(STRTOF): Fix handling of numbers with lots of leading zeroes.
[glibc.git] / posix / getopt.c
blob85647e2d3657875161a0cb6b893f344945af4853
1 /* Getopt for GNU.
2 NOTE: getopt is now part of the C library, so if you don't know what
3 "Keep this file name-space clean" means, talk to roland@gnu.ai.mit.edu
4 before changing it!
6 Copyright (C) 1987, 88, 89, 90, 91, 92, 93, 94, 95
7 Free Software Foundation, Inc.
9 This file is part of the GNU C Library. Its master source is NOT part of
10 the C library, however. The master source lives in /gd/gnu/lib.
12 The GNU C Library is free software; you can redistribute it and/or
13 modify it under the terms of the GNU Library General Public License as
14 published by the Free Software Foundation; either version 2 of the
15 License, or (at your option) any later version.
17 The GNU C Library is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 Library General Public License for more details.
22 You should have received a copy of the GNU Library General Public
23 License along with the GNU C Library; see the file COPYING.LIB. If
24 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
25 Cambridge, MA 02139, USA. */
27 /* This tells Alpha OSF/1 not to define a getopt prototype in <stdio.h>.
28 Ditto for AIX 3.2 and <stdlib.h>. */
29 #ifndef _NO_PROTO
30 #define _NO_PROTO
31 #endif
33 #ifdef HAVE_CONFIG_H
34 #include <config.h>
35 #endif
37 #if !defined (__STDC__) || !__STDC__
38 /* This is a separate conditional since some stdc systems
39 reject `defined (const)'. */
40 #ifndef const
41 #define const
42 #endif
43 #endif
45 #include <stdio.h>
47 /* Comment out all this code if we are using the GNU C Library, and are not
48 actually compiling the library itself. This code is part of the GNU C
49 Library, but also included in many other GNU distributions. Compiling
50 and linking in this code is a waste when using the GNU C library
51 (especially if it is a shared library). Rather than having every GNU
52 program understand `configure --with-gnu-libc' and omit the object files,
53 it is simpler to just do this in the source for each such file. */
55 #if defined (_LIBC) || !defined (__GNU_LIBRARY__)
58 /* This needs to come after some library #include
59 to get __GNU_LIBRARY__ defined. */
60 #ifdef __GNU_LIBRARY__
61 /* Don't include stdlib.h for non-GNU C libraries because some of them
62 contain conflicting prototypes for getopt. */
63 #include <stdlib.h>
64 #endif /* GNU C library. */
66 /* This is for other GNU distributions with internationalized messages.
67 The GNU C Library itself does not yet support such messages. */
68 #if HAVE_LIBINTL_H
69 # include <libintl.h>
70 #else
71 # define gettext(msgid) (msgid)
72 #endif
74 /* This version of `getopt' appears to the caller like standard Unix `getopt'
75 but it behaves differently for the user, since it allows the user
76 to intersperse the options with the other arguments.
78 As `getopt' works, it permutes the elements of ARGV so that,
79 when it is done, all the options precede everything else. Thus
80 all application programs are extended to handle flexible argument order.
82 Setting the environment variable POSIXLY_CORRECT disables permutation.
83 Then the behavior is completely standard.
85 GNU application programs can use a third alternative mode in which
86 they can distinguish the relative order of options and other arguments. */
88 #include "getopt.h"
90 /* For communication from `getopt' to the caller.
91 When `getopt' finds an option that takes an argument,
92 the argument value is returned here.
93 Also, when `ordering' is RETURN_IN_ORDER,
94 each non-option ARGV-element is returned here. */
96 char *optarg = NULL;
98 /* Index in ARGV of the next element to be scanned.
99 This is used for communication to and from the caller
100 and for communication between successive calls to `getopt'.
102 On entry to `getopt', zero means this is the first call; initialize.
104 When `getopt' returns EOF, this is the index of the first of the
105 non-option elements that the caller should itself scan.
107 Otherwise, `optind' communicates from one call to the next
108 how much of ARGV has been scanned so far. */
110 /* XXX 1003.2 says this must be 1 before any call. */
111 int optind = 0;
113 /* The next char to be scanned in the option-element
114 in which the last option character we returned was found.
115 This allows us to pick up the scan where we left off.
117 If this is zero, or a null string, it means resume the scan
118 by advancing to the next ARGV-element. */
120 static char *nextchar;
122 /* Callers store zero here to inhibit the error message
123 for unrecognized options. */
125 int opterr = 1;
127 /* Set to an option character which was unrecognized.
