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-rw-r--r--src/zix/tree.c727
1 files changed, 0 insertions, 727 deletions
diff --git a/src/zix/tree.c b/src/zix/tree.c
deleted file mode 100644
index 9faf13c..0000000
--- a/src/zix/tree.c
+++ /dev/null
@@ -1,727 +0,0 @@
-/*
- Copyright 2011-2020 David Robillard <d@drobilla.net>
-
- Permission to use, copy, modify, and/or distribute this software for any
- purpose with or without fee is hereby granted, provided that the above
- copyright notice and this permission notice appear in all copies.
-
- THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-
-#include "zix/tree.h"
-
-#include "zix/common.h"
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
-typedef struct ZixTreeNodeImpl ZixTreeNode;
-
-struct ZixTreeImpl {
- ZixTreeNode* root;
- ZixDestroyFunc destroy;
- ZixComparator cmp;
- void* cmp_data;
- size_t size;
- bool allow_duplicates;
-};
-
-struct ZixTreeNodeImpl {
- void* data;
- struct ZixTreeNodeImpl* left;
- struct ZixTreeNodeImpl* right;
- struct ZixTreeNodeImpl* parent;
- int balance;
-};
-
-#define MIN(a, b) (((a) < (b)) ? (a) : (b))
-#define MAX(a, b) (((a) > (b)) ? (a) : (b))
-
-// Uncomment these for debugging features
-// #define ZIX_TREE_DUMP 1
-// #define ZIX_TREE_VERIFY 1
-// #define ZIX_TREE_HYPER_VERIFY 1
-
-#if defined(ZIX_TREE_VERIFY) || defined(ZIX_TREE_HYPER_VERIFY)
-# include "tree_debug.h"
-# define ASSERT_BALANCE(n) assert(verify_balance(n))
-#else
-# define ASSERT_BALANCE(n)
-#endif
-
-#ifdef ZIX_TREE_DUMP
-# include "tree_debug.h"
-# define DUMP(t) zix_tree_print(t->root, 0)
-# define DEBUG_PRINTF(fmt, ...) printf(fmt, __VA_ARGS__)
-#else
-# define DUMP(t)
-# define DEBUG_PRINTF(fmt, ...)
-#endif
-
-ZixTree*
-zix_tree_new(bool allow_duplicates,
- ZixComparator cmp,
- void* cmp_data,
- ZixDestroyFunc destroy)
-{
- ZixTree* t = (ZixTree*)malloc(sizeof(ZixTree));
- t->root = NULL;
- t->destroy = destroy;
- t->cmp = cmp;
- t->cmp_data = cmp_data;
- t->size = 0;
- t->allow_duplicates = allow_duplicates;
- return t;
-}
-
-static void
-zix_tree_free_rec(ZixTree* t, ZixTreeNode* n)
-{
- if (n) {
- zix_tree_free_rec(t, n->left);
- zix_tree_free_rec(t, n->right);
- if (t->destroy) {
- t->destroy(n->data);
- }
- free(n);
- }
-}
-
-void
-zix_tree_free(ZixTree* t)
-{
- if (t) {
- zix_tree_free_rec(t, t->root);
- free(t);
- }
-}
-
-size_t
-zix_tree_size(const ZixTree* t)
-{
- return t->size;
-}
-
-static void
-rotate(ZixTreeNode* p, ZixTreeNode* q)
-{
- assert(q->parent == p);
- assert(p->left == q || p->right == q);
-
- q->parent = p->parent;
- if (q->parent) {
- if (q->parent->left == p) {
- q->parent->left = q;
- } else {
- q->parent->right = q;
- }
- }
-
- if (p->right == q) {
- // Rotate left
- p->right = q->left;
- q->left = p;
- if (p->right) {
- p->right->parent = p;
- }
- } else {
- // Rotate right
- assert(p->left == q);
- p->left = q->right;
- q->right = p;
- if (p->left) {
- p->left->parent = p;
- }
- }
-
- p->parent = q;
-}
-
-/**
- * Rotate left about `p`.
- *
- * p q
- * / \ / \
- * A q => p C
- * / \ / \
- * B C A B
- */
-static ZixTreeNode*
-rotate_left(ZixTreeNode* p, int* height_change)
-{
- ZixTreeNode* const q = p->right;
- *height_change = (q->balance == 0) ? 0 : -1;
-
- DEBUG_PRINTF("LL %ld\n", (intptr_t)p->data);
-
- assert(p->balance == 2);
- assert(q->balance == 0 || q->balance == 1);
-
- rotate(p, q);
-
- // p->balance -= 1 + MAX(0, q->balance);
- // q->balance -= 1 - MIN(0, p->balance);
- --q->balance;
- p->balance = -(q->balance);
-
- ASSERT_BALANCE(p);
- ASSERT_BALANCE(q);
- return q;
-}
-
-/**
- * Rotate right about `p`.
