Copyright (C) 1987-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library and is also part of gnulib.
Patches to this file should be submitted to both projects.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <libc-symbols.h>
#ifndef _LIBC
# include <config.h>
#endif
#include "getopt.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifdef __HAIKU__
#define _(msgid) msgid
#define _GL_UNUSED
#elif defined(_LIBC)
for standards compliance. getopt is not a cancellation point, so
it must not call functions that are, and it is specified by an
older standard than stdio locking, so it must not refer to
functions in the "user namespace" related to stdio locking.
Finally, it must use glibc's internal message translation so that
the messages are looked up in the proper text domain. */
# include <libintl.h>
# define fprintf __fxprintf_nocancel
# define flockfile(fp) _IO_flockfile (fp)
# define funlockfile(fp) _IO_funlockfile (fp)
#else
# include "gettext.h"
# define _(msgid) gettext (msgid)
available. */
# if (!defined _POSIX_THREAD_SAFE_FUNCTIONS \
|| (defined _WIN32 && ! defined __CYGWIN__))
# define flockfile(fp)
# define funlockfile(fp)
# endif
# define __libc_use_alloca(size) 0
# undef alloca
# define alloca(size) (abort (), (void *)0)
#endif
options interspersed with non-option arguments. It can stop
scanning for options at the first non-option argument encountered,
as POSIX specifies. It can continue scanning for options after the
first non-option argument, but permute 'argv' as it goes so that,
after 'getopt' is done, all the options precede all the non-option
arguments and 'optind' points to the first non-option argument.
Or, it can report non-option arguments as if they were arguments to
the option character '\x01'.
The default behavior of 'getopt_long' is to permute the argument list.
When this implementation is used standalone, the default behavior of
'getopt' is to stop at the first non-option argument, but when it is
used as part of GNU libc it also permutes the argument list. In both
cases, setting the environment variable POSIXLY_CORRECT to any value
disables permutation.
If the first character of the OPTSTRING argument to 'getopt' or
'getopt_long' is '+', both functions will stop at the first
non-option argument. If it is '-', both functions will report
non-option arguments as arguments to the option character '\x01'. */
#include "getopt_int.h"
When 'getopt' finds an option that takes an argument,
the argument value is returned here.
Also, when 'ordering' is RETURN_IN_ORDER,
each non-option ARGV-element is returned here. */
char *optarg;
This is used for communication to and from the caller
and for communication between successive calls to 'getopt'.
On entry to 'getopt', zero means this is the first call; initialize.
When 'getopt' returns -1, this is the index of the first of the
non-option elements that the caller should itself scan.
Otherwise, 'optind' communicates from one call to the next
how much of ARGV has been scanned so far. */
int optind = 1;
for unrecognized options. */
int opterr = 1;
This must be initialized on some systems to avoid linking in the
system's own getopt implementation. */
int optopt = '?';
static struct _getopt_data getopt_data;
One subsequence is elements [first_nonopt,last_nonopt)
which contains all the non-options that have been skipped so far.
The other is elements [last_nonopt,optind), which contains all
the options processed since those non-options were skipped.
'first_nonopt' and 'last_nonopt' are relocated so that they describe
the new indices of the non-options in ARGV after they are moved. */
static void
exchange (char **argv, struct _getopt_data *d)
{
int bottom = d->__first_nonopt;
int middle = d->__last_nonopt;
int top = d->optind;
char *tem;
That puts the shorter segment into the right place.
It leaves the longer segment in the right place overall,
but it consists of two parts that need to be swapped next. */
while (top > middle && middle > bottom)
{
if (top - middle > middle - bottom)
{
int len = middle - bottom;
int i;
for (i = 0; i < len; i++)
{
tem = argv[bottom + i];
argv[bottom + i] = argv[top - (middle - bottom) + i];
argv[top - (middle - bottom) + i] = tem;
}
top -= len;
}
else
{
int len = top - middle;
int i;
for (i = 0; i < len; i++)
{
tem = argv[bottom + i];
argv[bottom + i] = argv[middle + i];
argv[middle + i] = tem;
}
bottom += len;
}
}
d->__first_nonopt += (d->optind - d->__last_nonopt);
d->__last_nonopt = d->optind;
}
d->optind should *not* have been advanced over this argument.
If the value returned is -1, it was not actually a long option, the
state is unchanged, and the argument should be processed as a set
of short options (this can only happen when long_only is true).
