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1410.4.2
by Djellel E. Difallah
removing my |
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/* Copyright (C) 2000 MySQL AB
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
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/*
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Code for handling red-black (balanced) binary trees.
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key in tree is allocated accrding to following:
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1) If size < 0 then tree will not allocate keys and only a pointer to
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each key is saved in tree.
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compare and search functions uses and returns key-pointer
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2) If size == 0 then there are two options:
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- key_size != 0 to tree_insert: The key will be stored in the tree.
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- key_size == 0 to tree_insert: A pointer to the key is stored.
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compare and search functions uses and returns key-pointer.
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3) if key_size is given to init_tree then each node will continue the
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key and calls to insert_key may increase length of key.
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if key_size > sizeof(pointer) and key_size is a multiple of 8 (double
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allign) then key will be put on a 8 alligned adress. Else
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the key will be on adress (element+1). This is transparent for user
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compare and search functions uses a pointer to given key-argument.
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- If you use a free function for tree-elements and you are freeing
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the element itself, you should use key_size = 0 to init_tree and
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tree_search
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The actual key in TREE_ELEMENT is saved as a pointer or after the
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TREE_ELEMENT struct.
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If one uses only pointers in tree one can use tree_set_pointer() to
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change address of data.
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Implemented by monty.
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*/
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/*
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NOTE:
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tree->compare function should be ALWAYS called as
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(*tree->compare)(custom_arg, ELEMENT_KEY(tree,element), key)
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and not other way around, as
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(*tree->compare)(custom_arg, key, ELEMENT_KEY(tree,element))
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*/
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#include "config.h" |
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#include "drizzled/tree.h" |
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#include "drizzled/internal/my_sys.h" |
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#include "drizzled/internal/m_string.h" |
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#include "drizzled/memory/root.h" |
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#define BLACK 1
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#define RED 0
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#define DEFAULT_ALLOC_SIZE 8192
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#define DEFAULT_ALIGN_SIZE 8192
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#define ELEMENT_KEY(tree,element)\
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(tree->offset_to_key ? (void*)((unsigned char*) element+tree->offset_to_key) :\
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*((void**) (element+1)))
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#define ELEMENT_CHILD(element, offs) (*(TREE_ELEMENT**)((char*)element + offs))
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namespace drizzled |
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{
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static void delete_tree_element(TREE *,TREE_ELEMENT *); |
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static int tree_walk_left_root_right(TREE *,TREE_ELEMENT *, |
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tree_walk_action,void *); |
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static int tree_walk_right_root_left(TREE *,TREE_ELEMENT *, |
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tree_walk_action,void *); |
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static void left_rotate(TREE_ELEMENT **parent,TREE_ELEMENT *leaf); |
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static void right_rotate(TREE_ELEMENT **parent, TREE_ELEMENT *leaf); |
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static void rb_insert(TREE *tree,TREE_ELEMENT ***parent, |
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TREE_ELEMENT *leaf); |
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static void rb_delete_fixup(TREE *tree,TREE_ELEMENT ***parent); |
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void init_tree(TREE *tree, size_t default_alloc_size, uint32_t memory_limit, |
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uint32_t size, qsort_cmp2 compare, bool with_delete, |
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tree_element_free free_element, void *custom_arg) |
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{
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if (default_alloc_size < DEFAULT_ALLOC_SIZE) |
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default_alloc_size= DEFAULT_ALLOC_SIZE; |
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default_alloc_size= MY_ALIGN(default_alloc_size, DEFAULT_ALIGN_SIZE); |
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memset(&tree->null_element, 0, sizeof(tree->null_element)); |
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tree->root= &tree->null_element; |
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tree->compare= compare; |
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tree->size_of_element= size > 0 ? (uint32_t) size : 0; |
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tree->memory_limit= memory_limit; |
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tree->free= free_element; |
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tree->allocated= 0; |
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tree->elements_in_tree= 0; |
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tree->custom_arg = custom_arg; |
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tree->null_element.colour= BLACK; |
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tree->null_element.left=tree->null_element.right= 0; |
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tree->flag= 0; |
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if (!free_element && |
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(size <= sizeof(void*) || ((uint32_t) size & (sizeof(void*)-1)))) |
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{
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/*
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We know that the data doesn't have to be aligned (like if the key
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contains a double), so we can store the data combined with the
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TREE_ELEMENT.
