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"
54 /* "Do not compress usage text if uncompressed text is small
55 * and we don't include bunzip2 code for other reasons"
57 * Useful for mass one-applet rebuild (bunzip2 code is ~2.7k).
59 * Unlike BUNZIP2, if FEATURE_SEAMLESS_BZ2 is on, bunzip2 code is built but
60 * still may be unused if none of the selected applets calls open_zipped()
61 * or its friends; we test for (FEATURE_SEAMLESS_BZ2 && <APPLET>) instead.
62 * For example, only if TAR and FEATURE_SEAMLESS_BZ2 are both selected,
63 * then bunzip2 code will be linked in anyway, and disabling help compression
64 * would be not optimal:
66 #if UNPACKED_USAGE_LENGTH < 4*1024 \
67 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_TAR) \
68 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_MODPROBE) \
69 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_INSMOD) \
70 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_DEPMOD) \
71 && !(ENABLE_FEATURE_SEAMLESS_BZ2 && ENABLE_MAN) \
74 # undef ENABLE_FEATURE_COMPRESS_USAGE
75 # define ENABLE_FEATURE_COMPRESS_USAGE 0
79 unsigned FAST_FUNC string_array_len(char **argv)
90 #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
91 static const char usage_messages[] ALIGN1 = UNPACKED_USAGE;
93 # define usage_messages 0
96 #if ENABLE_FEATURE_COMPRESS_USAGE
98 static const char packed_usage[] ALIGN1 = { PACKED_USAGE };
99 # include "bb_archive.h"
100 static const char *unpack_usage_messages(void)
107 /* Setup for I/O error handling via longjmp */
110 i = start_bunzip(&jmpbuf,
113 /* inbuf: */ packed_usage,
114 /* len: */ sizeof(packed_usage)
117 /* read_bunzip can longjmp and end up here with i != 0
118 * on read data errors! Not trivial */
120 /* Cannot use xmalloc: will leak bd in NOFORK case! */
121 outbuf = malloc_or_warn(sizeof(UNPACKED_USAGE));
123 read_bunzip(bd, outbuf, sizeof(UNPACKED_USAGE));
128 # define dealloc_usage_messages(s) free(s)
132 # define unpack_usage_messages() usage_messages
133 # define dealloc_usage_messages(s) ((void)(s))
135 #endif /* FEATURE_COMPRESS_USAGE */
138 void FAST_FUNC bb_show_usage(void)
140 if (ENABLE_SHOW_USAGE) {
141 #ifdef SINGLE_APPLET_STR
142 /* Imagine that this applet is "true". Dont suck in printf! */
143 const char *usage_string = unpack_usage_messages();
145 if (*usage_string == '\b') {
146 full_write2_str("No help available.\n\n");
148 full_write2_str("Usage: "SINGLE_APPLET_STR" ");
149 full_write2_str(usage_string);
150 full_write2_str("\n\n");
152 if (ENABLE_FEATURE_CLEAN_UP)
153 dealloc_usage_messages((char*)usage_string);
156 const char *usage_string = p = unpack_usage_messages();
157 int ap = find_applet_by_name(applet_name);
159 if (ap < 0) /* never happens, paranoia */
162 while (*p++) continue;
165 full_write2_str(bb_banner);
166 full_write2_str(" multi-call binary.\n");
168 full_write2_str("\nNo help available.\n\n");
170 full_write2_str("\nUsage: ");
171 full_write2_str(applet_name);
174 full_write2_str(" ");
177 full_write2_str("\n");
179 if (ENABLE_FEATURE_CLEAN_UP)
180 dealloc_usage_messages((char*)usage_string);
186 int FAST_FUNC find_applet_by_name(const char *name)
192 /* The commented-out word-at-a-time code is ~40% faster, but +160 bytes.
193 * "Faster" here saves ~0.5 microsecond of real time - not worth it.
