internal void UpdatePadding(long size)
{
if (Math.Abs(size) <= 0xffffL)
{
if ((size > 0L) && (this._paddingElement != null))
{
if (this._paddingElement.PaddingSize >= size)
{
this._paddingElement.PaddingSize = (ushort)(this._paddingElement.PaddingSize - ((ushort)size));
}
else if (this._paddingElement.Size == size)
{
this._paddingElement = null;
}
}
else if (size < 0L)
{
if (this._paddingElement == null)
{
size += ZipIOExtraFieldPaddingElement.MinimumFieldDataSize + ZipIOExtraFieldElement.MinimumSize;
if (size >= 0L)
{
this._paddingElement = new ZipIOExtraFieldPaddingElement();
this._paddingElement.PaddingSize = (ushort)size;
}
}
else if ((this._paddingElement.PaddingSize - size) <= 0xffffL)
{
this._paddingElement.PaddingSize = (ushort)(this._paddingElement.PaddingSize - size);
}
}
}
}
internal static ZipIOExtraField ParseRecord(BinaryReader reader, ZipIOZip64ExtraFieldUsage zip64extraFieldUsage, ushort expectedExtraFieldSize)
{
if (expectedExtraFieldSize == 0)
{
if (zip64extraFieldUsage != ZipIOZip64ExtraFieldUsage.None)
{
throw new FileFormatException(SR.Get("CorruptedData"));
}
return(CreateNew(false));
}
ZipIOExtraField field = new ZipIOExtraField();
while (expectedExtraFieldSize > 0)
{
if (expectedExtraFieldSize < ZipIOExtraFieldElement.MinimumSize)
{
throw new FileFormatException(SR.Get("CorruptedData"));
}
ZipIOExtraFieldElement element = ZipIOExtraFieldElement.Parse(reader, zip64extraFieldUsage);
ZipIOExtraFieldZip64Element element3 = element as ZipIOExtraFieldZip64Element;
ZipIOExtraFieldPaddingElement element2 = element as ZipIOExtraFieldPaddingElement;
if (element3 != null)
{
if (field._zip64Element != null)
{
throw new FileFormatException(SR.Get("CorruptedData"));
}
field._zip64Element = element3;
}
else if (element2 != null)
{
if (field._paddingElement != null)
{
throw new FileFormatException(SR.Get("CorruptedData"));
}
field._paddingElement = element2;
}
else
{
if (field._extraFieldElements == null)
{
field._extraFieldElements = new ArrayList(3);
}
field._extraFieldElements.Add(element);
}
expectedExtraFieldSize = (ushort)(expectedExtraFieldSize - element.Size);
}
if (expectedExtraFieldSize != 0)
{
throw new FileFormatException(SR.Get("CorruptedData"));
}
if (field._zip64Element == null)
{
field._zip64Element = ZipIOExtraFieldZip64Element.CreateNew();
}
return(field);
}
internal static ZipIOExtraField CreateNew(bool createPadding)
{
ZipIOExtraField field = new ZipIOExtraField();
field._zip64Element = ZipIOExtraFieldZip64Element.CreateNew();
if (createPadding)
{
field._paddingElement = ZipIOExtraFieldPaddingElement.CreateNew();
}
return(field);
}
internal static ZipIOExtraFieldElement Parse(BinaryReader reader, ZipIOZip64ExtraFieldUsage zip64extraFieldUsage)
{
ZipIOExtraFieldElement element;
ushort id = reader.ReadUInt16();
ushort size = reader.ReadUInt16();
if (id == ZipIOExtraFieldZip64Element.ConstantFieldId)
{
element = new ZipIOExtraFieldZip64Element();
((ZipIOExtraFieldZip64Element)element).Zip64ExtraFieldUsage = zip64extraFieldUsage;
}
else if (id == ZipIOExtraFieldPaddingElement.ConstantFieldId)
{
if (size < ZipIOExtraFieldPaddingElement.MinimumFieldDataSize)
{
element = new ZipIOExtraFieldElement(id);
}
else
{
byte[] sniffiedBytes = reader.ReadBytes(ZipIOExtraFieldPaddingElement.SignatureSize);
if (ZipIOExtraFieldPaddingElement.MatchesPaddingSignature(sniffiedBytes))
{
element = new ZipIOExtraFieldPaddingElement();
}
else
{
element = new ZipIOExtraFieldElement(id, sniffiedBytes);
}
}
}
else
{
element = new ZipIOExtraFieldElement(id);
}
element.ParseDataField(reader, size);
return(element);
}