coreutils/lib/rpmatch.c
2005-09-22 06:05:39 +00:00

80 lines
2.3 KiB
C

/* Determine whether string value is affirmation or negative response
according to current locale's data.
Copyright (C) 1996, 1998, 2000, 2002, 2003 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stddef.h>
#include <stdlib.h>
#if ENABLE_NLS
# include <sys/types.h>
# include <limits.h>
# include <regex.h>
# include "gettext.h"
# define _(msgid) gettext (msgid)
static int
try (const char *response, const char *pattern, const int match,
const int nomatch, const char **lastp, regex_t *re)
{
if (pattern != *lastp)
{
/* The pattern has changed. */
if (*lastp)
{
/* Free the old compiled pattern. */
regfree (re);
*lastp = NULL;
}
/* Compile the pattern and cache it for future runs. */
if (regcomp (re, pattern, REG_EXTENDED) != 0)
return -1;
*lastp = pattern;
}
/* See if the regular expression matches RESPONSE. */
return regexec (re, response, 0, NULL, 0) == 0 ? match : nomatch;
}
#endif
int
rpmatch (const char *response)
{
#if ENABLE_NLS
/* Match against one of the response patterns, compiling the pattern
first if necessary. */
/* We cache the response patterns and compiled regexps here. */
static const char *yesexpr, *noexpr;
static regex_t yesre, nore;
int result;
return ((result = try (response, _("^[yY]"), 1, 0,
&yesexpr, &yesre))
? result
: try (response, _("^[nN]"), 0, -1, &noexpr, &nore));
#else
/* Test against "^[yY]" and "^[nN]", hardcoded to avoid requiring regex */
return (*response == 'y' || *response == 'Y' ? 1
: *response == 'n' || *response == 'N' ? 0 : -1);
#endif
}