~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 * Copyright (C) 1992-2007 The FreeBSD Project. All rights reserved.

 * 

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 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. 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.

 * 

 * THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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

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 */

/* 

 * The crc32 functions and data was originally written by Spencer

 * Garrett <srg@quick.com> and was gleaned from the PostgreSQL source

 * tree via the files contrib/ltree/crc32.[ch] and from FreeBSD at

 * src/usr.bin/cksum/crc32.c.

 */

#pragma once

#ifdef HAVE_SYS_TYPES_H

# include <sys/types.h>

#endif

namespace drizzled {

namespace algorithm {

static const uint32_t crc32tab[256] = 

{

  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,

  0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,

  0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,

  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,

  0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,

  0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,

  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,

  0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,

  0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,

  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,

  0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,

  0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,

  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,

  0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,

  0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,

  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,

  0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,

  0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,

  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,

  0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,

  0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,

  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,

  0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,

  0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,

  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,

  0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,

  0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,

  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,

  0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,

  0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,

  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,

  0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,

  0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,

  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,

  0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,

  0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,

  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,

  0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,

  0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,

  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,

  0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,

  0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,

  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,

  0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,

  0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,

  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,

  0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,

  0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,

  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,

  0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,

  0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,

  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,

  0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,

  0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,

  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,

  0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,

  0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,

  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,

  0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,

  0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,

  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,

  0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,

  0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,

  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,

};

template <class T>

uint32_t crc32(T key, size_t key_length)

{

  uint32_t crc= UINT32_MAX;

  for (size_t x= 0; x < key_length; x++)

    crc= (crc >> 8) ^ crc32tab[(crc ^ static_cast<uint8_t>(key[x])) & 0xff];

  return ~crc;

}

} /* namespace algorithm */

} /* namespace drizzled */