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#if ENABLE_LONG_OPTS 10# include <getopt.h> 11#endif 12#include "libbb.h" 13 14//kbuild:lib-y += getopt32.o 15 16/* Documentation 17 18uint32_t 19getopt32(char **argv, const char *applet_opts, ...) 20 21 The command line options are passed as the applet_opts string. 22 23 If one of the given options is found, a flag value is added to 24 the return value. 25 26 The flag value is determined by the position of the char in 27 applet_opts string. For example: 28 29 flags = getopt32(argv, "rnug"); 30 31 "r" will set 1 (bit 0) 32 "n" will set 2 (bit 1) 33 "u" will set 4 (bit 2) 34 "g" will set 8 (bit 3) 35 36 and so on. You can also look at the return value as a bit 37 field and each option sets one bit. 38 39 On exit, global variable optind is set so that if you 40 will do argc -= optind; argv += optind; then 41 argc will be equal to number of remaining non-option 42 arguments, first one would be in argv[0], next in argv[1] and so on 43 (options and their parameters will be moved into argv[] 44 positions prior to argv[optind]). 45 46 "o:" If one of the options requires an argument, then add a ":" 47 after the char in applet_opts and provide a pointer to store 48 the argument. For example: 49 50 char *pointer_to_arg_for_a; 51 char *pointer_to_arg_for_b; 52 char *pointer_to_arg_for_c; 53 char *pointer_to_arg_for_d; 54 55 flags = getopt32(argv, "a:b:c:d:", 56 &pointer_to_arg_for_a, &pointer_to_arg_for_b, 57 &pointer_to_arg_for_c, &pointer_to_arg_for_d); 58 59 The type of the pointer may be controlled by "o::" or "o+" in 60 the external string opt_complementary (see below for more info). 61 62 "o::" If option can have an *optional* argument, then add a "::" 63 after its char in applet_opts and provide a pointer to store 64 the argument. Note that optional arguments _must_ 65 immediately follow the option: -oparam, not -o param. 66 67 "o:+" This means that the parameter for this option is a nonnegative integer. 68 It will be processed with xatoi_positive() - allowed range 69 is 0..INT_MAX. 70 71 int param; // "unsigned param;" will also work 72 getopt32(argv, "p:+", ¶m); 73 74 "o:*" This means that the option can occur multiple times. Each occurrence 75 will be saved as a llist_t element instead of char*. 76 77 For example: 78 The grep applet can have one or more "-e pattern" arguments. 79 In this case you should use getopt32() as follows: 80 81 llist_t *patterns = NULL; 82 83 (this pointer must be initializated to NULL if the list is empty 84 as required by llist_add_to_end(llist_t **old_head, char *new_item).) 85 86 getopt32(argv, "e:*", &patterns); 87 88 $ grep -e user -e root /etc/passwd 89 root:x:0:0:root:/root:/bin/bash 90 user:x:500:500::/home/user:/bin/bash 91 92 "+" If the first character in the applet_opts string is a plus, 93 then option processing will stop as soon as a non-option is 94 encountered in the argv array. Useful for applets like env 95 which should not process arguments to subprograms: 96 env -i ls -d / 97 Here we want env to process just the '-i', not the '-d'. 98 99 "!" Report bad options, missing required options, 100 inconsistent options with all-ones return value (instead of abort). 101 102 "^" options string is "^optchars""\0""opt_complementary". 103 104uint32_t 105getopt32long(char **argv, const char *applet_opts, const char *logopts...) 106 107 This allows you to define long options: 108 109 static const char applet_longopts[] ALIGN1 = 110 //"name\0" has_arg val 111 "verbose\0" No_argument "v" 112 ; 113 opt = getopt32long(argv, applet_opts, applet_longopts, ...); 114 115 The last element (val) typically is set to 116 matching short option from applet_opts. If there is no matching 117 char in applet_opts, then: 118 - return bit has next position after short options 119 - if has_arg is not "No_argument", use ptr for arg also 120 - opt_complementary affects it too 121 122 Note: a good applet will make long options configurable via the 123 config process and not a required feature. The current standard 124 is to name the config option CONFIG_FEATURE_<applet>_LONG_OPTIONS. 