1 /* vi: set sw=4 ts=4: */
5 * Copyright (C) tons of folks. Tracking down who wrote what
6 * isn't something I'm going to worry about... If you wrote something
7 * here, please feel free to acknowledge your work.
9 * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
10 * Permission has been granted to redistribute this code under GPL.
12 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
14 /* We are trying to not use printf, this benefits the case when selected
15 * applets are really simple. Example:
19 * Currently defined functions:
20 * basename, false, true
23 * text data bss dec hex filename
24 * 4473 52 72 4597 11f5 busybox
26 * FEATURE_INSTALLER or FEATURE_SUID will still link printf routines in. :(
30 #if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
31 || defined(__APPLE__) \
33 # include <malloc.h> /* for mallopt */
36 /* Declare <applet>_main() */
41 /* Include generated applet names, pointers to <applet>_main, etc */
42 #include "applet_tables.h"
43 /* ...and if applet_tables generator says we have only one applet... */
44 #ifdef SINGLE_APPLET_MAIN
45 # undef ENABLE_FEATURE_INDIVIDUAL
46 # define ENABLE_FEATURE_INDIVIDUAL 1
47 # undef IF_FEATURE_INDIVIDUAL
48 # define IF_FEATURE_INDIVIDUAL(...) __VA_ARGS__
51 #include "usage_compressed.h"
53 #if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS
54 # define DEFINE_SCRIPT_DATA 1
55 # include "embedded_scripts.h"
57 # define NUM_SCRIPTS 0
60 # include "bb_archive.h"
61 static const char packed_scripts[] ALIGN1 = { PACKED_SCRIPTS };
64 /* "Do not compress usage text if uncompressed text is small
65 * and we don't include bunzip2 code for other reasons"
67 * Useful for mass one-applet rebuild (bunzip2 code is ~2.7k).
69 * Unlike BUNZIP2, if FEATURE_SEAMLESS_BZ2 is on, bunzip2 code is built but
70 * still may be unused if none of the selected applets calls open_zipped()
71 * or its friends; we test for (FEATURE_SEAMLESS_BZ2 && <APPLET>) instead.
72 * For example, only if TAR and FEATURE_SEAMLESS_BZ2 are both selected,
73 * then bunzip2 code will be linked in anyway, and disabling help compression
74 * would be not optimal:
76 #if UNPACKED_USAGE_LENGTH < 4*1024 \
77 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_TAR) \
78 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_MODPROBE) \
79 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_INSMOD) \
80 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_DEPMOD) \
81 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_MAN) \
84 # undef ENABLE_FEATURE_COMPRESS_USAGE
85 # define ENABLE_FEATURE_COMPRESS_USAGE 0
89 unsigned FAST_FUNC string_array_len(char **argv)
100 #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
101 static const char usage_messages[] ALIGN1 = UNPACKED_USAGE;
103 # define usage_messages 0
106 #if ENABLE_FEATURE_COMPRESS_USAGE
108 static const char packed_usage[] ALIGN1 = { PACKED_USAGE };
109 # include "bb_archive.h"
110 # define unpack_usage_messages() \
111 unpack_bz2_data(packed_usage, sizeof(packed_usage), sizeof(UNPACKED_USAGE))
112 # define dealloc_usage_messages(s) free(s)
116 # define unpack_usage_messages() usage_messages
117 # define dealloc_usage_messages(s) ((void)(s))
119 #endif /* FEATURE_COMPRESS_USAGE */
122 void FAST_FUNC bb_show_usage(void)
124 if (ENABLE_SHOW_USAGE) {
125 #ifdef SINGLE_APPLET_STR
126 /* Imagine that this applet is "true". Dont link in printf! */
127 const char *usage_string = unpack_usage_messages();
130 if (*usage_string == '\b') {
131 full_write2_str("No help available\n");
133 full_write2_str("Usage: "SINGLE_APPLET_STR" ");
134 full_write2_str(usage_string);
135 full_write2_str("\n");
137 if (ENABLE_FEATURE_CLEAN_UP)
138 dealloc_usage_messages((char*)usage_string);
142 const char *usage_string = p = unpack_usage_messages();
143 int ap = find_applet_by_name(applet_name);
145 if (ap < 0 || usage_string == NULL)
148 while (*p++) continue;
151 full_write2_str(bb_banner);
152 full_write2_str(" multi-call binary.\n"); /* common string */
154 full_write2_str("\nNo help available\n");
156 full_write2_str("\nUsage: ");
157 full_write2_str(applet_name);
160 full_write2_str(" ");
163 full_write2_str("\n");
165 if (ENABLE_FEATURE_CLEAN_UP)
166 dealloc_usage_messages((char*)usage_string);
172 int FAST_FUNC find_applet_by_name(const char *name)
178 /* The commented-out word-at-a-time code is ~40% faster, but +160 bytes.
