FreeRDP/libfreerdp/codec/xcrush.c
Raul Fernandes db9052e37f Optimize function xcrush_copy_bytes()
Use memcpy to copy the bytes when we can assure that the memory areas does not overlap.
When the areas overlap, copy the area that doesn't overlap repeatly.
With this change, the copy is ~30x faster.
2020-04-25 16:25:36 +02:00

1128 lines
28 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* XCrush (RDP6.1) Bulk Data Compression
*
* Copyright 2014 Marc-Andre Moreau <marcandre.moreau@gmail.com>
* Copyright 2017 Armin Novak <armin.novak@thincast.com>
* Copyright 2017 Thincast Technologies GmbH
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <winpr/crt.h>
#include <winpr/print.h>
#include <winpr/bitstream.h>
#include <freerdp/log.h>
#include <freerdp/codec/xcrush.h>
#define TAG FREERDP_TAG("codec")
#pragma pack(push, 1)
struct _XCRUSH_MATCH_INFO
{
UINT32 MatchOffset;
UINT32 ChunkOffset;
UINT32 MatchLength;
};
typedef struct _XCRUSH_MATCH_INFO XCRUSH_MATCH_INFO;
struct _XCRUSH_CHUNK
{
UINT32 offset;
UINT32 next;
};
typedef struct _XCRUSH_CHUNK XCRUSH_CHUNK;
struct _XCRUSH_SIGNATURE
{
UINT16 seed;
UINT16 size;
};
typedef struct _XCRUSH_SIGNATURE XCRUSH_SIGNATURE;
struct _RDP61_MATCH_DETAILS
{
UINT16 MatchLength;
UINT16 MatchOutputOffset;
UINT32 MatchHistoryOffset;
};
typedef struct _RDP61_MATCH_DETAILS RDP61_MATCH_DETAILS;
struct _RDP61_COMPRESSED_DATA
{
BYTE Level1ComprFlags;
BYTE Level2ComprFlags;
UINT16 MatchCount;
RDP61_MATCH_DETAILS* MatchDetails;
BYTE* Literals;
};
typedef struct _RDP61_COMPRESSED_DATA RDP61_COMPRESSED_DATA;
#pragma pack(pop)
struct _XCRUSH_CONTEXT
{
BOOL Compressor;
MPPC_CONTEXT* mppc;
BYTE* HistoryPtr;
UINT32 HistoryOffset;
UINT32 HistoryBufferSize;
BYTE HistoryBuffer[2000000];
BYTE BlockBuffer[16384];
UINT32 CompressionFlags;
UINT32 SignatureIndex;
UINT32 SignatureCount;
XCRUSH_SIGNATURE Signatures[1000];
UINT32 ChunkHead;
UINT32 ChunkTail;
XCRUSH_CHUNK Chunks[65534];
UINT16 NextChunks[65536];
UINT32 OriginalMatchCount;
UINT32 OptimizedMatchCount;
XCRUSH_MATCH_INFO OriginalMatches[1000];
XCRUSH_MATCH_INFO OptimizedMatches[1000];
};
#ifdef DEBUG_XCRUSH
static const char* xcrush_get_level_2_compression_flags_string(UINT32 flags)
{
flags &= 0xE0;
if (flags == 0)
return "PACKET_UNCOMPRESSED";
else if (flags == PACKET_COMPRESSED)
return "PACKET_COMPRESSED";
else if (flags == PACKET_AT_FRONT)
return "PACKET_AT_FRONT";
else if (flags == PACKET_FLUSHED)
return "PACKET_FLUSHED";
else if (flags == (PACKET_COMPRESSED | PACKET_AT_FRONT))
return "PACKET_COMPRESSED | PACKET_AT_FRONT";
else if (flags == (PACKET_COMPRESSED | PACKET_FLUSHED))
return "PACKET_COMPRESSED | PACKET_FLUSHED";
else if (flags == (PACKET_AT_FRONT | PACKET_FLUSHED))
return "PACKET_AT_FRONT | PACKET_FLUSHED";
else if (flags == (PACKET_COMPRESSED | PACKET_AT_FRONT | PACKET_FLUSHED))
return "PACKET_COMPRESSED | PACKET_AT_FRONT | PACKET_FLUSHED";
return "PACKET_UNKNOWN";
}
static const char* xcrush_get_level_1_compression_flags_string(UINT32 flags)
{
flags &= 0x17;
if (flags == 0)
return "L1_UNKNOWN";
else if (flags == L1_PACKET_AT_FRONT)
return "L1_PACKET_AT_FRONT";
else if (flags == L1_NO_COMPRESSION)
return "L1_NO_COMPRESSION";
else if (flags == L1_COMPRESSED)
return "L1_COMPRESSED";
else if (flags == L1_INNER_COMPRESSION)
