/// <summary>
/// Factory method parsing <see cref="BaseBandFrame"/>.
/// </summary>
/// <param name="reader"><see cref="PDUStreamReader"/> for stream from which the <see cref="BaseBandFrame"/>
/// should be parsed.</param>
/// <exception cref="NotImplementedException">If TS/GS (<see cref="TsGs"/>) is other than Generic Continuous Stream Input.</exception>
/// <exception cref="InvalidPacketFormatException">If read data does not correspond to valid format.</exception>
/// <returns>Parsed <see cref="BaseBandFrame"/> object.</returns>
public static BaseBandFrame Parse(PDUStreamReader reader)
{
var mah = ModeAdaptationHeaderL3.Parse(reader);
var bbh = BaseBandHeader.Parse(reader);
if (bbh.Matype1.TsGs != TsGs.GenericContinuous)
{
throw new NotImplementedException("Only Generic Continuous Stream Input is supported at this moment.");
}
var l7PDU = reader.PDUStreamBasedProvider.GetCurrentPDU();
var userPackets = new List <GsePacket>();
while (!reader.EndOfPDU)
{
try
{
userPackets.Add(GsePacket.Parse(reader));
}
catch (InvalidPacketFormatException)
{
// NOTE: Invalid format for GSE packet, in base band frame
}
}
return(new BaseBandFrame(mah, bbh, ImmutableList.CreateRange(userPackets), l7PDU));
}
/// <summary>
/// Add fragmented <paramref name="gsePacket"/>, which was carried in <paramref name="encapsulatingFrames"/>, to this buffer.
/// </summary>
/// <param name="gsePacket">Fragmetned GSE packet</param>
/// <param name="encapsulatingFrames">Frames which carried provided <paramref name="gsePacket"/></param>
/// <exception cref="ArgumentException">If <paramref name="gsePacket"/> is not a GSE fragment packet (<see cref="GsePacket.IsGseFragment"/>==false).</exception>
public void Add([Required] GsePacket gsePacket, [Required] IEnumerable <PmFrameBase> encapsulatingFrames)
{
if (!gsePacket.IsGseFragment)
{
throw new ArgumentException("GSE packet is not a GSE fragment packet.", nameof(gsePacket));
}
// check if gsePacket can be added to this buffer based on the sequence of types of GSE packets in this buffer
// (Start Intermediate* End)
switch (gsePacket.Type)
{
case PacketType.Padding:
case PacketType.Complete:
throw new ArgumentException($"GSE packet with type {gsePacket.Type} cannot be added to GseReassemblyBuffer.", nameof(gsePacket));
case PacketType.Start:
if (this._buffer.Any())
{
throw new ArgumentException($"GSE packet with type {gsePacket.Type} cannot be added to not empty GseReassemblyBuffer.", nameof(gsePacket));
}
break;
case PacketType.Intermediate:
case PacketType.End:
if (this._buffer.Any())
{
if (!(this._buffer.Last().Type == PacketType.Start || this._buffer.Last().Type == PacketType.Intermediate))
{
throw new ArgumentException($"GSE packet with type {gsePacket.Type} cannot be added to GseReassemblyBuffer after packet with type {this._buffer.Last().Type}.", nameof(gsePacket));
}
}
else
{
throw new ArgumentException($"GSE packet with type {gsePacket.Type} cannot be added to empty GseReassemblyBuffer.", nameof(gsePacket));
}
break;
default:
throw new ArgumentOutOfRangeException();
}
this._buffer.Add(gsePacket);
foreach (var ef in encapsulatingFrames)
{
if (!this._encapsulatingFrames.Contains(ef))
{
this._encapsulatingFrames.Add(ef);
}
}
}