Magellan Linux

Contents of /trunk/mkinitrd-magellan/busybox/libbb/appletlib.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 984 - (show annotations) (download)
Sun May 30 11:32:42 2010 UTC (13 years, 11 months ago) by niro
File MIME type: text/plain
File size: 21930 byte(s)
-updated to busybox-1.16.1 and enabled blkid/uuid support in default config
1 /* vi: set sw=4 ts=4: */
2 /*
3 * Utility routines.
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.
8 *
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 the GPL.
11 *
12 * Licensed under GPLv2 or later, see file License in this tarball for details.
13 */
14
15 /* We are trying to not use printf, this benefits the case when selected
16 * applets are really simple. Example:
17 *
18 * $ ./busybox
19 * ...
20 * Currently defined functions:
21 * basename, false, true
22 *
23 * $ size busybox
24 * text data bss dec hex filename
25 * 4473 52 72 4597 11f5 busybox
26 *
27 * FEATURE_INSTALLER or FEATURE_SUID will still link printf routines in. :(
28 */
29
30 #include "busybox.h"
31 #include <assert.h>
32 #include <malloc.h>
33 #include <sys/user.h> /* PAGE_SIZE */
34
35
36 /* Declare <applet>_main() */
37 #define PROTOTYPES
38 #include "applets.h"
39 #undef PROTOTYPES
40
41 #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
42 /* Define usage_messages[] */
43 static const char usage_messages[] ALIGN1 = ""
44 #define MAKE_USAGE
45 #include "usage.h"
46 #include "applets.h"
47 ;
48 #undef MAKE_USAGE
49 #else
50 #define usage_messages 0
51 #endif /* SHOW_USAGE */
52
53
54 /* Include generated applet names, pointers to <applet>_main, etc */
55 #include "applet_tables.h"
56 /* ...and if applet_tables generator says we have only one applet... */
57 #ifdef SINGLE_APPLET_MAIN
58 #undef ENABLE_FEATURE_INDIVIDUAL
59 #define ENABLE_FEATURE_INDIVIDUAL 1
60 #undef IF_FEATURE_INDIVIDUAL
61 #define IF_FEATURE_INDIVIDUAL(...) __VA_ARGS__
62 #endif
63
64
65 #if ENABLE_FEATURE_COMPRESS_USAGE
66
67 #include "usage_compressed.h"
68 #include "unarchive.h"
69
70 static const char *unpack_usage_messages(void)
71 {
72 char *outbuf = NULL;
73 bunzip_data *bd;
74 int i;
75
76 i = start_bunzip(&bd,
77 /* src_fd: */ -1,
78 /* inbuf: */ (void *)packed_usage,
79 /* len: */ sizeof(packed_usage));
80 /* read_bunzip can longjmp to start_bunzip, and ultimately
81 * end up here with i != 0 on read data errors! Not trivial */
82 if (!i) {
83 /* Cannot use xmalloc: will leak bd in NOFORK case! */
84 outbuf = malloc_or_warn(SIZEOF_usage_messages);
85 if (outbuf)
86 read_bunzip(bd, outbuf, SIZEOF_usage_messages);
87 }
88 dealloc_bunzip(bd);
89 return outbuf;
90 }
91 #define dealloc_usage_messages(s) free(s)
92
93 #else
94
95 #define unpack_usage_messages() usage_messages
96 #define dealloc_usage_messages(s) ((void)(s))
97
98 #endif /* FEATURE_COMPRESS_USAGE */
99
100
101 static void full_write2_str(const char *str)
102 {
103 xwrite_str(STDERR_FILENO, str);
104 }
105
106 void FAST_FUNC bb_show_usage(void)
107 {
108 if (ENABLE_SHOW_USAGE) {
109 #ifdef SINGLE_APPLET_STR
110 /* Imagine that this applet is "true". Dont suck in printf! */
111 const char *p;
