35 lines
1.2 KiB
C#
35 lines
1.2 KiB
C#
using System;
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namespace libsharperang {
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public class DataTransforms {
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public CRC32 hasher;
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private uint MagicNumber=0x35769521;
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public bool IsCrcInitialised() => (hasher!=null && hasher.Initialised);
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public void InitialiseCrc(uint Key = 0x35769521) {
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if (hasher==null || (hasher.Initialised && hasher.Initial != Key)) hasher=new CRC32(Key);
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hasher.Initialise();
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}
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public byte[] GetHashSum(byte[] data) {
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if (!IsCrcInitialised()) InitialiseCrc();
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return BitConverter.GetBytes(hasher.GetChecksum(data));
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}
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public uint GetCrcKey() {
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if (!IsCrcInitialised()) InitialiseCrc();
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return hasher.Initial == MagicNumber ? hasher.Initial : hasher.Initial ^ MagicNumber;
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}
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public byte[] GetCrcKeyBytes() {
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if (!IsCrcInitialised()) InitialiseCrc();
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return BitConverter.GetBytes(GetCrcKey());
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}
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public byte[] GeneratePrintOpcode(byte[] data) => BitConverter.GetBytes(SwapEndianness(
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0x00010000 | (((((
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(uint)data.Length & 0xFFU) << 16) |
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(uint)data.Length) & 0xFFFF00U) >> 8)));
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public uint SwapEndianness(uint value) => (
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(value & 0x000000FFU) << 24) |
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((value & 0x0000FF00U) << 8) |
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((value & 0x00FF0000U) >> 8) |
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((value & 0xFF000000U) >> 24);
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}
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}
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