1 /* Copyright (C) 1992,1995-2001,2004 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
24 #include <gpg-error.h>
25 #define __set_errno(ev) (gpg_err_set_errno (ev))
28 /* Fixme: Why do we need to include the assuan header and why the
30 #include "assuan-defs.h"
31 #endif /*HAVE_ASSUAN_H*/
33 #define __builtin_expect(cond,val) (cond)
37 #if _LIBC || HAVE_STDLIB_H
40 #if _LIBC || HAVE_STRING_H
43 #if _LIBC || HAVE_UNISTD_H
48 # define __environ environ
49 # ifndef HAVE_ENVIRON_DECL
50 extern char **environ;
55 /* This lock protects against simultaneous modifications of `environ'. */
56 # include <bits/libc-lock.h>
57 __libc_lock_define_initialized (static, envlock)
58 # define LOCK __libc_lock_lock (envlock)
59 # define UNLOCK __libc_lock_unlock (envlock)
65 /* In the GNU C library we must keep the namespace clean. */
67 # define setenv __setenv
68 # define unsetenv __unsetenv
69 # define clearenv __clearenv
70 # define tfind __tfind
71 # define tsearch __tsearch
74 /* In the GNU C library implementation we try to be more clever and
75 allow arbitrarily many changes of the environment given that the used
76 values are from a small set. Outside glibc this will eat up all
77 memory after a while. */
78 #if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH \
80 # define USE_TSEARCH 1
83 /* This is a pointer to the root of the search tree with the known
85 static void *known_values;
87 # define KNOWN_VALUE(Str) \
89 void *value = tfind (Str, &known_values, (__compar_fn_t) strcmp); \
90 value != NULL ? *(char **) value : NULL; \
92 # define STORE_VALUE(Str) \
93 tsearch (Str, &known_values, (__compar_fn_t) strcmp)
98 # define KNOWN_VALUE(Str) NULL
99 # define STORE_VALUE(Str) do { } while (0)
104 /* If this variable is not a null pointer we allocated the current
106 static char **last_environ;
109 /* This function is used by `setenv' and `putenv'. The difference between
110 the two functions is that for the former must create a new string which
111 is then placed in the environment, while the argument of `putenv'
112 must be used directly. This is all complicated by the fact that we try
113 to reuse values once generated for a `setenv' call since we can never
116 __add_to_environ (const char *name, const char *value, const char *combined,
120 register size_t size;
121 const size_t namelen = strlen (name);
122 const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
126 /* We have to get the pointer now that we have the lock and not earlier
127 since another thread might have created a new environment. */
133 for (; *ep != NULL; ++ep)
134 if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
140 if (ep == NULL || __builtin_expect (*ep == NULL, 1))
144 /* We allocated this space; we can extend it. */
145 new_environ = (char **) realloc (last_environ,
146 (size + 2) * sizeof (char *));
147 if (new_environ == NULL)
153 /* If the whole entry is given add it. */
154 if (combined != NULL)
155 /* We must not add the string to the search tree since it belongs
157 new_environ[size] = (char *) combined;
160 /* See whether the value is already known. */
163 char new_value[namelen + 1 + vallen];
165 char *new_value = (char *) alloca (namelen + 1 + vallen);
168 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
171 memcpy (new_value, name, namelen);
172 new_value[namelen] = '=';
173 memcpy (&new_value[namelen + 1], value, vallen);
176 new_environ[size] = KNOWN_VALUE (new_value);
177 if (__builtin_expect (new_environ[size] == NULL, 1))
180 new_environ[size] = (char *) malloc (namelen + 1 + vallen);
181 if (__builtin_expect (new_environ[size] == NULL, 0))
183 __set_errno (ENOMEM);
189 memcpy (new_environ[size], new_value, namelen + 1 + vallen);
191 memcpy (new_environ[size], name, namelen);
192 new_environ[size][namelen] = '=';
193 memcpy (&new_environ[size][namelen + 1], value, vallen);
195 /* And save the value now. We cannot do this when we remove
196 the string since then we cannot decide whether it is a
197 user string or not. */
198 STORE_VALUE (new_environ[size]);
202 if (__environ != last_environ)
203 memcpy ((char *) new_environ, (char *) __environ,
204 size * sizeof (char *));
206 new_environ[size + 1] = NULL;
208 last_environ = __environ = new_environ;
214 /* Use the user string if given. */
215 if (combined != NULL)
216 np = (char *) combined;
221 char new_value[namelen + 1 + vallen];
223 char *new_value = (char *) alloca (namelen + 1 + vallen);
226 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
229 memcpy (new_value, name, namelen);
230 new_value[namelen] = '=';
231 memcpy (&new_value[namelen + 1], value, vallen);
234 np = KNOWN_VALUE (new_value);
235 if (__builtin_expect (np == NULL, 1))
238 np = malloc (namelen + 1 + vallen);
239 if (__builtin_expect (np == NULL, 0))
246 memcpy (np, new_value, namelen + 1 + vallen);
248 memcpy (np, name, namelen);
250 memcpy (&np[namelen + 1], value, vallen);
252 /* And remember the value. */
266 setenv (const char *name, const char *value, int replace)
268 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
270 __set_errno (EINVAL);
274 return __add_to_environ (name, value, NULL, replace);
278 unsetenv (const char *name)
283 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
285 __set_errno (EINVAL);
295 if (!strncmp (*ep, name, len) && (*ep)[len] == '=')
297 /* Found it. Remove this pointer by moving later ones back. */
303 /* Continue the loop in case NAME appears again. */
313 /* The `clearenv' was planned to be added to POSIX.1 but probably
314 never made it. Nevertheless the POSIX.9 standard (POSIX bindings
315 for Fortran 77) requires this function. */
321 if (__environ == last_environ && __environ != NULL)
323 /* We allocated this environment so we can free it. */
328 /* Clear the environment pointer removes the whole environment. */
336 libc_freeres_fn (free_mem)
338 /* Remove all traces. */
341 /* Now remove the search tree. */
342 __tdestroy (known_values, free);
349 weak_alias (__setenv, setenv)
350 weak_alias (__unsetenv, unsetenv)
351 weak_alias (__clearenv, clearenv)