squirrel); |
| restore_redirects(squirrel); |
| /* Set shell variables */ |
| while (*argv) { |
| p = expand_string_to_string(*argv); |
| debug_printf_exec("set shell var:'%s'->'%s'\n", |
| *argv, p); |
| set_local_var(p, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0); |
| argv++; |
| } |
| /* Do we need to flag set_local_var() errors? |
| * "assignment to readonly var" and "putenv error" |
| */ |
| 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 (0) {} |
| #if ENABLE_HUSH_BASH_COMPAT |
| else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) { |
| argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt); |
| } |
| #endif |
| #ifdef CMD_SINGLEWORD_NOGLOB_COND |
| else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB_COND) { |
| argv_expanded = expand_strvec_to_strvec_singleword_noglob_cond(argv + command->assignment_cnt); |
| |
| } |
| #endif |
| else { |
| 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); |
| debug_leave(); |
| return G.last_exitcode; |
| } |
| |
| x = find_builtin(argv_expanded[0]); |
| #if ENABLE_HUSH_FUNCTIONS |
| funcp = NULL; |
| if (!x) |
| funcp = find_function(argv_expanded[0]); |
| #endif |
| if (x || funcp) { |
| if (!funcp) { |
| if (x->function == builtin_exec && argv_expanded[1] == NULL) { |
| debug_printf("exec with redirects only\n"); |
| rcode = setup_redirects(command, NULL); |
| goto clean_up_and_ret1; |
| } |
| } |
| /* setup_redirects acts on file descriptors, not FILEs. |
| * This is perfect for work that comes after exec(). |
| * Is it really safe for inline use? Experimentally, |
| * things seem to work. */ |
| rcode = setup_redirects(command, squirrel); |
| if (rcode == 0) { |
| new_env = expand_assignments(argv, command->assignment_cnt); |
| old_vars = set_vars_and_save_old(new_env); |
| if (!funcp) { |
| debug_printf_exec(": builtin '%s' '%s'...\n", |
| x->cmd, argv_expanded[1]); |
| rcode = x->function(argv_expanded) & 0xff; |
| fflush_all(); |
| } |
| #if ENABLE_HUSH_FUNCTIONS |
| else { |
| # if ENABLE_HUSH_LOCAL |
| struct variable **sv; |
| sv = G.shadowed_vars_pp; |
| G.shadowed_vars_pp = &old_vars; |
| # endif |
| debug_printf_exec(": function '%s' '%s'...\n", |
| funcp->name, argv_expanded[1]); |
| rcode = run_function(funcp, argv_expanded) & 0xff; |
| # if ENABLE_HUSH_LOCAL |
| G.shadowed_vars_pp = sv; |
| # endif |
| } |
| #endif |
| } |
| #if ENABLE_FEATURE_SH_STANDALONE |
| clean_up_and_ret: |
| #endif |
| restore_redirects(squirrel); |
| unset_vars(new_env); |
| add_vars(old_vars); |
| clean_up_and_ret1: |
| 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; |
| } |
| |
| #if ENABLE_FEATURE_SH_STANDALONE |
| i = find_applet_by_name(argv_expanded[0]); |
| if (i >= 0 && APPLET_IS_NOFORK(i)) { |
| rcode = setup_redirects(command, squirrel); |
| if (rcode == 0) { |
| new_env = expand_assignments(argv, command->assignment_cnt); |
| old_vars = set_vars_and_save_old(new_env); |
| debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", |
| argv_expanded[0], argv_expanded[1]); |
| rcode = run_nofork_applet(i, argv_expanded); |
| } |
| goto clean_up_and_ret; |
| } |
| #endif |
| /* It is neither builtin nor applet. We must fork. */ |
| } |
| |
| 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; |
| nextin = 0; |
| |
| for (i = 0; i < pi->num_cmds; i++) { |
| struct fd_pair pipefds; |
| #if !BB_MMU |
| volatile nommu_save_t nommu_save; |
| nommu_save.new_env = NULL; |
| nommu_save.old_vars = NULL; |
| nommu_save.argv = NULL; |
| nommu_save.argv_from_re_execing = NULL; |
| #endif |
| command = &(pi->cmds[i]); |
| 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 ((i + 1) < pi->num_cmds) |
| xpiped_pair(pipefds); |
| |
| 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(nextin, 0); |
| } |
| xmove_fd(pipefds.wr, 1); |
| if (pipefds.rd > 1) |
| close(pipefds.rd); |
| /* Like bash, explicit redirects override pipes, |
| * and the pipe fd is available for dup'ing. */ |
| if (setup_redirects(command, NULL)) |
| _exit(1); |
| |
| /* Restore default handlers just prior to exec */ |
| /*signal(SIGCHLD, SIG_DFL); - so far we don't have any handlers */ |
| |
| /* 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); |
| unset_vars(nommu_save.new_env); |
| 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_perror_msg(BB_MMU ? "fork" : "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 (i) |
| close(nextin); |
| if ((i + 1) < pi->num_cmds) |
| close(pipefds.wr); |
| /* Pass read (output) pipe end to next iteration */ |
| nextin = 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; |
| } |
| |
| #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) { |
| fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "", |
| pin, 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; |
| |
| fprintf(stderr, "%*s cmd %d assignment_cnt:%d", |
| lvl*2, "", prn, |
| command->assignment_cnt); |
| if (command->group) { |
| fprintf(stderr, " 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) { |
| fprintf(stderr, " '%s'", *argv); |
| argv++; |
| } |
| fprintf(stderr, "\n"); |
| prn++; |
| } |
| pi = pi->next; |
| pin++; |
| } |
| } |
| #endif /* debug_print_tree */ |
| |
| /* 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; /* enum reserved_style */ |
| 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" */ |
| for (struct pipe *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) { |
| if (G.flag_SIGINT) |
| 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); |
| #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; |
| 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: "$@" */ |
| char **vals; |
| |
| vals = (char**)encoded_dollar_at_argv; |
| if (pi->next->res_word == RES_IN) { |
| /* if no variable values after "in" we skip "for" */ |
| if (!pi->next->cmds[0].argv) { |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n"); |
| break; |
| } |
| vals = pi->next->cmds[0].argv; |
| } /* else: "for var; do..." -> assume "$@" 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++), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 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) { |
| case_word = expand_strvec_to_string(pi->cmds->argv); |
| continue; |
| } |
| if (rword == RES_MATCH) { |
| char **argv; |
| |
| 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 = expand_string_to_string(*argv); |
| /* TODO: which FNM_xxx flags to use? */ |
| cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0); |
| free(pattern); |
| if (cond_code == 0) { /* match! we will execute this branch */ |
| free(case_word); /* make future "word)" stop */ |
| case_word = NULL; |
| break; |
| } |
| argv++; |
| } |
| continue; |
| } |
| if (rword == RES_CASE_BODY) { /* inside of a case branch */ |
| if (cond_code != 0) |
| continue; /* not matched yet, skip this pipe */ |
| } |
| #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); |
| { |
| int r; |
| #if ENABLE_HUSH_LOOPS |
| G.flag_break_continue = 0; |
| #endif |
| rcode = r = run_pipe(pi); /* NB: rcode is a smallint */ |
| if (r != -1) { |
| /* We ran a builtin, function, or group. |
| * rcode is already known |
| * and we don't need to wait for anything. */ |
| G.last_exitcode = rcode; |
| debug_printf_exec(": builtin/func exitcode %d\n", rcode); |
| check_and_run_traps(0); |
| #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) |
| goto check_jobs_and_break; |
| /* "continue": simulate end of loop */ |
| rword = RES_DONE; |
| continue; |
| } |
| #endif |
| #if ENABLE_HUSH_FUNCTIONS |
| if (G.flag_return_in_progress == 1) { |
| /* same as "goto check_jobs_and_break" */ |
| checkjobs(NULL); |
| break; |
| } |
| #endif |
| } 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 */ |