Otherwise, the option (and its argument, if any) have been consumed
and the return value is the value to return from _getopt_internal_r. */
static int
process_long_option (int argc, char **argv, const char *optstring,
const struct option *longopts, int *longind,
int long_only, struct _getopt_data *d,
int print_errors, const char *prefix)
{
char *nameend;
size_t namelen;
const struct option *p;
const struct option *pfound = NULL;
int n_options;
int option_index;
for (nameend = d->__nextchar; *nameend && *nameend != '='; nameend++)
;
namelen = nameend - d->__nextchar;
effect. */
for (p = longopts, n_options = 0; p->name; p++, n_options++)
if (!strncmp (p->name, d->__nextchar, namelen)
&& namelen == strlen (p->name))
{
pfound = p;
option_index = n_options;
break;
}
if (pfound == NULL)
{
unsigned char *ambig_set = NULL;
int ambig_malloced = 0;
int ambig_fallback = 0;
int indfound = -1;
for (p = longopts, option_index = 0; p->name; p++, option_index++)
if (!strncmp (p->name, d->__nextchar, namelen))
{
if (pfound == NULL)
{
pfound = p;
indfound = option_index;
}
else if (long_only
|| pfound->has_arg != p->has_arg
|| pfound->flag != p->flag
|| pfound->val != p->val)
{
if (!ambig_fallback)
{
if (!print_errors)
we're not going to print it anyway. */
ambig_fallback = 1;
else if (!ambig_set)
{
if (__libc_use_alloca (n_options))
ambig_set = alloca (n_options);
else if ((ambig_set = malloc (n_options)) == NULL)
ambig_fallback = 1;
else
ambig_malloced = 1;
if (ambig_set)
{
memset (ambig_set, 0, n_options);
ambig_set[indfound] = 1;
}
}
if (ambig_set)
ambig_set[option_index] = 1;
}
}
}
if (ambig_set || ambig_fallback)
{
if (print_errors)
{
if (ambig_fallback)
fprintf (stderr, _("%s: option '%s%s' is ambiguous\n"),
argv[0], prefix, d->__nextchar);
else
{
flockfile (stderr);
fprintf (stderr,
_("%s: option '%s%s' is ambiguous; possibilities:"),
argv[0], prefix, d->__nextchar);
for (option_index = 0; option_index < n_options; option_index++)
if (ambig_set[option_index])
fprintf (stderr, " '%s%s'",
prefix, longopts[option_index].name);
printing a single character, so that it goes through
__fxprintf_nocancel when compiled as part of glibc. */
fprintf (stderr, "\n");
funlockfile (stderr);
}
}
if (ambig_malloced)
free (ambig_set);
d->__nextchar += strlen (d->__nextchar);
d->optind++;
d->optopt = 0;
return '?';
}
option_index = indfound;
}
if (pfound == NULL)
{
or the option starts with '--' or is not a valid short option,
then it's an error. */
if (!long_only || argv[d->optind][1] == '-'
|| strchr (optstring, *d->__nextchar) == NULL)
{
if (print_errors)
fprintf (stderr, _("%s: unrecognized option '%s%s'\n"),
argv[0], prefix, d->__nextchar);
d->__nextchar = NULL;
d->optind++;
d->optopt = 0;
return '?';
}
return -1;
}
d->optind++;
d->__nextchar = NULL;
if (*nameend)
{
allow it to be used on enums. */
if (pfound->has_arg)
d->optarg = nameend + 1;
else
{
if (print_errors)
fprintf (stderr,
_("%s: option '%s%s' doesn't allow an argument\n"),
argv[0], prefix, pfound->name);
d->optopt = pfound->val;
return '?';
}
}
else if (pfound->has_arg == 1)
{
if (d->optind < argc)
d->optarg = argv[d->optind++];
else
{
if (print_errors)
fprintf (stderr,
_("%s: option '%s%s' requires an argument\n"),
argv[0], prefix, pfound->name);
d->optopt = pfound->val;
return optstring[0] == ':' ? ':' : '?';
}
}
if (longind != NULL)
*longind = option_index;
if (pfound->flag)
{
*(pfound->flag) = pfound->val;
return 0;
}
return pfound->val;
}
static const char *
_getopt_initialize (_GL_UNUSED int argc,
_GL_UNUSED char **argv, const char *optstring,
struct _getopt_data *d, int posixly_correct)
{
is the program name); the sequence of previously skipped
non-option ARGV-elements is empty. */
if (d->optind == 0)
d->optind = 1;
d->__first_nonopt = d->__last_nonopt = d->optind;
d->__nextchar = NULL;
if (optstring[0] == '-')
{
d->__ordering = RETURN_IN_ORDER;
++optstring;
}
else if (optstring[0] == '+')
{
d->__ordering = REQUIRE_ORDER;
++optstring;
}
else if (posixly_correct || !!getenv ("POSIXLY_CORRECT"))
d->__ordering = REQUIRE_ORDER;
else
d->__ordering = PERMUTE;
d->__initialized = 1;
return optstring;
}
given in OPTSTRING.
