1 /************************************************************************** 2 * 3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28 /** 29 * @file 30 * Hash table implementation. 31 * 32 * This file provides a hash implementation that is capable of dealing 33 * with collisions. It stores colliding entries in linked list. All 34 * functions operating on the hash return an iterator. The iterator 35 * itself points to the collision list. If there wasn't any collision 36 * the list will have just one entry, otherwise client code should 37 * iterate over the entries to find the exact entry among ones that 38 * had the same key (e.g. memcmp could be used on the data to check 39 * that) 40 * 41 * @author Zack Rusin <zack (at) tungstengraphics.com> 42 */ 43 44 #ifndef CSO_HASH_H 45 #define CSO_HASH_H 46 47 #include "pipe/p_compiler.h" 48 49 #ifdef __cplusplus 50 extern "C" { 51 #endif 52 53 54 struct cso_hash; 55 struct cso_node; 56 57 58 struct cso_hash_iter { 59 struct cso_hash *hash; 60 struct cso_node *node; 61 }; 62 63 64 struct cso_hash *cso_hash_create(void); 65 void cso_hash_delete(struct cso_hash *hash); 66 67 68 int cso_hash_size(struct cso_hash *hash); 69 70 71 /** 72 * Adds a data with the given key to the hash. If entry with the given 73 * key is already in the hash, this current entry is instered before it 74 * in the collision list. 75 * Function returns iterator pointing to the inserted item in the hash. 76 */ 77 struct cso_hash_iter cso_hash_insert(struct cso_hash *hash, unsigned key, 78 void *data); 79 /** 80 * Removes the item pointed to by the current iterator from the hash. 81 * Note that the data itself is not erased and if it was a malloc'ed pointer 82 * it will have to be freed after calling this function by the callee. 83 * Function returns iterator pointing to the item after the removed one in 84 * the hash. 85 */ 86 struct cso_hash_iter cso_hash_erase(struct cso_hash *hash, struct cso_hash_iter iter); 87 88 void *cso_hash_take(struct cso_hash *hash, unsigned key); 89 90 91 92 struct cso_hash_iter cso_hash_first_node(struct cso_hash *hash); 93 94 /** 95 * Return an iterator pointing to the first entry in the collision list. 96 */ 97 struct cso_hash_iter cso_hash_find(struct cso_hash *hash, unsigned key); 98 99 /** 100 * Returns true if a value with the given key exists in the hash 101 */ 102 boolean cso_hash_contains(struct cso_hash *hash, unsigned key); 103 104 105 int cso_hash_iter_is_null(struct cso_hash_iter iter); 106 unsigned cso_hash_iter_key(struct cso_hash_iter iter); 107 void *cso_hash_iter_data(struct cso_hash_iter iter); 108 109 110 struct cso_hash_iter cso_hash_iter_next(struct cso_hash_iter iter); 111 struct cso_hash_iter cso_hash_iter_prev(struct cso_hash_iter iter); 112 113 114 /** 115 * Convenience routine to iterate over the collision list while doing a memory 116 * comparison to see which entry in the list is a direct copy of our template 117 * and returns that entry. 118 */ 119 void *cso_hash_find_data_from_template( struct cso_hash *hash, 120 unsigned hash_key, 121 void *templ, 122 int size ); 123 124 125 #ifdef __cplusplus 126 } 127 #endif 128 129 #endif 130
