private void ReadEndOfCentralDirectory()
{
try
{
this._archiveStream.Seek(-18L, SeekOrigin.End);
if (!ZipHelper.SeekBackwardsToSignature(this._archiveStream, 101010256U))
{
throw new InvalidDataException(CompressionConstants.EOCDNotFound);
}
long position = this._archiveStream.Position;
ZipEndOfCentralDirectoryBlock eocdBlock;
ZipEndOfCentralDirectoryBlock.TryReadBlock(this._archiveReader, out eocdBlock);
if ((int)eocdBlock.NumberOfThisDisk != (int)eocdBlock.NumberOfTheDiskWithTheStartOfTheCentralDirectory)
{
throw new InvalidDataException(CompressionConstants.SplitSpanned);
}
this._numberOfThisDisk = (uint)eocdBlock.NumberOfThisDisk;
this._centralDirectoryStart = (long)eocdBlock.OffsetOfStartOfCentralDirectoryWithRespectToTheStartingDiskNumber;
if ((int)eocdBlock.NumberOfEntriesInTheCentralDirectory != (int)eocdBlock.NumberOfEntriesInTheCentralDirectoryOnThisDisk)
{
throw new InvalidDataException(CompressionConstants.SplitSpanned);
}
this._expectedNumberOfEntries = (long)eocdBlock.NumberOfEntriesInTheCentralDirectory;
if (this._mode == ZipArchiveMode.Update)
{
this._archiveComment = eocdBlock.ArchiveComment;
}
if ((int)eocdBlock.NumberOfThisDisk == (int)ushort.MaxValue || (int)eocdBlock.OffsetOfStartOfCentralDirectoryWithRespectToTheStartingDiskNumber == -1 || (int)eocdBlock.NumberOfEntriesInTheCentralDirectory == (int)ushort.MaxValue)
{
this._archiveStream.Seek(position - 16L, SeekOrigin.Begin);
if (ZipHelper.SeekBackwardsToSignature(this._archiveStream, 117853008U))
{
Zip64EndOfCentralDirectoryLocator zip64EOCDLocator;
Zip64EndOfCentralDirectoryLocator.TryReadBlock(this._archiveReader, out zip64EOCDLocator);
if (zip64EOCDLocator.OffsetOfZip64EOCD > 9223372036854775807UL)
{
throw new InvalidDataException(CompressionConstants.FieldTooBigOffsetToZip64EOCD);
}
this._archiveStream.Seek((long)zip64EOCDLocator.OffsetOfZip64EOCD, SeekOrigin.Begin);
Zip64EndOfCentralDirectoryRecord zip64EOCDRecord;
if (!Zip64EndOfCentralDirectoryRecord.TryReadBlock(this._archiveReader, out zip64EOCDRecord))
{
throw new InvalidDataException(CompressionConstants.Zip64EOCDNotWhereExpected);
}
this._numberOfThisDisk = zip64EOCDRecord.NumberOfThisDisk;
if (zip64EOCDRecord.NumberOfEntriesTotal > 9223372036854775807UL)
{
throw new InvalidDataException(CompressionConstants.FieldTooBigNumEntries);
}
if (zip64EOCDRecord.OffsetOfCentralDirectory > 9223372036854775807UL)
{
throw new InvalidDataException(CompressionConstants.FieldTooBigOffsetToCD);
}
if ((long)zip64EOCDRecord.NumberOfEntriesTotal != (long)zip64EOCDRecord.NumberOfEntriesOnThisDisk)
{
throw new InvalidDataException(CompressionConstants.SplitSpanned);
}
this._expectedNumberOfEntries = (long)zip64EOCDRecord.NumberOfEntriesTotal;
this._centralDirectoryStart = (long)zip64EOCDRecord.OffsetOfCentralDirectory;
}
}
if (this._centralDirectoryStart > this._archiveStream.Length)
{
throw new InvalidDataException(CompressionConstants.FieldTooBigOffsetToCD);
}
}
catch (EndOfStreamException ex)
{
throw new InvalidDataException(CompressionConstants.CDCorrupt, (Exception)ex);
}
catch (IOException ex)
{
throw new InvalidDataException(CompressionConstants.CDCorrupt, (Exception)ex);
}
}