xref: /openbsd/lib/libc/stdlib/getopt_long.c (revision 91f110e0)
1 /*	$OpenBSD: getopt_long.c,v 1.26 2013/06/08 22:47:56 millert 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 #include <err.h>
53 #include <errno.h>
54 #include <getopt.h>
55 #include <stdlib.h>
56 #include <string.h>
57 
58 int	opterr = 1;		/* if error message should be printed */
59 int	optind = 1;		/* index into parent argv vector */
60 int	optopt = '?';		/* character checked for validity */
61 int	optreset;		/* reset getopt */
62 char    *optarg;		/* argument associated with option */
63 
64 #define PRINT_ERROR	((opterr) && (*options != ':'))
65 
66 #define FLAG_PERMUTE	0x01	/* permute non-options to the end of argv */
67 #define FLAG_ALLARGS	0x02	/* treat non-options as args to option "-1" */
68 #define FLAG_LONGONLY	0x04	/* operate as getopt_long_only */
69 
70 /* return values */
71 #define	BADCH		(int)'?'
72 #define	BADARG		((*options == ':') ? (int)':' : (int)'?')
73 #define	INORDER 	(int)1
74 
75 #define	EMSG		""
76 
77 static int getopt_internal(int, char * const *, const char *,
78 			   const struct option *, int *, int);
79 static int parse_long_options(char * const *, const char *,
80 			      const struct option *, int *, int, int);
81 static int gcd(int, int);
82 static void permute_args(int, int, int, char * const *);
83 
84 static char *place = EMSG; /* option letter processing */
85 
86 /* XXX: set optreset to 1 rather than these two */
87 static int nonopt_start = -1; /* first non option argument (for permute) */
88 static int nonopt_end = -1;   /* first option after non options (for permute) */
89 
90 /* Error messages */
91 static const char recargchar[] = "option requires an argument -- %c";
92 static const char recargstring[] = "option requires an argument -- %s";
93 static const char ambig[] = "ambiguous option -- %.*s";
94 static const char noarg[] = "option doesn't take an argument -- %.*s";
95 static const char illoptchar[] = "unknown option -- %c";
96 static const char illoptstring[] = "unknown option -- %s";
97 
98 /*
99  * Compute the greatest common divisor of a and b.
100  */
101 static int
102 gcd(int a, int b)
103 {
104 	int c;
105 
106 	c = a % b;
107 	while (c != 0) {
108 		a = b;
109 		b = c;
110 		c = a % b;
111 	}
112 
113 	return (b);
114 }
115 
116 /*
117  * Exchange the block from nonopt_start to nonopt_end with the block
118  * from nonopt_end to opt_end (keeping the same order of arguments
119  * in each block).
120  */
121 static void
122 permute_args(int panonopt_start, int panonopt_end, int opt_end,
123 	char * const *nargv)
124 {
125 	int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
126 	char *swap;
127 
128 	/*
129 	 * compute lengths of blocks and number and size of cycles
130 	 */
131 	nnonopts = panonopt_end - panonopt_start;
132 	nopts = opt_end - panonopt_end;
133 	ncycle = gcd(nnonopts, nopts);
134 	cyclelen = (opt_end - panonopt_start) / ncycle;
135 
136 	for (i = 0; i < ncycle; i++) {
137 		cstart = panonopt_end+i;
138 		pos = cstart;
139 		for (j = 0; j < cyclelen; j++) {
140 			if (pos >= panonopt_end)
141 				pos -= nnonopts;
142 			else
143 				pos += nopts;
144 			swap = nargv[pos];
145 			/* LINTED const cast */
146 			((char **) nargv)[pos] = nargv[cstart];
147 			/* LINTED const cast */
148 			((char **)nargv)[cstart] = swap;
149 		}
150 	}
151 }
152 
153 /*
154  * parse_long_options --
155  *	Parse long options in argc/argv argument vector.
156  * Returns -1 if short_too is set and the option does not match long_options.
