p7zip-rar/C/XzDec.c
2017-10-11 12:40:22 +02:00

914 lines
22 KiB
C

/* XzDec.c -- Xz Decode
2015-11-09 : Igor Pavlov : Public domain */
#include "Precomp.h"
/* #define XZ_DUMP */
#ifdef XZ_DUMP
#include <stdio.h>
#endif
#include <stdlib.h>
#include <string.h>
#include "7zCrc.h"
#include "Alloc.h"
#include "Bra.h"
#include "CpuArch.h"
#include "Delta.h"
#include "Lzma2Dec.h"
#ifdef USE_SUBBLOCK
#include "Bcj3Dec.c"
#include "SbDec.c"
#endif
#include "Xz.h"
#define XZ_CHECK_SIZE_MAX 64
#define CODER_BUF_SIZE (1 << 17)
unsigned Xz_ReadVarInt(const Byte *p, size_t maxSize, UInt64 *value)
{
unsigned i, limit;
*value = 0;
limit = (maxSize > 9) ? 9 : (unsigned)maxSize;
for (i = 0; i < limit;)
{
Byte b = p[i];
*value |= (UInt64)(b & 0x7F) << (7 * i++);
if ((b & 0x80) == 0)
return (b == 0 && i != 1) ? 0 : i;
}
return 0;
}
/* ---------- BraState ---------- */
#define BRA_BUF_SIZE (1 << 14)
typedef struct
{
size_t bufPos;
size_t bufConv;
size_t bufTotal;
UInt32 methodId;
int encodeMode;
UInt32 delta;
UInt32 ip;
UInt32 x86State;
Byte deltaState[DELTA_STATE_SIZE];
Byte buf[BRA_BUF_SIZE];
} CBraState;
static void BraState_Free(void *pp, ISzAlloc *alloc)
{
alloc->Free(alloc, pp);
}
static SRes BraState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAlloc *alloc)
{
CBraState *p = ((CBraState *)pp);
UNUSED_VAR(alloc);
p->ip = 0;
if (p->methodId == XZ_ID_Delta)
{
if (propSize != 1)
return SZ_ERROR_UNSUPPORTED;
p->delta = (unsigned)props[0] + 1;
}
else
{
if (propSize == 4)
{
UInt32 v = GetUi32(props);
switch (p->methodId)
{
case XZ_ID_PPC:
case XZ_ID_ARM:
case XZ_ID_SPARC:
if ((v & 3) != 0)
return SZ_ERROR_UNSUPPORTED;
break;
case XZ_ID_ARMT:
if ((v & 1) != 0)
return SZ_ERROR_UNSUPPORTED;
break;
case XZ_ID_IA64:
if ((v & 0xF) != 0)
return SZ_ERROR_UNSUPPORTED;
break;
}
p->ip = v;
}
else if (propSize != 0)
return SZ_ERROR_UNSUPPORTED;
}
return SZ_OK;
}
static void BraState_Init(void *pp)
{
CBraState *p = ((CBraState *)pp);
p->bufPos = p->bufConv = p->bufTotal = 0;
x86_Convert_Init(p->x86State);
if (p->methodId == XZ_ID_Delta)
Delta_Init(p->deltaState);
}
#define CASE_BRA_CONV(isa) case XZ_ID_ ## isa: p->bufConv = isa ## _Convert(p->buf, p->bufTotal, p->ip, p->encodeMode); break;
static SRes BraState_Code(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
int srcWasFinished, ECoderFinishMode finishMode, int *wasFinished)
{
CBraState *p = ((CBraState *)pp);
SizeT destLenOrig = *destLen;
SizeT srcLenOrig = *srcLen;
UNUSED_VAR(finishMode);
*destLen = 0;
*srcLen = 0;
*wasFinished = 0;
while (destLenOrig > 0)
{
if (p->bufPos != p->bufConv)
{
size_t curSize = p->bufConv - p->bufPos;
if (curSize > destLenOrig)
curSize = destLenOrig;
