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/*
* Copyright (c) 2010-2013 BitTorrent, Inc.
*
* 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.
*/
#include "utp_hash.h"
#include "utp_types.h"
#ifdef STRICT_ALIGN
inline uint32 Read32(const void *p)
{
uint32 tmp;
memcpy(&tmp, p, sizeof tmp);
return tmp;
}
#else
inline uint32 Read32(const void *p) { return *(uint32*)p; }
#endif
uint utp_hash_mem(const void *keyp, size_t keysize)
{
uint hash = 0;
uint n = keysize;
while (n >= 4) {
hash ^= Read32(keyp);
keyp = (byte*)keyp + sizeof(uint32);
hash = (hash << 13) | (hash >> 19);
n -= 4;
}
while (n != 0) {
hash ^= *(byte*)keyp;
keyp = (byte*)keyp + sizeof(byte);
hash = (hash << 8) | (hash >> 24);
n--;
}
return hash;
}
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