-/* Copyright (C) 1992, 1995 Free Software Foundation, Inc.
-This file is part of the GNU C Library.
+/* Copyright (C) 1992,95,96,97,98,99,2000,2001 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 free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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.
+ 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
+ Lesser 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., 675 Mass Ave,
-Cambridge, MA 02139, USA. */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA.
+ modified for uClibc by Erik Andersen <andersen@codepoet.org>
+*/
+
+#include <features.h>
+#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-#include <errno.h>
-#if !defined(HAVE_GNU_LD) && !defined (__ELF__)
-#define __environ environ
-#endif
-#if defined(_REENTRENT) || defined(_THREAD_SAFE)
-# include <pthread.h>
+#include <bits/uClibc_mutex.h>
+__UCLIBC_MUTEX_STATIC(mylock, PTHREAD_MUTEX_INITIALIZER);
-/* We need to initialize the mutex. For this we use a method provided
- by pthread function 'pthread_once'. For this we need a once block. */
-static pthread_once__t _once_block = pthread_once_init;
-/* This is the mutex which protects the global environment of simultaneous
- modifications. */
-static pthread_mutex_t _setenv_mutex;
+/* If this variable is not a null pointer we allocated the current
+ environment. */
+static char **last_environ;
-static void
-DEFUN_VOID(_init_setenv_mutex)
+
+/* This function is used by `setenv' and `putenv'. The difference between
+ the two functions is that for the former must create a new string which
+ is then placed in the environment, while the argument of `putenv'
+ must be used directly. This is all complicated by the fact that we try
+ to reuse values once generated for a `setenv' call since we can never
+ free the strings. [in uclibc, we do not] */
+static int __add_to_environ(const char *name, const char *value,
+ int replace)
{
- pthread_mutex_init(&_setenv_mutex, pthread_mutexattr_default);
-}
+ register char **ep;
+ register size_t size;
+ char *var_val;
+ char **new_environ;
+ /* name may come from putenv() and thus may contain "=VAL" part */
+ const size_t namelen = strchrnul(name, '=') - name;
+ int rv = -1;
+
+ __UCLIBC_MUTEX_LOCK(mylock);
+
+ /* We have to get the pointer now that we have the lock and not earlier
+ since another thread might have created a new environment. */
+ ep = __environ;
+
+ size = 0;
+ if (ep != NULL) {
+ while (*ep != NULL) {
+ if (!strncmp(*ep, name, namelen) && (*ep)[namelen] == '=') {
+ /* Found */
+ if (!replace)
+ goto DONE_OK;
+ goto REPLACE;
+ }
+ ++size;
+ ++ep;
+ }
+ }
-# define LOCK() \
- do { pthread_once(&_once_block, _init_setenv_mutex);
- pthread_mutex_lock(&_setenv_mutex); } while (0)
-# define UNLOCK() pthread_mutex_unlock(&_setenv_mutex)
+ /* Not found, add at the end */
-#else /* !_REENTRENT && !_THREAD_SAFE */
+ /* We allocated this space; we can extend it. */
+ new_environ = realloc(last_environ, (size + 2) * sizeof(char *));
+ if (new_environ == NULL) {
+ __set_errno(ENOMEM);
+ goto DONE;
+ }
+ if (__environ != last_environ) {
+ memcpy(new_environ, __environ, size * sizeof(char *));
+ }
+ last_environ = __environ = new_environ;
+
+ ep = &new_environ[size];
+ /* Ensure env is NULL terminated in case malloc below fails */
+ ep[0] = NULL;
+ ep[1] = NULL;
+
+ REPLACE:
+ var_val = (char*) name;
+ /* Build VAR=VAL if we called by setenv, not putenv. */
+ if (value != NULL) {