memcpy(dest, p->buf + p->bufPos, curSize);
p->bufPos += curSize;
*destLen += curSize;
dest += curSize;
destLenOrig -= curSize;
continue;
}
p->bufTotal -= p->bufPos;
memmove(p->buf, p->buf + p->bufPos, p->bufTotal);
p->bufPos = 0;
p->bufConv = 0;
{
size_t curSize = BRA_BUF_SIZE - p->bufTotal;
if (curSize > srcLenOrig)
curSize = srcLenOrig;
memcpy(p->buf + p->bufTotal, src, curSize);
*srcLen += curSize;
src += curSize;
srcLenOrig -= curSize;
p->bufTotal += curSize;
}
if (p->bufTotal == 0)
break;
switch (p->methodId)
{
case XZ_ID_Delta:
if (p->encodeMode)
Delta_Encode(p->deltaState, p->delta, p->buf, p->bufTotal);
else
Delta_Decode(p->deltaState, p->delta, p->buf, p->bufTotal);
p->bufConv = p->bufTotal;
break;
case XZ_ID_X86:
p->bufConv = x86_Convert(p->buf, p->bufTotal, p->ip, &p->x86State, p->encodeMode);
break;
CASE_BRA_CONV(PPC)
CASE_BRA_CONV(IA64)
CASE_BRA_CONV(ARM)
CASE_BRA_CONV(ARMT)
CASE_BRA_CONV(SPARC)
default:
return SZ_ERROR_UNSUPPORTED;
}
p->ip += (UInt32)p->bufConv;
if (p->bufConv == 0)
{
if (!srcWasFinished)
break;
p->bufConv = p->bufTotal;
}
}
if (p->bufTotal == p->bufPos && srcLenOrig == 0 && srcWasFinished)
*wasFinished = 1;
return SZ_OK;
}
SRes BraState_SetFromMethod(IStateCoder *p, UInt64 id, int encodeMode, ISzAlloc *alloc)
{
CBraState *decoder;
if (id != XZ_ID_Delta &&
id != XZ_ID_X86 &&
id != XZ_ID_PPC &&
id != XZ_ID_IA64 &&
id != XZ_ID_ARM &&
id != XZ_ID_ARMT &&
id != XZ_ID_SPARC)
return SZ_ERROR_UNSUPPORTED;
p->p = 0;
decoder = (CBraState *)alloc->Alloc(alloc, sizeof(CBraState));
if (decoder == 0)
return SZ_ERROR_MEM;
decoder->methodId = (UInt32)id;
decoder->encodeMode = encodeMode;
p->p = decoder;
p->Free = BraState_Free;
p->SetProps = BraState_SetProps;
p->Init = BraState_Init;
p->Code = BraState_Code;
return SZ_OK;
}
/* ---------- SbState ---------- */
#ifdef USE_SUBBLOCK
static void SbState_Free(void *pp, ISzAlloc *alloc)
{
CSbDec *p = (CSbDec *)pp;
SbDec_Free(p);
alloc->Free(alloc, pp);
}
static SRes SbState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAlloc *alloc)
{
UNUSED_VAR(pp);
UNUSED_VAR(props);
UNUSED_VAR(alloc);
return (propSize == 0) ? SZ_OK : SZ_ERROR_UNSUPPORTED;
}
static void SbState_Init(void *pp)
{
SbDec_Init((CSbDec *)pp);
}
static SRes SbState_Code(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
int srcWasFinished, ECoderFinishMode finishMode, int *wasFinished)
{
CSbDec *p = (CSbDec *)pp;
SRes res;
UNUSED_VAR(srcWasFinished);
p->dest = dest;
p->destLen = *destLen;
p->src = src;
p->srcLen = *srcLen;
p->finish = finishMode; /* change it */
res = SbDec_Decode((CSbDec *)pp);
*destLen -= p->destLen;
*srcLen -= p->srcLen;