- *
- * p q
- * / \ / \
- * q C => A p
- * / \ / \
- * A B B C
- *
- */
-static ZixTreeNode*
-rotate_right(ZixTreeNode* p, int* height_change)
-{
- ZixTreeNode* const q = p->left;
- *height_change = (q->balance == 0) ? 0 : -1;
-
- DEBUG_PRINTF("RR %ld\n", (intptr_t)p->data);
-
- assert(p->balance == -2);
- assert(q->balance == 0 || q->balance == -1);
-
- rotate(p, q);
-
- // p->balance += 1 - MIN(0, q->balance);
- // q->balance += 1 + MAX(0, p->balance);
- ++q->balance;
- p->balance = -(q->balance);
-
- ASSERT_BALANCE(p);
- ASSERT_BALANCE(q);
- return q;
-}
-
-/**
- * Rotate left about `p->left` then right about `p`.
- *
- * p r
- * / \ / \
- * q D => q p
- * / \ / \ / \
- * A r A B C D
- * / \
- * B C
- *
- */
-static ZixTreeNode*
-rotate_left_right(ZixTreeNode* p, int* height_change)
-{
- ZixTreeNode* const q = p->left;
- ZixTreeNode* const r = q->right;
-
- assert(p->balance == -2);
- assert(q->balance == 1);
- assert(r->balance == -1 || r->balance == 0 || r->balance == 1);
-
- DEBUG_PRINTF("LR %ld P: %2d Q: %2d R: %2d\n",
- (intptr_t)p->data,
- p->balance,
- q->balance,
- r->balance);
-
- rotate(q, r);
- rotate(p, r);
-
- q->balance -= 1 + MAX(0, r->balance);
- p->balance += 1 - MIN(MIN(0, r->balance) - 1, r->balance + q->balance);
- // r->balance += MAX(0, p->balance) + MIN(0, q->balance);
-
- // p->balance = (p->left && p->right) ? -MIN(r->balance, 0) : 0;
- // q->balance = - MAX(r->balance, 0);
- r->balance = 0;
-
- *height_change = -1;
-
- ASSERT_BALANCE(p);
- ASSERT_BALANCE(q);
- ASSERT_BALANCE(r);
- return r;
-}
-
-/**
- * Rotate right about `p->right` then right about `p`.
- *
- * p r
- * / \ / \
- * A q => p q
- * / \ / \ / \
- * r D A B C D
- * / \
- * B C
- *
- */
-static ZixTreeNode*
-rotate_right_left(ZixTreeNode* p, int* height_change)
-{
- ZixTreeNode* const q = p->right;
- ZixTreeNode* const r = q->left;
-
- assert(p->balance == 2);
- assert(q->balance == -1);
- assert(r->balance == -1 || r->balance == 0 || r->balance == 1);
-
- DEBUG_PRINTF("RL %ld P: %2d Q: %2d R: %2d\n",
- (intptr_t)p->data,
- p->balance,
- q->balance,
- r->balance);
-
- rotate(q, r);
- rotate(p, r);
-
- q->balance += 1 - MIN(0, r->balance);
- p->balance -= 1 + MAX(MAX(0, r->balance) + 1, r->balance + q->balance);
- // r->balance += MAX(0, q->balance) + MIN(0, p->balance);
-
- // p->balance = (p->left && p->right) ? -MAX(r->balance, 0) : 0;
- // q->balance = - MIN(r->balance, 0);
- r->balance = 0;
- // assert(r->balance == 0);
-
- *height_change = -1;
-
- ASSERT_BALANCE(p);
- ASSERT_BALANCE(q);
- ASSERT_BALANCE(r);
- return r;
-}
-
-static ZixTreeNode*
-zix_tree_rebalance(ZixTree* t, ZixTreeNode* node, int* height_change)
-{
-#ifdef ZIX_TREE_HYPER_VERIFY
- const size_t old_height = height(node);
-#endif
- DEBUG_PRINTF("REBALANCE %ld (%d)\n", (intptr_t)node->data, node->balance);
- *height_change = 0;
- const bool is_root = !node->parent;
- assert((is_root && t->root == node) || (!is_root && t->root != node));
- ZixTreeNode* replacement = node;
- if (node->balance == -2) {
- assert(node->left);
- if (node->left->balance == 1) {
- replacement = rotate_left_right(node, height_change);
- } else {
- replacement = rotate_right(node, height_change);
- }
- } else if (node->balance == 2) {
- assert(node->right);
- if (node->right->balance == -1) {
- replacement = rotate_right_left(node, height_change);
- } else {
- replacement = rotate_left(node, height_change);
- }
- }
- if (is_root) {
- assert(!replacement->parent);
- t->root = replacement;
- }
- DUMP(t);
-#ifdef ZIX_TREE_HYPER_VERIFY
- assert(old_height + *height_change == height(replacement));
-#endif
- return replacement;
-}
-
-ZixStatus
-zix_tree_insert(ZixTree* t, void* e, ZixTreeIter** ti)
-{
- DEBUG_PRINTF("**** INSERT %ld\n", (intptr_t)e);
- int cmp = 0;
- ZixTreeNode* n = t->root;
- ZixTreeNode* p = NULL;
-
- // Find the parent p of e
- while (n) {
- p = n;
- cmp = t->cmp(e, n->data, t->cmp_data);
- if (cmp < 0) {
- n = n->left;
- } else if (cmp > 0 || t->allow_duplicates) {
- n = n->right;
- } else {
- if (ti) {
- *ti = n;
- }
- DEBUG_PRINTF("%ld EXISTS!\n", (intptr_t)e);
- return ZIX_STATUS_EXISTS;
- }
- }
-
- // Allocate a new node n