195 #if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
198 /* Handle all names < 2 chars long early */
200 return -1; /* "" is not a valid applet name */
201 if (name[1] == '\0') {
203 return -1; /* 1-char name is not valid */
205 return -1; /* 1-char name which isn't "[" is not valid */
206 /* applet "[" is always applet #0: */
213 #if KNOWN_APPNAME_OFFSETS <= 0
216 max = NUM_APPLETS * KNOWN_APPNAME_OFFSETS;
217 for (j = ARRAY_SIZE(applet_nameofs)-1; j >= 0; j--) {
218 const char *pp = applet_names + applet_nameofs[j];
219 if (strcmp(name, pp) >= 0) {
220 //bb_error_msg("name:'%s' >= pp:'%s'", name, pp);
222 i = max - NUM_APPLETS;
227 max /= (unsigned)KNOWN_APPNAME_OFFSETS;
228 i /= (unsigned)KNOWN_APPNAME_OFFSETS;
229 //bb_error_msg("name:'%s' starting from:'%s' i:%u max:%u", name, p, i, max);
232 /* Open-coded linear search without strcmp/strlen calls for speed */
234 #if 0 /*BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN*/
235 /* skip "[\0" name, it's surely not it */
236 if (ENABLE_TEST && LONE_CHAR(p, '['))
238 /* All remaining applet names in p[] are at least 2 chars long */
239 /* name[] is also at least 2 chars long */
241 n32 = (name[0] << 0) | (name[1] << 8) | (name[2] << 16);
246 /* Quickly check match of the first 3 bytes */
247 move_from_unaligned32(p32, p);
249 if ((p32 & 0x00ffffff) != n32) {
250 /* Most likely case: 3 first bytes do not match */
252 if ((p32 & 0x00ff0000) == '\0')
253 continue; // p[2] was NUL
255 if ((p32 & 0xff000000) == '\0')
256 continue; // p[3] was NUL
257 /* p[0..3] aren't matching and none is NUL, check the rest */
263 /* Unlikely branch: first 3 bytes ([0..2]) match */
264 if ((p32 & 0x00ff0000) == '\0') {
265 /* name is 2-byte long, it is full match */
266 //bb_error_msg("found:'%s' i:%u", name, i);
269 /* Check remaining bytes [3..NUL] */
272 while (ch == name[j]) {
274 //bb_error_msg("found:'%s' i:%u", name, i);
280 /* Not a match. Skip it, including NUL */
291 /* Do we see "name\0" in applet_names[p] position? */
292 while ((ch = *p) == name[j]) {
294 //bb_error_msg("found:'%s' i:%u", name, i);
301 * p => 1st non-matching char in applet_names[],
302 * skip to and including NUL.
314 void lbb_prepare(const char *applet
315 IF_FEATURE_INDIVIDUAL(, char **argv))
316 MAIN_EXTERNALLY_VISIBLE;
317 void lbb_prepare(const char *applet
318 IF_FEATURE_INDIVIDUAL(, char **argv))
321 (*(int **)&bb_errno) = __errno_location();
324 applet_name = applet;
326 if (ENABLE_LOCALE_SUPPORT)
327 setlocale(LC_ALL, "");
329 #if ENABLE_FEATURE_INDIVIDUAL
330 /* Redundant for busybox (run_applet_and_exit covers that case)
331 * but needed for "individual applet" mode */
334 && strcmp(argv[1], "--help") == 0
335 && !is_prefixed_with(applet, "busybox")
337 /* Special case. POSIX says "test --help"
338 * should be no different from e.g. "test --foo". */
339 if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
345 /* The code below can well be in applets/applets.c, as it is used only
346 * for busybox binary, not "individual" binaries.
347 * However, keeping it here and linking it into libbusybox.so
348 * (together with remaining tiny applets/applets.o)
349 * makes it possible to avoid --whole-archive at link time.
350 * This makes (shared busybox) + libbusybox smaller.
351 * (--gc-sections would be even better....)
