| /* mini man implementation for busybox |
| * Copyright (C) 2008 Denys Vlasenko <vda.linux@googlemail.com> |
| * Licensed under GPLv2, see file LICENSE in this source tree. |
| */ |
| //config:config MAN |
| //config: bool "man" |
| //config: default y |
| //config: help |
| //config: Format and display manual pages. |
| |
| //applet:IF_MAN(APPLET(man, BB_DIR_USR_BIN, BB_SUID_DROP)) |
| |
| //kbuild:lib-$(CONFIG_MAN) += man.o |
| |
| //usage:#define man_trivial_usage |
| //usage: "[-aw] [MANPAGE]..." |
| //usage:#define man_full_usage "\n\n" |
| //usage: "Format and display manual page\n" |
| //usage: "\n -a Display all pages" |
| //usage: "\n -w Show page locations" |
| //usage: "\n" |
| //usage: "\n$COLUMNS overrides output width" |
| |
| #include "libbb.h" |
| #include "common_bufsiz.h" |
| |
| enum { |
| OPT_a = 1, /* all */ |
| OPT_w = 2, /* print path */ |
| }; |
| |
| /* This is what I see on my desktop system being executed: |
| ( |
| echo ".ll 12.4i" |
| echo ".nr LL 12.4i" |
| echo ".pl 1100i" |
| gunzip -c '/usr/man/man1/bzip2.1.gz' |
| echo ".\\\"" |
| echo ".pl \n(nlu+10" |
| ) | gtbl | nroff -Tlatin1 -mandoc | less |
| |
| Some systems use -Tascii. |
| |
| On another system I see this: |
| |
| ... | tbl | nroff -mandoc -rLL=<NNN>n -rLT=<NNN>n -Tutf8 | less |
| |
| where <NNN> is screen width minus 5. |
| Replacing "DEFINE nroff nroff -mandoc" in /etc/man_db.conf |
| changes "nroff -mandoc" part; -rLL=<NNN>n, -rLT=<NNN>n and -Tutf8 parts are |
| appended to the user-specified command. |
| |
| Redirecting to a pipe or file sets GROFF_NO_SGR=1 to prevent color escapes, |
| and uses "col -b -p -x" instead of pager, this filters out backspace |
| and underscore tricks. |
| */ |
| |
| struct globals { |
| const char *col; |
| const char *tbl; |
| const char *nroff; |
| const char *pager; |
| } FIX_ALIASING; |
| #define G (*(struct globals*)bb_common_bufsiz1) |
| #define INIT_G() do { \ |
| setup_common_bufsiz(); \ |
| G.col = "col"; \ |
| G.tbl = "tbl"; \ |
| /* Removed -Tlatin1. Assuming system nroff has suitable default */ \ |
| G.nroff = "nroff -mandoc"; \ |
| G.pager = ENABLE_LESS ? "less" : "more"; \ |
| } while (0) |
| |
| static int show_manpage(char *man_filename, int man, int level); |
| |
| static int run_pipe(char *man_filename, int man, int level) |
| { |
| char *cmd; |
| |
| /* Prevent man page link loops */ |
| if (level > 10) |
| return 0; |
| |
| if (access(man_filename, R_OK) != 0) |
| return 0; |
| |
| if (option_mask32 & OPT_w) { |
| puts(man_filename); |
| return 1; |
| } |
| |
| if (man) { /* man page, not cat page */ |
| /* Is this a link to another manpage? */ |
| /* The link has the following on the first line: */ |
| /* ".so another_man_page" */ |
| |
| struct stat sb; |
| char *line; |
| char *linkname, *p; |
| |
| /* On my system: |
| * man1/genhostid.1.gz: 203 bytes - smallest real manpage |
| * man2/path_resolution.2.gz: 114 bytes - largest link |
| */ |
| xstat(man_filename, &sb); |
| if (sb.st_size > 300) /* err on the safe side */ |
| goto ordinary_manpage; |
| |
| line = xmalloc_open_zipped_read_close(man_filename, NULL); |
| if (!line || !is_prefixed_with(line, ".so ")) { |
| free(line); |
| goto ordinary_manpage; |
| } |
| /* Example: man2/path_resolution.2.gz contains |
| * ".so man7/path_resolution.7\n<junk>" |
| */ |
| *strchrnul(line, '\n') = '\0'; |
| linkname = skip_whitespace(&line[4]); |
| |
| /* If link has no slashes, we just replace man page name. |
