33 lines
709 B
C#
33 lines
709 B
C#
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namespace Crysome.Common.Network.FileTransfer;
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internal static class Crc32
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{
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private static readonly uint[] _table = Build();
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private static uint[] Build()
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{
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uint[] array = new uint[256];
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for (uint num = 0u; num < 256; num++)
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{
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uint num2 = num;
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for (int i = 0; i < 8; i++)
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{
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num2 = (((num2 & 1) != 0) ? (0xEDB88320u ^ (num2 >> 1)) : (num2 >> 1));
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}
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array[num] = num2;
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}
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return array;
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}
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internal static uint Compute(byte[] data, int offset, int len)
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{
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uint num = uint.MaxValue;
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int num2 = offset + len;
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for (int i = offset; i < num2; i++)
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{
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num = (num >> 8) ^ _table[(num ^ data[i]) & 0xFF];
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}
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return num ^ 0xFFFFFFFFu;
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}
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}
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