include: Add a generic red-black tree.
Henri Verbeet
hverbeet at codeweavers.com
Wed Jun 3 03:47:26 CDT 2009
---
include/wine/rbtree.h | 342 +++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 342 insertions(+), 0 deletions(-)
create mode 100644 include/wine/rbtree.h
diff --git a/include/wine/rbtree.h b/include/wine/rbtree.h
new file mode 100644
index 0000000..de29d10
--- /dev/null
+++ b/include/wine/rbtree.h
@@ -0,0 +1,342 @@
+/*
+ * Red-black search tree support
+ *
+ * Copyright 2009 Henri Verbeet
+ * Copyright 2009 Andrew Riedi
+ *
+ * This 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.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifndef __WINE_WINE_RBTREE_H
+#define __WINE_WINE_RBTREE_H
+
+#define WINE_RB_ENTRY_VALUE(element, type, field) \
+ ((type *)((char *)(element) - FIELD_OFFSET(type, field)))
+
+struct wine_rb_entry
+{
+ struct wine_rb_entry *left;
+ struct wine_rb_entry *right;
+ unsigned int flags;
+};
+
+struct wine_rb_stack
+{
+ struct wine_rb_entry ***entries;
+ size_t count;
+ size_t size;
+};
+
+struct wine_rb_functions
+{
+ void *(*alloc)(size_t size);
+ void *(*realloc)(void *ptr, size_t size);
+ void (*free)(void *ptr);
+ int (*compare)(const void *key, const struct wine_rb_entry *entry);
+};
+
+struct wine_rb_tree
+{
+ const struct wine_rb_functions *functions;
+ struct wine_rb_entry *root;
+ struct wine_rb_stack stack;
+};
+
+typedef void (wine_rb_traverse_func_t)(struct wine_rb_entry *entry, void *context);
+
+#define WINE_RB_FLAG_RED 0x1
+#define WINE_RB_FLAG_STOP 0x2
+#define WINE_RB_FLAG_TRAVERSED_LEFT 0x4
+#define WINE_RB_FLAG_TRAVERSED_RIGHT 0x8
+
+static inline void wine_rb_stack_clear(struct wine_rb_stack *stack)
+{
+ stack->count = 0;
+}
+
+static inline void wine_rb_stack_push(struct wine_rb_stack *stack, struct wine_rb_entry **entry)
+{
+ stack->entries[stack->count++] = entry;
+}
+
+static inline int wine_rb_ensure_stack_size(struct wine_rb_tree *tree, size_t size)
+{
+ struct wine_rb_stack *stack = &tree->stack;
+
+ if (size > stack->size)
+ {
+ size_t new_size = stack->size << 1;
+ struct wine_rb_entry ***new_entries = tree->functions->realloc(stack->entries,
+ new_size * sizeof(*stack->entries));
+
+ if (!new_entries) return -1;
+
+ stack->entries = new_entries;
+ stack->size = new_size;
+ }
+
+ return 0;
+}
+
+static inline int wine_rb_is_red(struct wine_rb_entry *entry)
+{
+ return entry && (entry->flags & WINE_RB_FLAG_RED);
+}
+
+static inline void wine_rb_rotate_left(struct wine_rb_entry **entry)
+{
+ struct wine_rb_entry *e = *entry;
+ struct wine_rb_entry *right = e->right;
+
+ e->right = right->left;
+ right->left = e;
+ right->flags &= ~WINE_RB_FLAG_RED;
+ right->flags |= e->flags & WINE_RB_FLAG_RED;
+ e->flags |= WINE_RB_FLAG_RED;
+ *entry = right;
+}
+
+static inline void wine_rb_rotate_right(struct wine_rb_entry **entry)
+{
+ struct wine_rb_entry *e = *entry;
+ struct wine_rb_entry *left = e->left;
+
+ e->left = left->right;