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*/
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tree->offset_to_key= sizeof(TREE_ELEMENT); /* Put key after element */ |
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/* Fix allocation size so that we don't lose any memory */
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default_alloc_size/= (sizeof(TREE_ELEMENT)+size); |
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if (!default_alloc_size) |
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default_alloc_size= 1; |
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default_alloc_size*= (sizeof(TREE_ELEMENT)+size); |
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}
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else
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{
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tree->offset_to_key= 0; /* use key through pointer */ |
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tree->size_of_element+= sizeof(void*); |
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}
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if (! (tree->with_delete= with_delete)) |
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{
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1487
by Brian Aker
More updates for memory::Root |
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tree->mem_root.init_alloc_root(default_alloc_size); |
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1410.4.2
by Djellel E. Difallah
removing my |
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tree->mem_root.min_malloc= (sizeof(TREE_ELEMENT)+tree->size_of_element); |
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}
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}
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static void free_tree(TREE *tree, myf free_flags) |
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{
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if (tree->root) /* If initialized */ |
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{
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if (tree->with_delete) |
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delete_tree_element(tree,tree->root); |
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else
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{
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if (tree->free) |
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{
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if (tree->memory_limit) |
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(*tree->free)(NULL, free_init, tree->custom_arg); |
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delete_tree_element(tree,tree->root); |
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if (tree->memory_limit) |
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(*tree->free)(NULL, free_end, tree->custom_arg); |
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}
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1487
by Brian Aker
More updates for memory::Root |
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tree->mem_root.free_root(free_flags); |
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1410.4.2
by Djellel E. Difallah
removing my |
152 |
}
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}
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tree->root= &tree->null_element; |
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tree->elements_in_tree= 0; |
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tree->allocated= 0; |
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}
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void delete_tree(TREE* tree) |
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{
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free_tree(tree, MYF(0)); /* free() mem_root if applicable */ |
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}
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void reset_tree(TREE* tree) |
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{
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/* do not free mem_root, just mark blocks as free */
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free_tree(tree, MYF(memory::MARK_BLOCKS_FREE)); |
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}
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static void delete_tree_element(TREE *tree, TREE_ELEMENT *element) |
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{
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if (element != &tree->null_element) |
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{
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delete_tree_element(tree,element->left); |
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if (tree->free) |
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(*tree->free)(ELEMENT_KEY(tree,element), free_free, tree->custom_arg); |
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delete_tree_element(tree,element->right); |
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if (tree->with_delete) |
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free((char*) element); |
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}
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}
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/*
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insert, search and delete of elements
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The following should be true:
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parent[0] = & parent[-1][0]->left ||
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parent[0] = & parent[-1][0]->right
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*/
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TREE_ELEMENT *tree_insert(TREE *tree, void *key, uint32_t key_size, |
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void* custom_arg) |
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{
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int cmp; |
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TREE_ELEMENT *element,***parent; |
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parent= tree->parents; |
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*parent = &tree->root; element= tree->root; |
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for (;;) |
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{
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if (element == &tree->null_element || |
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(cmp = (*tree->compare)(custom_arg, ELEMENT_KEY(tree,element), |
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key)) == 0) |
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break; |
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if (cmp < 0) |
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{
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*++parent= &element->right; element= element->right; |
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}
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else
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{
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*++parent = &element->left; element= element->left; |
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}
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}
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if (element == &tree->null_element) |
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{
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size_t alloc_size= sizeof(TREE_ELEMENT)+key_size+tree->size_of_element; |
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tree->allocated+= alloc_size; |
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if (tree->memory_limit && tree->elements_in_tree |
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&& tree->allocated > tree->memory_limit) |
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{
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reset_tree(tree); |
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return tree_insert(tree, key, key_size, custom_arg); |
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}
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key_size+= tree->size_of_element; |
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if (tree->with_delete) |