- if (!(n = (ZixTreeNode*)malloc(sizeof(ZixTreeNode)))) {
- return ZIX_STATUS_NO_MEM;
- }
- memset(n, '\0', sizeof(ZixTreeNode));
- n->data = e;
- n->balance = 0;
- if (ti) {
- *ti = n;
- }
-
- bool p_height_increased = false;
-
- // Make p the parent of n
- n->parent = p;
- if (!p) {
- t->root = n;
- } else {
- if (cmp < 0) {
- assert(!p->left);
- assert(p->balance == 0 || p->balance == 1);
- p->left = n;
- --p->balance;
- p_height_increased = !p->right;
- } else {
- assert(!p->right);
- assert(p->balance == 0 || p->balance == -1);
- p->right = n;
- ++p->balance;
- p_height_increased = !p->left;
- }
- }
-
- DUMP(t);
-
- // Rebalance if necessary (at most 1 rotation)
- assert(!p || p->balance == -1 || p->balance == 0 || p->balance == 1);
- if (p && p_height_increased) {
- int height_change = 0;
- for (ZixTreeNode* i = p; i && i->parent; i = i->parent) {
- if (i == i->parent->left) {
- if (--i->parent->balance == -2) {
- zix_tree_rebalance(t, i->parent, &height_change);
- break;
- }
- } else {
- assert(i == i->parent->right);
- if (++i->parent->balance == 2) {
- zix_tree_rebalance(t, i->parent, &height_change);
- break;
- }
- }
-
- if (i->parent->balance == 0) {
- break;
- }
- }
- }
-
- DUMP(t);
-
- ++t->size;
-
-#ifdef ZIX_TREE_VERIFY
- if (!verify(t, t->root)) {
- return ZIX_STATUS_ERROR;
- }
-#endif
-
- return ZIX_STATUS_SUCCESS;
-}
-
-ZixStatus
-zix_tree_remove(ZixTree* t, ZixTreeIter* ti)
-{
- ZixTreeNode* const n = ti;
- ZixTreeNode** pp = NULL; // parent pointer
- ZixTreeNode* to_balance = n->parent; // lowest node to balance
- int d_balance = 0; // delta(balance) for n->parent
-
- DEBUG_PRINTF("*** REMOVE %ld\n", (intptr_t)n->data);
-
- if ((n == t->root) && !n->left && !n->right) {
- t->root = NULL;
- if (t->destroy) {
- t->destroy(n->data);
- }
- free(n);
- --t->size;
- assert(t->size == 0);
- return ZIX_STATUS_SUCCESS;
- }
-
- // Set pp to the parent pointer to n, if applicable
- if (n->parent) {
- assert(n->parent->left == n || n->parent->right == n);
- if (n->parent->left == n) { // n is left child
- pp = &n->parent->left;
- d_balance = 1;
- } else { // n is right child
- assert(n->parent->right == n);
- pp = &n->parent->right;
- d_balance = -1;
- }
- }
-
- assert(!pp || *pp == n);
-
- int height_change = 0;
- if (!n->left && !n->right) {
- // n is a leaf, just remove it
- if (pp) {
- *pp = NULL;
- to_balance = n->parent;
- height_change = (!n->parent->left && !n->parent->right) ? -1 : 0;
- }
-
- } else if (!n->left) {
- // Replace n with right (only) child
- if (pp) {
- *pp = n->right;
- to_balance = n->parent;
- } else {
- t->root = n->right;
- }
- n->right->parent = n->parent;
- height_change = -1;
-
- } else if (!n->right) {
- // Replace n with left (only) child
- if (pp) {
- *pp = n->left;
- to_balance = n->parent;
- } else {
- t->root = n->left;
- }
- n->left->parent = n->parent;
- height_change = -1;
-
- } else {
- // Replace n with in-order successor (leftmost child of right subtree)
- ZixTreeNode* replace = n->right;
- while (replace->left) {
- assert(replace->left->parent == replace);
- replace = replace->left;
- }
-
- // Remove replace from parent (replace_p)
- if (replace->parent->left == replace) {
- height_change = replace->parent->right ? 0 : -1;
- d_balance = 1;
- to_balance = replace->parent;
- replace->parent->left = replace->right;
- } else {
- assert(replace->parent == n);
- height_change = replace->parent->left ? 0 : -1;
- d_balance = -1;
- to_balance = replace->parent;
- replace->parent->right = replace->right;
- }
-
- if (to_balance == n) {
- to_balance = replace;
- }
-
- if (replace->right) {
- replace->right->parent = replace->parent;
- }
-
- replace->balance = n->balance;
-
- // Swap node to delete with replace
- if (pp) {
- *pp = replace;
- } else {
- assert(t->root == n);
- t->root = replace;
- }
-
- replace->parent = n->parent;
- replace->left = n->left;
- n->left->parent = replace;
- replace->right = n->right;
- if (n->right) {
- n->right->parent = replace;
- }
-
- assert(!replace->parent || replace->parent->left == replace ||
- replace->parent->right == replace);
- }
-
- // Rebalance starting at to_balance upwards.
