Update lzma_sdk sources to 15.14.

third_party/lzma_sdk/7zArcIn.c

+/* 7zArcIn.c -- 7z Input functions
+2015-11-18 : Igor Pavlov : Public domain */
+
+#include "Precomp.h"
+
+#include <string.h>
+
+#include "7z.h"
+#include "7zBuf.h"
+#include "7zCrc.h"
+#include "CpuArch.h"
+
+#define MY_ALLOC(T, p, size, alloc) { \
+  if ((p = (T *)IAlloc_Alloc(alloc, (size) * sizeof(T))) == NULL) return SZ_ERROR_MEM; }
+
+#define MY_ALLOC_ZE(T, p, size, alloc) { if ((size) == 0) p = NULL; else MY_ALLOC(T, p, size, alloc) }
+
+#define MY_ALLOC_AND_CPY(to, size, from, alloc) \
+  { MY_ALLOC(Byte, to, size, alloc); memcpy(to, from, size); }
+
+#define MY_ALLOC_ZE_AND_CPY(to, size, from, alloc) \
+  { if ((size) == 0) p = NULL; else { MY_ALLOC_AND_CPY(to, size, from, alloc) } }
+
+#define k7zMajorVersion 0
+
+enum EIdEnum
+{
+  k7zIdEnd,
+  k7zIdHeader,
+  k7zIdArchiveProperties,
+  k7zIdAdditionalStreamsInfo,
+  k7zIdMainStreamsInfo,
+  k7zIdFilesInfo,
+  k7zIdPackInfo,
+  k7zIdUnpackInfo,
+  k7zIdSubStreamsInfo,
+  k7zIdSize,
+  k7zIdCRC,
+  k7zIdFolder,
+  k7zIdCodersUnpackSize,
+  k7zIdNumUnpackStream,
+  k7zIdEmptyStream,
+  k7zIdEmptyFile,
+  k7zIdAnti,
+  k7zIdName,
+  k7zIdCTime,
+  k7zIdATime,
+  k7zIdMTime,
+  k7zIdWinAttrib,
+  k7zIdComment,
+  k7zIdEncodedHeader,
+  k7zIdStartPos,
+  k7zIdDummy
+  // k7zNtSecure,
+  // k7zParent,
+  // k7zIsReal
+};
+
+const Byte k7zSignature[k7zSignatureSize] = {'7', 'z', 0xBC, 0xAF, 0x27, 0x1C};
+
+#define SzBitUi32s_Init(p) { (p)->Defs = NULL; (p)->Vals = NULL; }
+
+static SRes SzBitUi32s_Alloc(CSzBitUi32s *p, size_t num, ISzAlloc *alloc)
+{
+  if (num == 0)
+  {
+    p->Defs = NULL;
+    p->Vals = NULL;
+  }
+  else
+  {
+    MY_ALLOC(Byte, p->Defs, (num + 7) >> 3, alloc);
+    MY_ALLOC(UInt32, p->Vals, num, alloc);
+  }
+  return SZ_OK;
+}
+
+void SzBitUi32s_Free(CSzBitUi32s *p, ISzAlloc *alloc)
+{
+  IAlloc_Free(alloc, p->Defs); p->Defs = NULL;
+  IAlloc_Free(alloc, p->Vals); p->Vals = NULL;
+}
+
+#define SzBitUi64s_Init(p) { (p)->Defs = NULL; (p)->Vals = NULL; }
+
+void SzBitUi64s_Free(CSzBitUi64s *p, ISzAlloc *alloc)
+{
+  IAlloc_Free(alloc, p->Defs); p->Defs = NULL;
+  IAlloc_Free(alloc, p->Vals); p->Vals = NULL;
+}
+
+
+static void SzAr_Init(CSzAr *p)
+{
+  p->NumPackStreams = 0;
+  p->NumFolders = 0;
+  
+  p->PackPositions = NULL;
+  SzBitUi32s_Init(&p->FolderCRCs);
+
+  p->FoCodersOffsets = NULL;
+  p->FoStartPackStreamIndex = NULL;
+  p->FoToCoderUnpackSizes = NULL;
+  p->FoToMainUnpackSizeIndex = NULL;
+  p->CoderUnpackSizes = NULL;
+
+  p->CodersData = NULL;
+}
+
+static void SzAr_Free(CSzAr *p, ISzAlloc *alloc)
+{
+  IAlloc_Free(alloc, p->PackPositions);
+  SzBitUi32s_Free(&p->FolderCRCs, alloc);
+ 
+  IAlloc_Free(alloc, p->FoCodersOffsets);
+  IAlloc_Free(alloc, p->FoStartPackStreamIndex);
+  IAlloc_Free(alloc, p->FoToCoderUnpackSizes);
+  IAlloc_Free(alloc, p->FoToMainUnpackSizeIndex);
+  IAlloc_Free(alloc, p->CoderUnpackSizes);
+  
+  IAlloc_Free(alloc, p->CodersData);
+
+  SzAr_Init(p);
+}
+
+
+void SzArEx_Init(CSzArEx *p)
+{
+  SzAr_Init(&p->db);
+  
+  p->NumFiles = 0;
+  p->dataPos = 0;
+  
+  p->UnpackPositions = NULL;
+  p->IsDirs = NULL;
+  
+  p->FolderToFile = NULL;
+  p->FileToFolder = NULL;
+  
+  p->FileNameOffsets = NULL;
+  p->FileNames = NULL;
+  
+  SzBitUi32s_Init(&p->CRCs);
+  SzBitUi32s_Init(&p->Attribs);
+  // SzBitUi32s_Init(&p->Parents);
+  SzBitUi64s_Init(&p->MTime);
+  SzBitUi64s_Init(&p->CTime);
+}
+
+void SzArEx_Free(CSzArEx *p, ISzAlloc *alloc)
+{
+  IAlloc_Free(alloc, p->UnpackPositions);
+  IAlloc_Free(alloc, p->IsDirs);
+
+  IAlloc_Free(alloc, p->FolderToFile);
+  IAlloc_Free(alloc, p->FileToFolder);
+
+  IAlloc_Free(alloc, p->FileNameOffsets);
+  IAlloc_Free(alloc, p->FileNames);
+
+  SzBitUi32s_Free(&p->CRCs, alloc);
+  SzBitUi32s_Free(&p->Attribs, alloc);
+  // SzBitUi32s_Free(&p->Parents, alloc);
+  SzBitUi64s_Free(&p->MTime, alloc);
+  SzBitUi64s_Free(&p->CTime, alloc);
+  
+  SzAr_Free(&p->db, alloc);
+  SzArEx_Init(p);
+}
+
+
+static int TestSignatureCandidate(const Byte *testBytes)
+{
+  unsigned i;
+  for (i = 0; i < k7zSignatureSize; i++)
+    if (testBytes[i] != k7zSignature[i])
+      return 0;
+  return 1;
+}
+
+#define SzData_Clear(p) { (p)->Data = NULL; (p)->Size = 0; }
+
+#define SZ_READ_BYTE_SD(_sd_, dest) if ((_sd_)->Size == 0) return SZ_ERROR_ARCHIVE; (_sd_)->Size--; dest = *(_sd_)->Data++;
+#define SZ_READ_BYTE(dest) SZ_READ_BYTE_SD(sd, dest)
+#define SZ_READ_BYTE_2(dest) if (sd.Size == 0) return SZ_ERROR_ARCHIVE; sd.Size--; dest = *sd.Data++;
+
+#define SKIP_DATA(sd, size) { sd->Size -= (size_t)(size); sd->Data += (size_t)(size); }
+#define SKIP_DATA2(sd, size) { sd.Size -= (size_t)(size); sd.Data += (size_t)(size); }
+
+#define SZ_READ_32(dest) if (sd.Size < 4) return SZ_ERROR_ARCHIVE; \
+   dest = GetUi32(sd.Data); SKIP_DATA2(sd, 4);
+
+static MY_NO_INLINE SRes ReadNumber(CSzData *sd, UInt64 *value)
+{
+  Byte firstByte, mask;
+  unsigned i;
+  UInt32 v;
+
+  SZ_READ_BYTE(firstByte);
+  if ((firstByte & 0x80) == 0)
+  {
+    *value = firstByte;
+    return SZ_OK;
+  }
+  SZ_READ_BYTE(v);
+  if ((firstByte & 0x40) == 0)
+  {
+    *value = (((UInt32)firstByte & 0x3F) << 8) | v;
+    return SZ_OK;
+  }
+  SZ_READ_BYTE(mask);
+  *value = v | ((UInt32)mask << 8);
+  mask = 0x20;
+  for (i = 2; i < 8; i++)
+  {
+    Byte b;
+    if ((firstByte & mask) == 0)
+    {
+      UInt64 highPart = (unsigned)firstByte & (unsigned)(mask - 1);
+      *value |= (highPart << (8 * i));
+      return SZ_OK;
+    }
+    SZ_READ_BYTE(b);
+    *value |= ((UInt64)b << (8 * i));
+    mask >>= 1;
+  }
+  return SZ_OK;
+}
+
+
+static MY_NO_INLINE SRes SzReadNumber32(CSzData *sd, UInt32 *value)
+{
+  Byte firstByte;
