private static object ReadValue(ModuleDefinition parentModule, TypeSignature valueType, IBinaryStreamReader reader)
{
switch (valueType.ElementType)
{
case ElementType.Boolean:
return(reader.ReadByte() == 1);
case ElementType.Char:
return((char)reader.ReadUInt16());
case ElementType.R4:
return(reader.ReadSingle());
case ElementType.R8:
return(reader.ReadDouble());
case ElementType.I1:
return(reader.ReadSByte());
case ElementType.I2:
return(reader.ReadInt16());
case ElementType.I4:
return(reader.ReadInt32());
case ElementType.I8:
return(reader.ReadInt64());
case ElementType.U1:
return(reader.ReadByte());
case ElementType.U2:
return(reader.ReadUInt16());
case ElementType.U4:
return(reader.ReadUInt32());
case ElementType.U8:
return(reader.ReadUInt64());
case ElementType.String:
return(reader.ReadSerString());
case ElementType.Object:
return(ReadValue(parentModule, TypeSignature.ReadFieldOrPropType(parentModule, reader), reader));
case ElementType.Class:
case ElementType.Enum:
case ElementType.ValueType:
var enumTypeDef = parentModule.MetadataResolver.ResolveType(valueType);
if (enumTypeDef != null && enumTypeDef.IsEnum)
{
return(ReadValue(parentModule, enumTypeDef.GetEnumUnderlyingType(), reader));
}
break;
}
if (valueType.IsTypeOf("System", "Type"))
{
return(TypeNameParser.Parse(parentModule, reader.ReadSerString()));
}
throw new NotSupportedException($"Unsupported element type {valueType.ElementType}.");
}
private void WriteElement(TypeSignature argumentType, object element)
{
var writer = _context.Writer;
if (argumentType.IsTypeOf("System", "Type"))
{
writer.WriteSerString(TypeNameBuilder.GetAssemblyQualifiedName((TypeSignature)element));
return;
}
switch (argumentType.ElementType)
{
case ElementType.Boolean:
writer.WriteByte((byte)((bool)element ? 1 : 0));
break;
case ElementType.Char:
writer.WriteUInt16((char)element);
break;
case ElementType.I1:
writer.WriteSByte((sbyte)element);
break;
case ElementType.U1:
writer.WriteByte((byte)element);
break;
case ElementType.I2:
writer.WriteInt16((short)element);
break;
case ElementType.U2:
writer.WriteUInt16((ushort)element);
break;
case ElementType.I4:
writer.WriteInt32((int)element);
break;
case ElementType.U4:
writer.WriteUInt32((uint)element);
break;
case ElementType.I8:
writer.WriteInt64((long)element);
break;
case ElementType.U8:
writer.WriteUInt64((ulong)element);
break;
case ElementType.R4:
writer.WriteSingle((float)element);
break;
case ElementType.R8:
writer.WriteDouble((double)element);
break;
case ElementType.String:
writer.WriteSerString(element as string);
break;
case ElementType.Object:
TypeSignature innerTypeSig;
object value;
if (element is null)
{
// Most efficient way to store "null" is writing null as a string (two bytes).
innerTypeSig = argumentType.Module.CorLibTypeFactory.String;
value = null;
}
else if (element is BoxedArgument boxedArgument)
{
// Write the boxed argument.
innerTypeSig = boxedArgument.Type;
value = boxedArgument.Value;
}
else
{
_context.DiagnosticBag.RegisterException(new NotSupportedException(
$"Object elements in a custom attribute signature should be either 'null' or an instance of {nameof(BoxedArgument)}."));
// Write null as a recovery.