128 This must be initialized on some systems to avoid linking in the
129 system's own getopt implementation. */
131 int optopt = '?';
133 /* Describe how to deal with options that follow non-option ARGV-elements.
135 If the caller did not specify anything,
136 the default is REQUIRE_ORDER if the environment variable
137 POSIXLY_CORRECT is defined, PERMUTE otherwise.
139 REQUIRE_ORDER means don't recognize them as options;
140 stop option processing when the first non-option is seen.
141 This is what Unix does.
142 This mode of operation is selected by either setting the environment
143 variable POSIXLY_CORRECT, or using `+' as the first character
144 of the list of option characters.
146 PERMUTE is the default. We permute the contents of ARGV as we scan,
147 so that eventually all the non-options are at the end. This allows options
148 to be given in any order, even with programs that were not written to
149 expect this.
151 RETURN_IN_ORDER is an option available to programs that were written
152 to expect options and other ARGV-elements in any order and that care about
153 the ordering of the two. We describe each non-option ARGV-element
154 as if it were the argument of an option with character code 1.
155 Using `-' as the first character of the list of option characters
156 selects this mode of operation.
158 The special argument `--' forces an end of option-scanning regardless
159 of the value of `ordering'. In the case of RETURN_IN_ORDER, only
160 `--' can cause `getopt' to return EOF with `optind' != ARGC. */
162 static enum
164 REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
165 } ordering;
167 /* Value of POSIXLY_CORRECT environment variable. */
168 static char *posixly_correct;
170 #ifdef __GNU_LIBRARY__
171 /* We want to avoid inclusion of string.h with non-GNU libraries
172 because there are many ways it can cause trouble.
173 On some systems, it contains special magic macros that don't work
174 in GCC. */
175 #include <string.h>
176 #define my_index strchr
177 #else
179 /* Avoid depending on library functions or files
180 whose names are inconsistent. */
182 char *getenv ();
184 static char *
185 my_index (str, chr)
186 const char *str;
187 int chr;
189 while (*str)
191 if (*str == chr)
192 return (char *) str;
193 str++;
195 return 0;
198 /* If using GCC, we can safely declare strlen this way.
199 If not using GCC, it is ok not to declare it. */
200 #ifdef __GNUC__
201 /* Note that Motorola Delta 68k R3V7 comes with GCC but not stddef.h.
202 That was relevant to code that was here before. */
203 #if !defined (__STDC__) || !__STDC__
204 /* gcc with -traditional declares the built-in strlen to return int,
205 and has done so at least since version 2.4.5. -- rms. */
206 extern int strlen (const char *);
207 #endif /* not __STDC__ */
208 #endif /* __GNUC__ */
210 #endif /* not __GNU_LIBRARY__ */
212 /* Handle permutation of arguments. */
214 /* Describe the part of ARGV that contains non-options that have
215 been skipped. `first_nonopt' is the index in ARGV of the first of them;
216 `last_nonopt' is the index after the last of them. */
218 static int first_nonopt;
219 static int last_nonopt;
221 /* Exchange two adjacent subsequences of ARGV.
222 One subsequence is elements [first_nonopt,last_nonopt)
223 which contains all the non-options that have been skipped so far.
224 The other is elements [last_nonopt,optind), which contains all
225 the options processed since those non-options were skipped.
227 `first_nonopt' and `last_nonopt' are relocated so that they describe
228 the new indices of the non-options in ARGV after they are moved. */
230 static void
231 exchange (argv)
232 char **argv;
234 int bottom = first_nonopt;
235 int middle = last_nonopt;
236 int top = optind;
237 char *tem;
239 /* Exchange the shorter segment with the far end of the longer segment.
