2016-10-28 14:45:28 +11:00

75 lines
2.3 KiB
C++

/*
* Copyright (c) 2016, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER OR CONTRIBUTORS 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.
*/
/**
* \file
* \brief Hashing utility functions.
*/
#ifndef UTIL_HASH_H
#define UTIL_HASH_H
#include <boost/functional/hash/hash_fwd.hpp>
namespace ue2 {
namespace hash_detail {
template<typename T>
void hash_build(size_t &v, const T &obj) {
boost::hash_combine(v, obj);
}
template<typename T, typename... Args>
void hash_build(size_t &v, const T &obj, Args&&... args) {
hash_build(v, obj);
hash_build(v, args...); // recursive
}
} // namespace hash_detail
/**
* \brief Computes the combined hash of all its arguments.
*
* Simply use:
*
* size_t hash = hash_all(a, b, c, d);
*
* Where a, b, c and d are hashable.
*/
template<typename... Args>
size_t hash_all(Args&&... args) {
size_t v = 0;
hash_detail::hash_build(v, args...);
return v;
}
} // namespace ue2
#endif // UTIL_HASH_H