If an element of ARGV starts with '-', and is not exactly "-" or "--",
then it is an option element. The characters of this element
(aside from the initial '-') are option characters. If 'getopt'
is called repeatedly, it returns successively each of the option characters
from each of the option elements.
If 'getopt' finds another option character, it returns that character,
updating 'optind' and 'nextchar' so that the next call to 'getopt' can
resume the scan with the following option character or ARGV-element.
If there are no more option characters, 'getopt' returns -1.
Then 'optind' is the index in ARGV of the first ARGV-element
that is not an option. (The ARGV-elements have been permuted
so that those that are not options now come last.)
OPTSTRING is a string containing the legitimate option characters.
If an option character is seen that is not listed in OPTSTRING,
return '?' after printing an error message. If you set 'opterr' to
zero, the error message is suppressed but we still return '?'.
If a char in OPTSTRING is followed by a colon, that means it wants an arg,
so the following text in the same ARGV-element, or the text of the following
ARGV-element, is returned in 'optarg'. Two colons mean an option that
wants an optional arg; if there is text in the current ARGV-element,
it is returned in 'optarg', otherwise 'optarg' is set to zero.
If OPTSTRING starts with '-' or '+', it requests different methods of
handling the non-option ARGV-elements.
See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
Long-named options begin with '--' instead of '-'.
Their names may be abbreviated as long as the abbreviation is unique
or is an exact match for some defined option. If they have an
argument, it follows the option name in the same ARGV-element, separated
from the option name by a '=', or else the in next ARGV-element.
When 'getopt' finds a long-named option, it returns 0 if that option's
'flag' field is nonzero, the value of the option's 'val' field
if the 'flag' field is zero.
The elements of ARGV aren't really const, because we permute them.
But we pretend they're const in the prototype to be compatible
with other systems.
LONGOPTS is a vector of 'struct option' terminated by an
element containing a name which is zero.
LONGIND returns the index in LONGOPT of the long-named option found.
It is only valid when a long-named option has been found by the most
recent call.
If LONG_ONLY is nonzero, '-' as well as '--' can introduce
long-named options. */
int
_getopt_internal_r (int argc, char **argv, const char *optstring,
const struct option *longopts, int *longind,
int long_only, struct _getopt_data *d, int posixly_correct)
{
int print_errors = d->opterr;
if (argc < 1)
return -1;
d->optarg = NULL;
if (d->optind == 0 || !d->__initialized)
optstring = _getopt_initialize (argc, argv, optstring, d, posixly_correct);
else if (optstring[0] == '-' || optstring[0] == '+')
optstring++;
if (optstring[0] == ':')
print_errors = 0;
#define NONOPTION_P (argv[d->optind][0] != '-' || argv[d->optind][1] == '\0')
if (d->__nextchar == NULL || *d->__nextchar == '\0')
{
moved back by the user (who may also have changed the arguments). */
if (d->__last_nonopt > d->optind)
d->__last_nonopt = d->optind;
if (d->__first_nonopt > d->optind)
d->__first_nonopt = d->optind;
if (d->__ordering == PERMUTE)
{
exchange them so that the options come first. */
if (d->__first_nonopt != d->__last_nonopt
&& d->__last_nonopt != d->optind)
exchange (argv, d);
else if (d->__last_nonopt != d->optind)
d->__first_nonopt = d->optind;
and extend the range of non-options previously skipped. */
while (d->optind < argc && NONOPTION_P)
d->optind++;
d->__last_nonopt = d->optind;
}
Skip it like a null option,
then exchange with previous non-options as if it were an option,
then skip everything else like a non-option. */
if (d->optind != argc && !strcmp (argv[d->optind], "--"))
{
d->optind++;
if (d->__first_nonopt != d->__last_nonopt
&& d->__last_nonopt != d->optind)
exchange (argv, d);
else if (d->__first_nonopt == d->__last_nonopt)
d->__first_nonopt = d->optind;
d->__last_nonopt = argc;
d->optind = argc;
}
and back over any non-options that we skipped and permuted. */
if (d->optind == argc)
{
that we previously skipped, so the caller will digest them. */
if (d->__first_nonopt != d->__last_nonopt)
d->optind = d->__first_nonopt;
return -1;
}
either stop the scan or describe it to the caller and pass it by. */
if (NONOPTION_P)
{
if (d->__ordering == REQUIRE_ORDER)
return -1;
d->optarg = argv[d->optind++];
return 1;
}
Check whether it might be a long option. */
if (longopts)
{
if (argv[d->optind][1] == '-')
{
"--" was handled above. */
d->__nextchar = argv[d->optind] + 2;
return process_long_option (argc, argv, optstring, longopts,
longind, long_only, d,
print_errors, "--");
}
where f is a valid short option, don't consider it an
abbreviated form of a long option that starts with f.
