002-lzma_decompress.patch

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+int LzmaLenDecode(CProb *p, CRangeDecoder *rd, int posState)
+{
+  if(RangeDecoderBitDecode(p + LenChoice, rd) == 0)
+    return RangeDecoderBitTreeDecode(p + LenLow +
+        (posState << kLenNumLowBits), kLenNumLowBits, rd);
+  if(RangeDecoderBitDecode(p + LenChoice2, rd) == 0)
+    return kLenNumLowSymbols + RangeDecoderBitTreeDecode(p + LenMid +
+        (posState << kLenNumMidBits), kLenNumMidBits, rd);
+  return kLenNumLowSymbols + kLenNumMidSymbols +
+      RangeDecoderBitTreeDecode(p + LenHigh, kLenNumHighBits, rd);
+}
+
+#define kNumStates 12
+
+#define kStartPosModelIndex 4
+#define kEndPosModelIndex 14
+#define kNumFullDistances (1 << (kEndPosModelIndex >> 1))
+
+#define kNumPosSlotBits 6
+#define kNumLenToPosStates 4
+
+#define kNumAlignBits 4
+#define kAlignTableSize (1 << kNumAlignBits)
+
+#define kMatchMinLen 2
+
+#define IsMatch 0
+#define IsRep (IsMatch + (kNumStates << kNumPosBitsMax))
+#define IsRepG0 (IsRep + kNumStates)
+#define IsRepG1 (IsRepG0 + kNumStates)
+#define IsRepG2 (IsRepG1 + kNumStates)
+#define IsRep0Long (IsRepG2 + kNumStates)
+#define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax))
+#define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits))
+#define Align (SpecPos + kNumFullDistances - kEndPosModelIndex)
+#define LenCoder (Align + kAlignTableSize)
+#define RepLenCoder (LenCoder + kNumLenProbs)
+#define Literal (RepLenCoder + kNumLenProbs)
+
+#if Literal != LZMA_BASE_SIZE
+StopCompilingDueBUG
+#endif
+
+#ifdef _LZMA_OUT_READ
+
+typedef struct _LzmaVarState
+{
+  CRangeDecoder RangeDecoder;
+  Byte *Dictionary;
+  UInt32 DictionarySize;
+  UInt32 DictionaryPos;
+  UInt32 GlobalPos;
+  UInt32 Reps[4];
+  int lc;
+  int lp;
+  int pb;
+  int State;
+  int PreviousIsMatch;
+  int RemainLen;
+} LzmaVarState;
+
+int LzmaDecoderInit(
+    unsigned char *buffer, UInt32 bufferSize,
+    int lc, int lp, int pb,
+    unsigned char *dictionary, UInt32 dictionarySize,
+    #ifdef _LZMA_IN_CB
+    ILzmaInCallback *inCallback
+    #else
+    unsigned char *inStream, UInt32 inSize
+    #endif
+    )
+{
+  LzmaVarState *vs = (LzmaVarState *)buffer;
+  CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
+  UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (lc + lp));
+  UInt32 i;
+  if (bufferSize < numProbs * sizeof(CProb) + sizeof(LzmaVarState))
+    return LZMA_RESULT_NOT_ENOUGH_MEM;
+  vs->Dictionary = dictionary;
+  vs->DictionarySize = dictionarySize;
+  vs->DictionaryPos = 0;
+  vs->GlobalPos = 0;
+  vs->Reps[0] = vs->Reps[1] = vs->Reps[2] = vs->Reps[3] = 1;
+  vs->lc = lc;
+  vs->lp = lp;
+  vs->pb = pb;
+  vs->State = 0;
+  vs->PreviousIsMatch = 0;
+  vs->RemainLen = 0;
+  dictionary[dictionarySize - 1] = 0;
+  for (i = 0; i < numProbs; i++)
+    p[i] = kBitModelTotal >> 1;
+  RangeDecoderInit(&vs->RangeDecoder,
+      #ifdef _LZMA_IN_CB
+      inCallback
+      #else
+      inStream, inSize
+      #endif
+  );
+  return LZMA_RESULT_OK;
+}
+
+int LzmaDecode(unsigned char *buffer,
+    unsigned char *outStream, UInt32 outSize,
+    UInt32 *outSizeProcessed)
+{
+  LzmaVarState *vs = (LzmaVarState *)buffer;
+  CProb *p = (CProb *)(buffer + sizeof(LzmaVarState));
+  CRangeDecoder rd = vs->RangeDecoder;
+  int state = vs->State;
+  int previousIsMatch = vs->PreviousIsMatch;
+  Byte previousByte;
+  UInt32 rep0 = vs->Reps[0], rep1 = vs->Reps[1], rep2 = vs->Reps[2], rep3 = vs->Reps[3];
+  UInt32 nowPos = 0;
+  UInt32 posStateMask = (1 << (vs->pb)) - 1;
+  UInt32 literalPosMask = (1 << (vs->lp)) - 1;
+  int lc = vs->lc;
+  int len = vs->RemainLen;
+  UInt32 globalPos = vs->GlobalPos;
+
+  Byte *dictionary = vs->Dictionary;
+  UInt32 dictionarySize = vs->DictionarySize;
+  UInt32 dictionaryPos = vs->DictionaryPos;
+
+  if (len == -1)
+  {
+    *outSizeProcessed = 0;
+    return LZMA_RESULT_OK;
