1 /*****************************************************************************
3 *****************************************************************************
4 * Copyright (C) 1987-1997 Free Software Foundation, Inc.
5 * Copyright (C) 2005-2010 the VideoLAN team
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published by
9 * the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this program; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
20 *****************************************************************************/
25 #include <vlc_common.h>
30 /* This version of `getopt' appears to the caller like standard Unix `getopt'
31 but it behaves differently for the user, since it allows the user
32 to intersperse the options with the other arguments.
34 As `getopt' works, it permutes the elements of ARGV so that,
35 when it is done, all the options precede everything else. Thus
36 all application programs are extended to handle flexible argument order.
38 Setting the environment variable POSIXLY_CORRECT disables permutation.
39 Then the behavior is completely standard.
41 GNU application programs can use a third alternative mode in which
42 they can distinguish the relative order of options and other arguments. */
44 #include "vlc_getopt.h"
46 /* For communication from `getopt' to the caller.
47 When `getopt' finds an option that takes an argument,
48 the argument value is returned here.
49 Also, when `ordering' is RETURN_IN_ORDER,
50 each non-option ARGV-element is returned here. */
52 char *vlc_optarg = NULL;
54 /* Index in ARGV of the next element to be scanned.
55 This is used for communication to and from the caller
56 and for communication between successive calls to `getopt'.
58 On entry to `getopt', zero means this is the first call; initialize.
60 When `getopt' returns -1, this is the index of the first of the
61 non-option elements that the caller should itself scan.
63 Otherwise, `optind' communicates from one call to the next
64 how much of ARGV has been scanned so far. */
66 /* 1003.2 says this must be 1 before any call. */
69 /* Formerly, initialization of getopt depended on optind==0, which
70 causes problems with re-calling getopt as programs generally don't
73 static int vlc_getopt_initialized = 0;
75 /* The next char to be scanned in the option-element
76 in which the last option character we returned was found.
77 This allows us to pick up the scan where we left off.
79 If this is zero, or a null string, it means resume the scan
80 by advancing to the next ARGV-element. */
82 static char *nextchar;
84 /* Set to an option character which was unrecognized.
85 This must be initialized on some systems to avoid linking in the
86 system's own getopt implementation. */
90 /* Describe how to deal with options that follow non-option ARGV-elements.
92 If the caller did not specify anything,
93 the default is REQUIRE_ORDER if the environment variable
94 POSIXLY_CORRECT is defined, PERMUTE otherwise.
96 REQUIRE_ORDER means don't recognize them as options;
97 stop option processing when the first non-option is seen.
98 This is what Unix does.
99 This mode of operation is selected by either setting the environment
100 variable POSIXLY_CORRECT, or using `+' as the first character
101 of the list of option characters.
103 PERMUTE is the default. We permute the contents of ARGV as we scan,
104 so that eventually all the non-options are at the end. This allows options
105 to be given in any order, even with programs that were not written to
108 RETURN_IN_ORDER is an option available to programs that were written
109 to expect options and other ARGV-elements in any order and that care about
110 the ordering of the two. We describe each non-option ARGV-element
111 as if it were the argument of an option with character code 1.
112 Using `-' as the first character of the list of option characters
113 selects this mode of operation.
115 The special argument `--' forces an end of option-scanning regardless
116 of the value of `ordering'. In the case of RETURN_IN_ORDER, only
117 `--' can cause `getopt' to return -1 with `optind' != ARGC. */
121 REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
125 /* Value of POSIXLY_CORRECT environment variable. */
126 static char *posixly_correct;
128 /* Handle permutation of arguments. */
130 /* Describe the part of ARGV that contains non-options that have
131 been skipped. `first_nonopt' is the index in ARGV of the first of them;
132 `last_nonopt' is the index after the last of them. */
134 static int first_nonopt;
135 static int last_nonopt;
137 /* Exchange two adjacent subsequences of ARGV.
138 One subsequence is elements [first_nonopt,last_nonopt)
139 which contains all the non-options that have been skipped so far.
140 The other is elements [last_nonopt,optind), which contains all
141 the options processed since those non-options were skipped.
143 `first_nonopt' and `last_nonopt' are relocated so that they describe
144 the new indices of the non-options in ARGV after they are moved. */
146 static void exchange(char **);
152 int bottom = first_nonopt;
153 int middle = last_nonopt;
154 int top = vlc_optind;
157 /* Exchange the shorter segment with the far end of the longer segment.