return "L1_INNER_COMPRESSION";
else if (flags == (L1_PACKET_AT_FRONT | L1_NO_COMPRESSION))
return "L1_PACKET_AT_FRONT | L1_NO_COMPRESSION";
else if (flags == (L1_PACKET_AT_FRONT | L1_COMPRESSED))
return "L1_PACKET_AT_FRONT | L1_COMPRESSED";
else if (flags == (L1_PACKET_AT_FRONT | L1_INNER_COMPRESSION))
return "L1_PACKET_AT_FRONT | L1_INNER_COMPRESSION";
else if (flags == (L1_NO_COMPRESSION | L1_COMPRESSED))
return "L1_NO_COMPRESSION | L1_COMPRESSED";
else if (flags == (L1_NO_COMPRESSION | L1_INNER_COMPRESSION))
return "L1_NO_COMPRESSION | L1_INNER_COMPRESSION";
else if (flags == (L1_COMPRESSED | L1_INNER_COMPRESSION))
return "L1_COMPRESSED | L1_INNER_COMPRESSION";
else if (flags == (L1_NO_COMPRESSION | L1_COMPRESSED | L1_INNER_COMPRESSION))
return "L1_NO_COMPRESSION | L1_COMPRESSED | L1_INNER_COMPRESSION";
else if (flags == (L1_PACKET_AT_FRONT | L1_COMPRESSED | L1_INNER_COMPRESSION))
return "L1_PACKET_AT_FRONT | L1_COMPRESSED | L1_INNER_COMPRESSION";
else if (flags == (L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_INNER_COMPRESSION))
return "L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_INNER_COMPRESSION";
else if (flags == (L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_COMPRESSED))
return "L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_COMPRESSED";
else if (flags ==
(L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_COMPRESSED | L1_INNER_COMPRESSION))
return "L1_PACKET_AT_FRONT | L1_NO_COMPRESSION | L1_COMPRESSED | L1_INNER_COMPRESSION";
return "L1_UNKNOWN";
}
#endif
static UINT32 xcrush_update_hash(const BYTE* data, UINT32 size)
{
const BYTE* end;
UINT32 seed = 5381; /* same value as in djb2 */
if (size > 32)
{
size = 32;
seed = 5413;
}
end = &data[size - 4];
while (data < end)
{
seed += (data[3] ^ data[0]) + (data[1] << 8);
data += 4;
}
return (UINT16)seed;
}
static int xcrush_append_chunk(XCRUSH_CONTEXT* xcrush, const BYTE* data, UINT32* beg, UINT32 end)
{
UINT16 seed;
UINT32 size;
if (xcrush->SignatureIndex >= xcrush->SignatureCount)
return 0;
size = end - *beg;
if (size > 65535)
return 0;
if (size >= 15)
{
seed = xcrush_update_hash(&data[*beg], (UINT16)size);
xcrush->Signatures[xcrush->SignatureIndex].size = size;
xcrush->Signatures[xcrush->SignatureIndex].seed = seed;
xcrush->SignatureIndex++;
*beg = end;
}
return 1;
}
static int xcrush_compute_chunks(XCRUSH_CONTEXT* xcrush, const BYTE* data, UINT32 size,
UINT32* pIndex)
{
UINT32 i = 0;
UINT32 offset = 0;
UINT32 rotation = 0;
UINT32 accumulator = 0;
*pIndex = 0;
xcrush->SignatureIndex = 0;
if (size < 128)
return 0;
for (i = 0; i < 32; i++)
{
rotation = _rotl(accumulator, 1);
accumulator = data[i] ^ rotation;
}
for (i = 0; i < size - 64; i++)
{
rotation = _rotl(accumulator, 1);
accumulator = data[i + 32] ^ data[i] ^ rotation;
if (!(accumulator & 0x7F))
{
if (!xcrush_append_chunk(xcrush, data, &offset, i + 32))
return 0;
}
i++;
rotation = _rotl(accumulator, 1);
accumulator = data[i + 32] ^ data[i] ^ rotation;
if (!(accumulator & 0x7F))
{
if (!xcrush_append_chunk(xcrush, data, &offset, i + 32))
return 0;
}
i++;
rotation = _rotl(accumulator, 1);
accumulator = data[i + 32] ^ data[i] ^ rotation;
if (!(accumulator & 0x7F))
{
if (!xcrush_append_chunk(xcrush, data, &offset, i + 32))
return 0;
}
i++;
rotation = _rotl(accumulator, 1);