*wasFinished = (*destLen == 0 && *srcLen == 0); /* change it */
return res;
}
SRes SbState_SetFromMethod(IStateCoder *p, ISzAlloc *alloc)
{
CSbDec *decoder;
p->p = 0;
decoder = alloc->Alloc(alloc, sizeof(CSbDec));
if (decoder == 0)
return SZ_ERROR_MEM;
p->p = decoder;
p->Free = SbState_Free;
p->SetProps = SbState_SetProps;
p->Init = SbState_Init;
p->Code = SbState_Code;
SbDec_Construct(decoder);
SbDec_SetAlloc(decoder, alloc);
return SZ_OK;
}
#endif
/* ---------- Lzma2State ---------- */
static void Lzma2State_Free(void *pp, ISzAlloc *alloc)
{
Lzma2Dec_Free((CLzma2Dec *)pp, alloc);
alloc->Free(alloc, pp);
}
static SRes Lzma2State_SetProps(void *pp, const Byte *props, size_t propSize, ISzAlloc *alloc)
{
if (propSize != 1)
return SZ_ERROR_UNSUPPORTED;
return Lzma2Dec_Allocate((CLzma2Dec *)pp, props[0], alloc);
}
static void Lzma2State_Init(void *pp)
{
Lzma2Dec_Init((CLzma2Dec *)pp);
}
static SRes Lzma2State_Code(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
int srcWasFinished, ECoderFinishMode finishMode, int *wasFinished)
{
ELzmaStatus status;
/* ELzmaFinishMode fm = (finishMode == LZMA_FINISH_ANY) ? LZMA_FINISH_ANY : LZMA_FINISH_END; */
SRes res = Lzma2Dec_DecodeToBuf((CLzma2Dec *)pp, dest, destLen, src, srcLen, (ELzmaFinishMode)finishMode, &status);
UNUSED_VAR(srcWasFinished);
*wasFinished = (status == LZMA_STATUS_FINISHED_WITH_MARK);
return res;
}
static SRes Lzma2State_SetFromMethod(IStateCoder *p, ISzAlloc *alloc)
{
CLzma2Dec *decoder = (CLzma2Dec *)alloc->Alloc(alloc, sizeof(CLzma2Dec));
p->p = decoder;
if (decoder == 0)
return SZ_ERROR_MEM;
p->Free = Lzma2State_Free;
p->SetProps = Lzma2State_SetProps;
p->Init = Lzma2State_Init;
p->Code = Lzma2State_Code;
Lzma2Dec_Construct(decoder);
return SZ_OK;
}
void MixCoder_Construct(CMixCoder *p, ISzAlloc *alloc)
{
unsigned i;
p->alloc = alloc;
p->buf = NULL;
p->numCoders = 0;
for (i = 0; i < MIXCODER_NUM_FILTERS_MAX; i++)
p->coders[i].p = NULL;
}
void MixCoder_Free(CMixCoder *p)
{
unsigned i;
for (i = 0; i < p->numCoders; i++)
{
IStateCoder *sc = &p->coders[i];
if (p->alloc && sc->p)
sc->Free(sc->p, p->alloc);
}
p->numCoders = 0;
if (p->buf)
{
p->alloc->Free(p->alloc, p->buf);
p->buf = NULL; /* 9.31: the BUG was fixed */
}
}
void MixCoder_Init(CMixCoder *p)
{
unsigned i;
for (i = 0; i < MIXCODER_NUM_FILTERS_MAX - 1; i++)
{
p->size[i] = 0;
p->pos[i] = 0;
p->finished[i] = 0;
}
for (i = 0; i < p->numCoders; i++)
{
IStateCoder *coder = &p->coders[i];
coder->Init(coder->p);
}
}
SRes MixCoder_SetFromMethod(CMixCoder *p, unsigned coderIndex, UInt64 methodId)
{
IStateCoder *sc = &p->coders[coderIndex];
p->ids[coderIndex] = methodId;
switch (methodId)
{
case XZ_ID_LZMA2: return Lzma2State_SetFromMethod(sc, p->alloc);