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element= (TREE_ELEMENT *) malloc(alloc_size); |
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else
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1485
by Brian Aker
Updates to confine memroot |
232 |
element= (TREE_ELEMENT *) tree->mem_root.alloc_root(alloc_size); |
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1410.4.2
by Djellel E. Difallah
removing my |
233 |
if (!element) |
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return(NULL); |
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**parent= element; |
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element->left= element->right= &tree->null_element; |
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if (!tree->offset_to_key) |
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{
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if (key_size == sizeof(void*)) /* no length, save pointer */ |
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*((void**) (element+1))= key; |
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else
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{
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*((void**) (element+1))= (void*) ((void **) (element+1)+1); |
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memcpy(*((void **) (element+1)),key, key_size - sizeof(void*)); |
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}
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}
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else
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memcpy((unsigned char*) element + tree->offset_to_key, key, key_size); |
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element->count= 1; /* May give warning in purify */ |
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tree->elements_in_tree++; |
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rb_insert(tree,parent,element); /* rebalance tree */ |
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}
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else
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{
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if (tree->flag & TREE_NO_DUPS) |
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return(NULL); |
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element->count++; |
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/* Avoid a wrap over of the count. */
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if (! element->count) |
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element->count--; |
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}
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return element; |
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}
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int tree_delete(TREE *tree, void *key, uint32_t key_size, void *custom_arg) |
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{
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int remove_colour; |
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TREE_ELEMENT *element,***parent, ***org_parent, *nod; |
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if (!tree->with_delete) |
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return 1; /* not allowed */ |
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parent= tree->parents; |
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*parent= &tree->root; element= tree->root; |
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for (;;) |
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{
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int cmp; |
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if (element == &tree->null_element) |
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return 1; /* Was not in tree */ |
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if ((cmp = (*tree->compare)(custom_arg, ELEMENT_KEY(tree,element), |
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key)) == 0) |
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break; |
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if (cmp < 0) |
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{
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*++parent= &element->right; element= element->right; |
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}
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else
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{
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*++parent = &element->left; element= element->left; |
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}
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}
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if (element->left == &tree->null_element) |
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{
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(**parent)= element->right; |
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remove_colour= element->colour; |
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}
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else if (element->right == &tree->null_element) |
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{
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(**parent)= element->left; |
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remove_colour= element->colour; |
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}
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else
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{
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org_parent= parent; |
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*++parent= &element->right; nod= element->right; |
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while (nod->left != &tree->null_element) |
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{
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*++parent= &nod->left; nod= nod->left; |
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}
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(**parent)= nod->right; /* unlink nod from tree */ |
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remove_colour= nod->colour; |
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org_parent[0][0]= nod; /* put y in place of element */ |
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org_parent[1]= &nod->right; |
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nod->left= element->left; |
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nod->right= element->right; |
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nod->colour= element->colour; |
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}
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if (remove_colour == BLACK) |
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rb_delete_fixup(tree,parent); |
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if (tree->free) |
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(*tree->free)(ELEMENT_KEY(tree,element), free_free, tree->custom_arg); |
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tree->allocated-= sizeof(TREE_ELEMENT) + tree->size_of_element + key_size; |
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free((unsigned char*) element); |
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tree->elements_in_tree--; |
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return 0; |
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328 |
}
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void *tree_search_key(TREE *tree, const void *key, |
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TREE_ELEMENT **parents, TREE_ELEMENT ***last_pos, |
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enum ha_rkey_function flag, void *custom_arg) |
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{
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TREE_ELEMENT *element= tree->root; |
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TREE_ELEMENT **last_left_step_parent= NULL, **last_right_step_parent= NULL; |
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TREE_ELEMENT **last_equal_element= NULL; |
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||
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/*
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TODO: support for HA_READ_KEY_OR_PREV, HA_READ_PREFIX flags if needed.
