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!
5 
6    Copyright (C) 1987, 88, 89, 90, 91, 92, 93, 94
7    	Free Software Foundation, Inc.
8 
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.
11 
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.
16 
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.
21 
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.  */
26 
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
32 
33 #ifdef HAVE_CONFIG_H
34 #include <config.h>
35 #endif
36 
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
44 
45 #include <stdio.h>
46 
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.  */
54 
55 #if defined (_LIBC) || !defined (__GNU_LIBRARY__)
56 
57 
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.  */
65 
66 /* This version of `getopt' appears to the caller like standard Unix `getopt'
67    but it behaves differently for the user, since it allows the user
68    to intersperse the options with the other arguments.
69 
70    As `getopt' works, it permutes the elements of ARGV so that,
71    when it is done, all the options precede everything else.  Thus
72    all application programs are extended to handle flexible argument order.
73 
74    Setting the environment variable POSIXLY_CORRECT disables permutation.
75    Then the behavior is completely standard.
76 
77    GNU application programs can use a third alternative mode in which
78    they can distinguish the relative order of options and other arguments.  */
79 
80 #include "getopt.h"
81 
82 /* For communication from `getopt' to the caller.
83    When `getopt' finds an option that takes an argument,
84    the argument value is returned here.
85    Also, when `ordering' is RETURN_IN_ORDER,
86    each non-option ARGV-element is returned here.  */
87 
88 char *optarg = NULL;
89 
90 /* Index in ARGV of the next element to be scanned.
91    This is used for communication to and from the caller
92    and for communication between successive calls to `getopt'.
93 
94    On entry to `getopt', zero means this is the first call; initialize.
95 
96    When `getopt' returns EOF, this is the index of the first of the
97    non-option elements that the caller should itself scan.
98 
99    Otherwise, `optind' communicates from one call to the next
100    how much of ARGV has been scanned so far.  */
101 
102 /* XXX 1003.2 says this must be 1 before any call.  */
103 int optind = 0;
104 
105 /* The next char to be scanned in the option-element
106    in which the last option character we returned was found.
107    This allows us to pick up the scan where we left off.
108 
109    If this is zero, or a null string, it means resume the scan
110    by advancing to the next ARGV-element.  */
111 
112 static char *nextchar;
113 
114 /* Callers store zero here to inhibit the error message
115    for unrecognized options.  */
116 
117 int opterr = 1;
118 
119 /* Set to an option character which was unrecognized.
120    This must be initialized on some systems to avoid linking in the
121    system's own getopt implementation.  */
122 
123 int optopt = '?';
124 
125 /* Describe how to deal with options that follow non-option ARGV-elements.
126 
127    If the caller did not specify anything,
128    the default is REQUIRE_ORDER if the environment variable
129    POSIXLY_CORRECT is defined, PERMUTE otherwise.
130 
131    REQUIRE_ORDER means don't recognize them as options;
132    stop option processing when the first non-option is seen.
133    This is what Unix does.
134    This mode of operation is selected by either setting the environment
135    variable POSIXLY_CORRECT, or using `+' as the first character
136    of the list of option characters.
137 
138    PERMUTE is the default.  We permute the contents of ARGV as we scan,
139    so that eventually all the non-options are at the end.  This allows options
140    to be given in any order, even with programs that were not written to
141    expect this.
142 
143    RETURN_IN_ORDER is an option available to programs that were written
144    to expect options and other ARGV-elements in any order and that care about
145    the ordering of the two.  We describe each non-option ARGV-element
146    as if it were the argument of an option with character code 1.
147    Using `-' as the first character of the list of option characters
148    selects this mode of operation.