+  }
+
+  while(len > 0 && nowPos < outSize)
+  {
+    UInt32 pos = dictionaryPos - rep0;
+    if (pos >= dictionarySize)
+      pos += dictionarySize;
+    outStream[nowPos++] = dictionary[dictionaryPos] = dictionary[pos];
+    if (++dictionaryPos == dictionarySize)
+      dictionaryPos = 0;
+    len--;
+  }
+  if (dictionaryPos == 0)
+    previousByte = dictionary[dictionarySize - 1];
+  else
+    previousByte = dictionary[dictionaryPos - 1];
+#else
+
+int LzmaDecode(
+    Byte *buffer, UInt32 bufferSize,
+    int lc, int lp, int pb,
+    #ifdef _LZMA_IN_CB
+    ILzmaInCallback *inCallback,
+    #else
+    unsigned char *inStream, UInt32 inSize,
+    #endif
+    unsigned char *outStream, UInt32 outSize,
+    UInt32 *outSizeProcessed)
+{
+  UInt32 numProbs = Literal + ((UInt32)LZMA_LIT_SIZE << (lc + lp));
+  CProb *p = (CProb *)buffer;
+  CRangeDecoder rd;
+  UInt32 i;
+  int state = 0;
+  int previousIsMatch = 0;
+  Byte previousByte = 0;
+  UInt32 rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
+  UInt32 nowPos = 0;
+  UInt32 posStateMask = (1 << pb) - 1;
+  UInt32 literalPosMask = (1 << lp) - 1;
+  int len = 0;
+  if (bufferSize < numProbs * sizeof(CProb))
+    return LZMA_RESULT_NOT_ENOUGH_MEM;
+  for (i = 0; i < numProbs; i++)
+    p[i] = kBitModelTotal >> 1;
+  RangeDecoderInit(&rd,
+      #ifdef _LZMA_IN_CB
+      inCallback
+      #else
+      inStream, inSize
+      #endif
+      );
+#endif
+
+  *outSizeProcessed = 0;
+  while(nowPos < outSize)
+  {
+    int posState = (int)(
+        (nowPos
+        #ifdef _LZMA_OUT_READ
+        + globalPos
+        #endif
+        )
+        & posStateMask);
+    #ifdef _LZMA_IN_CB
+    if (rd.Result != LZMA_RESULT_OK)
+      return rd.Result;
+    #endif
+    if (rd.ExtraBytes != 0)
+      return LZMA_RESULT_DATA_ERROR;
+    if (RangeDecoderBitDecode(p + IsMatch + (state << kNumPosBitsMax) + posState, &rd) == 0)
+    {
+      CProb *probs = p + Literal + (LZMA_LIT_SIZE *
+        (((
+        (nowPos
+        #ifdef _LZMA_OUT_READ
+        + globalPos
+        #endif
+        )
+        & literalPosMask) << lc) + (previousByte >> (8 - lc))));
+
+      if (state < 4) state = 0;
+      else if (state < 10) state -= 3;
+      else state -= 6;
+      if (previousIsMatch)
+      {
+        Byte matchByte;
+        #ifdef _LZMA_OUT_READ
+        UInt32 pos = dictionaryPos - rep0;
+        if (pos >= dictionarySize)
+          pos += dictionarySize;
+        matchByte = dictionary[pos];
+        #else
+        matchByte = outStream[nowPos - rep0];
+        #endif
+        previousByte = LzmaLiteralDecodeMatch(probs, &rd, matchByte);
+        previousIsMatch = 0;
+      }
+      else
+        previousByte = LzmaLiteralDecode(probs, &rd);
+      outStream[nowPos++] = previousByte;
+      #ifdef _LZMA_OUT_READ
+      dictionary[dictionaryPos] = previousByte;
+      if (++dictionaryPos == dictionarySize)
+        dictionaryPos = 0;
+      #endif
+    }
+    else
+    {
+      previousIsMatch = 1;
+      if (RangeDecoderBitDecode(p + IsRep + state, &rd) == 1)
+      {
+        if (RangeDecoderBitDecode(p + IsRepG0 + state, &rd) == 0)
+        {
+          if (RangeDecoderBitDecode(p + IsRep0Long + (state << kNumPosBitsMax) + posState, &rd) == 0)
+          {
+            #ifdef _LZMA_OUT_READ
+            UInt32 pos;
+            #endif
+            if (
+               (nowPos
+                #ifdef _LZMA_OUT_READ
+                + globalPos
+                #endif
+               )
+               == 0)
+              return LZMA_RESULT_DATA_ERROR;
+            state = state < 7 ? 9 : 11;
+            #ifdef _LZMA_OUT_READ
+            pos = dictionaryPos - rep0;
+            if (pos >= dictionarySize)
+              pos += dictionarySize;
+            previousByte = dictionary[pos];
+            dictionary[dictionaryPos] = previousByte;
+            if (++dictionaryPos == dictionarySize)