| check_and_run_traps(0); |
| #if ENABLE_HUSH_JOB |
| if (G.run_list_level == 1) |
| insert_bg_job(pi); |
| #endif |
| G.last_exitcode = rcode = EXIT_SUCCESS; |
| debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n"); |
| } 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); |
| check_and_run_traps(0); |
| } else |
| #endif |
| { /* This one just waits for completion */ |
| rcode = checkjobs(pi); |
| debug_printf_exec(": checkjobs exitcode %d\n", rcode); |
| check_and_run_traps(0); |
| } |
| G.last_exitcode = rcode; |
| } |
| } |
| |
| /* Analyze how result affects subsequent commands */ |
| #if ENABLE_HUSH_IF |
| if (rword == RES_IF || rword == RES_ELIF) |
| cond_code = rcode; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| /* Beware of "while false; true; do ..."! */ |
| if (pi->next && pi->next->res_word == RES_DO) { |
| 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"); |
| goto check_jobs_and_break; |
| } |
| } |
| if (rword == RES_UNTIL) { |
| if (!rcode) { |
| debug_printf_exec(": until expr is true: breaking\n"); |
| check_jobs_and_break: |
| checkjobs(NULL); |
| break; |
| } |
| } |
| } |
| #endif |
| |
| check_jobs_and_continue: |
| checkjobs(NULL); |
| } /* 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.fake_mode) { |
| 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 struct pipe *new_pipe(void) |
| { |
| struct pipe *pi; |
| pi = xzalloc(sizeof(struct pipe)); |
| /*pi->followup = 0; - deliberately invalid value */ |
| /*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 (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)); |
| 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); |
| ctx->pipe->followup = type; |
| #if HAS_KEYWORDS |
| ctx->pipe->pi_inverted = ctx->ctx_inverted; |
| ctx->ctx_inverted = 0; |
| ctx->pipe->res_word = ctx->ctx_res_w; |
| #endif |
| |
| /* 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)); |
| 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; |
| int 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[] = { |
| # if ENABLE_HUSH_IF |
| { "!", RES_NONE, NOT_ASSIGNMENT , 0 }, |
| { "if", RES_IF, WORD_IS_KEYWORD, FLAG_THEN | FLAG_START }, |
| { "then", RES_THEN, WORD_IS_KEYWORD, FLAG_ELIF | FLAG_ELSE | FLAG_FI }, |
| { "elif", RES_ELIF, WORD_IS_KEYWORD, FLAG_THEN }, |
| { "else", RES_ELSE, WORD_IS_KEYWORD, 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, WORD_IS_KEYWORD, FLAG_DO | FLAG_START }, |
| { "until", RES_UNTIL, WORD_IS_KEYWORD, FLAG_DO | FLAG_START }, |
| { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO }, |
| { "do", RES_DO, WORD_IS_KEYWORD, 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 0: not a keyword, 1: keyword |
| */ |
| static int reserved_word(o_string *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 (word->o_quoted) |
| return 0; |
| r = match_reserved_word(word); |
| if (!r) |
| return 0; |
| |
| 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 1; |
| } |
| if (r->flag & FLAG_START) { |
| struct parse_context *old; |
| |
| old = xmalloc(sizeof(*old)); |
| debug_printf_parse("push stack %p\n", old); |
| *old = *ctx; /* physical copy */ |
| initialize_context(ctx); |
| ctx->stack = old; |
| } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) { |
| syntax_error_at(word->data); |
| ctx->ctx_res_w = RES_SNTX; |
| return 1; |
| } 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; |
| word->o_assignment = r->assignment_flag; |
| |
| 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 |
| o_addstr(&old->as_string, ctx->as_string.data); |
| o_free_unsafe(&ctx->as_string); |
| old->command->group_as_string = xstrdup(old->as_string.data); |
| debug_printf_parse("pop, remembering as:'%s'\n", |
| old->command->group_as_string); |
| # endif |
| *ctx = *old; /* physical copy */ |
| free(old); |
| } |
| return 1; |
| } |
| #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(o_string *word, struct parse_context *ctx) |
| { |
| struct command *command = ctx->command; |
| |
| debug_printf_parse("done_word entered: '%s' %p\n", word->data, command); |
| if (word->length == 0 && word->o_quoted == 0) { |
| 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://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html |
| * "2.7 Redirection |
| * ...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." |
| */ |
| ctx->pending_redirect->rd_filename = xstrdup(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 (word->o_quoted) { |
| ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED; |
| } |
| } |
| debug_printf_parse("word stored in rd_filename: '%s'\n", word->data); |
| ctx->pending_redirect = NULL; |
| } else { |
| /* If this word wasn't an assignment, next ones definitely |
| * can't be assignments. Even if they look like ones. */ |
| if (word->o_assignment != DEFINITELY_ASSIGNMENT |
| && word->o_assignment != WORD_IS_KEYWORD |
| ) { |
| word->o_assignment = NOT_ASSIGNMENT; |
| } else { |
| if (word->o_assignment == DEFINITELY_ASSIGNMENT) |
| command->assignment_cnt++; |
| word->o_assignment = MAYBE_ASSIGNMENT; |
| } |
| |
| #if HAS_KEYWORDS |
| # if ENABLE_HUSH_CASE |
| if (ctx->ctx_dsemicolon |
| && strcmp(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 (!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 |
| ) { |
| debug_printf_parse("checking '%s' for reserved-ness\n", word->data); |
| if (reserved_word(word, ctx)) { |
| o_reset_to_empty_unquoted(word); |
| debug_printf_parse("done_word return %d\n", |
| (ctx->ctx_res_w == RES_SNTX)); |
| return (ctx->ctx_res_w == RES_SNTX); |
| } |
| # ifdef CMD_SINGLEWORD_NOGLOB_COND |
| if (strcmp(word->data, "export") == 0 |
| # if ENABLE_HUSH_LOCAL |
| || strcmp(word->data, "local") == 0 |
| # endif |
| ) { |
| command->cmd_type = CMD_SINGLEWORD_NOGLOB_COND; |
| } else |
| # endif |
| # if ENABLE_HUSH_BASH_COMPAT |
| if (strcmp(word->data, "[[") == 0) { |
| command->cmd_type = CMD_SINGLEWORD_NOGLOB; |
| } |
| /* fall through */ |
| # endif |
| } |
| #endif |
| if (command->group) { |
| /* "{ echo foo; } echo bar" - bad */ |
| syntax_error_at(word->data); |
| debug_printf_parse("done_word return 1: syntax error, " |
| "groups and arglists don't mix\n"); |
| return 1; |
| } |
| if (word->o_quoted /* word had "xx" or 'xx' at least as part of it. */ |
| /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */ |
| && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL) |
| /* (otherwise it's known to be not empty and is already safe) */ |
| ) { |
| /* exclude "$@" - it can expand to no word despite "" */ |
| char *p = word->data; |
| while (p[0] == SPECIAL_VAR_SYMBOL |
| && (p[1] & 0x7f) == '@' |
| && p[2] == SPECIAL_VAR_SYMBOL |
| ) { |
| p += 3; |
| } |
| if (p == word->data || p[0] != '\0') { |
| /* saw no "$@", or not only "$@" but some |
| * real text is there too */ |
| /* insert "empty variable" reference, this makes |
| * e.g. "", $empty"" etc to not disappear */ |
| o_addchr(word, SPECIAL_VAR_SYMBOL); |
| o_addchr(word, SPECIAL_VAR_SYMBOL); |
| } |
| } |
| command->argv = add_string_to_strings(command->argv, xstrdup(word->data)); |
| debug_print_strings("word appended to argv", command->argv); |
| } |
| |
| #if ENABLE_HUSH_LOOPS |
| if (ctx->ctx_res_w == RES_FOR) { |
| if (word->o_quoted |
| || !is_well_formed_var_name(command->argv[0], '\0') |
| ) { |
| /* bash says just "not a valid identifier" */ |
| syntax_error("not a valid identifier 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(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_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(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(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 { |