149 
150    The special argument `--' forces an end of option-scanning regardless
151    of the value of `ordering'.  In the case of RETURN_IN_ORDER, only
152    `--' can cause `getopt' to return EOF with `optind' != ARGC.  */
153 
154 static enum
155 {
156   REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
157 } ordering;
158 
159 /* Value of POSIXLY_CORRECT environment variable.  */
160 static char *posixly_correct;
161 
162 #ifdef	__GNU_LIBRARY__
163 /* We want to avoid inclusion of string.h with non-GNU libraries
164    because there are many ways it can cause trouble.
165    On some systems, it contains special magic macros that don't work
166    in GCC.  */
167 #include <string.h>
168 #define	my_index	strchr
169 #else
170 
171 /* Avoid depending on library functions or files
172    whose names are inconsistent.  */
173 
174 char *getenv ();
175 
176 static char *
my_index(str,chr)177 my_index (str, chr)
178      const char *str;
179      int chr;
180 {
181   while (*str)
182     {
183       if (*str == chr)
184 	return (char *) str;
185       str++;
186     }
187   return 0;
188 }
189 
190 /* If using GCC, we can safely declare strlen this way.
191    If not using GCC, it is ok not to declare it.  */
192 #ifdef __GNUC__
193 /* Note that Motorola Delta 68k R3V7 comes with GCC but not stddef.h.
194    That was relevant to code that was here before.  */
195 #if !defined (__STDC__) || !__STDC__
196 /* gcc with -traditional declares the built-in strlen to return int,
197    and has done so at least since version 2.4.5. -- rms.  */
198 extern int strlen (const char *);
199 #endif /* not __STDC__ */
200 #endif /* __GNUC__ */
201 
202 #endif /* not __GNU_LIBRARY__ */
203 
204 /* Handle permutation of arguments.  */
205 
206 /* Describe the part of ARGV that contains non-options that have
207    been skipped.  `first_nonopt' is the index in ARGV of the first of them;
208    `last_nonopt' is the index after the last of them.  */
209 
210 static int first_nonopt;
211 static int last_nonopt;
212 
213 /* Exchange two adjacent subsequences of ARGV.
214    One subsequence is elements [first_nonopt,last_nonopt)
215    which contains all the non-options that have been skipped so far.
216    The other is elements [last_nonopt,optind), which contains all
217    the options processed since those non-options were skipped.
218 
219    `first_nonopt' and `last_nonopt' are relocated so that they describe
220    the new indices of the non-options in ARGV after they are moved.  */
221 
222 static void
exchange(argv)223 exchange (argv)
224      char **argv;
225 {
226   int bottom = first_nonopt;
227   int middle = last_nonopt;
228   int top = optind;
229   char *tem;
230 
231   /* Exchange the shorter segment with the far end of the longer segment.
232      That puts the shorter segment into the right place.
233      It leaves the longer segment in the right place overall,
234      but it consists of two parts that need to be swapped next.  */
235 
236   while (top > middle && middle > bottom)
237     {
238       if (top - middle > middle - bottom)
239 	{
240 	  /* Bottom segment is the short one.  */
241 	  int len = middle - bottom;
242 	  register int i;
243 
244 	  /* Swap it with the top part of the top segment.  */
245 	  for (i = 0; i < len; i++)
246 	    {
247 	      tem = argv[bottom + i];
248 	      argv[bottom + i] = argv[top - (middle - bottom) + i];
249 	      argv[top - (middle - bottom) + i] = tem;
250 	    }
251 	  /* Exclude the moved bottom segment from further swapping.  */
252 	  top -= len;
253 	}
254       else
255 	{
256 	  /* Top segment is the short one.  */
257 	  int len = top - middle;
258 	  register int i;
259 
260 	  /* Swap it with the bottom part of the bottom segment.  */
261 	  for (i = 0; i < len; i++)
262 	    {
263 	      tem = argv[bottom + i];
264 	      argv[bottom + i] = argv[middle + i];
265 	      argv[middle + i] = tem;
266 	    }
267 	  /* Exclude the moved top segment from further swapping.  */
268 	  bottom += len;
