| /* Lzma86Enc.c -- LZMA + x86 (BCJ) Filter Encoder |
| 2008-08-05 |
| Igor Pavlov |
| Public domain */ |
| |
| #include <string.h> |
| |
| #include "Lzma86Enc.h" |
| |
| #include "../Alloc.h" |
| #include "../Bra.h" |
| #include "../LzmaEnc.h" |
| |
| #define SZE_OUT_OVERFLOW SZE_DATA_ERROR |
| |
| static void *SzAlloc(void *p, size_t size) { p = p; return MyAlloc(size); } |
| static void SzFree(void *p, void *address) { p = p; MyFree(address); } |
| static ISzAlloc g_Alloc = { SzAlloc, SzFree }; |
| |
| #define LZMA86_SIZE_OFFSET (1 + LZMA_PROPS_SIZE) |
| #define LZMA86_HEADER_SIZE (LZMA86_SIZE_OFFSET + 8) |
| |
| int Lzma86_Encode(Byte *dest, size_t *destLen, const Byte *src, size_t srcLen, |
| int level, UInt32 dictSize, int filterMode) |
| { |
| size_t outSize2 = *destLen; |
| Byte *filteredStream; |
| Bool useFilter; |
| int mainResult = SZ_ERROR_OUTPUT_EOF; |
| CLzmaEncProps props; |
| LzmaEncProps_Init(&props); |
| props.level = level; |
| props.dictSize = dictSize; |
| |
| *destLen = 0; |
| if (outSize2 < LZMA86_HEADER_SIZE) |
| return SZ_ERROR_OUTPUT_EOF; |
| |
| { |
| int i; |
| UInt64 t = srcLen; |
| for (i = 0; i < 8; i++, t >>= 8) |
| dest[LZMA86_SIZE_OFFSET + i] = (Byte)t; |
| } |
| |
| filteredStream = 0; |
| useFilter = (filterMode != SZ_FILTER_NO); |
| if (useFilter) |
| { |
| if (srcLen != 0) |
| { |
| filteredStream = (Byte *)MyAlloc(srcLen); |
| if (filteredStream == 0) |
| return SZ_ERROR_MEM; |
| memcpy(filteredStream, src, srcLen); |
| } |
| { |
| UInt32 x86State; |
| x86_Convert_Init(x86State); |
| x86_Convert(filteredStream, srcLen, 0, &x86State, 1); |
| } |
| } |
| |
| { |
| size_t minSize = 0; |
| Bool bestIsFiltered = False; |
| |
| /* passes for SZ_FILTER_AUTO: |
| 0 - BCJ + LZMA |
| 1 - LZMA |
| 2 - BCJ + LZMA agaian, if pass 0 (BCJ + LZMA) is better. |
| */ |
| int numPasses = (filterMode == SZ_FILTER_AUTO) ? 3 : 1; |
| |
| int i; |
| for (i = 0; i < numPasses; i++) |
| { |
| size_t outSizeProcessed = outSize2 - LZMA86_HEADER_SIZE; |
| size_t outPropsSize = 5; |
| SRes curRes; |
| Bool curModeIsFiltered = (numPasses > 1 && i == numPasses - 1); |
| if (curModeIsFiltered && !bestIsFiltered) |
| break; |
| if (useFilter && i == 0) |
| curModeIsFiltered = True; |
| |
| curRes = LzmaEncode(dest + LZMA86_HEADER_SIZE, &outSizeProcessed, |
| curModeIsFiltered ? filteredStream : src, srcLen, |
| &props, dest + 1, &outPropsSize, 0, |
| NULL, &g_Alloc, &g_Alloc); |
| |
| if (curRes != SZ_ERROR_OUTPUT_EOF) |
| { |
| if (curRes != SZ_OK) |
| { |
| mainResult = curRes; |
| break; |
| } |
| if (outSizeProcessed <= minSize || mainResult != SZ_OK) |
| { |
| minSize = outSizeProcessed; |
| bestIsFiltered = curModeIsFiltered; |
| mainResult = SZ_OK; |
| } |
| } |
| } |
| dest[0] = (bestIsFiltered ? 1 : 0); |
| *destLen = LZMA86_HEADER_SIZE + minSize; |
| } |
| if (useFilter) |
| MyFree(filteredStream); |
| return mainResult; |
| } |