354 const char *applet_name;
360 /* If not built as a single-applet executable... */
361 #if !defined(SINGLE_APPLET_MAIN)
363 IF_FEATURE_SUID(static uid_t ruid;) /* real uid */
365 # if ENABLE_FEATURE_SUID_CONFIG
367 static struct suid_config_t {
368 /* next ptr must be first: this struct needs to be llist-compatible */
369 struct suid_config_t *m_next;
370 struct bb_uidgid_t m_ugid;
375 static bool suid_cfg_readable;
377 /* libbb candidate */
378 static char *get_trimmed_slice(char *s, char *e)
380 /* First, consider the value at e to be nul and back up until we
381 * reach a non-space char. Set the char after that (possibly at
382 * the original e) to nul. */
390 /* Next, advance past all leading space and return a ptr to the
391 * first non-space char; possibly the terminating nul. */
392 return skip_whitespace(s);
395 static void parse_config_file(void)
397 /* Don't depend on the tools to combine strings. */
398 static const char config_file[] ALIGN1 = "/etc/busybox.conf";
400 struct suid_config_t *sct_head;
409 if (ruid == 0) /* run by root - don't need to even read config file */
412 if ((stat(config_file, &st) != 0) /* No config file? */
413 || !S_ISREG(st.st_mode) /* Not a regular file? */
414 || (st.st_uid != 0) /* Not owned by root? */
415 || (st.st_mode & (S_IWGRP | S_IWOTH)) /* Writable by non-root? */
416 || !(f = fopen_for_read(config_file)) /* Cannot open? */
421 suid_cfg_readable = 1;
429 if (!fgets(buffer, sizeof(buffer), f)) { /* Are we done? */
431 //if (ferror(f)) { /* Make sure it wasn't a read error. */
432 // errmsg = "reading";
436 suid_config = sct_head; /* Success, so set the pointer. */
441 lc++; /* Got a (partial) line. */
443 /* If a line is too long for our buffer, we consider it an error.
444 * The following test does mistreat one corner case though.
445 * If the final line of the file does not end with a newline and
446 * yet exactly fills the buffer, it will be treated as too long
447 * even though there isn't really a problem. But it isn't really
448 * worth adding code to deal with such an unlikely situation, and
449 * we do err on the side of caution. Besides, the line would be
450 * too long if it did end with a newline. */
451 if (!strchr(s, '\n') && !feof(f)) {
452 errmsg = "line too long";
456 /* Trim leading and trailing whitespace, ignoring comments, and
457 * check if the resulting string is empty. */
458 s = get_trimmed_slice(s, strchrnul(s, '#'));
463 /* Check for a section header. */
466 /* Unlike the old code, we ignore leading and trailing
467 * whitespace for the section name. We also require that
468 * there are no stray characters after the closing bracket. */
469 char *e = strchr(s, ']');
470 if (!e /* Missing right bracket? */
471 || e[1] /* Trailing characters? */
472 || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
474 errmsg = "section header";
477 /* Right now we only have one section so just check it.
478 * If more sections are added in the future, please don't
479 * resort to cascading ifs with multiple strcasecmp calls.
480 * That kind of bloated code is all too common. A loop
481 * and a string table would be a better choice unless the
482 * number of sections is very small. */
483 if (strcasecmp(s, "SUID") == 0) {
487 section = -1; /* Unknown section so set to skip. */
491 /* Process sections. */
493 if (section == 1) { /* SUID */
494 /* Since we trimmed leading and trailing space above, we're
495 * now looking for strings of the form
496 * <key>[::space::]*=[::space::]*<value>
497 * where both key and value could contain inner whitespace. */
499 /* First get the key (an applet name in our case). */
500 char *e = strchr(s, '=');
502 s = get_trimmed_slice(s, e);
504 if (!e || !*s) { /* Missing '=' or empty key. */
509 /* Ok, we have an applet name. Process the rhs if this
510 * applet is currently built in and ignore it otherwise.
511 * Note: this can hide config file bugs which only pop
512 * up when the busybox configuration is changed. */
513 applet_no = find_applet_by_name(s);
514 if (applet_no >= 0) {
516 struct suid_config_t *sct;
518 /* Note: We currently don't check for duplicates!
519 * The last config line for each applet will be the
520 * one used since we insert at the head of the list.
