From 71da024e55011b99cd67e09eb1773b764d718a65 Mon Sep 17 00:00:00 2001
From: Benign X <1341398182@qq.com>
Date: Thu, 30 Nov 2023 16:42:39 +0800
Subject: [PATCH] feat(lv_rb_t): add red black tree to lvgl (#4585)

---
 lvgl.h           |   1 +
 src/misc/lv_rb.c | 520 +++++++++++++++++++++++++++++++++++++++++++++++
 src/misc/lv_rb.h |  78 +++++++
 3 files changed, 599 insertions(+)
 create mode 100644 src/misc/lv_rb.c
 create mode 100644 src/misc/lv_rb.h

diff --git a/lvgl.h b/lvgl.h
index 9f69d372a..bff014939 100644
--- a/lvgl.h
+++ b/lvgl.h
@@ -34,6 +34,7 @@ extern "C" {
 #include "src/misc/lv_async.h"
 #include "src/misc/lv_anim_timeline.h"
 #include "src/misc/lv_profiler_builtin.h"
+#include "src/misc/lv_rb.h"
 
 #include "src/tick/lv_tick.h"
 
diff --git a/src/misc/lv_rb.c b/src/misc/lv_rb.c
new file mode 100644
index 000000000..f9ee98d11
--- /dev/null
+++ b/src/misc/lv_rb.c
@@ -0,0 +1,520 @@
+/**
+ * @file lv_rb.c
+ *
+ */
+
+/*********************
+ *      INCLUDES
+ *********************/
+#include "lv_rb.h"
+#include "../stdlib/lv_string.h"
+
+/*********************
+ *      DEFINES
+ *********************/
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ *  STATIC PROTOTYPES
+ **********************/
+
+static lv_rb_node_t * rb_create_node(lv_rb_t * tree);
+static lv_rb_node_t * rb_find_leaf_parent(lv_rb_t * tree, lv_rb_node_t * node);
+static void rb_right_rotate(lv_rb_t * tree, lv_rb_node_t * node);
+static void rb_left_rotate(lv_rb_t * tree, lv_rb_node_t * node);
+static void rb_insert_color(lv_rb_t * tree, lv_rb_node_t * node);
+static void rb_delete_color(lv_rb_t * tree, lv_rb_node_t * node1, lv_rb_node_t * node2);
+
+/**********************
+ *  GLOBAL VARIABLES
+ **********************/
+
+/**********************
+ *  STATIC VARIABLES
+ **********************/
+
+/**********************
+ *      MACROS
+ **********************/
+
+/**********************
+ *   GLOBAL FUNCTIONS
+ **********************/
+
+bool lv_rb_init(lv_rb_t * tree, lv_rb_compare_t compare, size_t node_size)
+{
+    LV_ASSERT_NULL(tree);
+    LV_ASSERT_NULL(compare);
+    LV_ASSERT(node_size > 0);
+
+    if(tree == NULL || compare == NULL || node_size == 0) {
+        return false;
+    }
+
+    lv_memzero(tree, sizeof(lv_rb_t));
+
+    tree->root = NULL;
+    tree->compare = compare;
+    tree->size = node_size;
+
+    return true;
+}
+
+lv_rb_node_t * lv_rb_insert(lv_rb_t * tree, void * key)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return NULL;
+    }
+
+    lv_rb_node_t * node = lv_rb_find(tree, key);
+    if(node) return node;
+    else {
+        node = rb_create_node(tree);
+        if(node == NULL) return NULL;
+
+        if(tree->root == NULL) {
+            tree->root = node;
+            node->parent = NULL;
+            node->color = LV_RB_COLOR_BLACK;
+            return node;
+        }
+    }
+
+    void * new_data = node->data;
+    node->data = key;
+    lv_rb_node_t * parent = rb_find_leaf_parent(tree, node);
+
+    node->parent = parent;
+    node->color = LV_RB_COLOR_RED;
+
+    if(tree->compare(key, parent->data) < 0) parent->left = node;
+    else parent->right = node;
+
+    rb_insert_color(tree, node);
+
+    node->data = new_data;
+    return node;
+}
+
+lv_rb_node_t * lv_rb_find(lv_rb_t * tree, const void * key)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return NULL;
+    }
+
+    lv_rb_node_t * current = tree->root;
+
+    while(current != NULL) {
+        lv_rb_compare_res_t cmp = tree->compare(key, current->data);
+
+        if(cmp == 0) {
+            return current;
+        }
+        else if(cmp < 0) {
+            current = current->left;
+        }
+        else {
+            current = current->right;
+        }
+    }
+
+    return NULL;
+}
+
+bool lv_rb_remove(lv_rb_t * tree, const void * key)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return false;
+    }
+
+    lv_rb_node_t * node = lv_rb_find(tree, key);
+    LV_ASSERT_NULL(node);
+    if(node == NULL) {
+        LV_LOG_WARN("rb delete %d not found", (int)(uintptr_t)key);
