mirror of https://github.com/bsnes-emu/bsnes.git
44 lines
763 B
C++
44 lines
763 B
C++
#ifndef NALL_HASH_CRC16_HPP
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#define NALL_HASH_CRC16_HPP
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#include <nall/range.hpp>
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namespace nall {
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struct string;
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namespace Hash {
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struct CRC16 {
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CRC16() { reset(); }
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CRC16(const void* values, unsigned size) : CRC16() { data(values, size); }
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auto reset() -> void {
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checksum = ~0;
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}
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auto data(uint8_t value) -> void {
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for(auto n : range(8)) {
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if((checksum & 1) ^ (value & 1)) checksum = (checksum >> 1) ^ 0x8408;
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else checksum >>= 1;
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value >>= 1;
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}
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}
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auto data(const void* values, unsigned size) -> void {
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auto p = (const uint8_t*)values;
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while(size--) data(*p++);
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}
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auto value() -> uint16_t {
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return ~checksum;
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}
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inline auto digest() -> string;
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private:
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uint16_t checksum;
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};
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}}
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#endif
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