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 drepper@gnu.org
6
Copyright (C) 1987, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98
7
Free Software Foundation, Inc.
9
NOTE: The canonical source of this file is maintained with the GNU C Library.
10
Bugs can be reported to bug-glibc@gnu.org.
12
This program is free software; you can redistribute it and/or modify it
13
under the terms of the GNU General Public License as published by the
14
Free Software Foundation; either version 2, or (at your option) any
17
This program 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
20
GNU General Public License for more details.
22
You should have received a copy of the GNU General Public License
23
along with this program; if not, write to the Free Software
24
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
27
/* This tells Alpha OSF/1 not to define a getopt prototype in <stdio.h>.
28
Ditto for AIX 3.2 and <stdlib.h>. */
37
#if !defined __STDC__ || !__STDC__
38
/* This is a separate conditional since some stdc systems
39
reject `defined (const)'. */
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
#define GETOPT_INTERFACE_VERSION 2
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#if !defined _LIBC && defined __GLIBC__ && __GLIBC__ >= 2
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# include <gnu-versions.h>
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# if _GNU_GETOPT_INTERFACE_VERSION == GETOPT_INTERFACE_VERSION
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/* This needs to come after some library #include
67
to get __GNU_LIBRARY__ defined. */
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#ifdef __GNU_LIBRARY__
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/* Don't include stdlib.h for non-GNU C libraries because some of them
70
contain conflicting prototypes for getopt. */
73
#endif /* GNU C library. */
77
# if HAVE_STRING_H - 0
83
/* This is for other GNU distributions with internationalized messages.
84
When compiling libc, the _ macro is predefined. */
85
# ifdef HAVE_LIBINTL_H
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# define _(msgid) gettext (msgid)
89
# define _(msgid) (msgid)
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/* This version of `getopt' appears to the caller like standard Unix `getopt'
94
but it behaves differently for the user, since it allows the user
95
to intersperse the options with the other arguments.
97
As `getopt' works, it permutes the elements of ARGV so that,
98
when it is done, all the options precede everything else. Thus
99
all application programs are extended to handle flexible argument order.
101
Setting the environment variable POSIXLY_CORRECT disables permutation.
102
Then the behavior is completely standard.
104
GNU application programs can use a third alternative mode in which
105
they can distinguish the relative order of options and other arguments. */
109
/* For communication from `getopt' to the caller.
110
When `getopt' finds an option that takes an argument,
111
the argument value is returned here.
112
Also, when `ordering' is RETURN_IN_ORDER,
113
each non-option ARGV-element is returned here. */
117
/* Index in ARGV of the next element to be scanned.
118
This is used for communication to and from the caller
119
and for communication between successive calls to `getopt'.
121
On entry to `getopt', zero means this is the first call; initialize.
123
When `getopt' returns -1, this is the index of the first of the
124
non-option elements that the caller should itself scan.
126
Otherwise, `optind' communicates from one call to the next
127
how much of ARGV has been scanned so far. */
129
/* 1003.2 says this must be 1 before any call. */
132
/* Formerly, initialization of getopt depended on optind==0, which
133
causes problems with re-calling getopt as programs generally don't
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int __getopt_initialized = 0;
138
/* The next char to be scanned in the option-element
139
in which the last option character we returned was found.
140
This allows us to pick up the scan where we left off.
142
If this is zero, or a null string, it means resume the scan
143
by advancing to the next ARGV-element. */
145
static char *nextchar;
147
/* Callers store zero here to inhibit the error message
148
for unrecognized options. */
152
/* Set to an option character which was unrecognized.
153
This must be initialized on some systems to avoid linking in the
154
system's own getopt implementation. */
158
/* Describe how to deal with options that follow non-option ARGV-elements.
160
If the caller did not specify anything,
161
the default is REQUIRE_ORDER if the environment variable
162
POSIXLY_CORRECT is defined, PERMUTE otherwise.
164
REQUIRE_ORDER means don't recognize them as options;
165
stop option processing when the first non-option is seen.
166
This is what Unix does.