240 That puts the shorter segment into the right place.
241 It leaves the longer segment in the right place overall,
242 but it consists of two parts that need to be swapped next. */
244 while (top > middle && middle > bottom)
246 if (top - middle > middle - bottom)
248 /* Bottom segment is the short one. */
249 int len = middle - bottom;
250 register int i;
252 /* Swap it with the top part of the top segment. */
253 for (i = 0; i < len; i++)
255 tem = argv[bottom + i];
256 argv[bottom + i] = argv[top - (middle - bottom) + i];
257 argv[top - (middle - bottom) + i] = tem;
259 /* Exclude the moved bottom segment from further swapping. */
260 top -= len;
262 else
264 /* Top segment is the short one. */
265 int len = top - middle;
266 register int i;
268 /* Swap it with the bottom part of the bottom segment. */
269 for (i = 0; i < len; i++)
271 tem = argv[bottom + i];
272 argv[bottom + i] = argv[middle + i];
273 argv[middle + i] = tem;
275 /* Exclude the moved top segment from further swapping. */
276 bottom += len;
280 /* Update records for the slots the non-options now occupy. */
282 first_nonopt += (optind - last_nonopt);
283 last_nonopt = optind;
286 /* Initialize the internal data when the first call is made. */
288 static const char *
289 _getopt_initialize (optstring)
290 const char *optstring;
292 /* Start processing options with ARGV-element 1 (since ARGV-element 0
293 is the program name); the sequence of previously skipped
294 non-option ARGV-elements is empty. */
296 first_nonopt = last_nonopt = optind = 1;
298 nextchar = NULL;
300 posixly_correct = getenv ("POSIXLY_CORRECT");
302 /* Determine how to handle the ordering of options and nonoptions. */
304 if (optstring[0] == '-')
306 ordering = RETURN_IN_ORDER;
307 ++optstring;
309 else if (optstring[0] == '+')
311 ordering = REQUIRE_ORDER;
312 ++optstring;
314 else if (posixly_correct != NULL)
315 ordering = REQUIRE_ORDER;
316 else
317 ordering = PERMUTE;
319 return optstring;
322 /* Scan elements of ARGV (whose length is ARGC) for option characters
323 given in OPTSTRING.
325 If an element of ARGV starts with '-', and is not exactly "-" or "--",
326 then it is an option element. The characters of this element
327 (aside from the initial '-') are option characters. If `getopt'
328 is called repeatedly, it returns successively each of the option characters
329 from each of the option elements.
331 If `getopt' finds another option character, it returns that character,
332 updating `optind' and `nextchar' so that the next call to `getopt' can
333 resume the scan with the following option character or ARGV-element.
335 If there are no more option characters, `getopt' returns `EOF'.
336 Then `optind' is the index in ARGV of the first ARGV-element
337 that is not an option. (The ARGV-elements have been permuted
338 so that those that are not options now come last.)
340 OPTSTRING is a string containing the legitimate option characters.
341 If an option character is seen that is not listed in OPTSTRING,
342 return '?' after printing an error message. If you set `opterr' to
343 zero, the error message is suppressed but we still return '?'.
345 If a char in OPTSTRING is followed by a colon, that means it wants an arg,
346 so the following text in the same ARGV-element, or the text of the following
347 ARGV-element, is returned in `optarg'. Two colons mean an option that
348 wants an optional arg; if there is text in the current ARGV-element,
349 it is returned in `optarg', otherwise `optarg' is set to zero.
351 If OPTSTRING starts with `-' or `+', it requests different methods of
352 handling the non-option ARGV-elements.
353 See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
355 Long-named options begin with `--' instead of `-'.
356 Their names may be abbreviated as long as the abbreviation is unique
357 or is an exact match for some defined option. If they have an
358 argument, it follows the option name in the same ARGV-element, separated
359 from the option name by a `=', or else the in next ARGV-element.
360 When `getopt' finds a long-named option, it returns 0 if that option's
361 `flag' field is nonzero, the value of the option's `val' field
362 if the `flag' field is zero.
364 The elements of ARGV aren't really const, because we permute them.
365 But we pretend they're const in the prototype to be compatible
366 with other systems.
368 LONGOPTS is a vector of `struct option' terminated by an
369 element containing a name which is zero.
371 LONGIND returns the index in LONGOPT of the long-named option found.
372 It is only valid when a long-named option has been found by the most
373 recent call.
375 If LONG_ONLY is nonzero, '-' as well as '--' can introduce
376 long-named options. */
379 _getopt_internal (argc, argv, optstring, longopts, longind, long_only)
380 int argc;
381 char *const *argv;
382 const char *optstring;
383 const struct option *longopts;
384 int *longind;
385 int long_only;
387 optarg = NULL;
389 if (optind == 0)
391 optstring = _getopt_initialize (optstring);
392 optind = 1; /* Don't scan ARGV[0], the program name. */
395 if (nextchar == NULL || *nextchar == '\0')
397 /* Advance to the next ARGV-element. */
399 if (ordering == PERMUTE)
401 /* If we have just processed some options following some non-options,
402 exchange them so that the options come first. */
404 if (first_nonopt != last_nonopt && last_nonopt != optind)
405 exchange ((char **) argv);
406 else if (last_nonopt != optind)
407 first_nonopt = optind;
409 /* Skip any additional non-options
410 and extend the range of non-options previously skipped. */
412 while (optind < argc
413 && (argv[optind][0] != '-' || argv[optind][1] == '\0'))
414 optind++;
415 last_nonopt = optind;
418 /* The special ARGV-element `--' means premature end of options.
