1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* Copyright (C) 1992, 1995-2003, 2005-2010 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 /* Don't use __attribute__ __nonnull__ in this compilation unit. Otherwise gcc
24 optimizes away the name == NULL test below. */
25 #define _GL_ARG_NONNULL(params)
34 # define __set_errno(ev) ((errno) = (ev))
38 #if _LIBC || HAVE_UNISTD_H
46 #if _LIBC || !HAVE_SETENV
49 # define __environ environ
53 /* This lock protects against simultaneous modifications of `environ'. */
54 # include <bits/libc-lock.h>
55 __libc_lock_define_initialized (static, envlock)
56 # define LOCK __libc_lock_lock (envlock)
57 # define UNLOCK __libc_lock_unlock (envlock)
63 /* In the GNU C library we must keep the namespace clean. */
65 # define setenv __setenv
66 # define clearenv __clearenv
67 # define tfind __tfind
68 # define tsearch __tsearch
70 /* Use the system functions, not the gnulib overrides in this file. */
75 /* In the GNU C library implementation we try to be more clever and
76 allow arbitrarily many changes of the environment given that the used
77 values are from a small set. Outside glibc this will eat up all
78 memory after a while. */
79 #if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH \
81 # define USE_TSEARCH 1
83 typedef int (*compar_fn_t) (const void *, const void *);
85 /* This is a pointer to the root of the search tree with the known
87 static void *known_values;
89 # define KNOWN_VALUE(Str) \
91 void *value = tfind (Str, &known_values, (compar_fn_t) strcmp); \
92 value != NULL ? *(char **) value : NULL; \
94 # define STORE_VALUE(Str) \
95 tsearch (Str, &known_values, (compar_fn_t) strcmp)
100 # define KNOWN_VALUE(Str) NULL
101 # define STORE_VALUE(Str) do { } while (0)
106 /* If this variable is not a null pointer we allocated the current
108 static char **last_environ;
111 /* This function is used by `setenv' and `putenv'. The difference between
112 the two functions is that for the former must create a new string which
113 is then placed in the environment, while the argument of `putenv'
114 must be used directly. This is all complicated by the fact that we try
115 to reuse values once generated for a `setenv' call since we can never
118 __add_to_environ (const char *name, const char *value, const char *combined,
123 const size_t namelen = strlen (name);
124 const size_t vallen = value != NULL ? strlen (value) + 1 : 0;
128 /* We have to get the pointer now that we have the lock and not earlier
129 since another thread might have created a new environment. */
135 for (; *ep != NULL; ++ep)
136 if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
142 if (ep == NULL || *ep == NULL)
149 /* We allocated this space; we can extend it. */
151 (char **) (last_environ == NULL
152 ? malloc ((size + 2) * sizeof (char *))
153 : realloc (last_environ, (size + 2) * sizeof (char *)));
154 if (new_environ == NULL)
156 /* It's easier to set errno to ENOMEM than to rely on the
157 'malloc-posix' and 'realloc-posix' gnulib modules. */
158 __set_errno (ENOMEM);
163 /* If the whole entry is given add it. */
164 if (combined != NULL)
165 /* We must not add the string to the search tree since it belongs
167 new_environ[size] = (char *) combined;
170 /* See whether the value is already known. */
173 new_value = (char *) alloca (namelen + 1 + vallen);
174 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
177 new_value = (char *) malloca (namelen + 1 + vallen);
178 if (new_value == NULL)
180 __set_errno (ENOMEM);
184 memcpy (new_value, name, namelen);
185 new_value[namelen] = '=';
186 memcpy (&new_value[namelen + 1], value, vallen);
189 new_environ[size] = KNOWN_VALUE (new_value);
190 if (new_environ[size] == NULL)
193 new_environ[size] = (char *) malloc (namelen + 1 + vallen);
194 if (new_environ[size] == NULL)
196 #if defined USE_TSEARCH && !defined _LIBC
199 __set_errno (ENOMEM);
205 memcpy (new_environ[size], new_value, namelen + 1 + vallen);
207 memcpy (new_environ[size], name, namelen);
208 new_environ[size][namelen] = '=';
209 memcpy (&new_environ[size][namelen + 1], value, vallen);
211 /* And save the value now. We cannot do this when we remove
212 the string since then we cannot decide whether it is a
213 user string or not. */
214 STORE_VALUE (new_environ[size]);
216 #if defined USE_TSEARCH && !defined _LIBC
221 if (__environ != last_environ)
222 memcpy ((char *) new_environ, (char *) __environ,
223 size * sizeof (char *));
225 new_environ[size + 1] = NULL;
227 last_environ = __environ = new_environ;
233 /* Use the user string if given. */
234 if (combined != NULL)
235 np = (char *) combined;
241 new_value = alloca (namelen + 1 + vallen);
242 __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1),
245 new_value = malloca (namelen + 1 + vallen);
246 if (new_value == NULL)
248 __set_errno (ENOMEM);
252 memcpy (new_value, name, namelen);
253 new_value[namelen] = '=';
254 memcpy (&new_value[namelen + 1], value, vallen);
257 np = KNOWN_VALUE (new_value);
261 np = (char *) malloc (namelen + 1 + vallen);
264 #if defined USE_TSEARCH && !defined _LIBC
267 __set_errno (ENOMEM);
273 memcpy (np, new_value, namelen + 1 + vallen);
275 memcpy (np, name, namelen);
277 memcpy (&np[namelen + 1], value, vallen);
279 /* And remember the value. */
282 #if defined USE_TSEARCH && !defined _LIBC
296 setenv (const char *name, const char *value, int replace)
298 if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
300 __set_errno (EINVAL);
304 return __add_to_environ (name, value, NULL, replace);
307 /* The `clearenv' was planned to be added to POSIX.1 but probably
308 never made it. Nevertheless the POSIX.9 standard (POSIX bindings
309 for Fortran 77) requires this function. */
315 if (__environ == last_environ && __environ != NULL)
317 /* We allocated this environment so we can free it. */
322 /* Clear the environment pointer removes the whole environment. */
334 /* Remove all traces. */
337 /* Now remove the search tree. */
338 __tdestroy (known_values, free);
341 text_set_element (__libc_subfreeres, free_mem);
346 weak_alias (__setenv, setenv)
347 weak_alias (__clearenv, clearenv)
350 #endif /* _LIBC || !HAVE_SETENV */
352 /* The rest of this file is called into use when replacing an existing
353 but buggy setenv. Known bugs include failure to diagnose invalid
354 name, and consuming a leading '=' from value. */
358 # define STREQ(a, b) (strcmp (a, b) == 0)
361 rpl_setenv (const char *name, const char *value, int replace)
364 if (!name || !*name || strchr (name, '='))
369 /* Call the real setenv even if replace is 0, in case implementation
370 has underlying data to update, such as when environ changes. */
371 result = setenv (name, value, replace);
372 if (result == 0 && replace && *value == '=')
374 char *tmp = getenv (name);
375 if (!STREQ (tmp, value))
378 size_t len = strlen (value);
379 tmp = malloca (len + 2);
380 /* Since leading '=' is eaten, double it up. */
382 memcpy (tmp + 1, value, len + 1);
383 result = setenv (name, tmp, replace);
392 #endif /* HAVE_SETENV */