112 const char *usage_string = p = unpack_usage_messages();
113
114 if (*p == '\b') {
115 full_write2_str("No help available.\n\n");
116 } else {
117 full_write2_str("Usage: "SINGLE_APPLET_STR" ");
118 full_write2_str(p);
119 full_write2_str("\n\n");
120 }
121 if (ENABLE_FEATURE_CLEAN_UP)
122 dealloc_usage_messages((char*)usage_string);
123 #else
124 const char *p;
125 const char *usage_string = p = unpack_usage_messages();
126 int ap = find_applet_by_name(applet_name);
127
128 if (ap < 0) /* never happens, paranoia */
129 xfunc_die();
130 while (ap) {
131 while (*p++) continue;
132 ap--;
133 }
134 full_write2_str(bb_banner);
135 full_write2_str(" multi-call binary.\n");
136 if (*p == '\b')
137 full_write2_str("\nNo help available.\n\n");
138 else {
139 full_write2_str("\nUsage: ");
140 full_write2_str(applet_name);
141 full_write2_str(" ");
142 full_write2_str(p);
143 full_write2_str("\n\n");
144 }
145 if (ENABLE_FEATURE_CLEAN_UP)
146 dealloc_usage_messages((char*)usage_string);
147 #endif
148 }
149 xfunc_die();
150 }
151
152 #if NUM_APPLETS > 8
153 /* NB: any char pointer will work as well, not necessarily applet_names */
154 static int applet_name_compare(const void *name, const void *v)
155 {
156 int i = (const char *)v - applet_names;
157 return strcmp(name, APPLET_NAME(i));
158 }
159 #endif
160 int FAST_FUNC find_applet_by_name(const char *name)
161 {
162 #if NUM_APPLETS > 8
163 /* Do a binary search to find the applet entry given the name. */
164 const char *p;
165 p = bsearch(name, applet_names, ARRAY_SIZE(applet_main), 1, applet_name_compare);
166 if (!p)
167 return -1;
168 return p - applet_names;
169 #else
170 /* A version which does not pull in bsearch */
171 int i = 0;
172 const char *p = applet_names;
173 while (i < NUM_APPLETS) {
174 if (strcmp(name, p) == 0)
175 return i;
176 p += strlen(p) + 1;
177 i++;
178 }
179 return -1;
180 #endif
181 }
182
183
184 void lbb_prepare(const char *applet
185 IF_FEATURE_INDIVIDUAL(, char **argv))
186 MAIN_EXTERNALLY_VISIBLE;
187 void lbb_prepare(const char *applet
188 IF_FEATURE_INDIVIDUAL(, char **argv))
189 {
190 #ifdef __GLIBC__
191 (*(int **)&bb_errno) = __errno_location();
192 barrier();
193 #endif
194 applet_name = applet;
195
196 /* Set locale for everybody except 'init' */
197 if (ENABLE_LOCALE_SUPPORT && getpid() != 1)
198 setlocale(LC_ALL, "");
199
200 #if ENABLE_FEATURE_INDIVIDUAL
201 /* Redundant for busybox (run_applet_and_exit covers that case)
202 * but needed for "individual applet" mode */
203 if (argv[1] && !argv[2] && strcmp(argv[1], "--help") == 0) {
204 /* Special case. POSIX says "test --help"
205 * should be no different from e.g. "test --foo". */
206 if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
207 bb_show_usage();
208 }
209 #endif
210 }
211
212 /* The code below can well be in applets/applets.c, as it is used only
213 * for busybox binary, not "individual" binaries.
214 * However, keeping it here and linking it into libbusybox.so
215 * (together with remaining tiny applets/applets.o)
216 * makes it possible to avoid --whole-archive at link time.
217 * This makes (shared busybox) + libbusybox smaller.
218 * (--gc-sections would be even better....)