+  UInt64 value64;
+  if (sd->Size == 0)
+    return SZ_ERROR_ARCHIVE;
+  firstByte = *sd->Data;
+  if ((firstByte & 0x80) == 0)
+  {
+    *value = firstByte;
+    sd->Data++;
+    sd->Size--;
+    return SZ_OK;
+  }
+  RINOK(ReadNumber(sd, &value64));
+  if (value64 >= (UInt32)0x80000000 - 1)
+    return SZ_ERROR_UNSUPPORTED;
+  if (value64 >= ((UInt64)(1) << ((sizeof(size_t) - 1) * 8 + 4)))
+    return SZ_ERROR_UNSUPPORTED;
+  *value = (UInt32)value64;
+  return SZ_OK;
+}
+
+#define ReadID(sd, value) ReadNumber(sd, value)
+
+static SRes SkipData(CSzData *sd)
+{
+  UInt64 size;
+  RINOK(ReadNumber(sd, &size));
+  if (size > sd->Size)
+    return SZ_ERROR_ARCHIVE;
+  SKIP_DATA(sd, size);
+  return SZ_OK;
+}
+
+static SRes WaitId(CSzData *sd, UInt32 id)
+{
+  for (;;)
+  {
+    UInt64 type;
+    RINOK(ReadID(sd, &type));
+    if (type == id)
+      return SZ_OK;
+    if (type == k7zIdEnd)
+      return SZ_ERROR_ARCHIVE;
+    RINOK(SkipData(sd));
+  }
+}
+
+static SRes RememberBitVector(CSzData *sd, UInt32 numItems, const Byte **v)
+{
+  UInt32 numBytes = (numItems + 7) >> 3;
+  if (numBytes > sd->Size)
+    return SZ_ERROR_ARCHIVE;
+  *v = sd->Data;
+  SKIP_DATA(sd, numBytes);
+  return SZ_OK;
+}
+
+static UInt32 CountDefinedBits(const Byte *bits, UInt32 numItems)
+{
+  Byte b = 0;
+  unsigned m = 0;
+  UInt32 sum = 0;
+  for (; numItems != 0; numItems--)
+  {
+    if (m == 0)
+    {
+      b = *bits++;
+      m = 8;
+    }
+    m--;
+    sum += ((b >> m) & 1);
+  }
+  return sum;
+}
+
+static MY_NO_INLINE SRes ReadBitVector(CSzData *sd, UInt32 numItems, Byte **v, ISzAlloc *alloc)
+{
+  Byte allAreDefined;
+  Byte *v2;
+  UInt32 numBytes = (numItems + 7) >> 3;
+  *v = NULL;
+  SZ_READ_BYTE(allAreDefined);
+  if (numBytes == 0)
+    return SZ_OK;
+  if (allAreDefined == 0)
+  {
+    if (numBytes > sd->Size)
+      return SZ_ERROR_ARCHIVE;
+    MY_ALLOC_AND_CPY(*v, numBytes, sd->Data, alloc);
+    SKIP_DATA(sd, numBytes);
+    return SZ_OK;
+  }
+  MY_ALLOC(Byte, *v, numBytes, alloc);
+  v2 = *v;
+  memset(v2, 0xFF, (size_t)numBytes);
+  {
+    unsigned numBits = (unsigned)numItems & 7;
+    if (numBits != 0)
+      v2[numBytes - 1] = (Byte)((((UInt32)1 << numBits) - 1) << (8 - numBits));
+  }
+  return SZ_OK;
+}
+
+static MY_NO_INLINE SRes ReadUi32s(CSzData *sd2, UInt32 numItems, CSzBitUi32s *crcs, ISzAlloc *alloc)
+{
+  UInt32 i;
+  CSzData sd;
+  UInt32 *vals;
+  const Byte *defs;
+  MY_ALLOC_ZE(UInt32, crcs->Vals, numItems, alloc);
+  sd = *sd2;
+  defs = crcs->Defs;
+  vals = crcs->Vals;
+  for (i = 0; i < numItems; i++)
+    if (SzBitArray_Check(defs, i))
+    {
+      SZ_READ_32(vals[i]);
+    }
+    else
+      vals[i] = 0;
+  *sd2 = sd;
+  return SZ_OK;
+}
+
+static SRes ReadBitUi32s(CSzData *sd, UInt32 numItems, CSzBitUi32s *crcs, ISzAlloc *alloc)
+{
+  SzBitUi32s_Free(crcs, alloc);
+  RINOK(ReadBitVector(sd, numItems, &crcs->Defs, alloc));
+  return ReadUi32s(sd, numItems, crcs, alloc);
+}
+
+static SRes SkipBitUi32s(CSzData *sd, UInt32 numItems)
+{
+  Byte allAreDefined;
+  UInt32 numDefined = numItems;
+  SZ_READ_BYTE(allAreDefined);
+  if (!allAreDefined)
+  {
+    size_t numBytes = (numItems + 7) >> 3;
+    if (numBytes > sd->Size)
+      return SZ_ERROR_ARCHIVE;
+    numDefined = CountDefinedBits(sd->Data, numItems);
+    SKIP_DATA(sd, numBytes);
+  }
+  if (numDefined > (sd->Size >> 2))
+    return SZ_ERROR_ARCHIVE;
+  SKIP_DATA(sd, (size_t)numDefined * 4);
+  return SZ_OK;
+}
+
+static SRes ReadPackInfo(CSzAr *p, CSzData *sd, ISzAlloc *alloc)
+{
+  RINOK(SzReadNumber32(sd, &p->NumPackStreams));
+
+  RINOK(WaitId(sd, k7zIdSize));
+  MY_ALLOC(UInt64, p->PackPositions, (size_t)p->NumPackStreams + 1, alloc);
+  {
+    UInt64 sum = 0;
+    UInt32 i;
+    UInt32 numPackStreams = p->NumPackStreams;
+    for (i = 0; i < numPackStreams; i++)
+    {
+      UInt64 packSize;
+      p->PackPositions[i] = sum;
+      RINOK(ReadNumber(sd, &packSize));
+      sum += packSize;
+      if (sum < packSize)
+        return SZ_ERROR_ARCHIVE;
+    }
+    p->PackPositions[i] = sum;
+  }
+
+  for (;;)
+  {
+    UInt64 type;
+    RINOK(ReadID(sd, &type));
+    if (type == k7zIdEnd)
+      return SZ_OK;
+    if (type == k7zIdCRC)
+    {
+      /* CRC of packed streams is unused now */
+      RINOK(SkipBitUi32s(sd, p->NumPackStreams));
+      continue;
+    }
+    RINOK(SkipData(sd));
+  }
+}
+
+/*
+static SRes SzReadSwitch(CSzData *sd)
+{
+  Byte external;
+  RINOK(SzReadByte(sd, &external));
+  return (external == 0) ? SZ_OK: SZ_ERROR_UNSUPPORTED;
+}
+*/
+
+#define k_NumCodersStreams_in_Folder_MAX (SZ_NUM_BONDS_IN_FOLDER_MAX + SZ_NUM_PACK_STREAMS_IN_FOLDER_MAX)
+
+SRes SzGetNextFolderItem(CSzFolder *f, CSzData *sd)
+{
+  UInt32 numCoders, i;
+  UInt32 numInStreams = 0;
+  const Byte *dataStart = sd->Data;
+
+  f->NumCoders = 0;
+  f->NumBonds = 0;
+  f->NumPackStreams = 0;
+  f->UnpackStream = 0;
+  
+  RINOK(SzReadNumber32(sd, &numCoders));
+  if (numCoders == 0 || numCoders > SZ_NUM_CODERS_IN_FOLDER_MAX)
+    return SZ_ERROR_UNSUPPORTED;
+  
+  for (i = 0; i < numCoders; i++)
+  {
+    Byte mainByte;
+    CSzCoderInfo *coder = f->Coders + i;
+    unsigned idSize, j;
+    UInt64 id;
+    
+    SZ_READ_BYTE(mainByte);
+    if ((mainByte & 0xC0) != 0)
+      return SZ_ERROR_UNSUPPORTED;
+    
+    idSize = (unsigned)(mainByte & 0xF);
+    if (idSize > sizeof(id))
+      return SZ_ERROR_UNSUPPORTED;
+    if (idSize > sd->Size)
+      return SZ_ERROR_ARCHIVE;
+    id = 0;
+    for (j = 0; j < idSize; j++)
+    {
+      id = ((id << 8) | *sd->Data);
+      sd->Data++;
+      sd->Size--;
+    }
+    if (id > (UInt32)0xFFFFFFFF)
+      return SZ_ERROR_UNSUPPORTED;
+    coder->MethodID = (UInt32)id;