125 126opt_complementary - option modifiers. 127 128 ":" The colon (":") is used to separate groups of two or more chars 129 and/or groups of chars and special characters (stating some 130 conditions to be checked). 131 132 "abc" If groups of two or more chars are specified, the first char 133 is the main option and the other chars are secondary options. 134 Their flags will be turned on if the main option is found even 135 if they are not specified on the command line. For example: 136 137 flags = getopt32(argv, "^abcd""\0""abc") 138 139 If getopt() finds "-a" on the command line, then 140 getopt32's return value will be as if "-a -b -c" were 141 found. 142 143 "ww" Adjacent double options have a counter associated which indicates 144 the number of occurrences of the option. 145 For example the ps applet needs: 146 if w is given once, GNU ps sets the width to 132, 147 if w is given more than once, it is "unlimited" 148 149 int w_counter = 0; // must be initialized! 150 getopt32(argv, "^w""\0""ww", &w_counter); 151 if (w_counter) 152 width = (w_counter == 1) ? 132 : INT_MAX; 153 else 154 get_terminal_width(...&width...); 155 156 w_counter is a pointer to an integer. It has to be passed to 157 getopt32() after all other option argument sinks. 158 159 For example: accept multiple -v to indicate the level of verbosity 160 and for each -b optarg, add optarg to my_b. Finally, if b is given, 161 turn off c and vice versa: 162 163 llist_t *my_b = NULL; 164 int verbose_level = 0; 165 f = getopt32(argv, "^vb:*c" 166 "\0""vv:b-c:c-b" 167 , &my_b, &verbose_level); 168 if (f & 2) // -c after -b unsets -b flag 169 while (my_b) dosomething_with(llist_pop(&my_b)); 170 if (my_b) // but llist is stored if -b is specified 171 free_llist(my_b); 172 if (verbose_level) printf("verbose level is %d\n", verbose_level); 173 174Special characters: 175 176 "-N" A dash as the first char in a opt_complementary group followed 177 by a single digit (0-9) means that at least N non-option 178 arguments must be present on the command line 179 180 "=N" An equal sign as the first char in a opt_complementary group followed 181 by a single digit (0-9) means that exactly N non-option 182 arguments must be present on the command line 183 184 "?N" A "?" as the first char in a opt_complementary group followed 185 by a single digit (0-9) means that at most N arguments must be present 186 on the command line. 187 188 "V-" An option with dash before colon or end-of-line results in 189 bb_show_usage() being called if this option is encountered. 190 This is typically used to implement "print verbose usage message 191 and exit" option. 192 193 "a-b" A dash between two options causes the second of the two 194 to be unset (and ignored) if it is given on the command line. 195 196 [FIXME: what if they are the same? like "x-x"? Is it ever useful?] 197 198 For example: 199 The du applet has the options "-s" and "-d depth". If 200 getopt32 finds -s, then -d is unset or if it finds -d 201 then -s is unset. (Note: busybox implements the GNU 202 "--max-depth" option as "-d".) To obtain this behavior, you 203 set opt_complementary to "s-d:d-s". Only one flag value is 204 added to getopt32's return value depending on the 205 position of the options on the command line. If one of the 206 two options requires an argument pointer (":" in applet_opts 207 as in "d:") optarg is set accordingly. 