ref: 6818b86eb85580ed3634afe2a0c97c411022778f
dir: /3rd/spooky.h/
/*
* SpookyHash - 128-bit noncryptographic hash function
*
* Written in 2012 by Bob Jenkins
*
* Converted to C in 2015 by Joergen Ibsen
*
* To the extent possible under law, the author(s) have dedicated all
* copyright and related and neighboring rights to this software to the
* public domain worldwide. This software is distributed without any
* warranty. <http://creativecommons.org/publicdomain/zero/1.0/>
*
* Original comment from SpookyV2.h by Bob Jenkins:
*
* SpookyHash: a 128-bit noncryptographic hash function
* By Bob Jenkins, public domain
* Oct 31 2010: alpha, framework + SpookyHash::Mix appears right
* Oct 31 2011: alpha again, Mix only good to 2^^69 but rest appears right
* Dec 31 2011: beta, improved Mix, tested it for 2-bit deltas
* Feb 2 2012: production, same bits as beta
* Feb 5 2012: adjusted definitions of uint* to be more portable
* Mar 30 2012: 3 bytes/cycle, not 4. Alpha was 4 but wasn't thorough enough.
* August 5 2012: SpookyV2 (different results)
*
* Up to 3 bytes/cycle for long messages. Reasonably fast for short messages.
* All 1 or 2 bit deltas achieve avalanche within 1% bias per output bit.
*
* This was developed for and tested on 64-bit x86-compatible processors.
* It assumes the processor is little-endian. There is a macro
* controlling whether unaligned reads are allowed (by default they are).
* This should be an equally good hash on big-endian machines, but it will
* compute different results on them than on little-endian machines.
*
* Google's CityHash has similar specs to SpookyHash, and CityHash is faster
* on new Intel boxes. MD4 and MD5 also have similar specs, but they are orders
* of magnitude slower. CRCs are two or more times slower, but unlike
* SpookyHash, they have nice math for combining the CRCs of pieces to form
* the CRCs of wholes. There are also cryptographic hashes, but those are even
* slower than MD5.
*/
#pragma once
// number of uint64_t's in internal state
#define SC_NUMVARS 12U
// size of the internal state
#define SC_BLOCKSIZE (SC_NUMVARS * 8U)
// size of buffer of unhashed data, in bytes
#define SC_BUFSIZE (2U * SC_BLOCKSIZE)
struct spooky_state {
uint64_t data[2 * SC_NUMVARS]; // unhashed data, for partial messages
uint64_t state[SC_NUMVARS]; // internal state of the hash
size_t length; // total length of the input so far
uint8_t left; // length of unhashed data stashed in data
};
void spooky_hash128(const void *message, size_t length, uint64_t *hash1, uint64_t *hash2);
uint64_t spooky_hash64(const void *message, size_t length, uint64_t seed);
uint32_t spooky_hash32(const void *message, size_t length, uint32_t seed);
//void spooky_init(struct spooky_state *state, uint64_t seed1, uint64_t seed2);
//void spooky_update(struct spooky_state *state, const void *message, size_t length);
//void spooky_final(struct spooky_state *state, uint64_t *hash1, uint64_t *hash2);