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-rw-r--r--libguile/putenv.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/libguile/putenv.c b/libguile/putenv.c
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+++ b/libguile/putenv.c
@@ -0,0 +1,111 @@
+/* Copyright (C) 1991 Free Software Foundation, Inc.
+
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#ifdef HAVE_CONFIG_H
+#include "libguile/scmconfig.h"
+#endif
+
+#include <sys/types.h>
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+
+/* Don't include stdlib.h for non-GNU C libraries because some of them
+ contain conflicting prototypes for getopt.
+ This needs to come after some library #include
+ to get __GNU_LIBRARY__ defined. */
+#ifdef __GNU_LIBRARY__
+#include <stdlib.h>
+#else
+char *malloc ();
+#endif /* GNU C library. */
+
+#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
+#include <string.h>
+#else
+#include <strings.h>
+#ifndef strchr
+#define strchr index
+#endif
+#ifndef memcpy
+#define memcpy(d, s, n) bcopy((s), (d), (n))
+#endif
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifndef NULL
+#define NULL 0
+#endif
+
+extern char **environ;
+
+/* Put STRING, which is of the form "NAME=VALUE", in the environment. */
+int
+putenv (string)
+ const char *string;
+{
+ char *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;
+ memcpy ((char *) new_environ, (char *) environ, size * sizeof (char *));
+ new_environ[size] = (char *) string;
+ new_environ[size + 1] = NULL;
+ if (last_environ != NULL)
+ free ((char *) last_environ);
+ last_environ = new_environ;
+ environ = new_environ;
+ }
+ else
+ *ep = (char *) string;
+
+ return 0;
+}