| * If link has slashes (however many), we go back *once*. |
| * ".so zzz/ggg/page.3" does NOT go back two levels. */ |
| p = strrchr(man_filename, '/'); |
| if (!p) |
| goto ordinary_manpage; |
| *p = '\0'; |
| if (strchr(linkname, '/')) { |
| p = strrchr(man_filename, '/'); |
| if (!p) |
| goto ordinary_manpage; |
| *p = '\0'; |
| } |
| |
| /* Links do not have .gz extensions, even if manpage |
| * is compressed */ |
| man_filename = xasprintf("%s/%s", man_filename, linkname); |
| free(line); |
| /* Note: we leak "new" man_filename string as well... */ |
| if (show_manpage(man_filename, man, level + 1)) |
| return 1; |
| /* else: show the link, it's better than nothing */ |
| } |
| |
| ordinary_manpage: |
| close(STDIN_FILENO); |
| open_zipped(man_filename, /*fail_if_not_compressed:*/ 0); /* guaranteed to use fd 0 (STDIN_FILENO) */ |
| if (man) { |
| int w = get_terminal_width(-1); |
| if (w > 10) |
| w -= 2; |
| /* "2>&1" is added so that nroff errors are shown in pager too. |
| * Otherwise it may show just empty screen. |
| */ |
| cmd = xasprintf("%s | %s -rLL=%un -rLT=%un 2>&1 | %s", |
| G.tbl, G.nroff, w, w, |
| G.pager); |
| } else { |
| cmd = xstrdup(G.pager); |
| } |
| system(cmd); |
| free(cmd); |
| return 1; |
| } |
| |
| /* man_filename is of the form "/dir/dir/dir/name.s" */ |
| static int show_manpage(char *man_filename, int man, int level) |
| { |
| #if SEAMLESS_COMPRESSION |
| /* We leak this allocation... */ |
| char *filename_with_zext = xasprintf("%s.lzma", man_filename); |
| char *ext = strrchr(filename_with_zext, '.') + 1; |
| #endif |
| |
| #if ENABLE_FEATURE_SEAMLESS_LZMA |
| if (run_pipe(filename_with_zext, man, level)) |
| return 1; |
| #endif |
| #if ENABLE_FEATURE_SEAMLESS_XZ |
| strcpy(ext, "xz"); |
| if (run_pipe(filename_with_zext, man, level)) |
| return 1; |
| #endif |
| #if ENABLE_FEATURE_SEAMLESS_BZ2 |
| strcpy(ext, "bz2"); |
| if (run_pipe(filename_with_zext, man, level)) |
| return 1; |
| #endif |
| #if ENABLE_FEATURE_SEAMLESS_GZ |
| strcpy(ext, "gz"); |
| if (run_pipe(filename_with_zext, man, level)) |
| return 1; |
| #endif |
| |
| return run_pipe(man_filename, man, level); |
| } |
| |
| static char **add_MANPATH(char **man_path_list, int *count_mp, char *path) |
| { |
| if (path) while (*path) { |
| char *next_path; |
| char **path_element; |
| |
| next_path = strchr(path, ':'); |
| if (next_path) { |
| if (next_path == path) /* "::"? */ |
| goto next; |
| *next_path = '\0'; |
| } |
| /* Do we already have path? */ |
| path_element = man_path_list; |
| if (path_element) while (*path_element) { |
| if (strcmp(*path_element, path) == 0) |
| goto skip; |
| path_element++; |
| } |
| man_path_list = xrealloc_vector(man_path_list, 4, *count_mp); |
| man_path_list[*count_mp] = xstrdup(path); |
| (*count_mp)++; |
| /* man_path_list is NULL terminated */ |
| /* man_path_list[*count_mp] = NULL; - xrealloc_vector did it */ |
| skip: |
| if (!next_path) |
| break; |
| /* "path" may be a result of getenv(), be nice and don't mangle it */ |
| *next_path = ':'; |
| next: |
| path = next_path + 1; |
| } |
| return man_path_list; |
| } |
| |
| static const char *if_redefined(const char *var, const char *key, const char *line) |
| { |
| if (!is_prefixed_with(line, key)) |
| return var; |
| line += strlen(key); |
| if (!isspace(line[0])) |
| return var; |
| return xstrdup(skip_whitespace(line)); |
| } |
| |
| int man_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int man_main(int argc UNUSED_PARAM, char **argv) |
