1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /* Copyright (c) 1984 AT&T */
23 /* All Rights Reserved */
24
25 #pragma ident "%Z%%M% %I% %E% SMI" /* from S5R2 1.2 */
26
27 /*LINTLIBRARY*/
28 /*
29 * getenv(name)
30 * returns ptr to value associated with name, if any, else NULL
31 */
32 #define NULL 0
33 extern char **environ;
34 static char *nvmatch();
35
36 char *
getenv(name)37 getenv(name)
38 register char *name;
39 {
40 register char *v, **p=environ;
41
42 if(p == NULL)
43 return(NULL);
44 while(*p != NULL)
45 if((v = nvmatch(name, *p++)) != NULL)
46 return(v);
47 return(NULL);
48 }
49
50 /*
51 * s1 is either name, or name=value
52 * s2 is name=value
53 * if names match, return value of s2, else NULL
54 * used for environment searching: see getenv
55 */
56
57 static char *
nvmatch(s1,s2)58 nvmatch(s1, s2)
59 register char *s1, *s2;
60 {
61 while(*s1 == *s2++)
62 if(*s1++ == '=')
63 return(s2);
64 if(*s1 == '\0' && *(s2-1) == '=')
65 return(s2);
66 return(NULL);
67 }
68