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-rw-r--r--sysdeps/generic/setenv.c92
1 files changed, 60 insertions, 32 deletions
diff --git a/sysdeps/generic/setenv.c b/sysdeps/generic/setenv.c
index 44830e9aa7..9403ccb035 100644
--- a/sysdeps/generic/setenv.c
+++ b/sysdeps/generic/setenv.c
@@ -1,52 +1,57 @@
 /* Copyright (C) 1992, 1995, 1996 Free Software Foundation, Inc.
-This file is part of the GNU C Library.
+   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 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 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
+   Library 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 Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
 
-#ifdef HAVE_CONFIG_H
-#include <config.h>
+#if HAVE_CONFIG_H
+# include <config.h>
 #endif
 
 #include <errno.h>
 
 #if _LIBC || HAVE_STDLIB_H
-#include <stdlib.h>
+# include <stdlib.h>
 #endif
 #if _LIBC || HAVE_STRING_H
-#include <string.h>
+# include <string.h>
 #endif
 #if _LIBC || HAVE_UNISTD_H
-#include <unistd.h>
+# include <unistd.h>
 #endif
 
 #if _LIBC - 0 == 0
-#define	__environ	environ
+# define __environ	environ
 #endif
 
 #if _LIBC - 0
 /* This lock protects against simultaneous modifications of `environ'.  */
-#include <libc-lock.h>
+# include <libc-lock.h>
 __libc_lock_define_initialized (static, envlock)
-#define LOCK	__libc_lock_lock (envlock)
-#define UNLOCK	__libc_lock_unlock (envlock)
+# define LOCK	__libc_lock_lock (envlock)
+# define UNLOCK	__libc_lock_unlock (envlock)
 #else
-#define LOCK
-#define UNLOCK
+# define LOCK
+# define UNLOCK
 #endif
 
+/* If this variable is not a null pointer we allocated the current
+   environment.  */
+static char **last_environ;
+
+
 int
 setenv (name, value, replace)
      const char *name;
@@ -61,17 +66,17 @@ setenv (name, value, replace)
   LOCK;
 
   size = 0;
-  for (ep = __environ; *ep != NULL; ++ep)
-    if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
-      break;
-    else
-      ++size;
+  if (__environ != NULL)
+    for (ep = __environ; *ep != NULL; ++ep)
+      if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
+	break;
+      else
+	++size;
 
-  if (*ep == NULL)
+  if (__environ == NULL || *ep == NULL)
     {
-      static char **last_environ;
       char **new_environ;
-      if (__environ == last_environ)
+      if (__environ == last_environ && __environ != NULL)
 	/* We allocated this space; we can extend it.  */
 	new_environ = (char **) realloc (last_environ,
 					 (size + 2) * sizeof (char *));
@@ -151,3 +156,26 @@ unsetenv (name)
 
   UNLOCK;
 }
+
+/* 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 ()
+{
+  LOCK;
+
+  if (__environ == last_environ && __environ != NULL)
+    {
+      /* We allocated this environment so we can free it.  */
+      free (__environ);
+      last_environ = NULL;
+    }
+
+  /* Clear the environment pointer removes the whole environment.  */
+  __environ = NULL;
+
+  UNLOCK;
+
+  return 0;
+}