xref: /freebsd/contrib/tcpdump/missing/getopt_long.c (revision cc426dd31990b8b50b210efc450e404596548ca1)
1 /*	$OpenBSD: getopt_long.c,v 1.22 2006/10/04 21:29:04 jmc Exp $	*/
2 /*	$NetBSD: getopt_long.c,v 1.15 2002/01/31 22:43:40 tv Exp $	*/
3 
4 /*
5  * Copyright (c) 2002 Todd C. Miller <Todd.Miller@courtesan.com>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  *
19  * Sponsored in part by the Defense Advanced Research Projects
20  * Agency (DARPA) and Air Force Research Laboratory, Air Force
21  * Materiel Command, USAF, under agreement number F39502-99-1-0512.
22  */
23 /*-
24  * Copyright (c) 2000 The NetBSD Foundation, Inc.
25  * All rights reserved.
26  *
27  * This code is derived from software contributed to The NetBSD Foundation
28  * by Dieter Baron and Thomas Klausner.
29  *
30  * Redistribution and use in source and binary forms, with or without
31  * modification, are permitted provided that the following conditions
32  * are met:
33  * 1. Redistributions of source code must retain the above copyright
34  *    notice, this list of conditions and the following disclaimer.
35  * 2. Redistributions in binary form must reproduce the above copyright
36  *    notice, this list of conditions and the following disclaimer in the
37  *    documentation and/or other materials provided with the distribution.
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
40  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
41  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
43  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
44  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
45  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
46  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
47  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
49  * POSSIBILITY OF SUCH DAMAGE.
50  */
51 
52 
53 #include <errno.h>
54 #include "getopt_long.h"
55 #include <stdlib.h>
56 #include <stdio.h>
57 #include <string.h>
58 #include <stdarg.h>
59 
60 #define GNU_COMPATIBLE		/* Be more compatible, configure's use us! */
61 
62 #define PRINT_ERROR	((opterr) && (*options != ':'))
63 
64 #define FLAG_PERMUTE	0x01	/* permute non-options to the end of argv */
65 #define FLAG_ALLARGS	0x02	/* treat non-options as args to option "-1" */
66 #define FLAG_LONGONLY	0x04	/* operate as getopt_long_only */
67 
68 /* return values */
69 #define	BADCH		(int)'?'
70 #define	BADARG		((*options == ':') ? (int)':' : (int)'?')
71 #define	INORDER 	(int)1
72 
73 #define	EMSG		""
74 
75 #ifdef GNU_COMPATIBLE
76 #define NO_PREFIX	(-1)
77 #define D_PREFIX	0
78 #define DD_PREFIX	1
79 #define W_PREFIX	2
80 #endif
81 
82 char *optarg;
83 int optind, opterr = 1, optopt;
84 
85 static int getopt_internal(int, char * const *, const char *,
86 			   const struct option *, int *, int);
87 static int parse_long_options(char * const *, const char *,
88 			      const struct option *, int *, int, int);
89 static int gcd(int, int);
90 static void permute_args(int, int, int, char * const *);
91 
92 static const char *place = EMSG; /* option letter processing */
93 
94 static int nonopt_start = -1; /* first non option argument (for permute) */
95 static int nonopt_end = -1;   /* first option after non options (for permute) */
96 
97 /* Error messages */
98 static const char recargchar[] = "option requires an argument -- %c";
99 static const char illoptchar[] = "illegal option -- %c"; /* From P1003.2 */
100 #ifdef GNU_COMPATIBLE
101 static int dash_prefix = NO_PREFIX;
102 static const char gnuoptchar[] = "invalid option -- %c";
103 
104 static const char recargstring[] = "option `%s%s' requires an argument";
105 static const char ambig[] = "option `%s%.*s' is ambiguous";
106 static const char noarg[] = "option `%s%.*s' doesn't allow an argument";
107 static const char illoptstring[] = "unrecognized option `%s%s'";
108 #else
109 static const char recargstring[] = "option requires an argument -- %s";
110 static const char ambig[] = "ambiguous option -- %.*s";
111 static const char noarg[] = "option doesn't take an argument -- %.*s";
112 static const char illoptstring[] = "unknown option -- %s";
113 #endif
114 
115 /*
116  * Compute the greatest common divisor of a and b.
