chromium/third_party/lzma_sdk/C/XzDec.c

/* XzDec.c -- Xz Decode
2021-09-04 : Igor Pavlov : Public domain */

#include "Precomp.h"

// #include <stdio.h>

// #define XZ_DUMP

/* #define XZ_DUMP */

#ifdef XZ_DUMP
#include <stdio.h>
#endif

// #define SHOW_DEBUG_INFO

#ifdef SHOW_DEBUG_INFO
#include <stdio.h>
#endif

#ifdef SHOW_DEBUG_INFO
#define PRF …
#else
#define PRF(x) …
#endif

#define PRF_STR(s) …
#define PRF_STR_INT(s, d) …

#include <stdlib.h>
#include <string.h>

#include "7zCrc.h"
#include "Alloc.h"
#include "Bra.h"
#include "CpuArch.h"
#include "Delta.h"
#include "Lzma2Dec.h"

// #define USE_SUBBLOCK

#ifdef USE_SUBBLOCK
#include "Bcj3Dec.c"
#include "SbDec.h"
#endif

#include "Xz.h"

#define XZ_CHECK_SIZE_MAX …

#define CODER_BUF_SIZE …

unsigned Xz_ReadVarInt(const Byte *p, size_t maxSize, UInt64 *value)
{ … }

/* ---------- BraState ---------- */

#define BRA_BUF_SIZE …

CBraState;

static void BraState_Free(void *pp, ISzAllocPtr alloc)
{ … }

static SRes BraState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAllocPtr alloc)
{ … }

static void BraState_Init(void *pp)
{ … }


#define CASE_BRA_CONV(isa) …

static SizeT BraState_Filter(void *pp, Byte *data, SizeT size)
{ … }


static SRes BraState_Code2(void *pp,
    Byte *dest, SizeT *destLen,
    const Byte *src, SizeT *srcLen, int srcWasFinished,
    ECoderFinishMode finishMode,
    // int *wasFinished
    ECoderStatus *status)
{ … }


SRes BraState_SetFromMethod(IStateCoder *p, UInt64 id, int encodeMode, ISzAllocPtr alloc);
SRes BraState_SetFromMethod(IStateCoder *p, UInt64 id, int encodeMode, ISzAllocPtr alloc)
{ … }



/* ---------- SbState ---------- */

#ifdef USE_SUBBLOCK

static void SbState_Free(void *pp, ISzAllocPtr alloc)
{
  CSbDec *p = (CSbDec *)pp;
  SbDec_Free(p);
  ISzAlloc_Free(alloc, pp);
}

static SRes SbState_SetProps(void *pp, const Byte *props, size_t propSize, ISzAllocPtr 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_Code2(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
    int srcWasFinished, ECoderFinishMode finishMode,
    // int *wasFinished
    ECoderStatus *status)
{
  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 */
  *status = (*destLen == 0 && *srcLen == 0) ?
      CODER_STATUS_FINISHED_WITH_MARK :
      CODER_STATUS_NOT_FINISHED;
  return res;
}

static SRes SbState_SetFromMethod(IStateCoder *p, ISzAllocPtr alloc)
{
  CSbDec *decoder = (CSbDec *)p->p;
  if (!decoder)
  {
    decoder = (CSbDec *)ISzAlloc_Alloc(alloc, sizeof(CSbDec));
    if (!decoder)
      return SZ_ERROR_MEM;
    p->p = decoder;
    p->Free = SbState_Free;
    p->SetProps = SbState_SetProps;
    p->Init = SbState_Init;
    p->Code2 = SbState_Code2;
    p->Filter = NULL;
  }
  SbDec_Construct(decoder);
  SbDec_SetAlloc(decoder, alloc);
  return SZ_OK;
}

#endif



/* ---------- Lzma2 ---------- */

CLzma2Dec_Spec;


static void Lzma2State_Free(void *pp, ISzAllocPtr alloc)
{ … }

static SRes Lzma2State_SetProps(void *pp, const Byte *props, size_t propSize, ISzAllocPtr alloc)
{ … }

static void Lzma2State_Init(void *pp)
{ … }


/*
  if (outBufMode), then (dest) is not used. Use NULL.
         Data is unpacked to (spec->decoder.decoder.dic) output buffer.
*/

static SRes Lzma2State_Code2(void *pp, Byte *dest, SizeT *destLen, const Byte *src, SizeT *srcLen,
    int srcWasFinished, ECoderFinishMode finishMode,
    // int *wasFinished,
    ECoderStatus *status)
{ … }


static SRes Lzma2State_SetFromMethod(IStateCoder *p, Byte *outBuf, size_t outBufSize, ISzAllocPtr alloc)
{ … }


static SRes Lzma2State_ResetOutBuf(IStateCoder *p, Byte *outBuf, size_t outBufSize)
{ … }



static void MixCoder_Construct(CMixCoder *p, ISzAllocPtr alloc)
{ … }


static void MixCoder_Free(CMixCoder *p)
{ … }

static void MixCoder_Init(CMixCoder *p)
{ … }


static SRes MixCoder_SetFromMethod(CMixCoder *p, unsigned coderIndex, UInt64 methodId, Byte *outBuf, size_t outBufSize)
{ … }


static SRes MixCoder_ResetFromMethod(CMixCoder *p, unsigned coderIndex, UInt64 methodId, Byte *outBuf, size_t outBufSize)
{ … }



/*
 if (destFinish) - then unpack data block is finished at (*destLen) position,
                   and we can return data that were not processed by filter

output (status) can be :
  CODER_STATUS_NOT_FINISHED
  CODER_STATUS_FINISHED_WITH_MARK
  CODER_STATUS_NEEDS_MORE_INPUT - not implemented still
*/

static SRes MixCoder_Code(CMixCoder *p,
    Byte *dest, SizeT *destLen, int destFinish,
    const Byte *src, SizeT *srcLen, int srcWasFinished,
    ECoderFinishMode finishMode)
{ … }


SRes Xz_ParseHeader(CXzStreamFlags *p, const Byte *buf)
{ … }

static BoolInt Xz_CheckFooter(CXzStreamFlags flags, UInt64 indexSize, const Byte *buf)
{ … }

#define READ_VARINT_AND_CHECK(buf, pos, size, res) …


static BoolInt XzBlock_AreSupportedFilters(const CXzBlock *p)
{ … }


SRes XzBlock_Parse(CXzBlock *p, const Byte *header)
{ … }




static SRes XzDecMix_Init(CMixCoder *p, const CXzBlock *block, Byte *outBuf, size_t outBufSize)
{ … }



void XzUnpacker_Init(CXzUnpacker *p)
{ … }


void XzUnpacker_SetOutBuf(CXzUnpacker *p, Byte *outBuf, size_t outBufSize)
{ … }


void XzUnpacker_Construct(CXzUnpacker *p, ISzAllocPtr alloc)
{ … }


void XzUnpacker_Free(CXzUnpacker *p)
{ … }


void XzUnpacker_PrepareToRandomBlockDecoding(CXzUnpacker *p)
{ … }


static void XzUnpacker_UpdateIndex(CXzUnpacker *p, UInt64 packSize, UInt64 unpackSize)
{ … }



SRes XzUnpacker_Code(CXzUnpacker *p, Byte *dest, SizeT *destLen,
    const Byte *src, SizeT *srcLen, int srcFinished,
    ECoderFinishMode finishMode, ECoderStatus *status)
{ … }


SRes XzUnpacker_CodeFull(CXzUnpacker *p, Byte *dest, SizeT *destLen,
    const Byte *src, SizeT *srcLen,
    ECoderFinishMode finishMode, ECoderStatus *status)
{ … }