+    
+    coder->NumStreams = 1;
+    coder->PropsOffset = 0;
+    coder->PropsSize = 0;
+    
+    if ((mainByte & 0x10) != 0)
+    {
+      UInt32 numStreams;
+      
+      RINOK(SzReadNumber32(sd, &numStreams));
+      if (numStreams > k_NumCodersStreams_in_Folder_MAX)
+        return SZ_ERROR_UNSUPPORTED;
+      coder->NumStreams = (Byte)numStreams;
+
+      RINOK(SzReadNumber32(sd, &numStreams));
+      if (numStreams != 1)
+        return SZ_ERROR_UNSUPPORTED;
+    }
+
+    numInStreams += coder->NumStreams;
+
+    if (numInStreams > k_NumCodersStreams_in_Folder_MAX)
+      return SZ_ERROR_UNSUPPORTED;
+
+    if ((mainByte & 0x20) != 0)
+    {
+      UInt32 propsSize = 0;
+      RINOK(SzReadNumber32(sd, &propsSize));
+      if (propsSize > sd->Size)
+        return SZ_ERROR_ARCHIVE;
+      if (propsSize >= 0x80)
+        return SZ_ERROR_UNSUPPORTED;
+      coder->PropsOffset = sd->Data - dataStart;
+      coder->PropsSize = (Byte)propsSize;
+      sd->Data += (size_t)propsSize;
+      sd->Size -= (size_t)propsSize;
+    }
+  }
+
+  /*
+  if (numInStreams == 1 && numCoders == 1)
+  {
+    f->NumPackStreams = 1;
+    f->PackStreams[0] = 0;
+  }
+  else
+  */
+  {
+    Byte streamUsed[k_NumCodersStreams_in_Folder_MAX];
+    UInt32 numBonds, numPackStreams;
+    
+    numBonds = numCoders - 1;
+    if (numInStreams < numBonds)
+      return SZ_ERROR_ARCHIVE;
+    if (numBonds > SZ_NUM_BONDS_IN_FOLDER_MAX)
+      return SZ_ERROR_UNSUPPORTED;
+    f->NumBonds = numBonds;
+    
+    numPackStreams = numInStreams - numBonds;
+    if (numPackStreams > SZ_NUM_PACK_STREAMS_IN_FOLDER_MAX)
+      return SZ_ERROR_UNSUPPORTED;
+    f->NumPackStreams = numPackStreams;
+  
+    for (i = 0; i < numInStreams; i++)
+      streamUsed[i] = False;
+    
+    if (numBonds != 0)
+    {
+      Byte coderUsed[SZ_NUM_CODERS_IN_FOLDER_MAX];
+
+      for (i = 0; i < numCoders; i++)
+        coderUsed[i] = False;
+      
+      for (i = 0; i < numBonds; i++)
+      {
+        CSzBond *bp = f->Bonds + i;
+        
+        RINOK(SzReadNumber32(sd, &bp->InIndex));
+        if (bp->InIndex >= numInStreams || streamUsed[bp->InIndex])
+          return SZ_ERROR_ARCHIVE;
+        streamUsed[bp->InIndex] = True;
+        
+        RINOK(SzReadNumber32(sd, &bp->OutIndex));
+        if (bp->OutIndex >= numCoders || coderUsed[bp->OutIndex])
+          return SZ_ERROR_ARCHIVE;
+        coderUsed[bp->OutIndex] = True;
+      }
+      
+      for (i = 0; i < numCoders; i++)
+        if (!coderUsed[i])
+        {
+          f->UnpackStream = i;
+          break;
+        }
+      
+      if (i == numCoders)
+        return SZ_ERROR_ARCHIVE;
+    }
+    
+    if (numPackStreams == 1)
+    {
+      for (i = 0; i < numInStreams; i++)
+        if (!streamUsed[i])
+          break;
+      if (i == numInStreams)
+        return SZ_ERROR_ARCHIVE;
+      f->PackStreams[0] = i;
+    }
+    else
+      for (i = 0; i < numPackStreams; i++)
+      {
+        UInt32 index;
+        RINOK(SzReadNumber32(sd, &index));
+        if (index >= numInStreams || streamUsed[index])
+          return SZ_ERROR_ARCHIVE;
+        streamUsed[index] = True;
+        f->PackStreams[i] = index;
+      }
+  }
+
+  f->NumCoders = numCoders;
+
+  return SZ_OK;
+}
+
+
+static MY_NO_INLINE SRes SkipNumbers(CSzData *sd2, UInt32 num)
+{
+  CSzData sd;
+  sd = *sd2;
+  for (; num != 0; num--)
+  {
+    Byte firstByte, mask;
+    unsigned i;
+    SZ_READ_BYTE_2(firstByte);
+    if ((firstByte & 0x80) == 0)
+      continue;
+    if ((firstByte & 0x40) == 0)
+    {
+      if (sd.Size == 0)
+        return SZ_ERROR_ARCHIVE;
+      sd.Size--;
+      sd.Data++;
+      continue;
+    }
+    mask = 0x20;
+    for (i = 2; i < 8 && (firstByte & mask) != 0; i++)
+      mask >>= 1;
+    if (i > sd.Size)
+      return SZ_ERROR_ARCHIVE;
+    SKIP_DATA2(sd, i);
+  }
+  *sd2 = sd;
+  return SZ_OK;
+}
+
+
+#define k_Scan_NumCoders_MAX 64
+#define k_Scan_NumCodersStreams_in_Folder_MAX 64
+
+
+static SRes ReadUnpackInfo(CSzAr *p,
+    CSzData *sd2,
+    UInt32 numFoldersMax,
+    const CBuf *tempBufs, UInt32 numTempBufs,
+    ISzAlloc *alloc)
+{
+  CSzData sd;
+  
+  UInt32 fo, numFolders, numCodersOutStreams, packStreamIndex;
+  const Byte *startBufPtr;
+  Byte external;
+  
+  RINOK(WaitId(sd2, k7zIdFolder));
+  
+  RINOK(SzReadNumber32(sd2, &numFolders));
+  if (numFolders > numFoldersMax)
+    return SZ_ERROR_UNSUPPORTED;
+  p->NumFolders = numFolders;
+
+  SZ_READ_BYTE_SD(sd2, external);
+  if (external == 0)
+    sd = *sd2;
+  else
+  {
+    UInt32 index;
+    RINOK(SzReadNumber32(sd2, &index));
+    if (index >= numTempBufs)
+      return SZ_ERROR_ARCHIVE;
+    sd.Data = tempBufs[index].data;
+    sd.Size = tempBufs[index].size;
+  }
+  
+  MY_ALLOC(size_t, p->FoCodersOffsets, (size_t)numFolders + 1, alloc);
+  MY_ALLOC(UInt32, p->FoStartPackStreamIndex, (size_t)numFolders + 1, alloc);
+  MY_ALLOC(UInt32, p->FoToCoderUnpackSizes, (size_t)numFolders + 1, alloc);
+  MY_ALLOC(Byte, p->FoToMainUnpackSizeIndex, (size_t)numFolders, alloc);
+  
+  startBufPtr = sd.Data;
+  
+  packStreamIndex = 0;
+  numCodersOutStreams = 0;
+
+  for (fo = 0; fo < numFolders; fo++)
+  {
+    UInt32 numCoders, ci, numInStreams = 0;
+    
+    p->FoCodersOffsets[fo] = sd.Data - startBufPtr;
+    
+    RINOK(SzReadNumber32(&sd, &numCoders));
+    if (numCoders == 0 || numCoders > k_Scan_NumCoders_MAX)
+      return SZ_ERROR_UNSUPPORTED;
+    
+    for (ci = 0; ci < numCoders; ci++)
+    {
+      Byte mainByte;
+      unsigned idSize;
+      UInt32 coderInStreams;
+      
+      SZ_READ_BYTE_2(mainByte);
+      if ((mainByte & 0xC0) != 0)
+        return SZ_ERROR_UNSUPPORTED;
