407 lines
12 KiB
C
407 lines
12 KiB
C
/****************************************************************************
|
|
|
|
getopt.c - Read command line options
|
|
|
|
AUTHOR: Gregory Pietsch
|
|
CREATED Fri Jan 10 21:13:05 1997
|
|
|
|
DESCRIPTION:
|
|
|
|
The getopt() function parses the command line arguments. Its arguments argc
|
|
and argv are the argument count and array as passed to the main() function
|
|
on program invocation. The argument optstring is a list of available option
|
|
characters. If such a character is followed by a colon (`:'), the option
|
|
takes an argument, which is placed in optarg. If such a character is
|
|
followed by two colons, the option takes an optional argument, which is
|
|
placed in optarg. If the option does not take an argument, optarg is NULL.
|
|
|
|
The external variable optind is the index of the next array element of argv
|
|
to be processed; it communicates from one call to the next which element to
|
|
process.
|
|
|
|
The getopt_long() function works like getopt() except that it also accepts
|
|
long options started by two dashes `--'. If these take values, it is either
|
|
in the form
|
|
|
|
--arg=value
|
|
|
|
or
|
|
|
|
--arg value
|
|
|
|
It takes the additional arguments longopts which is a pointer to the first
|
|
element of an array of type struct option. The last element of the array
|
|
has to be filled with NULL for the name field.
|
|
|
|
The longind pointer points to the index of the current long option relative
|
|
to longopts if it is non-NULL.
|
|
|
|
The getopt() function returns the option character if the option was found
|
|
successfully, `:' if there was a missing parameter for one of the options,
|
|
`?' for an unknown option character, and EOF for the end of the option list.
|
|
|
|
The getopt_long() function's return value is described in the header file.
|
|
|
|
The function getopt_long_only() is identical to getopt_long(), except that a
|
|
plus sign `+' can introduce long options as well as `--'.
|
|
|
|
The following describes how to deal with options that follow non-option
|
|
argv-elements.
|
|
|
|
If the caller did not specify anything, the default is REQUIRE_ORDER if the
|
|
environment variable POSIXLY_CORRECT is defined, PERMUTE otherwise.
|
|
|
|
REQUIRE_ORDER means don't recognize them as options; stop option processing
|
|
when the first non-option is seen. This is what Unix does. This mode of
|
|
operation is selected by either setting the environment variable
|
|
POSIXLY_CORRECT, or using `+' as the first character of the optstring
|
|
parameter.
|
|
|
|
PERMUTE is the default. We permute the contents of ARGV as we scan, so that
|
|
eventually all the non-options are at the end. This allows options to be
|
|
given in any order, even with programs that were not written to expect this.
|
|
|
|
RETURN_IN_ORDER is an option available to programs that were written to
|
|
expect options and other argv-elements in any order and that care about the
|
|
ordering of the two. We describe each non-option argv-element as if it were
|
|
the argument of an option with character code 1. Using `-' as the first
|
|
character of the optstring parameter selects this mode of operation.
|
|
|
|
The special argument `--' forces an end of option-scanning regardless of the
|
|
value of ordering. In the case of RETURN_IN_ORDER, only `--' can cause
|
|
getopt() and friends to return EOF with optind != argc.
|
|
|
|
COPYRIGHT NOTICE AND DISCLAIMER:
|
|
|
|
Copyright (C) 1997 Gregory Pietsch
|
|
|
|
This file and the accompanying getopt.h header file are hereby placed in the
|
|
public domain without restrictions. Just give the author credit, don't
|
|
claim you wrote it or prevent anyone else from using it.