| /* 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 ->o_quoted 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 skip_tabs) |
| { |
| o_string heredoc = NULL_O_STRING; |
| int past_EOL = 0; |
| int ch; |
| |
| goto jump_in; |
| while (1) { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| if (ch == '\n') { |
| if (strcmp(heredoc.data + past_EOL, word) == 0) { |
| heredoc.data[past_EOL] = '\0'; |
| debug_printf_parse("parsed heredoc '%s'\n", heredoc.data); |
| return heredoc.data; |
| } |
| do { |
| o_addchr(&heredoc, ch); |
| past_EOL = heredoc.length; |
| jump_in: |
| do { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| } while (skip_tabs && ch == '\t'); |
| } while (ch == '\n'); |
| } |
| if (ch == EOF) { |
| o_free_unsafe(&heredoc); |
| return NULL; |
| } |
| o_addchr(&heredoc, ch); |
| nommu_addchr(as_string, ch); |
| } |
| } |
| |
| /* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs |
| * and load them all. There should be exactly heredoc_cnt of them. |
| */ |
| static int fetch_heredocs(int heredoc_cnt, struct parse_context *ctx, struct in_str *input) |
| { |
| struct pipe *pi = ctx->list_head; |
| |
| while (pi && heredoc_cnt) { |
| int i; |
| struct command *cmd = pi->cmds; |
| |
| debug_printf_parse("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_parse("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(&ctx->as_string, input, |
| redir->rd_filename, redir->rd_dup & HEREDOC_SKIPTABS); |
| if (!p) { |
| syntax_error("unexpected EOF in here document"); |
| return 1; |
| } |
| free(redir->rd_filename); |
| redir->rd_filename = p; |
| heredoc_cnt--; |
| } |
| redir = redir->next; |
| } |
| cmd++; |
| } |
| pi = pi->next; |
| } |
| #if 0 |
| /* Should be 0. If it isn't, it's a parse error */ |
| if (heredoc_cnt) |
| bb_error_msg_and_die("heredoc BUG 2"); |
| #endif |
| return 0; |
| } |
| |
| |
| #if ENABLE_HUSH_TICK |
| static FILE *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 ? fork() : vfork(); |
| if (pid < 0) |
| bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); |
| |
| 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); |
| CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */ |
| close(channel[0]); /* NB: close _first_, then move fd! */ |
| xmove_fd(channel[1], 1); |
| /* Prevent it from trying to handle ctrl-z etc */ |
| IF_HUSH_JOB(G.run_list_level = 1;) |
| /* 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 (strncmp(s, "trap", 4) == 0 && (*skip_whitespace(s + 4) == '\0')) |
| { |
| static const char *const argv[] = { NULL, NULL }; |
| builtin_trap((char**)argv); |
| exit(0); /* not _exit() - we need to fflush */ |
| } |
| # if BB_MMU |
| reset_traps_to_defaults(); |
| 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]); |
| close_on_exec_on(channel[0]); |
| return xfdopen_for_read(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; |
| struct in_str pipe_str; |
| pid_t pid; |
| int status, ch, eol_cnt; |
| |
| fp = generate_stream_from_string(s, &pid); |
| |
| /* Now send results of command back into original context */ |
| setup_file_in_str(&pipe_str, fp); |
| eol_cnt = 0; |
| while ((ch = i_getch(&pipe_str)) != EOF) { |
| 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 */ |
| |
| #if !ENABLE_HUSH_FUNCTIONS |
| #define parse_group(dest, ctx, input, ch) \ |
| parse_group(ctx, input, ch) |
| #endif |
| static int parse_group(o_string *dest, struct parse_context *ctx, |
| struct in_str *input, int ch) |
| { |
| /* dest contains characters seen prior to ( or {. |
| * Typically it's empty, but for function defs, |
| * it contains function name (without '()'). */ |
| struct pipe *pipe_list; |
| int endch; |
| struct command *command = ctx->command; |
| |
| debug_printf_parse("parse_group entered\n"); |
| #if ENABLE_HUSH_FUNCTIONS |
| if (ch == '(' && !dest->o_quoted) { |
| if (dest->length) |
| if (done_word(dest, 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 != '{') { |
| 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]{... */ |
| || dest->length /* word{... */ |
| || dest->o_quoted /* ""{... */ |
| ) { |
| syntax_error(NULL); |
| debug_printf_parse("parse_group return 1: " |
| "syntax error, groups and arglists don't mix\n"); |
| return 1; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_FUNCTIONS |
| skip: |
| #endif |
| endch = '}'; |
| if (ch == '(') { |
| endch = ')'; |
| command->cmd_type = CMD_SUBSHELL; |
| } else { |
| /* bash does not allow "{echo...", requires whitespace */ |
| ch = i_getch(input); |
| if (ch != ' ' && ch != '\t' && ch != '\n') { |
| syntax_error_unexpected_ch(ch); |
| return 1; |
| } |
| nommu_addchr(&ctx->as_string, ch); |
| } |
| |
| { |
| #if !BB_MMU |
| char *as_string = NULL; |
| #endif |
| pipe_list = parse_stream(&as_string, input, endch); |
| #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); |
| #endif |
| debug_printf_parse("parse_group return 1: " |
| "parse_stream returned %p\n", pipe_list); |
| return 1; |
| } |
| command->group = pipe_list; |
| #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 |
| } |
| debug_printf_parse("parse_group return 0\n"); |
| return 0; |
| /* command remains "open", available for possible redirects */ |
| } |
| |
| #if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT |
| /* Subroutines for copying $(...) and `...` things */ |
| static void add_till_backquote(o_string *dest, struct in_str *input); |
| /* '...' */ |
| static void add_till_single_quote(o_string *dest, struct in_str *input) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| /*xfunc_die(); - redundant */ |
| } |
| if (ch == '\'') |
| return; |
| o_addchr(dest, ch); |
| } |
| } |
| /* "...\"...`..`...." - do we need to handle "...$(..)..." too? */ |
| static void 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('"'); |
| /*xfunc_die(); - redundant */ |
| } |
| if (ch == '"') |
| return; |
| if (ch == '\\') { /* \x. Copy both chars. */ |
| o_addchr(dest, ch); |
| ch = i_getch(input); |
| } |
| o_addchr(dest, ch); |
| if (ch == '`') { |
| add_till_backquote(dest, input); |
| 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 $(command) |
| * form, or a quoted string, undefined results occur. A single-quoted |
| * or double-quoted string that begins, but does not end, within the |
| * "`...`" sequence produces undefined results." |
| * Example Output |
| * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST |
| */ |
| static void add_till_backquote(o_string *dest, struct in_str *input) |
| { |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('`'); |
| /*xfunc_die(); - redundant */ |
| } |
| if (ch == '`') |
| return; |
| if (ch == '\\') { |
| /* \x. Copy both chars unless it is \` */ |
| int ch2 = i_getch(input); |
| if (ch2 == EOF) { |
| syntax_error_unterm_ch('`'); |
| /*xfunc_die(); - redundant */ |
| } |
| if (ch2 != '`' && ch2 != '$' && ch2 != '\\') |
| o_addchr(dest, ch); |
| ch = ch2; |
| } |
| 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 |
| */ |
| static void add_till_closing_paren(o_string *dest, struct in_str *input, bool dbl) |
| { |
| int count = 0; |
| while (1) { |
| int ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch(')'); |
| /*xfunc_die(); - redundant */ |
| } |
| if (ch == '(') |
| count++; |
| if (ch == ')') { |
| if (--count < 0) { |
| if (!dbl) |
| break; |
| if (i_peek(input) == ')') { |
| i_getch(input); |
| break; |
| } |
| } |
| } |
| o_addchr(dest, ch); |
| if (ch == '\'') { |
| add_till_single_quote(dest, input); |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '"') { |
| add_till_double_quote(dest, input); |
| o_addchr(dest, ch); |
| continue; |
| } |
| if (ch == '\\') { |
| /* \x. Copy verbatim. Important for \(, \) */ |
| ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch(')'); |