521 * I suppose this could be considered a feature. */
522 sct = xzalloc(sizeof(*sct));
523 sct->m_applet = applet_no;
525 sct->m_next = sct_head;
528 /* Get the specified mode. */
530 e = skip_whitespace(e+1);
532 for (i = 0; i < 3; i++) {
533 /* There are 4 chars for each of user/group/other.
534 * "x-xx" instead of "x-" are to make
535 * "idx > 3" check catch invalid chars.
537 static const char mode_chars[] ALIGN1 = "Ssx-" "Ssx-" "x-xx";
538 static const unsigned short mode_mask[] ALIGN2 = {
539 S_ISUID, S_ISUID|S_IXUSR, S_IXUSR, 0, /* Ssx- */
540 S_ISGID, S_ISGID|S_IXGRP, S_IXGRP, 0, /* Ssx- */
543 const char *q = strchrnul(mode_chars + 4*i, *e);
544 unsigned idx = q - (mode_chars + 4*i);
549 sct->m_mode |= mode_mask[q - mode_chars];
553 /* Now get the user/group info. */
555 s = skip_whitespace(e);
556 /* Default is 0.0, else parse USER.GROUP: */
558 /* We require whitespace between mode and USER.GROUP */
559 if ((s == e) || !(e = strchr(s, '.'))) {
563 *e = ':'; /* get_uidgid needs USER:GROUP syntax */
564 if (get_uidgid(&sct->m_ugid, s) == 0) {
565 errmsg = "unknown user/group";
573 /* Unknown sections are ignored. */
575 /* Encountering configuration lines prior to seeing a
576 * section header is treated as an error. This is how
577 * the old code worked, but it may not be desirable.
578 * We may want to simply ignore such lines in case they
579 * are used in some future version of busybox. */
581 errmsg = "keyword outside section";
588 bb_error_msg("parse error in %s, line %u: %s", config_file, lc, errmsg);
590 /* Release any allocated memory before returning. */
591 llist_free((llist_t*)sct_head, NULL);
594 static inline void parse_config_file(void)
596 IF_FEATURE_SUID(ruid = getuid();)
598 # endif /* FEATURE_SUID_CONFIG */
601 # if ENABLE_FEATURE_SUID && NUM_APPLETS > 0
602 # if ENABLE_FEATURE_SUID_CONFIG
603 /* check if u is member of group g */
604 static int ingroup(uid_t u, gid_t g)
606 struct group *grp = getgrgid(g);
609 for (mem = grp->gr_mem; *mem; mem++) {
610 struct passwd *pwd = getpwnam(*mem);
611 if (pwd && (pwd->pw_uid == u))
619 static void check_suid(int applet_no)
621 gid_t rgid; /* real gid */
623 if (ruid == 0) /* set by parse_config_file() */
624 return; /* run by root - no need to check more */
627 # if ENABLE_FEATURE_SUID_CONFIG
628 if (suid_cfg_readable) {
630 struct suid_config_t *sct;
633 for (sct = suid_config; sct; sct = sct->m_next) {
634 if (sct->m_applet == applet_no)
637 goto check_need_suid;
639 /* Is this user allowed to run this applet? */
641 if (sct->m_ugid.uid == ruid)
644 else if ((sct->m_ugid.gid == rgid) || ingroup(ruid, sct->m_ugid.gid))
645 /* same group / in group */
647 if (!(m & S_IXOTH)) /* is x bit not set? */
648 bb_error_msg_and_die("you have no permission to run this applet");
650 /* We set effective AND saved ids. If saved-id is not set
651 * like we do below, seteuid(0) can still later succeed! */
653 /* Are we directed to change gid
654 * (APPLET = *s* USER.GROUP or APPLET = *S* USER.GROUP)?
656 if (sct->m_mode & S_ISGID)
657 rgid = sct->m_ugid.gid;
658 /* else: we will set egid = rgid, thus dropping sgid effect */
659 if (setresgid(-1, rgid, rgid))
660 bb_perror_msg_and_die("setresgid");
662 /* Are we directed to change uid
663 * (APPLET = s** USER.GROUP or APPLET = S** USER.GROUP)?