- for (ZixTreeNode* i = to_balance; i; i = i->parent) {
- i->balance += d_balance;
- if (d_balance == 0 || i->balance == -1 || i->balance == 1) {
- break;
- }
-
- assert(i != n);
- i = zix_tree_rebalance(t, i, &height_change);
- if (i->balance == 0) {
- height_change = -1;
- }
-
- if (i->parent) {
- if (i == i->parent->left) {
- d_balance = height_change * -1;
- } else {
- assert(i == i->parent->right);
- d_balance = height_change;
- }
- }
- }
-
- DUMP(t);
-
- if (t->destroy) {
- t->destroy(n->data);
- }
- free(n);
-
- --t->size;
-
-#ifdef ZIX_TREE_VERIFY
- if (!verify(t, t->root)) {
- return ZIX_STATUS_ERROR;
- }
-#endif
-
- return ZIX_STATUS_SUCCESS;
-}
-
-ZixStatus
-zix_tree_find(const ZixTree* t, const void* e, ZixTreeIter** ti)
-{
- ZixTreeNode* n = t->root;
- while (n) {
- const int cmp = t->cmp(e, n->data, t->cmp_data);
- if (cmp == 0) {
- break;
- }
-
- if (cmp < 0) {
- n = n->left;
- } else {
- n = n->right;
- }
- }
-
- *ti = n;
- return (n) ? ZIX_STATUS_SUCCESS : ZIX_STATUS_NOT_FOUND;
-}
-
-void*
-zix_tree_get(const ZixTreeIter* ti)
-{
- return ti ? ti->data : NULL;
-}
-
-ZixTreeIter*
-zix_tree_begin(ZixTree* t)
-{
- if (!t->root) {
- return NULL;
- }
-
- ZixTreeNode* n = t->root;
- while (n->left) {
- n = n->left;
- }
-
- return n;
-}
-
-ZixTreeIter*
-zix_tree_end(ZixTree* ZIX_UNUSED(t))
-{
- return NULL;
-}
-
-ZixTreeIter*
-zix_tree_rbegin(ZixTree* t)
-{
- if (!t->root) {
- return NULL;
- }
-
- ZixTreeNode* n = t->root;
- while (n->right) {
- n = n->right;
- }
-
- return n;
-}
-
-ZixTreeIter*
-zix_tree_rend(ZixTree* ZIX_UNUSED(t))
-{
- return NULL;
-}
-
-bool
-zix_tree_iter_is_end(const ZixTreeIter* i)
-{
- return !i;
-}
-
-bool
-zix_tree_iter_is_rend(const ZixTreeIter* i)
-{
- return !i;
-}
-
-ZixTreeIter*
-zix_tree_iter_next(ZixTreeIter* i)
-{
- if (!i) {
- return NULL;
- }
-
- if (i->right) {
- i = i->right;
- while (i->left) {
- i = i->left;
- }
- } else {
- while (i->parent && i->parent->right == i) { // i is a right child
- i = i->parent;
- }
-
- i = i->parent;
- }
-
- return i;
-}
-
-ZixTreeIter*
-zix_tree_iter_prev(ZixTreeIter* i)
-{
- if (!i) {
- return NULL;
- }
-
- if (i->left) {
- i = i->left;
- while (i->right) {
- i = i->right;
- }
-
- } else {
- while (i->parent && i->parent->left == i) { // i is a left child
- i = i->parent;
- }
-
- i = i->parent;
- }
-
- return i;
-}
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