xref: /freebsd/contrib/tcpdump/missing/getopt_long.c (revision c5f3a7f62217f20f0c7b2c4fc3fb2646336b0802)
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 #include "diag-control.h"
61 
62 #define GNU_COMPATIBLE		/* Be more compatible, configure's use us! */
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 #ifdef GNU_COMPATIBLE
78 #define NO_PREFIX	(-1)
79 #define D_PREFIX	0
80 #define DD_PREFIX	1
81 #define W_PREFIX	2
82 #endif
83 
84 char *optarg;
85 int optind, opterr = 1, optopt;
86 
87 static int getopt_internal(int, char * const *, const char *,
88 			   const struct option *, int *, int);
89 static int parse_long_options(char * const *, const char *,
90 			      const struct option *, int *, int, int);
91 static int gcd(int, int);
92 static void permute_args(int, int, int, char * const *);
93 
94 static const char *place = EMSG; /* option letter processing */
95 
96 static int nonopt_start = -1; /* first non option argument (for permute) */
97 static int nonopt_end = -1;   /* first option after non options (for permute) */
98 
99 /* Error messages */
100 static const char recargchar[] = "option requires an argument -- %c";
101 static const char illoptchar[] = "illegal option -- %c"; /* From P1003.2 */
102 #ifdef GNU_COMPATIBLE
103 static int dash_prefix = NO_PREFIX;
104 static const char gnuoptchar[] = "invalid option -- %c";
105 
106 static const char recargstring[] = "option `%s%s' requires an argument";
107 static const char ambig[] = "option `%s%.*s' is ambiguous";
108 static const char noarg[] = "option `%s%.*s' doesn't allow an argument";
109 static const char illoptstring[] = "unrecognized option `%s%s'";
110 #else
111 static const char recargstring[] = "option requires an argument -- %s";
112 static const char ambig[] = "ambiguous option -- %.*s";
113 static const char noarg[] = "option doesn't take an argument -- %.*s";
114 static const char illoptstring[] = "unknown option -- %s";
115 #endif
116 
117 /*
118  * Compute the greatest common divisor of a and b.
119  */
120 static int
121 gcd(int a, int b)
122 {
123 	int c;
124 
125 	c = a % b;
126 	while (c != 0) {
127 		a = b;
128 		b = c;
129 		c = a % b;
130 	}
131 
132 	return (b);
133 }
134 
135 /*
136  * Exchange the block from nonopt_start to nonopt_end with the block
137  * from nonopt_end to opt_end (keeping the same order of arguments
138  * in each block).
139  */
140 static void
141 permute_args(int panonopt_start, int panonopt_end, int opt_end,
142 	char * const *nargv)
143 {
144 	int cstart, cyclelen, i, j, ncycle, nnonopts, nopts, pos;
145 	char *swap;
146 
147 	/*
148 	 * compute lengths of blocks and number and size of cycles
149 	 */
150 	nnonopts = panonopt_end - panonopt_start;
151 	nopts = opt_end - panonopt_end;
152 	ncycle = gcd(nnonopts, nopts);
153 	cyclelen = (opt_end - panonopt_start) / ncycle;
154 
155 	for (i = 0; i < ncycle; i++) {
156 		cstart = panonopt_end+i;
157 		pos = cstart;
158 		for (j = 0; j < cyclelen; j++) {
159 			if (pos >= panonopt_end)
160 				pos -= nnonopts;
161 			else
162 				pos += nopts;
163 			/*
164 			 * This is annoying - I guess the
165 			 * "char * const argv[]" in the declaration
166 			 * of getopt() - and thus getopt_long() -
167 			 * means that it makes a promise not to
168 			 * shuffle the arguments, but here we are,
169 			 * shuffling the arguments.
170 			 *
171 			 * (No, it's not a promise that it won't
172 			 * modify any of the argument strings.
173 			 * It's a promise that it won't modify
174 			 * the array of pointers to the argument
175 			 * strings.)
176 			 *
177 			 * So squelch the cast warnings.
178 			 */
179 			swap = nargv[pos];
180 DIAG_OFF_CAST_QUAL
181 			/* LINTED const cast */
182 			((char **) nargv)[pos] = nargv[cstart];
183 			/* LINTED const cast */
184 			((char **)nargv)[cstart] = swap;
185 DIAG_ON_CAST_QUAL
186 		}
187 	}
188 }
189 
190 static void
191 warnx(const char *fmt, ...)
192 {
193 	extern char *program_name;
194 	va_list ap;
195 
196 	va_start(ap, fmt);
197 	fprintf(stderr, "%s: ", program_name);
198 	vfprintf(stderr, fmt, ap);
199 	fprintf(stderr, "\n");
200 	va_end(ap);
201 }
202 
203 /*
204  * parse_long_options --
205  *	Parse long options in argc/argv argument vector.