269 	}
270     }
271 
272   /* Update records for the slots the non-options now occupy.  */
273 
274   first_nonopt += (optind - last_nonopt);
275   last_nonopt = optind;
276 }
277 
278 /* Initialize the internal data when the first call is made.  */
279 
280 static const char *
_getopt_initialize(optstring)281 _getopt_initialize (optstring)
282      const char *optstring;
283 {
284   /* Start processing options with ARGV-element 1 (since ARGV-element 0
285      is the program name); the sequence of previously skipped
286      non-option ARGV-elements is empty.  */
287 
288   first_nonopt = last_nonopt = optind = 1;
289 
290   nextchar = NULL;
291 
292   posixly_correct = getenv ("POSIXLY_CORRECT");
293 
294   /* Determine how to handle the ordering of options and nonoptions.  */
295 
296   if (optstring[0] == '-')
297     {
298       ordering = RETURN_IN_ORDER;
299       ++optstring;
300     }
301   else if (optstring[0] == '+')
302     {
303       ordering = REQUIRE_ORDER;
304       ++optstring;
305     }
306   else if (posixly_correct != NULL)
307     ordering = REQUIRE_ORDER;
308   else
309     ordering = PERMUTE;
310 
311   return optstring;
312 }
313 
314 /* Scan elements of ARGV (whose length is ARGC) for option characters
315    given in OPTSTRING.
316 
317    If an element of ARGV starts with '-', and is not exactly "-" or "--",
318    then it is an option element.  The characters of this element
319    (aside from the initial '-') are option characters.  If `getopt'
320    is called repeatedly, it returns successively each of the option characters
321    from each of the option elements.
322 
323    If `getopt' finds another option character, it returns that character,
324    updating `optind' and `nextchar' so that the next call to `getopt' can
325    resume the scan with the following option character or ARGV-element.
326 
327    If there are no more option characters, `getopt' returns `EOF'.
328    Then `optind' is the index in ARGV of the first ARGV-element
329    that is not an option.  (The ARGV-elements have been permuted
330    so that those that are not options now come last.)
331 
332    OPTSTRING is a string containing the legitimate option characters.
333    If an option character is seen that is not listed in OPTSTRING,
334    return '?' after printing an error message.  If you set `opterr' to
335    zero, the error message is suppressed but we still return '?'.
336 
337    If a char in OPTSTRING is followed by a colon, that means it wants an arg,
338    so the following text in the same ARGV-element, or the text of the following
339    ARGV-element, is returned in `optarg'.  Two colons mean an option that
340    wants an optional arg; if there is text in the current ARGV-element,
341    it is returned in `optarg', otherwise `optarg' is set to zero.
342 
343    If OPTSTRING starts with `-' or `+', it requests different methods of
344    handling the non-option ARGV-elements.
345    See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
346 
347    Long-named options begin with `--' instead of `-'.
348    Their names may be abbreviated as long as the abbreviation is unique
349    or is an exact match for some defined option.  If they have an
350    argument, it follows the option name in the same ARGV-element, separated
351    from the option name by a `=', or else the in next ARGV-element.
352    When `getopt' finds a long-named option, it returns 0 if that option's
353    `flag' field is nonzero, the value of the option's `val' field
354    if the `flag' field is zero.
355 
356    The elements of ARGV aren't really const, because we permute them.
357    But we pretend they're const in the prototype to be compatible
358    with other systems.
359 
360    LONGOPTS is a vector of `struct option' terminated by an
361    element containing a name which is zero.
362 
363    LONGIND returns the index in LONGOPT of the long-named option found.
364    It is only valid when a long-named option has been found by the most
365    recent call.
