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-rw-r--r--lib/setenv.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/lib/setenv.c b/lib/setenv.c
new file mode 100644
index 000000000..d397753d9
--- /dev/null
+++ b/lib/setenv.c
@@ -0,0 +1,128 @@
+/* Copyright (C) 1992, 1995 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+USA. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <errno.h>
+
+#if _LIBC || HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#if _LIBC || HAVE_STRING_H
+#include <string.h>
+#endif
+#if _LIBC || HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifndef HAVE_GNU_LD
+#define __environ environ
+#endif
+
+int
+setenv (name, value, replace)
+ const char *name;
+ const char *value;
+ int replace;
+{
+ register char **ep;
+ register size_t size;
+ const size_t namelen = strlen (name);
+ const size_t vallen = strlen (value) + 1;
+
+ size = 0;
+ for (ep = __environ; *ep != NULL; ++ep)
+ if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
+ break;
+ else
+ ++size;
+
+ if (*ep == NULL)
+ {
+ static char **last_environ;
+ char **new_environ;
+ if (__environ == last_environ)
+ /* We allocated this space; we can extend it. */
+ new_environ = (char **) realloc (last_environ,
+ (size + 2) * sizeof (char *));
+ else
+ new_environ = (char **) malloc ((size + 2) * sizeof (char *));
+
+ if (new_environ == NULL)
+ return -1;
+
+ new_environ[size] = malloc (namelen + 1 + vallen);
+ if (new_environ[size] == NULL)
+ {
+ free ((char *) new_environ);
+ errno = ENOMEM;
+ return -1;
+ }
+
+ if (__environ != last_environ)
+ memcpy ((char *) new_environ, (char *) __environ,
+ size * sizeof (char *));
+
+ memcpy (new_environ[size], name, namelen);
+ new_environ[size][namelen] = '=';
+ memcpy (&new_environ[size][namelen + 1], value, vallen);
+
+ new_environ[size + 1] = NULL;
+
+ last_environ = __environ = new_environ;
+ }
+ else if (replace)
+ {
+ size_t len = strlen (*ep);
+ if (len + 1 < namelen + 1 + vallen)
+ {
+ /* The existing string is too short; malloc a new one. */
+ char *new = malloc (namelen + 1 + vallen);
+ if (new == NULL)
+ return -1;
+ *ep = new;
+ }
+ memcpy (*ep, name, namelen);
+ (*ep)[namelen] = '=';
+ memcpy (&(*ep)[namelen + 1], value, vallen);
+ }
+
+ return 0;
+}
+
+void
+unsetenv (const char *name)
+{
+ const size_t len = strlen (name);
+ char **ep;
+
+ for (ep = __environ; *ep; ++ep)
+ 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. */
+ }
+}