1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
/* Copyright (C) 1992, 1995, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#if _LIBC || HAVE_STDLIB_H
# include <stdlib.h>
#endif
#if _LIBC || HAVE_STRING_H
# include <string.h>
#endif
#if _LIBC || HAVE_UNISTD_H
# include <unistd.h>
#endif
#if _LIBC - 0 == 0
# define __environ environ
#endif
#if _LIBC - 0
/* This lock protects against simultaneous modifications of `environ'. */
# include <libc-lock.h>
__libc_lock_define_initialized (static, envlock)
# define LOCK __libc_lock_lock (envlock)
# define UNLOCK __libc_lock_unlock (envlock)
#else
# define LOCK
# define UNLOCK
#endif
/* If this variable is not a null pointer we allocated the current
environment. */
static char **last_environ;
int
setenv (name, value, replace)
const char *name;
const char *value;
int replace;
{
register char **ep;
register size_t size;
const size_t namelen = strlen (name);
const size_t vallen = strlen (value) + 1;
LOCK;
size = 0;
if (__environ != NULL)
for (ep = __environ; *ep != NULL; ++ep)
if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
break;
else
++size;
if (__environ == NULL || *ep == NULL)
{
char **new_environ;
if (__environ == last_environ && __environ != NULL)
/* We allocated this space; we can extend it. */
new_environ = (char **) realloc (last_environ,
(size + 2) * sizeof (char *));
else
new_environ = (char **) malloc ((size + 2) * sizeof (char *));
if (new_environ == NULL)
{
UNLOCK;
return -1;
}
new_environ[size] = malloc (namelen + 1 + vallen);
if (new_environ[size] == NULL)
{
free ((char *) new_environ);
__set_errno (ENOMEM);
UNLOCK;
return -1;
}
if (__environ != last_environ)
memcpy ((char *) new_environ, (char *) __environ,
size * sizeof (char *));
memcpy (new_environ[size], name, namelen);
new_environ[size][namelen] = '=';
memcpy (&new_environ[size][namelen + 1], value, vallen);
new_environ[size + 1] = NULL;
last_environ = __environ = new_environ;
}
else if (replace)
{
size_t len = strlen (*ep);
if (len + 1 < namelen + 1 + vallen)
{
/* The existing string is too short; malloc a new one. */
char *new = malloc (namelen + 1 + vallen);
if (new == NULL)
{
UNLOCK;
return -1;
}
*ep = new;
}
memcpy (*ep, name, namelen);
(*ep)[namelen] = '=';
memcpy (&(*ep)[namelen + 1], value, vallen);
}
UNLOCK;
return 0;
}
void
unsetenv (name)
const char *name;
{
const size_t len = strlen (name);
char **ep;
LOCK;
for (ep = __environ; *ep; ++ep)
if (!strncmp (*ep, name, len) && (*ep)[len] == '=')
{
/* Found it. Remove this pointer by moving later ones back. */
char **dp = ep;
do
dp[0] = dp[1];
while (*dp++);
/* Continue the loop in case NAME appears again. */
}
UNLOCK;
}
/* The `clearenv' was planned to be added to POSIX.1 but probably
never made it. Nevertheless the POSIX.9 standard (POSIX bindings
for Fortran 77) requires this function. */
int
clearenv ()
{
LOCK;
if (__environ == last_environ && __environ != NULL)
{
/* We allocated this environment so we can free it. */
free (__environ);
last_environ = NULL;
}
/* Clear the environment pointer removes the whole environment. */
__environ = NULL;
UNLOCK;
return 0;
}
|
GitWeb