1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1992 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * James da Silva at the University of Maryland at College Park.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD$");
37__SCCSID("@(#)regex.c	5.1 (Berkeley) 3/29/92");
38
39/*
40 * Compatibility routines that implement the old re_comp/re_exec interface in
41 * terms of the regcomp/regexec interface.  It's possible that some programs
42 * rely on dark corners of re_comp/re_exec and won't work with this version,
43 * but most programs should be fine.
44 */
45
46#include <regex.h>
47#include <stddef.h>
48#include <unistd.h>
49
50static regex_t re_regexp;
51static int re_gotexp;
52static char re_errstr[100];
53
54char *
55re_comp(const char *s)
56{
57	int rc;
58
59	if (s == NULL || *s == '\0') {
60		if (!re_gotexp)
61			return __DECONST(char *,
62			    "no previous regular expression");
63		return (NULL);
64	}
65
66	if (re_gotexp) {
67		regfree(&re_regexp);
68		re_gotexp = 0;
69	}
70
71	rc = regcomp(&re_regexp, s, REG_EXTENDED);
72	if (rc == 0) {
73		re_gotexp = 1;
74		return (NULL);
75	}
76
77	regerror(rc, &re_regexp, re_errstr, sizeof(re_errstr));
78	re_errstr[sizeof(re_errstr) - 1] = '\0';
79	return (re_errstr);
80}
81
82int
83re_exec(const char *s)
84{
85	int rc;
86
87	if (!re_gotexp)
88		return (-1);
89	rc = regexec(&re_regexp, s, 0, NULL, 0);
90	return (rc == 0 ? 1 : 0);
91}
92