accumulator = data[i + 32] ^ data[i] ^ rotation;
if (!(accumulator & 0x7F))
{
if (!xcrush_append_chunk(xcrush, data, &offset, i + 32))
return 0;
}
}
if ((size == offset) || xcrush_append_chunk(xcrush, data, &offset, size))
{
*pIndex = xcrush->SignatureIndex;
return 1;
}
return 0;
}
static UINT32 xcrush_compute_signatures(XCRUSH_CONTEXT* xcrush, const BYTE* data, UINT32 size)
{
UINT32 index = 0;
if (xcrush_compute_chunks(xcrush, data, size, &index))
return index;
return 0;
}
static void xcrush_clear_hash_table_range(XCRUSH_CONTEXT* xcrush, UINT32 beg, UINT32 end)
{
UINT32 index;
for (index = 0; index < 65536; index++)
{
if (xcrush->NextChunks[index] >= beg)
{
if (xcrush->NextChunks[index] <= end)
{
xcrush->NextChunks[index] = 0;
}
}
}
for (index = 0; index < 65534; index++)
{
if (xcrush->Chunks[index].next >= beg)
{
if (xcrush->Chunks[index].next <= end)
{
xcrush->Chunks[index].next = 0;
}
}
}
}
static int xcrush_find_next_matching_chunk(XCRUSH_CONTEXT* xcrush, XCRUSH_CHUNK* chunk,
XCRUSH_CHUNK** pNextChunk)
{
UINT32 index;
XCRUSH_CHUNK* next = NULL;
if (!chunk)
return -4001; /* error */
if (chunk->next)
{
index = (chunk - xcrush->Chunks) / sizeof(XCRUSH_CHUNK);
if (index >= 65534)
return -4002; /* error */
if ((index < xcrush->ChunkHead) || (chunk->next >= xcrush->ChunkHead))
{
if (chunk->next >= 65534)
return -4003; /* error */
next = &xcrush->Chunks[chunk->next];
}
}
*pNextChunk = next;
return 1;
}
static int xcrush_insert_chunk(XCRUSH_CONTEXT* xcrush, XCRUSH_SIGNATURE* signature, UINT32 offset,
XCRUSH_CHUNK** pPrevChunk)
{
UINT32 seed;
UINT32 index;
if (xcrush->ChunkHead >= 65530)
{
xcrush->ChunkHead = 1;
xcrush->ChunkTail = 1;
}
if (xcrush->ChunkHead >= xcrush->ChunkTail)
{
xcrush_clear_hash_table_range(xcrush, xcrush->ChunkTail, xcrush->ChunkTail + 10000);
xcrush->ChunkTail += 10000;
}
index = xcrush->ChunkHead++;
if (xcrush->ChunkHead >= 65534)
return -3001; /* error */
xcrush->Chunks[index].offset = offset;
seed = signature->seed;
if (seed >= 65536)
return -3002; /* error */
if (xcrush->NextChunks[seed])
{
if (xcrush->NextChunks[seed] >= 65534)
return -3003; /* error */
*pPrevChunk = &xcrush->Chunks[xcrush->NextChunks[seed]];
}
xcrush->Chunks[index].next = xcrush->NextChunks[seed] & 0xFFFF;
xcrush->NextChunks[seed] = index;
return 1;
}
static int xcrush_find_match_length(XCRUSH_CONTEXT* xcrush, UINT32 MatchOffset, UINT32 ChunkOffset,
UINT32 HistoryOffset, UINT32 SrcSize, UINT32 MaxMatchLength,
XCRUSH_MATCH_INFO* MatchInfo)
{
UINT32 MatchSymbol;
UINT32 ChunkSymbol;
BYTE* ChunkBuffer;
BYTE* MatchBuffer;
BYTE* MatchStartPtr;
BYTE* ForwardChunkPtr;
BYTE* ReverseChunkPtr;
BYTE* ForwardMatchPtr;
BYTE* ReverseMatchPtr;
BYTE* HistoryBufferEnd;
UINT32 ReverseMatchLength;
UINT32 ForwardMatchLength;
UINT32 TotalMatchLength;
BYTE* HistoryBuffer;
UINT32 HistoryBufferSize;
ForwardMatchLength = 0;
ReverseMatchLength = 0;
HistoryBuffer = xcrush->HistoryBuffer;
HistoryBufferSize = xcrush->HistoryBufferSize;
HistoryBufferEnd = &HistoryBuffer[HistoryOffset + SrcSize];
if (MatchOffset > HistoryBufferSize)
return -2001; /* error */
MatchBuffer = &HistoryBuffer[MatchOffset];
if (ChunkOffset > HistoryBufferSize)
return -2002; /* error */
ChunkBuffer = &HistoryBuffer[ChunkOffset];
if (MatchOffset == ChunkOffset)
return -2003; /* error */