208 209 char *smax_print_depth; 210 211 opt = getopt32(argv, "^sd:x""\0""s-d:d-s:x-x", &smax_print_depth); 212 213 if (opt & 2) 214 max_print_depth = atoi(smax_print_depth); 215 if (opt & 4) 216 printf("Detected odd -x usage\n"); 217 218 "a--b" A double dash between two options, or between an option and a group 219 of options, means that they are mutually exclusive. Unlike 220 the "-" case above, an error will be forced if the options 221 are used together. 222 223 For example: 224 The cut applet must have only one type of list specified, so 225 -b, -c and -f are mutually exclusive and should raise an error 226 if specified together. In this case you must set 227 opt_complementary to "b--cf:c--bf:f--bc". If two of the 228 mutually exclusive options are found, getopt32 will call 229 bb_show_usage() and die. 230 231 "x--x" Variation of the above, it means that -x option should occur 232 at most once. 233 234 "o+" A plus after a char in opt_complementary means that the parameter 235 for this option is a nonnegative integer. It will be processed 236 with xatoi_positive() - allowed range is 0..INT_MAX. 237 238 int param; // "unsigned param;" will also work 239 getopt32(argv, "^p:""\0""p+", ¶m); 240 241 "o::" A double colon after a char in opt_complementary means that the 242 option can occur multiple times. Each occurrence will be saved as 243 a llist_t element instead of char*. 244 245 For example: 246 The grep applet can have one or more "-e pattern" arguments. 247 In this case you should use getopt32() as follows: 248 249 llist_t *patterns = NULL; 250 251 (this pointer must be initializated to NULL if the list is empty 252 as required by llist_add_to_end(llist_t **old_head, char *new_item).) 253 254 getopt32(argv, "^e:""\0""e::", &patterns); 255 256 $ grep -e user -e root /etc/passwd 257 root:x:0:0:root:/root:/bin/bash 258 user:x:500:500::/home/user:/bin/bash 259 260 "o+" and "o::" can be handled by "o:+" and "o:*" specifiers 261 in option string (and it is preferred), but this does not work 262 for "long options only" cases, such as tar --exclude=PATTERN, 263 wget --header=HDR cases. 264 265 "a?b" A "?" between an option and a group of options means that 266 at least one of them is required to occur if the first option 267 occurs in preceding command line arguments. 268 269 For example from "id" applet: 270 271 // Don't allow -n -r -rn -ug -rug -nug -rnug 272 flags = getopt32(argv, "^rnug""\0""r?ug:n?ug:u--g:g--u"); 273 274 This example allowed only: 275 $ id; id -u; id -g; id -ru; id -nu; id -rg; id -ng; id -rnu; id -rng 276 277 "X" A opt_complementary group with just a single letter means 278 that this option is required. If more than one such group exists, 279 at least one option is required to occur (not all of them). 280 For example from "start-stop-daemon" applet: 281 282 // Don't allow -KS -SK, but -S or -K is required 283 flags = getopt32(argv, "^KS...""\0""K:S:K--S:S--K"); 284 285 286 Don't forget to use ':'. For example, "?322-22-23X-x-a" 287 is interpreted as "?3:22:-2:2-2:2-3Xa:2--x" - 288 max 3 args; count uses of '-2'; min 2 args; if there is 289 a '-2' option then unset '-3', '-X' and '-a'; if there is 290 a '-2' and after it a '-x' then error out. 291 But it's far too obfuscated. Use ':' to separate groups. 292*/ 293 294/* Code here assumes that 'unsigned' is at least 32 bits wide */ 295 296const char *const bb_argv_dash[] = { "-", NULL }; 297 298enum { 299 PARAM_STRING, 300 PARAM_LIST, 301 PARAM_INT, 302}; 303 304typedef struct { 305 unsigned char opt_char; 306 smallint param_type; 307 unsigned switch_on; 308 unsigned switch_off; 309 unsigned incongruously; 310 unsigned requires; 311 void **optarg; /* char**, llist_t** or int *. */ 312 int *counter; 313} t_complementary; 314 315uint32_t option_mask32; 316 317#if ENABLE_LONG_OPTS 318static const struct option bb_null_long_options[1] = { 319 { 0, 0, 0, 0 } 320}; 321#else 322#define vgetopt32(argv,applet_opts,applet_long_options,p) \ 323 vgetopt32(argv,applet_opts,p) 324#endif 325 326/* Please keep getopt32 free from xmalloc */ 327 328static uint32_t 