179 * "Faster" here saves ~0.5 microsecond of real time - not worth it.
181 #if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
184 /* Handle all names < 2 chars long early */
186 return -1; /* "" is not a valid applet name */
187 if (name[1] == '\0') {
189 return -1; /* 1-char name is not valid */
191 return -1; /* 1-char name which isn't "[" is not valid */
192 /* applet "[" is always applet #0: */
199 #if KNOWN_APPNAME_OFFSETS <= 0
202 max = NUM_APPLETS * KNOWN_APPNAME_OFFSETS;
203 for (j = ARRAY_SIZE(applet_nameofs)-1; j >= 0; j--) {
204 const char *pp = applet_names + applet_nameofs[j];
205 if (strcmp(name, pp) >= 0) {
206 //bb_error_msg("name:'%s' >= pp:'%s'", name, pp);
208 i = max - NUM_APPLETS;
213 max /= (unsigned)KNOWN_APPNAME_OFFSETS;
214 i /= (unsigned)KNOWN_APPNAME_OFFSETS;
215 //bb_error_msg("name:'%s' starting from:'%s' i:%u max:%u", name, p, i, max);
218 /* Open-coded linear search without strcmp/strlen calls for speed */
220 #if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
221 /* skip "[\0" name, it's surely not it */
222 if (ENABLE_TEST && LONE_CHAR(p, '['))
224 /* All remaining applet names in p[] are at least 2 chars long */
225 /* name[] is also at least 2 chars long */
227 n32 = (name[0] << 0) | (name[1] << 8) | (name[2] << 16);
232 /* Quickly check match of the first 3 bytes */
233 move_from_unaligned32(p32, p);
235 if ((p32 & 0x00ffffff) != n32) {
236 /* Most likely case: 3 first bytes do not match */
238 if ((p32 & 0x00ff0000) == '\0')
239 continue; // p[2] was NUL
241 if ((p32 & 0xff000000) == '\0')
242 continue; // p[3] was NUL
243 /* p[0..3] aren't matching and none is NUL, check the rest */
249 /* Unlikely branch: first 3 bytes ([0..2]) match */
250 if ((p32 & 0x00ff0000) == '\0') {
251 /* name is 2-byte long, it is full match */
252 //bb_error_msg("found:'%s' i:%u", name, i);
255 /* Check remaining bytes [3..NUL] */
258 while (ch == name[j]) {
260 //bb_error_msg("found:'%s' i:%u", name, i);
266 /* Not a match. Skip it, including NUL */
277 /* Do we see "name\0" in applet_names[p] position? */
278 while ((ch = *p) == name[j]) {
280 //bb_error_msg("found:'%s' i:%u", name, i);
287 * p => 1st non-matching char in applet_names[],
288 * skip to and including NUL.
