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/*-
* Copyright 2012 Matthew Endsley
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef TINYSTL_STRINGHASH_H
#define TINYSTL_STRINGHASH_H
#include "stddef.h"
namespace tinystl {
static inline size_t hash_string(const char* str, size_t len) {
// Implementation of sdbm a public domain string hash from Ozan Yigit
// see: http://www.eecs.harvard.edu/margo/papers/usenix91/paper.ps
size_t hash = 0;
typedef const char* pointer;
for (pointer it = str, end = str + len; it != end; ++it)
hash = *it + (hash << 6) + (hash << 16) - hash;
return hash;
}
template<typename T>
inline size_t hash(const T& value) {
const size_t asint = (size_t)value;
return hash_string((const char*)&asint, sizeof(asint));
}
}
#endif
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