219 */
220
221 const char *applet_name;
222 #if !BB_MMU
223 bool re_execed;
224 #endif
225
226
227 /* If not built as a single-applet executable... */
228 #if !defined(SINGLE_APPLET_MAIN)
229
230 IF_FEATURE_SUID(static uid_t ruid;) /* real uid */
231
232 #if ENABLE_FEATURE_SUID_CONFIG
233
234 /* applets[] is const, so we have to define this "override" structure */
235 static struct BB_suid_config {
236 int m_applet;
237 uid_t m_uid;
238 gid_t m_gid;
239 mode_t m_mode;
240 struct BB_suid_config *m_next;
241 } *suid_config;
242
243 static bool suid_cfg_readable;
244
245 /* check if u is member of group g */
246 static int ingroup(uid_t u, gid_t g)
247 {
248 struct group *grp = getgrgid(g);
249
250 if (grp) {
251 char **mem;
252
253 for (mem = grp->gr_mem; *mem; mem++) {
254 struct passwd *pwd = getpwnam(*mem);
255
256 if (pwd && (pwd->pw_uid == u))
257 return 1;
258 }
259 }
260 return 0;
261 }
262
263 /* This should probably be a libbb routine. In that case,
264 * I'd probably rename it to something like bb_trimmed_slice.
265 */
266 static char *get_trimmed_slice(char *s, char *e)
267 {
268 /* First, consider the value at e to be nul and back up until we
269 * reach a non-space char. Set the char after that (possibly at
270 * the original e) to nul. */
271 while (e-- > s) {
272 if (!isspace(*e)) {
273 break;
274 }
275 }
276 e[1] = '\0';
277
278 /* Next, advance past all leading space and return a ptr to the
279 * first non-space char; possibly the terminating nul. */
280 return skip_whitespace(s);
281 }
282
283 /* Don't depend on the tools to combine strings. */
284 static const char config_file[] ALIGN1 = "/etc/busybox.conf";
285
286 /* We don't supply a value for the nul, so an index adjustment is
287 * necessary below. Also, we use unsigned short here to save some
288 * space even though these are really mode_t values. */
289 static const unsigned short mode_mask[] ALIGN2 = {
290 /* SST sst xxx --- */
291 S_ISUID, S_ISUID|S_IXUSR, S_IXUSR, 0, /* user */
292 S_ISGID, S_ISGID|S_IXGRP, S_IXGRP, 0, /* group */
293 0, S_IXOTH, S_IXOTH, 0 /* other */
294 };
295
296 #define parse_error(x) do { errmsg = x; goto pe_label; } while (0)
297
298 static void parse_config_file(void)
299 {
300 struct BB_suid_config *sct_head;
301 struct BB_suid_config *sct;
302 int applet_no;
303 FILE *f;
304 const char *errmsg;
305 char *s;
306 char *e;
307 int i;
308 unsigned lc;
309 smallint section;
310 char buffer[256];
311 struct stat st;
312
313 assert(!suid_config); /* Should be set to NULL by bss init. */
314
315 ruid = getuid();
316 if (ruid == 0) /* run by root - don't need to even read config file */
317 return;
318
319 if ((stat(config_file, &st) != 0) /* No config file? */
320 || !S_ISREG(st.st_mode) /* Not a regular file? */
321 || (st.st_uid != 0) /* Not owned by root? */
322 || (st.st_mode & (S_IWGRP | S_IWOTH)) /* Writable by non-root? */
323 || !(f = fopen_for_read(config_file)) /* Cannot open? */
324 ) {
325 return;
326 }
327
328 suid_cfg_readable = 1;
329 sct_head = NULL;
330 section = lc = 0;
331
332 while (1) {
333 s = buffer;
334
335 if (!fgets(s, sizeof(buffer), f)) { /* Are we done? */
336 // why?
337 if (ferror(f)) { /* Make sure it wasn't a read error. */
338 parse_error("reading");
339 }
340 fclose(f);
341 suid_config = sct_head; /* Success, so set the pointer. */
342 return;
343 }
344
345 lc++; /* Got a (partial) line. */
346
347 /* If a line is too long for our buffer, we consider it an error.
348 * The following test does mistreat one corner case though.