#ifdef USE_SUBBLOCK
case XZ_ID_Subblock: return SbState_SetFromMethod(sc, p->alloc);
#endif
}
if (coderIndex == 0)
return SZ_ERROR_UNSUPPORTED;
return BraState_SetFromMethod(sc, methodId, 0, p->alloc);
}
SRes MixCoder_Code(CMixCoder *p, Byte *dest, SizeT *destLen,
const Byte *src, SizeT *srcLen, int srcWasFinished,
ECoderFinishMode finishMode, ECoderStatus *status)
{
SizeT destLenOrig = *destLen;
SizeT srcLenOrig = *srcLen;
Bool allFinished = True;
*destLen = 0;
*srcLen = 0;
*status = CODER_STATUS_NOT_FINISHED;
if (!p->buf)
{
p->buf = (Byte *)p->alloc->Alloc(p->alloc, CODER_BUF_SIZE * (MIXCODER_NUM_FILTERS_MAX - 1));
if (!p->buf)
return SZ_ERROR_MEM;
}
if (p->numCoders != 1)
finishMode = CODER_FINISH_ANY;
for (;;)
{
Bool processed = False;
unsigned i;
/*
if (p->numCoders == 1 && *destLen == destLenOrig && finishMode == LZMA_FINISH_ANY)
break;
*/
for (i = 0; i < p->numCoders; i++)
{
SRes res;
IStateCoder *coder = &p->coders[i];
Byte *destCur;
SizeT destLenCur, srcLenCur;
const Byte *srcCur;
int srcFinishedCur;
int encodingWasFinished;
if (i == 0)
{
srcCur = src;
srcLenCur = srcLenOrig - *srcLen;
srcFinishedCur = srcWasFinished;
}
else
{
srcCur = p->buf + (CODER_BUF_SIZE * (i - 1)) + p->pos[i - 1];
srcLenCur = p->size[i - 1] - p->pos[i - 1];
srcFinishedCur = p->finished[i - 1];
}
if (i == p->numCoders - 1)
{
destCur = dest;
destLenCur = destLenOrig - *destLen;
}
else
{
if (p->pos[i] != p->size[i])
continue;
destCur = p->buf + (CODER_BUF_SIZE * i);
destLenCur = CODER_BUF_SIZE;
}
res = coder->Code(coder->p, destCur, &destLenCur, srcCur, &srcLenCur, srcFinishedCur, finishMode, &encodingWasFinished);
if (!encodingWasFinished)
allFinished = False;
if (i == 0)
{
*srcLen += srcLenCur;
src += srcLenCur;
}
else
{
p->pos[i - 1] += srcLenCur;
}
if (i == p->numCoders - 1)
{
*destLen += destLenCur;
dest += destLenCur;
}
else
{
p->size[i] = destLenCur;
p->pos[i] = 0;
p->finished[i] = encodingWasFinished;
}
if (res != SZ_OK)
return res;
if (destLenCur != 0 || srcLenCur != 0)
processed = True;
}
if (!processed)
break;
}
if (allFinished)
*status = CODER_STATUS_FINISHED_WITH_MARK;
return SZ_OK;
}
SRes Xz_ParseHeader(CXzStreamFlags *p, const Byte *buf)
{
*p = (CXzStreamFlags)GetBe16(buf + XZ_SIG_SIZE);
if (CrcCalc(buf + XZ_SIG_SIZE, XZ_STREAM_FLAGS_SIZE) !=
GetUi32(buf + XZ_SIG_SIZE + XZ_STREAM_FLAGS_SIZE))
return SZ_ERROR_NO_ARCHIVE;
return XzFlags_IsSupported(*p) ? SZ_OK : SZ_ERROR_UNSUPPORTED;
}
static Bool Xz_CheckFooter(CXzStreamFlags flags, UInt64 indexSize, const Byte *buf)
{
return
indexSize == (((UInt64)GetUi32(buf + 4) + 1) << 2) &&
(GetUi32(buf) == CrcCalc(buf + 4, 6) &&
flags == GetBe16(buf + 8) &&