+      idSize = (mainByte & 0xF);
+      if (idSize > 8)
+        return SZ_ERROR_UNSUPPORTED;
+      if (idSize > sd.Size)
+        return SZ_ERROR_ARCHIVE;
+      SKIP_DATA2(sd, idSize);
+      
+      coderInStreams = 1;
+      
+      if ((mainByte & 0x10) != 0)
+      {
+        UInt32 coderOutStreams;
+        RINOK(SzReadNumber32(&sd, &coderInStreams));
+        RINOK(SzReadNumber32(&sd, &coderOutStreams));
+        if (coderInStreams > k_Scan_NumCodersStreams_in_Folder_MAX || coderOutStreams != 1)
+          return SZ_ERROR_UNSUPPORTED;
+      }
+      
+      numInStreams += coderInStreams;
+
+      if ((mainByte & 0x20) != 0)
+      {
+        UInt32 propsSize;
+        RINOK(SzReadNumber32(&sd, &propsSize));
+        if (propsSize > sd.Size)
+          return SZ_ERROR_ARCHIVE;
+        SKIP_DATA2(sd, propsSize);
+      }
+    }
+    
+    {
+      UInt32 indexOfMainStream = 0;
+      UInt32 numPackStreams = 1;
+      
+      if (numCoders != 1 || numInStreams != 1)
+      {
+        Byte streamUsed[k_Scan_NumCodersStreams_in_Folder_MAX];
+        Byte coderUsed[k_Scan_NumCoders_MAX];
+    
+        UInt32 i;
+        UInt32 numBonds = numCoders - 1;
+        if (numInStreams < numBonds)
+          return SZ_ERROR_ARCHIVE;
+        
+        if (numInStreams > k_Scan_NumCodersStreams_in_Folder_MAX)
+          return SZ_ERROR_UNSUPPORTED;
+        
+        for (i = 0; i < numInStreams; i++)
+          streamUsed[i] = False;
+        for (i = 0; i < numCoders; i++)
+          coderUsed[i] = False;
+        
+        for (i = 0; i < numBonds; i++)
+        {
+          UInt32 index;
+          
+          RINOK(SzReadNumber32(&sd, &index));
+          if (index >= numInStreams || streamUsed[index])
+            return SZ_ERROR_ARCHIVE;
+          streamUsed[index] = True;
+          
+          RINOK(SzReadNumber32(&sd, &index));
+          if (index >= numCoders || coderUsed[index])
+            return SZ_ERROR_ARCHIVE;
+          coderUsed[index] = True;
+        }
+        
+        numPackStreams = numInStreams - numBonds;
+        
+        if (numPackStreams != 1)
+          for (i = 0; i < numPackStreams; i++)
+          {
+            UInt32 index;
+            RINOK(SzReadNumber32(&sd, &index));
+            if (index >= numInStreams || streamUsed[index])
+              return SZ_ERROR_ARCHIVE;
+            streamUsed[index] = True;
+          }
+          
+        for (i = 0; i < numCoders; i++)
+          if (!coderUsed[i])
+          {
+            indexOfMainStream = i;
+            break;
+          }
+ 
+        if (i == numCoders)
+          return SZ_ERROR_ARCHIVE;
+      }
+      
+      p->FoStartPackStreamIndex[fo] = packStreamIndex;
+      p->FoToCoderUnpackSizes[fo] = numCodersOutStreams;
+      p->FoToMainUnpackSizeIndex[fo] = (Byte)indexOfMainStream;
+      numCodersOutStreams += numCoders;
+      if (numCodersOutStreams < numCoders)
+        return SZ_ERROR_UNSUPPORTED;
+      
+      packStreamIndex += numPackStreams;
+      if (packStreamIndex < numPackStreams)
+        return SZ_ERROR_UNSUPPORTED;
+      
+      if (packStreamIndex > p->NumPackStreams)
+        return SZ_ERROR_ARCHIVE;
+    }
+  }
+
+  p->FoToCoderUnpackSizes[fo] = numCodersOutStreams;
+  
+  {
+    size_t dataSize = sd.Data - startBufPtr;
+    p->FoStartPackStreamIndex[fo] = packStreamIndex;
+    p->FoCodersOffsets[fo] = dataSize;
+    MY_ALLOC_ZE_AND_CPY(p->CodersData, dataSize, startBufPtr, alloc);
+  }
+  
+  if (external != 0)
+  {
+    if (sd.Size != 0)
+      return SZ_ERROR_ARCHIVE;
+    sd = *sd2;
+  }
+  
+  RINOK(WaitId(&sd, k7zIdCodersUnpackSize));
+  
+  MY_ALLOC_ZE(UInt64, p->CoderUnpackSizes, (size_t)numCodersOutStreams, alloc);
+  {
+    UInt32 i;
+    for (i = 0; i < numCodersOutStreams; i++)
+    {
+      RINOK(ReadNumber(&sd, p->CoderUnpackSizes + i));
+    }
+  }
+
+  for (;;)
+  {
+    UInt64 type;
+    RINOK(ReadID(&sd, &type));
+    if (type == k7zIdEnd)
+    {
+      *sd2 = sd;
+      return SZ_OK;
+    }
+    if (type == k7zIdCRC)
+    {
+      RINOK(ReadBitUi32s(&sd, numFolders, &p->FolderCRCs, alloc));
+      continue;
+    }
+    RINOK(SkipData(&sd));
+  }
+}
+
+
+UInt64 SzAr_GetFolderUnpackSize(const CSzAr *p, UInt32 folderIndex)
+{
+  return p->CoderUnpackSizes[p->FoToCoderUnpackSizes[folderIndex] + p->FoToMainUnpackSizeIndex[folderIndex]];
+}
+
+
+typedef struct
+{
+  UInt32 NumTotalSubStreams;
+  UInt32 NumSubDigests;
+  CSzData sdNumSubStreams;
+  CSzData sdSizes;
+  CSzData sdCRCs;
+} CSubStreamInfo;
+
+
+static SRes ReadSubStreamsInfo(CSzAr *p, CSzData *sd, CSubStreamInfo *ssi)
+{
+  UInt64 type = 0;
+  UInt32 numSubDigests = 0;
+  UInt32 numFolders = p->NumFolders;
+  UInt32 numUnpackStreams = numFolders;
+  UInt32 numUnpackSizesInData = 0;
+
+  for (;;)
+  {
+    RINOK(ReadID(sd, &type));
+    if (type == k7zIdNumUnpackStream)
+    {
+      UInt32 i;
+      ssi->sdNumSubStreams.Data = sd->Data;
+      numUnpackStreams = 0;
+      numSubDigests = 0;
+      for (i = 0; i < numFolders; i++)
+      {
+        UInt32 numStreams;
+        RINOK(SzReadNumber32(sd, &numStreams));
+        if (numUnpackStreams > numUnpackStreams + numStreams)
+          return SZ_ERROR_UNSUPPORTED;
+        numUnpackStreams += numStreams;
+        if (numStreams != 0)
+          numUnpackSizesInData += (numStreams - 1);
+        if (numStreams != 1 || !SzBitWithVals_Check(&p->FolderCRCs, i))
+          numSubDigests += numStreams;
+      }
+      ssi->sdNumSubStreams.Size = sd->Data - ssi->sdNumSubStreams.Data;
+      continue;
+    }
+    if (type == k7zIdCRC || type == k7zIdSize || type == k7zIdEnd)
+      break;
+    RINOK(SkipData(sd));
+  }
+
