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
23 #include <gpg-error.h>
24 #define __set_errno(ev) (gpg_err_set_errno (ev))
27 /* Fixme: Why do we need to include the assuan header and why the
29 #include "assuan-defs.h"
30 #endif /*HAVE_ASSUAN_H*/
32 #define __builtin_expect(cond,val) (cond)
36 #if _LIBC || HAVE_STDLIB_H
39 #if _LIBC || HAVE_STRING_H
42 #if _LIBC || HAVE_UNISTD_H
47 # define __environ environ
48 # ifndef HAVE_ENVIRON_DECL
49 extern char **environ;
54 /* This lock protects against simultaneous modifications of `environ'. */
55 # include <bits/libc-lock.h>
56 __libc_lock_define_initialized (static, envlock)
57 # define LOCK __libc_lock_lock (envlock)
58 # define UNLOCK __libc_lock_unlock (envlock)
64 /* In the GNU C library we must keep the namespace clean. */
66 # define setenv __setenv
67 # define unsetenv __unsetenv
68 # define clearenv __clearenv
69 # define tfind __tfind
70 # define tsearch __tsearch
73 /* In the GNU C library implementation we try to be more clever and
74 allow arbitrarily many changes of the environment given that the used
75 values are from a small set. Outside glibc this will eat up all
76 memory after a while. */
77 #if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH \
79 # define USE_TSEARCH 1
82 /* This is a pointer to the root of the search tree with the known
84 static void *known_values;
86 # define KNOWN_VALUE(Str) \
88 void *value = tfind (Str, &known_values, (__compar_fn_t) strcmp); \
89 value != NULL ? *(char **) value : NULL; \
91 # define STORE_VALUE(Str) \
92 tsearch (Str, &known_values, (__compar_fn_t) strcmp)
97 # define KNOWN_VALUE(Str) NULL
98 # define STORE_VALUE(Str) do { } while (0)
103 /* If this variable is not a null pointer we allocated the current
105 static char **last_environ;
108 /* This function is used by `setenv' and `putenv'. The difference between
109 the two functions is that for the former must create a new string which
110 is then placed in the environment, while the argument of `putenv'
111 must be used directly. This is all complicated by the fact that we try
112 to reuse values once generated for a `setenv' call since we can never
115 __add_to_environ (const char *name, const char *value, const char *combined,
119 register size_t size;
120 const size_t namelen = strlen (name);
121 const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
125 /* We have to get the pointer now that we have the lock and not earlier
126 since another thread might have created a new environment. */
132 for (; *ep != NULL; ++ep)
133 if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
139 if (ep == NULL || __builtin_expect (*ep == NULL, 1))
143 /* We allocated this space; we can extend it. */
144 new_environ = (char **) realloc (last_environ,
145 (size + 2) * sizeof (char *));
146 if (new_environ == NULL)
152 /* If the whole entry is given add it. */
153 if (combined != NULL)
154 /* We must not add the string to the search tree since it belongs
156 new_environ[size] = (char *) combined;
159 /* See whether the value is already known. */
162 char new_value[namelen + 1 + vallen];
164 char *new_value = (char *) alloca (namelen + 1 + vallen);
167 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
170 memcpy (new_value, name, namelen);
171 new_value[namelen] = '=';
172 memcpy (&new_value[namelen + 1], value, vallen);
175 new_environ[size] = KNOWN_VALUE (new_value);
176 if (__builtin_expect (new_environ[size] == NULL, 1))
179 new_environ[size] = (char *) malloc (namelen + 1 + vallen);
180 if (__builtin_expect (new_environ[size] == NULL, 0))
182 __set_errno (ENOMEM);
188 memcpy (new_environ[size], new_value, namelen + 1 + vallen);
190 memcpy (new_environ[size], name, namelen);
191 new_environ[size][namelen] = '=';
192 memcpy (&new_environ[size][namelen + 1], value, vallen);
194 /* And save the value now. We cannot do this when we remove
195 the string since then we cannot decide whether it is a
196 user string or not. */
197 STORE_VALUE (new_environ[size]);
201 if (__environ != last_environ)
202 memcpy ((char *) new_environ, (char *) __environ,
203 size * sizeof (char *));
205 new_environ[size + 1] = NULL;
207 last_environ = __environ = new_environ;
213 /* Use the user string if given. */
214 if (combined != NULL)
215 np = (char *) combined;
220 char new_value[namelen + 1 + vallen];
222 char *new_value = (char *) alloca (namelen + 1 + vallen);
225 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
228 memcpy (new_value, name, namelen);
229 new_value[namelen] = '=';
230 memcpy (&new_value[namelen + 1], value, vallen);
233 np = KNOWN_VALUE (new_value);
234 if (__builtin_expect (np == NULL, 1))
237 np = malloc (namelen + 1 + vallen);
238 if (__builtin_expect (np == NULL, 0))
245 memcpy (np, new_value, namelen + 1 + vallen);
247 memcpy (np, name, namelen);
249 memcpy (&np[namelen + 1], value, vallen);
251 /* And remember the value. */
265 setenv (const char *name, const char *value, int replace)
267 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
269 __set_errno (EINVAL);
273 return __add_to_environ (name, value, NULL, replace);
277 unsetenv (const char *name)
282 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
284 __set_errno (EINVAL);
294 if (!strncmp (*ep, name, len) && (*ep)[len] == '=')
296 /* Found it. Remove this pointer by moving later ones back. */
302 /* Continue the loop in case NAME appears again. */
312 /* The `clearenv' was planned to be added to POSIX.1 but probably
313 never made it. Nevertheless the POSIX.9 standard (POSIX bindings
314 for Fortran 77) requires this function. */
320 if (__environ == last_environ && __environ != NULL)
322 /* We allocated this environment so we can free it. */
327 /* Clear the environment pointer removes the whole environment. */
335 libc_freeres_fn (free_mem)
337 /* Remove all traces. */
340 /* Now remove the search tree. */
341 __tdestroy (known_values, free);
348 weak_alias (__setenv, setenv)
349 weak_alias (__unsetenv, unsetenv)
350 weak_alias (__clearenv, clearenv)