157  */
158 static int
159 parse_long_options(char * const *nargv, const char *options,
160 	const struct option *long_options, int *idx, int short_too, int flags)
161 {
162 	char *current_argv, *has_equal;
163 	size_t current_argv_len;
164 	int i, match, exact_match, second_partial_match;
165 
166 	current_argv = place;
167 	match = -1;
168 	exact_match = 0;
169 	second_partial_match = 0;
170 
171 	optind++;
172 
173 	if ((has_equal = strchr(current_argv, '=')) != NULL) {
174 		/* argument found (--option=arg) */
175 		current_argv_len = has_equal - current_argv;
176 		has_equal++;
177 	} else
178 		current_argv_len = strlen(current_argv);
179 
180 	for (i = 0; long_options[i].name; i++) {
181 		/* find matching long option */
182 		if (strncmp(current_argv, long_options[i].name,
183 		    current_argv_len))
184 			continue;
185 
186 		if (strlen(long_options[i].name) == current_argv_len) {
187 			/* exact match */
188 			match = i;
189 			exact_match = 1;
190 			break;
191 		}
192 		/*
193 		 * If this is a known short option, don't allow
194 		 * a partial match of a single character.
195 		 */
196 		if (short_too && current_argv_len == 1)
197 			continue;
198 
199 		if (match == -1)	/* first partial match */
200 			match = i;
201 		else if ((flags & FLAG_LONGONLY) ||
202 		    long_options[i].has_arg != long_options[match].has_arg ||
203 		    long_options[i].flag != long_options[match].flag ||
204 		    long_options[i].val != long_options[match].val)
205 			second_partial_match = 1;
206 	}
207 	if (!exact_match && second_partial_match) {
208 		/* ambiguous abbreviation */
209 		if (PRINT_ERROR)
210 			warnx(ambig, (int)current_argv_len, current_argv);
211 		optopt = 0;
212 		return (BADCH);
213 	}
214 	if (match != -1) {		/* option found */
215 		if (long_options[match].has_arg == no_argument
216 		    && has_equal) {
217 			if (PRINT_ERROR)
218 				warnx(noarg, (int)current_argv_len,
219 				     current_argv);
220 			/*
221 			 * XXX: GNU sets optopt to val regardless of flag
222 			 */
223 			if (long_options[match].flag == NULL)
224 				optopt = long_options[match].val;
225 			else
226 				optopt = 0;
227 			return (BADARG);
228 		}
229 		if (long_options[match].has_arg == required_argument ||
230 		    long_options[match].has_arg == optional_argument) {
231 			if (has_equal)
232 				optarg = has_equal;
233 			else if (long_options[match].has_arg ==
234 			    required_argument) {
235 				/*
236 				 * optional argument doesn't use next nargv
237 				 */
238 				optarg = nargv[optind++];
239 			}
240 		}
241 		if ((long_options[match].has_arg == required_argument)
242 		    && (optarg == NULL)) {
243 			/*
244 			 * Missing argument; leading ':' indicates no error
245 			 * should be generated.
246 			 */
247 			if (PRINT_ERROR)
248 				warnx(recargstring,
249 				    current_argv);
250 			/*
251 			 * XXX: GNU sets optopt to val regardless of flag
252 			 */
253 			if (long_options[match].flag == NULL)
254 				optopt = long_options[match].val;
255 			else
256 				optopt = 0;
257 			--optind;
258 			return (BADARG);
259 		}
260 	} else {			/* unknown option */
261 		if (short_too) {
262 			--optind;
263 			return (-1);
264 		}
265 		if (PRINT_ERROR)
266 			warnx(illoptstring, current_argv);
267 		optopt = 0;
268 		return (BADCH);
269 	}
270 	if (idx)
271 		*idx = match;
272 	if (long_options[match].flag) {
273 		*long_options[match].flag = long_options[match].val;
274 		return (0);
275 	} else
276 		return (long_options[match].val);
277 }
278 
279 /*
280  * getopt_internal --
281  *	Parse argc/argv argument vector.  Called by user level routines.