666 if (sct->m_mode & S_ISUID)
667 uid = sct->m_ugid.uid;
668 /* else: we will set euid = ruid, thus dropping suid effect */
669 if (setresuid(-1, uid, uid))
670 bb_perror_msg_and_die("setresuid");
674 # if !ENABLE_FEATURE_SUID_CONFIG_QUIET
676 static bool onetime = 0;
680 bb_error_msg("using fallback suid method");
686 if (APPLET_SUID(applet_no) == BB_SUID_REQUIRE) {
687 /* Real uid is not 0. If euid isn't 0 too, suid bit
688 * is most probably not set on our executable */
690 bb_error_msg_and_die("must be suid to work properly");
691 } else if (APPLET_SUID(applet_no) == BB_SUID_DROP) {
693 * Drop all privileges.
695 * Don't check for errors: in normal use, they are impossible,
696 * and in special cases, exiting is harmful. Example:
697 * 'unshare --user' when user's shell is also from busybox.
699 * 'unshare --user' creates a new user namespace without any
700 * uid mappings. Thus, busybox binary is setuid nobody:nogroup
701 * within the namespace, as that is the only user. However,
702 * since no uids are mapped, calls to setgid/setuid
703 * fail (even though they would do nothing).
708 # if ENABLE_FEATURE_SUID_CONFIG
710 llist_free((llist_t*)suid_config, NULL);
714 # define check_suid(x) ((void)0)
715 # endif /* FEATURE_SUID */
718 # if ENABLE_FEATURE_INSTALLER
719 static const char usr_bin [] ALIGN1 = "/usr/bin/";
720 static const char usr_sbin[] ALIGN1 = "/usr/sbin/";
721 static const char *const install_dir[] = {
722 &usr_bin [8], /* "/" */
723 &usr_bin [4], /* "/bin/" */
724 &usr_sbin[4] /* "/sbin/" */
725 # if !ENABLE_INSTALL_NO_USR
731 /* create (sym)links for each applet */
732 static void install_links(const char *busybox, int use_symbolic_links,
733 char *custom_install_dir)
736 * this should be consistent w/ the enum,
737 * busybox.h::bb_install_loc_t, or else... */
738 int (*lf)(const char *, const char *);
740 const char *appname = applet_names;
745 if (use_symbolic_links)
748 for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
749 fpc = concat_path_file(
750 custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
752 // debug: bb_error_msg("%slinking %s to busybox",
753 // use_symbolic_links ? "sym" : "", fpc);
754 rc = lf(busybox, fpc);
755 if (rc != 0 && errno != EEXIST) {
756 bb_simple_perror_msg(fpc);
759 while (*appname++ != '\0')
763 # elif ENABLE_BUSYBOX
764 static void install_links(const char *busybox UNUSED_PARAM,
765 int use_symbolic_links UNUSED_PARAM,
766 char *custom_install_dir UNUSED_PARAM)
771 static void run_applet_and_exit(const char *name, char **argv) NORETURN;
774 # if ENABLE_FEATURE_SH_STANDALONE && ENABLE_FEATURE_TAB_COMPLETION
776 * Insert "busybox" into applet table as well.
777 * This makes standalone shell tab-complete this name too.
778 * (Otherwise having "busybox" in applet table is not necessary,
779 * there is other code which routes "busyboxANY_SUFFIX" name
780 * to busybox_main()).
