xref: /openbsd-src/lib/libc/stdlib/getopt_long.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: getopt_long.c,v 1.23 2007/10/31 12:34:57 chl 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 #define	REPLACE_GETOPT		/* use this getopt as the system getopt(3) */
59 
60 #ifdef REPLACE_GETOPT
61 int	opterr = 1;		/* if error message should be printed */
62 int	optind = 1;		/* index into parent argv vector */
63 int	optopt = '?';		/* character checked for validity */
64 int	optreset;		/* reset getopt */
65 char    *optarg;		/* argument associated with option */
66 #endif
67 
68 #define PRINT_ERROR	((opterr) && (*options != ':'))
69 
70 #define FLAG_PERMUTE	0x01	/* permute non-options to the end of argv */
71 #define FLAG_ALLARGS	0x02	/* treat non-options as args to option "-1" */
72 #define FLAG_LONGONLY	0x04	/* operate as getopt_long_only */
73 
74 /* return values */
75 #define	BADCH		(int)'?'
76 #define	BADARG		((*options == ':') ? (int)':' : (int)'?')
77 #define	INORDER 	(int)1
78 
79 #define	EMSG		""
80 
81 static int getopt_internal(int, char * const *, const char *,
82 			   const struct option *, int *, int);
83 static int parse_long_options(char * const *, const char *,
84 			      const struct option *, int *, int);
85 static int gcd(int, int);
86 static void permute_args(int, int, int, char * const *);
87 
88 static char *place = EMSG; /* option letter processing */
89 
90 /* XXX: set optreset to 1 rather than these two */
91 static int nonopt_start = -1; /* first non option argument (for permute) */
92 static int nonopt_end = -1;   /* first option after non options (for permute) */
93 
94 /* Error messages */
95 static const char recargchar[] = "option requires an argument -- %c";
96 static const char recargstring[] = "option requires an argument -- %s";
97 static const char ambig[] = "ambiguous option -- %.*s";
98 static const char noarg[] = "option doesn't take an argument -- %.*s";
99 static const char illoptchar[] = "unknown option -- %c";
100 static const char illoptstring[] = "unknown option -- %s";
101 
102 /*
103  * Compute the greatest common divisor of a and b.
104  */
105 static int
106 gcd(int a, int b)
107 {
108 	int c;
109 
110 	c = a % b;
111 	while (c != 0) {
112 		a = b;
113 		b = c;
114 		c = a % b;
115 	}
116 
117 	return (b);
118 }
119 
120 /*
121  * Exchange the block from nonopt_start to nonopt_end with the block
122  * from nonopt_end to opt_end (keeping the same order of arguments
123  * in each block).
124  */
125 static void
126 permute_args(int panonopt_start, int panonopt_end, int opt_end,
127 	char * const *nargv)
128 {
129 	int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
130 	char *swap;
131 
132 	/*
133 	 * compute lengths of blocks and number and size of cycles
134 	 */
135 	nnonopts = panonopt_end - panonopt_start;
136 	nopts = opt_end - panonopt_end;
137 	ncycle = gcd(nnonopts, nopts);
138 	cyclelen = (opt_end - panonopt_start) / ncycle;
139 
140 	for (i = 0; i < ncycle; i++) {
141 		cstart = panonopt_end+i;
142 		pos = cstart;
143 		for (j = 0; j < cyclelen; j++) {
144 			if (pos >= panonopt_end)
145 				pos -= nnonopts;
146 			else
147 				pos += nopts;
148 			swap = nargv[pos];
149 			/* LINTED const cast */
150 			((char **) nargv)[pos] = nargv[cstart];
151 			/* LINTED const cast */
152 			((char **)nargv)[cstart] = swap;
153 		}
154 	}
155 }
156 
157 /*
158  * parse_long_options --
159  *	Parse long options in argc/argv argument vector.
160  * Returns -1 if short_too is set and the option does not match long_options.