282  */
283 static int
284 getopt_internal(int nargc, char * const *nargv, const char *options,
285 	const struct option *long_options, int *idx, int flags)
286 {
287 	char *oli;				/* option letter list index */
288 	int optchar, short_too;
289 	static int posixly_correct = -1;
290 
291 	if (options == NULL)
292 		return (-1);
293 
294 	/*
295 	 * XXX Some GNU programs (like cvs) set optind to 0 instead of
296 	 * XXX using optreset.  Work around this braindamage.
297 	 */
298 	if (optind == 0)
299 		optind = optreset = 1;
300 
301 	/*
302 	 * Disable GNU extensions if POSIXLY_CORRECT is set or options
303 	 * string begins with a '+'.
304 	 */
305 	if (posixly_correct == -1 || optreset)
306 		posixly_correct = (getenv("POSIXLY_CORRECT") != NULL);
307 	if (*options == '-')
308 		flags |= FLAG_ALLARGS;
309 	else if (posixly_correct || *options == '+')
310 		flags &= ~FLAG_PERMUTE;
311 	if (*options == '+' || *options == '-')
312 		options++;
313 
314 	optarg = NULL;
315 	if (optreset)
316 		nonopt_start = nonopt_end = -1;
317 start:
318 	if (optreset || !*place) {		/* update scanning pointer */
319 		optreset = 0;
320 		if (optind >= nargc) {          /* end of argument vector */
321 			place = EMSG;
322 			if (nonopt_end != -1) {
323 				/* do permutation, if we have to */
324 				permute_args(nonopt_start, nonopt_end,
325 				    optind, nargv);
326 				optind -= nonopt_end - nonopt_start;
327 			}
328 			else if (nonopt_start != -1) {
329 				/*
330 				 * If we skipped non-options, set optind
331 				 * to the first of them.
332 				 */
333 				optind = nonopt_start;
334 			}
335 			nonopt_start = nonopt_end = -1;
336 			return (-1);
337 		}
338 		if (*(place = nargv[optind]) != '-' ||
339 		    (place[1] == '\0' && strchr(options, '-') == NULL)) {
340 			place = EMSG;		/* found non-option */
341 			if (flags & FLAG_ALLARGS) {
342 				/*
343 				 * GNU extension:
344 				 * return non-option as argument to option 1
345 				 */
346 				optarg = nargv[optind++];
347 				return (INORDER);
348 			}
349 			if (!(flags & FLAG_PERMUTE)) {
350 				/*
351 				 * If no permutation wanted, stop parsing
352 				 * at first non-option.
353 				 */
354 				return (-1);
355 			}
356 			/* do permutation */
357 			if (nonopt_start == -1)
358 				nonopt_start = optind;
359 			else if (nonopt_end != -1) {
360 				permute_args(nonopt_start, nonopt_end,
361 				    optind, nargv);
362 				nonopt_start = optind -
363 				    (nonopt_end - nonopt_start);
364 				nonopt_end = -1;
365 			}
366 			optind++;
367 			/* process next argument */
368 			goto start;
369 		}
370 		if (nonopt_start != -1 && nonopt_end == -1)
371 			nonopt_end = optind;
372 
373 		/*
374 		 * If we have "-" do nothing, if "--" we are done.
375 		 */
376 		if (place[1] != '\0' && *++place == '-' && place[1] == '\0') {
377 			optind++;
378 			place = EMSG;
379 			/*
380 			 * We found an option (--), so if we skipped
381 			 * non-options, we have to permute.