782 //usage:#define busybox_trivial_usage NOUSAGE_STR
783 //usage:#define busybox_full_usage ""
784 //applet:IF_BUSYBOX(IF_FEATURE_SH_STANDALONE(IF_FEATURE_TAB_COMPLETION(APPLET(busybox, BB_DIR_BIN, BB_SUID_MAYBE))))
785 int busybox_main(int argc, char *argv[]) MAIN_EXTERNALLY_VISIBLE;
787 # define busybox_main(argc,argv) busybox_main(argv)
790 int busybox_main(int argc UNUSED_PARAM, char **argv)
793 /* Called without arguments */
796 unsigned output_width;
798 output_width = get_terminal_width(2);
801 full_write2_str(bb_banner); /* reuse const string */
802 full_write2_str(" multi-call binary.\n"); /* reuse */
804 "BusyBox is copyrighted by many authors between 1998-2015.\n"
805 "Licensed under GPLv2. See source distribution for detailed\n"
806 "copyright notices.\n"
808 "Usage: busybox [function [arguments]...]\n"
809 " or: busybox --list"IF_FEATURE_INSTALLER("[-full]")"\n"
810 IF_FEATURE_INSTALLER(
811 " or: busybox --install [-s] [DIR]\n"
813 " or: function [arguments]...\n"
815 IF_NOT_FEATURE_SH_STANDALONE(
816 "\tBusyBox is a multi-call binary that combines many common Unix\n"
817 "\tutilities into a single executable. Most people will create a\n"
818 "\tlink to busybox for each function they wish to use and BusyBox\n"
819 "\twill act like whatever it was invoked as.\n"
821 IF_FEATURE_SH_STANDALONE(
822 "\tBusyBox is a multi-call binary that combines many common Unix\n"
823 "\tutilities into a single executable. The shell in this build\n"
824 "\tis configured to run built-in utilities without $PATH search.\n"
825 "\tYou don't need to install a link to busybox for each utility.\n"
826 "\tTo run external program, use full path (/sbin/ip instead of ip).\n"
829 "Currently defined functions:\n"
833 /* prevent last comma to be in the very last pos */
836 int len2 = strlen(a) + 2;
837 if (col >= (int)output_width - len2) {
838 full_write2_str(",\n");
843 full_write2_str("\t");
845 full_write2_str(", ");
851 full_write2_str("\n");
855 if (is_prefixed_with(argv[1], "--list")) {
857 const char *a = applet_names;
860 # if ENABLE_FEATURE_INSTALLER
861 if (argv[1][6]) /* --list-full? */
862 full_write2_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
865 full_write2_str("\n");
873 if (ENABLE_FEATURE_INSTALLER && strcmp(argv[1], "--install") == 0) {
874 int use_symbolic_links;
877 busybox = xmalloc_readlink(bb_busybox_exec_path);
879 /* bb_busybox_exec_path is usually "/proc/self/exe".
880 * In chroot, readlink("/proc/self/exe") usually fails.
881 * In such case, better use argv[0] as symlink target
882 * if it is a full path name.
884 if (argv[0][0] != '/')
885 bb_error_msg_and_die("'%s' is not an absolute path", argv[0]);
888 /* busybox --install [-s] [DIR]:
890 * DIR: directory to install links to
892 use_symbolic_links = (argv[2] && strcmp(argv[2], "-s") == 0 && ++argv);
893 install_links(busybox, use_symbolic_links, argv[2]);
897 if (strcmp(argv[1], "--help") == 0) {
898 /* "busybox --help [<applet>]" */
901 /* convert to "<applet> --help" */
905 /* "busybox <applet> arg1 arg2 ..." */
908 /* We support "busybox /a/path/to/applet args..." too. Allows for
909 * "#!/bin/busybox"-style wrappers */
910 applet_name = bb_get_last_path_component_nostrip(argv[0]);
911 run_applet_and_exit(applet_name, argv);
916 void FAST_FUNC run_applet_no_and_exit(int applet_no, const char *name, char **argv)
918 int argc = string_array_len(argv);
921 * We do not use argv[0]: do not want to repeat massaging of
922 * "-/sbin/halt" -> "halt", for example.
926 /* Special case. POSIX says "test --help"
927 * should be no different from e.g. "test --foo".
928 * Thus for "test", we skip --help check.
929 * "true" and "false" are also special.