300 void lbb_prepare(const char *applet
301 IF_FEATURE_INDIVIDUAL(, char **argv))
302 MAIN_EXTERNALLY_VISIBLE;
303 void lbb_prepare(const char *applet
304 IF_FEATURE_INDIVIDUAL(, char **argv))
307 (*(int **)not_const_pp(&bb_errno)) = __errno_location();
310 applet_name = applet;
312 if (ENABLE_LOCALE_SUPPORT)
313 setlocale(LC_ALL, "");
315 #if ENABLE_FEATURE_INDIVIDUAL
316 /* Redundant for busybox (run_applet_and_exit covers that case)
317 * but needed for "individual applet" mode */
320 && strcmp(argv[1], "--help") == 0
321 && !is_prefixed_with(applet, "busybox")
323 /* Special case. POSIX says "test --help"
324 * should be no different from e.g. "test --foo". */
325 if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
331 /* The code below can well be in applets/applets.c, as it is used only
332 * for busybox binary, not "individual" binaries.
333 * However, keeping it here and linking it into libbusybox.so
334 * (together with remaining tiny applets/applets.o)
335 * makes it possible to avoid --whole-archive at link time.
336 * This makes (shared busybox) + libbusybox smaller.
337 * (--gc-sections would be even better....)
340 const char *applet_name;
346 /* If not built as a single-applet executable... */
347 #if !defined(SINGLE_APPLET_MAIN)
349 IF_FEATURE_SUID(static uid_t ruid;) /* real uid */
351 # if ENABLE_FEATURE_SUID_CONFIG
353 static struct suid_config_t {
354 /* next ptr must be first: this struct needs to be llist-compatible */
355 struct suid_config_t *m_next;
356 struct bb_uidgid_t m_ugid;
361 static bool suid_cfg_readable;
363 /* libbb candidate */
364 static char *get_trimmed_slice(char *s, char *e)
366 /* First, consider the value at e to be nul and back up until we
367 * reach a non-space char. Set the char after that (possibly at
368 * the original e) to nul. */
376 /* Next, advance past all leading space and return a ptr to the
377 * first non-space char; possibly the terminating nul. */
378 return skip_whitespace(s);
381 static void parse_config_file(void)
383 /* Don't depend on the tools to combine strings. */
384 static const char config_file[] ALIGN1 = "/etc/busybox.conf";
386 struct suid_config_t *sct_head;
395 if (ruid == 0) /* run by root - don't need to even read config file */
398 if ((stat(config_file, &st) != 0) /* No config file? */
399 || !S_ISREG(st.st_mode) /* Not a regular file? */
400 || (st.st_uid != 0) /* Not owned by root? */
401 || (st.st_mode & (S_IWGRP | S_IWOTH)) /* Writable by non-root? */
402 || !(f = fopen_for_read(config_file)) /* Cannot open? */
407 suid_cfg_readable = 1;
415 if (!fgets(buffer, sizeof(buffer), f)) { /* Are we done? */
417 //if (ferror(f)) { /* Make sure it wasn't a read error. */
418 // errmsg = "reading";
422 suid_config = sct_head; /* Success, so set the pointer. */
427 lc++; /* Got a (partial) line. */
429 /* If a line is too long for our buffer, we consider it an error.
430 * The following test does mistreat one corner case though.
431 * If the final line of the file does not end with a newline and
432 * yet exactly fills the buffer, it will be treated as too long
433 * even though there isn't really a problem. But it isn't really
434 * worth adding code to deal with such an unlikely situation, and
435 * we do err on the side of caution. Besides, the line would be
436 * too long if it did end with a newline. */
437 if (!strchr(s, '\n') && !feof(f)) {
438 errmsg = "line too long";
442 /* Trim leading and trailing whitespace, ignoring comments, and
443 * check if the resulting string is empty. */
444 s = get_trimmed_slice(s, strchrnul(s, '#'));
449 /* Check for a section header. */
452 /* Unlike the old code, we ignore leading and trailing
453 * whitespace for the section name. We also require that
454 * there are no stray characters after the closing bracket. */
455 char *e = strchr(s, ']');
456 if (!e /* Missing right bracket? */
457 || e[1] /* Trailing characters? */
458 || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
460 errmsg = "section header";
463 /* Right now we only have one section so just check it.
464 * If more sections are added in the future, please don't
465 * resort to cascading ifs with multiple strcasecmp calls.
