/* Copyright (c) 2002, 2004, Christopher Clark All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the original author; nor the names of any contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* Modifications made by Lei Xia */ #ifndef __VNET_HASHTABLE_H__ #define __VNET_HASHTABLE_H__ #include struct hashtable; /* Example of use: * * struct hashtable *h; * struct some_key *k; * struct some_value *v; * * static uint_t hash_from_key_fn( void *k ); * static int keys_equal_fn ( void *key1, void *key2 ); * * h = create_hashtable(16, hash_from_key_fn, keys_equal_fn); * k = (struct some_key *) malloc(sizeof(struct some_key)); * v = (struct some_value *) malloc(sizeof(struct some_value)); * * (initialise k and v to suitable values) * * if (! hashtable_insert(h,k,v) ) * { exit(-1); } * * if (NULL == (found = hashtable_search(h,k) )) * { printf("not found!"); } * * if (NULL == (found = hashtable_remove(h,k) )) * { printf("Not found\n"); } * */ /* Macros may be used to define type-safe(r) hashtable access functions, with * methods specialized to take known key and value types as parameters. * * Example: * * Insert this at the start of your file: * * DEFINE_HASHTABLE_INSERT(insert_some, struct some_key, struct some_value); * DEFINE_HASHTABLE_SEARCH(search_some, struct some_key, struct some_value); * DEFINE_HASHTABLE_REMOVE(remove_some, struct some_key, struct some_value); * * This defines the functions 'insert_some', 'search_some' and 'remove_some'. * These operate just like hashtable_insert etc., with the same parameters, * but their function signatures have 'struct some_key *' rather than * 'void *', and hence can generate compile time errors if your program is * supplying incorrect data as a key (and similarly for value). * * Note that the hash and key equality functions passed to create_hashtable * still take 'void *' parameters instead of 'some key *'. This shouldn't be * a difficult issue as they're only defined and passed once, and the other * functions will ensure that only valid keys are supplied to them. * * The cost for this checking is increased code size and runtime overhead * - if performance is important, it may be worth switching back to the * unsafe methods once your program has been debugged with the safe methods. * This just requires switching to some simple alternative defines - eg: * #define insert_some hashtable_insert * */ /* These cannot be inlined because they are referenced as fn ptrs */ unsigned long vnet_hash_long(unsigned long val, unsigned int bits); unsigned long vnet_hash_buffer(unsigned char * msg, unsigned int length); struct hashtable * vnet_create_htable(unsigned int min_size, unsigned int (*hashfunction) (addr_t key), int (*key_eq_fn) (addr_t key1, addr_t key2)); void vnet_free_htable(struct hashtable * htable, int free_values, int free_keys); /* * returns non-zero for successful insertion * * This function will cause the table to expand if the insertion would take * the ratio of entries to table size over the maximum load factor. * * This function does not check for repeated insertions with a duplicate key. * The value returned when using a duplicate key is undefined -- when * the hashtable changes size, the order of retrieval of duplicate key * entries is reversed. * If in doubt, remove before insert. */ int vnet_htable_insert(struct hashtable * htable, addr_t key, addr_t value); // returns the value associated with the key, or NULL if none found addr_t vnet_htable_search(struct hashtable * htable, addr_t key); // returns the value associated with the key, or NULL if none found addr_t vnet_htable_remove(struct hashtable * htable, addr_t key, int free_key); unsigned int vnet_htable_count(struct hashtable * htable); #endif /* * Copyright (c) 2002, Christopher Clark * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * * Neither the name of the original author; nor the names of any contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */