Upgrading lzma_sdk to version 9.20.

third_party/lzma_sdk/C/XzDec.c

+/* XzDec.c -- Xz Decode
+2010-04-16 : Igor Pavlov : Public domain */
+
+/* #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 "SbDec.h"
+#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)
+{
+  int i, limit;
+  *value = 0;
+  limit = (maxSize > 9) ? 9 : (int)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;
+
+void BraState_Free(void *pp, ISzAlloc *alloc)
+{
+  alloc->Free(alloc, pp);
+}
+
+SRes BraState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAlloc *alloc)
+{
+  CBraState *p = ((CBraState *)pp);
+  alloc = alloc;
+  p->encodeMode = 0;
+  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;
+}
+
+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;
+  *destLen = 0;
+  *srcLen = 0;
+  finishMode = finishMode;
+  *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, 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 = alloc->Alloc(alloc, sizeof(CBraState));
+  if (decoder == 0)
+    return SZ_ERROR_MEM;
+  decoder->methodId = (UInt32)id;
+  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)
+{
+  CSubblockDec *p = (CSubblockDec *)pp;
+  SubblockDec_Free(p, alloc);
+  alloc->Free(alloc, pp);
+}
+
+static SRes SbState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAlloc *alloc)
+{
+  pp = pp;
+  props = props;
+  alloc = alloc;
+  return (propSize == 0) ? SZ_OK : SZ_ERROR_UNSUPPORTED;
+}
+
+static void SbState_Init(void *pp)
+{
+  SubblockDec_Init((CSubblockDec *)pp);
+}
+
+static SRes SbState_Code(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
+    int srcWasFinished, ECoderFinishMode finishMode, int *wasFinished)
+{
+  ECoderStatus status;
+  SRes res = SubblockDec_Decode((CSubblockDec *)pp, dest, destLen, src, srcLen, finishMode, &status);
+  srcWasFinished = srcWasFinished;
+  *wasFinished = (status == LZMA_STATUS_FINISHED_WITH_MARK);
+  return res;
+}
+
+SRes SbState_SetFromMethod(IStateCoder *p, ISzAlloc *alloc)
+{
+  CSubblockDec *decoder;
+  p->p = 0;
+  decoder = alloc->Alloc(alloc, sizeof(CSubblockDec));
+  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;
+  SubblockDec_Construct(decoder);
+  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, finishMode, &status);
+  srcWasFinished = srcWasFinished;
+  *wasFinished = (status == LZMA_STATUS_FINISHED_WITH_MARK);
+  return res;
+}
+
+static SRes Lzma2State_SetFromMethod(IStateCoder *p, ISzAlloc *alloc)
+{
+  CLzma2Dec *decoder = 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)
+{
+  int i;
+  p->alloc = alloc;
+  p->buf = 0;
+  p->numCoders = 0;
+  for (i = 0; i < MIXCODER_NUM_FILTERS_MAX; i++)
+    p->coders[i].p = NULL;
+}
+
+void MixCoder_Free(CMixCoder *p)
+{
+  int 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);
+}
+
+void MixCoder_Init(CMixCoder *p)
+{
+  int i;
+  for (i = 0; i < p->numCoders - 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, int 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, 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 == 0)
+  {
+    p->buf = p->alloc->Alloc(p->alloc, CODER_BUF_SIZE * (MIXCODER_NUM_FILTERS_MAX - 1));
+    if (p->buf == 0)
+      return SZ_ERROR_MEM;
+  }
+
+  if (p->numCoders != 1)
+    finishMode = CODER_FINISH_ANY;
+
+  for (;;)
+  {
+    Bool processed = False;
+    int 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;
+  int numFilters, i;
+  UInt32 headerSize = (UInt32)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[%d] = %2X: ", i, filter->id);
+    {
+      int 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)
+{
+  int i;
+  Bool needReInit = True;
+  int 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;
+}
+
+SRes XzUnpacker_Create(CXzUnpacker *p, ISzAlloc *alloc)
+{
+  MixCoder_Construct(&p->decoder, alloc);
+  p->state = XZ_STATE_STREAM_HEADER;
+  p->pos = 0;
+  p->numStreams = 0;
+  return SZ_OK;
+}
+
+void XzUnpacker_Free(CXzUnpacker *p)
+{
+  MixCoder_Free(&p->decoder);
+}
+
+SRes XzUnpacker_Code(CXzUnpacker *p, Byte *dest, SizeT *destLen,
+    const Byte *src, SizeT *srcLen, int 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->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->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->numStreams++;
+          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);
+}