366 
367    If LONG_ONLY is nonzero, '-' as well as '--' can introduce
368    long-named options.  */
369 
370 int
_getopt_internal(argc,argv,optstring,longopts,longind,long_only)371 _getopt_internal (argc, argv, optstring, longopts, longind, long_only)
372      int argc;
373      char *const *argv;
374      const char *optstring;
375      const struct option *longopts;
376      int *longind;
377      int long_only;
378 {
379   optarg = NULL;
380 
381   if (optind == 0)
382     optstring = _getopt_initialize (optstring);
383 
384   if (nextchar == NULL || *nextchar == '\0')
385     {
386       /* Advance to the next ARGV-element.  */
387 
388       if (ordering == PERMUTE)
389 	{
390 	  /* If we have just processed some options following some non-options,
391 	     exchange them so that the options come first.  */
392 
393 	  if (first_nonopt != last_nonopt && last_nonopt != optind)
394 	    exchange ((char **) argv);
395 	  else if (last_nonopt != optind)
396 	    first_nonopt = optind;
397 
398 	  /* Skip any additional non-options
399 	     and extend the range of non-options previously skipped.  */
400 
401 	  while (optind < argc
402 		 && (argv[optind][0] != '-' || argv[optind][1] == '\0'))
403 	    optind++;
404 	  last_nonopt = optind;
405 	}
406 
407       /* The special ARGV-element `--' means premature end of options.
408 	 Skip it like a null option,
409 	 then exchange with previous non-options as if it were an option,
410 	 then skip everything else like a non-option.  */
411 
412       if (optind != argc && !strcmp (argv[optind], "--"))
413 	{
414 	  optind++;
415 
416 	  if (first_nonopt != last_nonopt && last_nonopt != optind)
417 	    exchange ((char **) argv);
418 	  else if (first_nonopt == last_nonopt)
419 	    first_nonopt = optind;
420 	  last_nonopt = argc;
421 
422 	  optind = argc;
423 	}
424 
425       /* If we have done all the ARGV-elements, stop the scan
426 	 and back over any non-options that we skipped and permuted.  */
427 
428       if (optind == argc)
429 	{
430 	  /* Set the next-arg-index to point at the non-options
431 	     that we previously skipped, so the caller will digest them.  */
432 	  if (first_nonopt != last_nonopt)
433 	    optind = first_nonopt;
434 	  return EOF;
435 	}
436 
437       /* If we have come to a non-option and did not permute it,
438 	 either stop the scan or describe it to the caller and pass it by.  */
439 
440       if ((argv[optind][0] != '-' || argv[optind][1] == '\0'))
441 	{
442 	  if (ordering == REQUIRE_ORDER)
443 	    return EOF;
444 	  optarg = argv[optind++];
445 	  return 1;
446 	}
447 
448       /* We have found another option-ARGV-element.
449 	 Skip the initial punctuation.  */
450 
451       nextchar = (argv[optind] + 1
452 		  + (longopts != NULL && argv[optind][1] == '-'));
453     }
454 
455   /* Decode the current option-ARGV-element.  */
456 
457   /* Check whether the ARGV-element is a long option.
458 
459      If long_only and the ARGV-element has the form "-f", where f is
460      a valid short option, don't consider it an abbreviated form of
461      a long option that starts with f.  Otherwise there would be no
462      way to give the -f short option.
463 
464      On the other hand, if there's a long option "fubar" and
465      the ARGV-element is "-fu", do consider that an abbreviation of
466      the long option, just like "--fu", and not "-f" with arg "u".
