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// Declarations for hash functions. -*- C++ -*- |
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// Copyright (C) 2010-2021 Free Software Foundation, Inc. |
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// |
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// This file is part of the GNU ISO C++ Library. This library is free |
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// software; you can redistribute it and/or modify it under the |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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// Under Section 7 of GPL version 3, you are granted additional |
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// permissions described in the GCC Runtime Library Exception, version |
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// 3.1, as published by the Free Software Foundation. |
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// You should have received a copy of the GNU General Public License and |
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// a copy of the GCC Runtime Library Exception along with this program; |
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
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// <http://www.gnu.org/licenses/>. |
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/** @file bits/hash_bytes.h |
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* This is an internal header file, included by other library headers. |
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* Do not attempt to use it directly. @headername{functional} |
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*/ |
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#ifndef _HASH_BYTES_H |
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#define _HASH_BYTES_H 1 |
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#pragma GCC system_header |
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#include <bits/c++config.h> |
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namespace std |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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// Hash function implementation for the nontrivial specialization. |
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// All of them are based on a primitive that hashes a pointer to a |
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// byte array. The actual hash algorithm is not guaranteed to stay |
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// the same from release to release -- it may be updated or tuned to |
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// improve hash quality or speed. |
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size_t |
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_Hash_bytes(const void* __ptr, size_t __len, size_t __seed); |
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// A similar hash primitive, using the FNV hash algorithm. This |
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// algorithm is guaranteed to stay the same from release to release. |
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// (although it might not produce the same values on different |
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// machines.) |
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size_t |
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_Fnv_hash_bytes(const void* __ptr, size_t __len, size_t __seed); |
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_GLIBCXX_END_NAMESPACE_VERSION |
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} // namespace |
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#endif |