466 * That kind of bloated code is all too common. A loop
467 * and a string table would be a better choice unless the
468 * number of sections is very small. */
469 if (strcasecmp(s, "SUID") == 0) {
473 section = -1; /* Unknown section so set to skip. */
477 /* Process sections. */
479 if (section == 1) { /* SUID */
480 /* Since we trimmed leading and trailing space above, we're
481 * now looking for strings of the form
482 * <key>[::space::]*=[::space::]*<value>
483 * where both key and value could contain inner whitespace. */
485 /* First get the key (an applet name in our case). */
486 char *e = strchr(s, '=');
488 s = get_trimmed_slice(s, e);
490 if (!e || !*s) { /* Missing '=' or empty key. */
495 /* Ok, we have an applet name. Process the rhs if this
496 * applet is currently built in and ignore it otherwise.
497 * Note: this can hide config file bugs which only pop
498 * up when the busybox configuration is changed. */
499 applet_no = find_applet_by_name(s);
500 if (applet_no >= 0) {
502 struct suid_config_t *sct;
504 /* Note: We currently don't check for duplicates!
505 * The last config line for each applet will be the
506 * one used since we insert at the head of the list.
507 * I suppose this could be considered a feature. */
508 sct = xzalloc(sizeof(*sct));
509 sct->m_applet = applet_no;
511 sct->m_next = sct_head;
514 /* Get the specified mode. */
516 e = skip_whitespace(e+1);
518 for (i = 0; i < 3; i++) {
519 /* There are 4 chars for each of user/group/other.
520 * "x-xx" instead of "x-" are to make
521 * "idx > 3" check catch invalid chars.
523 static const char mode_chars[] ALIGN1 = "Ssx-" "Ssx-" "x-xx";
524 static const unsigned short mode_mask[] ALIGN2 = {
525 S_ISUID, S_ISUID|S_IXUSR, S_IXUSR, 0, /* Ssx- */
526 S_ISGID, S_ISGID|S_IXGRP, S_IXGRP, 0, /* Ssx- */
529 const char *q = strchrnul(mode_chars + 4*i, *e);
530 unsigned idx = q - (mode_chars + 4*i);
535 sct->m_mode |= mode_mask[q - mode_chars];
539 /* Now get the user/group info. */
541 s = skip_whitespace(e);
542 /* Default is 0.0, else parse USER.GROUP: */
544 /* We require whitespace between mode and USER.GROUP */
545 if ((s == e) || !(e = strchr(s, '.'))) {
549 *e = ':'; /* get_uidgid needs USER:GROUP syntax */
550 if (get_uidgid(&sct->m_ugid, s) == 0) {
551 errmsg = "unknown user/group";
559 /* Unknown sections are ignored. */
561 /* Encountering configuration lines prior to seeing a
562 * section header is treated as an error. This is how
563 * the old code worked, but it may not be desirable.
564 * We may want to simply ignore such lines in case they
565 * are used in some future version of busybox. */
567 errmsg = "keyword outside section";
574 bb_error_msg("parse error in %s, line %u: %s", config_file, lc, errmsg);
576 /* Release any allocated memory before returning. */
577 llist_free((llist_t*)sct_head, NULL);
580 static inline void parse_config_file(void)
582 IF_FEATURE_SUID(ruid = getuid();)
584 # endif /* FEATURE_SUID_CONFIG */
587 # if ENABLE_FEATURE_SUID && NUM_APPLETS > 0
588 # if ENABLE_FEATURE_SUID_CONFIG
589 /* check if u is member of group g */
590 static int ingroup(uid_t u, gid_t g)
592 struct group *grp = getgrgid(g);
595 for (mem = grp->gr_mem; *mem; mem++) {
596 struct passwd *pwd = getpwnam(*mem);
597 if (pwd && (pwd->pw_uid == u))
605 static void check_suid(int applet_no)
607 gid_t rgid; /* real gid */
609 if (ruid == 0) /* set by parse_config_file() */
610 return; /* run by root - no need to check more */
613 # if ENABLE_FEATURE_SUID_CONFIG
614 if (suid_cfg_readable) {
616 struct suid_config_t *sct;
619 for (sct = suid_config; sct; sct = sct->m_next) {
620 if (sct->m_applet == applet_no)
623 goto check_need_suid;
625 /* Is this user allowed to run this applet? */
627 if (sct->m_ugid.uid == ruid)
630 else if ((sct->m_ugid.gid == rgid) || ingroup(ruid, sct->m_ugid.gid))
631 /* same group / in group */
633 if (!(m & S_IXOTH)) /* is x bit not set? */
634 bb_simple_error_msg_and_die("you have no permission to run this applet");
636 /* We set effective AND saved ids. If saved-id is not set
637 * like we do below, seteuid(0) can still later succeed! */
639 /* Are we directed to change gid
640 * (APPLET = *s* USER.GROUP or APPLET = *S* USER.GROUP)?