167
This mode of operation is selected by either setting the environment
168
variable POSIXLY_CORRECT, or using `+' as the first character
169
of the list of option characters.
171
PERMUTE is the default. We permute the contents of ARGV as we scan,
172
so that eventually all the non-options are at the end. This allows options
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to be given in any order, even with programs that were not written to
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RETURN_IN_ORDER is an option available to programs that were written
177
to expect options and other ARGV-elements in any order and that care about
178
the ordering of the two. We describe each non-option ARGV-element
179
as if it were the argument of an option with character code 1.
180
Using `-' as the first character of the list of option characters
181
selects this mode of operation.
183
The special argument `--' forces an end of option-scanning regardless
184
of the value of `ordering'. In the case of RETURN_IN_ORDER, only
185
`--' can cause `getopt' to return -1 with `optind' != ARGC. */
189
REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
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/* Value of POSIXLY_CORRECT environment variable. */
193
static char *posixly_correct;
195
#ifdef __GNU_LIBRARY__
196
/* We want to avoid inclusion of string.h with non-GNU libraries
197
because there are many ways it can cause trouble.
198
On some systems, it contains special magic macros that don't work
201
# define my_index strchr
208
# include <strings.h>
212
/* Avoid depending on library functions or files
213
whose names are inconsistent. */
216
extern char *getenv ();
233
/* If using GCC, we can safely declare strlen this way.
234
If not using GCC, it is ok not to declare it. */
236
/* Note that Motorola Delta 68k R3V7 comes with GCC but not stddef.h.
237
That was relevant to code that was here before. */
238
# if (!defined __STDC__ || !__STDC__) && !defined strlen
239
/* gcc with -traditional declares the built-in strlen to return int,
240
and has done so at least since version 2.4.5. -- rms. */
241
extern int strlen (const char *);
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# endif /* not __STDC__ */
243
#endif /* __GNUC__ */
245
#endif /* not __GNU_LIBRARY__ */
247
/* Handle permutation of arguments. */
249
/* Describe the part of ARGV that contains non-options that have
250
been skipped. `first_nonopt' is the index in ARGV of the first of them;
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`last_nonopt' is the index after the last of them. */
253
static int first_nonopt;
254
static int last_nonopt;
257
/* Bash 2.0 gives us an environment variable containing flags
258
indicating ARGV elements that should not be considered arguments. */
260
/* Defined in getopt_init.c */
261
extern char *__getopt_nonoption_flags;
263
static int nonoption_flags_max_len;
264
static int nonoption_flags_len;
266
static int original_argc;
267
static char *const *original_argv;
269
/* Make sure the environment variable bash 2.0 puts in the environment
270
is valid for the getopt call we must make sure that the ARGV passed
271
to getopt is that one passed to the process. */
273
__attribute__ ((unused))
274
store_args_and_env (int argc, char *const *argv)
276
/* XXX This is no good solution. We should rather copy the args so
277
that we can compare them later. But we must not use malloc(3). */
278
original_argc = argc;
279
original_argv = argv;
281
# ifdef text_set_element
282
text_set_element (__libc_subinit, store_args_and_env);
283
# endif /* text_set_element */
285
# define SWAP_FLAGS(ch1, ch2) \
286
if (nonoption_flags_len > 0) \
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char __tmp = __getopt_nonoption_flags[ch1]; \
289
__getopt_nonoption_flags[ch1] = __getopt_nonoption_flags[ch2]; \
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__getopt_nonoption_flags[ch2] = __tmp; \
293
# define SWAP_FLAGS(ch1, ch2)
296
/* Exchange two adjacent subsequences of ARGV.
297
One subsequence is elements [first_nonopt,last_nonopt)
298
which contains all the non-options that have been skipped so far.
299
The other is elements [last_nonopt,optind), which contains all
300
the options processed since those non-options were skipped.
302
`first_nonopt' and `last_nonopt' are relocated so that they describe
303
the new indices of the non-options in ARGV after they are moved. */
305
#if defined __STDC__ && __STDC__
306
static void exchange (char **);
313
int bottom = first_nonopt;
314
int middle = last_nonopt;
318
/* Exchange the shorter segment with the far end of the longer segment.