117  */
118 static int
119 gcd(int a, int b)
120 {
121 	int c;
122 
123 	c = a % b;
124 	while (c != 0) {
125 		a = b;
126 		b = c;
127 		c = a % b;
128 	}
129 
130 	return (b);
131 }
132 
133 /*
134  * Exchange the block from nonopt_start to nonopt_end with the block
135  * from nonopt_end to opt_end (keeping the same order of arguments
136  * in each block).
137  */
138 static void
139 permute_args(int panonopt_start, int panonopt_end, int opt_end,
140 	char * const *nargv)
141 {
142 	int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
143 	char *swap;
144 
145 	/*
146 	 * compute lengths of blocks and number and size of cycles
147 	 */
148 	nnonopts = panonopt_end - panonopt_start;
149 	nopts = opt_end - panonopt_end;
150 	ncycle = gcd(nnonopts, nopts);
151 	cyclelen = (opt_end - panonopt_start) / ncycle;
152 
153 	for (i = 0; i < ncycle; i++) {
154 		cstart = panonopt_end+i;
155 		pos = cstart;
156 		for (j = 0; j < cyclelen; j++) {
157 			if (pos >= panonopt_end)
158 				pos -= nnonopts;
159 			else
160 				pos += nopts;
161 			swap = nargv[pos];
162 			/* LINTED const cast */
163 			((char **) nargv)[pos] = nargv[cstart];
164 			/* LINTED const cast */
165 			((char **)nargv)[cstart] = swap;
166 		}
167 	}
168 }
169 
170 static void
171 warnx(const char *fmt, ...)
172 {
173 	extern char *program_name;
174 	va_list ap;
175 
176 	va_start(ap, fmt);
177 	fprintf(stderr, "%s: ", program_name);
178 	vfprintf(stderr, fmt, ap);
179 	fprintf(stderr, "\n");
180 	va_end(ap);
181 }
182 
183 /*
184  * parse_long_options --
185  *	Parse long options in argc/argv argument vector.
186  * Returns -1 if short_too is set and the option does not match long_options.
187  */
188 static int
189 parse_long_options(char * const *nargv, const char *options,
190 	const struct option *long_options, int *idx, int short_too, int flags)
191 {
192 	const char *current_argv, *has_equal;
193 #ifdef GNU_COMPATIBLE
194 	const char *current_dash;
195 #endif
196 	size_t current_argv_len;
197 	int i, match, exact_match, second_partial_match;
198 
199 	current_argv = place;
200 #ifdef GNU_COMPATIBLE
201 	switch (dash_prefix) {
202 		case D_PREFIX:
203 			current_dash = "-";
204 			break;
205 		case DD_PREFIX:
206 			current_dash = "--";
207 			break;
208 		case W_PREFIX:
209 			current_dash = "-W ";
210 			break;
211 		default:
212 			current_dash = "";
213 			break;
214 	}
215 #endif
216 	match = -1;
217 	exact_match = 0;
218 	second_partial_match = 0;
219 
220 	optind++;
221 
222 	if ((has_equal = strchr(current_argv, '=')) != NULL) {
223 		/* argument found (--option=arg) */
224 		current_argv_len = has_equal - current_argv;
225 		has_equal++;
226 	} else
227 		current_argv_len = strlen(current_argv);
228 
229 	for (i = 0; long_options[i].name; i++) {
230 		/* find matching long option */
231 		if (strncmp(current_argv, long_options[i].name,
232 		    current_argv_len))
233 			continue;
234 
235 		if (strlen(long_options[i].name) == current_argv_len) {
236 			/* exact match */
237 			match = i;
238 			exact_match = 1;
239 			break;
240 		}
241 		/*
242 		 * If this is a known short option, don't allow
243 		 * a partial match of a single character.
