108 lines
3.8 KiB
C#
108 lines
3.8 KiB
C#
|
/* This file is part of SevenZipSharp.
|
||
|
|
|
||
|
|
SevenZipSharp is free software: you can redistribute it and/or modify
|
||
|
|
it under the terms of the GNU Lesser General Public License as published by
|
||
|
|
the Free Software Foundation, either version 3 of the License, or
|
||
|
|
(at your option) any later version.
|
||
|
|
|
||
|
|
SevenZipSharp is distributed in the hope that it will be useful,
|
||
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
GNU Lesser General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
|
along with SevenZipSharp. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
namespace SevenZip.Sdk.Compression.Lzma
|
||
|
|
{
|
||
|
|
internal abstract class Base
|
||
|
|
{
|
||
|
|
public const uint kAlignMask = (kAlignTableSize - 1);
|
||
|
|
public const uint kAlignTableSize = 1 << kNumAlignBits;
|
||
|
|
public const int kDicLogSizeMin = 0;
|
||
|
|
public const uint kEndPosModelIndex = 14;
|
||
|
|
public const uint kMatchMaxLen = kMatchMinLen + kNumLenSymbols - 1;
|
||
|
|
// public const int kDicLogSizeMax = 30;
|
||
|
|
// public const uint kDistTableSizeMax = kDicLogSizeMax * 2;
|
||
|
|
|
||
|
|
public const uint kMatchMinLen = 2;
|
||
|
|
|
||
|
|
public const int kNumAlignBits = 4;
|
||
|
|
|
||
|
|
public const uint kNumFullDistances = 1 << ((int) kEndPosModelIndex/2);
|
||
|
|
public const int kNumHighLenBits = 8;
|
||
|
|
|
||
|
|
public const uint kNumLenSymbols = kNumLowLenSymbols + kNumMidLenSymbols +
|
||
|
|
(1 << kNumHighLenBits);
|
||
|
|
|
||
|
|
public const uint kNumLenToPosStates = 1 << kNumLenToPosStatesBits;
|
||
|
|
public const int kNumLenToPosStatesBits = 2; // it's for speed optimization
|
||
|
|
|
||
|
|
public const uint kNumLitContextBitsMax = 8;
|
||
|
|
public const uint kNumLitPosStatesBitsEncodingMax = 4;
|
||
|
|
|
||
|
|
public const int kNumLowLenBits = 3;
|
||
|
|
public const uint kNumLowLenSymbols = 1 << kNumLowLenBits;
|
||
|
|
public const int kNumMidLenBits = 3;
|
||
|
|
public const uint kNumMidLenSymbols = 1 << kNumMidLenBits;
|
||
|
|
public const uint kNumPosModels = kEndPosModelIndex - kStartPosModelIndex;
|
||
|
|
public const int kNumPosSlotBits = 6;
|
||
|
|
public const int kNumPosStatesBitsEncodingMax = 4;
|
||
|
|
public const int kNumPosStatesBitsMax = 4;
|
||
|
|
public const uint kNumPosStatesEncodingMax = (1 << kNumPosStatesBitsEncodingMax);
|
||
|
|
public const uint kNumPosStatesMax = (1 << kNumPosStatesBitsMax);
|
||
|
|
public const uint kNumRepDistances = 4;
|
||
|
|
public const uint kNumStates = 12;
|
||
|
|
public const uint kStartPosModelIndex = 4;
|
||
|
|
|
||
|
|
public static uint GetLenToPosState(uint len)
|
||
|
|
{
|
||
|
|
len -= kMatchMinLen;
|
||
|
|
if (len < kNumLenToPosStates)
|
||
|
|
return len;
|
||
|
|
return (kNumLenToPosStates - 1);
|
||
|
|
}
|
||
|
|
|
||
|
|
#region Nested type: State
|
||
|
|
|
||
|
|
public struct State
|
||
|
|
{
|
||
|
|
public uint Index;
|
||
|
|
|
||
|
|
public void Init()
|
||
|
|
{
|
||
|
|
Index = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
public void UpdateChar()
|
||
|
|
{
|
||
|
|
if (Index < 4) Index = 0;
|
||
|
|
else if (Index < 10) Index -= 3;
|
||
|
|
else Index -= 6;
|
||
|
|
}
|
||
|
|
|
||
|
|
public void UpdateMatch()
|
||
|
|
{
|
||
|
|
Index = (uint) (Index < 7 ? 7 : 10);
|
||
|
|
}
|
||
|
|
|
||
|
|
public void UpdateRep()
|
||
|
|
{
|
||
|
|
Index = (uint) (Index < 7 ? 8 : 11);
|
||
|
|
}
|
||
|
|
|
||
|
|
public void UpdateShortRep()
|
||
|
|
{
|
||
|
|
Index = (uint) (Index < 7 ? 9 : 11);
|
||
|
|
}
|
||
|
|
|
||
|
|
public bool IsCharState()
|
||
|
|
{
|
||
|
|
return Index < 7;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#endregion
|
||
|
|
}
|
||
|
|
}
|