2000-10-06 Dave Brolley <brolley@redhat.com>

[deliverable/binutils-gdb.git] / libiberty / splay-tree.c

diff --git a/libiberty/splay-tree.c b/libiberty/splay-tree.c
index 22ea07d84adb5eada30579685da96e21d99f6841..609cd68031808a230aff643c631ca487ecf12033 100644 (file)
--- a/libiberty/splay-tree.c
+++ b/libiberty/splay-tree.c
@@ -32,6 +32,8 @@ Boston, MA 02111-1307, USA.  */
 #include <stdlib.h>
 #endif
 
+#include <stdio.h>
+
 #include "libiberty.h"
 #include "splay-tree.h"
 
@@ -309,6 +311,47 @@ splay_tree_insert (sp, key, value)
   return sp->root;
 }
 
+/* Remove KEY from SP.  It is not an error if it did not exist.  */
+
+void
+splay_tree_remove (sp, key)
+     splay_tree sp;
+     splay_tree_key key;
+{
+  splay_tree_splay (sp, key);
+
+  if (sp->root && (*sp->comp) (sp->root->key, key) == 0)
+    {
+      splay_tree_node left, right;
+
+      left = sp->root->left;
+      right = sp->root->right;
+
+      /* Delete the root node itself.  */
+      if (sp->delete_value)
+       (*sp->delete_value) (sp->root->value);
+      free (sp->root);
+
+      /* One of the children is now the root.  Doesn't matter much
+        which, so long as we preserve the properties of the tree.  */
+      if (left)
+       {
+         sp->root = left;
+
+         /* If there was a right child as well, hang it off the 
+            right-most leaf of the left child.  */
+         if (right)
+           {
+             while (left->right)
+               left = left->right;
+             left->right = right;
+           }
+       }
+      else
+       sp->root = right;
+    }
+}
+
 /* Lookup KEY in SP, returning VALUE if present, and NULL 
    otherwise.  */