haproxy/include/common/hash.h
Willy Tarreau c829ee48c7 MINOR: hash: add new function hash_crc32
This function will be used to perform CRC32 computations. This one wa
loosely inspired from crc32b found here, and focuses on size and speed
at the same time :

    http://www.hackersdelight.org/hdcodetxt/crc.c.txt

Much faster table-based versions exist but are pointless for our usage
here, this hash already sustains gigabit speed which is far faster than
what we'd ever need. Better preserve the CPU's cache instead.
2015-01-20 19:48:05 +01:00

31 lines
1.1 KiB
C

/*
* include/common/hash.h
* Macros for different hashing function.
*
* Copyright (C) 2000-2011 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _COMMON_HASH_H_
#define _COMMON_HASH_H_
unsigned int hash_djb2(const char *key, int len);
unsigned int hash_wt6(const char *key, int len);
unsigned int hash_sdbm(const char *key, int len);
unsigned int hash_crc32(const char *key, int len);
#endif /* _COMMON_HASH_H_ */