ucx/avl.c

Fri, 26 Feb 2016 16:00:18 +0100

author
Mike Becker <universe@uap-core.de>
date
Fri, 26 Feb 2016 16:00:18 +0100
changeset 216
dee5a88c4db7
parent 205
54a7ceb9151f
child 225
a1a068c2c4ef
permissions
-rw-r--r--

added casts for mallocs in AVL implementation (to satisfy c++ compiler)

universe@192 1 /*
universe@192 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@192 3 *
universe@192 4 * Copyright 2015 Olaf Wintermann. All rights reserved.
universe@192 5 *
universe@192 6 * Redistribution and use in source and binary forms, with or without
universe@192 7 * modification, are permitted provided that the following conditions are met:
universe@192 8 *
universe@192 9 * 1. Redistributions of source code must retain the above copyright
universe@192 10 * notice, this list of conditions and the following disclaimer.
universe@192 11 *
universe@192 12 * 2. Redistributions in binary form must reproduce the above copyright
universe@192 13 * notice, this list of conditions and the following disclaimer in the
universe@192 14 * documentation and/or other materials provided with the distribution.
universe@192 15 *
universe@192 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@192 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@192 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@192 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@192 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@192 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@192 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@192 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@192 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@192 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@192 26 * POSSIBILITY OF SUCH DAMAGE.
universe@192 27 */
universe@192 28
universe@192 29 #include "avl.h"
universe@192 30
universe@195 31 #define ptrcast(ptr) ((void*)(ptr))
universe@216 32 #define alloc_tree(al) (UcxAVLTree*) almalloc((al), sizeof(UcxAVLTree))
universe@216 33 #define alloc_node(al) (UcxAVLNode*) almalloc((al), sizeof(UcxAVLNode))
universe@195 34
universe@195 35 static void ucx_avl_connect(UcxAVLTree *tree,
universe@195 36 UcxAVLNode *node, UcxAVLNode *child, intptr_t nullkey) {
universe@195 37 if (child) {
universe@195 38 child->parent = node;
universe@195 39 }
universe@195 40 // if child is NULL, nullkey decides if left or right pointer is cleared
universe@195 41 if (tree->cmpfunc(
universe@195 42 ptrcast(child ? child->key : nullkey),
universe@195 43 ptrcast(node->key), tree->userdata) > 0) {
universe@195 44 node->right = child;
universe@195 45 } else {
universe@195 46 node->left = child;
universe@195 47 }
universe@195 48 size_t lh = node->left ? node->left->height : 0;
universe@195 49 size_t rh = node->right ? node->right->height : 0;
universe@195 50 node->height = 1 + (lh > rh ? lh : rh);
universe@195 51 }
universe@195 52
universe@195 53 #define avlheight(node) ((node) ? (node)->height : 0)
universe@195 54
universe@195 55 static UcxAVLNode* avl_rotright(UcxAVLTree *tree, UcxAVLNode *l0) {
universe@195 56 UcxAVLNode *p = l0->parent;
universe@195 57 UcxAVLNode *l1 = l0->left;
universe@195 58 if (p) {
universe@195 59 ucx_avl_connect(tree, p, l1, 0);
universe@195 60 } else {
universe@195 61 l1->parent = NULL;
universe@195 62 }
universe@195 63 ucx_avl_connect(tree, l0, l1->right, l1->key);
universe@195 64 ucx_avl_connect(tree, l1, l0, 0);
universe@195 65 return l1;
universe@195 66 }
universe@195 67
universe@195 68 static UcxAVLNode* avl_rotleft(UcxAVLTree *tree, UcxAVLNode *l0) {
universe@195 69 UcxAVLNode *p = l0->parent;
universe@195 70 UcxAVLNode *l1 = l0->right;
universe@195 71 if (p) {
universe@195 72 ucx_avl_connect(tree, p, l1, 0);
universe@195 73 } else {
