1/*
2 * Copyright (c) 1987, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)getenv.c	8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: src/lib/libc/stdlib/getenv.c,v 1.8 2007/05/01 16:02:41 ache Exp $");
35
36#include <stdlib.h>
37#include <stddef.h>
38#include <string.h>
39#include <crt_externs.h>
40
41__private_extern__ char *__findenv(const char *, int *, char **);
42
43/*
44 * __findenv --
45 *	Returns pointer to value associated with name, if any, else NULL.
46 *	Sets offset to be the offset of the name/value combination in the
47 *	environmental array, for use by setenv(3) and unsetenv(3).
48 *	Explicitly removes '=' in argument name.
49 *
50 *	This routine *should* be a static; don't use it.
51 */
52__private_extern__ char *
53__findenv(name, offset, environ)
54	const char *name;
55	int *offset;
56	char **environ;
57{
58	int len, i;
59	const char *np;
60	char **p, *cp;
61
62	if (name == NULL || environ == NULL)
63		return (NULL);
64	for (np = name; *np && *np != '='; ++np)
65		continue;
66	len = np - name;
67	for (p = environ; (cp = *p) != NULL; ++p) {
68		for (np = name, i = len; i && *cp; i--)
69			if (*cp++ != *np++)
70				break;
71		if (i == 0 && *cp++ == '=') {
72			*offset = p - environ;
73			return (cp);
74		}
75	}
76	return (NULL);
77}
78
79/*
80 * _getenvp -- SPI using an arbitrary pointer to string array (the array must
81 * have been created with malloc) and an env state, created by _allocenvstate().
82 *	Returns ptr to value associated with name, if any, else NULL.
83 */
84char *
85_getenvp(const char *name, char ***envp, void *state __unused)
86{
87	int offset;
88
89	return (__findenv(name, &offset, *envp));
90}
91
92/*
93 * getenv --
94 *	Returns ptr to value associated with name, if any, else NULL.
95 */
96char *
97getenv(name)
98	const char *name;
99{
100	int offset;
101
102	return (__findenv(name, &offset, *_NSGetEnviron()));
103}
104