1 /* vi: set sw=4 ts=4: */
2 /*
3 * universal getopt32 implementation for busybox
4 *
5 * Copyright (C) 2003-2005 Vladimir Oleynik <dzo@simtreas.ru>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9
10 #if ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG
11 # include <getopt.h>
12 #endif
13 #include "libbb.h"
14
15 /* Documentation
16
17 uint32_t
18 getopt32(char **argv, const char *applet_opts, ...)
19
20 The command line options are passed as the applet_opts string.
21
22 If one of the given options is found, a flag value is added to
23 the return value.
24
25 The flag value is determined by the position of the char in
26 applet_opts string. For example:
27
28 flags = getopt32(argv, "rnug");
29
30 "r" will set 1 (bit 0)
31 "n" will set 2 (bit 1)
32 "u" will set 4 (bit 2)
33 "g" will set 8 (bit 3)
34
35 and so on. You can also look at the return value as a bit
36 field and each option sets one bit.
37
38 On exit, global variable optind is set so that if you
39 will do argc -= optind; argv += optind; then
40 argc will be equal to number of remaining non-option
41 arguments, first one would be in argv[0], next in argv[1] and so on
42 (options and their parameters will be moved into argv[]
43 positions prior to argv[optind]).
44
45 "o:" If one of the options requires an argument, then add a ":"
46 after the char in applet_opts and provide a pointer to store
47 the argument. For example:
48
49 char *pointer_to_arg_for_a;
50 char *pointer_to_arg_for_b;
51 char *pointer_to_arg_for_c;
52 char *pointer_to_arg_for_d;
53
54 flags = getopt32(argv, "a:b:c:d:",
55 &pointer_to_arg_for_a, &pointer_to_arg_for_b,
56 &pointer_to_arg_for_c, &pointer_to_arg_for_d);
57
58 The type of the pointer may be controlled by "o::" or "o+" in
59 the external string opt_complementary (see below for more info).
60
61 "o::" If option can have an *optional* argument, then add a "::"
62 after its char in applet_opts and provide a pointer to store
63 the argument. Note that optional arguments _must_
64 immediately follow the option: -oparam, not -o param.
65
66 "o:+" This means that the parameter for this option is a nonnegative integer.
67 It will be processed with xatoi_positive() - allowed range
68 is 0..INT_MAX.
69
70 int param; // "unsigned param;" will also work
71 getopt32(argv, "p:+", ¶m);
72
73 "o:*" This means that the option can occur multiple times. Each occurrence
74 will be saved as a llist_t element instead of char*.
75
76 For example:
77 The grep applet can have one or more "-e pattern" arguments.
78 In this case you should use getopt32() as follows:
79
80 llist_t *patterns = NULL;
81
82 (this pointer must be initializated to NULL if the list is empty
83 as required by llist_add_to_end(llist_t **old_head, char *new_item).)
84
85 getopt32(argv, "e:*", &patterns);
86
87 $ grep -e user -e root /etc/passwd
88 root:x:0:0:root:/root:/bin/bash
89 user:x:500:500::/home/user:/bin/bash
90
91 "+" If the first character in the applet_opts string is a plus,
92 then option processing will stop as soon as a non-option is
93 encountered in the argv array. Useful for applets like env
94 which should not process arguments to subprograms:
95 env -i ls -d /
96 Here we want env to process just the '-i', not the '-d'.
97
98 "!" Report bad option, missing required options,
99 inconsistent options with all-ones return value (instead of abort).
100
101 const char *applet_long_options
102
103 This struct allows you to define long options:
104
105 static const char applet_longopts[] ALIGN1 =
106 //"name\0" has_arg val
107 "verbose\0" No_argument "v"
108 ;
109 applet_long_options = applet_longopts;
110
111 The last member of struct option (val) typically is set to
112 matching short option from applet_opts. If there is no matching
113 char in applet_opts, then:
114 - return bit has next position after short options
115 - if has_arg is not "No_argument", use ptr for arg also
116 - opt_complementary affects it too
117
118 Note: a good applet will make long options configurable via the
119 config process and not a required feature. The current standard
120 is to name the config option CONFIG_FEATURE_<applet>_LONG_OPTIONS.
121
122 const char *opt_complementary
123
124 ":" The colon (":") is used to separate groups of two or more chars
125 and/or groups of chars and special characters (stating some
126 conditions to be checked).
127
128 "abc" If groups of two or more chars are specified, the first char
129 is the main option and the other chars are secondary options.
130 Their flags will be turned on if the main option is found even
131 if they are not specifed on the command line. For example:
132
133 opt_complementary = "abc";
134 flags = getopt32(argv, "abcd")
135
136 If getopt() finds "-a" on the command line, then
137 getopt32's return value will be as if "-a -b -c" were
138 found.