642 if (sct->m_mode & S_ISGID)
643 rgid = sct->m_ugid.gid;
644 /* else: we will set egid = rgid, thus dropping sgid effect */
645 if (setresgid(-1, rgid, rgid))
646 bb_simple_perror_msg_and_die("setresgid");
648 /* Are we directed to change uid
649 * (APPLET = s** USER.GROUP or APPLET = S** USER.GROUP)?
652 if (sct->m_mode & S_ISUID)
653 uid = sct->m_ugid.uid;
654 /* else: we will set euid = ruid, thus dropping suid effect */
655 if (setresuid(-1, uid, uid))
656 bb_simple_perror_msg_and_die("setresuid");
660 # if !ENABLE_FEATURE_SUID_CONFIG_QUIET
662 static bool onetime = 0;
666 bb_simple_error_msg("using fallback suid method");
672 if (APPLET_SUID(applet_no) == BB_SUID_REQUIRE) {
673 /* Real uid is not 0. If euid isn't 0 too, suid bit
674 * is most probably not set on our executable */
676 bb_simple_error_msg_and_die("must be suid to work properly");
677 } else if (APPLET_SUID(applet_no) == BB_SUID_DROP) {
679 * Drop all privileges.
681 * Don't check for errors: in normal use, they are impossible,
682 * and in special cases, exiting is harmful. Example:
683 * 'unshare --user' when user's shell is also from busybox.
685 * 'unshare --user' creates a new user namespace without any
686 * uid mappings. Thus, busybox binary is setuid nobody:nogroup
687 * within the namespace, as that is the only user. However,
688 * since no uids are mapped, calls to setgid/setuid
689 * fail (even though they would do nothing).
694 # if ENABLE_FEATURE_SUID_CONFIG
696 llist_free((llist_t*)suid_config, NULL);
700 # define check_suid(x) ((void)0)
701 # endif /* FEATURE_SUID */
704 # if ENABLE_FEATURE_INSTALLER
705 static const char usr_bin [] ALIGN1 = "/usr/bin/";
706 static const char usr_sbin[] ALIGN1 = "/usr/sbin/";
707 static const char *const install_dir[] = {
708 &usr_bin [8], /* "/" */
709 &usr_bin [4], /* "/bin/" */
710 &usr_sbin[4] /* "/sbin/" */
711 # if !ENABLE_INSTALL_NO_USR
717 /* create (sym)links for each applet */
718 static void install_links(const char *busybox, int use_symbolic_links,
719 char *custom_install_dir)
722 * this should be consistent w/ the enum,
723 * busybox.h::bb_install_loc_t, or else... */
724 int (*lf)(const char *, const char *);
726 const char *appname = applet_names;
731 if (use_symbolic_links)
734 for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
735 fpc = concat_path_file(
736 custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
738 // debug: bb_error_msg("%slinking %s to busybox",
739 // use_symbolic_links ? "sym" : "", fpc);
740 rc = lf(busybox, fpc);
741 if (rc != 0 && errno != EEXIST) {
742 bb_simple_perror_msg(fpc);
745 while (*appname++ != '\0')
749 # elif ENABLE_BUSYBOX
750 static void install_links(const char *busybox UNUSED_PARAM,
751 int use_symbolic_links UNUSED_PARAM,
752 char *custom_install_dir UNUSED_PARAM)
757 # if ENABLE_BUSYBOX || NUM_APPLETS > 0
758 static void run_applet_and_exit(const char *name, char **argv) NORETURN;
762 static int find_script_by_name(const char *name)
765 int applet = find_applet_by_name(name);
768 for (i = 0; i < NUM_SCRIPTS; ++i)
769 if (applet_numbers[i] == applet)
775 int scripted_main(int argc UNUSED_PARAM, char **argv) MAIN_EXTERNALLY_VISIBLE;
776 int scripted_main(int argc UNUSED_PARAM, char **argv)
778 int script = find_script_by_name(applet_name);
780 # if ENABLE_SHELL_ASH
781 exit(ash_main(-script - 1, argv));
782 # elif ENABLE_SHELL_HUSH
