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-rw-r--r--3rdparty/plibsys/src/ptree-rb.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/3rdparty/plibsys/src/ptree-rb.c b/3rdparty/plibsys/src/ptree-rb.c
new file mode 100644
index 0000000..53c7b09
--- /dev/null
+++ b/3rdparty/plibsys/src/ptree-rb.c
@@ -0,0 +1,484 @@
+/*
+ * The MIT License
+ *
+ * Copyright (C) 2015-2016 Alexander Saprykin <saprykin.spb@gmail.com>
+ * Illustrations have been taken from the Linux kernel rbtree.c
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * 'Software'), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "pmem.h"
+#include "ptree-rb.h"
+
+typedef enum PTreeRBColor_ {
+ P_TREE_RB_COLOR_RED = 0x01,
+ P_TREE_RB_COLOR_BLACK = 0x02
+} PTreeRBColor;
+
+typedef struct PTreeRBNode_ {
+ struct PTreeBaseNode_ base;
+ struct PTreeRBNode_ *parent;
+ PTreeRBColor color;
+} PTreeRBNode;
+
+static pboolean pp_tree_rb_is_black (PTreeRBNode *node);
+static pboolean pp_tree_rb_is_red (PTreeRBNode *node);
+static PTreeRBNode * pp_tree_rb_get_gparent (PTreeRBNode *node);
+static PTreeRBNode * pp_tree_rb_get_uncle (PTreeRBNode *node);
+static PTreeRBNode * pp_tree_rb_get_sibling (PTreeRBNode *node);
+static void pp_tree_rb_rotate_left (PTreeRBNode *node, PTreeBaseNode **root);
+static void pp_tree_rb_rotate_right (PTreeRBNode *node, PTreeBaseNode **root);
+static void pp_tree_rb_balance_insert (PTreeRBNode *node, PTreeBaseNode **root);
+static void pp_tree_rb_balance_remove (PTreeRBNode *node, PTreeBaseNode **root);
+
+static pboolean
+pp_tree_rb_is_black (PTreeRBNode *node)
+{
+ if (node == NULL)
+ return TRUE;
+
+ return ((node->color) & P_TREE_RB_COLOR_BLACK) > 0 ? TRUE : FALSE;
+}
+
+static pboolean
+pp_tree_rb_is_red (PTreeRBNode *node)
+{
+ return ((node->color) & P_TREE_RB_COLOR_RED) > 0 ? TRUE : FALSE;
+}
+
+static PTreeRBNode *
+pp_tree_rb_get_gparent (PTreeRBNode *node)
+{
+ return node->parent->parent;
+}
+
+static PTreeRBNode *
+pp_tree_rb_get_uncle (PTreeRBNode *node)
+{
+ PTreeRBNode *gparent = pp_tree_rb_get_gparent (node);
+
+ if ((PTreeRBNode *) gparent->base.left == node->parent)
+ return (PTreeRBNode *) gparent->base.right;
+ else
+ return (PTreeRBNode *) gparent->base.left;
+}
+
+static PTreeRBNode *
+pp_tree_rb_get_sibling (PTreeRBNode *node)
+{
+ if (node->parent->base.left == (PTreeBaseNode *) node)
+ return (PTreeRBNode *) node->parent->base.right;
+ else
+ return (PTreeRBNode *) node->parent->base.left;
+}
+
+static void
+pp_tree_rb_rotate_left (PTreeRBNode *node, PTreeBaseNode **root)
+{
+ PTreeBaseNode *tmp_node;
+
+ tmp_node = node->base.right;
+
+ if (P_LIKELY (node->parent != NULL)) {
+ if (node->parent->base.left == (PTreeBaseNode *) node)
+ node->parent->base.left = tmp_node;
+ else
+ node->parent->base.right = tmp_node;
+ }
+
+ node->base.right = tmp_node->left;
+
+ if (tmp_node->left != NULL)
+ ((PTreeRBNode *) tmp_node->left)->parent = node;
+