+  if (!ssi->sdNumSubStreams.Data)
+  {
+    numSubDigests = numFolders;
+    if (p->FolderCRCs.Defs)
+      numSubDigests = numFolders - CountDefinedBits(p->FolderCRCs.Defs, numFolders);
+  }
+  
+  ssi->NumTotalSubStreams = numUnpackStreams;
+  ssi->NumSubDigests = numSubDigests;
+
+  if (type == k7zIdSize)
+  {
+    ssi->sdSizes.Data = sd->Data;
+    RINOK(SkipNumbers(sd, numUnpackSizesInData));
+    ssi->sdSizes.Size = sd->Data - ssi->sdSizes.Data;
+    RINOK(ReadID(sd, &type));
+  }
+
+  for (;;)
+  {
+    if (type == k7zIdEnd)
+      return SZ_OK;
+    if (type == k7zIdCRC)
+    {
+      ssi->sdCRCs.Data = sd->Data;
+      RINOK(SkipBitUi32s(sd, numSubDigests));
+      ssi->sdCRCs.Size = sd->Data - ssi->sdCRCs.Data;
+    }
+    else
+    {
+      RINOK(SkipData(sd));
+    }
+    RINOK(ReadID(sd, &type));
+  }
+}
+
+static SRes SzReadStreamsInfo(CSzAr *p,
+    CSzData *sd,
+    UInt32 numFoldersMax, const CBuf *tempBufs, UInt32 numTempBufs,
+    UInt64 *dataOffset,
+    CSubStreamInfo *ssi,
+    ISzAlloc *alloc)
+{
+  UInt64 type;
+
+  SzData_Clear(&ssi->sdSizes);
+  SzData_Clear(&ssi->sdCRCs);
+  SzData_Clear(&ssi->sdNumSubStreams);
+
+  *dataOffset = 0;
+  RINOK(ReadID(sd, &type));
+  if (type == k7zIdPackInfo)
+  {
+    RINOK(ReadNumber(sd, dataOffset));
+    RINOK(ReadPackInfo(p, sd, alloc));
+    RINOK(ReadID(sd, &type));
+  }
+  if (type == k7zIdUnpackInfo)
+  {
+    RINOK(ReadUnpackInfo(p, sd, numFoldersMax, tempBufs, numTempBufs, alloc));
+    RINOK(ReadID(sd, &type));
+  }
+  if (type == k7zIdSubStreamsInfo)
+  {
+    RINOK(ReadSubStreamsInfo(p, sd, ssi));
+    RINOK(ReadID(sd, &type));
+  }
+  else
+  {
+    ssi->NumTotalSubStreams = p->NumFolders;
+    // ssi->NumSubDigests = 0;
+  }
+
+  return (type == k7zIdEnd ? SZ_OK : SZ_ERROR_UNSUPPORTED);
+}
+
+static SRes SzReadAndDecodePackedStreams(
+    ILookInStream *inStream,
+    CSzData *sd,
+    CBuf *tempBufs,
+    UInt32 numFoldersMax,
+    UInt64 baseOffset,
+    CSzAr *p,
+    ISzAlloc *allocTemp)
+{
+  UInt64 dataStartPos;
+  UInt32 fo;
+  CSubStreamInfo ssi;
+
+  RINOK(SzReadStreamsInfo(p, sd, numFoldersMax, NULL, 0, &dataStartPos, &ssi, allocTemp));
+  
+  dataStartPos += baseOffset;
+  if (p->NumFolders == 0)
+    return SZ_ERROR_ARCHIVE;
+ 
+  for (fo = 0; fo < p->NumFolders; fo++)
+    Buf_Init(tempBufs + fo);
+  
+  for (fo = 0; fo < p->NumFolders; fo++)
+  {
+    CBuf *tempBuf = tempBufs + fo;
+    UInt64 unpackSize = SzAr_GetFolderUnpackSize(p, fo);
+    if ((size_t)unpackSize != unpackSize)
+      return SZ_ERROR_MEM;
+    if (!Buf_Create(tempBuf, (size_t)unpackSize, allocTemp))
+      return SZ_ERROR_MEM;
+  }
+  
+  for (fo = 0; fo < p->NumFolders; fo++)
+  {
+    const CBuf *tempBuf = tempBufs + fo;
+    RINOK(LookInStream_SeekTo(inStream, dataStartPos));
+    RINOK(SzAr_DecodeFolder(p, fo, inStream, dataStartPos, tempBuf->data, tempBuf->size, allocTemp));
+  }
+  
+  return SZ_OK;
+}
+
+static SRes SzReadFileNames(const Byte *data, size_t size, UInt32 numFiles, size_t *offsets)
+{
+  size_t pos = 0;
+  *offsets++ = 0;
+  if (numFiles == 0)
+    return (size == 0) ? SZ_OK : SZ_ERROR_ARCHIVE;
+  if (size < 2)
+    return SZ_ERROR_ARCHIVE;
+  if (data[size - 2] != 0 || data[size - 1] != 0)
+    return SZ_ERROR_ARCHIVE;
+  do
+  {
+    const Byte *p;
+    if (pos == size)
+      return SZ_ERROR_ARCHIVE;
+    for (p = data + pos;
+      #ifdef _WIN32
+      *(const UInt16 *)p != 0
+      #else
+      p[0] != 0 || p[1] != 0
+      #endif
+      ; p += 2);
+    pos = p - data + 2;
+    *offsets++ = (pos >> 1);
+  }
+  while (--numFiles);
+  return (pos == size) ? SZ_OK : SZ_ERROR_ARCHIVE;
+}
+
+static MY_NO_INLINE SRes ReadTime(CSzBitUi64s *p, UInt32 num,
+    CSzData *sd2,
+    const CBuf *tempBufs, UInt32 numTempBufs,
+    ISzAlloc *alloc)
+{
+  CSzData sd;
+  UInt32 i;
+  CNtfsFileTime *vals;
+  Byte *defs;
+  Byte external;
+  
+  RINOK(ReadBitVector(sd2, num, &p->Defs, alloc));
+  
+  SZ_READ_BYTE_SD(sd2, external);
+  if (external == 0)
+    sd = *sd2;
+  else
+  {
+    UInt32 index;
+    RINOK(SzReadNumber32(sd2, &index));
+    if (index >= numTempBufs)
+      return SZ_ERROR_ARCHIVE;
+    sd.Data = tempBufs[index].data;
+    sd.Size = tempBufs[index].size;
+  }
+  
+  MY_ALLOC_ZE(CNtfsFileTime, p->Vals, num, alloc);
+  vals = p->Vals;
+  defs = p->Defs;
+  for (i = 0; i < num; i++)
+    if (SzBitArray_Check(defs, i))
+    {
+      if (sd.Size < 8)
+        return SZ_ERROR_ARCHIVE;
+      vals[i].Low = GetUi32(sd.Data);
+      vals[i].High = GetUi32(sd.Data + 4);
+      SKIP_DATA2(sd, 8);
+    }
+    else
+      vals[i].High = vals[i].Low = 0;
+  
+  if (external == 0)
+    *sd2 = sd;
+  
+  return SZ_OK;
+}
+
+
+#define NUM_ADDITIONAL_STREAMS_MAX 8
+
+
+static SRes SzReadHeader2(
+    CSzArEx *p,   /* allocMain */
+    CSzData *sd,
+    ILookInStream *inStream,
+    CBuf *tempBufs, UInt32 *numTempBufs,
+    ISzAlloc *allocMain,
+    ISzAlloc *allocTemp
+    )
+{
+  UInt64 type;
+  UInt32 numFiles = 0;
+  UInt32 numEmptyStreams = 0;
+  CSubStreamInfo ssi;
+  const Byte *emptyStreams = NULL;
+  const Byte *emptyFiles = NULL;
+
+  SzData_Clear(&ssi.sdSizes);
+  SzData_Clear(&ssi.sdCRCs);
+  SzData_Clear(&ssi.sdNumSubStreams);
+
+  ssi.NumSubDigests = 0;
+  ssi.NumTotalSubStreams = 0;
+
+  RINOK(ReadID(sd, &type));
+
+  if (type == k7zIdArchiveProperties)
+  {
+    for (;;)
+    {
+      UInt64 type;
+      RINOK(ReadID(sd, &type));
+      if (type == k7zIdEnd)
+        break;
+      RINOK(SkipData(sd));
+    }
+    RINOK(ReadID(sd, &type));
+  }
+
+  if (type == k7zIdAdditionalStreamsInfo)
+  {
+    CSzAr tempAr;
+    SRes res;
+    
+    SzAr_Init(&tempAr);
+    res = SzReadAndDecodePackedStreams(inStream, sd, tempBufs, NUM_ADDITIONAL_STREAMS_MAX,