| /*xfunc_die(); - redundant */ |
| } |
| o_addchr(dest, ch); |
| continue; |
| } |
| } |
| } |
| #endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT */ |
| |
| /* Return code: 0 for OK, 1 for syntax error */ |
| #if BB_MMU |
| #define handle_dollar(as_string, dest, input) \ |
| handle_dollar(dest, input) |
| #endif |
| static int handle_dollar(o_string *as_string, |
| o_string *dest, |
| struct in_str *input) |
| { |
| int ch = i_peek(input); /* first character after the $ */ |
| unsigned char quote_mask = dest->o_escape ? 0x80 : 0; |
| |
| debug_printf_parse("handle_dollar entered: ch='%c'\n", ch); |
| if (isalpha(ch)) { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| make_var: |
| 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(input); |
| if (!isalnum(ch) && ch != '_') |
| 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 */ |
| goto make_one_char_var; |
| case '{': { |
| bool first_char, all_digits; |
| int expansion; |
| |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| |
| /* TODO: maybe someone will try to escape the '}' */ |
| expansion = 0; |
| first_char = true; |
| all_digits = false; |
| while (1) { |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| if (ch == '}') { |
| break; |
| } |
| |
| if (first_char) { |
| if (ch == '#') { |
| /* ${#var}: length of var contents */ |
| goto char_ok; |
| } |
| if (isdigit(ch)) { |
| all_digits = true; |
| goto char_ok; |
| } |
| /* They're being verbose and doing ${?} */ |
| if (i_peek(input) == '}' && strchr("$!?#*@_", ch)) |
| goto char_ok; |
| } |
| |
| if (expansion < 2 |
| && ( (all_digits && !isdigit(ch)) |
| || (!all_digits && !isalnum(ch) && ch != '_') |
| ) |
| ) { |
| /* handle parameter expansions |
| * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02 |
| */ |
| if (first_char) |
| goto case_default; |
| switch (ch) { |
| case ':': /* null modifier */ |
| if (expansion == 0) { |
| debug_printf_parse(": null modifier\n"); |
| ++expansion; |
| break; |
| } |
| goto case_default; |
| case '#': /* remove prefix */ |
| case '%': /* remove suffix */ |
| if (expansion == 0) { |
| debug_printf_parse(": remove suffix/prefix\n"); |
| expansion = 2; |
| break; |
| } |
| goto case_default; |
| case '-': /* default value */ |
| case '=': /* assign default */ |
| case '+': /* alternative */ |
| case '?': /* error indicate */ |
| debug_printf_parse(": parameter expansion\n"); |
| expansion = 2; |
| break; |
| default: |
| case_default: |
| syntax_error_unterm_str("${name}"); |
| debug_printf_parse("handle_dollar return 1: unterminated ${name}\n"); |
| return 1; |
| } |
| } |
| char_ok: |
| debug_printf_parse(": '%c'\n", ch); |
| o_addchr(dest, ch | quote_mask); |
| quote_mask = 0; |
| first_char = false; |
| } /* while (1) */ |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| break; |
| } |
| #if ENABLE_SH_MATH_SUPPORT || ENABLE_HUSH_TICK |
| case '(': { |
| # if !BB_MMU |
| int pos; |
| # endif |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| # if ENABLE_SH_MATH_SUPPORT |
| if (i_peek(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; |
| # endif |
| add_till_closing_paren(dest, input, true); |
| # if !BB_MMU |
| if (as_string) { |
| o_addstr(as_string, dest->data + pos); |
| o_addchr(as_string, ')'); |
| o_addchr(as_string, ')'); |
| } |
| # endif |
| 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; |
| # endif |
| add_till_closing_paren(dest, input, false); |
| # if !BB_MMU |
| if (as_string) { |
| o_addstr(as_string, dest->data + pos); |
| o_addchr(as_string, ')'); |
| } |
| # endif |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| # endif |
| break; |
| } |
| #endif |
| case '_': |
| ch = i_getch(input); |
| nommu_addchr(as_string, ch); |
| ch = i_peek(input); |
| if (isalnum(ch)) { /* it's $_name or $_123 */ |
| ch = '_'; |
| goto make_var; |
| } |
| /* else: it's $_ */ |
| /* TODO: $_ and $-: */ |
| /* $_ 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 */ |
| /* $- Option flags set by set builtin or shell options (-i etc) */ |
| default: |
| o_addQchr(dest, '$'); |
| } |
| debug_printf_parse("handle_dollar return 0\n"); |
| return 0; |
| } |
| |
| #if BB_MMU |
| #define parse_stream_dquoted(as_string, dest, input, dquote_end) \ |
| parse_stream_dquoted(dest, input, dquote_end) |
| #endif |
| static int parse_stream_dquoted(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 */ |
| if (dest->o_assignment == NOT_ASSIGNMENT) |
| dest->o_escape ^= 1; |
| debug_printf_parse("parse_stream_dquoted return 0\n"); |
| return 0; |
| } |
| /* note: can't move it above ch == dquote_end check! */ |
| if (ch == EOF) { |
| syntax_error_unterm_ch('"'); |
| /*xfunc_die(); - redundant */ |
| } |
| next = '\0'; |
| if (ch != '\n') { |
| next = i_peek(input); |
| } |
| debug_printf_parse("\" ch=%c (%d) escape=%d\n", |
| ch, ch, dest->o_escape); |
| if (ch == '\\') { |
| if (next == EOF) { |
| syntax_error("\\<eof>"); |
| xfunc_die(); |
| } |
| /* bash: |
| * "The backslash retains its special meaning [in "..."] |
| * only when followed by one of the following characters: |
| * $, `, ", \, or <newline>. A double quote may be quoted |
| * within double quotes by preceding it with a backslash." |
| */ |
| if (strchr("$`\"\\\n", next) != NULL) { |
| ch = i_getch(input); |
| if (ch != '\n') { |
| o_addqchr(dest, ch); |
| nommu_addchr(as_string, ch); |
| } |
| } else { |
| o_addqchr(dest, '\\'); |
| nommu_addchr(as_string, '\\'); |
| } |
| goto again; |
| } |
| if (ch == '$') { |
| if (handle_dollar(as_string, dest, input) != 0) { |
| debug_printf_parse("parse_stream_dquoted return 1: " |
| "handle_dollar returned non-0\n"); |
| return 1; |
| } |
| goto again; |
| } |
| #if ENABLE_HUSH_TICK |
| if (ch == '`') { |
| //int pos = dest->length; |
| o_addchr(dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(dest, 0x80 | '`'); |
| add_till_backquote(dest, input); |
| 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 == '=' |
| && (dest->o_assignment == MAYBE_ASSIGNMENT |
| || dest->o_assignment == WORD_IS_KEYWORD) |
| && is_well_formed_var_name(dest->data, '=') |
| ) { |
| dest->o_assignment = DEFINITELY_ASSIGNMENT; |
| } |
| goto again; |
| } |
| |
| /* |
| * 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 is shell is not interactive, |
| * reset parsing machinery and start parsing anew, |
| * or return ERR_PTR. |
| */ |
| static struct pipe *parse_stream(char **pstring, |
| struct in_str *input, |
| int end_trigger) |
| { |
| struct parse_context ctx; |
| o_string dest = NULL_O_STRING; |
| int is_in_dquote; |
| int heredoc_cnt; |
| |
| /* Double-quote state is handled in the state variable is_in_dquote. |
| * A single-quote triggers a bypass of the main loop until its mate is |
| * found. When recursing, quote state is passed in via dest->o_escape. |
| */ |
| debug_printf_parse("parse_stream entered, end_trigger='%c'\n", |
| end_trigger ? end_trigger : 'X'); |
| debug_enter(); |
| |
| /* If very first arg is "" or '', dest.data may end up NULL. |
| * Preventing this: */ |
| o_addchr(&dest, '\0'); |
| dest.length = 0; |
| |
| G.ifs = get_local_var_value("IFS"); |
| if (G.ifs == NULL) |
| G.ifs = " \t\n"; |
| |
| reset: |
| #if ENABLE_HUSH_INTERACTIVE |
| input->promptmode = 0; /* PS1 */ |
| #endif |
| /* dest.o_assignment = MAYBE_ASSIGNMENT; - already is */ |
| initialize_context(&ctx); |
| is_in_dquote = 0; |
| heredoc_cnt = 0; |
| while (1) { |
| const char *is_ifs; |
| const char *is_special; |
| int ch; |
| int next; |
| int redir_fd; |
| redir_type redir_style; |
| |
| if (is_in_dquote) { |
| /* dest.o_quoted = 1; - already is (see below) */ |
| if (parse_stream_dquoted(&ctx.as_string, &dest, input, '"')) { |