BoolInt XzUnpacker_IsBlockFinished(const CXzUnpacker *p)
{ … }

BoolInt XzUnpacker_IsStreamWasFinished(const CXzUnpacker *p)
{ … }

UInt64 XzUnpacker_GetExtraSize(const CXzUnpacker *p)
{ … }





















#ifndef _7ZIP_ST
#include "MtDec.h"
#endif


void XzDecMtProps_Init(CXzDecMtProps *p)
{ … }



#ifndef _7ZIP_ST

/* ---------- CXzDecMtThread ---------- */

typedef struct
{
  Byte *outBuf;
  size_t outBufSize;
  size_t outPreSize;
  size_t inPreSize;
  size_t inPreHeaderSize;
  size_t blockPackSize_for_Index;  // including block header and checksum.
  size_t blockPackTotal;  // including stream header, block header and checksum.
  size_t inCodeSize;
  size_t outCodeSize;
  ECoderStatus status;
  SRes codeRes;
  BoolInt skipMode;
  // BoolInt finishedWithMark;
  EMtDecParseState parseState;
  BoolInt parsing_Truncated;
  BoolInt atBlockHeader;
  CXzStreamFlags streamFlags;
  // UInt64 numFinishedStreams
  UInt64 numStreams;
  UInt64 numTotalBlocks;
  UInt64 numBlocks;

  BoolInt dec_created;
  CXzUnpacker dec;

  Byte mtPad[1 << 7];
} CXzDecMtThread;

#endif


/* ---------- CXzDecMt ---------- */

CXzDecMt;



CXzDecMtHandle XzDecMt_Create(ISzAllocPtr alloc, ISzAllocPtr allocMid)
{ … }


#ifndef _7ZIP_ST

static void XzDecMt_FreeOutBufs(CXzDecMt *p)
{
  unsigned i;
  for (i = 0; i < MTDEC__THREADS_MAX; i++)
  {
    CXzDecMtThread *coder = &p->coders[i];
    if (coder->outBuf)
    {
      ISzAlloc_Free(p->allocMid, coder->outBuf);
      coder->outBuf = NULL;
      coder->outBufSize = 0;
    }
  }
  p->unpackBlockMaxSize = 0;
}

#endif



static void XzDecMt_FreeSt(CXzDecMt *p)
{ … }


void XzDecMt_Destroy(CXzDecMtHandle pp)
{ … }



#ifndef _7ZIP_ST

static void XzDecMt_Callback_Parse(void *obj, unsigned coderIndex, CMtDecCallbackInfo *cc)
{
  CXzDecMt *me = (CXzDecMt *)obj;
  CXzDecMtThread *coder = &me->coders[coderIndex];
  size_t srcSize = cc->srcSize;

  cc->srcSize = 0;
  cc->outPos = 0;
  cc->state = MTDEC_PARSE_CONTINUE;

  cc->canCreateNewThread = True;

  if (cc->startCall)
  {
    coder->outPreSize = 0;
    coder->inPreSize = 0;
    coder->inPreHeaderSize = 0;
    coder->parseState = MTDEC_PARSE_CONTINUE;
    coder->parsing_Truncated = False;
    coder->skipMode = False;
    coder->codeRes = SZ_OK;
    coder->status = CODER_STATUS_NOT_SPECIFIED;
    coder->inCodeSize = 0;
    coder->outCodeSize = 0;

    coder->numStreams = me->numStreams;
    coder->numTotalBlocks = me->numTotalBlocks;
    coder->numBlocks = me->numBlocks;

    if (!coder->dec_created)
    {
      XzUnpacker_Construct(&coder->dec, &me->alignOffsetAlloc.vt);
      coder->dec_created = True;
    }
    
    XzUnpacker_Init(&coder->dec);

    if (me->isBlockHeaderState_Parse)
    {
      coder->dec.streamFlags = me->streamFlags;
      coder->atBlockHeader = True;
      XzUnpacker_PrepareToRandomBlockDecoding(&coder->dec);
    }
    else
    {
      coder->atBlockHeader = False;
      me->isBlockHeaderState_Parse = True;
    }

    coder->dec.numStartedStreams = me->numStreams;
    coder->dec.numTotalBlocks = me->numTotalBlocks;
    coder->dec.numBlocks = me->numBlocks;
  }

  while (!coder->skipMode)
  {
    ECoderStatus status;
    SRes res;
    size_t srcSize2 = srcSize;
    size_t destSize = (size_t)0 - 1;

    coder->dec.parseMode = True;
    coder->dec.headerParsedOk = False;
    
