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author | Ludovic Courtès <ludo@gnu.org> | 2009-08-17 23:39:56 +0200 |
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committer | Ludovic Courtès <ludo@gnu.org> | 2009-08-18 00:06:45 +0200 |
commit | fbb857a472eb4e69c1cba05e86646b7004f32df6 (patch) | |
tree | ff23e64de5a558b575ed812349d8af6e64d8ceb4 /lib/putenv.c | |
parent | 49c9839eae84f7f3cd10db45f389fa1ea1050659 (diff) | |
parent | e33a910dd0f430f34c32fe6846899aee33fc2cf6 (diff) | |
download | guile-fbb857a472eb4e69c1cba05e86646b7004f32df6.tar.gz |
Merge branch 'master' into boehm-demers-weiser-gc
Conflicts:
lib/Makefile.am
libguile/Makefile.am
libguile/frames.c
libguile/gc-card.c
libguile/gc-freelist.c
libguile/gc-mark.c
libguile/gc-segment.c
libguile/gc_os_dep.c
libguile/load.c
libguile/macros.c
libguile/objcodes.c
libguile/programs.c
libguile/strings.c
libguile/vm.c
m4/gnulib-cache.m4
m4/gnulib-comp.m4
m4/inline.m4
Diffstat (limited to 'lib/putenv.c')
-rw-r--r-- | lib/putenv.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/lib/putenv.c b/lib/putenv.c new file mode 100644 index 000000000..53cc83912 --- /dev/null +++ b/lib/putenv.c @@ -0,0 +1,132 @@ +/* Copyright (C) 1991, 1994, 1997-1998, 2000, 2003-2008 + 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. + + This program 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 3 of the License, or 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 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 <http://www.gnu.org/licenses/>. */ + +#include <config.h> + +/* Specification. */ +#include <stdlib.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 + +#include <string.h> +#include <unistd.h> + +#if HAVE_GNU_LD +# define environ __environ +#else +extern char **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 + +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. + If STRING contains no `=', then remove STRING from the environment. */ +int +putenv (char *string) +{ + const char *const name_end = strchr (string, '='); + register size_t size; + register char **ep; + + if (name_end == NULL) + { + /* Remove the variable from the environment. */ + return _unsetenv (string); + } + + size = 0; + for (ep = environ; *ep != NULL; ++ep) + if (!strncmp (*ep, string, name_end - string) && + (*ep)[name_end - string] == '=') + break; + else + ++size; + + if (*ep == NULL) + { + static char **last_environ = NULL; + char **new_environ = (char **) malloc ((size + 2) * sizeof (char *)); + if (new_environ == NULL) + return -1; + (void) memcpy ((void *) new_environ, (void *) environ, + size * sizeof (char *)); + new_environ[size] = (char *) string; + new_environ[size + 1] = NULL; + free (last_environ); + last_environ = new_environ; + environ = new_environ; + } + else + *ep = string; + + return 0; +} |