244 		 */
245 		if (short_too && current_argv_len == 1)
246 			continue;
247 
248 		if (match == -1)        /* first partial match */
249 			match = i;
250 		else if ((flags & FLAG_LONGONLY) ||
251 			 long_options[i].has_arg !=
252 			     long_options[match].has_arg ||
253 			 long_options[i].flag != long_options[match].flag ||
254 			 long_options[i].val != long_options[match].val)
255 			second_partial_match = 1;
256 	}
257 	if (!exact_match && second_partial_match) {
258 		/* ambiguous abbreviation */
259 		if (PRINT_ERROR)
260 			warnx(ambig,
261 #ifdef GNU_COMPATIBLE
262 			     current_dash,
263 #endif
264 			     (int)current_argv_len,
265 			     current_argv);
266 		optopt = 0;
267 		return (BADCH);
268 	}
269 	if (match != -1) {		/* option found */
270 		if (long_options[match].has_arg == no_argument
271 		    && has_equal) {
272 			if (PRINT_ERROR)
273 				warnx(noarg,
274 #ifdef GNU_COMPATIBLE
275 				     current_dash,
276 #endif
277 				     (int)current_argv_len,
278 				     current_argv);
279 			/*
280 			 * XXX: GNU sets optopt to val regardless of flag
281 			 */
282 			if (long_options[match].flag == NULL)
283 				optopt = long_options[match].val;
284 			else
285 				optopt = 0;
286 #ifdef GNU_COMPATIBLE
287 			return (BADCH);
288 #else
289 			return (BADARG);
290 #endif
291 		}
292 		if (long_options[match].has_arg == required_argument ||
293 		    long_options[match].has_arg == optional_argument) {
294 			if (has_equal)
295 				optarg = (char *)has_equal;
296 			else if (long_options[match].has_arg ==
297 			    required_argument) {
298 				/*
299 				 * optional argument doesn't use next nargv
300 				 */
301 				optarg = nargv[optind++];
302 			}
303 		}
304 		if ((long_options[match].has_arg == required_argument)
305 		    && (optarg == NULL)) {
306 			/*
307 			 * Missing argument; leading ':' indicates no error
308 			 * should be generated.
309 			 */
310 			if (PRINT_ERROR)
311 				warnx(recargstring,
312 #ifdef GNU_COMPATIBLE
313 				    current_dash,
314 #endif
315 				    current_argv);
316 			/*
317 			 * XXX: GNU sets optopt to val regardless of flag
318 			 */
319 			if (long_options[match].flag == NULL)
320 				optopt = long_options[match].val;
321 			else
322 				optopt = 0;
323 			--optind;
324 			return (BADARG);
325 		}
326 	} else {			/* unknown option */
327 		if (short_too) {
328 			--optind;
329 			return (-1);
330 		}
331 		if (PRINT_ERROR)
332 			warnx(illoptstring,
333 #ifdef GNU_COMPATIBLE
334 			      current_dash,
335 #endif
336 			      current_argv);
337 		optopt = 0;
338 		return (BADCH);
339 	}
340 	if (idx)
341 		*idx = match;
342 	if (long_options[match].flag) {
343 		*long_options[match].flag = long_options[match].val;
344 		return (0);
345 	} else
346 		return (long_options[match].val);
347 }
348 
349 /*
350  * getopt_internal --
351  *	Parse argc/argv argument vector.  Called by user level routines.
352  */
353 static int
354 getopt_internal(int nargc, char * const *nargv, const char *options,
355 	const struct option *long_options, int *idx, int flags)
356 {
357 	char *oli;				/* option letter list index */
358 	int optchar, short_too;
359 	int posixly_correct;	/* no static, can be changed on the fly */
360 
361 	if (options == NULL)
362 		return (-1);
363 
364 	/*
365 	 * Disable GNU extensions if POSIXLY_CORRECT is set or options
366 	 * string begins with a '+'.