| goto parse_error; |
| } |
| /* We reached closing '"' */ |
| is_in_dquote = 0; |
| } |
| ch = i_getch(input); |
| debug_printf_parse(": ch=%c (%d) escape=%d\n", |
| ch, ch, dest.o_escape); |
| if (ch == EOF) { |
| struct pipe *pi; |
| |
| if (heredoc_cnt) { |
| syntax_error_unterm_str("here document"); |
| goto parse_error; |
| } |
| /* end_trigger == '}' case errors out earlier, |
| * checking only ')' */ |
| if (end_trigger == ')') { |
| syntax_error_unterm_ch('('); /* exits */ |
| /* goto parse_error; */ |
| } |
| |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| o_free(&dest); |
| 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_string '%s'\n", ctx.as_string.data); |
| if (pstring) |
| *pstring = ctx.as_string.data; |
| else |
| o_free_unsafe(&ctx.as_string); |
| #endif |
| debug_leave(); |
| debug_printf_parse("parse_stream return %p\n", pi); |
| return pi; |
| } |
| nommu_addchr(&ctx.as_string, ch); |
| |
| next = '\0'; |
| if (ch != '\n') |
| next = i_peek(input); |
| |
| is_special = "{}<>;&|()#'" /* special outside of "str" */ |
| "\\$\"" IF_HUSH_TICK("`"); /* always special */ |
| /* Are { and } special here? */ |
| if (ctx.command->argv /* word [word]{... */ |
| || dest.length /* word{... */ |
| || dest.o_quoted /* ""{... */ |
| || (next != ';' && next != ')' && !strchr(G.ifs, next)) /* {word */ |
| ) { |
| /* They are not special, skip "{}" */ |
| is_special += 2; |
| } |
| is_special = strchr(is_special, ch); |
| is_ifs = strchr(G.ifs, ch); |
| |
| if (!is_special && !is_ifs) { /* ordinary char */ |
| ordinary_char: |
| o_addQchr(&dest, ch); |
| if ((dest.o_assignment == MAYBE_ASSIGNMENT |
| || dest.o_assignment == WORD_IS_KEYWORD) |
| && ch == '=' |
| && is_well_formed_var_name(dest.data, '=') |
| ) { |
| dest.o_assignment = DEFINITELY_ASSIGNMENT; |
| } |
| continue; |
| } |
| |
| if (is_ifs) { |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| if (ch == '\n') { |
| #if ENABLE_HUSH_CASE |
| /* "case ... in <newline> word) ..." - |
| * newlines are ignored (but ';' wouldn't be) */ |
| if (ctx.command->argv == NULL |
| && ctx.ctx_res_w == RES_MATCH |
| ) { |
| continue; |
| } |
| #endif |
| /* Treat newline as a command separator. */ |
| done_pipe(&ctx, PIPE_SEQ); |
| debug_printf_parse("heredoc_cnt:%d\n", heredoc_cnt); |
| if (heredoc_cnt) { |
| if (fetch_heredocs(heredoc_cnt, &ctx, input)) { |
| goto parse_error; |
| } |
| heredoc_cnt = 0; |
| } |
| dest.o_assignment = MAYBE_ASSIGNMENT; |
| ch = ';'; |
| /* note: if (is_ifs) 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 (!IS_NULL_CMD(ctx.command) /* cmd } */ |
| || dest.length != 0 /* word} */ |
| || dest.o_quoted /* ""} */ |
| ) { |
| goto ordinary_char; |
| } |
| if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */ |
| goto skip_end_trigger; |
| /* else: } does terminate a group */ |
| } |
| |
| if (end_trigger && end_trigger == ch |
| && (ch != ';' || heredoc_cnt == 0) |
| #if ENABLE_HUSH_CASE |
| && (ch != ')' |
| || ctx.ctx_res_w != RES_MATCH |
| || (!dest.o_quoted && strcmp(dest.data, "esac") == 0) |
| ) |
| #endif |
| ) { |
| if (heredoc_cnt) { |
| /* This is technically valid: |
| * { cat <<HERE; }; echo Ok |
| * heredoc |
| * heredoc |
| * HERE |
| * but we don't support this. |
| * We require heredoc to be in enclosing {}/(), |
| * if any. |
| */ |
| syntax_error_unterm_str("here document"); |
| goto parse_error; |
| } |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| done_pipe(&ctx, PIPE_SEQ); |
| dest.o_assignment = MAYBE_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(&dest); |
| #if !BB_MMU |
| debug_printf_parse("as_string '%s'\n", ctx.as_string.data); |
| if (pstring) |
| *pstring = ctx.as_string.data; |
| else |
| o_free_unsafe(&ctx.as_string); |
| #endif |
| debug_leave(); |
| debug_printf_parse("parse_stream return %p: " |
| "end_trigger char found\n", |
| ctx.list_head); |
| return ctx.list_head; |
| } |
| } |
| skip_end_trigger: |
| if (is_ifs) |
| 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(&dest); |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| 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; |
| } |
| #endif |
| if (parse_redirect(&ctx, redir_fd, redir_style, input)) |
| goto parse_error; |
| continue; /* back to top of while (1) */ |
| case '<': |
| redir_fd = redirect_opt_num(&dest); |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| redir_style = REDIRECT_INPUT; |
| if (next == '<') { |
| redir_style = REDIRECT_HEREDOC; |
| heredoc_cnt++; |
| debug_printf_parse("++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; |
| } |
| #endif |
| if (parse_redirect(&ctx, redir_fd, redir_style, input)) |
| goto parse_error; |
| continue; /* back to top of while (1) */ |
| } |
| |
| if (dest.o_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 */ |
| dest.o_assignment = NOT_ASSIGNMENT; |
| } |
| |
| /* Note: nommu_addchr(&ctx.as_string, ch) is already done */ |
| |
| switch (ch) { |
| case '#': |
| if (dest.length == 0) { |
| while (1) { |
| ch = i_peek(input); |
| if (ch == EOF || ch == '\n') |
| break; |
| i_getch(input); |
| /* note: we do not add it to &ctx.as_string */ |
| } |
| nommu_addchr(&ctx.as_string, '\n'); |
| } else { |
| o_addQchr(&dest, ch); |
| } |
| break; |
| case '\\': |
| if (next == EOF) { |
| syntax_error("\\<eof>"); |
| xfunc_die(); |
| } |
| ch = i_getch(input); |
| if (ch != '\n') { |
| o_addchr(&dest, '\\'); |
| /*nommu_addchr(&ctx.as_string, '\\'); - already done */ |
| o_addchr(&dest, ch); |
| nommu_addchr(&ctx.as_string, ch); |
| /* Example: echo Hello \2>file |
| * we need to know that word 2 is quoted */ |
| dest.o_quoted = 1; |
| } |
| #if !BB_MMU |
| else { |
| /* It's "\<newline>". Remove trailing '\' from ctx.as_string */ |
| ctx.as_string.data[--ctx.as_string.length] = '\0'; |
| } |
| #endif |
| break; |
| case '$': |
| if (handle_dollar(&ctx.as_string, &dest, input) != 0) { |
| debug_printf_parse("parse_stream parse error: " |
| "handle_dollar returned non-0\n"); |
| goto parse_error; |
| } |
| break; |
| case '\'': |
| dest.o_quoted = 1; |
| while (1) { |
| ch = i_getch(input); |
| if (ch == EOF) { |
| syntax_error_unterm_ch('\''); |
| /*xfunc_die(); - redundant */ |
| } |
| nommu_addchr(&ctx.as_string, ch); |
| if (ch == '\'') |
| break; |
| o_addqchr(&dest, ch); |
| } |
| break; |
| case '"': |
| dest.o_quoted = 1; |
| is_in_dquote ^= 1; /* invert */ |
| if (dest.o_assignment == NOT_ASSIGNMENT) |
| dest.o_escape ^= 1; |
| break; |
| #if ENABLE_HUSH_TICK |
| case '`': { |
| #if !BB_MMU |
| int pos; |
| #endif |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| o_addchr(&dest, '`'); |
| #if !BB_MMU |
| pos = dest.length; |
| #endif |
| add_till_backquote(&dest, input); |
| #if !BB_MMU |
| o_addstr(&ctx.as_string, dest.data + pos); |
| o_addchr(&ctx.as_string, '`'); |
| #endif |
| o_addchr(&dest, SPECIAL_VAR_SYMBOL); |
| //debug_printf_subst("SUBST RES3 '%s'\n", dest.data + pos); |
| break; |
| } |
| #endif |
| case ';': |
| #if ENABLE_HUSH_CASE |
| case_semi: |
| #endif |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| done_pipe(&ctx, PIPE_SEQ); |
| #if ENABLE_HUSH_CASE |
| /* Eat multiple semicolons, detect |
| * whether it means something special */ |
| while (1) { |
| ch = i_peek(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 */ |
| dest.o_assignment = MAYBE_ASSIGNMENT; |
| break; |
| case '&': |
| if (done_word(&dest, &ctx)) { |
| goto parse_error; |
| } |
| 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(&dest, &ctx)) { |
| goto parse_error; |
| } |
| #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); |
| #if !BB_MMU |
| o_reset_to_empty_unquoted(&ctx.as_string); |
| #endif |
| } |
