elexis
43137fef3f
Differential Revision: https://code.wildfiregames.com/D716
Refs 09e974e1cb
Reviewed By: bb
Change in agreement with leper.
This was SVN commit r19899.
56 lines
2.0 KiB
C
56 lines
2.0 KiB
C
/* Copyright (C) 2010 Wildfire Games.
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included
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* in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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/*
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* Fowler/Noll/Vo string hash
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*/
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#ifndef INCLUDED_FNV_HASH
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#define INCLUDED_FNV_HASH
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/**
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* rationale: this algorithm was chosen because it delivers 'good' results
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* for string data and is relatively simple. other good alternatives exist;
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* see Ozan Yigit's hash roundup.
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**/
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/**
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* calculate FNV1-A hash.
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*
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* @param buf input buffer.
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* @param len if 0 (default), treat buf as a C-string; otherwise,
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* indicates how many bytes of buffer to hash.
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* @return hash result. note: results are distinct for buffers containing
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* differing amounts of zero bytes because the hash value is seeded.
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**/
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extern u32 fnv_hash(const void* buf, size_t len = 0);
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/// 64-bit version of fnv_hash.
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extern u64 fnv_hash64(const void* buf, size_t len = 0);
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/**
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* special version of fnv_hash for strings: first converts to lowercase
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* (useful for comparing mixed-case filenames)
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**/
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extern u32 fnv_lc_hash(const char* str, size_t len = 0);
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#endif // #ifndef INCLUDED_FNV_HASH
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