|
|
|
|
Gregory Pietsch's current e-mail address:
|
|
gpietsch@comcast.net
|
|
****************************************************************************/
|
|
|
|
/* include files */
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <getopt.h>
|
|
|
|
/* macros */
|
|
|
|
/* types */
|
|
typedef enum GETOPT_ORDERING_T
|
|
{
|
|
PERMUTE,
|
|
RETURN_IN_ORDER,
|
|
REQUIRE_ORDER
|
|
} GETOPT_ORDERING_T;
|
|
|
|
/* globally-defined variables */
|
|
char *optarg = NULL;
|
|
int optind = 0;
|
|
int opterr = 1;
|
|
int optopt = '?';
|
|
|
|
/* functions */
|
|
|
|
/* reverse_argv_elements: reverses num elements starting at argv */
|
|
static void
|
|
reverse_argv_elements (char ** argv, int num)
|
|
{
|
|
int i;
|
|
char *tmp;
|
|
|
|
for (i = 0; i < (num >> 1); i++)
|
|
{
|
|
tmp = argv[i];
|
|
argv[i] = argv[num - i - 1];
|
|
argv[num - i - 1] = tmp;
|
|
}
|
|
}
|
|
|
|
/* permute: swap two blocks of argv-elements given their lengths */
|
|
static void
|
|
permute (char *const argv[], int len1, int len2)
|
|
{
|
|
reverse_argv_elements ((char **)argv, len1);
|
|
reverse_argv_elements ((char **)argv, len1 + len2);
|
|
reverse_argv_elements ((char **)argv, len2);
|
|
}
|
|
|
|
/* is_option: is this argv-element an option or the end of the option list? */
|
|
static int
|
|
is_option (char *argv_element, int only)
|
|
{
|
|
return ((argv_element == NULL)
|
|
|| (argv_element[0] == '-') || (only && argv_element[0] == '+'));
|
|
}
|
|
|
|
/* getopt_internal: the function that does all the dirty work */
|
|
static int
|
|
getopt_internal (int argc, char *const argv[], const char *shortopts,
|
|
const struct option *longopts, int *longind, int only)
|
|
{
|
|
GETOPT_ORDERING_T ordering = PERMUTE;
|
|
static size_t optwhere = 0;
|
|
size_t permute_from = 0;
|
|
int num_nonopts = 0;
|
|
int optindex = 0;
|
|
size_t match_chars = 0;
|
|
char *possible_arg = NULL;
|
|
int longopt_match = -1;
|
|
int has_arg = -1;
|
|
char *cp = NULL;
|
|
int arg_next = 0;
|
|
|
|
/* first, deal with silly parameters and easy stuff */
|
|
if (argc == 0 || argv == NULL || (shortopts == NULL && longopts == NULL))
|
|
return EOF;
|
|
if (optind >= argc || argv[optind] == NULL)
|
|
return EOF;
|
|
if (strcmp (argv[optind], "--") == 0)
|
|
{
|
|
optind++;
|
|
return EOF;
|
|
}
|
|
/* if this is our first time through */
|
|
if (optind == 0)
|
|
optind = optwhere = 1;
|
|
|
|
/* define ordering */
|
|
if (shortopts != NULL && (*shortopts == '-' || *shortopts == '+'))
|
|
{
|
|
ordering = (*shortopts == '-') ? RETURN_IN_ORDER : REQUIRE_ORDER;
|
|
shortopts++;
|
|
}
|
|
else
|
|
ordering = (getenv ("POSIXLY_CORRECT") != NULL) ? REQUIRE_ORDER : PERMUTE;
|
|
|
|
/*
|
|
* based on ordering, find our next option, if we're at the beginning of
|
|
* one
|
|
*/
|
|
if (optwhere == 1)
|
|
{
|
|
switch (ordering)
|
|
{
|
|
case PERMUTE:
|
|
permute_from = optind;
|
|
num_nonopts = 0;
|
|
while (!is_option (argv[optind], only))
|
|
{
|
|
optind++;
|
|
num_nonopts++;
|
|
}
|
|
if (argv[optind] == NULL)
|
|
{
|
|
/* no more options */
|
|
optind = permute_from;
|
|
return EOF;
|
|
}
|
|
else if (strcmp (argv[optind], "--") == 0)
|
|
{
|
|
/* no more options, but have to get `--' out of the way */
|
|
permute (argv + permute_from, num_nonopts, 1);
|
|
optind = permute_from + 1;
|
|
return EOF;
|
|
}
|
|
break;
|
|
case RETURN_IN_ORDER:
|
|
if (!is_option (argv[optind], only))
|
|
{
|
|
optarg = argv[optind++];
|
|
return (optopt = 1);
|
|
}
|
|
break;
|
|
case REQUIRE_ORDER:
|
|
if (!is_option (argv[optind], only))
|
|
return EOF;
|
|
break;
|
|
}
|
|
}
|
|
/* we've got an option, so parse it */
|
|
|
|
/* first, is it a long option? */
|
|
if (longopts != NULL
|
|
&& (memcmp (argv[optind], "--", 2) == 0
|
|
|| (only && argv[optind][0] == '+')) && optwhere == 1)
|
|
{
|
|
/* handle long options */
|
|
if (memcmp (argv[optind], "--", 2) == 0)
|
|
optwhere = 2;
|
|
longopt_match = -1;
|
|
possible_arg = strchr (argv[optind] + optwhere, '=');
|
|
if (possible_arg == NULL)
|
|
{
|
|
/* no =, so next argv might be arg */