+        p->startPosAfterHeader, &tempAr, allocTemp);
+    *numTempBufs = tempAr.NumFolders;
+    SzAr_Free(&tempAr, allocTemp);
+    
+    if (res != SZ_OK)
+      return res;
+    RINOK(ReadID(sd, &type));
+  }
+
+  if (type == k7zIdMainStreamsInfo)
+  {
+    RINOK(SzReadStreamsInfo(&p->db, sd, (UInt32)1 << 30, tempBufs, *numTempBufs,
+        &p->dataPos, &ssi, allocMain));
+    p->dataPos += p->startPosAfterHeader;
+    RINOK(ReadID(sd, &type));
+  }
+
+  if (type == k7zIdEnd)
+  {
+    return SZ_OK;
+  }
+
+  if (type != k7zIdFilesInfo)
+    return SZ_ERROR_ARCHIVE;
+  
+  RINOK(SzReadNumber32(sd, &numFiles));
+  p->NumFiles = numFiles;
+
+  for (;;)
+  {
+    UInt64 type;
+    UInt64 size;
+    RINOK(ReadID(sd, &type));
+    if (type == k7zIdEnd)
+      break;
+    RINOK(ReadNumber(sd, &size));
+    if (size > sd->Size)
+      return SZ_ERROR_ARCHIVE;
+    
+    if (type >= ((UInt32)1 << 8))
+    {
+      SKIP_DATA(sd, size);
+    }
+    else switch ((unsigned)type)
+    {
+      case k7zIdName:
+      {
+        size_t namesSize;
+        const Byte *namesData;
+        Byte external;
+
+        SZ_READ_BYTE(external);
+        if (external == 0)
+        {
+          namesSize = (size_t)size - 1;
+          namesData = sd->Data;
+        }
+        else
+        {
+          UInt32 index;
+          RINOK(SzReadNumber32(sd, &index));
+          if (index >= *numTempBufs)
+            return SZ_ERROR_ARCHIVE;
+          namesData = (tempBufs)[index].data;
+          namesSize = (tempBufs)[index].size;
+        }
+
+        if ((namesSize & 1) != 0)
+          return SZ_ERROR_ARCHIVE;
+        MY_ALLOC(size_t, p->FileNameOffsets, numFiles + 1, allocMain);
+        MY_ALLOC_ZE_AND_CPY(p->FileNames, namesSize, namesData, allocMain);
+        RINOK(SzReadFileNames(p->FileNames, namesSize, numFiles, p->FileNameOffsets))
+        if (external == 0)
+        {
+          SKIP_DATA(sd, namesSize);
+        }
+        break;
+      }
+      case k7zIdEmptyStream:
+      {
+        RINOK(RememberBitVector(sd, numFiles, &emptyStreams));
+        numEmptyStreams = CountDefinedBits(emptyStreams, numFiles);
+        emptyFiles = NULL;
+        break;
+      }
+      case k7zIdEmptyFile:
+      {
+        RINOK(RememberBitVector(sd, numEmptyStreams, &emptyFiles));
+        break;
+      }
+      case k7zIdWinAttrib:
+      {
+        Byte external;
+        CSzData sdSwitch;
+        CSzData *sdPtr;
+        SzBitUi32s_Free(&p->Attribs, allocMain);
+        RINOK(ReadBitVector(sd, numFiles, &p->Attribs.Defs, allocMain));
+
+        SZ_READ_BYTE(external);
+        if (external == 0)
+          sdPtr = sd;
+        else
+        {
+          UInt32 index;
+          RINOK(SzReadNumber32(sd, &index));
+          if (index >= *numTempBufs)
+            return SZ_ERROR_ARCHIVE;
+          sdSwitch.Data = (tempBufs)[index].data;
+          sdSwitch.Size = (tempBufs)[index].size;
+          sdPtr = &sdSwitch;
+        }
+        RINOK(ReadUi32s(sdPtr, numFiles, &p->Attribs, allocMain));
+        break;
+      }
+      /*
+      case k7zParent:
+      {
+        SzBitUi32s_Free(&p->Parents, allocMain);
+        RINOK(ReadBitVector(sd, numFiles, &p->Parents.Defs, allocMain));
+        RINOK(SzReadSwitch(sd));
+        RINOK(ReadUi32s(sd, numFiles, &p->Parents, allocMain));
+        break;
+      }
+      */
+      case k7zIdMTime: RINOK(ReadTime(&p->MTime, numFiles, sd, tempBufs, *numTempBufs, allocMain)); break;
+      case k7zIdCTime: RINOK(ReadTime(&p->CTime, numFiles, sd, tempBufs, *numTempBufs, allocMain)); break;
+      default:
+      {
+        SKIP_DATA(sd, size);
+      }
+    }
+  }
+
+  if (numFiles - numEmptyStreams != ssi.NumTotalSubStreams)
+    return SZ_ERROR_ARCHIVE;
+
+  for (;;)
+  {
+    UInt64 type;
+    RINOK(ReadID(sd, &type));
+    if (type == k7zIdEnd)
+      break;
+    RINOK(SkipData(sd));
+  }
+
+  {
+    UInt32 i;
+    UInt32 emptyFileIndex = 0;
+    UInt32 folderIndex = 0;
+    UInt32 remSubStreams = 0;
+    UInt32 numSubStreams = 0;
+    UInt64 unpackPos = 0;
+    const Byte *digestsDefs = NULL;
+    const Byte *digestsVals = NULL;
+    UInt32 digestsValsIndex = 0;
+    UInt32 digestIndex;
+    Byte allDigestsDefined = 0;
+    Byte isDirMask = 0;
+    Byte crcMask = 0;
+    Byte mask = 0x80;
+    
+    MY_ALLOC(UInt32, p->FolderToFile, p->db.NumFolders + 1, allocMain);
+    MY_ALLOC_ZE(UInt32, p->FileToFolder, p->NumFiles, allocMain);
+    MY_ALLOC(UInt64, p->UnpackPositions, p->NumFiles + 1, allocMain);
+    MY_ALLOC_ZE(Byte, p->IsDirs, (p->NumFiles + 7) >> 3, allocMain);
+
+    RINOK(SzBitUi32s_Alloc(&p->CRCs, p->NumFiles, allocMain));
+
+    if (ssi.sdCRCs.Size != 0)
+    {
+      SZ_READ_BYTE_SD(&ssi.sdCRCs, allDigestsDefined);
+      if (allDigestsDefined)
+        digestsVals = ssi.sdCRCs.Data;
+      else
+      {
+        size_t numBytes = (ssi.NumSubDigests + 7) >> 3;
+        digestsDefs = ssi.sdCRCs.Data;
+        digestsVals = digestsDefs + numBytes;
+      }
+    }
+
+    digestIndex = 0;
+    
+    for (i = 0; i < numFiles; i++, mask >>= 1)
+    {
+      if (mask == 0)
+      {
+        UInt32 byteIndex = (i - 1) >> 3;
+        p->IsDirs[byteIndex] = isDirMask;
+        p->CRCs.Defs[byteIndex] = crcMask;
+        isDirMask = 0;
+        crcMask = 0;
+        mask = 0x80;
+      }
+
+      p->UnpackPositions[i] = unpackPos;
+      p->CRCs.Vals[i] = 0;
+      
+      if (emptyStreams && SzBitArray_Check(emptyStreams, i))
+      {
+        if (emptyFiles)
+        {
+          if (!SzBitArray_Check(emptyFiles, emptyFileIndex))
+            isDirMask |= mask;
+          emptyFileIndex++;
+        }
+        else