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*/
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341 |
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342 |
*parents = &tree->null_element; |
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while (element != &tree->null_element) |
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{
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int cmp; |
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346 |
||
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*++parents= element; |
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348 |
||
349 |
if ((cmp= (*tree->compare)(custom_arg, ELEMENT_KEY(tree, element), |
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key)) == 0) |
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{
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switch (flag) { |
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353 |
case HA_READ_KEY_EXACT: |
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354 |
case HA_READ_KEY_OR_NEXT: |
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355 |
case HA_READ_BEFORE_KEY: |
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last_equal_element= parents; |
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cmp= 1; |
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358 |
break; |
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359 |
case HA_READ_AFTER_KEY: |
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360 |
cmp= -1; |
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break; |
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362 |
case HA_READ_PREFIX_LAST: |
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363 |
case HA_READ_PREFIX_LAST_OR_PREV: |
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364 |
last_equal_element= parents; |
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365 |
cmp= -1; |
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366 |
break; |
|
367 |
default: |
|
368 |
return NULL; |
|
369 |
}
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|
370 |
}
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371 |
if (cmp < 0) /* element < key */ |
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372 |
{
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373 |
last_right_step_parent= parents; |
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374 |
element= element->right; |
|
375 |
}
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376 |
else
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|
377 |
{
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378 |
last_left_step_parent= parents; |
|
379 |
element= element->left; |
|
380 |
}
|
|
381 |
}
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|
382 |
switch (flag) { |
|
383 |
case HA_READ_KEY_EXACT: |
|
384 |
case HA_READ_PREFIX_LAST: |
|
385 |
*last_pos= last_equal_element; |
|
386 |
break; |
|
387 |
case HA_READ_KEY_OR_NEXT: |
|
388 |
*last_pos= last_equal_element ? last_equal_element : last_left_step_parent; |
|
389 |