783 exit(hush_main(-script - 1, argv));
791 get_script_content(unsigned n)
793 char *t = unpack_bz2_data(packed_scripts, sizeof(packed_scripts),
794 UNPACKED_SCRIPTS_LENGTH);
804 # endif /* NUM_SCRIPTS > 0 */
807 # if ENABLE_FEATURE_SH_STANDALONE && ENABLE_FEATURE_TAB_COMPLETION
809 * Insert "busybox" into applet table as well.
810 * This makes standalone shell tab-complete this name too.
811 * (Otherwise having "busybox" in applet table is not necessary,
812 * there is other code which routes "busyboxANY_SUFFIX" name
813 * to busybox_main()).
815 //usage:#define busybox_trivial_usage NOUSAGE_STR
816 //usage:#define busybox_full_usage ""
817 //applet:IF_BUSYBOX(IF_FEATURE_SH_STANDALONE(IF_FEATURE_TAB_COMPLETION(APPLET(busybox, BB_DIR_BIN, BB_SUID_MAYBE))))
818 int busybox_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
820 # define busybox_main(argc,argv) busybox_main(argv)
823 int busybox_main(int argc UNUSED_PARAM, char **argv)
826 /* Called without arguments */
829 unsigned output_width;
831 output_width = get_terminal_width(2);
834 full_write2_str(bb_banner); /* reuse const string */
835 full_write2_str(" multi-call binary.\n"); /* reuse */
837 "BusyBox is copyrighted by many authors between 1998-2015.\n"
838 "Licensed under GPLv2. See source distribution for detailed\n"
839 "copyright notices.\n"
841 "Usage: busybox [function [arguments]...]\n"
842 " or: busybox --list"IF_FEATURE_INSTALLER("[-full]")"\n"
843 # if ENABLE_FEATURE_SHOW_SCRIPT && NUM_SCRIPTS > 0
844 " or: busybox --show SCRIPT\n"
846 IF_FEATURE_INSTALLER(
847 " or: busybox --install [-s] [DIR]\n"
849 " or: function [arguments]...\n"
851 IF_NOT_FEATURE_SH_STANDALONE(
852 "\tBusyBox is a multi-call binary that combines many common Unix\n"
853 "\tutilities into a single executable. Most people will create a\n"
854 "\tlink to busybox for each function they wish to use and BusyBox\n"
855 "\twill act like whatever it was invoked as.\n"
857 IF_FEATURE_SH_STANDALONE(
858 "\tBusyBox is a multi-call binary that combines many common Unix\n"
859 "\tutilities into a single executable. The shell in this build\n"
860 "\tis configured to run built-in utilities without $PATH search.\n"
861 "\tYou don't need to install a link to busybox for each utility.\n"
862 "\tTo run external program, use full path (/sbin/ip instead of ip).\n"
865 "Currently defined functions:\n"
868 /* prevent last comma to be in the very last pos */
872 int len2 = strlen(a) + 2;
873 if (col >= (int)output_width - len2) {
874 full_write2_str(",\n");
879 full_write2_str("\t");
881 full_write2_str(", ");
887 full_write2_str("\n");
891 # if ENABLE_FEATURE_SHOW_SCRIPT && NUM_SCRIPTS > 0
892 if (strcmp(argv[1], "--show") == 0) {
895 bb_error_msg_and_die(bb_msg_requires_arg, "--show");
896 n = find_script_by_name(argv[2]);
898 bb_error_msg_and_die("script '%s' not found", argv[2]);
899 full_write1_str(get_script_content(n));
904 if (is_prefixed_with(argv[1], "--list")) {
906 const char *a = applet_names;
909 # if ENABLE_FEATURE_INSTALLER
910 if (argv[1][6]) /* --list-full? */
911 full_write2_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
914 full_write2_str("\n");
922 if (ENABLE_FEATURE_INSTALLER && strcmp(argv[1], "--install") == 0) {
923 int use_symbolic_links;
926 busybox = xmalloc_readlink(bb_busybox_exec_path);
928 /* bb_busybox_exec_path is usually "/proc/self/exe".