139
140 "ww" Adjacent double options have a counter associated which indicates
141 the number of occurrences of the option.
142 For example the ps applet needs:
143 if w is given once, GNU ps sets the width to 132,
144 if w is given more than once, it is "unlimited"
145
146 int w_counter = 0; // must be initialized!
147 opt_complementary = "ww";
148 getopt32(argv, "w", &w_counter);
149 if (w_counter)
150 width = (w_counter == 1) ? 132 : INT_MAX;
151 else
152 get_terminal_width(...&width...);
153
154 w_counter is a pointer to an integer. It has to be passed to
155 getopt32() after all other option argument sinks.
156
157 For example: accept multiple -v to indicate the level of verbosity
158 and for each -b optarg, add optarg to my_b. Finally, if b is given,
159 turn off c and vice versa:
160
161 llist_t *my_b = NULL;
162 int verbose_level = 0;
163 opt_complementary = "vv:b-c:c-b";
164 f = getopt32(argv, "vb:*c", &my_b, &verbose_level);
165 if (f & 2) // -c after -b unsets -b flag
166 while (my_b) dosomething_with(llist_pop(&my_b));
167 if (my_b) // but llist is stored if -b is specified
168 free_llist(my_b);
169 if (verbose_level) printf("verbose level is %d\n", verbose_level);
170
171 Special characters:
172
173 "-" A group consisting of just a dash forces all arguments
174 to be treated as options, even if they have no leading dashes.
175 Next char in this case can't be a digit (0-9), use ':' or end of line.
176 Example:
177
178 opt_complementary = "-:w-x:x-w"; // "-w-x:x-w" would also work,
179 getopt32(argv, "wx"); // but is less readable
180
181 This makes it possible to use options without a dash (./program w x)
182 as well as with a dash (./program -x).
183
184 NB: getopt32() will leak a small amount of memory if you use
185 this option! Do not use it if there is a possibility of recursive
186 getopt32() calls.
187
188 "--" A double dash at the beginning of opt_complementary means the
189 argv[1] string should always be treated as options, even if it isn't
190 prefixed with a "-". This is useful for special syntax in applets
191 such as "ar" and "tar":
192 tar xvf foo.tar
193
194 NB: getopt32() will leak a small amount of memory if you use
195 this option! Do not use it if there is a possibility of recursive
196 getopt32() calls.
197
198 "-N" A dash as the first char in a opt_complementary group followed
199 by a single digit (0-9) means that at least N non-option
200 arguments must be present on the command line
201
202 "=N" An equal sign as the first char in a opt_complementary group followed
203 by a single digit (0-9) means that exactly N non-option
204 arguments must be present on the command line
205
206 "?N" A "?" as the first char in a opt_complementary group followed
207 by a single digit (0-9) means that at most N arguments must be present
208 on the command line.
209
210 "V-" An option with dash before colon or end-of-line results in
211 bb_show_usage() being called if this option is encountered.
212 This is typically used to implement "print verbose usage message
213 and exit" option.
214
215 "a-b" A dash between two options causes the second of the two
216 to be unset (and ignored) if it is given on the command line.
217
218 [FIXME: what if they are the same? like "x-x"? Is it ever useful?]
219
220 For example:
221 The du applet has the options "-s" and "-d depth". If
222 getopt32 finds -s, then -d is unset or if it finds -d
223 then -s is unset. (Note: busybox implements the GNU
224 "--max-depth" option as "-d".) To obtain this behavior, you
225 set opt_complementary = "s-d:d-s". Only one flag value is
226 added to getopt32's return value depending on the
227 position of the options on the command line. If one of the
228 two options requires an argument pointer (":" in applet_opts
229 as in "d:") optarg is set accordingly.
230
231 char *smax_print_depth;
232
233 opt_complementary = "s-d:d-s:x-x";
234 opt = getopt32(argv, "sd:x", &smax_print_depth);
235
236 if (opt & 2)
237 max_print_depth = atoi(smax_print_depth);
238 if (opt & 4)
239 printf("Detected odd -x usage\n");
240
241 "a--b" A double dash between two options, or between an option and a group
242 of options, means that they are mutually exclusive. Unlike
243 the "-" case above, an error will be forced if the options
244 are used together.
245
246 For example:
247 The cut applet must have only one type of list specified, so
248 -b, -c and -f are mutually exclusive and should raise an error
249 if specified together. In this case you must set
250 opt_complementary = "b--cf:c--bf:f--bc". If two of the
251 mutually exclusive options are found, getopt32 will call
252 bb_show_usage() and die.
