1 /************************************************************************** 2 * 3 * Copyright 2007 VMware, Inc. 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 VMWARE 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 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 <zackr (at) vmware.com> 42 */ 43 44 #ifndef UTIL_HASH_H 45 #define UTIL_HASH_H 46 47 #include <stdbool.h> 48 49 #include "libdrm_macros.h" 50 51 struct util_hash; 52 struct util_node; 53 54 struct util_hash_iter { 55 struct util_hash *hash; 56 struct util_node *node; 57 }; 58 59 60 drm_private struct util_hash *util_hash_create(void); 61 drm_private void util_hash_delete(struct util_hash *hash); 62 63 64 /** 65 * Adds a data with the given key to the hash. If entry with the given 66 * key is already in the hash, this current entry is instered before it 67 * in the collision list. 68 * Function returns iterator pointing to the inserted item in the hash. 69 */ 70 drm_private struct util_hash_iter 71 util_hash_insert(struct util_hash *hash, unsigned key, void *data); 72 73 /** 74 * Removes the item pointed to by the current iterator from the hash. 75 * Note that the data itself is not erased and if it was a malloc'ed pointer 76 * it will have to be freed after calling this function by the callee. 77 * Function returns iterator pointing to the item after the removed one in 78 * the hash. 79 */ 80 drm_private struct util_hash_iter 81 util_hash_erase(struct util_hash *hash, struct util_hash_iter iter); 82 83 drm_private void *util_hash_take(struct util_hash *hash, unsigned key); 84 85 86 drm_private struct util_hash_iter util_hash_first_node(struct util_hash *hash); 87 88 /** 89 * Return an iterator pointing to the first entry in the collision list. 90 */ 91 drm_private struct util_hash_iter 92 util_hash_find(struct util_hash *hash, unsigned key); 93 94 95 drm_private int util_hash_iter_is_null(struct util_hash_iter iter); 96 drm_private unsigned util_hash_iter_key(struct util_hash_iter iter); 97 drm_private void *util_hash_iter_data(struct util_hash_iter iter); 98 99 100 drm_private struct util_hash_iter 101 util_hash_iter_next(struct util_hash_iter iter); 102 103 #endif 104
