1 files changed, 97 insertions, 0 deletions
diff --git a/libc/misc/setenv.c b/libc/misc/setenv.c
new file mode 100644
index 0000000..10b32d2
--- /dev/null
+++ b/libc/misc/setenv.c
@@ -0,0 +1,97 @@
+/* Copyright (C) 1992, 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.  */
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+extern char ** environ;
+
+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);
+  int result = 0;
+
+  size = 0;
+  for (ep = environ; *ep != NULL; ++ep)
+    if (!memcmp (*ep, name, namelen) && (*ep)[namelen] == '=')
+      break;
+    else
+      ++size;
+  
+  if (*ep == NULL)
+    {
+      static char **last_environ = NULL;
+      char **new_environ = (char **) malloc((size + 2) * sizeof(char *));
+      if (new_environ == NULL)
+	{
+	  result = -1;
+	  goto do_return;
+	}
+      (void) memcpy((void*) new_environ, (void*) environ, size * sizeof(char *));
+
+      new_environ[size] = malloc (namelen + 1 + vallen + 1);
+      if (new_environ[size] == NULL)
+	{
+	  free (new_environ);
+	  errno = ENOMEM;
+	  result = -1;
+	  goto do_return;
+	}
+      memcpy (new_environ[size], name, namelen);
+      new_environ[size][namelen] = '=';
+      memcpy (&new_environ[size][namelen + 1], value, vallen + 1);
+
+      new_environ[size + 1] = NULL;
+
+      if (last_environ != NULL)
+	free ((void*) last_environ);
+      last_environ = new_environ;
+      environ = new_environ;
+    }
+  else if (replace)
+    {
+      size_t len = strlen (*ep);
+      if (len < namelen + 1 + vallen)
+	{
+	  char *new = malloc (namelen + 1 + vallen + 1);
+	  if (new == NULL)
+	    {
+	      result = -1;
+	      goto do_return;
+	    }
+	  *ep = new;
+	}
+      memcpy (*ep, name, namelen);
+      (*ep)[namelen] = '=';
+      memcpy (&(*ep)[namelen + 1], value, vallen + 1);
+    }
+
+do_return:
+  return result;
+}
+
+void
+unsetenv(name)
+__const char *name;
+{
+  register char **ep;
+  register char **dp;
+  __const size_t namelen = strlen (name);
+
+  for (dp = ep = environ; *ep != NULL; ++ep)
+    if (memcmp (*ep, name, namelen) || (*ep)[namelen] != '=')
+      {
+	*dp = *ep;
+	++dp;
+      }
+  *dp = NULL;
+}