+ left->right = e;
+ left->flags &= ~WINE_RB_FLAG_RED;
+ left->flags |= e->flags & WINE_RB_FLAG_RED;
+ e->flags |= WINE_RB_FLAG_RED;
+ *entry = left;
+}
+
+static inline void wine_rb_flip_color(struct wine_rb_entry *entry)
+{
+ entry->flags ^= WINE_RB_FLAG_RED;
+ entry->left->flags ^= WINE_RB_FLAG_RED;
+ entry->right->flags ^= WINE_RB_FLAG_RED;
+}
+
+static inline void wine_rb_fixup(struct wine_rb_stack *stack)
+{
+ while (stack->count)
+ {
+ struct wine_rb_entry **entry = stack->entries[stack->count - 1];
+
+ if ((*entry)->flags & WINE_RB_FLAG_STOP)
+ {
+ (*entry)->flags &= ~WINE_RB_FLAG_STOP;
+ return;
+ }
+
+ if (wine_rb_is_red((*entry)->right) && !wine_rb_is_red((*entry)->left)) wine_rb_rotate_left(entry);
+ if (wine_rb_is_red((*entry)->left) && wine_rb_is_red((*entry)->left->left)) wine_rb_rotate_right(entry);
+ if (wine_rb_is_red((*entry)->left) && wine_rb_is_red((*entry)->right)) wine_rb_flip_color(*entry);
+ --stack->count;
+ }
+}
+
+static inline void wine_rb_move_red_left(struct wine_rb_entry **entry)
+{
+ wine_rb_flip_color(*entry);
+ if (wine_rb_is_red((*entry)->right->left))
+ {
+ wine_rb_rotate_right(&(*entry)->right);
+ wine_rb_rotate_left(entry);
+ wine_rb_flip_color(*entry);
+ }
+}
+
+static inline void wine_rb_move_red_right(struct wine_rb_entry **entry)
+{
+ wine_rb_flip_color(*entry);
+ if (wine_rb_is_red((*entry)->left->left))
+ {
+ wine_rb_rotate_right(entry);
+ wine_rb_flip_color(*entry);
+ }
+}
+
+static inline void wine_rb_postorder(struct wine_rb_tree *tree, wine_rb_traverse_func_t *callback, void *context)
+{
+ struct wine_rb_entry **entry;
+
+ if (!tree->root) return;
+
+ for (entry = &tree->root;;)
+ {
+ struct wine_rb_entry *e = *entry;
+
+ if (e->left && !(e->flags & WINE_RB_FLAG_TRAVERSED_LEFT))
+ {
+ wine_rb_stack_push(&tree->stack, entry);
+ e->flags |= WINE_RB_FLAG_TRAVERSED_LEFT;
+ entry = &e->left;
+ continue;
+ }
+
+ if (e->right && !(e->flags & WINE_RB_FLAG_TRAVERSED_RIGHT))
+ {
+ wine_rb_stack_push(&tree->stack, entry);
+ e->flags |= WINE_RB_FLAG_TRAVERSED_RIGHT;
+ entry = &e->right;
+ continue;
+ }
+
+ e->flags &= ~(WINE_RB_FLAG_TRAVERSED_LEFT | WINE_RB_FLAG_TRAVERSED_RIGHT);
+ callback(e, context);
+
+ if (!tree->stack.count) break;
+ entry = tree->stack.entries[--tree->stack.count];
+ }
+}
+
+static inline int wine_rb_init(struct wine_rb_tree *tree, const struct wine_rb_functions *functions)
+{
+ tree->functions = functions;
+ tree->root = NULL;
+
+ tree->stack.entries = functions->alloc(16 * sizeof(*tree->stack.entries));
+ if (!tree->stack.entries) return -1;
+ tree->stack.size = 16;
+ tree->stack.count = 0;
+
+ return 0;
+}
+
+static inline void wine_rb_for_each_entry(struct wine_rb_tree *tree, wine_rb_traverse_func_t *callback, void *context)
+{
+ wine_rb_postorder(tree, callback, context);
+}
+
+static inline void wine_rb_destroy(struct wine_rb_tree *tree, wine_rb_traverse_func_t *callback, void *context)
+{