253
254 "x--x" Variation of the above, it means that -x option should occur
255 at most once.
256
257 "o+" A plus after a char in opt_complementary means that the parameter
258 for this option is a nonnegative integer. It will be processed
259 with xatoi_positive() - allowed range is 0..INT_MAX.
260
261 int param; // "unsigned param;" will also work
262 opt_complementary = "p+";
263 getopt32(argv, "p:", ¶m);
264
265 "o::" A double colon after a char in opt_complementary means that the
266 option can occur multiple times. Each occurrence will be saved as
267 a llist_t element instead of char*.
268
269 For example:
270 The grep applet can have one or more "-e pattern" arguments.
271 In this case you should use getopt32() as follows:
272
273 llist_t *patterns = NULL;
274
275 (this pointer must be initializated to NULL if the list is empty
276 as required by llist_add_to_end(llist_t **old_head, char *new_item).)
277
278 opt_complementary = "e::";
279 getopt32(argv, "e:", &patterns);
280
281 $ grep -e user -e root /etc/passwd
282 root:x:0:0:root:/root:/bin/bash
283 user:x:500:500::/home/user:/bin/bash
284
285 "o+" and "o::" can be handled by "o:+" and "o:*" specifiers
286 in option string (and it is preferred), but this does not work
287 for "long options only" cases, such as tar --exclude=PATTERN,
288 wget --header=HDR cases.
289
290 "a?b" A "?" between an option and a group of options means that
291 at least one of them is required to occur if the first option
292 occurs in preceding command line arguments.
293
294 For example from "id" applet:
295
296 // Don't allow -n -r -rn -ug -rug -nug -rnug
297 opt_complementary = "r?ug:n?ug:u--g:g--u";
298 flags = getopt32(argv, "rnug");
299
300 This example allowed only:
301 $ id; id -u; id -g; id -ru; id -nu; id -rg; id -ng; id -rnu; id -rng
302
303 "X" A opt_complementary group with just a single letter means
304 that this option is required. If more than one such group exists,
305 at least one option is required to occur (not all of them).
306 For example from "start-stop-daemon" applet:
307
308 // Don't allow -KS -SK, but -S or -K is required
309 opt_complementary = "K:S:K--S:S--K";
310 flags = getopt32(argv, "KS...);
311
312
313 Don't forget to use ':'. For example, "?322-22-23X-x-a"
314 is interpreted as "?3:22:-2:2-2:2-3Xa:2--x" -
315 max 3 args; count uses of '-2'; min 2 args; if there is
316 a '-2' option then unset '-3', '-X' and '-a'; if there is
317 a '-2' and after it a '-x' then error out.
318 But it's far too obfuscated. Use ':' to separate groups.
319 */
320
321 /* Code here assumes that 'unsigned' is at least 32 bits wide */
322
323 const char *const bb_argv_dash[] = { "-", NULL };
324
325 const char *opt_complementary;
326
327 enum {
328 PARAM_STRING,
329 PARAM_LIST,
330 PARAM_INT,
331 };
332
333 typedef struct {
334 unsigned char opt_char;
335 smallint param_type;
336 unsigned switch_on;
337 unsigned switch_off;
338 unsigned incongruously;
339 unsigned requires;
340 void **optarg; /* char**, llist_t** or int *. */
341 int *counter;
342 } t_complementary;
343
344 /* You can set applet_long_options for parse called long options */
345 #if ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG
346 static const struct option bb_null_long_options[1] = {
347 { 0, 0, 0, 0 }
348 };
349 const char *applet_long_options;
350 #endif
351
352 uint32_t option_mask32;
353
354 uint32_t FAST_FUNC
getopt32(char ** argv,const char * applet_opts,...)355 getopt32(char **argv, const char *applet_opts, ...)
356 {
357 int argc;
358 unsigned flags = 0;
359 unsigned requires = 0;
360 t_complementary complementary[33]; /* last stays zero-filled */
361 char first_char;
362 int c;
363 const unsigned char *s;
364 t_complementary *on_off;
365 va_list p;
366 #if ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG
367 const struct option *l_o;
368 struct option *long_options = (struct option *) &bb_null_long_options;
369 #endif
370 unsigned trigger;
371 char **pargv;
372 int min_arg = 0;
373 int max_arg = -1;
374
375 #define SHOW_USAGE_IF_ERROR 1
376 #define ALL_ARGV_IS_OPTS 2
377 #define FIRST_ARGV_IS_OPT 4
378
379 int spec_flgs = 0;
380
381 /* skip 0: some applets cheat: they do not actually HAVE argv[0] */
382 argc = 1;
383 while (argv[argc])
384 argc++;
385
386 va_start(p, applet_opts);
387
388 on_off = complementary;
389 memset(on_off, 0, sizeof(complementary));
390
391 applet_opts = strcpy(alloca(strlen(applet_opts) + 1), applet_opts);
392
393 /* skip bbox extension */
394 first_char = applet_opts[0];
395 if (first_char == '!')
