/************************************************************************** * * Copyright 2007 VMware, Inc. * All Rights Reserved. * * 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, sub license, 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 (including the * next paragraph) 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 NON-INFRINGEMENT. * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS 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. * **************************************************************************/ /** * @file * Hash implementation. * * This file provides a hash implementation that is capable of dealing * with collisions. It stores colliding entries in linked list. All * functions operating on the hash return an iterator. The iterator * itself points to the collision list. If there wasn't any collision * the list will have just one entry, otherwise client code should * iterate over the entries to find the exact entry among ones that * had the same key (e.g. memcmp could be used on the data to check * that) * * @author Zack Rusin */ #ifndef UTIL_HASH_H #define UTIL_HASH_H #include struct util_hash; struct util_node; struct util_hash_iter { struct util_hash *hash; struct util_node *node; }; struct util_hash *util_hash_create(void); void util_hash_delete(struct util_hash *hash); /** * Adds a data with the given key to the hash. If entry with the given * key is already in the hash, this current entry is instered before it * in the collision list. * Function returns iterator pointing to the inserted item in the hash. */ struct util_hash_iter util_hash_insert(struct util_hash *hash, unsigned key, void *data); /** * Removes the item pointed to by the current iterator from the hash. * Note that the data itself is not erased and if it was a malloc'ed pointer * it will have to be freed after calling this function by the callee. * Function returns iterator pointing to the item after the removed one in * the hash. */ struct util_hash_iter util_hash_erase(struct util_hash *hash, struct util_hash_iter iter); void *util_hash_take(struct util_hash *hash, unsigned key); struct util_hash_iter util_hash_first_node(struct util_hash *hash); /** * Return an iterator pointing to the first entry in the collision list. */ struct util_hash_iter util_hash_find(struct util_hash *hash, unsigned key); int util_hash_iter_is_null(struct util_hash_iter iter); unsigned util_hash_iter_key(struct util_hash_iter iter); void *util_hash_iter_data(struct util_hash_iter iter); struct util_hash_iter util_hash_iter_next(struct util_hash_iter iter); #endif