319
That puts the shorter segment into the right place.
320
It leaves the longer segment in the right place overall,
321
but it consists of two parts that need to be swapped next. */
324
/* First make sure the handling of the `__getopt_nonoption_flags'
325
string can work normally. Our top argument must be in the range
327
if (nonoption_flags_len > 0 && top >= nonoption_flags_max_len)
329
/* We must extend the array. The user plays games with us and
330
presents new arguments. */
331
char *new_str = malloc (top + 1);
333
nonoption_flags_len = nonoption_flags_max_len = 0;
336
memset (__mempcpy (new_str, __getopt_nonoption_flags,
337
nonoption_flags_max_len),
338
'\0', top + 1 - nonoption_flags_max_len);
339
nonoption_flags_max_len = top + 1;
340
__getopt_nonoption_flags = new_str;
345
while (top > middle && middle > bottom)
347
if (top - middle > middle - bottom)
349
/* Bottom segment is the short one. */
350
int len = middle - bottom;
353
/* Swap it with the top part of the top segment. */
354
for (i = 0; i < len; i++)
356
tem = argv[bottom + i];
357
argv[bottom + i] = argv[top - (middle - bottom) + i];
358
argv[top - (middle - bottom) + i] = tem;
359
SWAP_FLAGS (bottom + i, top - (middle - bottom) + i);
361
/* Exclude the moved bottom segment from further swapping. */
366
/* Top segment is the short one. */
367
int len = top - middle;
370
/* Swap it with the bottom part of the bottom segment. */
371
for (i = 0; i < len; i++)
373
tem = argv[bottom + i];
374
argv[bottom + i] = argv[middle + i];
375
argv[middle + i] = tem;
376
SWAP_FLAGS (bottom + i, middle + i);
378
/* Exclude the moved top segment from further swapping. */
383
/* Update records for the slots the non-options now occupy. */
385
first_nonopt += (optind - last_nonopt);
386
last_nonopt = optind;
389
/* Initialize the internal data when the first call is made. */
391
#if defined __STDC__ && __STDC__
392
static const char *_getopt_initialize (int, char *const *, const char *);
395
_getopt_initialize (argc, argv, optstring)
398
const char *optstring;
400
/* Start processing options with ARGV-element 1 (since ARGV-element 0
401
is the program name); the sequence of previously skipped
402
non-option ARGV-elements is empty. */
404
first_nonopt = last_nonopt = optind;
408
posixly_correct = getenv ("POSIXLY_CORRECT");
410
/* Determine how to handle the ordering of options and nonoptions. */
412
if (optstring[0] == '-')
414
ordering = RETURN_IN_ORDER;
417
else if (optstring[0] == '+')
419
ordering = REQUIRE_ORDER;
422
else if (posixly_correct != NULL)
423
ordering = REQUIRE_ORDER;
428
if (posixly_correct == NULL
429
&& argc == original_argc && argv == original_argv)
431
if (nonoption_flags_max_len == 0)
433
if (__getopt_nonoption_flags == NULL
434
|| __getopt_nonoption_flags[0] == '\0')
435
nonoption_flags_max_len = -1;
438
const char *orig_str = __getopt_nonoption_flags;
439
int len = nonoption_flags_max_len = strlen (orig_str);
440
if (nonoption_flags_max_len < argc)
441
nonoption_flags_max_len = argc;
442
__getopt_nonoption_flags =
443
(char *) malloc (nonoption_flags_max_len);
444
if (__getopt_nonoption_flags == NULL)
445
nonoption_flags_max_len = -1;
447
memset (__mempcpy (__getopt_nonoption_flags, orig_str, len),
448
'\0', nonoption_flags_max_len - len);
451
nonoption_flags_len = nonoption_flags_max_len;
454
nonoption_flags_len = 0;
460
/* Scan elements of ARGV (whose length is ARGC) for option characters
463
If an element of ARGV starts with '-', and is not exactly "-" or "--",
464
then it is an option element. The characters of this element
465
(aside from the initial '-') are option characters. If `getopt'
466
is called repeatedly, it returns successively each of the option characters
467
from each of the option elements.