innerTypeSig = argumentType.Module.CorLibTypeFactory.String;
value = null;
}
TypeSignature.WriteFieldOrPropType(writer, innerTypeSig);
WriteElement(innerTypeSig, value);
break;
case ElementType.SzArray:
WriteArrayElement(
(SzArrayTypeSignature)argumentType,
element as IList <object> ?? new object[0],
element == null);
break;
case ElementType.Class:
case ElementType.Enum:
case ElementType.ValueType:
WriteEnumValue(argumentType, element);
break;
default:
UnsupportedArgumentType(argumentType);
break;
}
}
private void WriteValue(IBinaryStreamWriter writer, TypeSignature argumentType, ITypeCodedIndexProvider provider, object value)
{
if (argumentType.IsTypeOf("System", "Type"))
{
writer.WriteSerString(TypeNameBuilder.GetAssemblyQualifiedName((TypeSignature)value));
return;
}
switch (argumentType.ElementType)
{
case ElementType.Boolean:
writer.WriteByte((byte)((bool)value ? 1 : 0));
break;
case ElementType.Char:
writer.WriteUInt16((char)value);
break;
case ElementType.I1:
writer.WriteSByte((sbyte)value);
break;
case ElementType.U1:
writer.WriteByte((byte)value);
break;
case ElementType.I2:
writer.WriteInt16((short)value);
break;
case ElementType.U2:
writer.WriteUInt16((ushort)value);
break;
case ElementType.I4:
writer.WriteInt32((int)value);
break;
case ElementType.U4:
writer.WriteUInt32((uint)value);
break;
case ElementType.I8:
writer.WriteInt64((long)value);
break;
case ElementType.U8:
writer.WriteUInt64((ulong)value);
break;
case ElementType.R4:
writer.WriteSingle((float)value);
break;
case ElementType.R8:
writer.WriteDouble((double)value);
break;
case ElementType.String:
writer.WriteSerString(value as string);
break;
case ElementType.Object:
var valueType = value.GetType();
var innerTypeSig = argumentType.Module.CorLibTypeFactory.FromName(valueType.Namespace, valueType.Name);
TypeSignature.WriteFieldOrPropType(writer, innerTypeSig);
WriteValue(writer, innerTypeSig, provider, value);
break;
case ElementType.Class:
case ElementType.Enum:
case ElementType.ValueType:
var enumTypeDef = argumentType.Resolve();
if (enumTypeDef != null && enumTypeDef.IsEnum)
{
WriteValue(writer, enumTypeDef.GetEnumUnderlyingType(), provider, Value);
}
else
{
throw new NotImplementedException();
}
break;
default:
throw new ArgumentOutOfRangeException();
}
}
public void ReadValue(TypeSignature valueType)
{
if (valueType.IsTypeOf("System", "Type"))
{
Elements.Add(TypeNameParser.Parse(_parentModule, _reader.ReadSerString()));
return;
}
switch (valueType.ElementType)
{
case ElementType.Boolean:
Elements.Add(_reader.ReadByte() == 1);
break;
case ElementType.Char:
Elements.Add((char)_reader.ReadUInt16());
break;
case ElementType.R4:
Elements.Add(_reader.ReadSingle());
break;
case ElementType.R8:
Elements.Add(_reader.ReadDouble());
break;
case ElementType.I1:
Elements.Add(_reader.ReadSByte());
break;
case ElementType.I2:
Elements.Add(_reader.ReadInt16());
break;
case ElementType.I4:
Elements.Add(_reader.ReadInt32());
break;
case ElementType.I8:
Elements.Add(_reader.ReadInt64());
break;
case ElementType.U1:
Elements.Add(_reader.ReadByte());
break;
case ElementType.U2:
Elements.Add(_reader.ReadUInt16());
break;
case ElementType.U4:
Elements.Add(_reader.ReadUInt32());
break;
case ElementType.U8:
Elements.Add(_reader.ReadUInt64());
break;
case ElementType.String:
Elements.Add(_reader.ReadSerString());
break;
case ElementType.Object:
var reader = new CustomAttributeArgumentReader(_parentModule, _reader);
var type = TypeSignature.ReadFieldOrPropType(_parentModule, _reader);
reader.ReadValue(type);
Elements.Add(new BoxedArgument(type, type.ElementType == ElementType.SzArray
? reader.Elements.ToArray()
: reader.Elements[0]));
break;
case ElementType.SzArray:
var arrayElementType = ((SzArrayTypeSignature)valueType).BaseType;
uint elementCount = _reader.CanRead(sizeof(uint)) ? _reader.ReadUInt32() : uint.MaxValue;
IsNullArray = elementCount == uint.MaxValue;
if (!IsNullArray)
{
for (uint i = 0; i < elementCount; i++)
{
ReadValue(arrayElementType);
}
}
break;
case ElementType.Class:
case ElementType.Enum:
case ElementType.ValueType:
// Value is an enum, resolve it and get underlying type.
// If that fails, most enums are int32s, assume that is the case in an attempt to recover.
var enumTypeDef = _parentModule.MetadataResolver.ResolveType(valueType);
TypeSignature underlyingType;
if (enumTypeDef is null)
{
underlyingType = _parentModule.CorLibTypeFactory.Int32;
}
else if (enumTypeDef.IsEnum)
{
underlyingType = enumTypeDef.GetEnumUnderlyingType() ?? _parentModule.CorLibTypeFactory.Int32;
}
else
{
throw new NotSupportedException($"Type {valueType} is not an enum.");
}
ReadValue(underlyingType);
break;
default:
throw new NotSupportedException($"Unsupported element type {valueType.ElementType}.");
}
}