929 * In chroot, readlink("/proc/self/exe") usually fails.
930 * In such case, better use argv[0] as symlink target
931 * if it is a full path name.
933 if (argv[0][0] != '/')
934 bb_error_msg_and_die("'%s' is not an absolute path", argv[0]);
937 /* busybox --install [-s] [DIR]:
939 * DIR: directory to install links to
941 use_symbolic_links = (argv[2] && strcmp(argv[2], "-s") == 0 && ++argv);
942 install_links(busybox, use_symbolic_links, argv[2]);
946 if (strcmp(argv[1], "--help") == 0) {
947 /* "busybox --help [<applet>]" */
950 /* convert to "<applet> --help" */
954 /* "busybox <applet> arg1 arg2 ..." */
957 /* We support "busybox /a/path/to/applet args..." too. Allows for
958 * "#!/bin/busybox"-style wrappers */
959 applet_name = bb_get_last_path_component_nostrip(argv[0]);
960 run_applet_and_exit(applet_name, argv);
965 void FAST_FUNC run_applet_no_and_exit(int applet_no, const char *name, char **argv)
967 int argc = string_array_len(argv);
970 * We do not use argv[0]: do not want to repeat massaging of
971 * "-/sbin/halt" -> "halt", for example.
975 /* Special case. POSIX says "test --help"
976 * should be no different from e.g. "test --foo".
977 * Thus for "test", we skip --help check.
978 * "true" and "false" are also special.
981 # if defined APPLET_NO_test
982 && applet_no != APPLET_NO_test
984 # if defined APPLET_NO_true
985 && applet_no != APPLET_NO_true
987 # if defined APPLET_NO_false
988 && applet_no != APPLET_NO_false
991 if (argc == 2 && strcmp(argv[1], "--help") == 0) {
992 /* Make "foo --help" exit with 0: */
993 xfunc_error_retval = 0;
997 if (ENABLE_FEATURE_SUID)
998 check_suid(applet_no);
999 xfunc_error_retval = applet_main[applet_no](argc, argv);
1000 /* Note: applet_main() may also not return (die on a xfunc or such) */
1003 # endif /* NUM_APPLETS > 0 */
1005 # if ENABLE_BUSYBOX || NUM_APPLETS > 0
1006 static NORETURN void run_applet_and_exit(const char *name, char **argv)
1009 if (is_prefixed_with(name, "busybox"))
1010 exit(busybox_main(/*unused:*/ 0, argv));
1012 # if NUM_APPLETS > 0
1013 /* find_applet_by_name() search is more expensive, so goes second */
1015 int applet = find_applet_by_name(name);
1017 run_applet_no_and_exit(applet, name, argv);
1021 /*bb_error_msg_and_die("applet not found"); - links in printf */
1022 full_write2_str(applet_name);
1023 full_write2_str(": applet not found\n");
1024 /* POSIX: "If a command is not found, the exit status shall be 127" */
1029 #else /* defined(SINGLE_APPLET_MAIN) */
1031 # if NUM_SCRIPTS > 0
1032 /* if SINGLE_APPLET_MAIN, these two functions are simpler: */
1033 int scripted_main(int argc UNUSED_PARAM, char **argv) MAIN_EXTERNALLY_VISIBLE;
1034 int scripted_main(int argc UNUSED_PARAM, char **argv)
1036 # if ENABLE_SHELL_ASH
1038 exit(ash_main(-script - 1, argv));
1039 # elif ENABLE_SHELL_HUSH
1041 exit(hush_main(-script - 1, argv));
1047 get_script_content(unsigned n UNUSED_PARAM)
1049 char *t = unpack_bz2_data(packed_scripts, sizeof(packed_scripts),
1050 UNPACKED_SCRIPTS_LENGTH);
1053 # endif /* NUM_SCRIPTS > 0 */
1055 #endif /* defined(SINGLE_APPLET_MAIN) */
1058 #if ENABLE_BUILD_LIBBUSYBOX
1059 int lbb_main(char **argv)
1061 int main(int argc UNUSED_PARAM, char **argv)
1065 /* TODO: find a use for a block of memory between end of .bss
1066 * and end of page. For example, I'm getting "_end:0x812e698 2408 bytes"
1067 * - more than 2k of wasted memory (in this particular build)
1068 * *per each running process*!