+              dictionaryPos = 0;
+            #else
+            previousByte = outStream[nowPos - rep0];
+            #endif
+            outStream[nowPos++] = previousByte;
+            continue;
+          }
+        }
+        else
+        {
+          UInt32 distance;
+          if(RangeDecoderBitDecode(p + IsRepG1 + state, &rd) == 0)
+            distance = rep1;
+          else
+          {
+            if(RangeDecoderBitDecode(p + IsRepG2 + state, &rd) == 0)
+              distance = rep2;
+            else
+            {
+              distance = rep3;
+              rep3 = rep2;
+            }
+            rep2 = rep1;
+          }
+          rep1 = rep0;
+          rep0 = distance;
+        }
+        len = LzmaLenDecode(p + RepLenCoder, &rd, posState);
+        state = state < 7 ? 8 : 11;
+      }
+      else
+      {
+        int posSlot;
+        rep3 = rep2;
+        rep2 = rep1;
+        rep1 = rep0;
+        state = state < 7 ? 7 : 10;
+        len = LzmaLenDecode(p + LenCoder, &rd, posState);
+        posSlot = RangeDecoderBitTreeDecode(p + PosSlot +
+            ((len < kNumLenToPosStates ? len : kNumLenToPosStates - 1) <<
+            kNumPosSlotBits), kNumPosSlotBits, &rd);
+        if (posSlot >= kStartPosModelIndex)
+        {
+          int numDirectBits = ((posSlot >> 1) - 1);
+          rep0 = ((2 | ((UInt32)posSlot & 1)) << numDirectBits);
+          if (posSlot < kEndPosModelIndex)
+          {
+            rep0 += RangeDecoderReverseBitTreeDecode(
+                p + SpecPos + rep0 - posSlot - 1, numDirectBits, &rd);
+          }
+          else
+          {
+            rep0 += RangeDecoderDecodeDirectBits(&rd,
+                numDirectBits - kNumAlignBits) << kNumAlignBits;
+            rep0 += RangeDecoderReverseBitTreeDecode(p + Align, kNumAlignBits, &rd);
+          }
+        }
+        else
+          rep0 = posSlot;
+        rep0++;
+      }
+      if (rep0 == (UInt32)(0))
+      {
+        /* it's for stream version */
+        len = -1;
+        break;
+      }
+      if (rep0 > nowPos
+        #ifdef _LZMA_OUT_READ
+        + globalPos
+        #endif
+        )
+      {
+        return LZMA_RESULT_DATA_ERROR;
+      }
+      len += kMatchMinLen;
+      do
+      {
+        #ifdef _LZMA_OUT_READ
+        UInt32 pos = dictionaryPos - rep0;
+        if (pos >= dictionarySize)
+          pos += dictionarySize;
+        previousByte = dictionary[pos];
+        dictionary[dictionaryPos] = previousByte;
+        if (++dictionaryPos == dictionarySize)
+          dictionaryPos = 0;
+        #else
+        previousByte = outStream[nowPos - rep0];
+        #endif
+        outStream[nowPos++] = previousByte;
+        len--;
+      }
+      while(len > 0 && nowPos < outSize);
+    }
+  }
+
+  #ifdef _LZMA_OUT_READ
+  vs->RangeDecoder = rd;
+  vs->DictionaryPos = dictionaryPos;
+  vs->GlobalPos = globalPos + nowPos;
+  vs->Reps[0] = rep0;
+  vs->Reps[1] = rep1;
+  vs->Reps[2] = rep2;
+  vs->Reps[3] = rep3;
+  vs->State = state;
+  vs->PreviousIsMatch = previousIsMatch;
+  vs->RemainLen = len;
+  #endif
+
+  *outSizeProcessed = nowPos;
+  return LZMA_RESULT_OK;
+}
Index: linux-2.6.21.7/lib/Makefile
===================================================================
--- linux-2.6.21.7.orig/lib/Makefile
+++ linux-2.6.21.7/lib/Makefile
@@ -12,7 +12,7 @@ lib-$(CONFIG_SMP) += cpumask.o
 
 lib-y	+= kobject.o kref.o kobject_uevent.o klist.o
 
-obj-y += sort.o parser.o halfmd4.o debug_locks.o random32.o
+obj-y += sort.o parser.o halfmd4.o debug_locks.o random32.o bust_spinlocks.o LzmaDecode.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
@@ -56,6 +56,7 @@ obj-$(CONFIG_SMP) += percpu_counter.o
 obj-$(CONFIG_AUDIT_GENERIC) += audit.o
 
 obj-$(CONFIG_SWIOTLB) += swiotlb.o
+
 obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
 
 lib-$(CONFIG_GENERIC_BUG) += bug.o