367 	 */
368 	posixly_correct = (getenv("POSIXLY_CORRECT") != NULL);
369 #ifdef GNU_COMPATIBLE
370 	if (*options == '-')
371 		flags |= FLAG_ALLARGS;
372 	else if (posixly_correct || *options == '+')
373 		flags &= ~FLAG_PERMUTE;
374 #else
375 	if (posixly_correct || *options == '+')
376 		flags &= ~FLAG_PERMUTE;
377 	else if (*options == '-')
378 		flags |= FLAG_ALLARGS;
379 #endif
380 	if (*options == '+' || *options == '-')
381 		options++;
382 
383 	/*
384 	 * XXX Some GNU programs (like cvs) set optind to 0 instead of
385 	 * XXX using optreset.  Work around this braindamage.
386 	 */
387 	if (optind == 0)
388 		optind = 1;
389 
390 	optarg = NULL;
391 start:
392 	if (!*place) {				/* update scanning pointer */
393 		if (optind >= nargc) {          /* end of argument vector */
394 			place = EMSG;
395 			if (nonopt_end != -1) {
396 				/* do permutation, if we have to */
397 				permute_args(nonopt_start, nonopt_end,
398 				    optind, nargv);
399 				optind -= nonopt_end - nonopt_start;
400 			}
401 			else if (nonopt_start != -1) {
402 				/*
403 				 * If we skipped non-options, set optind
404 				 * to the first of them.
405 				 */
406 				optind = nonopt_start;
407 			}
408 			nonopt_start = nonopt_end = -1;
409 			return (-1);
410 		}
411 		if (*(place = nargv[optind]) != '-' ||
412 #ifdef GNU_COMPATIBLE
413 		    place[1] == '\0') {
414 #else
415 		    (place[1] == '\0' && strchr(options, '-') == NULL)) {
416 #endif
417 			place = EMSG;		/* found non-option */
418 			if (flags & FLAG_ALLARGS) {
419 				/*
420 				 * GNU extension:
421 				 * return non-option as argument to option 1
422 				 */
423 				optarg = nargv[optind++];
424 				return (INORDER);
425 			}
426 			if (!(flags & FLAG_PERMUTE)) {
427 				/*
428 				 * If no permutation wanted, stop parsing
429 				 * at first non-option.
430 				 */
431 				return (-1);
432 			}
433 			/* do permutation */
434 			if (nonopt_start == -1)
435 				nonopt_start = optind;
436 			else if (nonopt_end != -1) {
437 				permute_args(nonopt_start, nonopt_end,
438 				    optind, nargv);
439 				nonopt_start = optind -
440 				    (nonopt_end - nonopt_start);
441 				nonopt_end = -1;
442 			}
443 			optind++;
444 			/* process next argument */
445 			goto start;
446 		}
447 		if (nonopt_start != -1 && nonopt_end == -1)
448 			nonopt_end = optind;
449 
450 		/*
451 		 * If we have "-" do nothing, if "--" we are done.
452 		 */
453 		if (place[1] != '\0' && *++place == '-' && place[1] == '\0') {
454 			optind++;
455 			place = EMSG;
456 			/*
457 			 * We found an option (--), so if we skipped
458 			 * non-options, we have to permute.
459 			 */
460 			if (nonopt_end != -1) {
461 				permute_args(nonopt_start, nonopt_end,
462 				    optind, nargv);
463 				optind -= nonopt_end - nonopt_start;
464 			}
465 			nonopt_start = nonopt_end = -1;
466 			return (-1);
467 		}
468 	}
469 
470 	/*
471 	 * Check long options if:
472 	 *  1) we were passed some
473 	 *  2) the arg is not just "-"
474 	 *  3) either the arg starts with -- we are getopt_long_only()
475 	 */
476 	if (long_options != NULL && place != nargv[optind] &&
477 	    (*place == '-' || (flags & FLAG_LONGONLY))) {
478 		short_too = 0;
479 #ifdef GNU_COMPATIBLE
480 		dash_prefix = D_PREFIX;
481 #endif
482 		if (*place == '-') {
483 			place++;		/* --foo long option */
484 #ifdef GNU_COMPATIBLE
485 			dash_prefix = DD_PREFIX;
486 #endif
487 		} else if (*place != ':' && strchr(options, *place) != NULL)
488 			short_too = 1;		/* could be short option too */
489 
490 		optchar = parse_long_options(nargv, options, long_options,
491 		    idx, short_too, flags);
492 		if (optchar != -1) {
493 			place = EMSG;
494 			return (optchar);
495 		}
496 	}
497 
498 	if ((optchar = (int)*place++) == (int)':' ||
499 	    (optchar == (int)'-' && *place != '\0') ||
500 	    (oli = strchr(options, optchar)) == NULL) {
501 		/*
502 		 * If the user specified "-" and  '-' isn't listed in
503 		 * options, return -1 (non-option) as per POSIX.