161  */
162 static int
163 parse_long_options(char * const *nargv, const char *options,
164 	const struct option *long_options, int *idx, int short_too)
165 {
166 	char *current_argv, *has_equal;
167 	size_t current_argv_len;
168 	int i, match;
169 
170 	current_argv = place;
171 	match = -1;
172 
173 	optind++;
174 
175 	if ((has_equal = strchr(current_argv, '=')) != NULL) {
176 		/* argument found (--option=arg) */
177 		current_argv_len = has_equal - current_argv;
178 		has_equal++;
179 	} else
180 		current_argv_len = strlen(current_argv);
181 
182 	for (i = 0; long_options[i].name; i++) {
183 		/* find matching long option */
184 		if (strncmp(current_argv, long_options[i].name,
185 		    current_argv_len))
186 			continue;
187 
188 		if (strlen(long_options[i].name) == current_argv_len) {
189 			/* exact match */
190 			match = i;
191 			break;
192 		}
193 		/*
194 		 * If this is a known short option, don't allow
195 		 * a partial match of a single character.
196 		 */
197 		if (short_too && current_argv_len == 1)
198 			continue;
199 
200 		if (match == -1)	/* partial match */
201 			match = i;
202 		else {
203 			/* ambiguous abbreviation */
204 			if (PRINT_ERROR)
205 				warnx(ambig, (int)current_argv_len,
206 				     current_argv);
207 			optopt = 0;
208 			return (BADCH);
209 		}
210 	}
211 	if (match != -1) {		/* option found */
212 		if (long_options[match].has_arg == no_argument
213 		    && has_equal) {
214 			if (PRINT_ERROR)
215 				warnx(noarg, (int)current_argv_len,
216 				     current_argv);
217 			/*
218 			 * XXX: GNU sets optopt to val regardless of flag
219 			 */
220 			if (long_options[match].flag == NULL)
221 				optopt = long_options[match].val;
222 			else
223 				optopt = 0;
224 			return (BADARG);
225 		}
226 		if (long_options[match].has_arg == required_argument ||
227 		    long_options[match].has_arg == optional_argument) {
228 			if (has_equal)
229 				optarg = has_equal;
230 			else if (long_options[match].has_arg ==
231 			    required_argument) {
232 				/*
233 				 * optional argument doesn't use next nargv
234 				 */
235 				optarg = nargv[optind++];
236 			}
237 		}
238 		if ((long_options[match].has_arg == required_argument)
239 		    && (optarg == NULL)) {
240 			/*
241 			 * Missing argument; leading ':' indicates no error
242 			 * should be generated.
243 			 */
244 			if (PRINT_ERROR)
245 				warnx(recargstring,
246 				    current_argv);
247 			/*
248 			 * XXX: GNU sets optopt to val regardless of flag
249 			 */
250 			if (long_options[match].flag == NULL)
251 				optopt = long_options[match].val;
252 			else
253 				optopt = 0;
254 			--optind;
255 			return (BADARG);
256 		}
257 	} else {			/* unknown option */
258 		if (short_too) {
259 			--optind;
260 			return (-1);
261 		}
262 		if (PRINT_ERROR)
263 			warnx(illoptstring, current_argv);
264 		optopt = 0;
265 		return (BADCH);
266 	}
267 	if (idx)
268 		*idx = match;
269 	if (long_options[match].flag) {
270 		*long_options[match].flag = long_options[match].val;
271 		return (0);
272 	} else
273 		return (long_options[match].val);
274 }
275 
276 /*
277  * getopt_internal --
278  *	Parse argc/argv argument vector.  Called by user level routines.
279  */
280 static int
281 getopt_internal(int nargc, char * const *nargv, const char *options,
282 	const struct option *long_options, int *idx, int flags)
283 {
284 	char *oli;				/* option letter list index */
285 	int optchar, short_too;
286 	static int posixly_correct = -1;
287 
288 	if (options == NULL)
289 		return (-1);
290 
291 	/*
292 	 * Disable GNU extensions if POSIXLY_CORRECT is set or options
293 	 * string begins with a '+'.