932 # if defined APPLET_NO_test
933 && applet_no != APPLET_NO_test
935 # if defined APPLET_NO_true
936 && applet_no != APPLET_NO_true
938 # if defined APPLET_NO_false
939 && applet_no != APPLET_NO_false
942 if (argc == 2 && strcmp(argv[1], "--help") == 0) {
943 /* Make "foo --help" exit with 0: */
944 xfunc_error_retval = 0;
948 if (ENABLE_FEATURE_SUID)
949 check_suid(applet_no);
950 xfunc_error_retval = applet_main[applet_no](argc, argv);
951 /* Note: applet_main() may also not return (die on a xfunc or such) */
954 # endif /* NUM_APPLETS > 0 */
956 # if ENABLE_BUSYBOX || NUM_APPLETS > 0
957 static NORETURN void run_applet_and_exit(const char *name, char **argv)
960 if (is_prefixed_with(name, "busybox"))
961 exit(busybox_main(/*unused:*/ 0, argv));
964 /* find_applet_by_name() search is more expensive, so goes second */
966 int applet = find_applet_by_name(name);
968 run_applet_no_and_exit(applet, name, argv);
972 /*bb_error_msg_and_die("applet not found"); - links in printf */
973 full_write2_str(applet_name);
974 full_write2_str(": applet not found\n");
975 /* POSIX: "If a command is not found, the exit status shall be 127" */
980 #endif /* !defined(SINGLE_APPLET_MAIN) */
983 #if ENABLE_BUILD_LIBBUSYBOX
984 int lbb_main(char **argv)
986 int main(int argc UNUSED_PARAM, char **argv)
990 /* TODO: find a use for a block of memory between end of .bss
991 * and end of page. For example, I'm getting "_end:0x812e698 2408 bytes"
992 * - more than 2k of wasted memory (in this particular build)
993 * *per each running process*!
994 * (If your linker does not generate "_end" name, weak attribute
995 * makes &_end == NULL, end_len == 0 here.)
997 extern char _end[] __attribute__((weak));
998 unsigned end_len = (-(int)_end) & 0xfff;
999 printf("_end:%p %u bytes\n", &_end, end_len);
1002 /* Tweak malloc for reduced memory consumption */
1003 #ifdef M_TRIM_THRESHOLD
1004 /* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
1005 * to keep before releasing to the OS
1006 * Default is way too big: 256k
1008 mallopt(M_TRIM_THRESHOLD, 8 * 1024);
1010 #ifdef M_MMAP_THRESHOLD
1011 /* M_MMAP_THRESHOLD is the request size threshold for using mmap()
1012 * Default is too big: 256k
1014 mallopt(M_MMAP_THRESHOLD, 32 * 1024 - 256);
1016 #if 0 /*def M_TOP_PAD*/
1017 /* When the program break is increased, then M_TOP_PAD bytes are added
1018 * to the sbrk(2) request. When the heap is trimmed because of free(3),
1019 * this much free space is preserved at the top of the heap.
1020 * glibc default seems to be way too big: 128k, but need to verify.
1022 mallopt(M_TOP_PAD, 8 * 1024);
1026 /* NOMMU re-exec trick sets high-order bit in first byte of name */
1027 if (argv[0][0] & 0x80) {
1033 #if defined(SINGLE_APPLET_MAIN)
1035 /* Only one applet is selected in .config */
1036 if (argv[1] && is_prefixed_with(argv[0], "busybox")) {
1037 /* "busybox <applet> <params>" should still work as expected */
1040 /* applet_names in this case is just "applet\0\0" */
1041 lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
1042 # if ENABLE_BUILD_LIBBUSYBOX
1043 return SINGLE_APPLET_MAIN(string_array_len(argv), argv);
1045 return SINGLE_APPLET_MAIN(argc, argv);
1048 #elif !ENABLE_BUSYBOX && NUM_APPLETS == 0
1050 full_write2_str(bb_basename(argv[0]));
1051 full_write2_str(": no applets enabled\n");
1056 lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
1057 # if !ENABLE_BUSYBOX
1058 if (argv[1] && is_prefixed_with(bb_basename(argv[0]), "busybox"))
1061 applet_name = argv[0];
1062 if (applet_name[0] == '-')
1064 applet_name = bb_basename(applet_name);
1066 /* If we are a result of execv("/proc/self/exe"), fix ugly comm of "exe" */
1067 if (ENABLE_FEATURE_SH_STANDALONE
1068 || ENABLE_FEATURE_PREFER_APPLETS
1071 if (NUM_APPLETS > 1)
1072 set_task_comm(applet_name);
1075 parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
1076 run_applet_and_exit(applet_name, argv);