我正在尝试创建一个函数,用于解压缩
以下是压缩函数:
我正在使用从这里下载的
LZAM2
压缩数据。我受到了这个教程的启发:(链接),它对于 LZMA
工作得非常好,我试图将其适应于 LZMA2
。我已经成功地创建了 LZMA2
的压缩函数,但是对于解压缩函数却没有成功。以下是压缩函数:
static void Compress2Inc(std::vector<unsigned char> &outBuf,
const std::vector<unsigned char> &inBuf)
{
CLzma2EncHandle enc = Lzma2Enc_Create(&SzAllocForLzma, &SzAllocForLzma2);
assert(enc);
CLzma2EncProps props;
Lzma2EncProps_Init(&props);
props.lzmaProps.writeEndMark = 1; // 0 or 1
SRes res = Lzma2Enc_SetProps(enc, &props);
assert(res == SZ_OK);
unsigned propsSize = LZMA_PROPS_SIZE;
outBuf.resize(propsSize);
res = Lzma2Enc_WriteProperties(enc);
//cout << res;
//assert(res == SZ_OK && propsSize == LZMA_PROPS_SIZE);
VectorInStream inStream = { &VectorInStream_Read, &inBuf, 0 };
VectorOutStream outStream = { &VectorOutStream_Write, &outBuf };
res = Lzma2Enc_Encode(enc,
(ISeqOutStream*)&outStream, (ISeqInStream*)&inStream,
0);
assert(res == SZ_OK);
Lzma2Enc_Destroy(enc);
}
在哪里:
static void *AllocForLzma2(void *, size_t size) { return BigAlloc(size); }
static void FreeForLzma2(void *, void *address) { BigFree(address); }
static ISzAlloc SzAllocForLzma2 = { AllocForLzma2, FreeForLzma2 };
static void *AllocForLzma(void *, size_t size) { return MyAlloc(size); }
static void FreeForLzma(void *, void *address) { MyFree(address); }
static ISzAlloc SzAllocForLzma = { AllocForLzma, FreeForLzma };
typedef struct
{
ISeqInStream SeqInStream;
const std::vector<unsigned char> *Buf;
unsigned BufPos;
} VectorInStream;
SRes VectorInStream_Read(void *p, void *buf, size_t *size)
{
VectorInStream *ctx = (VectorInStream*)p;
*size = min(*size, ctx->Buf->size() - ctx->BufPos);
if (*size)
memcpy(buf, &(*ctx->Buf)[ctx->BufPos], *size);
ctx->BufPos += *size;
return SZ_OK;
}
typedef struct
{
ISeqOutStream SeqOutStream;
std::vector<unsigned char> *Buf;
} VectorOutStream;
size_t VectorOutStream_Write(void *p, const void *buf, size_t size)
{
VectorOutStream *ctx = (VectorOutStream*)p;
if (size)
{
unsigned oldSize = ctx->Buf->size();
ctx->Buf->resize(oldSize + size);
memcpy(&(*ctx->Buf)[oldSize], buf, size);
}
return size;
}
这是目前我写的解压函数,但是Lzma2Dec_DecodeToBuf
函数返回错误码1
(SZ_ERROR_DATA
),我在网上没有找到任何有关此问题的信息。
static void Uncompress2Inc(std::vector<unsigned char> &outBuf,
const std::vector<unsigned char> &inBuf)
{
CLzma2Dec dec;
Lzma2Dec_Construct(&dec);
SRes res = Lzma2Dec_Allocate(&dec, outBuf.size(), &SzAllocForLzma);
assert(res == SZ_OK);
Lzma2Dec_Init(&dec);
outBuf.resize(UNCOMPRESSED_SIZE);
unsigned outPos = 0, inPos = LZMA_PROPS_SIZE;
ELzmaStatus status;
const unsigned BUF_SIZE = 10240;
while (outPos < outBuf.size())
{
unsigned destLen = min(BUF_SIZE, outBuf.size() - outPos);
unsigned srcLen = min(BUF_SIZE, inBuf.size() - inPos);
unsigned srcLenOld = srcLen, destLenOld = destLen;
res = Lzma2Dec_DecodeToBuf(&dec,
&outBuf[outPos], &destLen,
&inBuf[inPos], &srcLen,
(outPos + destLen == outBuf.size()) ? LZMA_FINISH_END : LZMA_FINISH_ANY,
&status);
assert(res == SZ_OK);
inPos += srcLen;
outPos += destLen;
if (status == LZMA_STATUS_FINISHED_WITH_MARK)
break;
}
Lzma2Dec_Free(&dec, &SzAllocForLzma);
outBuf.resize(outPos);
}
我正在使用从这里下载的
LZMA SDK
和Visual Studio 2008
。有人在这里遇到了完全相同的问题,但我无法运用他的代码...
有人曾经成功地使用LZMA SDK
解压缩LZMA2
压缩文件吗?
请帮忙!
p7zip
是7zip的GNU/Linux POSIX
版本。我需要在Windows
上使用它。 - Jacob Krieg