+        return false;
+    }
+
+    lv_rb_node_t * child = NULL;
+    lv_rb_node_t * parent = NULL;
+    lv_rb_color_t color = LV_RB_COLOR_BLACK;
+
+    if(node->left != NULL && node->right != NULL) {
+        lv_rb_node_t * replace = node;
+        replace = lv_rb_minimum_from(replace->right);
+
+        if(node->parent != NULL) {
+            if(node->parent->left == node) {
+                node->parent->left = replace;
+            }
+            else {
+                node->parent->right = replace;
+            }
+        }
+        else {
+            tree->root = replace;
+        }
+
+        child = replace->right;
+        parent = replace->parent;
+        color = replace->color;
+
+        if(parent == node) {
+            parent = replace;
+        }
+        else {
+            if(child != NULL) {
+                child->parent = parent;
+            }
+            parent->left = child;
+            replace->right = node->right;
+            node->right->parent = replace;
+        }
+
+        replace->parent = node->parent;
+        replace->color = node->color;
+        replace->left = node->left;
+        node->left->parent = replace;
+
+        if(color == LV_RB_COLOR_BLACK) {
+            rb_delete_color(tree, child, parent);
+        }
+
+        lv_free(node->data);
+        lv_free(node);
+        return true;
+    }
+
+    child = node->right != NULL ? node->right : node->left;
+    parent = node->parent;
+    color = node->color;
+
+    if(child != NULL) {
+        child->parent = parent;
+    }
+
+    if(parent != NULL) {
+        if(parent->left == node) {
+            parent->left = child;
+        }
+        else {
+            parent->right = child;
+        }
+    }
+    else {
+        tree->root = child;
+    }
+
+    if(color == LV_RB_COLOR_BLACK) {
+        rb_delete_color(tree, child, parent);
+    }
+
+    lv_free(node->data);
+    lv_free(node);
+    return true;
+}
+
+void lv_rb_destroy(lv_rb_t * tree)
+{
+    LV_ASSERT_NULL(tree);
+
+    if(tree == NULL) {
+        return;
+    }
+
+    lv_rb_node_t * node = tree->root;
+    lv_rb_node_t * parent = NULL;
+
+    while(node != NULL) {
+        if(node->left != NULL) {
+            node = node->left;
+        }
+        else if(node->right != NULL) {
+            node = node->right;
+        }
+        else {
+            parent = node->parent;
+            if(parent != NULL) {
+                if(parent->left == node) {
+                    parent->left = NULL;
+                }
+                else {
+                    parent->right = NULL;
+                }
+            }
+            lv_free(node->data);
+            lv_free(node);
+            node = parent;
+        }
+    }
+}
+
+lv_rb_node_t * lv_rb_minimum(lv_rb_t * tree)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return NULL;
+    }
+    return lv_rb_minimum_from(tree->root);
+}
+
+lv_rb_node_t * lv_rb_maximum(lv_rb_t * tree)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return NULL;
+    }
+    return lv_rb_maximum_from(tree->root);
+}
+
+lv_rb_node_t * lv_rb_minimum_from(lv_rb_node_t * node)
+{
+    while(node->left != NULL) {
+        node = node->left;
+    }
+
+    return node;
+}
+
+lv_rb_node_t * lv_rb_maximum_from(lv_rb_node_t * node)
+{
+    while(node->right != NULL) {
+        node = node->right;
+    }
+
+    return node;
+}
+
+/**********************
+ *   STATIC FUNCTIONS
+ **********************/
+
+static lv_rb_node_t * rb_create_node(lv_rb_t * tree)
+{
+    lv_rb_node_t * node = lv_malloc(sizeof(lv_rb_node_t));
+    LV_ASSERT_MALLOC(node);
+    if(node == NULL) {
+        return NULL;
+    }
+
+    node->data = lv_malloc(tree->size);
+    LV_ASSERT_MALLOC(node->data);
+    if(node->data == NULL) {
+        lv_free(node);
+        return NULL;
+    }
+
+    node->color = LV_RB_COLOR_RED;
+    node->left = NULL;
+    node->right = NULL;
+
+    return node;
+}
+
+static lv_rb_node_t * rb_find_leaf_parent(lv_rb_t * tree, lv_rb_node_t * node)