    PRF_STR_INT("Parse", srcSize2);
    
    res = XzUnpacker_Code(&coder->dec,
        NULL, &destSize,
        cc->src, &srcSize2, cc->srcFinished,
        CODER_FINISH_END, &status);
    
    // PRF(printf(" res = %d, srcSize2 = %d", res, (unsigned)srcSize2));
    
    coder->codeRes = res;
    coder->status = status;
    cc->srcSize += srcSize2;
    srcSize -= srcSize2;
    coder->inPreHeaderSize += srcSize2;
    coder->inPreSize = coder->inPreHeaderSize;
    
    if (res != SZ_OK)
    {
      cc->state =
      coder->parseState = MTDEC_PARSE_END;
      /*
      if (res == SZ_ERROR_MEM)
        return res;
      return SZ_OK;
      */
      return; // res;
    }
    
    if (coder->dec.headerParsedOk)
    {
      const CXzBlock *block = &coder->dec.block;
      if (XzBlock_HasUnpackSize(block)
          // && block->unpackSize <= me->props.outBlockMax
          && XzBlock_HasPackSize(block))
      {
        {
          if (block->unpackSize * 2 * me->mtc.numStartedThreads > me->props.memUseMax)
          {
            cc->state = MTDEC_PARSE_OVERFLOW;
            return; // SZ_OK;
          }
        }
        {
        UInt64 packSize = block->packSize;
        UInt64 packSizeAligned = packSize + ((0 - (unsigned)packSize) & 3);
        UInt32 checkSize = XzFlags_GetCheckSize(coder->dec.streamFlags);
        UInt64 blockPackSum = coder->inPreSize + packSizeAligned + checkSize;
        // if (blockPackSum <= me->props.inBlockMax)
        // unpackBlockMaxSize
        {
          coder->blockPackSize_for_Index = (size_t)(coder->dec.blockHeaderSize + packSize + checkSize);
          coder->blockPackTotal = (size_t)blockPackSum;
          coder->outPreSize = (size_t)block->unpackSize;
          coder->streamFlags = coder->dec.streamFlags;
          me->streamFlags = coder->dec.streamFlags;
          coder->skipMode = True;
          break;
        }
        }
      }
    }
    else
    // if (coder->inPreSize <= me->props.inBlockMax)
    {
      if (!cc->srcFinished)
        return; // SZ_OK;
      cc->state =
      coder->parseState = MTDEC_PARSE_END;
      return; // SZ_OK;
    }
    cc->state = MTDEC_PARSE_OVERFLOW;
    return; // SZ_OK;
  }

  // ---------- skipMode ----------
  {
    UInt64 rem = coder->blockPackTotal - coder->inPreSize;
    size_t cur = srcSize;
    if (cur > rem)
      cur = (size_t)rem;
    cc->srcSize += cur;
    coder->inPreSize += cur;
    srcSize -= cur;

    if (coder->inPreSize == coder->blockPackTotal)
    {
      if (srcSize == 0)
      {
        if (!cc->srcFinished)
          return; // SZ_OK;
        cc->state = MTDEC_PARSE_END;
      }
      else if ((cc->src)[cc->srcSize] == 0) // we check control byte of next block
        cc->state = MTDEC_PARSE_END;
      else
      {
        cc->state = MTDEC_PARSE_NEW;

        {
          size_t blockMax = me->unpackBlockMaxSize;
          if (blockMax < coder->outPreSize)
            blockMax = coder->outPreSize;
          {
            UInt64 required = (UInt64)blockMax * (me->mtc.numStartedThreads + 1) * 2;
            if (me->props.memUseMax < required)
              cc->canCreateNewThread = False;
          }
        }

        if (me->outSize_Defined)
        {
          // next block can be zero size
          const UInt64 rem2 = me->outSize - me->outProcessed_Parse;
          if (rem2 < coder->outPreSize)
          {
            coder->parsing_Truncated = True;
            cc->state = MTDEC_PARSE_END;
          }
          me->outProcessed_Parse += coder->outPreSize;
        }
      }
    }
    else if (cc->srcFinished)
      cc->state = MTDEC_PARSE_END;
    else
      return; // SZ_OK;

