1 files changed, 80 insertions, 0 deletions
diff --git a/lib/list_util.c b/lib/list_util.c
new file mode 100644
index 00000000..720b8ca7
--- /dev/null
+++ b/lib/list_util.c
@@ -0,0 +1,80 @@
+/* List Utilities
+ * Copyright (C) 2009 Chris Hall (GMCH), Highwayman
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra 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.
+ *
+ * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <list_util.h>
+
+
+/*==============================================================================
+ * Single Base, Single Link
+ */
+
+/*------------------------------------------------------------------------------
+ * Deleting item
+ *
+ * Have to chase down list to find item.
+ *
+ * Note that p_this:
+ *
+ *   * starts as pointer to the base pointer, so should really be void**,
+ *     but that causes all sorts of problems with strict-aliasing.
+ *
+ *     So: have to cast to (void**) before dereferencing to get the address
+ *         of the first item on the list.
+ *
+ *   * as steps along the list p_this points to the "next pointer" in the
+ *     previous item.
+ *
+ *     The _sl_p_next() macro adds the offset of the "next pointer" to the
+ *     address of the this item.
+ *
+ *   * at the end, assigns the item's "next pointer" to the "next pointer"
+ *     field pointed at by p_this.
+ *
+ *     Note again the cast to (void**).
+ *
+ * Returns: 0 => OK -- removed item from list (OR item == NULL)
+ *         -1 => item not found on list
+ */
+extern int
+ssl_del_func(void* p_this, void* item, size_t link_offset)
+{
+  void* this ;
+
+  if (item == NULL)
+    return 0 ;
+
+  while ((this = *(void**)p_this) != item)
+    {
+      if (this == NULL)
+        return -1 ;
+
+      p_this = _sl_p_next(this, link_offset) ;
+    } ;
+
+  *(void**)p_this = _sl_next(item, link_offset) ;
+
+  return 0 ;
+} ;
+
+/*==============================================================================
+ * Single Base, Double Link
+ */
+