+{
+    lv_rb_node_t * current = tree->root;
+    lv_rb_node_t * parent = current;
+
+    while(current != NULL) {
+        parent = current;
+
+        if(tree->compare(node->data, current->data) < 0) {
+            current = current->left;
+        }
+        else {
+            current = current->right;
+        }
+    }
+
+    return parent;
+}
+
+static void rb_right_rotate(lv_rb_t * tree, lv_rb_node_t * node)
+{
+    lv_rb_node_t * left = node->left;
+    node->left = left->right;
+
+    if(left->right != NULL) {
+        left->right->parent = node;
+    }
+
+    left->parent = node->parent;
+
+    if(node->parent == NULL) {
+        tree->root = left;
+    }
+    else if(node == node->parent->right) {
+        node->parent->right = left;
+    }
+    else {
+        node->parent->left = left;
+    }
+
+    left->right = node;
+    node->parent = left;
+}
+
+static void rb_left_rotate(lv_rb_t * tree, lv_rb_node_t * node)
+{
+    lv_rb_node_t * right = node->right;
+    node->right = right->left;
+
+    if(right->left != NULL) {
+        right->left->parent = node;
+    }
+
+    right->parent = node->parent;
+
+    if(node->parent == NULL) {
+        tree->root = right;
+    }
+    else if(node == node->parent->left) {
+        node->parent->left = right;
+    }
+    else {
+        node->parent->right = right;
+    }
+
+    right->left = node;
+    node->parent = right;
+}
+
+static void rb_insert_color(lv_rb_t * tree, lv_rb_node_t * node)
+{
+    lv_rb_node_t * parent = NULL;
+    lv_rb_node_t * gparent = NULL;
+
+    while((parent = node->parent) && parent->color == LV_RB_COLOR_RED) {
+        gparent = parent->parent;
+
+        if(parent == gparent->left) {
+            {
+                lv_rb_node_t * uncle = gparent->right;
+                if(uncle && uncle->color == LV_RB_COLOR_RED) {
+                    uncle->color = LV_RB_COLOR_BLACK;
+                    parent->color = LV_RB_COLOR_BLACK;
+                    gparent->color = LV_RB_COLOR_RED;
+                    node = gparent;
+                    continue;
+                }
+            }
+
+            if(parent->right == node) {
+                lv_rb_node_t * tmp;
+                rb_left_rotate(tree, parent);
+                tmp = parent;
+                parent = node;
+                node = tmp;
+            }
+
+            parent->color = LV_RB_COLOR_BLACK;
+            gparent->color = LV_RB_COLOR_RED;
+            rb_right_rotate(tree, gparent);
+        }
+        else {
+            {
+                lv_rb_node_t * uncle = gparent->left;
+                if(uncle && uncle->color == LV_RB_COLOR_RED) {
+                    uncle->color = LV_RB_COLOR_BLACK;
+                    parent->color = LV_RB_COLOR_BLACK;
+                    gparent->color = LV_RB_COLOR_RED;
+                    node = gparent;
+                    continue;
+                }
+            }
+
+            if(parent->left == node) {
+                lv_rb_node_t * tmp;
+                rb_right_rotate(tree, parent);
+                tmp = parent;
+                parent = node;
+                node = tmp;
+            }
+
+            parent->color = LV_RB_COLOR_BLACK;
+            gparent->color = LV_RB_COLOR_RED;
+            rb_left_rotate(tree, gparent);
+        }
+    }
+
+    tree->root->color = LV_RB_COLOR_BLACK;
+}
+
+static void rb_delete_color(lv_rb_t * tree, lv_rb_node_t * node1, lv_rb_node_t * node2)
+{
+    LV_ASSERT_NULL(tree);
+    if(tree == NULL) {
+        return;
+    }
+
+    while((node1 == NULL || node1->color == LV_RB_COLOR_BLACK) && node1 != tree->root) {
+        if(node2->left == node1) {
+            lv_rb_node_t * pNode2 = node2->right;
+            if(pNode2->color == LV_RB_COLOR_RED) {
+                pNode2->color = LV_RB_COLOR_BLACK;
+                node2->color = LV_RB_COLOR_RED;
+                rb_left_rotate(tree, node2);
+                pNode2 = node2->right;
+            }
+
+            if((pNode2->left == NULL || pNode2->left->color == LV_RB_COLOR_BLACK)