memcmp(buf + 10, XZ_FOOTER_SIG, XZ_FOOTER_SIG_SIZE) == 0);
}
#define READ_VARINT_AND_CHECK(buf, pos, size, res) \
{ unsigned s = Xz_ReadVarInt(buf + pos, size - pos, res); \
if (s == 0) return SZ_ERROR_ARCHIVE; pos += s; }
SRes XzBlock_Parse(CXzBlock *p, const Byte *header)
{
unsigned pos;
unsigned numFilters, i;
unsigned headerSize = (unsigned)header[0] << 2;
if (CrcCalc(header, headerSize) != GetUi32(header + headerSize))
return SZ_ERROR_ARCHIVE;
pos = 1;
if (pos == headerSize)
return SZ_ERROR_ARCHIVE;
p->flags = header[pos++];
if (XzBlock_HasPackSize(p))
{
READ_VARINT_AND_CHECK(header, pos, headerSize, &p->packSize);
if (p->packSize == 0 || p->packSize + headerSize >= (UInt64)1 << 63)
return SZ_ERROR_ARCHIVE;
}
if (XzBlock_HasUnpackSize(p))
READ_VARINT_AND_CHECK(header, pos, headerSize, &p->unpackSize);
numFilters = XzBlock_GetNumFilters(p);
for (i = 0; i < numFilters; i++)
{
CXzFilter *filter = p->filters + i;
UInt64 size;
READ_VARINT_AND_CHECK(header, pos, headerSize, &filter->id);
READ_VARINT_AND_CHECK(header, pos, headerSize, &size);
if (size > headerSize - pos || size > XZ_FILTER_PROPS_SIZE_MAX)
return SZ_ERROR_ARCHIVE;
filter->propsSize = (UInt32)size;
memcpy(filter->props, header + pos, (size_t)size);
pos += (unsigned)size;
#ifdef XZ_DUMP
printf("\nf[%u] = %2X: ", i, (unsigned)filter->id);
{
unsigned i;
for (i = 0; i < size; i++)
printf(" %2X", filter->props[i]);
}
#endif
}
while (pos < headerSize)
if (header[pos++] != 0)
return SZ_ERROR_ARCHIVE;
return SZ_OK;
}
SRes XzDec_Init(CMixCoder *p, const CXzBlock *block)
{
unsigned i;
Bool needReInit = True;
unsigned numFilters = XzBlock_GetNumFilters(block);
if (numFilters == p->numCoders)
{
for (i = 0; i < numFilters; i++)
if (p->ids[i] != block->filters[numFilters - 1 - i].id)
break;
needReInit = (i != numFilters);
}
if (needReInit)
{
MixCoder_Free(p);
p->numCoders = numFilters;
for (i = 0; i < numFilters; i++)
{
const CXzFilter *f = &block->filters[numFilters - 1 - i];
RINOK(MixCoder_SetFromMethod(p, i, f->id));
}
}
for (i = 0; i < numFilters; i++)
{
const CXzFilter *f = &block->filters[numFilters - 1 - i];
IStateCoder *sc = &p->coders[i];
RINOK(sc->SetProps(sc->p, f->props, f->propsSize, p->alloc));
}
MixCoder_Init(p);
return SZ_OK;
}
void XzUnpacker_Init(CXzUnpacker *p)
{
p->state = XZ_STATE_STREAM_HEADER;
p->pos = 0;
p->numStartedStreams = 0;
p->numFinishedStreams = 0;
p->numTotalBlocks = 0;
p->padSize = 0;
}
void XzUnpacker_Construct(CXzUnpacker *p, ISzAlloc *alloc)
{
MixCoder_Construct(&p->decoder, alloc);
XzUnpacker_Init(p);
}
void XzUnpacker_Free(CXzUnpacker *p)
{
MixCoder_Free(&p->decoder);
}
SRes XzUnpacker_Code(CXzUnpacker *p, Byte *dest, SizeT *destLen,
