use generic rotate_left & rotate_right functions

diff --git a/source/rb/rb.c b/source/rb/rb.c
index 3eaaaf32c07e94dcb93aac3c3777532e7ffb8512..c0c69e41d343a48014e50e63f4be9a36f6558c12 100644 (file)
--- a/source/rb/rb.c
+++ b/source/rb/rb.c
@@ -38,9 +38,47 @@ static rb_color_t node_color(rb_node_t* node){
        return (node ? node->color : BLACK);
 }
 
+static void rotate_right(rb_tree_t* tree, rb_node_t* node){
+       rb_node_t* edon = node->left;
+       if(edon) {
+               //attach edon in node's place:
+               if(node->parent == NULL) tree->root = edon;
+               else if(node->parent->left == node) node->parent->left = edon;
+               else node->parent->right = edon;
+               edon->parent = node->parent;
+               //reattach edon's right to node's left
+               //safe to overwrite node->left : is edon
+               node->left = edon->right;
+               if(edon->right) edon->right->parent = node;
+               //attach node to edon
+               edon->right = node;
+               node->parent = edon;
+       } /* else something went wrong... */
+}
+
+static void rotate_left(rb_tree_t* tree, rb_node_t* node){
+       rb_node_t* edon = node->right;
+       if(edon) {
+               //attach edon in node's place:
+               if(node->parent == NULL) tree->root = edon;
+               else if(node->parent->left == node) node->parent->left = edon;
+               else node->parent->right = edon;
+               edon->parent = node->parent;
+               //reattach edon's left to node's right
+               //safe to overwrite node->right : is edon
+               node->right = edon->left;
+               if(edon->left) edon->left->parent = node;
+               //attach node to edon
+               edon->left = node;
+               node->parent = edon;
+       } /* else something went wrong... */
+}
+
 static void rb_tree_rotate_outside_left(rb_tree_t* tree, rb_node_t* node){
        rb_node_t* parent = node->parent;
        rb_node_t* grandparent = (parent ? parent->parent : NULL);
+       rotate_right(tree, grandparent);
+       /*
        //rb_node_t* uncle = (grandparent ? (parent == grandparent->left ? grandparent->right : grandparent->left) : NULL);
        rb_node_t* greatgrand = (grandparent ? grandparent->parent : NULL);
        //move parent to grandparent's position:
@@ -56,6 +94,7 @@ static void rb_tree_rotate_outside_left(rb_tree_t* tree, rb_node_t* node){
        //repair the tree root
        if(tree->root == grandparent) tree->root = parent;
        //repaint nodes as needed:
+       */
        parent->color = BLACK;
        grandparent->color = RED;
 }
@@ -64,6 +103,8 @@ static void rb_tree_rotate_outside_left(rb_tree_t* tree, rb_node_t* node){
 static void rb_tree_rotate_outside_right(rb_tree_t* tree, rb_node_t* node){
        rb_node_t* parent = node->parent;
        rb_node_t* grandparent = (parent ? parent->parent : NULL);
+       rotate_left(tree, grandparent);
+       /*
        //rb_node_t* uncle = (grandparent ? (parent == grandparent->left ? grandparent->right : grandparent->left) : NULL);
        rb_node_t* greatgrand = (grandparent ? grandparent->parent : NULL);
        //move parent to grandparent's position
@@ -77,6 +118,7 @@ static void rb_tree_rotate_outside_right(rb_tree_t* tree, rb_node_t* node){
        //repair the tree root
        if(tree->root == grandparent) tree->root = parent;
        //repaint nodes
+       */
        parent->color = BLACK;
        grandparent->color = RED;
 }
@@ -99,21 +141,27 @@ static void rb_tree_ins_recolor(rb_tree_t* tree, rb_node_t* node){
        }else if(node == parent->right && parent == grandparent->left){
                //parent is red, uncle is black, "inside left" case
                //first rotate node and parent
+               rotate_left(tree, parent);
+               /*
                grandparent->left = node;
                node->parent = grandparent;
                node->left = parent;
                parent->parent = node;
                parent->right = NULL;
+               */
                //tree now transformed to an "outside left" case
                rb_tree_rotate_outside_left(tree, parent);
        }else if(node == parent->left && parent == grandparent->right){
                //parent is red, uncle is black, "inside right" case
                //first rotate node and parent
+               rotate_right(tree, parent);
+               /*
                grandparent->right = node;
                node->parent = grandparent;
                node->right = parent;
                parent->parent = node;
                parent->left = NULL;
+               */
                //tree now transformed to an "outside right" case
                rb_tree_rotate_outside_right(tree, parent);
        }else if(node == parent->left && parent == grandparent->left){