349 * If the final line of the file does not end with a newline and
350 * yet exactly fills the buffer, it will be treated as too long
351 * even though there isn't really a problem. But it isn't really
352 * worth adding code to deal with such an unlikely situation, and
353 * we do err on the side of caution. Besides, the line would be
354 * too long if it did end with a newline. */
355 if (!strchr(s, '\n') && !feof(f)) {
356 parse_error("line too long");
357 }
358
359 /* Trim leading and trailing whitespace, ignoring comments, and
360 * check if the resulting string is empty. */
361 s = get_trimmed_slice(s, strchrnul(s, '#'));
362 if (!*s) {
363 continue;
364 }
365
366 /* Check for a section header. */
367
368 if (*s == '[') {
369 /* Unlike the old code, we ignore leading and trailing
370 * whitespace for the section name. We also require that
371 * there are no stray characters after the closing bracket. */
372 e = strchr(s, ']');
373 if (!e /* Missing right bracket? */
374 || e[1] /* Trailing characters? */
375 || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
376 ) {
377 parse_error("section header");
378 }
379 /* Right now we only have one section so just check it.
380 * If more sections are added in the future, please don't
381 * resort to cascading ifs with multiple strcasecmp calls.
382 * That kind of bloated code is all too common. A loop
383 * and a string table would be a better choice unless the
384 * number of sections is very small. */
385 if (strcasecmp(s, "SUID") == 0) {
386 section = 1;
387 continue;
388 }
389 section = -1; /* Unknown section so set to skip. */
390 continue;
391 }
392
393 /* Process sections. */
394
395 if (section == 1) { /* SUID */
396 /* Since we trimmed leading and trailing space above, we're
397 * now looking for strings of the form
398 * <key>[::space::]*=[::space::]*<value>
399 * where both key and value could contain inner whitespace. */
400
401 /* First get the key (an applet name in our case). */
402 e = strchr(s, '=');
403 if (e) {
404 s = get_trimmed_slice(s, e);
405 }
406 if (!e || !*s) { /* Missing '=' or empty key. */
407 parse_error("keyword");
408 }
409
410 /* Ok, we have an applet name. Process the rhs if this
411 * applet is currently built in and ignore it otherwise.
412 * Note: this can hide config file bugs which only pop
413 * up when the busybox configuration is changed. */
414 applet_no = find_applet_by_name(s);
415 if (applet_no >= 0) {
416 /* Note: We currently don't check for duplicates!
417 * The last config line for each applet will be the
418 * one used since we insert at the head of the list.
419 * I suppose this could be considered a feature. */
420 sct = xmalloc(sizeof(struct BB_suid_config));
421 sct->m_applet = applet_no;
422 sct->m_mode = 0;
423 sct->m_next = sct_head;
424 sct_head = sct;
425
426 /* Get the specified mode. */
427
428 e = skip_whitespace(e+1);
429
430 for (i = 0; i < 3; i++) {
431 /* There are 4 chars + 1 nul for each of user/group/other. */
432 static const char mode_chars[] ALIGN1 = "Ssx-\0" "Ssx-\0" "Ttx-";
433
434 const char *q;
435 q = strchrnul(mode_chars + 5*i, *e++);
436 if (!*q) {
437 parse_error("mode");
438 }
439 /* Adjust by -i to account for nul. */
440 sct->m_mode |= mode_mask[(q - mode_chars) - i];
441 }
442
443 /* Now get the the user/group info. */
444
445 s = skip_whitespace(e);
446
447 /* Note: we require whitespace between the mode and the
448 * user/group info. */
449 if ((s == e) || !(e = strchr(s, '.'))) {
450 parse_error("<uid>.<gid>");
451 }
452 *e++ = '\0';
453
454 /* We can't use get_ug_id here since it would exit()
455 * if a uid or gid was not found. Oh well... */
456 sct->m_uid = bb_strtoul(s, NULL, 10);
457 if (errno) {
458 struct passwd *pwd = getpwnam(s);
459 if (!pwd) {
460 parse_error("user");
461 }
462 sct->m_uid = pwd->pw_uid;
463 }
464
465 sct->m_gid = bb_strtoul(e, NULL, 10);
466 if (errno) {
467 struct group *grp;
468 grp = getgrnam(e);
469 if (!grp) {
470 parse_error("group");
471 }
472 sct->m_gid = grp->gr_gid;
473 }
474 }
475 continue;
476 }
477
478 /* Unknown sections are ignored. */
479
480 /* Encountering configuration lines prior to seeing a
481 * section header is treated as an error. This is how
482 * the old code worked, but it may not be desirable.