Otherwise there would be no way to give the -f short
option.
On the other hand, if there's a long option "fubar" and
the ARGV-element is "-fu", do consider that an
abbreviation of the long option, just like "--fu", and
not "-f" with arg "u".
This distinction seems to be the most useful approach. */
if (long_only && (argv[d->optind][2]
|| !strchr (optstring, argv[d->optind][1])))
{
int code;
d->__nextchar = argv[d->optind] + 1;
code = process_long_option (argc, argv, optstring, longopts,
longind, long_only, d,
print_errors, "-");
if (code != -1)
return code;
}
}
d->__nextchar = argv[d->optind] + 1;
}
{
char c = *d->__nextchar++;
const char *temp = strchr (optstring, c);
if (*d->__nextchar == '\0')
++d->optind;
if (temp == NULL || c == ':' || c == ';')
{
if (print_errors)
fprintf (stderr, _("%s: invalid option -- '%c'\n"), argv[0], c);
d->optopt = c;
return '?';
}
if (temp[0] == 'W' && temp[1] == ';' && longopts != NULL)
{
if (*d->__nextchar != '\0')
d->optarg = d->__nextchar;
else if (d->optind == argc)
{
if (print_errors)
fprintf (stderr,
_("%s: option requires an argument -- '%c'\n"),
argv[0], c);
d->optopt = c;
if (optstring[0] == ':')
c = ':';
else
c = '?';
return c;
}
else
d->optarg = argv[d->optind];
d->__nextchar = d->optarg;
d->optarg = NULL;
return process_long_option (argc, argv, optstring, longopts, longind,
0 , d, print_errors, "-W ");
}
if (temp[1] == ':')
{
if (temp[2] == ':')
{
if (*d->__nextchar != '\0')
{
d->optarg = d->__nextchar;
d->optind++;
}
else
d->optarg = NULL;
d->__nextchar = NULL;
}
else
{
if (*d->__nextchar != '\0')
{
d->optarg = d->__nextchar;
we must advance to the next element now. */
d->optind++;
}
else if (d->optind == argc)
{
if (print_errors)
fprintf (stderr,
_("%s: option requires an argument -- '%c'\n"),
argv[0], c);
d->optopt = c;
if (optstring[0] == ':')
c = ':';
else
c = '?';
}
else
increment it again when taking next ARGV-elt as argument. */
d->optarg = argv[d->optind++];
d->__nextchar = NULL;
}
}
return c;
}
}
int
_getopt_internal (int argc, char **argv, const char *optstring,
const struct option *longopts, int *longind, int long_only,
int posixly_correct)
{
int result;
getopt_data.optind = optind;
getopt_data.opterr = opterr;
result = _getopt_internal_r (argc, argv, optstring, longopts,
longind, long_only, &getopt_data,
posixly_correct);
optind = getopt_data.optind;
optarg = getopt_data.optarg;
optopt = getopt_data.optopt;
return result;
}
Standalone applications just get a POSIX-compliant getopt.
POSIX and LSB both require these functions to take 'char *const *argv'
even though this is incorrect (because of the permutation). */
#define GETOPT_ENTRY(NAME, POSIXLY_CORRECT) \
int \
NAME (int argc, char *const *argv, const char *optstring) \
{ \
return _getopt_internal (argc, (char **)argv, optstring, \
NULL, NULL, 0, POSIXLY_CORRECT); \
}
#ifdef _LIBC
GETOPT_ENTRY(getopt, 0)
#ifndef __HAIKU__
GETOPT_ENTRY(__posix_getopt, 1)
#endif
#else
GETOPT_ENTRY(getopt, 1)
#endif
#ifdef TEST
the above definition of 'getopt'. */
int
main (int argc, char **argv)
{
int c;
int digit_optind = 0;
while (1)
{
int this_option_optind = optind ? optind : 1;
c = getopt (argc, argv, "abc:d:0123456789");
if (c == -1)
break;
switch (c)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if (digit_optind != 0 && digit_optind != this_option_optind)
printf ("digits occur in two different argv-elements.\n");
digit_optind = this_option_optind;
printf ("option %c\n", c);
break;
case 'a':
printf ("option a\n");
break;
case 'b':
printf ("option b\n");
break;
case 'c':
printf ("option c with value '%s'\n", optarg);
break;
case '?':
break;
default:
printf ("?? getopt returned character code 0%o ??\n", c);
}
}
if (optind < argc)
{
printf ("non-option ARGV-elements: ");
while (optind < argc)
printf ("%s ", argv[optind++]);
printf ("\n");
}
exit (0);
}
#endif