if (MatchBuffer < HistoryBuffer)
return -2004; /* error */
if (ChunkBuffer < HistoryBuffer)
return -2005; /* error */
ForwardMatchPtr = &HistoryBuffer[MatchOffset];
ForwardChunkPtr = &HistoryBuffer[ChunkOffset];
if ((&MatchBuffer[MaxMatchLength + 1] < HistoryBufferEnd) &&
(MatchBuffer[MaxMatchLength + 1] != ChunkBuffer[MaxMatchLength + 1]))
{
return 0;
}
while (1)
{
MatchSymbol = *ForwardMatchPtr++;
ChunkSymbol = *ForwardChunkPtr++;
if (MatchSymbol != ChunkSymbol)
break;
if (ForwardMatchPtr > HistoryBufferEnd)
break;
ForwardMatchLength++;
}
ReverseMatchPtr = MatchBuffer - 1;
ReverseChunkPtr = ChunkBuffer - 1;
while ((ReverseMatchPtr > &HistoryBuffer[HistoryOffset]) && (ReverseChunkPtr > HistoryBuffer) &&
(*ReverseMatchPtr == *ReverseChunkPtr))
{
ReverseMatchLength++;
ReverseMatchPtr--;
ReverseChunkPtr--;
}
MatchStartPtr = MatchBuffer - ReverseMatchLength;
TotalMatchLength = ReverseMatchLength + ForwardMatchLength;
if (TotalMatchLength < 11)
return 0;
if (MatchStartPtr < HistoryBuffer)
return -2006; /* error */
MatchInfo->MatchOffset = MatchStartPtr - HistoryBuffer;
MatchInfo->ChunkOffset = ChunkBuffer - ReverseMatchLength - HistoryBuffer;
MatchInfo->MatchLength = TotalMatchLength;
return (int)TotalMatchLength;
}
static int xcrush_find_all_matches(XCRUSH_CONTEXT* xcrush, UINT32 SignatureIndex,
UINT32 HistoryOffset, UINT32 SrcOffset, UINT32 SrcSize)
{
UINT32 i = 0;
UINT32 j = 0;
int status = 0;
UINT32 offset = 0;
UINT32 ChunkIndex = 0;
UINT32 ChunkCount = 0;
XCRUSH_CHUNK* chunk = NULL;
UINT32 MatchLength = 0;
UINT32 MaxMatchLength = 0;
UINT32 PrevMatchEnd = 0;
XCRUSH_MATCH_INFO MatchInfo = { 0 };
XCRUSH_MATCH_INFO MaxMatchInfo = { 0 };
XCRUSH_SIGNATURE* Signatures = NULL;
Signatures = xcrush->Signatures;
for (i = 0; i < SignatureIndex; i++)
{
offset = SrcOffset + HistoryOffset;
if (!Signatures[i].size)
return -1001; /* error */
status = xcrush_insert_chunk(xcrush, &Signatures[i], offset, &chunk);
if (status < 0)
return status;
if (chunk && (SrcOffset + HistoryOffset + Signatures[i].size >= PrevMatchEnd))
{
ChunkCount = 0;
MaxMatchLength = 0;
ZeroMemory(&MaxMatchInfo, sizeof(XCRUSH_MATCH_INFO));
while (chunk)
{
if ((chunk->offset < HistoryOffset) || (chunk->offset < offset) ||
(chunk->offset > SrcSize + HistoryOffset))
{
status = xcrush_find_match_length(xcrush, offset, chunk->offset, HistoryOffset,
SrcSize, MaxMatchLength, &MatchInfo);
if (status < 0)
return status; /* error */
MatchLength = (UINT32)status;
if (MatchLength > MaxMatchLength)
{
MaxMatchLength = MatchLength;
MaxMatchInfo.MatchOffset = MatchInfo.MatchOffset;
MaxMatchInfo.ChunkOffset = MatchInfo.ChunkOffset;
MaxMatchInfo.MatchLength = MatchInfo.MatchLength;
if (MatchLength > 256)
break;
}
}
ChunkIndex = ChunkCount++;
if (ChunkIndex > 4)
break;
status = xcrush_find_next_matching_chunk(xcrush, chunk, &chunk);
if (status < 0)
return status; /* error */
}
if (MaxMatchLength)
{
xcrush->OriginalMatches[j].MatchOffset = MaxMatchInfo.MatchOffset;
xcrush->OriginalMatches[j].ChunkOffset = MaxMatchInfo.ChunkOffset;
xcrush->OriginalMatches[j].MatchLength = MaxMatchInfo.MatchLength;
if (xcrush->OriginalMatches[j].MatchOffset < HistoryOffset)
return -1002; /* error */
PrevMatchEnd =
xcrush->OriginalMatches[j].MatchLength + xcrush->OriginalMatches[j].MatchOffset;
j++;
if (j >= 1000)
