mirror of
https://github.com/RGBCube/serenity
synced 2025-10-31 10:42:45 +00:00
649d2faeab
We had some inconsistencies before: - Sometimes "The", sometimes "the" - Sometimes trailing ".", sometimes no trailing "." I picked the most common one (lowecase "the", trailing ".") and applied it to all copyright headers. By using the exact same string everywhere we can ensure nothing gets missed during a global search (and replace), and that these inconsistencies are not spread any further (as copyright headers are commonly copied to new files).
65 lines
1.1 KiB
C++
65 lines
1.1 KiB
C++
/*
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* Copyright (c) 2020, the SerenityOS developers.
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#pragma once
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#include <AK/Span.h>
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#include <AK/Types.h>
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#include <LibCrypto/Checksum/ChecksumFunction.h>
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namespace Crypto::Checksum {
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struct Table {
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u32 data[256];
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constexpr Table()
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: data()
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{
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for (auto i = 0; i < 256; i++) {
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u32 value = i;
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for (auto j = 0; j < 8; j++) {
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if (value & 1) {
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value = 0xEDB88320 ^ (value >> 1);
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} else {
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value = value >> 1;
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}
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}
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data[i] = value;
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}
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}
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constexpr u32 operator[](int index) const
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{
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return data[index];
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}
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};
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constexpr static auto table = Table();
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class CRC32 : public ChecksumFunction<u32> {
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public:
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CRC32() { }
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CRC32(ReadonlyBytes data)
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{
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update(data);
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}
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CRC32(u32 initial_state, ReadonlyBytes data)
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: m_state(initial_state)
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{
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update(data);
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}
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void update(ReadonlyBytes data);
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u32 digest();
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private:
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u32 m_state { ~0u };
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};
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}
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