X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=miscutils%2Fman.c;h=ba6bb4c01f6df7a2570a37fbab53594cd3e63921;hb=4c9455f967e21d30db0de2e13b6e1115ab8f36ce;hp=b1bb1530a276b238b523e58e3dcfd8c37424427c;hpb=deeed59de0a9bcc068ebd14d7496a6b26e45b890;p=oweals%2Fbusybox.git diff --git a/miscutils/man.c b/miscutils/man.c index b1bb1530a..ba6bb4c01 100644 --- a/miscutils/man.c +++ b/miscutils/man.c @@ -1,9 +1,28 @@ /* mini man implementation for busybox * Copyright (C) 2008 Denys Vlasenko - * Licensed under GPLv2, see file LICENSE in this tarball for details. + * Licensed under GPLv2, see file LICENSE in this source tree. */ +//config:config MAN +//config: bool "man (27 kb)" +//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 */ @@ -11,7 +30,6 @@ enum { }; /* This is what I see on my desktop system being executed: - ( echo ".ll 12.4i" echo ".nr LL 12.4i" @@ -21,16 +39,48 @@ 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=n -rLT=n -Tutf8 | less + +where is screen width minus 5. +Replacing "DEFINE nroff nroff -mandoc" in /etc/man_db.conf +changes "nroff -mandoc" part; -rLL=n, -rLT=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. */ -/* Trick gcc to reuse "cat" string. */ -#define STR_catNULmanNUL "cat\0man" -#define STR_cat "cat\0man" +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(const char *unpacker, const char *pager, char *man_filename, int man) +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; @@ -39,143 +89,274 @@ static int run_pipe(const char *unpacker, const char *pager, char *man_filename, return 1; } - /* "2>&1" is added so that nroff errors are shown in pager too. - * Otherwise it may show just empty screen */ - cmd = xasprintf( - man ? "%s '%s' | gtbl | nroff -Tlatin1 -mandoc 2>&1 | %s" - : "%s '%s' | %s", - unpacker, man_filename, pager); + 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" + */ + *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.bz2" */ -static int show_manpage(const char *pager, char *man_filename, int man) +/* man_filename is of the form "/dir/dir/dir/name.s" */ +static int show_manpage(char *man_filename, int man, int level) { - int len; +#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 (run_pipe("bunzip2 -c", pager, man_filename, man)) +#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 - len = strlen(man_filename) - 1; + return run_pipe(man_filename, man, level); +} - man_filename[len] = '\0'; /* ".bz2" -> ".gz" */ - man_filename[len - 2] = 'g'; - if (run_pipe("gunzip -c", pager, man_filename, man)) - return 1; +static char **add_MANPATH(char **man_path_list, int *count_mp, char *path) +{ + if (path) while (*path) { + char *next_path; + char **path_element; - man_filename[len - 3] = '\0'; /* ".gz" -> "" */ - if (run_pipe(STR_cat, pager, man_filename, man)) - return 1; + 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; +} - return 0; +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) { - FILE *cf; - const char *pager; - char **man_path_list; + parser_t *parser; char *sec_list; char *cur_path, *cur_sect; - char *line, *value; - int count_mp, cur_mp; + 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"); + opt = getopt32(argv, "^+" "aw" "\0" "-1"/*at least one arg*/); argv += optind; - sec_list = xstrdup("1:2:3:4:5:6:7:8:9"); - /* Last valid man_path_list[] is [0x10] */ - man_path_list = xzalloc(0x11 * sizeof(man_path_list[0])); + sec_list = xstrdup("0p:1:1p:2:3:3p:4:5:6:7:8:9"); + count_mp = 0; - man_path_list[0] = xstrdup(getenv("MANPATH")); - if (man_path_list[0]) - count_mp++; - pager = getenv("MANPAGER"); - if (!pager) { - pager = getenv("PAGER"); - if (!pager) - pager = "more"; + 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 */ - cf = fopen_or_warn("/etc/man.conf", "r"); - if (cf) { - /* go through man configuration file and search relevant paths, sections */ - while ((line = xmalloc_fgetline(cf)) != NULL) { - trim(line); /* remove whitespace at the beginning/end */ - if (isspace(line[7])) { - line[7] = '\0'; - value = skip_whitespace(&line[8]); - *skip_non_whitespace(value) = '\0'; - if (strcmp("MANPATH", line) == 0) { - man_path_list[count_mp] = xstrdup(value); - count_mp++; - /* man_path_list is NULL terminated */ - man_path_list[count_mp] = NULL; - man_path_list = xrealloc_vector(man_path_list, 4, count_mp); - } - if (strcmp("MANSECT", line) == 0) { - free(sec_list); - sec_list = xstrdup(value); - } - } - free(line); + /* 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]); } - fclose(cf); } + config_close(parser); -// TODO: my man3/getpwuid.3.gz contains just one line: -// .so man3/getpwnam.3 -// (and I _dont_ have man3/getpwnam.3, I have man3/getpwnam.3.gz) -// need to support this... + { + /* 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 */ - do { /* for each MANPATH item */ - char *next_path = strchrnul(cur_path, ':'); - int path_len = next_path - cur_path; - 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" ".bz2", - path_len, cur_path, - STR_catNULmanNUL + cat0man1 * 4, - sect_len, cur_sect, - *argv, - sect_len, cur_sect); - found_here = show_manpage(pager, man_filename, cat0man1); - 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); - cur_path = next_path; - while (*cur_path == ':') - cur_path++; - } while (*cur_path); + 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;