| { |
| parser_t *parser; |
| char *sec_list; |
| char *cur_path, *cur_sect; |
| char **man_path_list; |
| int count_mp; |
| int cur_mp; |
| int opt, not_found; |
| char *token[2]; |
| |
| INIT_G(); |
| |
| opt_complementary = "-1"; /* at least one argument */ |
| opt = getopt32(argv, "+aw"); |
| argv += optind; |
| |
| sec_list = xstrdup("0p:1:1p:2:3:3p:4:5:6:7:8:9"); |
| |
| count_mp = 0; |
| man_path_list = add_MANPATH(NULL, &count_mp, |
| getenv("MANDATORY_MANPATH"+10) /* "MANPATH" */ |
| ); |
| if (!man_path_list) { |
| /* default, may be overridden by /etc/man.conf */ |
| man_path_list = xzalloc(2 * sizeof(man_path_list[0])); |
| man_path_list[0] = (char*)"/usr/man"; |
| /* count_mp stays 0. |
| * Thus, man.conf will overwrite man_path_list[0] |
| * if a path is defined there. |
| */ |
| } |
| |
| /* Parse man.conf[ig] or man_db.conf */ |
| /* man version 1.6f uses man.config */ |
| /* man-db implementation of man uses man_db.conf */ |
| parser = config_open2("/etc/man.config", fopen_for_read); |
| if (!parser) |
| parser = config_open2("/etc/man.conf", fopen_for_read); |
| if (!parser) |
| parser = config_open2("/etc/man_db.conf", fopen_for_read); |
| |
| while (config_read(parser, token, 2, 0, "# \t", PARSE_NORMAL)) { |
| if (!token[1]) |
| continue; |
| if (strcmp("DEFINE", token[0]) == 0) { |
| G.col = if_redefined(G.tbl , "col", token[1]); |
| G.tbl = if_redefined(G.tbl , "tbl", token[1]); |
| G.nroff = if_redefined(G.nroff, "nroff", token[1]); |
| G.pager = if_redefined(G.pager, "pager", token[1]); |
| } else |
| if (strcmp("MANDATORY_MANPATH"+10, token[0]) == 0 /* "MANPATH"? */ |
| || strcmp("MANDATORY_MANPATH", token[0]) == 0 |
| ) { |
| man_path_list = add_MANPATH(man_path_list, &count_mp, token[1]); |
| } |
| if (strcmp("MANSECT", token[0]) == 0) { |
| free(sec_list); |
| sec_list = xstrdup(token[1]); |
| } |
| } |
| config_close(parser); |
| |
| { |
| /* environment overrides setting from man.config */ |
| char *env_pager = getenv("MANPAGER"); |
| if (!env_pager) |
| env_pager = getenv("PAGER"); |
| if (env_pager) |
| G.pager = env_pager; |
| } |
| |
| if (!isatty(STDOUT_FILENO)) { |
| putenv((char*)"GROFF_NO_SGR=1"); |
| G.pager = xasprintf("%s -b -p -x", G.col); |
| } |
| |
| not_found = 0; |
| do { /* for each argv[] */ |
| int found = 0; |
| cur_mp = 0; |
| |
| if (strchr(*argv, '/')) { |
| found = show_manpage(*argv, /*man:*/ 1, 0); |
| goto check_found; |
| } |
| while ((cur_path = man_path_list[cur_mp++]) != NULL) { |
| /* for each MANPATH */ |
| cur_sect = sec_list; |
| do { /* for each section */ |
| char *next_sect = strchrnul(cur_sect, ':'); |
| int sect_len = next_sect - cur_sect; |
| char *man_filename; |
| int cat0man1 = 0; |
| |
| /* Search for cat, then man page */ |
| while (cat0man1 < 2) { |
| int found_here; |
| man_filename = xasprintf("%s/%s%.*s/%s.%.*s", |
| cur_path, |
| "cat\0man" + (cat0man1 * 4), |
| sect_len, cur_sect, |
| *argv, |
| sect_len, cur_sect); |
| found_here = show_manpage(man_filename, cat0man1, 0); |
| found |= found_here; |
| cat0man1 += found_here + 1; |
| free(man_filename); |
| } |
| |
| if (found && !(opt & OPT_a)) |
| goto next_arg; |
| cur_sect = next_sect; |
| while (*cur_sect == ':') |
| cur_sect++; |
| } while (*cur_sect); |
| } |
| check_found: |
| if (!found) { |
| bb_error_msg("no manual entry for '%s'", *argv); |
| not_found = 1; |
| } |
| next_arg: |
| argv++; |
| } while (*argv); |
| |
| return not_found; |
| } |