protected ByteVector FieldData(ByteVector frameData)
{
if (frameData != null)
{
uint headerSize = Id3v2FrameHeader.Size(header.Version);
uint frameDataOffset = headerSize;
uint frameDataLength = Size;
if (header.Compression || header.DataLengthIndicator)
{
frameDataLength = frameData.Mid((int)headerSize, 4).ToUInt();
frameDataLength += 4;
}
// FIXME: Impliment compression and encrpytion.
/*
#if HAVE_ZLIB
* if(d->header->compression()) {
* ByteVector data(frameDataLength);
* uLongf uLongTmp = frameDataLength;
* ::uncompress((Bytef *) data.data(),
* (uLongf *) &uLongTmp,
* (Bytef *) frameData.data() + frameDataOffset,
* size());
* return data;
* }
* else
#endif
*/
return(frameData.Mid((int)frameDataOffset, (int)frameDataLength));
}
else
{
throw new ArgumentNullException("frameData");
}
}
protected void Parse(ByteVector data)
{
if (data != null)
{
try
{
int frameDataPosition = 0;
int frameDataLength = data.Count;
// check for extended header
if (header.ExtendedHeader)
{
if (ExtendedHeader == null)
{
extendedHeader = new Id3v2ExtendedHeader();
}
ExtendedHeader.SetData(data);
if (ExtendedHeader.Size <= data.Count)
{
frameDataPosition += (int)ExtendedHeader.Size;
frameDataLength -= (int)ExtendedHeader.Size;
}
}
// check for footer -- we don'type actually need to parse it, as it *must*
// contain the same data as the header, but we do need to account for its
// size.
if (header.FooterPresent && Id3v2Footer.Size <= frameDataLength)
{
frameDataLength -= (int)Id3v2Footer.Size;
}
// parse frames
// Make sure that there is at least enough room in the remaining frame data for
// a frame header.
while (frameDataPosition < frameDataLength - Id3v2FrameHeader.Size(header.MajorVersion))
{
// If the next data is position is 0, assume that we've hit the padding
// portion of the frame data.
if (data[frameDataPosition] == 0)
{
if (header.FooterPresent)
{
TagLibDebugger.Debug("Padding *and* a footer found. This is not allowed by the spec.");
}
return;
}
Id3v2Frame frame = Id3v2FrameFactory.CreateFrame(data.Mid(frameDataPosition), header.MajorVersion);
if (frame == null)
{
return;
}
// Checks to make sure that frame parsed correctly.
if (frame.Size < 0)
{
return;
}
frameDataPosition += (int)(frame.Size + Id3v2FrameHeader.Size(header.MajorVersion));
// Only add frames with content so we don'type send out just we got in.
if (frame.Size > 0)
{
AddFrame(frame);
}
}
}
catch (Exception ex)
{
throw new ApplicationException("There was an error parsing this ID3 tag", ex);
}
}
else
{
throw new ArgumentNullException("data");
}
}