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-rw-r--r--src/lib/libc/stdlib/setenv.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/src/lib/libc/stdlib/setenv.c b/src/lib/libc/stdlib/setenv.c
new file mode 100644
index 0000000000..2ba072b65c
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+++ b/src/lib/libc/stdlib/setenv.c
@@ -0,0 +1,118 @@
1/*
2 * Copyright (c) 1987 Regents of the University of California.
3 * 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 * 3. 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 *rcsid = "$OpenBSD: setenv.c,v 1.6 2003/06/02 20:18:38 millert Exp $";
32#endif /* LIBC_SCCS and not lint */
33
34#include <stdlib.h>
35#include <string.h>
36
37char *__findenv(const char *name, int *offset);
38
39/*
40 * setenv --
41 * Set the value of the environmental variable "name" to be
42 * "value". If rewrite is set, replace any current value.
43 */
44int
45setenv(name, value, rewrite)
46 register const char *name;
47 register const char *value;
48 int rewrite;
49{
50 extern char **environ;
51 static int alloced; /* if allocated space before */
52 register char *C;
53 int l_value, offset;
54
55 if (*value == '=') /* no `=' in value */
56 ++value;
57 l_value = strlen(value);
58 if ((C = __findenv(name, &offset))) { /* find if already exists */
59 if (!rewrite)
60 return (0);
61 if (strlen(C) >= l_value) { /* old larger; copy over */
62 while ((*C++ = *value++))
63 ;
64 return (0);
65 }
66 } else { /* create new slot */
67 register int cnt;
68 register char **P;
69
70 for (P = environ, cnt = 0; *P; ++P, ++cnt);
71 if (alloced) { /* just increase size */
72 P = (char **)realloc((void *)environ,
73 (size_t)(sizeof(char *) * (cnt + 2)));
74 if (!P)
75 return (-1);
76 environ = P;
77 }
78 else { /* get new space */
79 alloced = 1; /* copy old entries into it */
80 P = (char **)malloc((size_t)(sizeof(char *) *
81 (cnt + 2)));
82 if (!P)
83 return (-1);
84 bcopy(environ, P, cnt * sizeof(char *));
85 environ = P;
86 }
87 environ[cnt + 1] = NULL;
88 offset = cnt;
89 }
90 for (C = (char *)name; *C && *C != '='; ++C); /* no `=' in name */
91 if (!(environ[offset] = /* name + `=' + value */
92 malloc((size_t)((int)(C - name) + l_value + 2))))
93 return (-1);
94 for (C = environ[offset]; (*C = *name++) && *C != '='; ++C)
95 ;
96 for (*C++ = '='; (*C++ = *value++); )
97 ;
98 return (0);
99}
100
101/*
102 * unsetenv(name) --
103 * Delete environmental variable "name".
104 */
105void
106unsetenv(name)
107 const char *name;
108{
109 extern char **environ;
110 register char **P;
111 int offset;
112 char *__findenv();
113
114 while (__findenv(name, &offset)) /* if set multiple times */
115 for (P = &environ[offset];; ++P)
116 if (!(*P = *(P + 1)))
117 break;
118}