    coder->parseState = cc->state;
    cc->outPos = coder->outPreSize;
    
    me->numStreams = coder->dec.numStartedStreams;
    me->numTotalBlocks = coder->dec.numTotalBlocks;
    me->numBlocks = coder->dec.numBlocks + 1;
    return; // SZ_OK;
  }
}


static SRes XzDecMt_Callback_PreCode(void *pp, unsigned coderIndex)
{
  CXzDecMt *me = (CXzDecMt *)pp;
  CXzDecMtThread *coder = &me->coders[coderIndex];
  Byte *dest;

  if (!coder->dec.headerParsedOk)
    return SZ_OK;

  dest = coder->outBuf;

  if (!dest || coder->outBufSize < coder->outPreSize)
  {
    if (dest)
    {
      ISzAlloc_Free(me->allocMid, dest);
      coder->outBuf = NULL;
      coder->outBufSize = 0;
    }
    {
      size_t outPreSize = coder->outPreSize;
      if (outPreSize == 0)
        outPreSize = 1;
      dest = (Byte *)ISzAlloc_Alloc(me->allocMid, outPreSize);
    }
    if (!dest)
      return SZ_ERROR_MEM;
    coder->outBuf = dest;
    coder->outBufSize = coder->outPreSize;

    if (coder->outBufSize > me->unpackBlockMaxSize)
      me->unpackBlockMaxSize = coder->outBufSize;
  }

  // return SZ_ERROR_MEM;

  XzUnpacker_SetOutBuf(&coder->dec, coder->outBuf, coder->outBufSize);

  {
    SRes res = XzDecMix_Init(&coder->dec.decoder, &coder->dec.block, coder->outBuf, coder->outBufSize);
    // res = SZ_ERROR_UNSUPPORTED; // to test
    coder->codeRes = res;
    if (res != SZ_OK)
    {
      // if (res == SZ_ERROR_MEM) return res;
      if (me->props.ignoreErrors && res != SZ_ERROR_MEM)
        return SZ_OK;
      return res;
    }
  }

  return SZ_OK;
}


static SRes XzDecMt_Callback_Code(void *pp, unsigned coderIndex,
    const Byte *src, size_t srcSize, int srcFinished,
    // int finished, int blockFinished,
    UInt64 *inCodePos, UInt64 *outCodePos, int *stop)
{
  CXzDecMt *me = (CXzDecMt *)pp;
  CXzDecMtThread *coder = &me->coders[coderIndex];

  *inCodePos = coder->inCodeSize;
  *outCodePos = coder->outCodeSize;
  *stop = True;

  if (srcSize > coder->inPreSize - coder->inCodeSize)
    return SZ_ERROR_FAIL;
  
  if (coder->inCodeSize < coder->inPreHeaderSize)
  {
    size_t step = coder->inPreHeaderSize - coder->inCodeSize;
    if (step > srcSize)
      step = srcSize;
    src += step;
    srcSize -= step;
    coder->inCodeSize += step;
    *inCodePos = coder->inCodeSize;
    if (coder->inCodeSize < coder->inPreHeaderSize)
    {
      *stop = False;
      return SZ_OK;
    }
  }

  if (!coder->dec.headerParsedOk)
    return SZ_OK;
  if (!coder->outBuf)
    return SZ_OK;

  if (coder->codeRes == SZ_OK)
  {
    ECoderStatus status;
    SRes res;
    size_t srcProcessed = srcSize;
    size_t outSizeCur = coder->outPreSize - coder->dec.outDataWritten;

    // PRF(printf("\nCallback_Code: Code %d %d\n", (unsigned)srcSize, (unsigned)outSizeCur));

    res = XzUnpacker_Code(&coder->dec,
        NULL, &outSizeCur,
        src, &srcProcessed, srcFinished,
        // coder->finishedWithMark ? CODER_FINISH_END : CODER_FINISH_ANY,
        CODER_FINISH_END,
        &status);