469
If `getopt' finds another option character, it returns that character,
470
updating `optind' and `nextchar' so that the next call to `getopt' can
471
resume the scan with the following option character or ARGV-element.
473
If there are no more option characters, `getopt' returns -1.
474
Then `optind' is the index in ARGV of the first ARGV-element
475
that is not an option. (The ARGV-elements have been permuted
476
so that those that are not options now come last.)
478
OPTSTRING is a string containing the legitimate option characters.
479
If an option character is seen that is not listed in OPTSTRING,
480
return '?' after printing an error message. If you set `opterr' to
481
zero, the error message is suppressed but we still return '?'.
483
If a char in OPTSTRING is followed by a colon, that means it wants an arg,
484
so the following text in the same ARGV-element, or the text of the following
485
ARGV-element, is returned in `optarg'. Two colons mean an option that
486
wants an optional arg; if there is text in the current ARGV-element,
487
it is returned in `optarg', otherwise `optarg' is set to zero.
489
If OPTSTRING starts with `-' or `+', it requests different methods of
490
handling the non-option ARGV-elements.
491
See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
493
Long-named options begin with `--' instead of `-'.
494
Their names may be abbreviated as long as the abbreviation is unique
495
or is an exact match for some defined option. If they have an
496
argument, it follows the option name in the same ARGV-element, separated
497
from the option name by a `=', or else the in next ARGV-element.
498
When `getopt' finds a long-named option, it returns 0 if that option's
499
`flag' field is nonzero, the value of the option's `val' field
500
if the `flag' field is zero.
502
The elements of ARGV aren't really const, because we permute them.
503
But we pretend they're const in the prototype to be compatible
506
LONGOPTS is a vector of `struct option' terminated by an
507
element containing a name which is zero.
509
LONGIND returns the index in LONGOPT of the long-named option found.
510
It is only valid when a long-named option has been found by the most
513
If LONG_ONLY is nonzero, '-' as well as '--' can introduce
514
long-named options. */
517
_getopt_internal (argc, argv, optstring, longopts, longind, long_only)
520
const char *optstring;
521
const struct option *longopts;
527
if (optind == 0 || !__getopt_initialized)
530
optind = 1; /* Don't scan ARGV[0], the program name. */
531
optstring = _getopt_initialize (argc, argv, optstring);
532
__getopt_initialized = 1;
535
/* Test whether ARGV[optind] points to a non-option argument.
536
Either it does not have option syntax, or there is an environment flag
537
from the shell indicating it is not an option. The later information
538
is only used when the used in the GNU libc. */
540
# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0' \
541
|| (optind < nonoption_flags_len \
542
&& __getopt_nonoption_flags[optind] == '1'))
544
# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0')
547
if (nextchar == NULL || *nextchar == '\0')
549
/* Advance to the next ARGV-element. */
551
/* Give FIRST_NONOPT & LAST_NONOPT rational values if OPTIND has been
552
moved back by the user (who may also have changed the arguments). */
553
if (last_nonopt > optind)
554
last_nonopt = optind;
555
if (first_nonopt > optind)
556
first_nonopt = optind;
558
if (ordering == PERMUTE)
560
/* If we have just processed some options following some non-options,
561
exchange them so that the options come first. */
563
if (first_nonopt != last_nonopt && last_nonopt != optind)
564
exchange ((char **) argv);
565
else if (last_nonopt != optind)
566
first_nonopt = optind;
568
/* Skip any additional non-options
569
and extend the range of non-options previously skipped. */
571
while (optind < argc && NONOPTION_P)
573
last_nonopt = optind;
576
/* The special ARGV-element `--' means premature end of options.