universe@195 74 l1->parent = NULL;
universe@195 75 }
universe@195 76 ucx_avl_connect(tree, l0, l1->left, l1->key);
universe@195 77 ucx_avl_connect(tree, l1, l0, 0);
universe@195 78 return l1;
universe@195 79 }
universe@195 80
universe@195 81 static void ucx_avl_balance(UcxAVLTree *tree, UcxAVLNode *n) {
universe@195 82 int lh = avlheight(n->left);
universe@195 83 int rh = avlheight(n->right);
universe@195 84 n->height = 1 + (lh > rh ? lh : rh);
universe@195 85
universe@195 86 if (lh - rh == 2) {
universe@195 87 UcxAVLNode *c = n->left;
universe@195 88 if (avlheight(c->right) - avlheight(c->left) == 1) {
universe@195 89 avl_rotleft(tree, c);
universe@195 90 }
universe@195 91 n = avl_rotright(tree, n);
universe@195 92 } else if (rh - lh == 2) {
universe@195 93 UcxAVLNode *c = n->right;
universe@195 94 if (avlheight(c->left) - avlheight(c->right) == 1) {
universe@195 95 avl_rotright(tree, c);
universe@195 96 }
universe@195 97 n = avl_rotleft(tree, n);
universe@195 98 }
universe@195 99
universe@195 100 if (n->parent) {
universe@195 101 ucx_avl_balance(tree, n->parent);
universe@195 102 } else {
universe@195 103 tree->root = n;
universe@195 104 }
universe@195 105 }
universe@195 106
universe@194 107 UcxAVLTree *ucx_avl_new(cmp_func cmpfunc) {
universe@194 108 return ucx_avl_new_a(cmpfunc, ucx_default_allocator());
universe@194 109 }
universe@194 110
universe@194 111 UcxAVLTree *ucx_avl_new_a(cmp_func cmpfunc, UcxAllocator *allocator) {
universe@216 112 UcxAVLTree* tree = alloc_tree(allocator);
universe@194 113 if (tree) {
universe@194 114 tree->allocator = allocator;
universe@194 115 tree->cmpfunc = cmpfunc;
universe@194 116 tree->root = NULL;
universe@194 117 tree->userdata = NULL;
universe@194 118 }
universe@194 119
universe@194 120 return tree;
universe@194 121 }
universe@194 122
universe@196 123 static void ucx_avl_free_node(UcxAllocator *al, UcxAVLNode *node) {
universe@196 124 if (node) {
universe@196 125 ucx_avl_free_node(al, node->left);
universe@196 126 ucx_avl_free_node(al, node->right);
universe@196 127 alfree(al, node);
universe@196 128 }
universe@196 129 }
universe@196 130
universe@196 131 void ucx_avl_free(UcxAVLTree *tree) {
universe@196 132 UcxAllocator *al = tree->allocator;
universe@196 133 ucx_avl_free_node(al, tree->root);
universe@196 134 alfree(al, tree);
universe@196 135 }
universe@196 136
universe@205 137 UcxAVLNode *ucx_avl_get_node(UcxAVLTree *tree, intptr_t key) {
universe@195 138 UcxAVLNode *n = tree->root;
universe@195 139 int cmpresult;
universe@195 140 while (n && (cmpresult = tree->cmpfunc(
universe@195 141 ptrcast(key), ptrcast(n->key), tree->userdata))) {
universe@195 142 n = cmpresult > 0 ? n->right : n->left;
universe@195 143 }
universe@204 144 return n;
universe@204 145 }
universe@204 146
universe@204 147 void *ucx_avl_get(UcxAVLTree *tree, intptr_t key) {
universe@205 148 UcxAVLNode *n = ucx_avl_get_node(tree, key);
universe@195 149 return n ? n->value : NULL;
universe@194 150 }
universe@194 151
universe@204 152 int ucx_avl_put(UcxAVLTree *tree, intptr_t key, void *value) {
universe@204 153 return ucx_avl_put_s(tree, key, value, NULL);
universe@204 154 }
universe@204 155
universe@204 156 int ucx_avl_put_s(UcxAVLTree *tree, intptr_t key, void *value,
universe@204 157 void **oldvalue) {
universe@195 158 if (tree->root) {
universe@195 159 UcxAVLNode *n = tree->root;
universe@195 160 int cmpresult;
universe@197 161 while ((cmpresult = tree->cmpfunc(
universe@197 162 ptrcast(key), ptrcast(n->key), tree->userdata))) {
universe@195 163 UcxAVLNode *m = cmpresult > 0 ? n->right : n->left;
universe@195 164 if (m) {
universe@195 165 n = m;
universe@195 166 } else {
universe@195 167 break;
universe@195 168 }
universe@195 169 }