| 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|(... */ |
| && dest.length == 0 /* not word(... */ |
| && dest.o_quoted == 0 /* not ""(... */ |
| ) { |
| continue; |
| } |
| #endif |
| case '{': |
| if (parse_group(&dest, &ctx, input, ch) != 0) { |
| goto parse_error; |
| } |
| 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). */ |
| syntax_error_unexpected_ch(ch); |
| goto parse_error; |
| default: |
| if (HUSH_DEBUG) |
| bb_error_msg_and_die("BUG: unexpected %c\n", ch); |
| } |
| } /* while (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_unsafe(&pctx->as_string); |
| #endif |
| IF_HAS_KEYWORDS(p2 = pctx->stack;) |
| if (pctx != &ctx) { |
| free(pctx); |
| } |
| IF_HAS_KEYWORDS(pctx = p2;) |
| } while (HAS_KEYWORDS && pctx); |
| /* Free text, clear all dest fields */ |
| o_free(&dest); |
| /* If we are not in top-level parse, we return, |
| * our caller will propagate error. |
| */ |
| if (end_trigger != ';') { |
| #if !BB_MMU |
| if (pstring) |
| *pstring = NULL; |
| #endif |
| debug_leave(); |
| return ERR_PTR; |
| } |
| /* Discard cached input, force prompt */ |
| input->p = NULL; |
| IF_HUSH_INTERACTIVE(input->promptme = 1;) |
| goto reset; |
| } |
| } |
| |
| /* 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; |
| |
| pipe_list = parse_stream(NULL, inp, end_trigger); |
| if (!pipe_list) { /* EOF */ |
| if (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; |
| } |
| } |
| |
| static void parse_and_run_string(const char *s) |
| { |
| struct in_str input; |
| setup_string_in_str(&input, s); |
| parse_and_run_stream(&input, '\0'); |
| } |
| |
| static void parse_and_run_file(FILE *f) |
| { |
| struct in_str input; |
| setup_file_in_str(&input, f); |
| parse_and_run_stream(&input, ';'); |
| } |
| |
| /* Called a few times only (or even once if "sh -c") */ |
| static void init_sigmasks(void) |
| { |
| unsigned sig; |
| unsigned mask; |
| sigset_t old_blocked_set; |
| |
| if (!G.inherited_set_is_saved) { |
| sigprocmask(SIG_SETMASK, NULL, &G.blocked_set); |
| G.inherited_set = G.blocked_set; |
| } |
| old_blocked_set = G.blocked_set; |
| |
| mask = (1 << SIGQUIT); |
| if (G_interactive_fd) { |
| mask = (1 << SIGQUIT) | SPECIAL_INTERACTIVE_SIGS; |
| if (G_saved_tty_pgrp) /* we have ctty, job control sigs work */ |
| mask |= SPECIAL_JOB_SIGS; |
| } |
| G.non_DFL_mask = mask; |
| |
| sig = 0; |
| while (mask) { |
| if (mask & 1) |
| sigaddset(&G.blocked_set, sig); |
| mask >>= 1; |
| sig++; |
| } |
| sigdelset(&G.blocked_set, SIGCHLD); |
| |
| if (memcmp(&old_blocked_set, &G.blocked_set, sizeof(old_blocked_set)) != 0) |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| |
| /* POSIX allows shell to re-enable SIGCHLD |
| * even if it was SIG_IGN on entry */ |
| #if ENABLE_HUSH_FAST |
| G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */ |
| if (!G.inherited_set_is_saved) |
| signal(SIGCHLD, SIGCHLD_handler); |
| #else |
| if (!G.inherited_set_is_saved) |
| signal(SIGCHLD, SIG_DFL); |
| #endif |
| |
| G.inherited_set_is_saved = 1; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* helper */ |
| static void maybe_set_to_sigexit(int sig) |
| { |
| void (*handler)(int); |
| /* non_DFL_mask'ed signals are, well, masked, |
| * no need to set handler for them. |
| */ |
| if (!((G.non_DFL_mask >> sig) & 1)) { |
| handler = signal(sig, sigexit); |
| if (handler == SIG_IGN) /* oops... restore back to IGN! */ |
| signal(sig, handler); |
| } |
| } |
| /* Set handlers to restore tty pgrp and exit */ |
| static void set_fatal_handlers(void) |
| { |
| /* We _must_ restore tty pgrp on fatal signals */ |
| if (HUSH_DEBUG) { |
| maybe_set_to_sigexit(SIGILL ); |
| maybe_set_to_sigexit(SIGFPE ); |
| maybe_set_to_sigexit(SIGBUS ); |
| maybe_set_to_sigexit(SIGSEGV); |
| maybe_set_to_sigexit(SIGTRAP); |
| } /* else: hush is perfect. what SEGV? */ |
| maybe_set_to_sigexit(SIGABRT); |
| /* bash 3.2 seems to handle these just like 'fatal' ones */ |
| maybe_set_to_sigexit(SIGPIPE); |
| maybe_set_to_sigexit(SIGALRM); |
| /* if we are interactive, SIGHUP, SIGTERM and SIGINT are masked. |
| * if we aren't interactive... but in this case |
| * we never want to restore pgrp on exit, and this fn is not called */ |
| /*maybe_set_to_sigexit(SIGHUP );*/ |
| /*maybe_set_to_sigexit(SIGTERM);*/ |
| /*maybe_set_to_sigexit(SIGINT );*/ |
| } |
| #endif |
| |
| static int set_mode(const char cstate, const char mode) |
| { |
| int state = (cstate == '-' ? 1 : 0); |
| switch (mode) { |
| case 'n': G.fake_mode = state; break; |
| case 'x': /*G.debug_mode = state;*/ break; |
| default: return EXIT_FAILURE; |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int hush_main(int argc, char **argv) |
| { |
| static const struct variable const_shell_ver = { |
| .next = NULL, |
| .varstr = (char*)hush_version_str, |
| .max_len = 1, /* 0 can provoke free(name) */ |
| .flg_export = 1, |
| .flg_read_only = 1, |
| }; |
| int opt; |
| unsigned builtin_argc; |
| char **e; |
| struct variable *cur_var; |
| |
| INIT_G(); |
| if (EXIT_SUCCESS) /* if EXIT_SUCCESS == 0, is already done */ |
| G.last_exitcode = EXIT_SUCCESS; |
| #if !BB_MMU |
| G.argv0_for_re_execing = argv[0]; |
| #endif |
| /* Deal with HUSH_VERSION */ |
| G.shell_ver = const_shell_ver; /* copying struct here */ |
| G.top_var = &G.shell_ver; |
| debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION"); |
| unsetenv("HUSH_VERSION"); /* in case it exists in initial env */ |
| /* Initialize our shell local variables with the values |
| * currently living in the environment */ |
| 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++; |
| } |
| /* reinstate HUSH_VERSION */ |
| debug_printf_env("putenv '%s'\n", hush_version_str); |
| putenv((char *)hush_version_str); |
| |
| /* Export PWD */ |
| set_pwd_var(/*exp:*/ 1); |
| /* 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 |
| * HOSTNAME=<xxxxxxxxxx> |
| * 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 |
| * IFS=$' \t\n' |
| * PS1='\s-\v\$ ' |
| * PS2='> ' |
| * PS4='+ ' |
| */ |
| |
| #if ENABLE_FEATURE_EDITING |
| G.line_input_state = new_line_input_t(FOR_SHELL); |
| #endif |
| G.global_argc = argc; |
| G.global_argv = argv; |
| /* Initialize some more globals to non-zero values */ |
| cmdedit_update_prompt(); |
| |
| if (setjmp(die_jmp)) { |
| /* xfunc has failed! die die die */ |
| /* no EXIT traps, this is an escape hatch! */ |
| G.exiting = 1; |
| hush_exit(xfunc_error_retval); |
| } |
| |
| /* Shell is non-interactive at first. We need to call |
| * init_sigmasks() 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 init_sigmasks() |
| * in order to intercept (more) signals. |
| */ |
| |
| /* Parse options */ |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */ |
| builtin_argc = 0; |
| while (1) { |
| opt = getopt(argc, argv, "+c:xins" |
| #if !BB_MMU |
| "<:$:R:V:" |
| # if ENABLE_HUSH_FUNCTIONS |
| "F:" |
| # endif |
| #endif |
| ); |
| if (opt <= 0) |
| break; |
| switch (opt) { |
| case '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: this form never happens: |
| * sh ... -c 'builtin' [BARGV...] "" |
| */ |
| if (!G.root_pid) { |
| G.root_pid = getpid(); |
| G.root_ppid = getppid(); |
| } |
| G.global_argv = argv + optind; |
| G.global_argc = argc - optind; |
| if (builtin_argc) { |
| /* -c 'builtin' [BARGV...] "" ARG0 [ARG1...] */ |
| const struct built_in_command *x; |
| |
| init_sigmasks(); |
| x = find_builtin(optarg); |
| if (x) { /* paranoia */ |
| G.global_argc -= builtin_argc; /* skip [BARGV...] "" */ |
| G.global_argv += builtin_argc; |
| G.global_argv[-1] = NULL; /* replace "" */ |
| G.last_exitcode = x->function(argv + optind - 1); |
| } |
| goto final_return; |
| } |
| if (!G.global_argv[0]) { |