483 * We may want to simply ignore such lines in case they
484 * are used in some future version of busybox. */
485 if (!section) {
486 parse_error("keyword outside section");
487 }
488
489 } /* while (1) */
490
491 pe_label:
492 fprintf(stderr, "Parse error in %s, line %d: %s\n",
493 config_file, lc, errmsg);
494
495 fclose(f);
496 /* Release any allocated memory before returning. */
497 while (sct_head) {
498 sct = sct_head->m_next;
499 free(sct_head);
500 sct_head = sct;
501 }
502 }
503 #else
504 static inline void parse_config_file(void)
505 {
506 IF_FEATURE_SUID(ruid = getuid();)
507 }
508 #endif /* FEATURE_SUID_CONFIG */
509
510
511 #if ENABLE_FEATURE_SUID
512 static void check_suid(int applet_no)
513 {
514 gid_t rgid; /* real gid */
515
516 if (ruid == 0) /* set by parse_config_file() */
517 return; /* run by root - no need to check more */
518 rgid = getgid();
519
520 #if ENABLE_FEATURE_SUID_CONFIG
521 if (suid_cfg_readable) {
522 uid_t uid;
523 struct BB_suid_config *sct;
524 mode_t m;
525
526 for (sct = suid_config; sct; sct = sct->m_next) {
527 if (sct->m_applet == applet_no)
528 goto found;
529 }
530 goto check_need_suid;
531 found:
532 m = sct->m_mode;
533 if (sct->m_uid == ruid)
534 /* same uid */
535 m >>= 6;
536 else if ((sct->m_gid == rgid) || ingroup(ruid, sct->m_gid))
537 /* same group / in group */
538 m >>= 3;
539
540 if (!(m & S_IXOTH)) /* is x bit not set ? */
541 bb_error_msg_and_die("you have no permission to run this applet!");
542
543 /* _both_ sgid and group_exec have to be set for setegid */
544 if ((sct->m_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP))
545 rgid = sct->m_gid;
546 /* else (no setegid) we will set egid = rgid */
547
548 /* We set effective AND saved ids. If saved-id is not set
549 * like we do below, seteiud(0) can still later succeed! */
550 if (setresgid(-1, rgid, rgid))
551 bb_perror_msg_and_die("setresgid");
552
553 /* do we have to set effective uid? */
554 uid = ruid;
555 if (sct->m_mode & S_ISUID)
556 uid = sct->m_uid;
557 /* else (no seteuid) we will set euid = ruid */
558
559 if (setresuid(-1, uid, uid))
560 bb_perror_msg_and_die("setresuid");
561 return;
562 }
563 #if !ENABLE_FEATURE_SUID_CONFIG_QUIET
564 {
565 static bool onetime = 0;
566
567 if (!onetime) {
568 onetime = 1;
569 fprintf(stderr, "Using fallback suid method\n");
570 }
571 }
572 #endif
573 check_need_suid:
574 #endif
575 if (APPLET_SUID(applet_no) == _BB_SUID_REQUIRE) {
576 /* Real uid is not 0. If euid isn't 0 too, suid bit
577 * is most probably not set on our executable */
578 if (geteuid())
579 bb_error_msg_and_die("must be suid to work properly");
580 } else if (APPLET_SUID(applet_no) == _BB_SUID_DROP) {
581 xsetgid(rgid); /* drop all privileges */
582 xsetuid(ruid);
583 }
584 }
585 #else
586 #define check_suid(x) ((void)0)
587 #endif /* FEATURE_SUID */
588
589
590 #if ENABLE_FEATURE_INSTALLER
591 /* create (sym)links for each applet */
592 static void install_links(const char *busybox, int use_symbolic_links,
593 char *custom_install_dir)
594 {
595 /* directory table
596 * this should be consistent w/ the enum,
597 * busybox.h::bb_install_loc_t, or else... */
