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authorAnas Nashif <anas.nashif@intel.com>2012-07-21 17:12:39 +0100
committerAnas Nashif <anas.nashif@intel.com>2012-07-23 10:19:53 +0100
commit3f1932e927ae070261a8d428d5c5f158c2f525ba (patch)
tree286e9acc48a43dd751e4112144eb7d4d6ba62533 /lib/unsetenv.c
parentf86053dd05b02441d0c27eb68524ae3c1cf0fe81 (diff)
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downgrade to 2.8 (GPLv2)
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Diffstat (limited to 'lib/unsetenv.c')
-rw-r--r--lib/unsetenv.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/lib/unsetenv.c b/lib/unsetenv.c
new file mode 100644
index 0000000..0f83744
--- /dev/null
+++ b/lib/unsetenv.c
@@ -0,0 +1,92 @@
+/* Copyright (C) 1992,1995-1999,2000-2002,2005-2006 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#include <config.h>
+
+#include <errno.h>
+#if !_LIBC
+# define __set_errno(ev) ((errno) = (ev))
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#if !_LIBC
+# define __environ environ
+# ifndef HAVE_ENVIRON_DECL
+extern char **environ;
+# endif
+#endif
+
+#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
+
+/* In the GNU C library we must keep the namespace clean. */
+#ifdef _LIBC
+# define unsetenv __unsetenv
+#endif
+
+
+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;
+}
+
+#ifdef _LIBC
+# undef unsetenv
+weak_alias (__unsetenv, unsetenv)
+#endif