universe@195 170
universe@195 171 if (cmpresult) {
universe@216 172 UcxAVLNode* e = alloc_node(tree->allocator);
universe@204 173 if (e) {
universe@204 174 e->key = key; e->value = value; e->height = 1;
universe@204 175 e->parent = e->left = e->right = NULL;
universe@204 176 ucx_avl_connect(tree, n, e, 0);
universe@204 177 ucx_avl_balance(tree, n);
universe@204 178 return 0;
universe@204 179 } else {
universe@204 180 return 1;
universe@204 181 }
universe@195 182 } else {
universe@204 183 if (oldvalue) {
universe@204 184 *oldvalue = n->value;
universe@204 185 }
universe@195 186 n->value = value;
universe@204 187 return 0;
universe@195 188 }
universe@195 189 } else {
universe@216 190 tree->root = alloc_node(tree->allocator);
universe@204 191 if (tree->root) {
universe@204 192 tree->root->key = key; tree->root->value = value;
universe@204 193 tree->root->height = 1;
universe@204 194 tree->root->parent = tree->root->left = tree->root->right = NULL;
universe@204 195
universe@204 196 if (oldvalue) {
universe@204 197 *oldvalue = NULL;
universe@204 198 }
universe@204 199
universe@204 200 return 0;
universe@204 201 } else {
universe@204 202 return 1;
universe@204 203 }
universe@195 204 }
universe@194 205 }
universe@194 206
universe@204 207 int ucx_avl_remove(UcxAVLTree *tree, intptr_t key) {
universe@204 208 return ucx_avl_remove_s(tree, key, NULL, NULL);
universe@204 209 }
universe@204 210
universe@205 211 int ucx_avl_remove_node(UcxAVLTree *tree, UcxAVLNode *node) {
universe@204 212 return ucx_avl_remove_s(tree, node->key, NULL, NULL);
universe@204 213 }
universe@204 214
universe@204 215 int ucx_avl_remove_s(UcxAVLTree *tree, intptr_t key,
universe@204 216 intptr_t *oldkey, void **oldvalue) {
universe@204 217
universe@195 218 UcxAVLNode *n = tree->root;
universe@195 219 int cmpresult;
universe@195 220 while (n && (cmpresult = tree->cmpfunc(
universe@195 221 ptrcast(key), ptrcast(n->key), tree->userdata))) {
universe@195 222 n = cmpresult > 0 ? n->right : n->left;
universe@195 223 }
universe@195 224 if (n) {
universe@204 225 if (oldkey) {
universe@204 226 *oldkey = n->key;
universe@204 227 }
universe@204 228 if (oldvalue) {
universe@204 229 *oldvalue = n->value;
universe@204 230 }
universe@204 231
universe@195 232 UcxAVLNode *p = n->parent;
universe@195 233 if (n->left && n->right) {
universe@195 234 UcxAVLNode *s = n->right;
universe@195 235 while (s->left) {
universe@195 236 s = s->left;
universe@195 237 }
universe@195 238 ucx_avl_connect(tree, s->parent, s->right, s->key);
universe@195 239 n->key = s->key; n->value = s->value;
universe@195 240 p = s->parent;
universe@196 241 alfree(tree->allocator, s);
universe@195 242 } else {
universe@195 243 if (p) {
universe@195 244 ucx_avl_connect(tree, p, n->right ? n->right:n->left, n->key);
universe@195 245 } else {
universe@195 246 tree->root = n->right ? n->right : n->left;
olaf@203 247 if (tree->root) {
olaf@202 248 tree->root->parent = NULL;
olaf@202 249 }
universe@195 250 }
universe@196 251 alfree(tree->allocator, n);
universe@195 252 }
universe@195 253
universe@195 254 if (p) {
universe@195 255 ucx_avl_balance(tree, p);
universe@195 256 }
universe@204 257
universe@204 258 return 0;
universe@195 259 } else {
universe@204 260 return 1;
universe@195 261 }
universe@194 262 }
universe@194 263
universe@199 264 static size_t ucx_avl_countn(UcxAVLNode *node) {
universe@199 265 if (node) {
universe@199 266 return 1 + ucx_avl_countn(node->left) + ucx_avl_countn(node->right);
universe@199 267 } else {
universe@199 268 return 0;
universe@199 269 }
universe@199 270 }
universe@199 271
universe@199 272 size_t ucx_avl_count(UcxAVLTree *tree) {
universe@199 273 return ucx_avl_countn(tree->root);
universe@199 274 }

mercurial