apps/plugins/lib/jhash.h

   1 /***************************************************************************
   2 *             __________               __   ___.
   3 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7 *                     \/            \/     \/    \/            \/
   8 * $Id$
   9 *
  10 * Copyright (C) 2009 by Andrew Mahone
  11 *
  12 * jhash.c headers
  13 *
  14 * This program is free software; you can redistribute it and/or
  15 * modify it under the terms of the GNU General Public License
  16 * as published by the Free Software Foundation; either version 2
  17 * of the License, or (at your option) any later version.
  18 *
  19 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  20 * KIND, either express or implied.
  21 *
  22 ****************************************************************************/
  23
  24 #ifndef _LIB_JHASH_H_
  25 #define _LIB_JHASH_H_
  26 #include <inttypes.h>     /* defines uint32_t etc */
  27 #include <sys/types.h>
  28 #include <plugin.h>
  29
  30 /*
  31 hashw() -- hash an array of uint32_t into a 32-bit value
  32   k:       pointer to the key, an array of uint32_t
  33   length:  number of elements in the key
  34   initval: an initialization value
  35   returns the 32-bit hash
  36 */
  37 uint32_t hashw(const uint32_t *k, size_t length, uint32_t  initval);
  38
  39 /*
  40 hashw() -- hash an array of uint32_t into two 32-bit values
  41 (*pc) will be the same as the return value from hashword().
  42   k:      pointer to the key, an array of uint32_t
  43   length: number of elements in the key
  44   pc, pb: pointers to primary and secondary initial values, also used to store
  45           the hash results.
  46 */
  47 void hashw2 (const uint32_t *k, size_t length, uint32_t *pc, uint32_t *pb);
  48
  49 /*
  50 hashs() -- hash an array of bytes into a 32-bit value
  51   k:       pointer to the key, an array of bytes
  52   length:  number of elements in the key
  53   initval: an initialization value
  54   returns the 32-bit hash
  55 */
  56 uint32_t hashs( const void *key, size_t length, uint32_t initval);
  57
  58 /*
  59 hashs2() -- hash an array of bytes into two 32-bit values
  60   k:       pointer to the key, an array of bytes
  61   length: number of elements in the key
  62   pc, pb: pointers to primary and secondary initial values, also used to store
  63           the hash results.
  64 */
  65 void hashs2(const void *key, size_t length, uint32_t *pc, uint32_t *pb);
  66 #endif
  67