467 
468      This distinction seems to be the most useful approach.  */
469 
470   if (longopts != NULL
471       && (argv[optind][1] == '-'
472 	  || (long_only && (argv[optind][2] || !my_index (optstring, argv[optind][1])))))
473     {
474       char *nameend;
475       const struct option *p;
476       const struct option *pfound = NULL;
477       int exact = 0;
478       int ambig = 0;
479       int indfound;
480       int option_index;
481 
482       for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
483 	/* Do nothing.  */ ;
484 
485       /* Test all long options for either exact match
486 	 or abbreviated matches.  */
487       for (p = longopts, option_index = 0; p->name; p++, option_index++)
488 	if (!strncmp (p->name, nextchar, nameend - nextchar))
489 	  {
490 	    if (nameend - nextchar == strlen (p->name))
491 	      {
492 		/* Exact match found.  */
493 		pfound = p;
494 		indfound = option_index;
495 		exact = 1;
496 		break;
497 	      }
498 	    else if (pfound == NULL)
499 	      {
500 		/* First nonexact match found.  */
501 		pfound = p;
502 		indfound = option_index;
503 	      }
504 	    else
505 	      /* Second or later nonexact match found.  */
506 	      ambig = 1;
507 	  }
508 
509       if (ambig && !exact)
510 	{
511 	  if (opterr)
512 	    fprintf (stderr, "%s: option `%s' is ambiguous\n",
513 		     argv[0], argv[optind]);
514 	  nextchar += strlen (nextchar);
515 	  optind++;
516 	  return '?';
517 	}
518 
519       if (pfound != NULL)
520 	{
521 	  option_index = indfound;
522 	  optind++;
523 	  if (*nameend)
524 	    {
525 	      /* Don't test has_arg with >, because some C compilers don't
526 		 allow it to be used on enums.  */
527 	      if (pfound->has_arg)
528 		optarg = nameend + 1;
529 	      else
530 		{
531 		  if (opterr)
532 		    {
533 		      if (argv[optind - 1][1] == '-')
534 			/* --option */
535 			fprintf (stderr,
536 				 "%s: option `--%s' doesn't allow an argument\n",
537 				 argv[0], pfound->name);
538 		      else
539 			/* +option or -option */
540 			fprintf (stderr,
541 			     "%s: option `%c%s' doesn't allow an argument\n",
542 			     argv[0], argv[optind - 1][0], pfound->name);
543 		    }
544 		  nextchar += strlen (nextchar);
545 		  return '?';
546 		}
547 	    }
548 	  else if (pfound->has_arg == 1)
549 	    {
550 	      if (optind < argc)
551 		optarg = argv[optind++];
552 	      else
553 		{
554 		  if (opterr)
555 		    fprintf (stderr, "%s: option `%s' requires an argument\n",
556 			     argv[0], argv[optind - 1]);
557 		  nextchar += strlen (nextchar);
558 		  return optstring[0] == ':' ? ':' : '?';
559 		}
560 	    }
561 	  nextchar += strlen (nextchar);
562 	  if (longind != NULL)
563 	    *longind = option_index;
564 	  if (pfound->flag)
565 	    {
566 	      *(pfound->flag) = pfound->val;
567 	      return 0;
568 	    }
569 	  return pfound->val;
570 	}
571 
572       /* Can't find it as a long option.  If this is not getopt_long_only,
573 	 or the option starts with '--' or is not a valid short
574 	 option, then it's an error.
575 	 Otherwise interpret it as a short option.  */
576       if (!long_only || argv[optind][1] == '-'
577 	  || my_index (optstring, *nextchar) == NULL)
578 	{
579 	  if (opterr)
580 	    {
581 	      if (argv[optind][1] == '-')
582 		/* --option */
583 		fprintf (stderr, "%s: unrecognized option `--%s'\n",
584 			 argv[0], nextchar);
585 	      else
586 		/* +option or -option */
587 		fprintf (stderr, "%s: unrecognized option `%c%s'\n",
588 			 argv[0], argv[optind][0], nextchar);
589 	    }
590 	  nextchar = (char *) "";
591 	  optind++;
592 	  return '?';
593 	}
594     }
595 
596   /* Look at and handle the next short option-character.  */
597 
598   {
599     char c = *nextchar++;
600     char *temp = my_index (optstring, c);
601 
602     /* Increment `optind' when we start to process its last character.  */
603     if (*nextchar == '\0')
604       ++optind;
605 
606     if (temp == NULL || c == ':')
607       {
608 	if (opterr)
609 	  {
610 	    if (posixly_correct)
611 	      /* 1003.2 specifies the format of this message.  */
612 	      fprintf (stderr, "%s: illegal option -- %c\n", argv[0], c);
613 	    else
614 	      fprintf (stderr, "%s: invalid option -- %c\n", argv[0], c);
615 	  }
616 	optopt = c;
617 	return '?';
618       }
619     if (temp[1] == ':')
620       {
621 	if (temp[2] == ':')
622 	  {
623 	    /* This is an option that accepts an argument optionally.  */
624 	    if (*nextchar != '\0')
625 	      {
626 		optarg = nextchar;
627 		optind++;
628 	      }
629 	    else
630 	      optarg = NULL;
631 	    nextchar = NULL;
632 	  }
633 	else
634 	  {
635 	    /* This is an option that requires an argument.  */
636 	    if (*nextchar != '\0')
637 	      {
638 		optarg = nextchar;
639 		/* If we end this ARGV-element by taking the rest as an arg,
640 		   we must advance to the next element now.  */
641 		optind++;
642 	      }
643 	    else if (optind == argc)
644 	      {
645 		if (opterr)
646 		  {
647 		    /* 1003.2 specifies the format of this message.  */
648 		    fprintf (stderr, "%s: option requires an argument -- %c\n",
649 			     argv[0], c);
650 		  }
651 		optopt = c;
652 		if (optstring[0] == ':')
653 		  c = ':';
654 		else
655 		  c = '?';
656 	      }
657 	    else
658 	      /* We already incremented `optind' once;
659 		 increment it again when taking next ARGV-elt as argument.  */
660 	      optarg = argv[optind++];
661 	    nextchar = NULL;
662 	  }
663       }
664     return c;
665   }
666 }
667 
668 int
getopt(argc,argv,optstring)669 getopt (argc, argv, optstring)
670      int argc;
671      char *const *argv;
672      const char *optstring;
673 {
674   return _getopt_internal (argc, argv, optstring,
675 			   (const struct option *) 0,
676 			   (int *) 0,
677 			   0);
678 }
679 
680 #endif	/* _LIBC or not __GNU_LIBRARY__.  */
681 
682 #ifdef TEST
683 
684 /* Compile with -DTEST to make an executable for use in testing
685    the above definition of `getopt'.  */
686 
687 int
main(argc,argv)688 main (argc, argv)
689      int argc;
690      char **argv;
691 {
692   int c;
693   int digit_optind = 0;
694 
695   while (1)
696     {
697       int this_option_optind = optind ? optind : 1;
698 
699       c = getopt (argc, argv, "abc:d:0123456789");
700       if (c == EOF)
701 	break;
702 
703       switch (c)
704 	{
705 	case '0':
706 	case '1':
707 	case '2':
708 	case '3':
709 	case '4':
710 	case '5':
711 	case '6':
712 	case '7':
713 	case '8':
714 	case '9':
715 	  if (digit_optind != 0 && digit_optind != this_option_optind)
716 	    printf ("digits occur in two different argv-elements.\n");
717 	  digit_optind = this_option_optind;
718 	  printf ("option %c\n", c);
719 	  break;
720 
721 	case 'a':
722 	  printf ("option a\n");
723 	  break;
724 
725 	case 'b':
726 	  printf ("option b\n");
727 	  break;
728 
729 	case 'c':
730 	  printf ("option c with value `%s'\n", optarg);
731 	  break;
732 
733 	case '?':
734 	  break;
735 
736 	default:
737 	  printf ("?? getopt returned character code 0%o ??\n", c);
738 	}
739     }
740 
741   if (optind < argc)
742     {
743       printf ("non-option ARGV-elements: ");
744       while (optind < argc)
745 	printf ("%s ", argv[optind++]);
746       printf ("\n");
747     }
748 
749   exit (0);
750 }
751 
752 #endif /* TEST */
753