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Diffstat (limited to 'CS/7zip/Compress/LZMA/LzmaBase.cs')
-rwxr-xr-xCS/7zip/Compress/LZMA/LzmaBase.cs76
1 files changed, 76 insertions, 0 deletions
diff --git a/CS/7zip/Compress/LZMA/LzmaBase.cs b/CS/7zip/Compress/LZMA/LzmaBase.cs
new file mode 100755
index 0000000..8447a2a
--- /dev/null
+++ b/CS/7zip/Compress/LZMA/LzmaBase.cs
@@ -0,0 +1,76 @@
+// LzmaBase.cs
+
+namespace SevenZip.Compression.LZMA
+{
+ internal abstract class Base
+ {
+ public const uint kNumRepDistances = 4;
+ public const uint kNumStates = 12;
+
+ // static byte []kLiteralNextStates = {0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5};
+ // static byte []kMatchNextStates = {7, 7, 7, 7, 7, 7, 7, 10, 10, 10, 10, 10};
+ // static byte []kRepNextStates = {8, 8, 8, 8, 8, 8, 8, 11, 11, 11, 11, 11};
+ // static byte []kShortRepNextStates = {9, 9, 9, 9, 9, 9, 9, 11, 11, 11, 11, 11};
+
+ 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; }
+ }
+
+ public const int kNumPosSlotBits = 6;
+ public const int kDicLogSizeMin = 0;
+ // public const int kDicLogSizeMax = 30;
+ // public const uint kDistTableSizeMax = kDicLogSizeMax * 2;
+
+ public const int kNumLenToPosStatesBits = 2; // it's for speed optimization
+ public const uint kNumLenToPosStates = 1 << kNumLenToPosStatesBits;
+
+ public const uint kMatchMinLen = 2;
+
+ public static uint GetLenToPosState(uint len)
+ {
+ len -= kMatchMinLen;
+ if (len < kNumLenToPosStates)
+ return len;
+ return (uint)(kNumLenToPosStates - 1);
+ }
+
+ public const int kNumAlignBits = 4;
+ public const uint kAlignTableSize = 1 << kNumAlignBits;
+ public const uint kAlignMask = (kAlignTableSize - 1);
+
+ public const uint kStartPosModelIndex = 4;
+ public const uint kEndPosModelIndex = 14;
+ public const uint kNumPosModels = kEndPosModelIndex - kStartPosModelIndex;
+
+ public const uint kNumFullDistances = 1 << ((int)kEndPosModelIndex / 2);
+
+ public const uint kNumLitPosStatesBitsEncodingMax = 4;
+ public const uint kNumLitContextBitsMax = 8;
+
+ public const int kNumPosStatesBitsMax = 4;
+ public const uint kNumPosStatesMax = (1 << kNumPosStatesBitsMax);
+ public const int kNumPosStatesBitsEncodingMax = 4;
+ public const uint kNumPosStatesEncodingMax = (1 << kNumPosStatesBitsEncodingMax);
+
+ public const int kNumLowLenBits = 3;
+ public const int kNumMidLenBits = 3;
+ public const int kNumHighLenBits = 8;
+ public const uint kNumLowLenSymbols = 1 << kNumLowLenBits;
+ public const uint kNumMidLenSymbols = 1 << kNumMidLenBits;
+ public const uint kNumLenSymbols = kNumLowLenSymbols + kNumMidLenSymbols +
+ (1 << kNumHighLenBits);
+ public const uint kMatchMaxLen = kMatchMinLen + kNumLenSymbols - 1;
+ }
+}