598 static const char usr_bin [] ALIGN1 = "/usr/bin";
599 static const char usr_sbin[] ALIGN1 = "/usr/sbin";
600 static const char *const install_dir[] = {
601 &usr_bin [8], /* "", equivalent to "/" for concat_path_file() */
602 &usr_bin [4], /* "/bin" */
603 &usr_sbin[4], /* "/sbin" */
604 usr_bin,
605 usr_sbin
606 };
607
608 int (*lf)(const char *, const char *);
609 char *fpc;
610 unsigned i;
611 int rc;
612
613 lf = link;
614 if (use_symbolic_links)
615 lf = symlink;
616
617 for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
618 fpc = concat_path_file(
619 custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
620 APPLET_NAME(i));
621 // debug: bb_error_msg("%slinking %s to busybox",
622 // use_symbolic_links ? "sym" : "", fpc);
623 rc = lf(busybox, fpc);
624 if (rc != 0 && errno != EEXIST) {
625 bb_simple_perror_msg(fpc);
626 }
627 free(fpc);
628 }
629 }
630 #else
631 #define install_links(x,y,z) ((void)0)
632 #endif /* FEATURE_INSTALLER */
633
634 /* If we were called as "busybox..." */
635 static int busybox_main(char **argv)
636 {
637 if (!argv[1]) {
638 /* Called without arguments */
639 const char *a;
640 int col;
641 unsigned output_width;
642 help:
643 output_width = 80;
644 if (ENABLE_FEATURE_AUTOWIDTH) {
645 /* Obtain the terminal width */
646 get_terminal_width_height(0, &output_width, NULL);
647 }
648
649 dup2(1, 2);
650 full_write2_str(bb_banner); /* reuse const string */
651 full_write2_str(" multi-call binary.\n"); /* reuse */
652 full_write2_str(
653 "Copyright (C) 1998-2009 Erik Andersen, Rob Landley, Denys Vlasenko\n"
654 "and others. Licensed under GPLv2.\n"
655 "See source distribution for full notice.\n"
656 "\n"
657 "Usage: busybox [function] [arguments]...\n"
658 " or: function [arguments]...\n"
659 "\n"
660 "\tBusyBox is a multi-call binary that combines many common Unix\n"
661 "\tutilities into a single executable. Most people will create a\n"
662 "\tlink to busybox for each function they wish to use and BusyBox\n"
663 "\twill act like whatever it was invoked as.\n"
664 "\n"
665 "Currently defined functions:\n");
666 col = 0;
667 a = applet_names;
668 /* prevent last comma to be in the very last pos */
669 output_width--;
670 while (*a) {
671 int len2 = strlen(a) + 2;
672 if (col >= (int)output_width - len2) {
673 full_write2_str(",\n");
674 col = 0;
675 }
676 if (col == 0) {
677 col = 6;
678 full_write2_str("\t");
679 } else {
680 full_write2_str(", ");
681 }
682 full_write2_str(a);
683 col += len2;
684 a += len2 - 1;
685 }
686 full_write2_str("\n\n");
687 return 0;
688 }
689
690 if (ENABLE_FEATURE_INSTALLER && strcmp(argv[1], "--install") == 0) {
691 int use_symbolic_links;
692 const char *busybox;
693 busybox = xmalloc_readlink(bb_busybox_exec_path);
694 if (!busybox)
695 busybox = bb_busybox_exec_path;
696 /* busybox --install [-s] [DIR]: */
697 /* -s: make symlinks */
698 /* DIR: directory to install links to */
699 use_symbolic_links = (argv[2] && strcmp(argv[2], "-s") == 0 && argv++);
700 install_links(busybox, use_symbolic_links, argv[2]);
701 return 0;
702 }
703
704 if (strcmp(argv[1], "--help") == 0) {
705 /* "busybox --help [<applet>]" */
706 if (!argv[2])
707 goto help;
