50 lines
1.3 KiB
C++
50 lines
1.3 KiB
C++
/*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Copyright 2011 Danny Robson <danny@nerdcruft.net>
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*/
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#ifndef __UTIL_HASH_CRC_HPP
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#define __UTIL_HASH_CRC_HPP
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#include <cstdint>
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#include <cstdlib>
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///////////////////////////////////////////////////////////////////////////////
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namespace util::hash {
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// Implements the crc32 checksum (from ethernet, png, etc).
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// Adapted from the PNG specification (ISO/IEC 15948:2003), appendix D.
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class crc32 {
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public:
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using digest_t = uint32_t;
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crc32 () noexcept;
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void reset (void) noexcept;
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void update (const void *restrict data, size_t bytes) noexcept;
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void update (const uint8_t *restrict first, const uint8_t *restrict last) noexcept;
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void finish (void);
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digest_t digest (void) const;
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private:
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digest_t m_digest;
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};
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}
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#endif
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