return -1003; /* error */
}
}
SrcOffset += Signatures[i].size;
if (SrcOffset > SrcSize)
return -1004; /* error */
}
if (SrcOffset > SrcSize)
return -1005; /* error */
return (int)j;
}
static int xcrush_optimize_matches(XCRUSH_CONTEXT* xcrush)
{
UINT32 i, j;
UINT32 MatchDiff;
UINT32 PrevMatchEnd;
UINT32 TotalMatchLength;
UINT32 OriginalMatchCount;
UINT32 OptimizedMatchCount;
XCRUSH_MATCH_INFO* OriginalMatch;
XCRUSH_MATCH_INFO* OptimizedMatch;
XCRUSH_MATCH_INFO* OriginalMatches;
XCRUSH_MATCH_INFO* OptimizedMatches;
j = 0;
PrevMatchEnd = 0;
TotalMatchLength = 0;
OriginalMatches = xcrush->OriginalMatches;
OriginalMatchCount = xcrush->OriginalMatchCount;
OptimizedMatches = xcrush->OptimizedMatches;
for (i = 0; i < OriginalMatchCount; i++)
{
if (OriginalMatches[i].MatchOffset <= PrevMatchEnd)
{
if ((OriginalMatches[i].MatchOffset < PrevMatchEnd) &&
(OriginalMatches[i].MatchLength + OriginalMatches[i].MatchOffset >
PrevMatchEnd + 6))
{
MatchDiff = PrevMatchEnd - OriginalMatches[i].MatchOffset;
OriginalMatch = &OriginalMatches[i];
OptimizedMatch = &OptimizedMatches[j];
OptimizedMatch->MatchOffset = OriginalMatch->MatchOffset;
OptimizedMatch->ChunkOffset = OriginalMatch->ChunkOffset;
OptimizedMatch->MatchLength = OriginalMatch->MatchLength;
if (OptimizedMatches[j].MatchLength <= MatchDiff)
return -5001; /* error */
if (MatchDiff >= 20000)
return -5002; /* error */
OptimizedMatches[j].MatchLength -= MatchDiff;
OptimizedMatches[j].MatchOffset += MatchDiff;
OptimizedMatches[j].ChunkOffset += MatchDiff;
PrevMatchEnd = OptimizedMatches[j].MatchLength + OptimizedMatches[j].MatchOffset;
TotalMatchLength += OptimizedMatches[j].MatchLength;
j++;
}
}
else
{
OriginalMatch = &OriginalMatches[i];
OptimizedMatch = &OptimizedMatches[j];
OptimizedMatch->MatchOffset = OriginalMatch->MatchOffset;
OptimizedMatch->ChunkOffset = OriginalMatch->ChunkOffset;
OptimizedMatch->MatchLength = OriginalMatch->MatchLength;
PrevMatchEnd = OptimizedMatches[j].MatchLength + OptimizedMatches[j].MatchOffset;
TotalMatchLength += OptimizedMatches[j].MatchLength;
j++;
}
}
OptimizedMatchCount = j;
xcrush->OptimizedMatchCount = OptimizedMatchCount;
return (int)TotalMatchLength;
}
static int xcrush_generate_output(XCRUSH_CONTEXT* xcrush, BYTE* OutputBuffer, UINT32 OutputSize,
UINT32 HistoryOffset, UINT32* pDstSize)
{
BYTE* Literals;
BYTE* OutputEnd;
UINT32 MatchIndex;
UINT32 MatchOffset;
UINT16 MatchLength;
UINT32 MatchCount;
UINT32 CurrentOffset;
UINT32 MatchOffsetDiff;
UINT32 HistoryOffsetDiff;
RDP61_MATCH_DETAILS* MatchDetails;
MatchCount = xcrush->OptimizedMatchCount;
OutputEnd = &OutputBuffer[OutputSize];
if (&OutputBuffer[2] >= &OutputBuffer[OutputSize])
return -6001; /* error */
*((UINT16*)OutputBuffer) = MatchCount;
MatchDetails = (RDP61_MATCH_DETAILS*)&OutputBuffer[2];
Literals = (BYTE*)&MatchDetails[MatchCount];
if (Literals > OutputEnd)
return -6002; /* error */
for (MatchIndex = 0; MatchIndex < MatchCount; MatchIndex++)
{
MatchDetails[MatchIndex].MatchLength =
(UINT16)(xcrush->OptimizedMatches[MatchIndex].MatchLength);
MatchDetails[MatchIndex].MatchOutputOffset =
(UINT16)(xcrush->OptimizedMatches[MatchIndex].MatchOffset - HistoryOffset);
MatchDetails[MatchIndex].MatchHistoryOffset =
xcrush->OptimizedMatches[MatchIndex].ChunkOffset;
}
CurrentOffset = HistoryOffset;
