1 /* $NetBSD: putenv.c,v 1.2 2017/01/28 21:31:50 christos Exp $ */
2
3 /*
4 * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
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 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <config.h>
37
38 #include <stdlib.h>
39
40 #if !HAVE_DECL_ENVIRON
41 extern char **environ;
42 #endif
43
44 /*
45 * putenv --
46 * String points to a string of the form name=value.
47 *
48 * Makes the value of the environment variable name equal to
49 * value by altering an existing variable or creating a new one.
50 */
51
52 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
putenv(const char * string)53 putenv(const char *string)
54 {
55 int i;
56 const char *eq = (const char *)strchr(string, '=');
57 int len;
58
59 if (eq == NULL)
60 return 1;
61 len = eq - string;
62
63 if(environ == NULL) {
64 environ = malloc(sizeof(char*));
65 if(environ == NULL)
66 return 1;
67 environ[0] = NULL;
68 }
69
70 for(i = 0; environ[i] != NULL; i++)
71 if(strncmp(string, environ[i], len) == 0) {
72 environ[i] = string;
73 return 0;
74 }
75 environ = realloc(environ, sizeof(char*) * (i + 2));
76 if(environ == NULL)
77 return 1;
78 environ[i] = string;
79 environ[i+1] = NULL;
80 return 0;
81 }
82