unbound/util/storage/lookup3.h
2014-02-07 13:28:39 +00:00

72 lines
2.6 KiB
C

/*
* util/storage/lookup3.h - header file for hashing functions.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 NLNET LABS nor the names of its 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
* HOLDER 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.
*/
/**
* \file
*
* This file contains header definitions for the hash functions we use.
* The hash functions are public domain (see lookup3.c).
*/
#ifndef UTIL_STORAGE_LOOKUP3_H
#define UTIL_STORAGE_LOOKUP3_H
/**
* Hash key made of 4byte chunks.
* @param k: the key, an array of uint32_t values
* @param length: the length of the key, in uint32_ts
* @param initval: the previous hash, or an arbitrary value
* @return: hash value.
*/
uint32_t hashword(const uint32_t *k, size_t length, uint32_t initval);
/**
* Hash key data.
* @param k: the key, array of uint8_t
* @param length: the length of the key, in uint8_ts
* @param initval: the previous hash, or an arbitrary value
* @return: hash value.
*/
uint32_t hashlittle(const void *k, size_t length, uint32_t initval);
/**
* Set the randomisation initial value, set this before threads start,
* and before hashing stuff (because it changes subsequent results).
* @param v: value
*/
void hash_set_raninit(uint32_t v);
#endif /* UTIL_STORAGE_LOOKUP3_H */