    // PRF(printf(" res = %d, srcSize2 = %d, outSizeCur = %d", res, (unsigned)srcProcessed, (unsigned)outSizeCur));

    coder->codeRes = res;
    coder->status = status;
    coder->inCodeSize += srcProcessed;
    coder->outCodeSize = coder->dec.outDataWritten;
    *inCodePos = coder->inCodeSize;
    *outCodePos = coder->outCodeSize;

    if (res == SZ_OK)
    {
      if (srcProcessed == srcSize)
        *stop = False;
      return SZ_OK;
    }
  }

  if (me->props.ignoreErrors && coder->codeRes != SZ_ERROR_MEM)
  {
    *inCodePos = coder->inPreSize;
    *outCodePos = coder->outPreSize;
    return SZ_OK;
  }
  return coder->codeRes;
}


#define XZDECMT_STREAM_WRITE_STEP …

static SRes XzDecMt_Callback_Write(void *pp, unsigned coderIndex,
    BoolInt needWriteToStream,
    const Byte *src, size_t srcSize, BoolInt isCross,
    // int srcFinished,
    BoolInt *needContinue,
    BoolInt *canRecode)
{
  CXzDecMt *me = (CXzDecMt *)pp;
  const CXzDecMtThread *coder = &me->coders[coderIndex];

  // PRF(printf("\nWrite processed = %d srcSize = %d\n", (unsigned)me->mtc.inProcessed, (unsigned)srcSize));
  
  *needContinue = False;
  *canRecode = True;
  
  if (!needWriteToStream)
    return SZ_OK;

  if (!coder->dec.headerParsedOk || !coder->outBuf)
  {
    if (me->finishedDecoderIndex < 0)
      me->finishedDecoderIndex = (int)coderIndex;
    return SZ_OK;
  }

  if (me->finishedDecoderIndex >= 0)
    return SZ_OK;

  me->mtc.inProcessed += coder->inCodeSize;

  *canRecode = False;

  {
    SRes res;
    size_t size = coder->outCodeSize;
    Byte *data = coder->outBuf;
    
    // we use in me->dec: sha, numBlocks, indexSize

    if (!me->isBlockHeaderState_Write)
    {
      XzUnpacker_PrepareToRandomBlockDecoding(&me->dec);
      me->dec.decodeOnlyOneBlock = False;
      me->dec.numStartedStreams = coder->dec.numStartedStreams;
      me->dec.streamFlags = coder->streamFlags;

      me->isBlockHeaderState_Write = True;
    }
    
    me->dec.numTotalBlocks = coder->dec.numTotalBlocks;
    XzUnpacker_UpdateIndex(&me->dec, coder->blockPackSize_for_Index, coder->outPreSize);
    
    if (coder->outPreSize != size)
    {
      if (me->props.ignoreErrors)
      {
        memset(data + size, 0, coder->outPreSize - size);
        size = coder->outPreSize;
      }
      // me->numBadBlocks++;
      if (me->mainErrorCode == SZ_OK)
      {
        if ((int)coder->status == LZMA_STATUS_NEEDS_MORE_INPUT)
          me->mainErrorCode = SZ_ERROR_INPUT_EOF;
        else
          me->mainErrorCode = SZ_ERROR_DATA;
      }
    }
    
    if (me->writeRes != SZ_OK)
      return me->writeRes;

    res = SZ_OK;
    {
      if (me->outSize_Defined)
      {
        const UInt64 rem = me->outSize - me->outProcessed;
        if (size > rem)
          size = (SizeT)rem;
      }

      for (;;)
      {
        size_t cur = size;
        size_t written;
        if (cur > XZDECMT_STREAM_WRITE_STEP)
          cur = XZDECMT_STREAM_WRITE_STEP;

        written = ISeqOutStream_Write(me->outStream, data, cur);

        // PRF(printf("\nWritten ask = %d written = %d\n", (unsigned)cur, (unsigned)written));
        
        me->outProcessed += written;
        if (written != cur)
        {
          me->writeRes = SZ_ERROR_WRITE;
          res = me->writeRes;
          break;
        }
        data += cur;
        size -= cur;
        // PRF_STR_INT("Written size =", size);
        if (size == 0)
          break;
        res = MtProgress_ProgressAdd(&me->mtc.mtProgress, 0, 0);
        if (res != SZ_OK)
          break;
      }
    }

    if (coder->codeRes != SZ_OK)
      if (!me->props.ignoreErrors)
      {
        me->finishedDecoderIndex = (int)coderIndex;
        return res;
      }

