diff options
Diffstat (limited to 'tests/unsetenv.c')
-rw-r--r-- | tests/unsetenv.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/tests/unsetenv.c b/tests/unsetenv.c new file mode 100644 index 0000000..73ea878 --- /dev/null +++ b/tests/unsetenv.c @@ -0,0 +1,90 @@ +/* Copyright (C) 1992,1995-1999,2000-2002,2005-2008 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */ + +#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 + + +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 |