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/* Copyright (C) 2010 Wildfire Games.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* Fowler/Noll/Vo string hash
*/
#ifndef INCLUDED_FNV_HASH
#define INCLUDED_FNV_HASH
/**
* rationale: this algorithm was chosen because it delivers 'good' results
* for string data and is relatively simple. other good alternatives exist;
* see Ozan Yigit's hash roundup.
**/
/**
* calculate FNV1-A hash.
*
* @param buf input buffer.
* @param len if 0 (default), treat buf as a C-string; otherwise,
* indicates how many bytes of buffer to hash.
* @return hash result. note: results are distinct for buffers containing
* differing amounts of zero bytes because the hash value is seeded.
**/
extern u32 fnv_hash(const void* buf, size_t len = 0);
/// 64-bit version of fnv_hash.
extern u64 fnv_hash64(const void* buf, size_t len = 0);
/**
* special version of fnv_hash for strings: first converts to lowercase
* (useful for comparing mixed-case filenames)
**/
extern u32 fnv_lc_hash(const char* str, size_t len = 0);
#endif // #ifndef INCLUDED_FNV_HASH
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