const Byte *src, SizeT *srcLen, ECoderFinishMode finishMode, ECoderStatus *status)
{
SizeT destLenOrig = *destLen;
SizeT srcLenOrig = *srcLen;
*destLen = 0;
*srcLen = 0;
*status = CODER_STATUS_NOT_SPECIFIED;
for (;;)
{
SizeT srcRem = srcLenOrig - *srcLen;
if (p->state == XZ_STATE_BLOCK)
{
SizeT destLen2 = destLenOrig - *destLen;
SizeT srcLen2 = srcLenOrig - *srcLen;
SRes res;
if (srcLen2 == 0 && destLen2 == 0)
{
*status = CODER_STATUS_NOT_FINISHED;
return SZ_OK;
}
res = MixCoder_Code(&p->decoder, dest, &destLen2, src, &srcLen2, False, finishMode, status);
XzCheck_Update(&p->check, dest, destLen2);
(*srcLen) += srcLen2;
src += srcLen2;
p->packSize += srcLen2;
(*destLen) += destLen2;
dest += destLen2;
p->unpackSize += destLen2;
RINOK(res);
if (*status == CODER_STATUS_FINISHED_WITH_MARK)
{
Byte temp[32];
unsigned num = Xz_WriteVarInt(temp, p->packSize + p->blockHeaderSize + XzFlags_GetCheckSize(p->streamFlags));
num += Xz_WriteVarInt(temp + num, p->unpackSize);
Sha256_Update(&p->sha, temp, num);
p->indexSize += num;
p->numBlocks++;
p->state = XZ_STATE_BLOCK_FOOTER;
p->pos = 0;
p->alignPos = 0;
}
else if (srcLen2 == 0 && destLen2 == 0)
return SZ_OK;
continue;
}
if (srcRem == 0)
{
*status = CODER_STATUS_NEEDS_MORE_INPUT;
return SZ_OK;
}
switch (p->state)
{
case XZ_STATE_STREAM_HEADER:
{
if (p->pos < XZ_STREAM_HEADER_SIZE)
{
if (p->pos < XZ_SIG_SIZE && *src != XZ_SIG[p->pos])
return SZ_ERROR_NO_ARCHIVE;
p->buf[p->pos++] = *src++;
(*srcLen)++;
}
else
{
RINOK(Xz_ParseHeader(&p->streamFlags, p->buf));
p->numStartedStreams++;
p->state = XZ_STATE_BLOCK_HEADER;
Sha256_Init(&p->sha);
p->indexSize = 0;
p->numBlocks = 0;
p->pos = 0;
}
break;
}
case XZ_STATE_BLOCK_HEADER:
{
if (p->pos == 0)
{
p->buf[p->pos++] = *src++;
(*srcLen)++;
if (p->buf[0] == 0)
{
p->indexPreSize = 1 + Xz_WriteVarInt(p->buf + 1, p->numBlocks);
p->indexPos = p->indexPreSize;
p->indexSize += p->indexPreSize;
Sha256_Final(&p->sha, p->shaDigest);
Sha256_Init(&p->sha);
p->crc = CrcUpdate(CRC_INIT_VAL, p->buf, p->indexPreSize);
p->state = XZ_STATE_STREAM_INDEX;
}
p->blockHeaderSize = ((UInt32)p->buf[0] << 2) + 4;
}
else if (p->pos != p->blockHeaderSize)
{
UInt32 cur = p->blockHeaderSize - p->pos;
if (cur > srcRem)
cur = (UInt32)srcRem;
memcpy(p->buf + p->pos, src, cur);
p->pos += cur;
(*srcLen) += cur;
src += cur;
}
else
{
RINOK(XzBlock_Parse(&p->block, p->buf));
p->numTotalBlocks++;
p->state = XZ_STATE_BLOCK;
p->packSize = 0;
p->unpackSize = 0;
XzCheck_Init(&p->check, XzFlags_GetCheckType(p->streamFlags));
RINOK(XzDec_Init(&p->decoder, &p->block));
}
break;
}
case XZ_STATE_BLOCK_FOOTER:
{
if (((p->packSize + p->alignPos) & 3) != 0)