for (MatchIndex = 0; MatchIndex < MatchCount; MatchIndex++)
{
MatchLength = (UINT16)(xcrush->OptimizedMatches[MatchIndex].MatchLength);
MatchOffset = xcrush->OptimizedMatches[MatchIndex].MatchOffset;
if (MatchOffset <= CurrentOffset)
{
if (MatchOffset != CurrentOffset)
return -6003; /* error */
CurrentOffset = MatchOffset + MatchLength;
}
else
{
MatchOffsetDiff = MatchOffset - CurrentOffset;
if (Literals + MatchOffset - CurrentOffset >= OutputEnd)
return -6004; /* error */
CopyMemory(Literals, &xcrush->HistoryBuffer[CurrentOffset], MatchOffsetDiff);
if (Literals >= OutputEnd)
return -6005; /* error */
Literals += MatchOffsetDiff;
CurrentOffset = MatchOffset + MatchLength;
}
}
HistoryOffsetDiff = xcrush->HistoryOffset - CurrentOffset;
if (Literals + HistoryOffsetDiff >= OutputEnd)
return -6006; /* error */
CopyMemory(Literals, &xcrush->HistoryBuffer[CurrentOffset], HistoryOffsetDiff);
*pDstSize = Literals + HistoryOffsetDiff - OutputBuffer;
return 1;
}
static INLINE size_t xcrush_copy_bytes(BYTE* dst, const BYTE* src, size_t num)
{
size_t diff, rest, end, a;
if (src + num < dst || src > dst + num)
{
memcpy(dst, src, num);
}
else
{
// src and dst overlaps
// we should copy the area that doesn't overlap repeatly
diff = (dst > src) ? dst - src : src - dst;
rest = num % diff;
end = num - rest;
for (a = 0; a < end; a += diff)
{
memcpy(&dst[a], &src[a], diff);
}
if (rest != 0)
memcpy(&dst[end], &src[end], rest);
}
return num;
}
static int xcrush_decompress_l1(XCRUSH_CONTEXT* xcrush, const BYTE* pSrcData, UINT32 SrcSize,
BYTE** ppDstData, UINT32* pDstSize, UINT32 flags)
{
const BYTE* pSrcEnd = NULL;
const BYTE* Literals = NULL;
UINT16 MatchCount = 0;
UINT16 MatchIndex = 0;
BYTE* OutputPtr = NULL;
size_t OutputLength = 0;
UINT32 OutputOffset = 0;
BYTE* HistoryPtr = NULL;
BYTE* HistoryBuffer = NULL;
BYTE* HistoryBufferEnd = NULL;
UINT32 HistoryBufferSize = 0;
UINT16 MatchLength = 0;
UINT16 MatchOutputOffset = 0;
UINT32 MatchHistoryOffset = 0;
RDP61_MATCH_DETAILS* MatchDetails = NULL;
if (SrcSize < 1)
return -1001;
if (flags & L1_PACKET_AT_FRONT)
xcrush->HistoryOffset = 0;
pSrcEnd = &pSrcData[SrcSize];
HistoryBuffer = xcrush->HistoryBuffer;
HistoryBufferSize = xcrush->HistoryBufferSize;
HistoryBufferEnd = &(HistoryBuffer[HistoryBufferSize]);
xcrush->HistoryPtr = HistoryPtr = &(HistoryBuffer[xcrush->HistoryOffset]);
if (flags & L1_NO_COMPRESSION)
{
Literals = pSrcData;
}
else
{
if (!(flags & L1_COMPRESSED))
return -1002;
if ((pSrcData + 2) > pSrcEnd)
return -1003;
Data_Read_UINT16(pSrcData, MatchCount);
MatchDetails = (RDP61_MATCH_DETAILS*)&pSrcData[2];
Literals = (BYTE*)&MatchDetails[MatchCount];
OutputOffset = 0;
if (Literals > pSrcEnd)
return -1004;
for (MatchIndex = 0; MatchIndex < MatchCount; MatchIndex++)
{
Data_Read_UINT16(&MatchDetails[MatchIndex].MatchLength, MatchLength);
Data_Read_UINT16(&MatchDetails[MatchIndex].MatchOutputOffset, MatchOutputOffset);
Data_Read_UINT32(&MatchDetails[MatchIndex].MatchHistoryOffset, MatchHistoryOffset);
if (MatchOutputOffset < OutputOffset)
return -1005;
if (MatchLength > HistoryBufferSize)
return -1006;
if (MatchHistoryOffset > HistoryBufferSize)
return -1007;
OutputLength = MatchOutputOffset - OutputOffset;
if ((MatchOutputOffset - OutputOffset) > HistoryBufferSize)