+ const size_t vallen = strlen(value) + 1;
+
+ var_val = malloc(namelen + 1 + vallen);
+ if (var_val == NULL) {
+ __set_errno(ENOMEM);
+ goto DONE;
+ }
+ memcpy(var_val, name, namelen);
+ var_val[namelen] = '=';
+ memcpy(&var_val[namelen + 1], value, vallen);
+ }
+ *ep = var_val;
-# define LOCK()
-# define UNLOCK()
+ DONE_OK:
+ rv = 0;
-#endif /* _REENTRENT || _THREAD_SAFE */
+ DONE:
+ __UCLIBC_MUTEX_UNLOCK(mylock);
+ return rv;
+}
int setenv(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);
- int result = 0;
-
- LOCK();
-
- size = 0;
- for (ep = __environ; *ep != NULL; ++ep)
- if (!memcmp (*ep, name, namelen) && (*ep)[namelen] == '=')
- break;
- else
- ++size;
-
- if (*ep == NULL)
- {
- static char **last_environ = NULL;
- char **new_environ = (char **) malloc((size + 2) * sizeof(char *));
- if (new_environ == NULL)
- {
- result = -1;
- goto do_return;
- }
- (void) memcpy((__ptr_t) new_environ, (__ptr_t) __environ, size * sizeof(char *));
-
- new_environ[size] = malloc (namelen + 1 + vallen + 1);
- if (new_environ[size] == NULL)
- {
- free (new_environ);
- errno = ENOMEM;
- result = -1;
- goto do_return;
+ /* NB: setenv("VAR", NULL, 1) inserts "VAR=" string */
+ return __add_to_environ(name, value ? value : "", replace);
+}
+libc_hidden_def(setenv)
+
+int unsetenv(const char *name)
+{
+ const char *eq;
+ size_t len;
+ char **ep;
+
+ if (name == NULL || *name == '\0'
+ || *(eq = strchrnul(name, '=')) == '='
+ ) {
+ __set_errno(EINVAL);
+ return -1;
}
- memcpy (new_environ[size], name, namelen);
- new_environ[size][namelen] = '=';
- memcpy (&new_environ[size][namelen + 1], value, vallen + 1);
-
- new_environ[size + 1] = NULL;
-
- if (last_environ != NULL)
- free ((__ptr_t) last_environ);
- last_environ = new_environ;
- __environ = new_environ;
- }
- else if (replace)
- {
- size_t len = strlen (*ep);
- if (len < namelen + 1 + vallen)
- {
- char *new = malloc (namelen + 1 + vallen + 1);
- if (new == NULL)
- {
- result = -1;
- goto do_return;
- }
- *ep = new;
- memcpy (*ep, name, namelen);
- (*ep)[namelen] = '=';
+ len = eq - name; /* avoiding strlen this way */
+
+ __UCLIBC_MUTEX_LOCK(mylock);
+ ep = __environ;
+ /* NB: clearenv(); unsetenv("foo"); should not segfault */
+ if (ep) while (*ep != NULL) {
+ 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. */
+ } else {
+ ++ep;
+ }
}
- memcpy (&(*ep)[namelen + 1], value, vallen + 1);
- }
-
-do_return:
- UNLOCK();
- return result;
+ __UCLIBC_MUTEX_UNLOCK(mylock);
+ return 0;
}
+libc_hidden_def(unsetenv)
-
-void unsetenv(const char *name)
+/* 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(void)
{
- register char **ep;
- register char **dp;
- const size_t namelen = strlen (name);
-
- LOCK();
-
- for (dp = ep = __environ; *ep != NULL; ++ep)
- if (memcmp (*ep, name, namelen) || (*ep)[namelen] != '=')
- {
- *dp = *ep;
- ++dp;
- }
- *dp = NULL;
+ __UCLIBC_MUTEX_LOCK(mylock);
+ /* If we allocated this environment we can free it.
+ * If we did not allocate this environment, it's NULL already
+ * and is safe to free(). */
+ free(last_environ);
+ last_environ = NULL;
+ /* Clearing environ removes the whole environment. */
+ __environ = NULL;
+ __UCLIBC_MUTEX_UNLOCK(mylock);
+ return 0;
+}
- UNLOCK();
+/* Put STRING, which is of the form "NAME=VALUE", in the environment. */
+int putenv(char *string)
+{
+ if (strchr(string, '=') != NULL) {
+ return __add_to_environ(string, NULL, 1);
+ }
+ return unsetenv(string);
}
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