294 	 */
295 	if (posixly_correct == -1)
296 		posixly_correct = (getenv("POSIXLY_CORRECT") != NULL);
297 	if (posixly_correct || *options == '+')
298 		flags &= ~FLAG_PERMUTE;
299 	else if (*options == '-')
300 		flags |= FLAG_ALLARGS;
301 	if (*options == '+' || *options == '-')
302 		options++;
303 
304 	/*
305 	 * XXX Some GNU programs (like cvs) set optind to 0 instead of
306 	 * XXX using optreset.  Work around this braindamage.
307 	 */
308 	if (optind == 0)
309 		optind = optreset = 1;
310 
311 	optarg = NULL;
312 	if (optreset)
313 		nonopt_start = nonopt_end = -1;
314 start:
315 	if (optreset || !*place) {		/* update scanning pointer */
316 		optreset = 0;
317 		if (optind >= nargc) {          /* end of argument vector */
318 			place = EMSG;
319 			if (nonopt_end != -1) {
320 				/* do permutation, if we have to */
321 				permute_args(nonopt_start, nonopt_end,
322 				    optind, nargv);
323 				optind -= nonopt_end - nonopt_start;
324 			}
325 			else if (nonopt_start != -1) {
326 				/*
327 				 * If we skipped non-options, set optind
328 				 * to the first of them.
329 				 */
330 				optind = nonopt_start;
331 			}
332 			nonopt_start = nonopt_end = -1;
333 			return (-1);
334 		}
335 		if (*(place = nargv[optind]) != '-' ||
336 		    (place[1] == '\0' && strchr(options, '-') == NULL)) {
337 			place = EMSG;		/* found non-option */
338 			if (flags & FLAG_ALLARGS) {
339 				/*
340 				 * GNU extension:
341 				 * return non-option as argument to option 1
342 				 */
343 				optarg = nargv[optind++];
344 				return (INORDER);
345 			}
346 			if (!(flags & FLAG_PERMUTE)) {
347 				/*
348 				 * If no permutation wanted, stop parsing
349 				 * at first non-option.
350 				 */
351 				return (-1);
352 			}
353 			/* do permutation */
354 			if (nonopt_start == -1)
355 				nonopt_start = optind;
356 			else if (nonopt_end != -1) {
357 				permute_args(nonopt_start, nonopt_end,
358 				    optind, nargv);
359 				nonopt_start = optind -
360 				    (nonopt_end - nonopt_start);
361 				nonopt_end = -1;
362 			}
363 			optind++;
364 			/* process next argument */
365 			goto start;
366 		}
367 		if (nonopt_start != -1 && nonopt_end == -1)
368 			nonopt_end = optind;
369 
370 		/*
371 		 * If we have "-" do nothing, if "--" we are done.
372 		 */
373 		if (place[1] != '\0' && *++place == '-' && place[1] == '\0') {
374 			optind++;
375 			place = EMSG;
376 			/*
377 			 * We found an option (--), so if we skipped
378 			 * non-options, we have to permute.
379 			 */
380 			if (nonopt_end != -1) {
381 				permute_args(nonopt_start, nonopt_end,
382 				    optind, nargv);
383 				optind -= nonopt_end - nonopt_start;
384 			}
385 			nonopt_start = nonopt_end = -1;
386 			return (-1);
387 		}
388 	}
389 
390 	/*
391 	 * Check long options if:
392 	 *  1) we were passed some
393 	 *  2) the arg is not just "-"
394 	 *  3) either the arg starts with -- we are getopt_long_only()
395 	 */
396 	if (long_options != NULL && place != nargv[optind] &&
397 	    (*place == '-' || (flags & FLAG_LONGONLY))) {
398 		short_too = 0;
399 		if (*place == '-')
400 			place++;		/* --foo long option */
401 		else if (*place != ':' && strchr(options, *place) != NULL)
402 			short_too = 1;		/* could be short option too */
403 
404 		optchar = parse_long_options(nargv, options, long_options,
405 		    idx, short_too);
406 		if (optchar != -1) {
407 			place = EMSG;
408 			return (optchar);
409 		}
410 	}
411 
412 	if ((optchar = (int)*place++) == (int)':' ||
413 	    (optchar == (int)'-' && *place != '\0') ||
414 	    (oli = strchr(options, optchar)) == NULL) {
415 		/*
416 		 * If the user specified "-" and  '-' isn't listed in
417 		 * options, return -1 (non-option) as per POSIX.