| /* -c 'script' (no params): prevent empty $0 */ |
| G.global_argv--; /* points to argv[i] of 'script' */ |
| G.global_argv[0] = argv[0]; |
| G.global_argc--; |
| } /* else -c 'script' ARG0 [ARG1...]: $0 is ARG0 */ |
| init_sigmasks(); |
| parse_and_run_string(optarg); |
| goto final_return; |
| case 'i': |
| /* Well, we cannot just declare interactiveness, |
| * we have to have some stuff (ctty, etc) */ |
| /* G_interactive_fd++; */ |
| break; |
| case 's': |
| /* "-s" means "read from stdin", but this is how we always |
| * operate, so simply do nothing here. */ |
| break; |
| #if !BB_MMU |
| case '<': /* "big heredoc" support */ |
| full_write(STDOUT_FILENO, optarg, strlen(optarg)); |
| _exit(0); |
| case '$': { |
| 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) { |
| int sig; |
| init_sigmasks(); |
| 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(""); */ |
| sigaddset(&G.blocked_set, sig); |
| } |
| } |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| } |
| # if ENABLE_HUSH_LOOPS |
| optarg++; |
| G.depth_of_loop = bb_strtou(optarg, &optarg, 16); |
| # endif |
| break; |
| } |
| case 'R': |
| case 'V': |
| set_local_var(xstrdup(optarg), /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ opt == 'R'); |
| 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 'n': |
| case 'x': |
| if (!set_mode('-', opt)) |
| break; |
| default: |
| #ifndef BB_VER |
| fprintf(stderr, "Usage: sh [FILE]...\n" |
| " or: sh -c command [args]...\n\n"); |
| exit(EXIT_FAILURE); |
| #else |
| bb_show_usage(); |
| #endif |
| } |
| } /* option parsing loop */ |
| |
| if (!G.root_pid) { |
| G.root_pid = getpid(); |
| G.root_ppid = getppid(); |
| } |
| |
| /* If we are login shell... */ |
| if (argv[0] && argv[0][0] == '-') { |
| FILE *input; |
| debug_printf("sourcing /etc/profile\n"); |
| input = fopen_for_read("/etc/profile"); |
| if (input != NULL) { |
| close_on_exec_on(fileno(input)); |
| init_sigmasks(); |
| parse_and_run_file(input); |
| fclose(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 (argv[optind]) { |
| FILE *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. |
| */ |
| debug_printf("running script '%s'\n", argv[optind]); |
| G.global_argv = argv + optind; |
| G.global_argc = argc - optind; |
| input = xfopen_for_read(argv[optind]); |
| close_on_exec_on(fileno(input)); |
| init_sigmasks(); |
| parse_and_run_file(input); |
| #if ENABLE_FEATURE_CLEAN_UP |
| fclose(input); |
| #endif |
| goto final_return; |
| } |
| |
| /* Up to here, shell was non-interactive. Now it may become one. |
| * NB: don't forget to (re)run init_sigmasks() 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 = fcntl(STDIN_FILENO, F_DUPFD, 255); |
| 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; |
| } |
| } |
| // TODO: track & disallow any attempts of user |
| // to (inadvertently) close/redirect G_interactive_fd |
| } |
| 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); |
| } |
| } |
| |
| /* Block some signals */ |
| init_sigmasks(); |
| |
| if (G_saved_tty_pgrp) { |
| /* Set other signals to restore saved_tty_pgrp */ |
| set_fatal_handlers(); |
| /* 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, getpid()); |
| } |
| /* -1 is special - makes xfuncs longjmp, not exit |
| * (we reset die_sleep = 0 whereever we [v]fork) */ |
| enable_restore_tty_pgrp_on_exit(); /* sets die_sleep = -1 */ |
| } else { |
| init_sigmasks(); |
| } |
| #elif ENABLE_HUSH_INTERACTIVE |
| /* No job control compiled in, only prompt/line editing */ |
| if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) { |
| G_interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255); |
| 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; |
| } |
| } |
| if (G_interactive_fd) { |
| close_on_exec_on(G_interactive_fd); |
| } |
| init_sigmasks(); |
| #else |
| /* We have interactiveness code disabled */ |
| init_sigmasks(); |
| #endif |
| /* bash: |
| * if interactive but not a login shell, sources ~/.bashrc |
| * (--norc turns this off, --rcfile <file> overrides) |
| */ |
| |
| if (!ENABLE_FEATURE_SH_EXTRA_QUIET && G_interactive_fd) { |
| /* 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(stdin); |
| |
| final_return: |
| #if ENABLE_FEATURE_CLEAN_UP |
| if (G.cwd != bb_msg_unknown) |
| free((char*)G.cwd); |
| cur_var = G.top_var->next; |
| 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 |
| hush_exit(G.last_exitcode); |
| } |
| |
| |
| #if ENABLE_LASH |
| int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int lash_main(int argc, char **argv) |
| { |
| bb_error_msg("lash is deprecated, please use hush instead"); |
| return hush_main(argc, argv); |
| } |
| #endif |
| |
| #if ENABLE_MSH |
| int msh_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int msh_main(int argc, char **argv) |
| { |
| //bb_error_msg("msh is deprecated, please use hush instead"); |
| return hush_main(argc, argv); |
| } |
| #endif |
| |
| |
| /* |
| * Built-ins |
| */ |
| static int FAST_FUNC builtin_true(char **argv UNUSED_PARAM) |
| { |
| return 0; |
| } |
| |
| static int run_applet_main(char **argv, int (*applet_main_func)(int argc, char **argv)) |
| { |
| int argc = 0; |
| while (*argv) { |
| argc++; |
| argv++; |
| } |
| return applet_main_func(argc, argv - argc); |
| } |
| |
| static int FAST_FUNC builtin_test(char **argv) |
| { |
| return run_applet_main(argv, test_main); |
| } |
| |
| static int FAST_FUNC builtin_echo(char **argv) |
| { |
| return run_applet_main(argv, echo_main); |
| } |
| |
| #if ENABLE_PRINTF |
| static int FAST_FUNC builtin_printf(char **argv) |
| { |
| return run_applet_main(argv, printf_main); |
| } |
| #endif |
| |
| static int FAST_FUNC builtin_eval(char **argv) |
| { |
| int rcode = EXIT_SUCCESS; |
| |
| if (*++argv) { |
| char *str = expand_strvec_to_string(argv); |
| /* bash: |
| * eval "echo Hi; done" ("done" is syntax error): |
| * "echo Hi" will not execute too. |
| */ |
| parse_and_run_string(str); |
| free(str); |
| rcode = G.last_exitcode; |
| } |
| return rcode; |
| } |
| |
| static int FAST_FUNC builtin_cd(char **argv) |
| { |
| const char *newdir = argv[1]; |
| 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(/*exp:*/ 0); |
| return EXIT_SUCCESS; |
| } |
| |
| static int FAST_FUNC builtin_exec(char **argv) |
| { |
| if (*++argv == 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); |
| |
| /* TODO: if exec fails, bash does NOT exit! We do. |
| * We'll need to undo sigprocmask (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) |
| * |
| * we can use G.exiting = -1 as indicator "last cmd was exit" |
| */ |
| |
| /* note: EXIT trap is run by hush_exit */ |
| if (*++argv == NULL) |
| 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) & 0xff); |
| } |
| |
| 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); |
| } |
| |
| #if !ENABLE_HUSH_LOCAL |
| #define helper_export_local(argv, exp, lvl) \ |
| helper_export_local(argv, exp) |
| #endif |
| static void helper_export_local(char **argv, int exp, int lvl) |
| { |
| do { |
| char *name = *argv; |
| |
| /* So far we do not check that name is valid (TODO?) */ |
| |
| if (strchr(name, '=') == NULL) { |
| struct variable *var; |
| |
| var = get_local_var(name); |
| if (exp == -1) { /* unexporting? */ |
| /* 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 (exp == 1) { /* exporting? */ |
| /* export NAME (without =VALUE) */ |
| if (var) { |
| var->flg_export = 1; |
| debug_printf_env("%s: putenv '%s'\n", __func__, var->varstr); |
| putenv(var->varstr); |
| continue; |
| } |
| } |
| /* 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 "". */ |
| name = xasprintf("%s=", name); |
| } else { |
| /* (Un)exporting/making local NAME=VALUE */ |
| name = xstrdup(name); |
| } |
