libfreerdp-codec: fix ncrush_find_best_match
This commit is contained in:
Marc-André Moreau
parent
acf119f9f3
commit
6ca7fc2894
@ -2067,117 +2067,112 @@ int ncrush_find_match_length(BYTE* Ptr1, BYTE* Ptr2, BYTE* HistoryPtr)
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return Ptr1 - (Ptr + 1);
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}
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int ncrush_find_best_match(NCRUSH_CONTEXT* ncrush, UINT32 HistoryOffset, UINT32* pCopyOffset)
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int ncrush_find_best_match(NCRUSH_CONTEXT* ncrush, UINT16 HistoryOffset, UINT32* pMatchOffset)
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{
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int i, j;
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int Length;
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int MatchLength;
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BYTE* MatchPtr;
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UINT16 Offset;
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UINT16 _Offset;
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UINT16 CopyOffset;
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UINT16 NextOffset;
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UINT16 MatchOffset;
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BYTE* HistoryBuffer;
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if (!ncrush->MatchTable[HistoryOffset])
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return -1;
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i = 4;
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MatchLength = 2;
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Offset = HistoryOffset;
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HistoryBuffer = (BYTE*) ncrush->HistoryBuffer;
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ncrush->MatchTable[0] = HistoryOffset;
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CopyOffset = ncrush->MatchTable[HistoryOffset];
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MatchOffset = ncrush->MatchTable[HistoryOffset];
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_Offset = ncrush->MatchTable[Offset];
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NextOffset = ncrush->MatchTable[Offset];
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MatchPtr = &HistoryBuffer[MatchLength];
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while (--i < 0)
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for (i = 0; i < 4; i++)
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{
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j = 0;
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j = -1;
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if (j == 0)
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if (j < 0)
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{
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Offset = ncrush->MatchTable[_Offset];
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if (MatchPtr[_Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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Offset = _Offset;
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j++;
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}
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Offset = ncrush->MatchTable[NextOffset];
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if (MatchPtr[NextOffset] == HistoryBuffer[HistoryOffset + MatchLength])
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j = 0;
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}
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if (j == 1)
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if (j < 0)
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{
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_Offset = ncrush->MatchTable[Offset];
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NextOffset = ncrush->MatchTable[Offset];
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if (MatchPtr[Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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j++;
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}
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j = 1;
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}
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if (j == 2)
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if (j < 0)
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{
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Offset = ncrush->MatchTable[_Offset];
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if (MatchPtr[_Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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Offset = _Offset;
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j++;
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}
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Offset = ncrush->MatchTable[NextOffset];
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if (MatchPtr[NextOffset] == HistoryBuffer[HistoryOffset + MatchLength])
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j = 2;
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}
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if (j == 3)
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if (j < 0)
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{
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_Offset = ncrush->MatchTable[Offset];
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NextOffset = ncrush->MatchTable[Offset];
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if (MatchPtr[Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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j++;
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}
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j = 3;
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}
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if (j < 0)
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{
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Offset = ncrush->MatchTable[NextOffset];
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if (MatchPtr[NextOffset] == HistoryBuffer[HistoryOffset + MatchLength])
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j = 4;
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}
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if (j == 4)
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if (j < 0)
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{
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Offset = ncrush->MatchTable[_Offset];
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if (MatchPtr[_Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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Offset = _Offset;
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j++;
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}
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}
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if (j == 5)
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{
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_Offset = ncrush->MatchTable[Offset];
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NextOffset = ncrush->MatchTable[Offset];
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if (MatchPtr[Offset] == HistoryBuffer[HistoryOffset + MatchLength])
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{
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j++;
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}
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j = 5;
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}
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if (j && (Offset != (HistoryOffset && Offset)))
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if (j >= 0)
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{
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Length = ncrush_find_match_length(&HistoryBuffer[HistoryOffset + 2],
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if ((j % 2) == 0)