577
Skip it like a null option,
578
then exchange with previous non-options as if it were an option,
579
then skip everything else like a non-option. */
581
if (optind != argc && !strcmp (argv[optind], "--"))
585
if (first_nonopt != last_nonopt && last_nonopt != optind)
586
exchange ((char **) argv);
587
else if (first_nonopt == last_nonopt)
588
first_nonopt = optind;
594
/* If we have done all the ARGV-elements, stop the scan
595
and back over any non-options that we skipped and permuted. */
599
/* Set the next-arg-index to point at the non-options
600
that we previously skipped, so the caller will digest them. */
601
if (first_nonopt != last_nonopt)
602
optind = first_nonopt;
606
/* If we have come to a non-option and did not permute it,
607
either stop the scan or describe it to the caller and pass it by. */
611
if (ordering == REQUIRE_ORDER)
613
optarg = argv[optind++];
617
/* We have found another option-ARGV-element.
618
Skip the initial punctuation. */
620
nextchar = (argv[optind] + 1
621
+ (longopts != NULL && argv[optind][1] == '-'));
624
/* Decode the current option-ARGV-element. */
626
/* Check whether the ARGV-element is a long option.
628
If long_only and the ARGV-element has the form "-f", where f is
629
a valid short option, don't consider it an abbreviated form of
630
a long option that starts with f. Otherwise there would be no
631
way to give the -f short option.
633
On the other hand, if there's a long option "fubar" and
634
the ARGV-element is "-fu", do consider that an abbreviation of
635
the long option, just like "--fu", and not "-f" with arg "u".
637
This distinction seems to be the most useful approach. */
640
&& (argv[optind][1] == '-'
641
|| (long_only && (argv[optind][2] || !my_index (optstring, argv[optind][1])))))
644
const struct option *p;
645
const struct option *pfound = NULL;
651
for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
654
/* Test all long options for either exact match
655
or abbreviated matches. */
656
for (p = longopts, option_index = 0; p->name; p++, option_index++)
657
if (!strncmp (p->name, nextchar, nameend - nextchar))
659
if ((unsigned int) (nameend - nextchar)
660
== (unsigned int) strlen (p->name))
662
/* Exact match found. */
664
indfound = option_index;
668
else if (pfound == NULL)
670
/* First nonexact match found. */
672
indfound = option_index;
675
/* Second or later nonexact match found. */
682
fprintf (stderr, _("%s: option `%s' is ambiguous\n"),
683
argv[0], argv[optind]);
684
nextchar += strlen (nextchar);
692
option_index = indfound;
696
/* Don't test has_arg with >, because some C compilers don't
697
allow it to be used on enums. */
699
optarg = nameend + 1;
704
if (argv[optind - 1][1] == '-')
707
_("%s: option `--%s' doesn't allow an argument\n"),
708
argv[0], pfound->name);
710
/* +option or -option */
712
_("%s: option `%c%s' doesn't allow an argument\n"),
713
argv[0], argv[optind - 1][0], pfound->name);
715
nextchar += strlen (nextchar);
717
optopt = pfound->val;
722
else if (pfound->has_arg == 1)
725
optarg = argv[optind++];
730
_("%s: option `%s' requires an argument\n"),
731
argv[0], argv[optind - 1]);
732
nextchar += strlen (nextchar);
733
optopt = pfound->val;
734
return optstring[0] == ':' ? ':' : '?';
737
nextchar += strlen (nextchar);
739
*longind = option_index;
742
*(pfound->flag) = pfound->val;
748
/* Can't find it as a long option. If this is not getopt_long_only,
749
or the option starts with '--' or is not a valid short
750
option, then it's an error.
