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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
commite1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe (patch)
treef5cc731bedcac0fb7fe14d952e4581e749f8bb87 /lib/unsetenv.c
parentInitial commit. (diff)
downloadcoreutils-upstream.tar.xz
coreutils-upstream.zip
Adding upstream version 9.4.upstream/9.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/unsetenv.c')
-rw-r--r--lib/unsetenv.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/lib/unsetenv.c b/lib/unsetenv.c
new file mode 100644
index 0000000..e548949
--- /dev/null
+++ b/lib/unsetenv.c
@@ -0,0 +1,127 @@
+/* Copyright (C) 1992, 1995-2002, 2005-2023 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ This file 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.
+
+ This file 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 Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Don't use __attribute__ __nonnull__ in this compilation unit. Otherwise gcc
+ optimizes away the name == NULL test below. */
+#define _GL_ARG_NONNULL(params)
+
+#include <config.h>
+
+/* Specification. */
+#include <stdlib.h>
+
+#include <errno.h>
+#if !_LIBC
+# define __set_errno(ev) ((errno) = (ev))
+#endif
+
+#include <string.h>
+#include <unistd.h>
+
+#if !_LIBC
+# define __environ environ
+#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
+
+#if _LIBC || !HAVE_UNSETENV
+
+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
+
+#else /* HAVE_UNSETENV */
+
+# undef unsetenv
+# if !HAVE_DECL_UNSETENV
+# if VOID_UNSETENV
+extern void unsetenv (const char *);
+# else
+extern int unsetenv (const char *);
+# endif
+# endif
+
+/* Call the underlying unsetenv, in case there is hidden bookkeeping
+ that needs updating beyond just modifying environ. */
+int
+rpl_unsetenv (const char *name)
+{
+ int result = 0;
+ if (!name || !*name || strchr (name, '='))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ while (getenv (name))
+# if !VOID_UNSETENV
+ result =
+# endif
+ unsetenv (name);
+ return result;
+}
+
+#endif /* HAVE_UNSETENV */