diff options
Diffstat (limited to 'sysdeps/generic/putenv.c')
-rw-r--r-- | sysdeps/generic/putenv.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/sysdeps/generic/putenv.c b/sysdeps/generic/putenv.c new file mode 100644 index 0000000..77a8393 --- /dev/null +++ b/sysdeps/generic/putenv.c @@ -0,0 +1,101 @@ +/* Copyright (C) 1991, 1994 Free Software Foundation, Inc. + +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <errno.h> + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#if defined (__GNU_LIBRARY__) || defined (HAVE_STDLIB_H) +#include <stdlib.h> +#endif +#if defined (__GNU_LIBRARY__) || defined (HAVE_STRING_H) +#include <string.h> +#endif +#if defined (__GNU_LIBRARY__) || defined (HAVE_UNISTD_H) +#include <unistd.h> +#endif + +#if !defined (__GNU_LIBRARY__) && !defined (HAVE_STRCHR) +#define strchr index +#endif +#if !defined (__GNU_LIBRARY__) && !defined (HAVE_MEMCPY) +#define memcpy(d,s,n) bcopy ((s), (d), (n)) +#endif + +#ifndef HAVE_GNU_LD +#define __environ environ +#endif + + +/* Put STRING, which is of the form "NAME=VALUE", in the environment. */ +int +putenv (string) + 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. */ + size = strlen (string); + for (ep = __environ; *ep != NULL; ++ep) + if (!strncmp (*ep, string, size) && (*ep)[size] == '=') + { + while (ep[1] != NULL) + { + ep[0] = ep[1]; + ++ep; + } + *ep = NULL; + return 0; + } + } + + 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 ((void *) last_environ); + last_environ = new_environ; + __environ = new_environ; + } + else + *ep = (char *) string; + + return 0; +} |