    RINOK(res);

    if (coder->inPreSize != coder->inCodeSize
        || coder->blockPackTotal != coder->inCodeSize)
    {
      me->finishedDecoderIndex = (int)coderIndex;
      return SZ_OK;
    }

    if (coder->parseState != MTDEC_PARSE_END)
    {
      *needContinue = True;
      return SZ_OK;
    }
  }

  // (coder->state == MTDEC_PARSE_END) means that there are no other working threads
  // so we can use mtc variables without lock

  PRF_STR_INT("Write MTDEC_PARSE_END", me->mtc.inProcessed);

  me->mtc.mtProgress.totalInSize = me->mtc.inProcessed;
  {
    CXzUnpacker *dec = &me->dec;
    
    PRF_STR_INT("PostSingle", srcSize);
    
    {
      size_t srcProcessed = srcSize;
      ECoderStatus status;
      size_t outSizeCur = 0;
      SRes res;
      
      // dec->decodeOnlyOneBlock = False;
      dec->decodeToStreamSignature = True;

      me->mainDecoderWasCalled = True;

      if (coder->parsing_Truncated)
      {
        me->parsing_Truncated = True;
        return SZ_OK;
      }
      
      /*
      We have processed all xz-blocks of stream,
      And xz unpacker is at XZ_STATE_BLOCK_HEADER state, where
      (src) is a pointer to xz-Index structure.
      We finish reading of current xz-Stream, including Zero padding after xz-Stream.
      We exit, if we reach extra byte (first byte of new-Stream or another data).
      But we don't update input stream pointer for that new extra byte.
      If extra byte is not correct first byte of xz-signature,
      we have SZ_ERROR_NO_ARCHIVE error here.
      */

      res = XzUnpacker_Code(dec,
          NULL, &outSizeCur,
          src, &srcProcessed,
          me->mtc.readWasFinished, // srcFinished
          CODER_FINISH_END, // CODER_FINISH_ANY,
          &status);

      // res = SZ_ERROR_ARCHIVE; // for failure test
      
      me->status = status;
      me->codeRes = res;

      if (isCross)
        me->mtc.crossStart += srcProcessed;

      me->mtc.inProcessed += srcProcessed;
      me->mtc.mtProgress.totalInSize = me->mtc.inProcessed;

      srcSize -= srcProcessed;
      src += srcProcessed;

      if (res != SZ_OK)
      {
        return SZ_OK;
        // return res;
      }
      
      if (dec->state == XZ_STATE_STREAM_HEADER)
      {
        *needContinue = True;
        me->isBlockHeaderState_Parse = False;
        me->isBlockHeaderState_Write = False;

        if (!isCross)
        {
          Byte *crossBuf = MtDec_GetCrossBuff(&me->mtc);
          if (!crossBuf)
            return SZ_ERROR_MEM;
          if (srcSize != 0)
            memcpy(crossBuf, src, srcSize);
          me->mtc.crossStart = 0;
          me->mtc.crossEnd = srcSize;
        }

        PRF_STR_INT("XZ_STATE_STREAM_HEADER crossEnd = ", (unsigned)me->mtc.crossEnd);

        return SZ_OK;
      }
      
      if (status != CODER_STATUS_NEEDS_MORE_INPUT || srcSize != 0)
      {
        return SZ_ERROR_FAIL;
      }
      
      if (me->mtc.readWasFinished)
      {
        return SZ_OK;
      }
    }
    
    {
      size_t inPos;
      size_t inLim;
      // const Byte *inData;
      UInt64 inProgressPrev = me->mtc.inProcessed;
      
      // XzDecMt_Prepare_InBuf_ST(p);
      Byte *crossBuf = MtDec_GetCrossBuff(&me->mtc);
      if (!crossBuf)
        return SZ_ERROR_MEM;
      
      inPos = 0;
      inLim = 0;
      