158 That puts the shorter segment into the right place.
159 It leaves the longer segment in the right place overall,
160 but it consists of two parts that need to be swapped next. */
162 while (top > middle && middle > bottom)
164 if (top - middle > middle - bottom)
166 /* Bottom segment is the short one. */
167 int len = middle - bottom;
170 /* Swap it with the top part of the top segment. */
171 for (i = 0; i < len; i++)
173 tem = argv[bottom + i];
174 argv[bottom + i] = argv[top - (middle - bottom) + i];
175 argv[top - (middle - bottom) + i] = tem;
177 /* Exclude the moved bottom segment from further swapping. */
182 /* Top segment is the short one. */
183 int len = top - middle;
186 /* Swap it with the bottom part of the bottom segment. */
187 for (i = 0; i < len; i++)
189 tem = argv[bottom + i];
190 argv[bottom + i] = argv[middle + i];
191 argv[middle + i] = tem;
193 /* Exclude the moved top segment from further swapping. */
198 /* Update records for the slots the non-options now occupy. */
200 first_nonopt += (vlc_optind - last_nonopt);
201 last_nonopt = vlc_optind;
204 /* Initialize the internal data when the first call is made. */
206 static const char *vlc_getopt_initialize(int, char *const *, const char *);
209 vlc_getopt_initialize(argc, argv, optstring)
212 const char *optstring;
216 /* Start processing options with ARGV-element 1 (since ARGV-element 0
217 is the program name); the sequence of previously skipped
218 non-option ARGV-elements is empty. */
220 first_nonopt = last_nonopt = vlc_optind = 1;
224 posixly_correct = getenv("POSIXLY_CORRECT");
226 /* Determine how to handle the ordering of options and nonoptions. */
228 if (optstring[0] == '-')
230 ordering = RETURN_IN_ORDER;
233 else if (optstring[0] == '+')
235 ordering = REQUIRE_ORDER;
238 else if (posixly_correct != NULL)
239 ordering = REQUIRE_ORDER;
246 /* Scan elements of ARGV (whose length is ARGC) for option characters
249 If an element of ARGV starts with '-', and is not exactly "-" or "--",
250 then it is an option element. The characters of this element
251 (aside from the initial '-') are option characters. If `getopt'
252 is called repeatedly, it returns successively each of the option characters
253 from each of the option elements.
255 If `getopt' finds another option character, it returns that character,
256 updating `optind' and `nextchar' so that the next call to `getopt' can
257 resume the scan with the following option character or ARGV-element.
259 If there are no more option characters, `getopt' returns -1.
260 Then `optind' is the index in ARGV of the first ARGV-element
261 that is not an option. (The ARGV-elements have been permuted
262 so that those that are not options now come last.)
264 OPTSTRING is a string containing the legitimate option characters.
265 If an option character is seen that is not listed in OPTSTRING,
268 If a char in OPTSTRING is followed by a colon, that means it wants an arg,
269 so the following text in the same ARGV-element, or the text of the following
270 ARGV-element, is returned in `optarg'.
272 If OPTSTRING starts with `-' or `+', it requests different methods of
273 handling the non-option ARGV-elements.
274 See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
276 Long-named options begin with `--' instead of `-'.
277 Their names may be abbreviated as long as the abbreviation is unique
278 or is an exact match for some defined option. If they have an
279 argument, it follows the option name in the same ARGV-element, separated
280 from the option name by a `=', or else the in next ARGV-element.
281 When `getopt' finds a long-named option, it returns 0 if that option's
282 `flag' field is nonzero, the value of the option's `val' field
283 if the `flag' field is zero.
285 The elements of ARGV aren't really const, because we permute them.
286 But we pretend they're const in the prototype to be compatible
289 LONGOPTS is a vector of `struct option' terminated by an
290 element containing a name which is zero.
292 LONGIND returns the index in LONGOPT of the long-named option found.
293 It is only valid when a long-named option has been found by the most
297 vlc_getopt_long(argc, argv, optstring, longopts, longind)
300 const char *optstring;
301 const struct vlc_option *restrict longopts;
306 if (!vlc_getopt_initialized || vlc_optind == 0)
308 optstring = vlc_getopt_initialize(argc, argv, optstring);
309 vlc_optind = 1; /* Don't scan ARGV[0], the program name. */
310 vlc_getopt_initialized = 1;
313 #define NONOPTION_P (argv[vlc_optind][0] != '-' || argv[vlc_optind][1] == '\0')
315 if (nextchar == NULL || *nextchar == '\0')
317 /* Advance to the next ARGV-element. */
319 /* Give FIRST_NONOPT & LAST_NONOPT rational values if OPTIND has been
320 moved back by the user (who may also have changed the arguments). */
321 if (last_nonopt > vlc_optind)
322 last_nonopt = vlc_optind;
323 if (first_nonopt > vlc_optind)
324 first_nonopt = vlc_optind;
326 if (ordering == PERMUTE)
328 /* If we have just processed some options following some non-options,
329 exchange them so that the options come first. */
331 if (first_nonopt != last_nonopt && last_nonopt != vlc_optind)
332 exchange((char **) argv);
333 else if (last_nonopt != vlc_optind)
334 first_nonopt = vlc_optind;
336 /* Skip any additional non-options
337 and extend the range of non-options previously skipped. */
339 while (vlc_optind < argc && NONOPTION_P)
341 last_nonopt = vlc_optind;
344 /* The special ARGV-element `--' means premature end of options.