break; |
|
390 |
case HA_READ_AFTER_KEY: |
|
391 |
*last_pos= last_left_step_parent; |
|
392 |
break; |
|
393 |
case HA_READ_PREFIX_LAST_OR_PREV: |
|
394 |
*last_pos= last_equal_element ? last_equal_element : last_right_step_parent; |
|
395 |
break; |
|
396 |
case HA_READ_BEFORE_KEY: |
|
397 |
*last_pos= last_right_step_parent; |
|
398 |
break; |
|
399 |
default: |
|
400 |
return NULL; |
|
401 |
}
|
|
402 |
||
403 |
return *last_pos ? ELEMENT_KEY(tree, **last_pos) : NULL; |
|
404 |
}
|
|
405 |
||
406 |
/*
|
|
407 |
Search first (the most left) or last (the most right) tree element
|
|
408 |
*/
|
|
409 |
void *tree_search_edge(TREE *tree, TREE_ELEMENT **parents, |
|
410 |
TREE_ELEMENT ***last_pos, int child_offs) |
|
411 |
{
|
|
412 |
TREE_ELEMENT *element= tree->root; |
|
413 |
||
414 |
*parents= &tree->null_element; |
|
415 |
while (element != &tree->null_element) |
|
416 |
{
|
|
417 |
*++parents= element; |
|
418 |
element= ELEMENT_CHILD(element, child_offs); |
|
419 |
}
|
|
420 |
*last_pos= parents; |
|
421 |
return **last_pos != &tree->null_element ? |
|
422 |
ELEMENT_KEY(tree, **last_pos) : NULL; |
|
423 |
}
|
|
424 |
||
425 |
void *tree_search_next(TREE *tree, TREE_ELEMENT ***last_pos, int l_offs, |
|
426 |
int r_offs) |
|
427 |
{
|
|
428 |
TREE_ELEMENT *x= **last_pos; |
|
429 |
||
430 |
if (ELEMENT_CHILD(x, r_offs) != &tree->null_element) |
|
431 |
{
|
|
432 |
x= ELEMENT_CHILD(x, r_offs); |
|
433 |
*++*last_pos= x; |
|
434 |
while (ELEMENT_CHILD(x, l_offs) != &tree->null_element) |
|
435 |
{
|
|
436 |
x= ELEMENT_CHILD(x, l_offs); |
|
437 |
*++*last_pos= x; |
|
438 |
}
|
|
439 |
return ELEMENT_KEY(tree, x); |
|
440 |
}
|
|
441 |
else
|
|
442 |
{
|
|
443 |
TREE_ELEMENT *y= *--*last_pos; |
|
444 |
while (y != &tree->null_element && x == ELEMENT_CHILD(y, r_offs)) |
|
445 |
{
|
|
446 |
x= y; |
|
447 |
y= *--*last_pos; |
|
448 |
}
|
|
449 |
return y == &tree->null_element ? NULL : ELEMENT_KEY(tree, y); |
|
450 |
}
|
|
451 |
}
|
|
452 |
||
453 |
/*
|
|
454 |
Expected that tree is fully balanced
|
|
455 |
(each path from root to leaf has the same length)
|
|
456 |
*/
|
|
457 |
ha_rows tree_record_pos(TREE *tree, const void *key, |
|
458 |
enum ha_rkey_function flag, void *custom_arg) |
|
459 |
{
|
|
460 |
TREE_ELEMENT *element= tree->root; |
|
461 |
double left= 1; |
|
462 |
double right= tree->elements_in_tree; |
|
463 |
||
464 |
while (element != &tree->null_element) |
|
465 |
{
|
|
466 |
int cmp; |
|
467 |
||
468 |
if ((cmp= (*tree->compare)(custom_arg, ELEMENT_KEY(tree, element), |
|
469 |
key)) == 0) |
|
470 |
{
|
|
471 |
switch (flag) { |
|
472 |
case HA_READ_KEY_EXACT: |
|
473 |
case HA_READ_BEFORE_KEY: |
|
474 |
cmp= 1; |
|
475 |
break; |
|
476 |
case HA_READ_AFTER_KEY: |
|
477 |
cmp= -1; |
|
478 |
break; |
|
479 |
default: |
|
480 |
return HA_POS_ERROR; |
|
481 |
}
|
|
482 |
}
|
|
483 |
if (cmp < 0) /* element < key */ |
|
484 |
{
|
|
485 |
element= element->right; |
|
486 |
left= (left + right) / 2; |
|
487 |
}
|
|
488 |
else
|
|
489 |
{
|
|
490 |
element= element->left; |
|
491 |
right= (left + right) / 2; |