+               && (pNode2->right == NULL || pNode2->right->color == LV_RB_COLOR_BLACK)) {
+                pNode2->color = LV_RB_COLOR_RED;
+                node1 = node2;
+                node2 = node2->parent;
+            }
+            else {
+                if(pNode2->right == NULL || pNode2->right->color == LV_RB_COLOR_BLACK) {
+                    pNode2->left->color = LV_RB_COLOR_BLACK;
+                    pNode2->color = LV_RB_COLOR_RED;
+                    rb_right_rotate(tree, pNode2);
+                    pNode2 = node2->right;
+                }
+                pNode2->color = node2->color;
+                node2->color = LV_RB_COLOR_BLACK;
+                pNode2->right->color = LV_RB_COLOR_BLACK;
+                rb_left_rotate(tree, node2);
+                node1 = tree->root;
+                break;
+            }
+        }
+        else {
+            lv_rb_node_t * pNode2 = node2->left;
+            if(pNode2->color == LV_RB_COLOR_RED) {
+                pNode2->color = LV_RB_COLOR_BLACK;
+                node2->color = LV_RB_COLOR_RED;
+                rb_right_rotate(tree, node2);
+                pNode2 = node2->left;
+            }
+
+            if((pNode2->left == NULL || pNode2->left->color == LV_RB_COLOR_BLACK)
+               && (pNode2->right == NULL || pNode2->right->color == LV_RB_COLOR_BLACK)) {
+                pNode2->color = LV_RB_COLOR_RED;
+                node1 = node2;
+                node2 = node2->parent;
+            }
+            else {
+                if(pNode2->left == NULL || pNode2->left->color == LV_RB_COLOR_BLACK) {
+                    pNode2->right->color = LV_RB_COLOR_BLACK;
+                    pNode2->color = LV_RB_COLOR_RED;
+                    rb_left_rotate(tree, pNode2);
+                    pNode2 = node2->left;
+                }
+                pNode2->color = node2->color;
+                node2->color = LV_RB_COLOR_BLACK;
+                pNode2->left->color = LV_RB_COLOR_BLACK;
+                rb_right_rotate(tree, node2);
+                node1 = tree->root;
+                break;
+            }
+        }
+    }
+    if(node1 != NULL)
+        node1->color = LV_RB_COLOR_BLACK;
+}
diff --git a/src/misc/lv_rb.h b/src/misc/lv_rb.h
new file mode 100644
index 000000000..c266b1f1e
--- /dev/null
+++ b/src/misc/lv_rb.h
@@ -0,0 +1,78 @@
+/**
+ * @file lv_rb.h
+ *
+ */
+
+
+#ifndef LV_RB_H
+#define LV_RB_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*********************
+ *      INCLUDES
+ *********************/
+#include "lv_types.h"
+#include "stdbool.h"
+#include "lv_assert.h"
+
+/*********************
+ *      DEFINES
+ *********************/
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+typedef enum {
+    LV_RB_COLOR_RED,
+    LV_RB_COLOR_BLACK
+} lv_rb_color_t;
+
+typedef struct lv_rb_node_t {
+    struct lv_rb_node_t * parent;
+    struct lv_rb_node_t * left;
+    struct lv_rb_node_t * right;
+    lv_rb_color_t color;
+    void * data;
+} lv_rb_node_t;
+
+typedef int8_t lv_rb_compare_res_t;
+
+typedef lv_rb_compare_res_t (*lv_rb_compare_t)(const void * a, const void * b);
+
+typedef struct {
+    lv_rb_node_t * root;
+    lv_rb_compare_t compare;
+    size_t size;
+} lv_rb_t;
+
+/**********************
+ * GLOBAL PROTOTYPES
+ **********************/
+
+bool lv_rb_init(lv_rb_t * tree, lv_rb_compare_t compare, size_t node_size);
+lv_rb_node_t * lv_rb_insert(lv_rb_t * tree, void * key);
+lv_rb_node_t * lv_rb_find(lv_rb_t * tree, const void * key);
+bool lv_rb_remove(lv_rb_t * tree, const void * key);
+lv_rb_node_t * lv_rb_minimum(lv_rb_t * node);
+lv_rb_node_t * lv_rb_maximum(lv_rb_t * node);
+lv_rb_node_t * lv_rb_minimum_from(lv_rb_node_t * node);
+lv_rb_node_t * lv_rb_maximum_from(lv_rb_node_t * node);
+void lv_rb_destroy(lv_rb_t * tree);
+
+/*************************
+ *    GLOBAL VARIABLES
+ *************************/
+
+/**********************
+ *      MACROS
+ **********************/
+
+#ifdef __cplusplus
+} /*extern "C"*/
+#endif
+
+#endif /*LV_RB_H*/