1069 * (If your linker does not generate "_end" name, weak attribute
1070 * makes &_end == NULL, end_len == 0 here.)
1072 extern char _end[] __attribute__((weak));
1073 unsigned end_len = (-(int)_end) & 0xfff;
1074 printf("_end:%p %u bytes\n", &_end, end_len);
1077 /* Tweak malloc for reduced memory consumption */
1078 #ifdef M_TRIM_THRESHOLD
1079 /* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
1080 * to keep before releasing to the OS
1081 * Default is way too big: 256k
1083 mallopt(M_TRIM_THRESHOLD, 8 * 1024);
1085 #ifdef M_MMAP_THRESHOLD
1086 /* M_MMAP_THRESHOLD is the request size threshold for using mmap()
1087 * Default is too big: 256k
1089 mallopt(M_MMAP_THRESHOLD, 32 * 1024 - 256);
1091 #if 0 /*def M_TOP_PAD*/
1092 /* When the program break is increased, then M_TOP_PAD bytes are added
1093 * to the sbrk(2) request. When the heap is trimmed because of free(3),
1094 * this much free space is preserved at the top of the heap.
1095 * glibc default seems to be way too big: 128k, but need to verify.
1097 mallopt(M_TOP_PAD, 8 * 1024);
1101 /* NOMMU re-exec trick sets high-order bit in first byte of name */
1102 if (argv[0][0] & 0x80) {
1108 #if defined(SINGLE_APPLET_MAIN)
1110 /* Only one applet is selected in .config */
1111 if (argv[1] && is_prefixed_with(argv[0], "busybox")) {
1112 /* "busybox <applet> <params>" should still work as expected */
1115 /* applet_names in this case is just "applet\0\0" */
1116 lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
1117 # if ENABLE_BUILD_LIBBUSYBOX
1118 return SINGLE_APPLET_MAIN(string_array_len(argv), argv);
1120 return SINGLE_APPLET_MAIN(argc, argv);
1123 #elif !ENABLE_BUSYBOX && NUM_APPLETS == 0
1125 full_write2_str(bb_basename(argv[0]));
1126 full_write2_str(": no applets enabled\n");
1131 lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
1132 # if !ENABLE_BUSYBOX
1133 if (argv[1] && is_prefixed_with(bb_basename(argv[0]), "busybox"))
1136 applet_name = argv[0];
1137 if (applet_name[0] == '-')
1139 applet_name = bb_basename(applet_name);
1141 /* If we are a result of execv("/proc/self/exe"), fix ugly comm of "exe" */
1142 if (ENABLE_FEATURE_SH_STANDALONE
1143 || ENABLE_FEATURE_PREFER_APPLETS
1146 if (NUM_APPLETS > 1)
1147 set_task_comm(applet_name);
1150 parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
1151 run_applet_and_exit(applet_name, argv);