|
|
match_chars = strlen (argv[optind]);
|
|
possible_arg = argv[optind] + match_chars;
|
|
match_chars = match_chars - optwhere;
|
|
}
|
|
else
|
|
match_chars = (possible_arg - argv[optind]) - optwhere;
|
|
for (optindex = 0; longopts[optindex].name != NULL; optindex++)
|
|
{
|
|
if (memcmp (argv[optind] + optwhere,
|
|
longopts[optindex].name, match_chars) == 0)
|
|
{
|
|
/* do we have an exact match? */
|
|
if (match_chars == (int) (strlen (longopts[optindex].name)))
|
|
{
|
|
longopt_match = optindex;
|
|
break;
|
|
}
|
|
/* do any characters match? */
|
|
else
|
|
{
|
|
if (longopt_match < 0)
|
|
longopt_match = optindex;
|
|
else
|
|
{
|
|
/* we have ambiguous options */
|
|
if (opterr)
|
|
fprintf (stderr, "%s: option `%s' is ambiguous "
|
|
"(could be `--%s' or `--%s')\n",
|
|
argv[0],
|
|
argv[optind],
|
|
longopts[longopt_match].name,
|
|
longopts[optindex].name);
|
|
return (optopt = '?');
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (longopt_match >= 0)
|
|
has_arg = longopts[longopt_match].has_arg;
|
|
}
|
|
/* if we didn't find a long option, is it a short option? */
|
|
if (longopt_match < 0 && shortopts != NULL)
|
|
{
|
|
cp = strchr (shortopts, argv[optind][optwhere]);
|
|
if (cp == NULL)
|
|
{
|
|
/* couldn't find option in shortopts */
|
|
if (opterr)
|
|
fprintf (stderr,
|
|
"%s: invalid option -- `-%c'\n",
|
|
argv[0], argv[optind][optwhere]);
|
|
optwhere++;
|
|
if (argv[optind][optwhere] == '\0')
|
|
{
|
|
optind++;
|
|
optwhere = 1;
|
|
}
|
|
return (optopt = '?');
|
|
}
|
|
has_arg = ((cp[1] == ':')
|
|
? ((cp[2] == ':') ? OPTIONAL_ARG : REQUIRED_ARG) : NO_ARG);
|
|
possible_arg = argv[optind] + optwhere + 1;
|
|
optopt = *cp;
|
|
}
|
|
/* get argument and reset optwhere */
|
|
arg_next = 0;
|
|
switch (has_arg)
|
|
{
|
|
case OPTIONAL_ARG:
|
|
if (*possible_arg == '=')
|
|
possible_arg++;
|
|
if (*possible_arg != '\0')
|
|
{
|
|
optarg = possible_arg;
|
|
optwhere = 1;
|
|
}
|
|
else
|
|
optarg = NULL;
|
|
break;
|
|
case REQUIRED_ARG:
|
|
if (*possible_arg == '=')
|
|
possible_arg++;
|
|
if (*possible_arg != '\0')
|
|
{
|
|
optarg = possible_arg;
|
|
optwhere = 1;
|
|
}
|
|
else if (optind + 1 >= argc)
|
|
{
|
|
if (opterr)
|
|
{
|
|
fprintf (stderr, "%s: argument required for option `", argv[0]);
|
|
if (longopt_match >= 0)
|
|
fprintf (stderr, "--%s'\n", longopts[longopt_match].name);
|
|
else
|
|
fprintf (stderr, "-%c'\n", *cp);
|
|
}
|
|
optind++;
|
|
return (optopt = ':');
|
|
}
|
|
else
|
|
{
|
|
optarg = argv[optind + 1];
|
|
arg_next = 1;
|
|
optwhere = 1;
|
|
}
|
|
break;
|
|
case NO_ARG:
|
|
if (longopt_match < 0)
|
|
{
|
|
optwhere++;
|
|
if (argv[optind][optwhere] == '\0')
|
|
optwhere = 1;
|
|
}
|
|
else
|
|
optwhere = 1;
|
|
optarg = NULL;
|
|
break;
|
|
}
|
|
|
|
/* do we have to permute or otherwise modify optind? */
|
|
if (ordering == PERMUTE && optwhere == 1 && num_nonopts != 0)
|
|
{
|
|
permute (argv + permute_from, num_nonopts, 1 + arg_next);
|
|
optind = permute_from + 1 + arg_next;
|
|
}
|
|
else if (optwhere == 1)
|
|
optind = optind + 1 + arg_next;
|
|
|
|
/* finally return */
|
|
if (longopt_match >= 0)
|
|
{
|
|
if (longind != NULL)
|
|
*longind = longopt_match;
|
|
if (longopts[longopt_match].flag != NULL)
|
|
{
|
|
*(longopts[longopt_match].flag) = longopts[longopt_match].val;
|
|
return 0;
|
|
}
|
|
else
|
|
return longopts[longopt_match].val;
|
|
}
|
|
else
|
|
return optopt;
|
|
}
|
|
|
|
int
|
|
getopt (int argc, char *const argv[], const char *optstring)
|
|
{
|
|
return getopt_internal (argc, argv, optstring, NULL, NULL, 0);
|
|
}
|
|
|
|
int
|
|
getopt_long (int argc, char *const argv[], const char *shortopts,
|
|
const struct option *longopts, int *longind)
|
|
{
|
|
return getopt_internal (argc, argv, shortopts, longopts, longind, 0);
|
|
}
|
|
|
|
int
|
|
getopt_long_only (int argc, char *const argv[], const char *shortopts,
|
|
const struct option *longopts, int *longind)
|
|
{
|
|
return getopt_internal (argc, argv, shortopts, longopts, longind, 1);
|
|
}
|
|
|
|
/* end of file GETOPT.C */
|