This source file includes following definitions.
- _unsetenv
- putenv
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20 #include <config.h>
21
22
23 #include <stdlib.h>
24
25 #include <stddef.h>
26
27
28
29 #include <errno.h>
30 #ifndef __set_errno
31 # define __set_errno(ev) ((errno) = (ev))
32 #endif
33
34 #include <string.h>
35 #include <unistd.h>
36
37 #if defined _WIN32 && ! defined __CYGWIN__
38 # define WIN32_LEAN_AND_MEAN
39 # include <windows.h>
40 #endif
41
42 #if _LIBC
43 # if HAVE_GNU_LD
44 # define environ __environ
45 # else
46 extern char **environ;
47 # endif
48 #endif
49
50 #if _LIBC
51
52 # include <bits/libc-lock.h>
53 __libc_lock_define_initialized (static, envlock)
54 # define LOCK __libc_lock_lock (envlock)
55 # define UNLOCK __libc_lock_unlock (envlock)
56 #else
57 # define LOCK
58 # define UNLOCK
59 #endif
60
61 #if defined _WIN32 && ! defined __CYGWIN__
62
63 # undef SetEnvironmentVariable
64 # define SetEnvironmentVariable SetEnvironmentVariableA
65 #endif
66
67 static int
68 _unsetenv (const char *name)
69 {
70 size_t len;
71 #if !HAVE_DECL__PUTENV
72 char **ep;
73 #endif
74
75 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
76 {
77 __set_errno (EINVAL);
78 return -1;
79 }
80
81 len = strlen (name);
82
83 #if HAVE_DECL__PUTENV
84 {
85 int putenv_result;
86 char *name_ = malloc (len + 2);
87 memcpy (name_, name, len);
88 name_[len] = '=';
89 name_[len + 1] = 0;
90 putenv_result = _putenv (name_);
91 free (name_);
92 return putenv_result;
93 }
94 #else
95
96 LOCK;
97
98 ep = environ;
99 while (*ep != NULL)
100 if (!strncmp (*ep, name, len) && (*ep)[len] == '=')
101 {
102
103 char **dp = ep;
104
105 do
106 dp[0] = dp[1];
107 while (*dp++);
108
109 }
110 else
111 ++ep;
112
113 UNLOCK;
114
115 return 0;
116 #endif
117 }
118
119
120
121
122 int
123 putenv (char *string)
124 {
125 const char *name_end = strchr (string, '=');
126 char **ep;
127
128 if (name_end == NULL)
129 {
130
131 return _unsetenv (string);
132 }
133
134 #if HAVE_DECL__PUTENV
135
136
137
138 if (name_end[1])
139 return _putenv (string);
140 else
141 {
142
143
144
145 int putenv_result;
146 char *name_x = malloc (name_end - string + sizeof "= ");
147 if (!name_x)
148 return -1;
149 memcpy (name_x, string, name_end - string + 1);
150 name_x[name_end - string + 1] = ' ';
151 name_x[name_end - string + 2] = 0;
152 putenv_result = _putenv (name_x);
153 for (ep = environ; *ep; ep++)
154 if (strcmp (*ep, name_x) == 0)
155 {
156 *ep = string;
157 break;
158 }
159 # if defined _WIN32 && ! defined __CYGWIN__
160 if (putenv_result == 0)
161 {
162
163
164 name_x[name_end - string] = 0;
165 putenv_result = SetEnvironmentVariable (name_x, "") ? 0 : -1;
166 errno = ENOMEM;
167 }
168 # endif
169 free (name_x);
170 return putenv_result;
171 }
172 #else
173 for (ep = environ; *ep; ep++)
174 if (strncmp (*ep, string, name_end - string) == 0
175 && (*ep)[name_end - string] == '=')
176 break;
177
178 if (*ep)
179 *ep = string;
180 else
181 {
182 static char **last_environ = NULL;
183 size_t size = ep - environ;
184 char **new_environ = malloc ((size + 2) * sizeof *new_environ);
185 if (! new_environ)
186 return -1;
187 new_environ[0] = string;
188 memcpy (new_environ + 1, environ, (size + 1) * sizeof *new_environ);
189 free (last_environ);
190 last_environ = new_environ;
191 environ = new_environ;
192 }
193
194 return 0;
195 #endif
196 }