396 applet_opts++;
397
398 /* skip GNU extension */
399 s = (const unsigned char *)applet_opts;
400 if (*s == '+' || *s == '-')
401 s++;
402 c = 0;
403 while (*s) {
404 if (c >= 32)
405 break;
406 on_off->opt_char = *s;
407 on_off->switch_on = (1 << c);
408 if (*++s == ':') {
409 on_off->optarg = va_arg(p, void **);
410 if (s[1] == '+' || s[1] == '*') {
411 /* 'o:+' or 'o:*' */
412 on_off->param_type = (s[1] == '+') ?
413 PARAM_INT : PARAM_LIST;
414 overlapping_strcpy((char*)s + 1, (char*)s + 2);
415 }
416 /* skip possible 'o::' (or 'o:+:' !) */
417 while (*++s == ':')
418 continue;
419 }
420 on_off++;
421 c++;
422 }
423
424 #if ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG
425 if (applet_long_options) {
426 const char *optstr;
427 unsigned i, count;
428
429 count = 1;
430 optstr = applet_long_options;
431 while (optstr[0]) {
432 optstr += strlen(optstr) + 3; /* skip NUL, has_arg, val */
433 count++;
434 }
435 /* count == no. of longopts + 1 */
436 long_options = alloca(count * sizeof(*long_options));
437 memset(long_options, 0, count * sizeof(*long_options));
438 i = 0;
439 optstr = applet_long_options;
440 while (--count) {
441 long_options[i].name = optstr;
442 optstr += strlen(optstr) + 1;
443 long_options[i].has_arg = (unsigned char)(*optstr++);
444 /* long_options[i].flag = NULL; */
445 long_options[i].val = (unsigned char)(*optstr++);
446 i++;
447 }
448 for (l_o = long_options; l_o->name; l_o++) {
449 if (l_o->flag)
450 continue;
451 for (on_off = complementary; on_off->opt_char; on_off++)
452 if (on_off->opt_char == l_o->val)
453 goto next_long;
454 if (c >= 32)
455 break;
456 on_off->opt_char = l_o->val;
457 on_off->switch_on = (1 << c);
458 if (l_o->has_arg != no_argument)
459 on_off->optarg = va_arg(p, void **);
460 c++;
461 next_long: ;
462 }
463 /* Make it unnecessary to clear applet_long_options
464 * by hand after each call to getopt32
465 */
466 applet_long_options = NULL;
467 }
468 #endif /* ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG */
469
470 for (s = (const unsigned char *)opt_complementary; s && *s; s++) {
471 t_complementary *pair;
472 unsigned *pair_switch;
473
474 if (*s == ':')
475 continue;
476 c = s[1];
477 if (*s == '?') {
478 if (c < '0' || c > '9') {
479 spec_flgs |= SHOW_USAGE_IF_ERROR;
480 } else {
481 max_arg = c - '0';
482 s++;
483 }
484 continue;
485 }
486 if (*s == '-') {
487 if (c < '0' || c > '9') {
488 if (c == '-') {
489 spec_flgs |= FIRST_ARGV_IS_OPT;
490 s++;
491 } else
492 spec_flgs |= ALL_ARGV_IS_OPTS;
493 } else {
494 min_arg = c - '0';
495 s++;
496 }
497 continue;
498 }
499 if (*s == '=') {
500 min_arg = max_arg = c - '0';
501 s++;
502 continue;
503 }
504 for (on_off = complementary; on_off->opt_char; on_off++)
505 if (on_off->opt_char == *s)
506 goto found_opt;
507 /* Without this, diagnostic of such bugs is not easy */
508 bb_error_msg_and_die("NO OPT %c!", *s);
509 found_opt:
510 if (c == ':' && s[2] == ':') {
511 on_off->param_type = PARAM_LIST;
512 continue;
513 }
514 if (c == '+' && (s[2] == ':' || s[2] == '\0')) {
515 on_off->param_type = PARAM_INT;
516 s++;
517 continue;
518 }
519 if (c == ':' || c == '\0') {
520 requires |= on_off->switch_on;
521 continue;
522 }
523 if (c == '-' && (s[2] == ':' || s[2] == '\0')) {
524 flags |= on_off->switch_on;
525 on_off->incongruously |= on_off->switch_on;
526 s++;
527 continue;
528 }
529 if (c == *s) {
530 on_off->counter = va_arg(p, int *);
531 s++;
532 }
533 pair = on_off;
534 pair_switch = &pair->switch_on;
535 for (s++; *s && *s != ':'; s++) {
536 if (*s == '?') {
537 pair_switch = &pair->requires;
538 } else if (*s == '-') {
539 if (pair_switch == &pair->switch_off)
540 pair_switch = &pair->incongruously;
541 else
542 pair_switch = &pair->switch_off;
543 } else {
544 for (on_off = complementary; on_off->opt_char; on_off++)
545 if (on_off->opt_char == *s) {
546 *pair_switch |= on_off->switch_on;
547 break;
548 }
549 }
550 }
551 s--;
552 }
553 opt_complementary = NULL;
554 va_end(p);
555
556 if (spec_flgs & (FIRST_ARGV_IS_OPT | ALL_ARGV_IS_OPTS)) {
557 pargv = argv + 1;
558 while (*pargv) {
559 if (pargv[0][0] != '-' && pargv[0][0] != '\0') {
560 /* Can't use alloca: opts with params will
561 * return pointers to stack!