751
Otherwise interpret it as a short option. */
752
if (!long_only || argv[optind][1] == '-'
753
|| my_index (optstring, *nextchar) == NULL)
757
if (argv[optind][1] == '-')
759
fprintf (stderr, _("%s: unrecognized option `--%s'\n"),
762
/* +option or -option */
763
fprintf (stderr, _("%s: unrecognized option `%c%s'\n"),
764
argv[0], argv[optind][0], nextchar);
766
nextchar = (char *) "";
773
/* Look at and handle the next short option-character. */
776
char c = *nextchar++;
777
char *temp = my_index (optstring, c);
779
/* Increment `optind' when we start to process its last character. */
780
if (*nextchar == '\0')
783
if (temp == NULL || c == ':')
788
/* 1003.2 specifies the format of this message. */
789
fprintf (stderr, _("%s: illegal option -- %c\n"),
792
fprintf (stderr, _("%s: invalid option -- %c\n"),
798
/* Convenience. Treat POSIX -W foo same as long option --foo */
799
if (temp[0] == 'W' && temp[1] == ';')
802
const struct option *p;
803
const struct option *pfound = NULL;
809
/* This is an option that requires an argument. */
810
if (*nextchar != '\0')
813
/* If we end this ARGV-element by taking the rest as an arg,
814
we must advance to the next element now. */
817
else if (optind == argc)
821
/* 1003.2 specifies the format of this message. */
822
fprintf (stderr, _("%s: option requires an argument -- %c\n"),
826
if (optstring[0] == ':')
833
/* We already incremented `optind' once;
834
increment it again when taking next ARGV-elt as argument. */
835
optarg = argv[optind++];
837
/* optarg is now the argument, see if it's in the
838
table of longopts. */
840
for (nextchar = nameend = optarg; *nameend && *nameend != '='; nameend++)
843
/* Test all long options for either exact match
844
or abbreviated matches. */
845
for (p = longopts, option_index = 0; p->name; p++, option_index++)
846
if (!strncmp (p->name, nextchar, nameend - nextchar))
848
if ((unsigned int) (nameend - nextchar) == strlen (p->name))
850
/* Exact match found. */
852
indfound = option_index;
856
else if (pfound == NULL)
858
/* First nonexact match found. */
860
indfound = option_index;
863
/* Second or later nonexact match found. */
869
fprintf (stderr, _("%s: option `-W %s' is ambiguous\n"),
870
argv[0], argv[optind]);
871
nextchar += strlen (nextchar);
877
option_index = indfound;
880
/* Don't test has_arg with >, because some C compilers don't
881
allow it to be used on enums. */
883
optarg = nameend + 1;
887
fprintf (stderr, _("\
888
%s: option `-W %s' doesn't allow an argument\n"),
889
argv[0], pfound->name);
891
nextchar += strlen (nextchar);
895
else if (pfound->has_arg == 1)
898
optarg = argv[optind++];
903
_("%s: option `%s' requires an argument\n"),
904
argv[0], argv[optind - 1]);
905
nextchar += strlen (nextchar);
906
return optstring[0] == ':' ? ':' : '?';
909
nextchar += strlen (nextchar);
911
*longind = option_index;
914
*(pfound->flag) = pfound->val;
920
return 'W'; /* Let the application handle it. */
926
/* This is an option that accepts an argument optionally. */
927
if (*nextchar != '\0')
938
/* This is an option that requires an argument. */
939
if (*nextchar != '\0')
942
/* If we end this ARGV-element by taking the rest as an arg,
943
we must advance to the next element now. */
946
else if (optind == argc)
950
/* 1003.2 specifies the format of this message. */
952
_("%s: option requires an argument -- %c\n"),
956
if (optstring[0] == ':')
962
/* We already incremented `optind' once;
963
increment it again when taking next ARGV-elt as argument. */
964
optarg = argv[optind++];
973
getopt (argc, argv, optstring)
976
const char *optstring;
978
return _getopt_internal (argc, argv, optstring,
979
(const struct option *) 0,
984
#endif /* Not ELIDE_CODE. */
988
/* Compile with -DTEST to make an executable for use in testing
989
the above definition of `getopt'. */
997
int digit_optind = 0;
1001
int this_option_optind = optind ? optind : 1;
1003
c = getopt (argc, argv, "abc:d:0123456789");
1019
if (digit_optind != 0 && digit_optind != this_option_optind)
1020
printf ("digits occur in two different argv-elements.\n");
1021
digit_optind = this_option_optind;
1022
printf ("option %c\n", c);
1026
printf ("option a\n");
1030
printf ("option b\n");
1034
printf ("option c with value `%s'\n", optarg);
1041
printf ("?? getopt returned character code 0%o ??\n", c);
1047
printf ("non-option ARGV-elements: ");
1048
while (optind < argc)
1049
printf ("%s ", argv[optind++]);
added
removed
src/getopt.c