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Offset = NextOffset;
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if ((Offset != HistoryOffset) && Offset)
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{
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Length = ncrush_find_match_length(&HistoryBuffer[HistoryOffset + 2],
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&HistoryBuffer[Offset + 2], ncrush->HistoryPtr) + 2;
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if (Length < 2)
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return -1;
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if ((Length <= MatchLength)
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|| ((MatchLength = Length, CopyOffset = Offset,
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(&HistoryBuffer[HistoryOffset + 2] < ncrush->HistoryPtr))
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&& (Length <= 16)))
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{
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_Offset = ncrush->MatchTable[Offset];
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MatchPtr = &HistoryBuffer[MatchLength];
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continue;
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}
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if (Length < 2)
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return -1;
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if (Length > 16)
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break;
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if (Length > MatchLength)
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{
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MatchLength = Length;
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MatchOffset = Offset;
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}
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if ((Length <= MatchLength) || (&HistoryBuffer[HistoryOffset + 2] < ncrush->HistoryPtr))
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{
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NextOffset = ncrush->MatchTable[Offset];
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MatchPtr = &HistoryBuffer[MatchLength];
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continue;
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}
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}
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break;
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}
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}
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ncrush->MatchTable[0] = 0;
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*pCopyOffset = CopyOffset;
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*pMatchOffset = MatchOffset;
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return MatchLength;
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}
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@ -2252,6 +2247,7 @@ int ncrush_compress(NCRUSH_CONTEXT* ncrush, BYTE* pSrcData, UINT32 SrcSize, BYTE
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UINT32 CodeLEC;
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UINT32 BitLength;
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UINT32 CopyOffset;
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UINT32 MatchOffset;
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UINT32 OldCopyOffset;
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UINT32* OffsetCache;
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UINT32 OffsetCacheIndex;
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@ -2300,9 +2296,10 @@ int ncrush_compress(NCRUSH_CONTEXT* ncrush, BYTE* pSrcData, UINT32 SrcSize, BYTE
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HistoryBufferSize = ncrush->HistoryBufferSize;
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CopyOffset = 0;
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MatchOffset = 0;
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ncrush_hash_table_add(ncrush, pSrcData, SrcSize, HistoryPtr - HistoryBuffer);
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CopyMemory(HistoryPtr, pSrcData, SrcSize);
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ncrush->HistoryPtr = HistoryPtr + SrcSize;
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ncrush->HistoryPtr = &HistoryPtr[SrcSize];
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while (SrcPtr < (SrcEndPtr - 2))
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{
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@ -2317,15 +2314,17 @@ int ncrush_compress(NCRUSH_CONTEXT* ncrush, BYTE* pSrcData, UINT32 SrcSize, BYTE
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if (ncrush->MatchTable[HistoryOffset])
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{
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CopyOffset = 0;
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MatchLength = ncrush_find_best_match(ncrush, HistoryOffset, &CopyOffset);
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MatchOffset = 0;
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MatchLength = ncrush_find_best_match(ncrush, HistoryOffset, &MatchOffset);
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if (MatchLength == -1)
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return -1;
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}
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if (MatchLength)
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CopyOffset = (HistoryBufferSize - 1) & (HistoryPtr - &HistoryBuffer[CopyOffset]);
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CopyOffset = (HistoryBufferSize - 1) & (HistoryPtr - &HistoryBuffer[MatchOffset]);
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printf("MatchLength: %d MatchOffset: %d CopyOffset: %d\n", MatchLength, MatchOffset, CopyOffset);
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if ((MatchLength == 2) && (CopyOffset >= 64))
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MatchLength = 0;
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@ -2362,8 +2361,8 @@ int ncrush_compress(NCRUSH_CONTEXT* ncrush, BYTE* pSrcData, UINT32 SrcSize, BYTE
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HistoryPtr += MatchLength;
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SrcPtr += MatchLength;
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printf("MatchLength: %d CopyOffset: %d Offset: %d\n", MatchLength, CopyOffset,
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(int) (DstPtr - pDstData));
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printf("MatchLength: %d CopyOffset: %d Offset: %d\n",
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MatchLength, CopyOffset, (int) (DstPtr - pDstData));
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if (!MatchLength)
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return -1;
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@ -2442,8 +2441,8 @@ int ncrush_compress(NCRUSH_CONTEXT* ncrush, BYTE* pSrcData, UINT32 SrcSize, BYTE
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BitLength = HuffLengthLEC[IndexLEC];
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CodeLEC = *((UINT16*) &HuffCodeLEC[IndexLEC * 2]);
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printf("CopyOffsetIndex: %d CopyOffsetBits: %d BitLength: %d IndexLEC: %d CodeLEC: 0x%04X Offset: %d\n",
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CopyOffsetIndex, CopyOffsetBits, BitLength, IndexLEC, CodeLEC, DstPtr - pDstData);
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printf("CopyOffset: %d bits+2: %d CopyOffsetIndex: %d CopyOffsetBits: %d BitLength: %d IndexLEC: %d CodeLEC: 0x%04X Offset: %d\n",
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CopyOffset, bits+2, CopyOffsetIndex, CopyOffsetBits, BitLength, IndexLEC, CodeLEC, DstPtr - pDstData);
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if (BitLength > 15)
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return -1;
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