418 		 * Otherwise, it is an unknown option character (or ':').
419 		 */
420 		if (optchar == (int)'-' && *place == '\0')
421 			return (-1);
422 		if (!*place)
423 			++optind;
424 		if (PRINT_ERROR)
425 			warnx(illoptchar, optchar);
426 		optopt = optchar;
427 		return (BADCH);
428 	}
429 	if (long_options != NULL && optchar == 'W' && oli[1] == ';') {
430 		/* -W long-option */
431 		if (*place)			/* no space */
432 			/* NOTHING */;
433 		else if (++optind >= nargc) {	/* no arg */
434 			place = EMSG;
435 			if (PRINT_ERROR)
436 				warnx(recargchar, optchar);
437 			optopt = optchar;
438 			return (BADARG);
439 		} else				/* white space */
440 			place = nargv[optind];
441 		optchar = parse_long_options(nargv, options, long_options,
442 		    idx, 0);
443 		place = EMSG;
444 		return (optchar);
445 	}
446 	if (*++oli != ':') {			/* doesn't take argument */
447 		if (!*place)
448 			++optind;
449 	} else {				/* takes (optional) argument */
450 		optarg = NULL;
451 		if (*place)			/* no white space */
452 			optarg = place;
453 		else if (oli[1] != ':') {	/* arg not optional */
454 			if (++optind >= nargc) {	/* no arg */
455 				place = EMSG;
456 				if (PRINT_ERROR)
457 					warnx(recargchar, optchar);
458 				optopt = optchar;
459 				return (BADARG);
460 			} else
461 				optarg = nargv[optind];
462 		}
463 		place = EMSG;
464 		++optind;
465 	}
466 	/* dump back option letter */
467 	return (optchar);
468 }
469 
470 #ifdef REPLACE_GETOPT
471 /*
472  * getopt --
473  *	Parse argc/argv argument vector.
474  *
475  * [eventually this will replace the BSD getopt]
476  */
477 int
478 getopt(int nargc, char * const *nargv, const char *options)
479 {
480 
481 	/*
482 	 * We don't pass FLAG_PERMUTE to getopt_internal() since
483 	 * the BSD getopt(3) (unlike GNU) has never done this.
484 	 *
485 	 * Furthermore, since many privileged programs call getopt()
486 	 * before dropping privileges it makes sense to keep things
487 	 * as simple (and bug-free) as possible.
488 	 */
489 	return (getopt_internal(nargc, nargv, options, NULL, NULL, 0));
490 }
491 #endif /* REPLACE_GETOPT */
492 
493 /*
494  * getopt_long --
495  *	Parse argc/argv argument vector.
496  */
497 int
498 getopt_long(int nargc, char * const *nargv, const char *options,
499     const struct option *long_options, int *idx)
500 {
501 
502 	return (getopt_internal(nargc, nargv, options, long_options, idx,
503 	    FLAG_PERMUTE));
504 }
505 
506 /*
507  * getopt_long_only --
508  *	Parse argc/argv argument vector.
509  */
510 int
511 getopt_long_only(int nargc, char * const *nargv, const char *options,
512     const struct option *long_options, int *idx)
513 {
514 
515 	return (getopt_internal(nargc, nargv, options, long_options, idx,
516 	    FLAG_PERMUTE|FLAG_LONGONLY));
517 }
518