562 * NB: we leak these allocations... */
563 char *pp = xmalloc(strlen(*pargv) + 2);
564 *pp = '-';
565 strcpy(pp + 1, *pargv);
566 *pargv = pp;
567 }
568 if (!(spec_flgs & ALL_ARGV_IS_OPTS))
569 break;
570 pargv++;
571 }
572 }
573
574 /* In case getopt32 was already called:
575 * reset the libc getopt() function, which keeps internal state.
576 * run_nofork_applet() does this, but we might end up here
577 * also via gunzip_main() -> gzip_main(). Play safe.
578 */
579 #ifdef __GLIBC__
580 optind = 0;
581 #else /* BSD style */
582 optind = 1;
583 /* optreset = 1; */
584 #endif
585 /* optarg = NULL; opterr = 0; optopt = 0; - do we need this?? */
586
587 /* Note: just "getopt() <= 0" will not work well for
588 * "fake" short options, like this one:
589 * wget $'-\203' "Test: test" http://kernel.org/
590 * (supposed to act as --header, but doesn't) */
591 #if ENABLE_LONG_OPTS || ENABLE_FEATURE_GETOPT_LONG
592 while ((c = getopt_long(argc, argv, applet_opts,
593 long_options, NULL)) != -1) {
594 #else
595 while ((c = getopt(argc, argv, applet_opts)) != -1) {
596 #endif
597 /* getopt prints "option requires an argument -- X"
598 * and returns '?' if an option has no arg, but one is reqd */
599 c &= 0xff; /* fight libc's sign extension */
600 for (on_off = complementary; on_off->opt_char != c; on_off++) {
601 /* c can be NUL if long opt has non-NULL ->flag,
602 * but we construct long opts so that flag
603 * is always NULL (see above) */
604 if (on_off->opt_char == '\0' /* && c != '\0' */) {
605 /* c is probably '?' - "bad option" */
606 goto error;
607 }
608 }
609 if (flags & on_off->incongruously)
610 goto error;
611 trigger = on_off->switch_on & on_off->switch_off;
612 flags &= ~(on_off->switch_off ^ trigger);
613 flags |= on_off->switch_on ^ trigger;
614 flags ^= trigger;
615 if (on_off->counter)
616 (*(on_off->counter))++;
617 if (optarg) {
618 if (on_off->param_type == PARAM_LIST) {
619 llist_add_to_end((llist_t **)(on_off->optarg), optarg);
620 } else if (on_off->param_type == PARAM_INT) {
621 //TODO: xatoi_positive indirectly pulls in printf machinery
622 *(unsigned*)(on_off->optarg) = xatoi_positive(optarg);
623 } else if (on_off->optarg) {
624 *(char **)(on_off->optarg) = optarg;
625 }
626 }
627 }
628
629 /* check depending requires for given options */
630 for (on_off = complementary; on_off->opt_char; on_off++) {
631 if (on_off->requires
632 && (flags & on_off->switch_on)
633 && (flags & on_off->requires) == 0
634 ) {
635 goto error;
636 }
637 }
638 if (requires && (flags & requires) == 0)
639 goto error;
640 argc -= optind;
641 if (argc < min_arg || (max_arg >= 0 && argc > max_arg))
642 goto error;
643
644 option_mask32 = flags;
645 return flags;
646
647 error:
648 if (first_char != '!')
649 bb_show_usage();
650 return (int32_t)-1;
651 }
652