+ tmp_node->left = (PTreeBaseNode *) node;
+ ((PTreeRBNode *) tmp_node)->parent = node->parent;
+ node->parent = (PTreeRBNode *) tmp_node;
+
+ if (P_UNLIKELY (((PTreeRBNode *) tmp_node)->parent == NULL))
+ *root = tmp_node;
+}
+
+static void
+pp_tree_rb_rotate_right (PTreeRBNode *node, PTreeBaseNode **root)
+{
+ PTreeBaseNode *tmp_node;
+
+ tmp_node = node->base.left;
+
+ if (P_LIKELY (node->parent != NULL)) {
+ if (node->parent->base.left == (PTreeBaseNode *) node)
+ node->parent->base.left = tmp_node;
+ else
+ node->parent->base.right = tmp_node;
+ }
+
+ node->base.left = tmp_node->right;
+
+ if (tmp_node->right != NULL)
+ ((PTreeRBNode *) tmp_node->right)->parent = node;
+
+ tmp_node->right = (PTreeBaseNode *) node;
+ ((PTreeRBNode *) tmp_node)->parent = node->parent;
+ node->parent = (PTreeRBNode *) tmp_node;
+
+ if (P_UNLIKELY (((PTreeRBNode *) tmp_node)->parent == NULL))
+ *root = tmp_node;
+}
+
+static void
+pp_tree_rb_balance_insert (PTreeRBNode *node, PTreeBaseNode **root)
+{
+ PTreeRBNode *uncle;
+ PTreeRBNode *gparent;
+
+ while (TRUE) {
+ /* Case 1: We are at the root */
+ if (P_UNLIKELY (node->parent == NULL)) {
+ node->color = P_TREE_RB_COLOR_BLACK;
+ break;
+ }
+
+ /* Case 2: We have a black parent */
+ if (pp_tree_rb_is_black (node->parent) == TRUE)
+ break;
+
+ uncle = pp_tree_rb_get_uncle (node);
+ gparent = pp_tree_rb_get_gparent (node);
+
+ /* Case 3: Both parent and uncle are red, flip colors
+ *
+ * G g
+ * / \ / \
+ * p u --> P U
+ * / /
+ * n n
+ */
+ if (uncle != NULL && pp_tree_rb_is_red (uncle) == TRUE) {
+ node->parent->color = P_TREE_RB_COLOR_BLACK;
+ uncle->color = P_TREE_RB_COLOR_BLACK;
+ gparent->color = P_TREE_RB_COLOR_RED;
+
+ /* Continue iteratively from gparent */
+ node = gparent;
+ continue;
+ }
+
+ if (node->parent == (PTreeRBNode *) gparent->base.left) {
+ if (node == (PTreeRBNode *) node->parent->base.right) {
+ /* Case 4a: Left rotate at parent
+ *
+ * G G
+ * / \ / \
+ * p U --> n U
+ * \ /
+ * n p
+ */
+ pp_tree_rb_rotate_left (node->parent, root);
+
+ node = (PTreeRBNode *) node->base.left;
+ }
+
+ gparent->color = P_TREE_RB_COLOR_RED;
+ node->parent->color = P_TREE_RB_COLOR_BLACK;
+
+ /* Case 5a: Right rotate at gparent
+ *
+ * G P
+ * / \ / \
+ * p U --> n g
+ * / \
+ * n U
+ */
+ pp_tree_rb_rotate_right (gparent, root);
+
+ break;
+ } else {
+ if (node == (PTreeRBNode *) node->parent->base.left) {
+ /* Case 4b: Right rotate at parent */
+ pp_tree_rb_rotate_right (node->parent, root);
+
+ node = (PTreeRBNode *) node->base.right;
+ }
+
+ gparent->color = P_TREE_RB_COLOR_RED;
+ node->parent->color = P_TREE_RB_COLOR_BLACK;
+
+ /* Case 5b: Left rotate at gparent*/
+ pp_tree_rb_rotate_left (gparent, root);
+
+ break;
+ }
+ }
+}
+
+static void
+pp_tree_rb_balance_remove (PTreeRBNode *node, PTreeBaseNode **root)
+{
+ PTreeRBNode *sibling;
+
+ while (TRUE) {
+ /* Case 1: We are at the root */
+ if (P_UNLIKELY (node->parent == NULL))
