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-rw-r--r--src/libs/7zip/win/CPP/7zip/Compress/Mtf8.h193
1 files changed, 193 insertions, 0 deletions
diff --git a/src/libs/7zip/win/CPP/7zip/Compress/Mtf8.h b/src/libs/7zip/win/CPP/7zip/Compress/Mtf8.h
new file mode 100644
index 000000000..d15dd4a56
--- /dev/null
+++ b/src/libs/7zip/win/CPP/7zip/Compress/Mtf8.h
@@ -0,0 +1,193 @@
+// Mtf8.h
+
+#ifndef __COMPRESS_MTF8_H
+#define __COMPRESS_MTF8_H
+
+#include "../../../C/CpuArch.h"
+
+#include "../../Common/Types.h"
+
+namespace NCompress {
+
+struct CMtf8Encoder
+{
+ Byte Buf[256];
+
+ int FindAndMove(Byte v)
+ {
+ int pos;
+ for (pos = 0; Buf[pos] != v; pos++);
+ int resPos = pos;
+ for (; pos >= 8; pos -= 8)
+ {
+ Buf[pos] = Buf[pos - 1];
+ Buf[pos - 1] = Buf[pos - 2];
+ Buf[pos - 2] = Buf[pos - 3];
+ Buf[pos - 3] = Buf[pos - 4];
+ Buf[pos - 4] = Buf[pos - 5];
+ Buf[pos - 5] = Buf[pos - 6];
+ Buf[pos - 6] = Buf[pos - 7];
+ Buf[pos - 7] = Buf[pos - 8];
+ }
+ for (; pos > 0; pos--)
+ Buf[pos] = Buf[pos - 1];
+ Buf[0] = v;
+ return resPos;
+ }
+};
+
+/*
+struct CMtf8Decoder
+{
+ Byte Buf[256];
+
+ void Init(int) {};
+ Byte GetHead() const { return Buf[0]; }
+ Byte GetAndMove(int pos)
+ {
+ Byte res = Buf[pos];
+ for (; pos >= 8; pos -= 8)
+ {
+ Buf[pos] = Buf[pos - 1];
+ Buf[pos - 1] = Buf[pos - 2];
+ Buf[pos - 2] = Buf[pos - 3];
+ Buf[pos - 3] = Buf[pos - 4];
+ Buf[pos - 4] = Buf[pos - 5];
+ Buf[pos - 5] = Buf[pos - 6];
+ Buf[pos - 6] = Buf[pos - 7];
+ Buf[pos - 7] = Buf[pos - 8];
+ }
+ for (; pos > 0; pos--)
+ Buf[pos] = Buf[pos - 1];
+ Buf[0] = res;
+ return res;
+ }
+};
+*/
+
+#ifdef MY_CPU_64BIT
+typedef UInt64 CMtfVar;
+#define MTF_MOVS 3
+#else
+typedef UInt32 CMtfVar;
+#define MTF_MOVS 2
+#endif
+
+#define MTF_MASK ((1 << MTF_MOVS) - 1)
+
+
+struct CMtf8Decoder
+{
+ CMtfVar Buf[256 >> MTF_MOVS];
+
+ void StartInit() { memset(Buf, 0, sizeof(Buf)); }
+ void Add(unsigned int pos, Byte val) { Buf[pos >> MTF_MOVS] |= ((CMtfVar)val << ((pos & MTF_MASK) << 3)); }
+ Byte GetHead() const { return (Byte)Buf[0]; }
+ Byte GetAndMove(unsigned int pos)
+ {
+ UInt32 lim = ((UInt32)pos >> MTF_MOVS);
+ pos = (pos & MTF_MASK) << 3;
+ CMtfVar prev = (Buf[lim] >> pos) & 0xFF;
+
+ UInt32 i = 0;
+ if ((lim & 1) != 0)
+ {
+ CMtfVar next = Buf[0];
+ Buf[0] = (next << 8) | prev;
+ prev = (next >> (MTF_MASK << 3));
+ i = 1;
+ lim -= 1;
+ }
+ for (; i < lim; i += 2)
+ {
+ CMtfVar n0 = Buf[i];
+ CMtfVar n1 = Buf[i + 1];
+ Buf[i ] = (n0 << 8) | prev;
+ Buf[i + 1] = (n1 << 8) | (n0 >> (MTF_MASK << 3));
+ prev = (n1 >> (MTF_MASK << 3));
+ }
+ CMtfVar next = Buf[i];
+ CMtfVar mask = (((CMtfVar)0x100 << pos) - 1);
+ Buf[i] = (next & ~mask) | (((next << 8) | prev) & mask);
+ return (Byte)Buf[0];
+ }
+};
+
+/*
+const int kSmallSize = 64;
+class CMtf8Decoder
+{
+ Byte SmallBuffer[kSmallSize];
+ int SmallSize;
+ Byte Counts[16];
+ int Size;
+public:
+ Byte Buf[256];
+
+ Byte GetHead() const
+ {
+ if (SmallSize > 0)
+ return SmallBuffer[kSmallSize - SmallSize];
+ return Buf[0];
+ }
+
+ void Init(int size)
+ {
+ Size = size;
+ SmallSize = 0;
+ for (int i = 0; i < 16; i++)
+ {
+ Counts[i] = ((size >= 16) ? 16 : size);
+ size -= Counts[i];
+ }
+ }
+
+ Byte GetAndMove(int pos)
+ {
+ if (pos < SmallSize)
+ {
+ Byte *p = SmallBuffer + kSmallSize - SmallSize;
+ Byte res = p[pos];
+ for (; pos > 0; pos--)
+ p[pos] = p[pos - 1];
+ SmallBuffer[kSmallSize - SmallSize] = res;
+ return res;
+ }
+ if (SmallSize == kSmallSize)
+ {
+ int i = Size - 1;
+ int g = 16;
+ do
+ {
+ g--;
+ int offset = (g << 4);
+ for (int t = Counts[g] - 1; t >= 0; t--, i--)
+ Buf[i] = Buf[offset + t];
+ }
+ while(g != 0);
+
+ for (i = kSmallSize - 1; i >= 0; i--)
+ Buf[i] = SmallBuffer[i];
+ Init(Size);
+ }
+ pos -= SmallSize;
+ int g;
+ for (g = 0; pos >= Counts[g]; g++)
+ pos -= Counts[g];
+ int offset = (g << 4);
+ Byte res = Buf[offset + pos];
+ for (pos; pos < 16 - 1; pos++)
+ Buf[offset + pos] = Buf[offset + pos + 1];
+
+ SmallSize++;
+ SmallBuffer[kSmallSize - SmallSize] = res;
+
+ Counts[g]--;
+ return res;
+ }
+};
+*/
+
+}
+
+#endif