382 			 */
383 			if (nonopt_end != -1) {
384 				permute_args(nonopt_start, nonopt_end,
385 				    optind, nargv);
386 				optind -= nonopt_end - nonopt_start;
387 			}
388 			nonopt_start = nonopt_end = -1;
389 			return (-1);
390 		}
391 	}
392 
393 	/*
394 	 * Check long options if:
395 	 *  1) we were passed some
396 	 *  2) the arg is not just "-"
397 	 *  3) either the arg starts with -- we are getopt_long_only()
398 	 */
399 	if (long_options != NULL && place != nargv[optind] &&
400 	    (*place == '-' || (flags & FLAG_LONGONLY))) {
401 		short_too = 0;
402 		if (*place == '-')
403 			place++;		/* --foo long option */
404 		else if (*place != ':' && strchr(options, *place) != NULL)
405 			short_too = 1;		/* could be short option too */
406 
407 		optchar = parse_long_options(nargv, options, long_options,
408 		    idx, short_too, flags);
409 		if (optchar != -1) {
410 			place = EMSG;
411 			return (optchar);
412 		}
413 	}
414 
415 	if ((optchar = (int)*place++) == (int)':' ||
416 	    (optchar == (int)'-' && *place != '\0') ||
417 	    (oli = strchr(options, optchar)) == NULL) {
418 		/*
419 		 * If the user specified "-" and  '-' isn't listed in
420 		 * options, return -1 (non-option) as per POSIX.
421 		 * Otherwise, it is an unknown option character (or ':').
422 		 */
423 		if (optchar == (int)'-' && *place == '\0')
424 			return (-1);
425 		if (!*place)
426 			++optind;
427 		if (PRINT_ERROR)
428 			warnx(illoptchar, optchar);
429 		optopt = optchar;
430 		return (BADCH);
431 	}
432 	if (long_options != NULL && optchar == 'W' && oli[1] == ';') {
433 		/* -W long-option */
434 		if (*place)			/* no space */
435 			/* NOTHING */;
436 		else if (++optind >= nargc) {	/* no arg */
437 			place = EMSG;
438 			if (PRINT_ERROR)
439 				warnx(recargchar, optchar);
440 			optopt = optchar;
441 			return (BADARG);
442 		} else				/* white space */
443 			place = nargv[optind];
444 		optchar = parse_long_options(nargv, options, long_options,
445 		    idx, 0, flags);
446 		place = EMSG;
447 		return (optchar);
448 	}
449 	if (*++oli != ':') {			/* doesn't take argument */
450 		if (!*place)
451 			++optind;
452 	} else {				/* takes (optional) argument */
453 		optarg = NULL;
454 		if (*place)			/* no white space */
455 			optarg = place;
456 		else if (oli[1] != ':') {	/* arg not optional */
457 			if (++optind >= nargc) {	/* no arg */
458 				place = EMSG;
459 				if (PRINT_ERROR)
460 					warnx(recargchar, optchar);
461 				optopt = optchar;
462 				return (BADARG);
463 			} else
464 				optarg = nargv[optind];
465 		}
466 		place = EMSG;
467 		++optind;
468 	}
469 	/* dump back option letter */
470 	return (optchar);
471 }
472 
473 /*
474  * getopt --
475  *	Parse argc/argv argument vector.
476  *
477  * [eventually this will replace the BSD getopt]
478  */
479 int
480 getopt(int nargc, char * const *nargv, const char *options)
481 {
482 
483 	/*
484 	 * We don't pass FLAG_PERMUTE to getopt_internal() since
485 	 * the BSD getopt(3) (unlike GNU) has never done this.
486 	 *
487 	 * Furthermore, since many privileged programs call getopt()
488 	 * before dropping privileges it makes sense to keep things
489 	 * as simple (and bug-free) as possible.
490 	 */
491 	return (getopt_internal(nargc, nargv, options, NULL, NULL, 0));
492 }
493 
494 /*
495  * getopt_long --
496  *	Parse argc/argv argument vector.
497  */
498 int
499 getopt_long(int nargc, char * const *nargv, const char *options,
500     const struct option *long_options, int *idx)
501 {
502 
503 	return (getopt_internal(nargc, nargv, options, long_options, idx,
504 	    FLAG_PERMUTE));
505 }
506 
507 /*
508  * getopt_long_only --
509  *	Parse argc/argv argument vector.
510  */
511 int
512 getopt_long_only(int nargc, char * const *nargv, const char *options,
513     const struct option *long_options, int *idx)
514 {
515 
516 	return (getopt_internal(nargc, nargv, options, long_options, idx,
517 	    FLAG_PERMUTE|FLAG_LONGONLY));
518 }
519