1/* Determine whether string value is affirmation or negative response
2   according to current locale's data.
3
4   Copyright (C) 1996, 1998, 2000, 2002, 2003, 2006 Free Software
5   Foundation, Inc.
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 2, or (at your option)
10   any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program; if not, write to the Free Software Foundation,
19   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
20
21#include <config.h>
22
23#include <stddef.h>
24#include <stdlib.h>
25
26#if ENABLE_NLS
27# include <sys/types.h>
28# include <limits.h>
29# include <regex.h>
30# include "gettext.h"
31# define _(msgid) gettext (msgid)
32
33static int
34try (const char *response, const char *pattern, const int match,
35     const int nomatch, const char **lastp, regex_t *re)
36{
37  if (pattern != *lastp)
38    {
39      /* The pattern has changed.  */
40      if (*lastp)
41	{
42	  /* Free the old compiled pattern.  */
43	  regfree (re);
44	  *lastp = NULL;
45	}
46      /* Compile the pattern and cache it for future runs.  */
47      if (regcomp (re, pattern, REG_EXTENDED) != 0)
48	return -1;
49      *lastp = pattern;
50    }
51
52  /* See if the regular expression matches RESPONSE.  */
53  return regexec (re, response, 0, NULL, 0) == 0 ? match : nomatch;
54}
55#endif
56
57
58int
59rpmatch (const char *response)
60{
61#if ENABLE_NLS
62  /* Match against one of the response patterns, compiling the pattern
63     first if necessary.  */
64
65  /* We cache the response patterns and compiled regexps here.  */
66  static const char *yesexpr, *noexpr;
67  static regex_t yesre, nore;
68  int result;
69
70  return ((result = try (response, _("^[yY]"), 1, 0,
71			 &yesexpr, &yesre))
72	  ? result
73	  : try (response, _("^[nN]"), 0, -1, &noexpr, &nore));
74#else
75  /* Test against "^[yY]" and "^[nN]", hardcoded to avoid requiring regex */
76  return (*response == 'y' || *response == 'Y' ? 1
77	  : *response == 'n' || *response == 'N' ? 0 : -1);
78#endif
79}
80