|
492 |
}
|
|
493 |
}
|
|
494 |
||
495 |
switch (flag) { |
|
496 |
case HA_READ_KEY_EXACT: |
|
497 |
case HA_READ_BEFORE_KEY: |
|
498 |
return (ha_rows) right; |
|
499 |
case HA_READ_AFTER_KEY: |
|
500 |
return (ha_rows) left; |
|
501 |
default: |
|
502 |
return HA_POS_ERROR; |
|
503 |
}
|
|
504 |
}
|
|
505 |
||
506 |
int tree_walk(TREE *tree, tree_walk_action action, void *argument, TREE_WALK visit) |
|
507 |
{
|
|
508 |
switch (visit) { |
|
509 |
case left_root_right: |
|
510 |
return tree_walk_left_root_right(tree,tree->root,action,argument); |
|
511 |
case right_root_left: |
|
512 |
return tree_walk_right_root_left(tree,tree->root,action,argument); |
|
513 |
}
|
|
514 |
||
515 |
return 0; /* Keep gcc happy */ |
|
516 |
}
|
|
517 |
||
518 |
static int tree_walk_left_root_right(TREE *tree, TREE_ELEMENT *element, tree_walk_action action, void *argument) |
|
519 |
{
|
|
520 |
int error; |
|
521 |
if (element->left) /* Not null_element */ |
|
522 |
{
|
|
523 |
if ((error=tree_walk_left_root_right(tree,element->left,action, |
|
524 |
argument)) == 0 && |
|
525 |
(error=(*action)(ELEMENT_KEY(tree,element), |
|
526 |
element->count, |
|
527 |
argument)) == 0) |
|
528 |
error=tree_walk_left_root_right(tree,element->right,action,argument); |
|
529 |
return error; |
|
530 |
}
|
|
531 |
||
532 |
return 0; |
|
533 |
}
|
|
534 |
||
535 |
static int tree_walk_right_root_left(TREE *tree, TREE_ELEMENT *element, tree_walk_action action, void *argument) |
|
536 |
{
|
|
537 |
int error; |
|
538 |
if (element->right) /* Not null_element */ |
|
539 |
{
|
|
540 |
if ((error=tree_walk_right_root_left(tree,element->right,action, |
|
541 |
argument)) == 0 && |
|
542 |
(error=(*action)(ELEMENT_KEY(tree,element), |
|
543 |
element->count, |
|
544 |
argument)) == 0) |
|
545 |
error=tree_walk_right_root_left(tree,element->left,action,argument); |
|
546 |
return error; |
|
547 |
}
|
|
548 |
||
549 |
return 0; |
|
550 |
}
|
|
551 |
||
552 |
||
553 |
/* Functions to fix up the tree after insert and delete */
|
|
554 |
||
555 |
static void left_rotate(TREE_ELEMENT **parent, TREE_ELEMENT *leaf) |
|
556 |
{
|
|
557 |
TREE_ELEMENT *y; |
|
558 |
||
559 |
y= leaf->right; |
|
560 |
leaf->right= y->left; |
|
561 |
parent[0]= y; |
|
562 |
y->left= leaf; |
|
563 |
}
|
|
564 |
||
565 |
static void right_rotate(TREE_ELEMENT **parent, TREE_ELEMENT *leaf) |
|
566 |
{
|
|
567 |
TREE_ELEMENT *x; |
|
568 |
||
569 |
x= leaf->left; |
|
570 |
leaf->left= x->right; |
|
571 |
parent[0]= x; |
|
572 |
x->right= leaf; |
|
573 |
}
|
|
574 |
||
575 |
static void rb_insert(TREE *tree, TREE_ELEMENT ***parent, TREE_ELEMENT *leaf) |
|
576 |
{
|
|
577 |
TREE_ELEMENT *y,*par,*par2; |
|
578 |
||
579 |
leaf->colour=RED; |
|
580 |
while (leaf != tree->root && (par=parent[-1][0])->colour == RED) |
|
581 |
{
|
|
582 |
if (par == (par2=parent[-2][0])->left) |
|
583 |
{
|
|
584 |
y= par2->right; |
|
585 |
if (y->colour == RED) |
|
586 |
{
|
|
587 |
par->colour= BLACK; |
|
588 |
y->colour= BLACK; |
|
589 |
leaf= par2; |
|
590 |
parent-= 2; |
|
591 |
leaf->colour= RED; /* And the loop continues */ |
