niko
103 lines
2.2 KiB
C#
103 lines
2.2 KiB
C#
using System;
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namespace Hjg.Pngcs.Zlib
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{
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// Token: 0x02000047 RID: 71
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public class CRC32
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{
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// Token: 0x060002A4 RID: 676 RVA: 0x0000A90A File Offset: 0x00008B0A
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public CRC32()
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: this(3988292384U, uint.MaxValue)
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{
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}
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// Token: 0x060002A5 RID: 677 RVA: 0x0000A918 File Offset: 0x00008B18
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public CRC32(uint polynomial, uint seed)
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{
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this.table = CRC32.InitializeTable(polynomial);
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this.seed = seed;
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this.hash = seed;
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}
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// Token: 0x060002A6 RID: 678 RVA: 0x0000A93A File Offset: 0x00008B3A
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public void Update(byte[] buffer)
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{
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this.Update(buffer, 0, buffer.Length);
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}
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// Token: 0x060002A7 RID: 679 RVA: 0x0000A948 File Offset: 0x00008B48
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public void Update(byte[] buffer, int start, int length)
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{
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int i = 0;
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int num = start;
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while (i < length)
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{
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this.hash = (this.hash >> 8) ^ this.table[(int)((UIntPtr)((uint)buffer[num] ^ (this.hash & 255U)))];
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i++;
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num++;
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}
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}
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// Token: 0x060002A8 RID: 680 RVA: 0x0000A98E File Offset: 0x00008B8E
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public uint GetValue()
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{
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return ~this.hash;
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}
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// Token: 0x060002A9 RID: 681 RVA: 0x0000A997 File Offset: 0x00008B97
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public void Reset()
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{
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this.hash = this.seed;
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}
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// Token: 0x060002AA RID: 682 RVA: 0x0000A9A8 File Offset: 0x00008BA8
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private static uint[] InitializeTable(uint polynomial)
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{
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if (polynomial == 3988292384U && CRC32.defaultTable != null)
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{
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return CRC32.defaultTable;
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}
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uint[] array = new uint[256];
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for (int i = 0; i < 256; i++)
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{
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uint num = (uint)i;
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for (int j = 0; j < 8; j++)
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{
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if ((num & 1U) == 1U)
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{
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num = (num >> 1) ^ polynomial;
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}
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else
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{
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num >>= 1;
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}
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}
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array[i] = num;
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}
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if (polynomial == 3988292384U)
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{
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CRC32.defaultTable = array;
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}
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return array;
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}
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// Token: 0x0400015D RID: 349
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private const uint defaultPolynomial = 3988292384U;
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// Token: 0x0400015E RID: 350
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private const uint defaultSeed = 4294967295U;
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// Token: 0x0400015F RID: 351
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private static uint[] defaultTable;
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// Token: 0x04000160 RID: 352
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private uint hash;
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// Token: 0x04000161 RID: 353
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private uint seed;
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// Token: 0x04000162 RID: 354
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private uint[] table;
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}
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}
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