+          isDirMask |= mask;
+        if (remSubStreams == 0)
+        {
+          p->FileToFolder[i] = (UInt32)-1;
+          continue;
+        }
+      }
+      
+      if (remSubStreams == 0)
+      {
+        for (;;)
+        {
+          if (folderIndex >= p->db.NumFolders)
+            return SZ_ERROR_ARCHIVE;
+          p->FolderToFile[folderIndex] = i;
+          numSubStreams = 1;
+          if (ssi.sdNumSubStreams.Data)
+          {
+            RINOK(SzReadNumber32(&ssi.sdNumSubStreams, &numSubStreams));
+          }
+          remSubStreams = numSubStreams;
+          if (numSubStreams != 0)
+            break;
+          {
+            UInt64 folderUnpackSize = SzAr_GetFolderUnpackSize(&p->db, folderIndex);
+            unpackPos += folderUnpackSize;
+            if (unpackPos < folderUnpackSize)
+              return SZ_ERROR_ARCHIVE;
+          }
+
+          folderIndex++;
+        }
+      }
+      
+      p->FileToFolder[i] = folderIndex;
+      
+      if (emptyStreams && SzBitArray_Check(emptyStreams, i))
+        continue;
+      
+      if (--remSubStreams == 0)
+      {
+        UInt64 folderUnpackSize = SzAr_GetFolderUnpackSize(&p->db, folderIndex);
+        UInt64 startFolderUnpackPos = p->UnpackPositions[p->FolderToFile[folderIndex]];
+        if (folderUnpackSize < unpackPos - startFolderUnpackPos)
+          return SZ_ERROR_ARCHIVE;
+        unpackPos = startFolderUnpackPos + folderUnpackSize;
+        if (unpackPos < folderUnpackSize)
+          return SZ_ERROR_ARCHIVE;
+
+        if (numSubStreams == 1 && SzBitWithVals_Check(&p->db.FolderCRCs, i))
+        {
+          p->CRCs.Vals[i] = p->db.FolderCRCs.Vals[folderIndex];
+          crcMask |= mask;
+        }
+        else if (allDigestsDefined || (digestsDefs && SzBitArray_Check(digestsDefs, digestIndex)))
+        {
+          p->CRCs.Vals[i] = GetUi32(digestsVals + (size_t)digestsValsIndex * 4);
+          digestsValsIndex++;
+          crcMask |= mask;
+        }
+        
+        folderIndex++;
+      }
+      else
+      {
+        UInt64 v;
+        RINOK(ReadNumber(&ssi.sdSizes, &v));
+        unpackPos += v;
+        if (unpackPos < v)
+          return SZ_ERROR_ARCHIVE;
+        if (allDigestsDefined || (digestsDefs && SzBitArray_Check(digestsDefs, digestIndex)))
+        {
+          p->CRCs.Vals[i] = GetUi32(digestsVals + (size_t)digestsValsIndex * 4);
+          digestsValsIndex++;
+          crcMask |= mask;
+        }
+      }
+    }
+
+    if (mask != 0x80)
+    {
+      UInt32 byteIndex = (i - 1) >> 3;
+      p->IsDirs[byteIndex] = isDirMask;
+      p->CRCs.Defs[byteIndex] = crcMask;
+    }
+    
+    p->UnpackPositions[i] = unpackPos;
+
+    if (remSubStreams != 0)
+      return SZ_ERROR_ARCHIVE;
+
+    for (;;)
+    {
+      p->FolderToFile[folderIndex] = i;
+      if (folderIndex >= p->db.NumFolders)
+        break;
+      if (!ssi.sdNumSubStreams.Data)
+        return SZ_ERROR_ARCHIVE;
+      RINOK(SzReadNumber32(&ssi.sdNumSubStreams, &numSubStreams));
+      if (numSubStreams != 0)
+        return SZ_ERROR_ARCHIVE;
+      /*
+      {
+        UInt64 folderUnpackSize = SzAr_GetFolderUnpackSize(&p->db, folderIndex);
+        unpackPos += folderUnpackSize;
+        if (unpackPos < folderUnpackSize)
+          return SZ_ERROR_ARCHIVE;
+      }
+      */
+      folderIndex++;
+    }
+
+    if (ssi.sdNumSubStreams.Data && ssi.sdNumSubStreams.Size != 0)
+      return SZ_ERROR_ARCHIVE;
+  }
+  
+  return SZ_OK;
+}
+
+
+static SRes SzReadHeader(
+    CSzArEx *p,
+    CSzData *sd,
+    ILookInStream *inStream,
+    ISzAlloc *allocMain,
+    ISzAlloc *allocTemp)
+{
+  UInt32 i;
+  UInt32 numTempBufs = 0;
+  SRes res;
+  CBuf tempBufs[NUM_ADDITIONAL_STREAMS_MAX];
+
+  for (i = 0; i < NUM_ADDITIONAL_STREAMS_MAX; i++)
+    Buf_Init(tempBufs + i);
+  
+  res = SzReadHeader2(p, sd, inStream,
+      tempBufs, &numTempBufs,
+      allocMain, allocTemp);
+  
+  for (i = 0; i < NUM_ADDITIONAL_STREAMS_MAX; i++)
+    Buf_Free(tempBufs + i, allocTemp);
+
+  RINOK(res);
+
+  if (sd->Size != 0)
+    return SZ_ERROR_FAIL;
+
+  return res;
+}
+
+static SRes SzArEx_Open2(
+    CSzArEx *p,
+    ILookInStream *inStream,
+    ISzAlloc *allocMain,
+    ISzAlloc *allocTemp)
+{
+  Byte header[k7zStartHeaderSize];
+  Int64 startArcPos;
+  UInt64 nextHeaderOffset, nextHeaderSize;
+  size_t nextHeaderSizeT;
+  UInt32 nextHeaderCRC;
+  CBuf buf;
+  SRes res;
+
+  startArcPos = 0;
+  RINOK(inStream->Seek(inStream, &startArcPos, SZ_SEEK_CUR));
+
+  RINOK(LookInStream_Read2(inStream, header, k7zStartHeaderSize, SZ_ERROR_NO_ARCHIVE));
+
+  if (!TestSignatureCandidate(header))
+    return SZ_ERROR_NO_ARCHIVE;
+  if (header[6] != k7zMajorVersion)
+    return SZ_ERROR_UNSUPPORTED;
+
+  nextHeaderOffset = GetUi64(header + 12);
+  nextHeaderSize = GetUi64(header + 20);
+  nextHeaderCRC = GetUi32(header + 28);
+
+  p->startPosAfterHeader = startArcPos + k7zStartHeaderSize;
+  
+  if (CrcCalc(header + 12, 20) != GetUi32(header + 8))
+    return SZ_ERROR_CRC;
+
+  nextHeaderSizeT = (size_t)nextHeaderSize;
+  if (nextHeaderSizeT != nextHeaderSize)
+    return SZ_ERROR_MEM;
+  if (nextHeaderSizeT == 0)
+    return SZ_OK;
+  if (nextHeaderOffset > nextHeaderOffset + nextHeaderSize ||
+      nextHeaderOffset > nextHeaderOffset + nextHeaderSize + k7zStartHeaderSize)
+    return SZ_ERROR_NO_ARCHIVE;
+
+  {
+    Int64 pos = 0;
+    RINOK(inStream->Seek(inStream, &pos, SZ_SEEK_END));
+    if ((UInt64)pos < startArcPos + nextHeaderOffset ||
+        (UInt64)pos < startArcPos + k7zStartHeaderSize + nextHeaderOffset ||
+        (UInt64)pos < startArcPos + k7zStartHeaderSize + nextHeaderOffset + nextHeaderSize)
+      return SZ_ERROR_INPUT_EOF;
