X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fputenv.c;h=1c097ccc47e9e53bb000e6f72c6c82bb32e675a9;hb=49d9742daf6fc7cf638b621ab6066fb1f72cfccc;hp=58a498fdaa478994071938fb5765c9e2e503e358;hpb=d08d65270f19fbeff7b0194da91cee3d09cbef04;p=gnulib.git

diff --git a/lib/putenv.c b/lib/putenv.c
index 58a498fda..1c097ccc4 100644
--- a/lib/putenv.c
+++ b/lib/putenv.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 1994, 1997, 1998, 2000 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 1994, 1997, 1998, 2000, 2003, 2004 Free Software Foundation, Inc.
 
    NOTE: The canonical source of this file is maintained with the GNU C
    Library.  Bugs can be reported to bug-glibc@prep.ai.mit.edu.
@@ -21,45 +21,84 @@
 # include <config.h>
 #endif
 
-#include <sys/types.h>
+#include <stddef.h>
 
 /* Include errno.h *after* sys/types.h to work around header problems
    on AIX 3.2.5.  */
 #include <errno.h>
+#ifndef __set_errno
+# define __set_errno(ev) ((errno) = (ev))
+#endif
 
-/* Don't include stdlib.h because some (e.g., Solaris 2.7) declare putenv
+/* Don't include stdlib.h because some (e.g., Solaris 7) declare putenv
    with a non-const argument.  That would conflict with the declaration of
    rpl_putenv below (due to the #define putenv rpl_putenv from config.h).  */
 
-char *malloc ();
+void *malloc ();
 void free ();
 
-#if defined (__GNU_LIBRARY__) || defined (HAVE_STRING_H)
-# include <string.h>
-#endif
+#include <string.h>
+
 #if defined (__GNU_LIBRARY__) || defined (HAVE_UNISTD_H)
 # include <unistd.h>
 #endif
 
-#if !defined (__GNU_LIBRARY__) && !defined (HAVE_STRCHR)
-# define strchr index
-#endif
-#if !defined (__GNU_LIBRARY__) && !defined (HAVE_MEMCPY)
-# define memcpy(d,s,n) bcopy ((s), (d), (n))
-#endif
-
 #if HAVE_GNU_LD
 # define environ __environ
 #else
 extern char **environ;
 #endif
 
-#ifndef NULL
-# define NULL 0
+#if _LIBC
+/* This lock protects against simultaneous modifications of `environ'.  */
+# include <bits/libc-lock.h>
+__libc_lock_define_initialized (static, envlock)
+# define LOCK	__libc_lock_lock (envlock)
+# define UNLOCK	__libc_lock_unlock (envlock)
+#else
+# define LOCK
+# define UNLOCK
 #endif
 
+static int
+unsetenv (const char *name)
+{
+  size_t len;
+  char **ep;
+
+  if (name == NULL || *name == '\0' || strchr (name, '=') != NULL)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  len = strlen (name);
+
+  LOCK;
+
+  ep = environ;
+  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;
+
+  UNLOCK;
+
+  return 0;
+}
+
 
-/* Put STRING, which is of the form "NAME=VALUE", in the environment.  */
+/* Put STRING, which is of the form "NAME=VALUE", in the environment.
+   If STRING contains no `=', then remove STRING from the environment.  */
 int
 rpl_putenv (const char *string)
 {
@@ -70,18 +109,7 @@ rpl_putenv (const char *string)
   if (name_end == NULL)
     {
       /* Remove the variable from the environment.  */
-      size = strlen (string);
-      for (ep = environ; *ep != NULL; ++ep)
-	if (!strncmp (*ep, string, size) && (*ep)[size] == '=')
-	  {
-	    while (ep[1] != NULL)
-	      {
-		ep[0] = ep[1];
-		++ep;
-	      }
-	    *ep = NULL;
-	    return 0;
-	  }
+      return unsetenv (string);
     }
 
   size = 0;
@@ -103,7 +131,7 @@ rpl_putenv (const char *string)
       new_environ[size] = (char *) string;
       new_environ[size + 1] = NULL;
       if (last_environ != NULL)
-	free ((void *) last_environ);
+	free (last_environ);
       last_environ = new_environ;
       environ = new_environ;
     }