{
(*srcLen)++;
p->alignPos++;
if (*src++ != 0)
return SZ_ERROR_CRC;
}
else
{
UInt32 checkSize = XzFlags_GetCheckSize(p->streamFlags);
UInt32 cur = checkSize - p->pos;
if (cur != 0)
{
if (cur > srcRem)
cur = (UInt32)srcRem;
memcpy(p->buf + p->pos, src, cur);
p->pos += cur;
(*srcLen) += cur;
src += cur;
}
else
{
Byte digest[XZ_CHECK_SIZE_MAX];
p->state = XZ_STATE_BLOCK_HEADER;
p->pos = 0;
if (XzCheck_Final(&p->check, digest) && memcmp(digest, p->buf, checkSize) != 0)
return SZ_ERROR_CRC;
}
}
break;
}
case XZ_STATE_STREAM_INDEX:
{
if (p->pos < p->indexPreSize)
{
(*srcLen)++;
if (*src++ != p->buf[p->pos++])
return SZ_ERROR_CRC;
}
else
{
if (p->indexPos < p->indexSize)
{
UInt64 cur = p->indexSize - p->indexPos;
if (srcRem > cur)
srcRem = (SizeT)cur;
p->crc = CrcUpdate(p->crc, src, srcRem);
Sha256_Update(&p->sha, src, srcRem);
(*srcLen) += srcRem;
src += srcRem;
p->indexPos += srcRem;
}
else if ((p->indexPos & 3) != 0)
{
Byte b = *src++;
p->crc = CRC_UPDATE_BYTE(p->crc, b);
(*srcLen)++;
p->indexPos++;
p->indexSize++;
if (b != 0)
return SZ_ERROR_CRC;
}
else
{
Byte digest[SHA256_DIGEST_SIZE];
p->state = XZ_STATE_STREAM_INDEX_CRC;
p->indexSize += 4;
p->pos = 0;
Sha256_Final(&p->sha, digest);
if (memcmp(digest, p->shaDigest, SHA256_DIGEST_SIZE) != 0)
return SZ_ERROR_CRC;
}
}
break;
}
case XZ_STATE_STREAM_INDEX_CRC:
{
if (p->pos < 4)
{
(*srcLen)++;
p->buf[p->pos++] = *src++;
}
else
{
p->state = XZ_STATE_STREAM_FOOTER;
p->pos = 0;
if (CRC_GET_DIGEST(p->crc) != GetUi32(p->buf))
return SZ_ERROR_CRC;
}
break;
}
case XZ_STATE_STREAM_FOOTER:
{
UInt32 cur = XZ_STREAM_FOOTER_SIZE - p->pos;
if (cur > srcRem)
cur = (UInt32)srcRem;
memcpy(p->buf + p->pos, src, cur);
p->pos += cur;
(*srcLen) += cur;
src += cur;
if (p->pos == XZ_STREAM_FOOTER_SIZE)
{
p->state = XZ_STATE_STREAM_PADDING;
p->numFinishedStreams++;
p->padSize = 0;
if (!Xz_CheckFooter(p->streamFlags, p->indexSize, p->buf))
return SZ_ERROR_CRC;
}
break;
}
case XZ_STATE_STREAM_PADDING:
{
if (*src != 0)
{
if (((UInt32)p->padSize & 3) != 0)
return SZ_ERROR_NO_ARCHIVE;
p->pos = 0;
p->state = XZ_STATE_STREAM_HEADER;
}
else
{
(*srcLen)++;
src++;
p->padSize++;
}
break;
}
case XZ_STATE_BLOCK: break; /* to disable GCC warning */
}
}
/*
if (p->state == XZ_STATE_FINISHED)
*status = CODER_STATUS_FINISHED_WITH_MARK;
return SZ_OK;
*/
}
Bool XzUnpacker_IsStreamWasFinished(CXzUnpacker *p)
{
return (p->state == XZ_STATE_STREAM_PADDING) && (((UInt32)p->padSize & 3) == 0);
}
UInt64 XzUnpacker_GetExtraSize(CXzUnpacker *p)
{
UInt64 num = 0;
if (p->state == XZ_STATE_STREAM_PADDING)
num += p->padSize;
else if (p->state == XZ_STATE_STREAM_HEADER)
num += p->padSize + p->pos;
return num;
}