+ break;
+
+ sibling = pp_tree_rb_get_sibling (node);
+
+ if (pp_tree_rb_is_red (sibling) == TRUE) {
+ /*
+ * Case 2: Left (right) rotate at parent
+ *
+ * P S
+ * / \ / \
+ * N s --> p Sr
+ * / \ / \
+ * Sl Sr N Sl
+ */
+ node->parent->color = P_TREE_RB_COLOR_RED;
+ sibling->color = P_TREE_RB_COLOR_BLACK;
+
+ if ((PTreeBaseNode *) node == node->parent->base.left)
+ pp_tree_rb_rotate_left (node->parent, root);
+ else
+ pp_tree_rb_rotate_right (node->parent, root);
+
+ sibling = pp_tree_rb_get_sibling (node);
+ }
+
+ /*
+ * Case 3: Sibling (parent) color flip
+ *
+ * (p) (p)
+ * / \ / \
+ * N S --> N s
+ * / \ / \
+ * Sl Sr Sl Sr
+ */
+ if (pp_tree_rb_is_black ((PTreeRBNode *) sibling->base.left) == TRUE &&
+ pp_tree_rb_is_black ((PTreeRBNode *) sibling->base.right) == TRUE) {
+ sibling->color = P_TREE_RB_COLOR_RED;
+
+ if (pp_tree_rb_is_black (node->parent) == TRUE) {
+ node = node->parent;
+ continue;
+ } else {
+ node->parent->color = P_TREE_RB_COLOR_BLACK;
+ break;
+ }
+ }
+
+ /*
+ * Case 4: Right (left) rotate at sibling
+ *
+ * (p) (p)
+ * / \ / \
+ * N S --> N Sl
+ * / \ \
+ * sl Sr s
+ * \
+ * Sr
+ */
+ if ((PTreeBaseNode *) node == node->parent->base.left &&
+ pp_tree_rb_is_black ((PTreeRBNode *) sibling->base.right) == TRUE) {
+ sibling->color = P_TREE_RB_COLOR_RED;
+ ((PTreeRBNode *) sibling->base.left)->color = P_TREE_RB_COLOR_BLACK;
+
+ pp_tree_rb_rotate_right (sibling, root);
+
+ sibling = pp_tree_rb_get_sibling (node);
+ } else if ((PTreeBaseNode *) node == node->parent->base.right &&
+ pp_tree_rb_is_black ((PTreeRBNode *) sibling->base.left) == TRUE) {
+ sibling->color = P_TREE_RB_COLOR_RED;
+ ((PTreeRBNode *) sibling->base.right)->color = P_TREE_RB_COLOR_BLACK;
+
+ pp_tree_rb_rotate_left (sibling, root);
+
+ sibling = pp_tree_rb_get_sibling (node);
+ }
+
+ /*
+ * Case 5: Left (right) rotate at parent and color flips
+ *
+ * (p) (s)
+ * / \ / \
+ * N S --> P Sr
+ * / \ / \
+ * (sl) sr N (sl)
+ */
+ sibling->color = node->parent->color;
+ node->parent->color = P_TREE_RB_COLOR_BLACK;
+
+ if ((PTreeBaseNode *) node == node->parent->base.left) {
+ ((PTreeRBNode *) sibling->base.right)->color = P_TREE_RB_COLOR_BLACK;
+ pp_tree_rb_rotate_left (node->parent, root);
+ } else {
+ ((PTreeRBNode *) sibling->base.left)->color = P_TREE_RB_COLOR_BLACK;
+ pp_tree_rb_rotate_right (node->parent, root);
+ }
+
+ break;
+ }
+}
+
+pboolean
+p_tree_rb_insert (PTreeBaseNode **root_node,
+ PCompareDataFunc compare_func,
+ ppointer data,
+ PDestroyFunc key_destroy_func,
+ PDestroyFunc value_destroy_func,
+ ppointer key,
+ ppointer value)
+{
+ PTreeBaseNode **cur_node;
+ PTreeBaseNode *parent_node;
+ pint cmp_result;
+
+ cur_node = root_node;
+ parent_node = *root_node;
+
+ /* Find where to insert the node */
+ while (*cur_node != NULL) {
+ cmp_result = compare_func (key, (*cur_node)->key, data);
+
+ if (cmp_result < 0) {
+ parent_node = *cur_node;
+ cur_node = &(*cur_node)->left;