| set_local_var(name, /*exp:*/ exp, /*lvl:*/ lvl, /*ro:*/ 0); |
| } while (*++argv); |
| } |
| |
| 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; |
| } |
| |
| helper_export_local(argv, (opt_unexport ? -1 : 1), 0); |
| |
| return EXIT_SUCCESS; |
| } |
| |
| #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 */ |
| } |
| helper_export_local(argv, 0, G.func_nest_level); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| 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) { |
| sig = get_signum(*argv++); |
| if (sig < 0 || sig >= NSIG) { |
| ret = EXIT_FAILURE; |
| /* Mimic bash message exactly */ |
| bb_perror_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) { |
| sigaddset(&G.blocked_set, sig); |
| } else { |
| /* There was a trap handler, we are removing it |
| * (if sig has non-DFL handling, |
| * we don't need to do anything) */ |
| if (sig < 32 && (G.non_DFL_mask & (1 << sig))) |
| continue; |
| sigdelset(&G.blocked_set, sig); |
| } |
| } |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| return ret; |
| } |
| |
| if (!argv[1]) { /* no second arg */ |
| bb_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; |
| } |
| |
| /* 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; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* built-in 'fg' and 'bg' handler */ |
| static int FAST_FUNC builtin_fg_bg(char **argv) |
| { |
| int i, jobnum; |
| 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; |
| } |
| if (sscanf(argv[1], "%%%d", &jobnum) != 1) { |
| bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]); |
| return EXIT_FAILURE; |
| } |
| for (pi = G.job_list; pi; pi = pi->next) { |
| if (pi->jobid == jobnum) { |
| goto found; |
| } |
| } |
| bb_error_msg("%s: %d: no such job", argv[0], jobnum); |
| 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->cmds[i].is_stopped = 0; |
| } |
| pi->stopped_cmds = 0; |
| |
| i = kill(- pi->pgrp, SIGCONT); |
| if (i < 0) { |
| if (errno == ESRCH) { |
| delete_finished_bg_job(pi); |
| return EXIT_SUCCESS; |
| } |
| bb_perror_msg("kill (SIGCONT)"); |
| } |
| |
| if (argv[0][0] == 'f') { |
| remove_bg_job(pi); |
| return checkjobs_and_fg_shell(pi); |
| } |
| return EXIT_SUCCESS; |
| } |
| #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->descr) |
| printf("%s\t%s\n", x->cmd, x->descr); |
| } |
| bb_putchar('\n'); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_JOB |
| static int FAST_FUNC builtin_jobs(char **argv UNUSED_PARAM) |
| { |
| struct pipe *job; |
| const char *status_string; |
| |
| 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); |
| } |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if HUSH_DEBUG |
| 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 (!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 |
| |
| static int FAST_FUNC builtin_pwd(char **argv UNUSED_PARAM) |
| { |
| puts(get_cwd(0)); |
| return EXIT_SUCCESS; |
| } |
| |
| static int FAST_FUNC builtin_read(char **argv) |
| { |
| char *string; |
| const char *name = "REPLY"; |
| |
| if (argv[1]) { |
| name = argv[1]; |
| /* bash (3.2.33(1)) bug: "read 0abcd" will execute, |
| * and _after_ that_ it will complain */ |
| if (!is_well_formed_var_name(name, '\0')) { |
| /* Mimic bash message */ |
| bb_error_msg("read: '%s': not a valid identifier", name); |
| return 1; |
| } |
| } |
| |
| //TODO: bash unbackslashes input, splits words and puts them in argv[i] |
| |
| string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name), NULL); |
| return set_local_var(string, /*exp:*/ 0, /*lvl:*/ 0, /*ro:*/ 0); |
| } |
| |
| /* 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, "--")) { |
| ++argv; |
| goto set_argv; |
| } |
| if (arg[0] != '+' && arg[0] != '-') |
| break; |
| for (n = 1; arg[n]; ++n) |
| if (set_mode(arg[0], arg[n])) |
| goto error; |
| } 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); |
| |
| n = 1; |
| while (*++pp) |
| n++; |
| G.global_argc = n; |
| |
| return EXIT_SUCCESS; |
| |
| /* Nothing known, so abort */ |
| error: |
| bb_error_msg("set: %s: invalid option", arg); |
| return EXIT_FAILURE; |
| } |
| |
| static int FAST_FUNC builtin_shift(char **argv) |
| { |
| int n = 1; |
| if (argv[1]) { |
| n = atoi(argv[1]); |
| } |
| 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; |
| } |
| |
| static int FAST_FUNC builtin_source(char **argv) |
| { |
| char *arg_path; |
| FILE *input; |
| save_arg_t sv; |
| #if ENABLE_HUSH_FUNCTIONS |
| smallint sv_flg; |
| #endif |
| |
| if (*++argv == NULL) |
| return EXIT_FAILURE; |
| |
| if (strchr(*argv, '/') == NULL && (arg_path = find_in_path(*argv)) != NULL) { |
| input = fopen_for_read(arg_path); |
| free(arg_path); |
| } else |
| input = fopen_or_warn(*argv, "r"); |
| if (!input) { |
| /* bb_perror_msg("%s", *argv); - done by fopen_or_warn */ |
| return EXIT_FAILURE; |
| } |
| close_on_exec_on(fileno(input)); |
| |
| #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 |
| save_and_replace_G_args(&sv, argv); |
| |
| parse_and_run_file(input); |
| fclose(input); |
| |
| restore_G_args(&sv, argv); |
| #if ENABLE_HUSH_FUNCTIONS |
| G.flag_return_in_progress = sv_flg; |
| #endif |
| |
| return G.last_exitcode; |
| } |
| |
| static int FAST_FUNC builtin_umask(char **argv) |
| { |
| int rc; |
| mode_t mask; |
| |
| mask = umask(0); |
| if (argv[1]) { |
| mode_t old_mask = mask; |
| |
| mask ^= 0777; |
| rc = bb_parse_mode(argv[1], &mask); |
| mask ^= 0777; |
| if (rc == 0) { |
| mask = old_mask; |
| /* bash messages: |
| * bash: umask: 'q': invalid symbolic mode operator |
| * bash: umask: 999: octal number out of range |
| */ |
| bb_error_msg("%s: '%s' invalid mode", argv[0], argv[1]); |
| } |
| } else { |
| rc = 1; |
| /* Mimic bash */ |
| printf("%04o\n", (unsigned) mask); |
| /* fall through and restore mask which we set to 0 */ |
| } |
| umask(mask); |
| |
| return !rc; /* rc != 0 - success */ |
| } |
| |
| /* 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_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; |
| } |
| |
| /* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */ |
| static int FAST_FUNC builtin_wait(char **argv) |
| { |
| int ret = EXIT_SUCCESS; |
| int status, sig; |
| |
| if (*++argv == 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 |
| * $ |
| */ |
| sigaddset(&G.blocked_set, SIGCHLD); |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| while (1) { |
| checkjobs(NULL); |
| if (errno == ECHILD) |
| break; |
| /* Wait for SIGCHLD or any other signal of interest */ |
| /* sigtimedwait with infinite timeout: */ |
| sig = sigwaitinfo(&G.blocked_set, NULL); |
| if (sig > 0) { |
| sig = check_and_run_traps(sig); |
| if (sig && sig != SIGCHLD) { /* see note 2 */ |
| ret = 128 + sig; |
| break; |
| } |
| } |
| } |
| sigdelset(&G.blocked_set, SIGCHLD); |
| sigprocmask(SIG_SETMASK, &G.blocked_set, NULL); |
| return ret; |
| } |
| |
| /* This is probably buggy wrt interruptible-ness */ |
| while (*argv) { |
| pid_t pid = bb_strtou(*argv, NULL, 10); |
| if (errno) { |
| /* mimic bash message */ |
| bb_error_msg("wait: '%s': not a pid or valid job spec", *argv); |
| return EXIT_FAILURE; |
| } |
| if (waitpid(pid, &status, 0) == pid) { |
| if (WIFSIGNALED(status)) |
| ret = 128 + WTERMSIG(status); |
| else if (WIFEXITED(status)) |
| ret = WEXITSTATUS(status); |
| else /* wtf? */ |
| ret = EXIT_FAILURE; |
| } else { |
| bb_perror_msg("wait %s", *argv); |
| ret = 127; |
| } |
| argv++; |
| } |
| |
| return ret; |
| } |
| |
| #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]); |
| return EXIT_SUCCESS; /* bash compat */ |
| } |
| G.flag_break_continue++; /* BC_BREAK = 1 */ |
| |
| 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); |
| return rc; |
| } |
| #endif |