419 Skip it like a null option,
420 then exchange with previous non-options as if it were an option,
421 then skip everything else like a non-option. */
423 if (optind != argc && !strcmp (argv[optind], "--"))
425 optind++;
427 if (first_nonopt != last_nonopt && last_nonopt != optind)
428 exchange ((char **) argv);
429 else if (first_nonopt == last_nonopt)
430 first_nonopt = optind;
431 last_nonopt = argc;
433 optind = argc;
436 /* If we have done all the ARGV-elements, stop the scan
437 and back over any non-options that we skipped and permuted. */
439 if (optind == argc)
441 /* Set the next-arg-index to point at the non-options
442 that we previously skipped, so the caller will digest them. */
443 if (first_nonopt != last_nonopt)
444 optind = first_nonopt;
445 return EOF;
448 /* If we have come to a non-option and did not permute it,
449 either stop the scan or describe it to the caller and pass it by. */
451 if ((argv[optind][0] != '-' || argv[optind][1] == '\0'))
453 if (ordering == REQUIRE_ORDER)
454 return EOF;
455 optarg = argv[optind++];
456 return 1;
459 /* We have found another option-ARGV-element.
460 Skip the initial punctuation. */
462 nextchar = (argv[optind] + 1
463 + (longopts != NULL && argv[optind][1] == '-'));
466 /* Decode the current option-ARGV-element. */
468 /* Check whether the ARGV-element is a long option.
470 If long_only and the ARGV-element has the form "-f", where f is
471 a valid short option, don't consider it an abbreviated form of
472 a long option that starts with f. Otherwise there would be no
473 way to give the -f short option.
475 On the other hand, if there's a long option "fubar" and
476 the ARGV-element is "-fu", do consider that an abbreviation of
477 the long option, just like "--fu", and not "-f" with arg "u".
479 This distinction seems to be the most useful approach. */
481 if (longopts != NULL
482 && (argv[optind][1] == '-'
483 || (long_only && (argv[optind][2] || !my_index (optstring, argv[optind][1])))))
485 char *nameend;
486 const struct option *p;
487 const struct option *pfound = NULL;
488 int exact = 0;
489 int ambig = 0;
490 int indfound;
491 int option_index;
493 for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
494 /* Do nothing. */ ;
496 /* Test all long options for either exact match
497 or abbreviated matches. */
498 for (p = longopts, option_index = 0; p->name; p++, option_index++)
499 if (!strncmp (p->name, nextchar, nameend - nextchar))
501 if (nameend - nextchar == strlen (p->name))
503 /* Exact match found. */
504 pfound = p;
505 indfound = option_index;
506 exact = 1;
507 break;
509 else if (pfound == NULL)
511 /* First nonexact match found. */
512 pfound = p;
513 indfound = option_index;
515 else
516 /* Second or later nonexact match found. */
517 ambig = 1;
520 if (ambig && !exact)
522 if (opterr)
523 fprintf (stderr, gettext ("%s: option `%s' is ambiguous\n"),
524 argv[0], argv[optind]);
525 nextchar += strlen (nextchar);
526 optind++;
527 return '?';
530 if (pfound != NULL)
532 option_index = indfound;
533 optind++;
534 if (*nameend)
536 /* Don't test has_arg with >, because some C compilers don't
537 allow it to be used on enums. */
538 if (pfound->has_arg)
539 optarg = nameend + 1;
540 else
542 if (opterr)
543 if (argv[optind - 1][1] == '-')
544 /* --option */
545 fprintf (stderr,
546 gettext ("%s: option `--%s' doesn't allow an argument\n"),
547 argv[0], pfound->name);
548 else
549 /* +option or -option */
550 fprintf (stderr,
551 gettext ("%s: option `%c%s' doesn't allow an argument\n"),
552 argv[0], argv[optind - 1][0], pfound->name);
554 nextchar += strlen (nextchar);
555 return '?';
558 else if (pfound->has_arg == 1)
560 if (optind < argc)
561 optarg = argv[optind++];
562 else
564 if (opterr)
565 fprintf (stderr,
566 gettext ("%s: option `%s' requires an argument\n"),
567 argv[0], argv[optind - 1]);
568 nextchar += strlen (nextchar);
569 return optstring[0] == ':' ? ':' : '?';
572 nextchar += strlen (nextchar);
573 if (longind != NULL)
574 *longind = option_index;
575 if (pfound->flag)
577 *(pfound->flag) = pfound->val;
578 return 0;
580 return pfound->val;
583 /* Can't find it as a long option. If this is not getopt_long_only,
584 or the option starts with '--' or is not a valid short
585 option, then it's an error.
