import RT-Thread@9217865c without bsp, libcpu and components/net

components/utilities/libadt/avl.h

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2006-2020, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2019-10-12     Jesven       first version
+ * 2022-11-14     WangXiaoyao  Optimize for generic use case
+ *                             and performance
+ */
+#ifndef __UTIL_TREE_AVL_H__
+#define __UTIL_TREE_AVL_H__
+
+#include <rtdef.h>
+#include <stdint.h>
+
+struct util_avl_struct
+{
+    struct util_avl_struct *avl_left;
+    struct util_avl_struct *avl_right;
+    struct util_avl_struct *parent;
+    size_t height;
+};
+
+#define AVL_ROOT ((struct util_avl_struct *)0)
+
+struct util_avl_root
+{
+    struct util_avl_struct *root_node;
+};
+
+void util_avl_rebalance(struct util_avl_struct *node,
+                        struct util_avl_root *root);
+
+void util_avl_remove(struct util_avl_struct *node, struct util_avl_root *root);
+
+static inline void util_avl_link(struct util_avl_struct *new_node,
+                                 struct util_avl_struct *parent,
+                                 struct util_avl_struct **nodeplace)
+{
+    new_node->avl_left = AVL_ROOT;
+    new_node->avl_right = AVL_ROOT;
+    new_node->parent = parent;
+    new_node->height = 1;
+    *nodeplace = new_node;
+}
+
+static inline struct util_avl_struct *util_avl_next(
+    struct util_avl_struct *node)
+{
+    struct util_avl_struct *successor = 0;
+    if (node)
+    {
+        if (node->avl_right)
+        {
+            node = node->avl_right;
+            while (node->avl_left)
+                node = node->avl_left;
+            successor = node;
+        }
+        else
+        {
+            while ((successor = node->parent) && (node == successor->avl_right))
+                node = successor;
+        }
+    }
+    return successor;
+}
+
+static inline struct util_avl_struct *util_avl_prev(
+    struct util_avl_struct *node)
+{
+    struct util_avl_struct *predecessor = 0;
+    if (node)
+    {
+        if (node->avl_left)
+        {
+            node = node->avl_left;
+            while (node->avl_right)
+                node = node->avl_right;
+            predecessor = node;
+        }
+        else
+        {
+            while ((predecessor = node->parent) &&
+                   (node == predecessor->avl_left))
+                node = predecessor;
+        }
+    }
+    return predecessor;
+}
+
+static inline struct util_avl_struct *util_avl_first(struct util_avl_root *root)
+{
+    struct util_avl_struct *first = root->root_node;
+    if (first)
+    {
+        while (first->avl_left)
+            first = first->avl_left;
+    }
+    return first;
+}
+
+static inline struct util_avl_struct *util_avl_last(struct util_avl_root *root)
+{
+    struct util_avl_struct *last = root->root_node;
+    if (last)
+    {
+        while (last->avl_right)
+            last = last->avl_right;
+    }
+    return last;
+}
+
+#endif /* __UTIL_TREE_AVL_H__ */