digest.hpp
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//
// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// Official repository: https://github.com/boostorg/json
//
#ifndef BOOST_JSON_DETAIL_DIGEST_HPP
#define BOOST_JSON_DETAIL_DIGEST_HPP
BOOST_JSON_NS_BEGIN
namespace detail {
// Calculate salted digest of string
template<class ForwardIterator>
std::size_t
digest(
ForwardIterator b,
ForwardIterator e,
std::size_t salt) noexcept
{
#if BOOST_JSON_ARCH == 64
std::uint64_t const prime = 0x100000001B3ULL;
std::uint64_t hash = 0xcbf29ce484222325ULL;
#else
std::uint32_t const prime = 0x01000193UL;
std::uint32_t hash = 0x811C9DC5UL;
#endif
hash += salt;
for(; b != e; ++b)
hash = (*b ^ hash) * prime;
return hash;
}
} // detail
BOOST_JSON_NS_END
#endif