return -1008;
if (OutputLength > 0)
{
if ((&HistoryPtr[OutputLength] >= HistoryBufferEnd) || (Literals >= pSrcEnd) ||
(&Literals[OutputLength] > pSrcEnd))
return -1009;
xcrush_copy_bytes(HistoryPtr, Literals, OutputLength);
HistoryPtr += OutputLength;
Literals += OutputLength;
OutputOffset += OutputLength;
if (Literals > pSrcEnd)
return -1010;
}
OutputPtr = &xcrush->HistoryBuffer[MatchHistoryOffset];
if ((&HistoryPtr[MatchLength] >= HistoryBufferEnd) ||
(&OutputPtr[MatchLength] >= HistoryBufferEnd))
return -1011;
xcrush_copy_bytes(HistoryPtr, OutputPtr, MatchLength);
OutputOffset += MatchLength;
HistoryPtr += MatchLength;
}
}
if (Literals < pSrcEnd)
{
OutputLength = pSrcEnd - Literals;
if ((&HistoryPtr[OutputLength] >= HistoryBufferEnd) || (&Literals[OutputLength] > pSrcEnd))
return -1012;
xcrush_copy_bytes(HistoryPtr, Literals, OutputLength);
HistoryPtr += OutputLength;
}
xcrush->HistoryOffset = HistoryPtr - HistoryBuffer;
*pDstSize = HistoryPtr - xcrush->HistoryPtr;
*ppDstData = xcrush->HistoryPtr;
return 1;
}
int xcrush_decompress(XCRUSH_CONTEXT* xcrush, BYTE* pSrcData, UINT32 SrcSize, BYTE** ppDstData,
UINT32* pDstSize, UINT32 flags)
{
int status = 0;
UINT32 DstSize = 0;
BYTE* pDstData = NULL;
BYTE Level1ComprFlags;
BYTE Level2ComprFlags;
if (SrcSize < 2)
return -1;
Level1ComprFlags = pSrcData[0];
Level2ComprFlags = pSrcData[1];
pSrcData += 2;
SrcSize -= 2;
if (flags & PACKET_FLUSHED)
{
ZeroMemory(xcrush->HistoryBuffer, xcrush->HistoryBufferSize);
xcrush->HistoryOffset = 0;
}
if (!(Level2ComprFlags & PACKET_COMPRESSED))
{
status =
xcrush_decompress_l1(xcrush, pSrcData, SrcSize, ppDstData, pDstSize, Level1ComprFlags);
return status;
}
status =
mppc_decompress(xcrush->mppc, pSrcData, SrcSize, &pDstData, &DstSize, Level2ComprFlags);
if (status < 0)
return status;
status = xcrush_decompress_l1(xcrush, pDstData, DstSize, ppDstData, pDstSize, Level1ComprFlags);
return status;
}
static int xcrush_compress_l1(XCRUSH_CONTEXT* xcrush, const BYTE* pSrcData, UINT32 SrcSize,
BYTE** ppDstData, UINT32* pDstSize, UINT32* pFlags)
{
int status = 0;
UINT32 Flags = 0;
UINT32 HistoryOffset = 0;
BYTE* HistoryPtr = NULL;
BYTE* HistoryBuffer = NULL;
UINT32 SignatureIndex = 0;
if (xcrush->HistoryOffset + SrcSize + 8 > xcrush->HistoryBufferSize)
{
xcrush->HistoryOffset = 0;
Flags |= L1_PACKET_AT_FRONT;
}
HistoryOffset = xcrush->HistoryOffset;
HistoryBuffer = xcrush->HistoryBuffer;
HistoryPtr = &HistoryBuffer[HistoryOffset];
MoveMemory(HistoryPtr, pSrcData, SrcSize);
xcrush->HistoryOffset += SrcSize;
if (SrcSize > 50)
{
SignatureIndex = xcrush_compute_signatures(xcrush, pSrcData, SrcSize);
if (SignatureIndex)
{
status = xcrush_find_all_matches(xcrush, SignatureIndex, HistoryOffset, 0, SrcSize);
if (status < 0)
return status;
xcrush->OriginalMatchCount = (UINT32)status;
xcrush->OptimizedMatchCount = 0;
if (xcrush->OriginalMatchCount)
{
status = xcrush_optimize_matches(xcrush);
if (status < 0)
return status;
}
if (xcrush->OptimizedMatchCount)
{
status =
xcrush_generate_output(xcrush, *ppDstData, SrcSize, HistoryOffset, pDstSize);
if (status < 0)
return status;
Flags |= L1_COMPRESSED;
}
}
}
if (!(Flags & L1_COMPRESSED))
{
Flags |= L1_NO_COMPRESSION;
*pDstSize = SrcSize;
}
*pFlags = Flags;
return 1;
}
int xcrush_compress(XCRUSH_CONTEXT* xcrush, BYTE* pSrcData, UINT32 SrcSize, BYTE** ppDstData,