206  * Returns -1 if short_too is set and the option does not match long_options.
207  */
208 static int
209 parse_long_options(char * const *nargv, const char *options,
210 	const struct option *long_options, int *idx, int short_too, int flags)
211 {
212 	const char *current_argv, *has_equal;
213 #ifdef GNU_COMPATIBLE
214 	const char *current_dash;
215 #endif
216 	size_t current_argv_len;
217 	int i, match, exact_match, second_partial_match;
218 
219 	current_argv = place;
220 #ifdef GNU_COMPATIBLE
221 	switch (dash_prefix) {
222 		case D_PREFIX:
223 			current_dash = "-";
224 			break;
225 		case DD_PREFIX:
226 			current_dash = "--";
227 			break;
228 		case W_PREFIX:
229 			current_dash = "-W ";
230 			break;
231 		default:
232 			current_dash = "";
233 			break;
234 	}
235 #endif
236 	match = -1;
237 	exact_match = 0;
238 	second_partial_match = 0;
239 
240 	optind++;
241 
242 	if ((has_equal = strchr(current_argv, '=')) != NULL) {
243 		/* argument found (--option=arg) */
244 		current_argv_len = has_equal - current_argv;
245 		has_equal++;
246 	} else
247 		current_argv_len = strlen(current_argv);
248 
249 	for (i = 0; long_options[i].name; i++) {
250 		/* find matching long option */
251 		if (strncmp(current_argv, long_options[i].name,
252 		    current_argv_len))
253 			continue;
254 
255 		if (strlen(long_options[i].name) == current_argv_len) {
256 			/* exact match */
257 			match = i;
258 			exact_match = 1;
259 			break;
260 		}
261 		/*
262 		 * If this is a known short option, don't allow
263 		 * a partial match of a single character.
264 		 */
265 		if (short_too && current_argv_len == 1)
266 			continue;
267 
268 		if (match == -1)        /* first partial match */
269 			match = i;
270 		else if ((flags & FLAG_LONGONLY) ||
271 			 long_options[i].has_arg !=
272 			     long_options[match].has_arg ||
273 			 long_options[i].flag != long_options[match].flag ||
274 			 long_options[i].val != long_options[match].val)
275 			second_partial_match = 1;
276 	}
277 	if (!exact_match && second_partial_match) {
278 		/* ambiguous abbreviation */
279 		if (PRINT_ERROR)
280 			warnx(ambig,
281 #ifdef GNU_COMPATIBLE
282 			     current_dash,
283 #endif
284 			     (int)current_argv_len,
285 			     current_argv);
286 		optopt = 0;
287 		return (BADCH);
288 	}
289 	if (match != -1) {		/* option found */
290 		if (long_options[match].has_arg == no_argument
291 		    && has_equal) {
292 			if (PRINT_ERROR)
293 				warnx(noarg,
294 #ifdef GNU_COMPATIBLE
295 				     current_dash,
296 #endif
297 				     (int)current_argv_len,
298 				     current_argv);
299 			/*
300 			 * XXX: GNU sets optopt to val regardless of flag
301 			 */
302 			if (long_options[match].flag == NULL)
303 				optopt = long_options[match].val;
304 			else
305 				optopt = 0;
306 #ifdef GNU_COMPATIBLE
307 			return (BADCH);
308 #else
309 			return (BADARG);
310 #endif
311 		}
312 		if (long_options[match].has_arg == required_argument ||
313 		    long_options[match].has_arg == optional_argument) {
314 DIAG_OFF_CAST_QUAL
315 			if (has_equal)
316 				optarg = (char *)has_equal;
317 			else if (long_options[match].has_arg ==
318 			    required_argument) {
319 				/*
320 				 * optional argument doesn't use next nargv
321 				 */
322 				optarg = nargv[optind++];
323 			}
324 DIAG_ON_CAST_QUAL
325 		}
326 		if ((long_options[match].has_arg == required_argument)
327 		    && (optarg == NULL)) {
328 			/*
329 			 * Missing argument; leading ':' indicates no error
330 			 * should be generated.
331 			 */
332 			if (PRINT_ERROR)
333 				warnx(recargstring,
334 #ifdef GNU_COMPATIBLE
335 				    current_dash,
336 #endif
337 				    current_argv);
338 			/*
339 			 * XXX: GNU sets optopt to val regardless of flag
340 			 */
341 			if (long_options[match].flag == NULL)
342 				optopt = long_options[match].val;
343 			else
344 				optopt = 0;
345 			--optind;
346 			return (BADARG);
347 		}
348 	} else {			/* unknown option */
349 		if (short_too) {
350 			--optind;
351 			return (-1);
352 		}
353 		if (PRINT_ERROR)
354 			warnx(illoptstring,
355 #ifdef GNU_COMPATIBLE
356 			      current_dash,
357 #endif
358 			      current_argv);
359 		optopt = 0;
360 		return (BADCH);
361 	}
362 	if (idx)
363 		*idx = match;
364 	if (long_options[match].flag) {
365 		*long_options[match].flag = long_options[match].val;
366 		return (0);
367 	} else
368 		return (long_options[match].val);
369 }
370 
371 /*
372  * getopt_internal --
373  *	Parse argc/argv argument vector.  Called by user level routines.
