48 lines
1.1 KiB
C
48 lines
1.1 KiB
C
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// //////////////////////////////////////////////////////////
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// crc32.h
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// Copyright (c) 2014 Stephan Brumme. All rights reserved.
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// see http://create.stephan-brumme.com/disclaimer.html
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//
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#pragma once
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#include "../hashing.h"
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/// compute CRC32 hash, based on Intel's Slicing-by-8 algorithm
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/** Usage:
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CRC32 crc32;
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std::string myHash = crc32("Hello World"); // std::string
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std::string myHash2 = crc32("How are you", 11); // arbitrary data, 11 bytes
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// or in a streaming fashion:
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CRC32 crc32;
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while (more data available)
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crc32.add(pointer to fresh data, number of new bytes);
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std::string myHash3 = crc32.getHash();
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*/
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class CRC32 //: public Hash
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{
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public:
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/// same as reset()
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CRC32();
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/// compute CRC32 of a memory block
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const char* operator()(const void* data, size_t numBytes);
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/// compute CRC32 of a string, excluding final zero
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const char* operator()(const char* text, size_t size);
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/// add arbitrary number of bytes
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void add(const void* data, size_t numBytes);
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/// return latest hash as 16 hex characters
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const char* getHash();
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/// restart
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void reset();
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private:
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/// hash
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uint32_t m_hash;
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};
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