708 /* convert to "<applet> --help" */
709 argv[0] = argv[2];
710 argv[2] = NULL;
711 } else {
712 /* "busybox <applet> arg1 arg2 ..." */
713 argv++;
714 }
715 /* We support "busybox /a/path/to/applet args..." too. Allows for
716 * "#!/bin/busybox"-style wrappers */
717 applet_name = bb_get_last_path_component_nostrip(argv[0]);
718 run_applet_and_exit(applet_name, argv);
719
720 /*bb_error_msg_and_die("applet not found"); - sucks in printf */
721 full_write2_str(applet_name);
722 full_write2_str(": applet not found\n");
723 xfunc_die();
724 }
725
726 void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
727 {
728 int argc = 1;
729
730 while (argv[argc])
731 argc++;
732
733 /* Reinit some shared global data */
734 xfunc_error_retval = EXIT_FAILURE;
735
736 applet_name = APPLET_NAME(applet_no);
737 if (argc == 2 && strcmp(argv[1], "--help") == 0) {
738 /* Special case. POSIX says "test --help"
739 * should be no different from e.g. "test --foo". */
740 //TODO: just compare applet_no with APPLET_NO_test
741 if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
742 bb_show_usage();
743 }
744 if (ENABLE_FEATURE_SUID)
745 check_suid(applet_no);
746 exit(applet_main[applet_no](argc, argv));
747 }
748
749 void FAST_FUNC run_applet_and_exit(const char *name, char **argv)
750 {
751 int applet = find_applet_by_name(name);
752 if (applet >= 0)
753 run_applet_no_and_exit(applet, argv);
754 if (!strncmp(name, "busybox", 7))
755 exit(busybox_main(argv));
756 }
757
758 #endif /* !defined(SINGLE_APPLET_MAIN) */
759
760
761
762 #if ENABLE_BUILD_LIBBUSYBOX
763 int lbb_main(char **argv)
764 #else
765 int main(int argc UNUSED_PARAM, char **argv)
766 #endif
767 {
768 /* Tweak malloc for reduced memory consumption */
769 #ifndef PAGE_SIZE
770 # define PAGE_SIZE (4*1024) /* guess */
771 #endif
772 #ifdef M_TRIM_THRESHOLD
773 /* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
774 * to keep before releasing to the OS
775 * Default is way too big: 256k
776 */
777 mallopt(M_TRIM_THRESHOLD, 2 * PAGE_SIZE);
778 #endif
779 #ifdef M_MMAP_THRESHOLD
780 /* M_MMAP_THRESHOLD is the request size threshold for using mmap()
781 * Default is too big: 256k
782 */
783 mallopt(M_MMAP_THRESHOLD, 8 * PAGE_SIZE - 256);
784 #endif
785
786 #if defined(SINGLE_APPLET_MAIN)
787 /* Only one applet is selected by the user! */
788 /* applet_names in this case is just "applet\0\0" */
789 lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
790 return SINGLE_APPLET_MAIN(argc, argv);
791 #else
792 lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
793
794 #if !BB_MMU
795 /* NOMMU re-exec trick sets high-order bit in first byte of name */
796 if (argv[0][0] & 0x80) {
797 re_execed = 1;
798 argv[0][0] &= 0x7f;
799 }
800 #endif
801 applet_name = argv[0];
802 if (applet_name[0] == '-')
803 applet_name++;
804 applet_name = bb_basename(applet_name);
805
806 parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
807
808 run_applet_and_exit(applet_name, argv);
809
810 /*bb_error_msg_and_die("applet not found"); - sucks in printf */
811 full_write2_str(applet_name);
812 full_write2_str(": applet not found\n");
813 xfunc_die();
814 #endif
815 }