UINT32* pDstSize, UINT32* pFlags)
{
int status = 0;
UINT32 DstSize = 0;
BYTE* pDstData = NULL;
BYTE* CompressedData = NULL;
UINT32 CompressedDataSize = 0;
BYTE* OriginalData = NULL;
UINT32 OriginalDataSize = 0;
UINT32 Level1ComprFlags = 0;
UINT32 Level2ComprFlags = 0;
UINT32 CompressionLevel = 3;
if (SrcSize > 16384)
return -1001;
if ((SrcSize + 2) > *pDstSize)
return -1002;
OriginalData = *ppDstData;
OriginalDataSize = SrcSize;
pDstData = xcrush->BlockBuffer;
CompressedDataSize = SrcSize;
status = xcrush_compress_l1(xcrush, pSrcData, SrcSize, &pDstData, &CompressedDataSize,
&Level1ComprFlags);
if (status < 0)
return status;
if (Level1ComprFlags & L1_COMPRESSED)
{
CompressedData = pDstData;
if (CompressedDataSize > SrcSize)
return -1003;
}
else
{
CompressedData = pSrcData;
if (CompressedDataSize != SrcSize)
return -1004;
}
status = 0;
pDstData = &OriginalData[2];
DstSize = OriginalDataSize - 2;
if (CompressedDataSize > 50)
{
status = mppc_compress(xcrush->mppc, CompressedData, CompressedDataSize, &pDstData,
&DstSize, &Level2ComprFlags);
}
if (status < 0)
return status;
if (!status || (Level2ComprFlags & PACKET_FLUSHED))
{
if (CompressedDataSize > DstSize)
{
xcrush_context_reset(xcrush, TRUE);
*ppDstData = pSrcData;
*pDstSize = SrcSize;
*pFlags = 0;
return 1;
}
DstSize = CompressedDataSize;
CopyMemory(&OriginalData[2], CompressedData, CompressedDataSize);
}
if (Level2ComprFlags & PACKET_COMPRESSED)
{
Level2ComprFlags |= xcrush->CompressionFlags;
xcrush->CompressionFlags = 0;
}
else if (Level2ComprFlags & PACKET_FLUSHED)
{
xcrush->CompressionFlags = PACKET_FLUSHED;
}
Level1ComprFlags |= L1_INNER_COMPRESSION;
OriginalData[0] = (BYTE)Level1ComprFlags;
OriginalData[1] = (BYTE)Level2ComprFlags;
#if DEBUG_XCRUSH
WLog_DBG(TAG, "XCrushCompress: Level1ComprFlags: %s Level2ComprFlags: %s",
xcrush_get_level_1_compression_flags_string(Level1ComprFlags),
xcrush_get_level_2_compression_flags_string(Level2ComprFlags));
#endif
if (*pDstSize < (DstSize + 2))
return -1006;
*pDstSize = DstSize + 2;
*pFlags = PACKET_COMPRESSED | CompressionLevel;
return 1;
}
void xcrush_context_reset(XCRUSH_CONTEXT* xcrush, BOOL flush)
{
xcrush->SignatureIndex = 0;
xcrush->SignatureCount = 1000;
ZeroMemory(&(xcrush->Signatures), sizeof(XCRUSH_SIGNATURE) * xcrush->SignatureCount);
xcrush->CompressionFlags = 0;
xcrush->ChunkHead = xcrush->ChunkTail = 1;
ZeroMemory(&(xcrush->Chunks), sizeof(xcrush->Chunks));
ZeroMemory(&(xcrush->NextChunks), sizeof(xcrush->NextChunks));
ZeroMemory(&(xcrush->OriginalMatches), sizeof(xcrush->OriginalMatches));
ZeroMemory(&(xcrush->OptimizedMatches), sizeof(xcrush->OptimizedMatches));
if (flush)
xcrush->HistoryOffset = xcrush->HistoryBufferSize + 1;
else
xcrush->HistoryOffset = 0;
mppc_context_reset(xcrush->mppc, flush);
}
XCRUSH_CONTEXT* xcrush_context_new(BOOL Compressor)
{
XCRUSH_CONTEXT* xcrush;
xcrush = (XCRUSH_CONTEXT*)calloc(1, sizeof(XCRUSH_CONTEXT));
if (xcrush)
{
xcrush->Compressor = Compressor;
xcrush->mppc = mppc_context_new(1, Compressor);
xcrush->HistoryOffset = 0;
xcrush->HistoryBufferSize = 2000000;
xcrush_context_reset(xcrush, FALSE);
}
return xcrush;
}
void xcrush_context_free(XCRUSH_CONTEXT* xcrush)
{
if (xcrush)
{
mppc_context_free(xcrush->mppc);
free(xcrush);
}
}