329vgetopt32(char **argv, const char *applet_opts, const char *applet_long_options, va_list p) 330{ 331 int argc; 332 unsigned flags = 0; 333 unsigned requires = 0; 334 unsigned len; 335 t_complementary complementary[33]; /* last stays zero-filled */ 336 char dont_die_flag; 337 int c; 338 const unsigned char *s; 339 const char *opt_complementary; 340 t_complementary *on_off; 341#if ENABLE_LONG_OPTS 342 const struct option *l_o; 343 struct option *long_options = (struct option *) &bb_null_long_options; 344#endif 345 unsigned trigger; 346 int min_arg = 0; 347 int max_arg = -1; 348 int spec_flgs = 0; 349 350#define SHOW_USAGE_IF_ERROR 1 351 352 on_off = complementary; 353 memset(on_off, 0, sizeof(complementary)); 354 355 len = strlen(applet_opts); 356 357 /* skip bbox extension */ 358 opt_complementary = NULL; 359 if (applet_opts[0] == '^') { 360 applet_opts++; 361 /* point it past terminating NUL */ 362 opt_complementary = applet_opts + len; 363 } 364 365 /* skip another bbox extension */ 366 dont_die_flag = applet_opts[0]; 367 if (dont_die_flag == '!') 368 applet_opts++; 369 370 applet_opts = strcpy(alloca(len + 1), applet_opts); 371 372 /* skip GNU extension */ 373 s = (const unsigned char *)applet_opts; 374 if (*s == '+' || *s == '-') 375 s++; 376 c = 0; 377 while (*s) { 378 if (c >= 32) 379 break; 380 on_off->opt_char = *s; 381 on_off->switch_on = (1U << c); 382 if (*++s == ':') { 383 on_off->optarg = va_arg(p, void **); 384 if (s[1] == '+' || s[1] == '*') { 385 /* 'o:+' or 'o:*' */ 386 on_off->param_type = (s[1] == '+') ? 387 PARAM_INT : PARAM_LIST; 388 overlapping_strcpy((char*)s + 1, (char*)s + 2); 389 } 390 /* skip possible 'o::' (or 'o:+:' !) */ 391 while (*++s == ':') 392 continue; 393 } 394 on_off++; 395 c++; 396 } 397 398#if ENABLE_LONG_OPTS 399 if (applet_long_options) { 400 const char *optstr; 401 unsigned i, count; 402 403 count = 1; 404 optstr = applet_long_options; 405 while (optstr[0]) { 406 optstr += strlen(optstr) + 3; /* skip NUL, has_arg, val */ 407 count++; 408 } 409 /* count == no. of longopts + 1 */ 410 long_options = alloca(count * sizeof(*long_options)); 411 memset(long_options, 0, count * sizeof(*long_options)); 412 i = 0; 413 optstr = applet_long_options; 414 while (--count) { 415 long_options[i].name = optstr; 416 optstr += strlen(optstr) + 1; 417 long_options[i].has_arg = (unsigned char)(*optstr++); 418 /* long_options[i].flag = NULL; */ 419 long_options[i].val = (unsigned char)(*optstr++); 420 i++; 421 } 422 for (l_o = long_options; l_o->name; l_o++) { 423 if (l_o->flag) 424 continue; 425 for (on_off = complementary; on_off->opt_char; on_off++) 426 if (on_off->opt_char == l_o->val) 427 goto next_long; 428 if (c >= 32) 429 break; 430 on_off->opt_char = l_o->val; 431 on_off->switch_on = (1U << c); 432 if (l_o->has_arg != no_argument) 433 on_off->optarg = va_arg(p, void **); 434 c++; 435 next_long: ; 436 } 437 } 438#endif /* ENABLE_LONG_OPTS */ 439 440 s = (const unsigned char *)opt_complementary; 441 if (s) for (; *s; s++) { 442 t_complementary *pair; 443 unsigned *pair_switch; 444 445 if (*s == ':') 446 continue; 447 c = s[1]; 448 if (*s == '?') { 449 if (c < '0' || c > '9') { 450 spec_flgs |= SHOW_USAGE_IF_ERROR; 451 } else { 452 max_arg = c - '0'; 453 s++; 454 } 455 continue; 456 } 457 if (*s == '-') { 458 if (c >= '0' && c <= '9') { 459 min_arg = c - '0'; 460 s++; 461 } 462 continue; 463 } 464 if (*s == '=') { 465 min_arg = max_arg = c - '0'; 466 s++; 467 continue; 468 } 469 for (on_off = complementary; on_off->opt_char; on_off++) 470 if (on_off->opt_char == *s) 471 goto found_opt; 472 /* Without this, diagnostic of such bugs is not easy */ 473 bb_error_msg_and_die("NO OPT %c!", *s); 474 found_opt: 475 if (c == ':' && s[2] == ':') { 476 on_off->param_type = PARAM_LIST; 477 continue; 478 } 479 if (c == '+' && (s[2] == ':' || s[2] == '\0')) { 480 on_off->param_type = PARAM_INT; 481 s++; 482 continue; 483 } 484 if (c == ':' || c == '\0') { 485 requires |= on_off->switch_on; 486 continue; 487 } 488 if (c == '-' && (s[2] == ':' || s[2] == '\0')) { 489 flags |= on_off->switch_on; 490 on_off->incongruously |= on_off->switch_on; 491 s++; 492 continue; 493 } 494 if (c == *s) { 495 on_off->counter = va_arg(p, int *); 496 s++; 497 } 498 pair = on_off; 499 pair_switch = &pair->switch_on; 500 for (s++; *s && *s != ':'; s++) { 501 if (*s == '?') { 502 pair_switch = &pair->requires; 503 } else if (*s == '-') { 504 if (pair_switch == &pair->switch_off) 505 pair_switch = &pair->incongruously; 506 else 507 pair_switch = &pair->switch_off; 508 } else { 509 for (on_off = complementary; on_off->opt_char; on_off++) 510 if (on_off->opt_char == *s) { 511 *pair_switch |= on_off->switch_on; 512 break; 513 } 514 } 515 } 516 s--; 517 } 518 519 /* In case getopt32 was already called: 520 * reset libc getopt() internal state. 521 * run_nofork_applet() does this, but we might end up here 522 * also via gunzip_main() -> gzip_main(). Play safe. 523 */ 524 GETOPT_RESET(); 525 526 /* skip 0: some applets cheat: they do not actually HAVE argv[0] */ 527 argc = 1 + string_array_len(argv + 1); 528 529 /* Note: just "getopt() <= 0" will not work well for 530 * "fake" short options, like this one: 531 * wget $'-\203' "Test: test" http://kernel.org/ 532 * (supposed to act as --header, but doesn't) */ 533#if ENABLE_LONG_OPTS 534 while ((c = getopt_long(argc, argv, applet_opts, 535 long_options, NULL)) != -1) { 536#else 537 while ((c = getopt(argc, argv, applet_opts)) != -1) { 538#endif 539 /* getopt prints "option requires an argument -- X" 540 * and returns '?' if an option has no arg, but one is reqd */ 541 c &= 0xff; /* fight libc's sign extension */ 542 for (on_off = complementary; on_off->opt_char != c; on_off++) { 543 /* c can be NUL if long opt has non-NULL ->flag, 544 * but we construct long opts so that flag 545 * is always NULL (see above) */ 546 if (on_off->opt_char == '\0' /* && c != '\0' */) { 547 /* c is probably '?' - "bad option" */ 548 goto error; 549 } 550 } 551 if (flags & on_off->incongruously) 552 goto error; 553 trigger = on_off->switch_on & on_off->switch_off; 554 flags &= ~(on_off->switch_off ^ trigger); 555 flags |= on_off->switch_on ^ trigger; 556 flags ^= trigger; 557 if (on_off->counter) 558 (*(on_off->counter))++; 559 if (optarg) { 560 if (on_off->param_type == PARAM_LIST) { 561 llist_add_to_end((llist_t **)(on_off->optarg), optarg); 562 } else if (on_off->param_type == PARAM_INT) { 563//TODO: xatoi_positive indirectly pulls in printf machinery 564 *(unsigned*)(on_off->optarg) = xatoi_positive(optarg); 565 } else if (on_off->optarg) { 566 *(char **)(on_off->optarg) = optarg; 567 } 568 } 569 } 570 571 /* check depending requires for given options */ 572 for (on_off = complementary; on_off->opt_char; on_off++) { 573 if (on_off->requires 574 && (flags & on_off->switch_on) 575 && (flags & on_off->requires) == 0 576 ) { 577 goto error; 578 } 579 } 580 if (requires && (flags & requires) == 0) 581 goto error; 582 argc -= optind; 583 if (argc < min_arg || (max_arg >= 0 && argc > max_arg)) 584 goto error; 585 586 option_mask32 = flags; 587 return flags; 588 589 error: 590 if (dont_die_flag != '!') 591 bb_show_usage(); 592 return (int32_t)-1; 593} 594 595uint32_t FAST_FUNC 596getopt32(char **argv, const char *applet_opts, ...) 597{ 598 uint32_t opt; 599 va_list p; 600 601 va_start(p, applet_opts); 602 opt = vgetopt32(argv, applet_opts, NULL, p); 603 va_end(p); 604 return opt; 605} 606 607#if ENABLE_LONG_OPTS 608uint32_t FAST_FUNC 609getopt32long(char **argv, const char *applet_opts, const char *longopts, ...) 610{ 611 uint32_t opt; 612 va_list p; 613 614 va_start(p, longopts); 615 opt = vgetopt32(argv, applet_opts, longopts, p); 616 va_end(p); 617 return opt; 618} 619#endif 620