374  */
375 static int
376 getopt_internal(int nargc, char * const *nargv, const char *options,
377 	const struct option *long_options, int *idx, int flags)
378 {
379 	char *oli;				/* option letter list index */
380 	int optchar, short_too;
381 	int posixly_correct;	/* no static, can be changed on the fly */
382 
383 	if (options == NULL)
384 		return (-1);
385 
386 	/*
387 	 * Disable GNU extensions if POSIXLY_CORRECT is set or options
388 	 * string begins with a '+'.
389 	 */
390 	posixly_correct = (getenv("POSIXLY_CORRECT") != NULL);
391 #ifdef GNU_COMPATIBLE
392 	if (*options == '-')
393 		flags |= FLAG_ALLARGS;
394 	else if (posixly_correct || *options == '+')
395 		flags &= ~FLAG_PERMUTE;
396 #else
397 	if (posixly_correct || *options == '+')
398 		flags &= ~FLAG_PERMUTE;
399 	else if (*options == '-')
400 		flags |= FLAG_ALLARGS;
401 #endif
402 	if (*options == '+' || *options == '-')
403 		options++;
404 
405 	/*
406 	 * XXX Some GNU programs (like cvs) set optind to 0 instead of
407 	 * XXX using optreset.  Work around this braindamage.
408 	 */
409 	if (optind == 0)
410 		optind = 1;
411 
412 	optarg = NULL;
413 start:
414 	if (!*place) {				/* update scanning pointer */
415 		if (optind >= nargc) {          /* end of argument vector */
416 			place = EMSG;
417 			if (nonopt_end != -1) {
418 				/* do permutation, if we have to */
419 				permute_args(nonopt_start, nonopt_end,
420 				    optind, nargv);
421 				optind -= nonopt_end - nonopt_start;
422 			} else if (nonopt_start != -1) {
423 				/*
424 				 * If we skipped non-options, set optind
425 				 * to the first of them.
426 				 */
427 				optind = nonopt_start;
428 			}
429 			nonopt_start = nonopt_end = -1;
430 			return (-1);
431 		}
432 		if (*(place = nargv[optind]) != '-' ||
433 #ifdef GNU_COMPATIBLE
434 		    place[1] == '\0') {
435 #else
436 		    (place[1] == '\0' && strchr(options, '-') == NULL)) {
437 #endif
438 			place = EMSG;		/* found non-option */
439 			if (flags & FLAG_ALLARGS) {
440 				/*
441 				 * GNU extension:
442 				 * return non-option as argument to option 1
443 				 */
444 				optarg = nargv[optind++];
445 				return (INORDER);
446 			}
447 			if (!(flags & FLAG_PERMUTE)) {
448 				/*
449 				 * If no permutation wanted, stop parsing
450 				 * at first non-option.
451 				 */
452 				return (-1);
453 			}
454 			/* do permutation */
455 			if (nonopt_start == -1)
456 				nonopt_start = optind;
457 			else if (nonopt_end != -1) {
458 				permute_args(nonopt_start, nonopt_end,
459 				    optind, nargv);
460 				nonopt_start = optind -
461 				    (nonopt_end - nonopt_start);
462 				nonopt_end = -1;
463 			}
464 			optind++;
465 			/* process next argument */
466 			goto start;
467 		}
468 		if (nonopt_start != -1 && nonopt_end == -1)
469 			nonopt_end = optind;
470 
471 		/*
472 		 * If we have "-" do nothing, if "--" we are done.
473 		 */
474 		if (place[1] != '\0' && *++place == '-' && place[1] == '\0') {
475 			optind++;
476 			place = EMSG;
477 			/*
478 			 * We found an option (--), so if we skipped
479 			 * non-options, we have to permute.
