protected override void ReadAmfValue(AmfContext context, AmfStreamReader reader, XmlWriter output = null)
{
//Work in a legacy context
if (context.AmfVersion == AmfVersion.Amf0)
{
base.ReadAmfValue(context, reader, output);
return;
}
Amf3TypeMarker dataType;
try
{
//Read a type marker byte
dataType = (Amf3TypeMarker)reader.ReadByte();
}
catch (Exception e)
{
#if DEBUG
Debug.WriteLine(string.Format(Errors.Amf3Decoder_ReadValue_InvalidMarker, reader.BaseStream.Position));
#endif
throw new FormatException(string.Format(Errors.Amf3Decoder_ReadValue_TypeMarkerNotFound, reader.BaseStream.Position), e);
}
ReadValue(context, reader, dataType, output);
#if DEBUG
Debug.WriteLine(string.Format(Errors.Amf3Decoder_ReadValue_End, dataType, reader.BaseStream.Position));
#endif
}
protected override void ReadAmfValue(AmfContext context, AmfStreamReader reader, XmlWriter output = null)
{
if (context.AmfVersion != AmfVersion.Amf0)
throw new InvalidOperationException(string.Format(Errors.Amf0Decoder_ReadAmfValue_AmfVersionNotSupported, context.AmfVersion));
Amf0TypeMarker dataType;
try
{
//Read a type marker byte
dataType = (Amf0TypeMarker)reader.ReadByte();
}
catch (Exception e)
{
throw new FormatException(Errors.Amf0Decoder_ReadAmfValue_TypeMarkerMissing, e);
}
//Special case
if(dataType == Amf0TypeMarker.AvmPlusObject)
{
var newContext = new AmfContext(AmfVersion.Amf3);
ReadAmfValue(newContext, reader, output);
return;
}
ReadValue(context, reader, dataType, output);
}
/// <summary>
/// Read a 29-bit unsigned integer.
/// </summary>
/// <remarks>
/// Up to 4 bytes are required to hold the value however the high bit
/// of the first 3 bytes are used as flags to determine
/// whether the next byte is part of the integer.
/// <c>
/// 0x00000000 - 0x0000007F : 0xxxxxxx
/// 0x00000080 - 0x00003FFF : 1xxxxxxx 0xxxxxxx
/// 0x00004000 - 0x001FFFFF : 1xxxxxxx 1xxxxxxx 0xxxxxxx
/// 0x00200000 - 0x3FFFFFFF : 1xxxxxxx 1xxxxxxx 1xxxxxxx xxxxxxxx
/// 0x40000000 - 0xFFFFFFFF : throw range exception
/// </c>
/// </remarks>
private static int ReadUint29(AmfStreamReader reader)
{
const byte mask = 0x7F; //0111 1111
var octet = reader.ReadByte() & 0xFF;
//0xxxxxxx
if (octet < 128) return octet;
var result = (octet & mask) << 7;
octet = reader.ReadByte() & 0xFF;
//1xxxxxxx 0xxxxxxx
if (octet < 128) return (result | octet);
result = (result | (octet & mask)) << 7;
octet = reader.ReadByte() & 0xFF;
//1xxxxxxx 1xxxxxxx 0xxxxxxx
if (octet < 128) return (result | octet);
result = (result | (octet & mask)) << 8;
octet = reader.ReadByte() & 0xFF;
//1xxxxxxx 1xxxxxxx 1xxxxxxx xxxxxxxx
return (result | octet);
}
/// <summary>
/// Read object properties map.
/// </summary>
/// <remarks>
/// Type declaration:
/// <c>object-property = (UTF-8 value-type) | (UTF-8-empty object-end-marker)</c>
/// </remarks>
/// <exception cref="SerializationException"></exception>
private IList<string> ReadPropertiesMap(AmfContext context, AmfStreamReader reader, XmlWriter output = null)
{
try
{
var result = new List<string>();
var property = ReadString(reader); //Read first property's name
//An empty property name indicates that object's declaration ends here
while (property != string.Empty)
{
result.Add(property);
ReadAmfValue(context, reader, output);
property = ReadString(reader);
}
//Last byte is always an "ObjectEnd" marker
var marker = (Amf0TypeMarker)reader.ReadByte();
//Something goes wrong
if (marker != Amf0TypeMarker.ObjectEnd)
throw new FormatException(Errors.Amf0Decoder_ReadPropertiesMap_UnexpectedObjectEnd);
return result;
}
catch (Exception e)
{
throw new SerializationException(Errors.Amf0Decoder_ReadPropertiesMap_UnableToDeserialize, e);
}
}