504 		 * Otherwise, it is an unknown option character (or ':').
505 		 */
506 		if (optchar == (int)'-' && *place == '\0')
507 			return (-1);
508 		if (!*place)
509 			++optind;
510 #ifdef GNU_COMPATIBLE
511 		if (PRINT_ERROR)
512 			warnx(posixly_correct ? illoptchar : gnuoptchar,
513 			      optchar);
514 #else
515 		if (PRINT_ERROR)
516 			warnx(illoptchar, optchar);
517 #endif
518 		optopt = optchar;
519 		return (BADCH);
520 	}
521 	if (long_options != NULL && optchar == 'W' && oli[1] == ';') {
522 		/* -W long-option */
523 		if (*place)			/* no space */
524 			/* NOTHING */;
525 		else if (++optind >= nargc) {	/* no arg */
526 			place = EMSG;
527 			if (PRINT_ERROR)
528 				warnx(recargchar, optchar);
529 			optopt = optchar;
530 			return (BADARG);
531 		} else				/* white space */
532 			place = nargv[optind];
533 #ifdef GNU_COMPATIBLE
534 		dash_prefix = W_PREFIX;
535 #endif
536 		optchar = parse_long_options(nargv, options, long_options,
537 		    idx, 0, flags);
538 		place = EMSG;
539 		return (optchar);
540 	}
541 	if (*++oli != ':') {			/* doesn't take argument */
542 		if (!*place)
543 			++optind;
544 	} else {				/* takes (optional) argument */
545 		optarg = NULL;
546 		if (*place)			/* no white space */
547 			optarg = (char *)place;
548 		else if (oli[1] != ':') {	/* arg not optional */
549 			if (++optind >= nargc) {	/* no arg */
550 				place = EMSG;
551 				if (PRINT_ERROR)
552 					warnx(recargchar, optchar);
553 				optopt = optchar;
554 				return (BADARG);
555 			} else
556 				optarg = nargv[optind];
557 		}
558 		place = EMSG;
559 		++optind;
560 	}
561 	/* dump back option letter */
562 	return (optchar);
563 }
564 
565 #ifdef REPLACE_GETOPT
566 /*
567  * getopt --
568  *	Parse argc/argv argument vector.
569  *
570  * [eventually this will replace the BSD getopt]
571  */
572 int
573 getopt(int nargc, char * const *nargv, const char *options)
574 {
575 
576 	/*
577 	 * We don't pass FLAG_PERMUTE to getopt_internal() since
578 	 * the BSD getopt(3) (unlike GNU) has never done this.
579 	 *
580 	 * Furthermore, since many privileged programs call getopt()
581 	 * before dropping privileges it makes sense to keep things
582 	 * as simple (and bug-free) as possible.
583 	 */
584 	return (getopt_internal(nargc, nargv, options, NULL, NULL, 0));
585 }
586 #endif /* REPLACE_GETOPT */
587 
588 /*
589  * getopt_long --
590  *	Parse argc/argv argument vector.
591  */
592 int
593 getopt_long(int nargc, char * const *nargv, const char *options,
594 	const struct option *long_options, int *idx)
595 {
596 
597 	return (getopt_internal(nargc, nargv, options, long_options, idx,
598 	    FLAG_PERMUTE));
599 }
600 
601 /*
602  * getopt_long_only --
603  *	Parse argc/argv argument vector.
604  */
605 int
606 getopt_long_only(int nargc, char * const *nargv, const char *options,
607 	const struct option *long_options, int *idx)
608 {
609 
610 	return (getopt_internal(nargc, nargv, options, long_options, idx,
611 	    FLAG_PERMUTE|FLAG_LONGONLY));
612 }
613