+ } else if (cmp_result > 0) {
+ parent_node = *cur_node;
+ cur_node = &(*cur_node)->right;
+ } else
+ break;
+ }
+
+ /* If we have existing one - replace a key-value pair */
+ if (*cur_node != NULL) {
+ if (key_destroy_func != NULL)
+ key_destroy_func ((*cur_node)->key);
+
+ if (value_destroy_func != NULL)
+ value_destroy_func ((*cur_node)->value);
+
+ (*cur_node)->key = key;
+ (*cur_node)->value = value;
+
+ return FALSE;
+ }
+
+ if (P_UNLIKELY ((*cur_node = p_malloc0 (sizeof (PTreeRBNode))) == NULL))
+ return FALSE;
+
+ (*cur_node)->key = key;
+ (*cur_node)->value = value;
+
+ ((PTreeRBNode *) *cur_node)->color = P_TREE_RB_COLOR_RED;
+ ((PTreeRBNode *) *cur_node)->parent = (PTreeRBNode *) parent_node;
+
+ /* Balance the tree */
+ pp_tree_rb_balance_insert ((PTreeRBNode *) *cur_node, root_node);
+
+ return TRUE;
+}
+
+pboolean
+p_tree_rb_remove (PTreeBaseNode **root_node,
+ PCompareDataFunc compare_func,
+ ppointer data,
+ PDestroyFunc key_destroy_func,
+ PDestroyFunc value_destroy_func,
+ pconstpointer key)
+{
+ PTreeBaseNode *cur_node;
+ PTreeBaseNode *prev_node;
+ PTreeBaseNode *child_node;
+ PTreeRBNode *child_parent;
+ pint cmp_result;
+
+ cur_node = *root_node;
+
+ while (cur_node != NULL) {
+ cmp_result = compare_func (key, cur_node->key, data);
+
+ if (cmp_result < 0)
+ cur_node = cur_node->left;
+ else if (cmp_result > 0)
+ cur_node = cur_node->right;
+ else
+ break;
+ }
+
+ if (P_UNLIKELY (cur_node == NULL))
+ return FALSE;
+
+ if (cur_node->left != NULL && cur_node->right != NULL) {
+ prev_node = cur_node->left;
+
+ while (prev_node->right != NULL)
+ prev_node = prev_node->right;
+
+ cur_node->key = prev_node->key;
+ cur_node->value = prev_node->value;
+
+ /* Mark node for removal */
+ cur_node = prev_node;
+ }
+
+ child_node = cur_node->left == NULL ? cur_node->right : cur_node->left;
+
+ if (child_node == NULL && pp_tree_rb_is_black ((PTreeRBNode *) cur_node) == TRUE)
+ pp_tree_rb_balance_remove ((PTreeRBNode *) cur_node, root_node);
+
+ /* Replace node with its child */
+ if (cur_node == *root_node) {
+ *root_node = child_node;
+ child_parent = NULL;
+ } else {
+ child_parent = ((PTreeRBNode *) cur_node)->parent;
+
+ if (child_parent->base.left == cur_node)
+ child_parent->base.left = child_node;
+ else
+ child_parent->base.right = child_node;
+ }
+
+ if (child_node != NULL) {
+ ((PTreeRBNode *) child_node)->parent = child_parent;
+
+ /* Check if we need to repaint the node */
+ if (pp_tree_rb_is_black ((PTreeRBNode *) cur_node) == TRUE)
+ ((PTreeRBNode *) child_node)->color = P_TREE_RB_COLOR_BLACK;
+ }
+
+ /* Free unused node */
+ if (key_destroy_func != NULL)
+ key_destroy_func (cur_node->key);
+
+ if (value_destroy_func != NULL)
+ value_destroy_func (cur_node->value);
+
+ p_free (cur_node);
+
+ return TRUE;
+}
+
+void
+p_tree_rb_node_free (PTreeBaseNode *node)
+{
+ p_free (node);
+}
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