2.5-18.1

elf/dl-environ.c

@@ -0,0 +1,86 @@
+/* Environment handling for dynamic loader.
+   Copyright (C) 1995-1998, 2000, 2001, 2002 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+
+/* Walk through the environment of the process and return all entries
+   starting with `LD_'.  */
+char *
+internal_function
+_dl_next_ld_env_entry (char ***position)
+{
+  char **current = *position;
+  char *result = NULL;
+
+  while (*current != NULL)
+    {
+      if (__builtin_expect ((*current)[0] == 'L', 0)
+	  && (*current)[1] == 'D' && (*current)[2] == '_')
+	{
+	  result = &(*current)[3];
+
+	  /* Save current position for next visit.  */
+	  *position = ++current;
+
+	  break;
+	}
+
+      ++current;
+    }
+
+  return result;
+}
+
+
+/* In ld.so __environ is not exported.  */
+extern char **__environ attribute_hidden;
+
+int
+unsetenv (const char *name)
+{
+  char **ep;
+
+  ep = __environ;
+  while (*ep != NULL)
+    {
+      size_t cnt = 0;
+
+      while ((*ep)[cnt] == name[cnt] && name[cnt] != '\0')
+	++cnt;
+
+      if (name[cnt] == '\0' && (*ep)[cnt] == '=')
+	{
+	  /* Found it.  Remove this pointer by moving later ones to
+	     the front.  */
+	  char **dp = ep;
+
+	  do
+	    dp[0] = dp[1];
+	  while (*dp++);
+	  /* Continue the loop in case NAME appears again.  */
+	}
+      else
+	++ep;
+    }
+
+  return 0;
+}