/* Copyright (C) 1991, 1994, 1997, 1998, 2000, 2003, 2004, 2005, 2006, 2007 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 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 /* undef putenv here, because some (e.g., Solaris 10) declare putenv in 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). */ #undef putenv int rpl_putenv (char const *); #include /* Include errno.h *after* sys/types.h to work around header problems on AIX 3.2.5. */ #include #ifndef __set_errno # define __set_errno(ev) ((errno) = (ev)) #endif #include #include #include #if HAVE_GNU_LD # define environ __environ #else extern char **environ; #endif #if _LIBC /* This lock protects against simultaneous modifications of `environ'. */ # include __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 rpl_putenv (const 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; if (last_environ != NULL) free (last_environ); last_environ = new_environ; environ = new_environ; } else *ep = (char *) string; return 0; }