345 Skip it like a null option,
346 then exchange with previous non-options as if it were an option,
347 then skip everything else like a non-option. */
349 if (vlc_optind != argc && !strcmp(argv[vlc_optind], "--"))
353 if (first_nonopt != last_nonopt && last_nonopt != vlc_optind)
354 exchange((char **) argv);
355 else if (first_nonopt == last_nonopt)
356 first_nonopt = vlc_optind;
362 /* If we have done all the ARGV-elements, stop the scan
363 and back over any non-options that we skipped and permuted. */
365 if (vlc_optind == argc)
367 /* Set the next-arg-index to point at the non-options
368 that we previously skipped, so the caller will digest them. */
369 if (first_nonopt != last_nonopt)
370 vlc_optind = first_nonopt;
374 /* If we have come to a non-option and did not permute it,
375 either stop the scan or describe it to the caller and pass it by. */
379 if (ordering == REQUIRE_ORDER)
381 vlc_optarg = argv[vlc_optind++];
385 /* We have found another option-ARGV-element.
386 Skip the initial punctuation. */
388 nextchar = (argv[vlc_optind] + 1
389 + (argv[vlc_optind][1] == '-'));
392 /* Decode the current option-ARGV-element. */
394 /* Check whether the ARGV-element is a long option. */
396 if (argv[vlc_optind][1] == '-')
399 const struct vlc_option *p;
400 const struct vlc_option *pfound = NULL;
406 for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
409 /* Test all long options for either exact match
410 or abbreviated matches. */
411 for (p = longopts, option_index = 0; p->name; p++, option_index++)
412 if (!strncmp(p->name, nextchar, nameend - nextchar))
414 if ((unsigned int) (nameend - nextchar)
415 == (unsigned int) strlen(p->name))
417 /* Exact match found. */
419 indfound = option_index;
423 else if (pfound == NULL)
425 /* First nonexact match found. */
427 indfound = option_index;
430 /* Second or later nonexact match found. */
436 nextchar += strlen(nextchar);
444 option_index = indfound;
449 vlc_optarg = nameend + 1;
452 nextchar += strlen(nextchar);
454 vlc_optopt = pfound->val;
458 else if (pfound->has_arg)
460 if (vlc_optind < argc)
461 vlc_optarg = argv[vlc_optind++];
464 nextchar += strlen(nextchar);
465 vlc_optopt = pfound->val;
466 return optstring[0] == ':' ? ':' : '?';
469 nextchar += strlen(nextchar);
471 *longind = option_index;
474 *(pfound->flag) = pfound->val;
480 nextchar = (char *) "";
486 /* Look at and handle the next short option-character. */
489 char c = *nextchar++;
490 char *temp = strchr(optstring, c);
492 /* Increment `optind' when we start to process its last character. */
493 if (*nextchar == '\0')
496 if (temp == NULL || c == ':')
501 /* Convenience. Treat POSIX -W foo same as long option --foo */
502 if (temp[0] == 'W' && temp[1] == ';')
505 const struct vlc_option *p;
506 const struct vlc_option *pfound = NULL;
512 /* This is an option that requires an argument. */
513 if (*nextchar != '\0')
515 vlc_optarg = nextchar;
516 /* If we end this ARGV-element by taking the rest as an arg,
517 we must advance to the next element now. */
520 else if (vlc_optind == argc)
523 if (optstring[0] == ':')
530 /* We already incremented `optind' once;
531 increment it again when taking next ARGV-elt as argument. */
532 vlc_optarg = argv[vlc_optind++];
534 /* optarg is now the argument, see if it's in the
535 table of longopts. */
537 for (nextchar = nameend = vlc_optarg; *nameend && *nameend != '='; nameend++)
540 /* Test all long options for either exact match
541 or abbreviated matches. */
542 for (p = longopts, option_index = 0; p->name; p++, option_index++)
543 if (!strncmp(p->name, nextchar, nameend - nextchar))
545 if ((unsigned int) (nameend - nextchar) == strlen(p->name))
547 /* Exact match found. */
549 indfound = option_index;
553 else if (pfound == NULL)
555 /* First nonexact match found. */
557 indfound = option_index;
560 /* Second or later nonexact match found. */
565 nextchar += strlen(nextchar);
571 option_index = indfound;
575 vlc_optarg = nameend + 1;
578 nextchar += strlen(nextchar);
582 else if (pfound->has_arg)
584 if (vlc_optind < argc)
585 vlc_optarg = argv[vlc_optind++];
588 nextchar += strlen(nextchar);
589 return optstring[0] == ':' ? ':' : '?';
592 nextchar += strlen(nextchar);
594 *longind = option_index;
597 *(pfound->flag) = pfound->val;
603 return 'W'; /* Let the application handle it. */
607 /* This is an option that requires an argument. */
608 if (*nextchar != '\0')
610 vlc_optarg = nextchar;
611 /* If we end this ARGV-element by taking the rest as an arg,
612 we must advance to the next element now. */
615 else if (vlc_optind == argc)
618 if (optstring[0] == ':')
624 /* We already incremented `optind' once;
625 increment it again when taking next ARGV-elt as argument. */
626 vlc_optarg = argv[vlc_optind++];