480 			 */
481 			if (nonopt_end != -1) {
482 				permute_args(nonopt_start, nonopt_end,
483 				    optind, nargv);
484 				optind -= nonopt_end - nonopt_start;
485 			}
486 			nonopt_start = nonopt_end = -1;
487 			return (-1);
488 		}
489 	}
490 
491 	/*
492 	 * Check long options if:
493 	 *  1) we were passed some
494 	 *  2) the arg is not just "-"
495 	 *  3) either the arg starts with -- we are getopt_long_only()
496 	 */
497 	if (long_options != NULL && place != nargv[optind] &&
498 	    (*place == '-' || (flags & FLAG_LONGONLY))) {
499 		short_too = 0;
500 #ifdef GNU_COMPATIBLE
501 		dash_prefix = D_PREFIX;
502 #endif
503 		if (*place == '-') {
504 			place++;		/* --foo long option */
505 #ifdef GNU_COMPATIBLE
506 			dash_prefix = DD_PREFIX;
507 #endif
508 		} else if (*place != ':' && strchr(options, *place) != NULL)
509 			short_too = 1;		/* could be short option too */
510 
511 		optchar = parse_long_options(nargv, options, long_options,
512 		    idx, short_too, flags);
513 		if (optchar != -1) {
514 			place = EMSG;
515 			return (optchar);
516 		}
517 	}
518 
519 	if ((optchar = (int)*place++) == (int)':' ||
520 	    (optchar == (int)'-' && *place != '\0') ||
521 	    (oli = strchr(options, optchar)) == NULL) {
522 		/*
523 		 * If the user specified "-" and  '-' isn't listed in
524 		 * options, return -1 (non-option) as per POSIX.
525 		 * Otherwise, it is an unknown option character (or ':').
526 		 */
527 		if (optchar == (int)'-' && *place == '\0')
528 			return (-1);
529 		if (!*place)
530 			++optind;
531 #ifdef GNU_COMPATIBLE
532 		if (PRINT_ERROR)
533 			warnx(posixly_correct ? illoptchar : gnuoptchar,
534 			      optchar);
535 #else
536 		if (PRINT_ERROR)
537 			warnx(illoptchar, optchar);
538 #endif
539 		optopt = optchar;
540 		return (BADCH);
541 	}
542 	if (long_options != NULL && optchar == 'W' && oli[1] == ';') {
543 		/* -W long-option */
544 		if (*place)			/* no space */
545 			/* NOTHING */;
546 		else if (++optind >= nargc) {	/* no arg */
547 			place = EMSG;
548 			if (PRINT_ERROR)
549 				warnx(recargchar, optchar);
550 			optopt = optchar;
551 			return (BADARG);
552 		} else				/* white space */
553 			place = nargv[optind];
554 #ifdef GNU_COMPATIBLE
555 		dash_prefix = W_PREFIX;
556 #endif
557 		optchar = parse_long_options(nargv, options, long_options,
558 		    idx, 0, flags);
559 		place = EMSG;
560 		return (optchar);
561 	}
562 	if (*++oli != ':') {			/* doesn't take argument */
563 		if (!*place)
564 			++optind;
565 	} else {				/* takes (optional) argument */
566 		optarg = NULL;
567 		if (*place) {			/* no white space */
568 DIAG_OFF_CAST_QUAL
569 			optarg = (char *)place;
570 DIAG_ON_CAST_QUAL
571 		} else if (oli[1] != ':') {	/* arg not optional */
572 			if (++optind >= nargc) {	/* no arg */
573 				place = EMSG;
574 				if (PRINT_ERROR)
575 					warnx(recargchar, optchar);
576 				optopt = optchar;
577 				return (BADARG);
578 			} else
579 				optarg = nargv[optind];
580 		}
581 		place = EMSG;
582 		++optind;
583 	}
584 	/* dump back option letter */
585 	return (optchar);
586 }
587 
588 #ifdef REPLACE_GETOPT
589 /*
590  * getopt --
591  *	Parse argc/argv argument vector.
592  *
593  * [eventually this will replace the BSD getopt]
594  */
595 int
596 getopt(int nargc, char * const *nargv, const char *options)
597 {
598 
599 	/*
600 	 * We don't pass FLAG_PERMUTE to getopt_internal() since
601 	 * the BSD getopt(3) (unlike GNU) has never done this.
602 	 *
603 	 * Furthermore, since many privileged programs call getopt()
604 	 * before dropping privileges it makes sense to keep things
605 	 * as simple (and bug-free) as possible.
606 	 */
607 	return (getopt_internal(nargc, nargv, options, NULL, NULL, 0));
608 }
609 #endif /* REPLACE_GETOPT */
610 
611 /*
612  * getopt_long --
613  *	Parse argc/argv argument vector.
614  */
615 int
616 getopt_long(int nargc, char * const *nargv, const char *options,
617 	const struct option *long_options, int *idx)
618 {
619 
620 	return (getopt_internal(nargc, nargv, options, long_options, idx,
621 	    FLAG_PERMUTE));
622 }
623 
624 /*
625  * getopt_long_only --
626  *	Parse argc/argv argument vector.
627  */
628 int
629 getopt_long_only(int nargc, char * const *nargv, const char *options,
630 	const struct option *long_options, int *idx)
631 {
632 
633 	return (getopt_internal(nargc, nargv, options, long_options, idx,
634 	    FLAG_PERMUTE|FLAG_LONGONLY));
635 }
636