586 Otherwise interpret it as a short option. */
587 if (!long_only || argv[optind][1] == '-'
588 || my_index (optstring, *nextchar) == NULL)
590 if (opterr)
592 if (argv[optind][1] == '-')
593 /* --option */
594 fprintf (stderr, gettext ("%s: unrecognized option `--%s'\n"),
595 argv[0], nextchar);
596 else
597 /* +option or -option */
598 fprintf (stderr, gettext ("%s: unrecognized option `%c%s'\n"),
599 argv[0], argv[optind][0], nextchar);
601 nextchar = (char *) "";
602 optind++;
603 return '?';
607 /* Look at and handle the next short option-character. */
610 char c = *nextchar++;
611 char *temp = my_index (optstring, c);
613 /* Increment `optind' when we start to process its last character. */
614 if (*nextchar == '\0')
615 ++optind;
617 if (temp == NULL || c == ':')
619 if (opterr)
621 if (posixly_correct)
622 /* 1003.2 specifies the format of this message. */
623 fprintf (stderr, gettext ("%s: illegal option -- %c\n"),
624 argv[0], c);
625 else
626 fprintf (stderr, gettext ("%s: invalid option -- %c\n"),
627 argv[0], c);
629 optopt = c;
630 return '?';
632 if (temp[1] == ':')
634 if (temp[2] == ':')
636 /* This is an option that accepts an argument optionally. */
637 if (*nextchar != '\0')
639 optarg = nextchar;
640 optind++;
642 else
643 optarg = NULL;
644 nextchar = NULL;
646 else
648 /* This is an option that requires an argument. */
649 if (*nextchar != '\0')
651 optarg = nextchar;
652 /* If we end this ARGV-element by taking the rest as an arg,
653 we must advance to the next element now. */
654 optind++;
656 else if (optind == argc)
658 if (opterr)
660 /* 1003.2 specifies the format of this message. */
661 fprintf (stderr,
662 gettext ("%s: option requires an argument -- %c\n"),
663 argv[0], c);
665 optopt = c;
666 if (optstring[0] == ':')
667 c = ':';
668 else
669 c = '?';
671 else
672 /* We already incremented `optind' once;
673 increment it again when taking next ARGV-elt as argument. */
674 optarg = argv[optind++];
675 nextchar = NULL;
678 return c;
683 getopt (argc, argv, optstring)
684 int argc;
685 char *const *argv;
686 const char *optstring;
688 return _getopt_internal (argc, argv, optstring,
689 (const struct option *) 0,
690 (int *) 0,
694 #endif /* _LIBC or not __GNU_LIBRARY__. */
696 #ifdef TEST
698 /* Compile with -DTEST to make an executable for use in testing
699 the above definition of `getopt'. */
702 main (argc, argv)
703 int argc;
704 char **argv;
706 int c;
707 int digit_optind = 0;
709 while (1)
711 int this_option_optind = optind ? optind : 1;
713 c = getopt (argc, argv, "abc:d:0123456789");
714 if (c == EOF)
715 break;
717 switch (c)
719 case '0':
720 case '1':
721 case '2':
722 case '3':
723 case '4':
724 case '5':
725 case '6':
726 case '7':
727 case '8':
728 case '9':
729 if (digit_optind != 0 && digit_optind != this_option_optind)
730 printf ("digits occur in two different argv-elements.\n");
731 digit_optind = this_option_optind;
732 printf ("option %c\n", c);
733 break;
735 case 'a':
736 printf ("option a\n");
737 break;
739 case 'b':
740 printf ("option b\n");
741 break;
743 case 'c':
744 printf ("option c with value `%s'\n", optarg);
745 break;
747 case '?':
748 break;
750 default:
751 printf ("?? getopt returned character code 0%o ??\n", c);
755 if (optind < argc)
757 printf ("non-option ARGV-elements: ");
758 while (optind < argc)
759 printf ("%s ", argv[optind++]);
760 printf ("\n");
763 exit (0);
766 #endif /* TEST */