      // inData = crossBuf;
      
      for (;;)
      {
        SizeT inProcessed;
        SizeT outProcessed;
        ECoderStatus status;
        SRes res;
        
        if (inPos == inLim)
        {
          if (!me->mtc.readWasFinished)
          {
            inPos = 0;
            inLim = me->mtc.inBufSize;
            me->mtc.readRes = ISeqInStream_Read(me->inStream, (void *)crossBuf, &inLim);
            me->mtc.readProcessed += inLim;
            if (inLim == 0 || me->mtc.readRes != SZ_OK)
              me->mtc.readWasFinished = True;
          }
        }
        
        inProcessed = inLim - inPos;
        outProcessed = 0;

        res = XzUnpacker_Code(dec,
            NULL, &outProcessed,
            crossBuf + inPos, &inProcessed,
            (inProcessed == 0), // srcFinished
            CODER_FINISH_END, &status);
        
        me->codeRes = res;
        me->status = status;
        inPos += inProcessed;
        me->mtc.inProcessed += inProcessed;
        me->mtc.mtProgress.totalInSize = me->mtc.inProcessed;

        if (res != SZ_OK)
        {
          return SZ_OK;
          // return res;
        }

        if (dec->state == XZ_STATE_STREAM_HEADER)
        {
          *needContinue = True;
          me->mtc.crossStart = inPos;
          me->mtc.crossEnd = inLim;
          me->isBlockHeaderState_Parse = False;
          me->isBlockHeaderState_Write = False;
          return SZ_OK;
        }
        
        if (status != CODER_STATUS_NEEDS_MORE_INPUT)
          return SZ_ERROR_FAIL;
        
        if (me->mtc.progress)
        {
          UInt64 inDelta = me->mtc.inProcessed - inProgressPrev;
          if (inDelta >= (1 << 22))
          {
            RINOK(MtProgress_Progress_ST(&me->mtc.mtProgress));
            inProgressPrev = me->mtc.inProcessed;
          }
        }
        if (me->mtc.readWasFinished)
          return SZ_OK;
      }
    }
  }
}


#endif



void XzStatInfo_Clear(CXzStatInfo *p)
{ … }



/*
  XzDecMt_Decode_ST() can return SZ_OK or the following errors
     - SZ_ERROR_MEM for memory allocation error
     - error from XzUnpacker_Code() function
     - SZ_ERROR_WRITE for ISeqOutStream::Write(). stat->CombinedRes_Type = SZ_ERROR_WRITE in that case
     - ICompressProgress::Progress() error,  stat->CombinedRes_Type = SZ_ERROR_PROGRESS.
  But XzDecMt_Decode_ST() doesn't return ISeqInStream::Read() errors.
  ISeqInStream::Read() result is set to p->readRes.
  also it can set stat->CombinedRes_Type to SZ_ERROR_WRITE or SZ_ERROR_PROGRESS.
*/

static SRes XzDecMt_Decode_ST(CXzDecMt *p
    #ifndef _7ZIP_ST
    , BoolInt tMode
    #endif
    , CXzStatInfo *stat)
{ … }



/*
XzStatInfo_SetStat() transforms
    CXzUnpacker return code and status to combined CXzStatInfo results.
    it can convert SZ_OK to SZ_ERROR_INPUT_EOF
    it can convert SZ_ERROR_NO_ARCHIVE to SZ_OK and (DataAfterEnd = 1)
*/

static void XzStatInfo_SetStat(const CXzUnpacker *dec,
    int finishMode,
    // UInt64 readProcessed,
    UInt64 inProcessed,
    SRes res,                     // it's result from CXzUnpacker unpacker
    ECoderStatus status,
    BoolInt decodingTruncated,
    CXzStatInfo *stat)
{ … }



SRes XzDecMt_Decode(CXzDecMtHandle pp,
    const CXzDecMtProps *props,
    const UInt64 *outDataSize, int finishMode,
    ISeqOutStream *outStream,
    // Byte *outBuf, size_t *outBufSize,
    ISeqInStream *inStream,
    // const Byte *inData, size_t inDataSize,
    CXzStatInfo *stat,
    int *isMT,
    ICompressProgress *progress)
{ … }