+  }
+
+  RINOK(LookInStream_SeekTo(inStream, startArcPos + k7zStartHeaderSize + nextHeaderOffset));
+
+  if (!Buf_Create(&buf, nextHeaderSizeT, allocTemp))
+    return SZ_ERROR_MEM;
+
+  res = LookInStream_Read(inStream, buf.data, nextHeaderSizeT);
+  
+  if (res == SZ_OK)
+  {
+    res = SZ_ERROR_ARCHIVE;
+    if (CrcCalc(buf.data, nextHeaderSizeT) == nextHeaderCRC)
+    {
+      CSzData sd;
+      UInt64 type;
+      sd.Data = buf.data;
+      sd.Size = buf.size;
+      
+      res = ReadID(&sd, &type);
+      
+      if (res == SZ_OK && type == k7zIdEncodedHeader)
+      {
+        CSzAr tempAr;
+        CBuf tempBuf;
+        Buf_Init(&tempBuf);
+        
+        SzAr_Init(&tempAr);
+        res = SzReadAndDecodePackedStreams(inStream, &sd, &tempBuf, 1, p->startPosAfterHeader, &tempAr, allocTemp);
+        SzAr_Free(&tempAr, allocTemp);
+       
+        if (res != SZ_OK)
+        {
+          Buf_Free(&tempBuf, allocTemp);
+        }
+        else
+        {
+          Buf_Free(&buf, allocTemp);
+          buf.data = tempBuf.data;
+          buf.size = tempBuf.size;
+          sd.Data = buf.data;
+          sd.Size = buf.size;
+          res = ReadID(&sd, &type);
+        }
+      }
+  
+      if (res == SZ_OK)
+      {
+        if (type == k7zIdHeader)
+        {
+          /*
+          CSzData sd2;
+          unsigned ttt;
+          for (ttt = 0; ttt < 40000; ttt++)
+          {
+            SzArEx_Free(p, allocMain);
+            sd2 = sd;
+            res = SzReadHeader(p, &sd2, inStream, allocMain, allocTemp);
+            if (res != SZ_OK)
+              break;
+          }
+          */
+          res = SzReadHeader(p, &sd, inStream, allocMain, allocTemp);
+        }
+        else
+          res = SZ_ERROR_UNSUPPORTED;
+      }
+    }
+  }
+ 
+  Buf_Free(&buf, allocTemp);
+  return res;
+}
+
+
+SRes SzArEx_Open(CSzArEx *p, ILookInStream *inStream,
+    ISzAlloc *allocMain, ISzAlloc *allocTemp)
+{
+  SRes res = SzArEx_Open2(p, inStream, allocMain, allocTemp);
+  if (res != SZ_OK)
+    SzArEx_Free(p, allocMain);
+  return res;
+}
+
+
+SRes SzArEx_Extract(
+    const CSzArEx *p,
+    ILookInStream *inStream,
+    UInt32 fileIndex,
+    UInt32 *blockIndex,
+    Byte **tempBuf,
+    size_t *outBufferSize,
+    size_t *offset,
+    size_t *outSizeProcessed,
+    ISzAlloc *allocMain,
+    ISzAlloc *allocTemp)
+{
+  UInt32 folderIndex = p->FileToFolder[fileIndex];
+  SRes res = SZ_OK;
+  
+  *offset = 0;
+  *outSizeProcessed = 0;
+  
+  if (folderIndex == (UInt32)-1)
+  {
+    IAlloc_Free(allocMain, *tempBuf);
+    *blockIndex = folderIndex;
+    *tempBuf = NULL;
+    *outBufferSize = 0;
+    return SZ_OK;
+  }
+
+  if (*tempBuf == NULL || *blockIndex != folderIndex)
+  {
+    UInt64 unpackSizeSpec = SzAr_GetFolderUnpackSize(&p->db, folderIndex);
+    /*
+    UInt64 unpackSizeSpec =
+        p->UnpackPositions[p->FolderToFile[folderIndex + 1]] -
+        p->UnpackPositions[p->FolderToFile[folderIndex]];
+    */
+    size_t unpackSize = (size_t)unpackSizeSpec;
+
+    if (unpackSize != unpackSizeSpec)
+      return SZ_ERROR_MEM;
+    *blockIndex = folderIndex;
+    IAlloc_Free(allocMain, *tempBuf);
+    *tempBuf = NULL;
+    
+    if (res == SZ_OK)
+    {
+      *outBufferSize = unpackSize;
+      if (unpackSize != 0)
+      {
+        *tempBuf = (Byte *)IAlloc_Alloc(allocMain, unpackSize);
+        if (*tempBuf == NULL)
+          res = SZ_ERROR_MEM;
+      }
+  
+      if (res == SZ_OK)
+      {
+        res = SzAr_DecodeFolder(&p->db, folderIndex,
+            inStream, p->dataPos, *tempBuf, unpackSize, allocTemp);
+      }
+    }
+  }
+
+  if (res == SZ_OK)
+  {
+    UInt64 unpackPos = p->UnpackPositions[fileIndex];
+    *offset = (size_t)(unpackPos - p->UnpackPositions[p->FolderToFile[folderIndex]]);
+    *outSizeProcessed = (size_t)(p->UnpackPositions[fileIndex + 1] - unpackPos);
+    if (*offset + *outSizeProcessed > *outBufferSize)
+      return SZ_ERROR_FAIL;
+    if (SzBitWithVals_Check(&p->CRCs, fileIndex))
+      if (CrcCalc(*tempBuf + *offset, *outSizeProcessed) != p->CRCs.Vals[fileIndex])
+        res = SZ_ERROR_CRC;
+  }
+
+  return res;
+}
+
+
+size_t SzArEx_GetFileNameUtf16(const CSzArEx *p, size_t fileIndex, UInt16 *dest)
+{
+  size_t offs = p->FileNameOffsets[fileIndex];
+  size_t len = p->FileNameOffsets[fileIndex + 1] - offs;
+  if (dest != 0)
+  {
+    size_t i;
+    const Byte *src = p->FileNames + offs * 2;
+    for (i = 0; i < len; i++)
+      dest[i] = GetUi16(src + i * 2);
+  }
+  return len;
+}
+
+/*
+size_t SzArEx_GetFullNameLen(const CSzArEx *p, size_t fileIndex)
+{
+  size_t len;
+  if (!p->FileNameOffsets)
+    return 1;
+  len = 0;
+  for (;;)
+  {
+    UInt32 parent = (UInt32)(Int32)-1;
+    len += p->FileNameOffsets[fileIndex + 1] - p->FileNameOffsets[fileIndex];
+    if SzBitWithVals_Check(&p->Parents, fileIndex)
+      parent = p->Parents.Vals[fileIndex];
+    if (parent == (UInt32)(Int32)-1)
+      return len;
+    fileIndex = parent;
+  }
+}
+
+UInt16 *SzArEx_GetFullNameUtf16_Back(const CSzArEx *p, size_t fileIndex, UInt16 *dest)
+{
+  Bool needSlash;
+  if (!p->FileNameOffsets)
+  {
+    *(--dest) = 0;
+    return dest;
+  }
+  needSlash = False;
+  for (;;)
+  {
+    UInt32 parent = (UInt32)(Int32)-1;
+    size_t curLen = p->FileNameOffsets[fileIndex + 1] - p->FileNameOffsets[fileIndex];
+    SzArEx_GetFileNameUtf16(p, fileIndex, dest - curLen);
+    if (needSlash)
+      *(dest - 1) = '/';
+    needSlash = True;
+    dest -= curLen;
+
+    if SzBitWithVals_Check(&p->Parents, fileIndex)
+      parent = p->Parents.Vals[fileIndex];
+    if (parent == (UInt32)(Int32)-1)
+      return dest;
+    fileIndex = parent;
+  }
+}
+*/