+ /* Note that we use postorder here because the callback will likely free the entry. */
+ if (callback) wine_rb_postorder(tree, callback, context);
+
+ tree->root = NULL;
+ tree->functions->free(tree->stack.entries);
+}
+
+static inline struct wine_rb_entry *wine_rb_get(const struct wine_rb_tree *tree, const void *key)
+{
+ struct wine_rb_entry *entry = tree->root;
+ while (entry)
+ {
+ int c = tree->functions->compare(key, entry);
+ if (!c) return entry;
+ entry = c < 0 ? entry->left : entry->right;
+ }
+ return NULL;
+}
+
+static inline int wine_rb_put(struct wine_rb_tree *tree, const void *key, struct wine_rb_entry *entry)
+{
+ struct wine_rb_entry **parent = &tree->root;
+ size_t black_height = 1;
+
+ while (*parent)
+ {
+ int c;
+
+ if (!wine_rb_is_red(*parent)) ++black_height;
+
+ wine_rb_stack_push(&tree->stack, parent);
+
+ c = tree->functions->compare(key, *parent);
+ if (!c)
+ {
+ wine_rb_stack_clear(&tree->stack);
+ return -1;
+ }
+ else if (c < 0) parent = &(*parent)->left;
+ else parent = &(*parent)->right;
+ }
+
+ /* After insertion, the path length to any node should be <= (black_height + 1) * 2. */
+ if (wine_rb_ensure_stack_size(tree, black_height << 1) == -1)
+ {
+ wine_rb_stack_clear(&tree->stack);
+ return -1;
+ }
+
+ entry->flags = WINE_RB_FLAG_RED;
+ entry->left = NULL;
+ entry->right = NULL;
+ *parent = entry;
+
+ wine_rb_fixup(&tree->stack);
+ tree->root->flags &= ~WINE_RB_FLAG_RED;
+
+ return 0;
+}
+
+static inline void wine_rb_remove(struct wine_rb_tree *tree, const void *key)
+{
+ struct wine_rb_entry **entry = &tree->root;
+
+ while (*entry)
+ {
+ if (tree->functions->compare(key, *entry) < 0)
+ {
+ wine_rb_stack_push(&tree->stack, entry);
+ if (!wine_rb_is_red((*entry)->left) && !wine_rb_is_red((*entry)->left->left)) wine_rb_move_red_left(entry);
+ entry = &(*entry)->left;
+ }
+ else
+ {
+ if (wine_rb_is_red((*entry)->left)) wine_rb_rotate_right(entry);
+ if (!tree->functions->compare(key, *entry) && !(*entry)->right)
+ {
+ *entry = NULL;
+ break;
+ }
+ if (!wine_rb_is_red((*entry)->right) && !wine_rb_is_red((*entry)->right->left))
+ wine_rb_move_red_right(entry);
+ if (!tree->functions->compare(key, *entry))
+ {
+ struct wine_rb_entry **e = &(*entry)->right;
+ struct wine_rb_entry *m = *e;
+ while (m->left) m = m->left;
+
+ wine_rb_stack_push(&tree->stack, entry);
+ (*entry)->flags |= WINE_RB_FLAG_STOP;
+
+ while ((*e)->left)
+ {
+ wine_rb_stack_push(&tree->stack, e);
+ if (!wine_rb_is_red((*e)->left) && !wine_rb_is_red((*e)->left->left)) wine_rb_move_red_left(e);
+ e = &(*e)->left;
+ }
+ *e = NULL;
+ wine_rb_fixup(&tree->stack);
+
+ *m = **entry;
+ *entry = m;
+
+ break;
+ }
+ else
+ {
+ wine_rb_stack_push(&tree->stack, entry);
+ entry = &(*entry)->right;
+ }
+ }
+ }
+
+ wine_rb_fixup(&tree->stack);
+ if (tree->root) tree->root->flags &= ~WINE_RB_FLAG_RED;
+}
+
+#endif /* __WINE_WINE_RBTREE_H */
--
1.6.0.6
--------------000702030508090807020006--
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