|
592 |
}
|
|
593 |
else
|
|
594 |
{
|
|
595 |
if (leaf == par->right) |
|
596 |
{
|
|
597 |
left_rotate(parent[-1],par); |
|
598 |
par= leaf; /* leaf is now parent to old leaf */ |
|
599 |
}
|
|
600 |
par->colour= BLACK; |
|
601 |
par2->colour= RED; |
|
602 |
right_rotate(parent[-2],par2); |
|
603 |
break; |
|
604 |
}
|
|
605 |
}
|
|
606 |
else
|
|
607 |
{
|
|
608 |
y= par2->left; |
|
609 |
if (y->colour == RED) |
|
610 |
{
|
|
611 |
par->colour= BLACK; |
|
612 |
y->colour= BLACK; |
|
613 |
leaf= par2; |
|
614 |
parent-= 2; |
|
615 |
leaf->colour= RED; /* And the loop continues */ |
|
616 |
}
|
|
617 |
else
|
|
618 |
{
|
|
619 |
if (leaf == par->left) |
|
620 |
{
|
|
621 |
right_rotate(parent[-1],par); |
|
622 |
par= leaf; |
|
623 |
}
|
|
624 |
par->colour= BLACK; |
|
625 |
par2->colour= RED; |
|
626 |
left_rotate(parent[-2],par2); |
|
627 |
break; |
|
628 |
}
|
|
629 |
}
|
|
630 |
}
|
|
631 |
tree->root->colour=BLACK; |
|
632 |
}
|
|
633 |
||
634 |
static void rb_delete_fixup(TREE *tree, TREE_ELEMENT ***parent) |
|
635 |
{
|
|
636 |
TREE_ELEMENT *x,*w,*par; |
|
637 |
||
638 |
x= **parent; |
|
639 |
while (x != tree->root && x->colour == BLACK) |
|
640 |
{
|
|
641 |
if (x == (par=parent[-1][0])->left) |
|
642 |
{
|
|
643 |
w= par->right; |
|
644 |
if (w->colour == RED) |
|
645 |
{
|
|
646 |
w->colour= BLACK; |
|
647 |
par->colour= RED; |
|
648 |
left_rotate(parent[-1],par); |
|
649 |
parent[0]= &w->left; |
|
650 |
*++parent= &par->left; |
|
651 |
w= par->right; |
|
652 |
}
|
|
653 |
if (w->left->colour == BLACK && w->right->colour == BLACK) |
|
654 |
{
|
|
655 |
w->colour= RED; |
|
656 |
x= par; |
|
657 |
parent--; |
|
658 |
}
|
|
659 |
else
|
|
660 |
{
|
|
661 |
if (w->right->colour == BLACK) |
|
662 |
{
|
|
663 |
w->left->colour= BLACK; |
|
664 |
w->colour= RED; |
|
665 |
right_rotate(&par->right,w); |
|
666 |
w= par->right; |
|
667 |
}
|
|
668 |
w->colour= par->colour; |
|
669 |
par->colour= BLACK; |
|
670 |
w->right->colour= BLACK; |
|
671 |
left_rotate(parent[-1],par); |
|
672 |
x= tree->root; |
|
673 |
break; |
|
674 |
}
|
|
675 |
}
|
|
676 |
else
|
|
677 |
{
|
|
678 |
w=par->left; |
|
679 |
if (w->colour == RED) |
|
680 |
{
|
|
681 |
w->colour= BLACK; |
|
682 |
par->colour= RED; |
|
683 |
right_rotate(parent[-1],par); |
|
684 |
parent[0]= &w->right; |
|
685 |
*++parent= &par->right; |
|
686 |
w= par->left; |
|
687 |
}
|
|
688 |
if (w->right->colour == BLACK && w->left->colour == BLACK) |
|
689 |
{
|
|
690 |
w->colour= RED; |
|
691 |
x= par; |
|
692 |
parent--; |
|
693 |
}
|
|
694 |
else
|
|
695 |
{
|
|
696 |
if (w->left->colour == BLACK) |
|
697 |
{
|
|
698 |
w->right->colour= BLACK; |
|
699 |
w->colour= RED; |
|
700 |
left_rotate(&par->left,w); |
|
701 |
w= par->left; |
|
702 |
}
|
|
703 |
w->colour= par->colour; |
|
704 |
par->colour= BLACK; |
|
705 |
w->left->colour= BLACK; |
|
706 |
right_rotate(parent[-1],par); |
|
707 |
x= tree->root; |
|
708 |
break; |
|
709 |
}
|
|
710 |
}
|
|
711 |
}
|
|
712 |
x->colour= BLACK; |
|
713 |
}
|
|
714 |
||
715 |
} /* namespace drizzled */ |