private ImmutableArray <CustomAttributeNamedArgument <TType> > DecodeNamedArguments(ref BlobReader valueReader)
{
int count = valueReader.ReadUInt16();
if (count == 0)
{
return(ImmutableArray <CustomAttributeNamedArgument <TType> > .Empty);
}
var arguments = ImmutableArray.CreateBuilder <CustomAttributeNamedArgument <TType> >(count);
for (int i = 0; i < count; i++)
{
CustomAttributeNamedArgumentKind kind = (CustomAttributeNamedArgumentKind)valueReader.ReadSerializationTypeCode();
if (kind != CustomAttributeNamedArgumentKind.Field && kind != CustomAttributeNamedArgumentKind.Property)
{
throw new BadImageFormatException();
}
ArgumentTypeInfo info = DecodeNamedArgumentType(ref valueReader);
string? name = valueReader.ReadSerializedString();
CustomAttributeTypedArgument <TType> argument = DecodeArgument(ref valueReader, info);
arguments.Add(new CustomAttributeNamedArgument <TType>(name, kind, argument.Type, argument.Value));
}
return(arguments.MoveToImmutable());
}
private ImmutableArray <CustomAttributeTypedArgument <TType> >?DecodeArrayArgument(ref BlobReader blobReader, ArgumentTypeInfo info)
{
int count = blobReader.ReadInt32();
if (count == -1)
{
return(null);
}
if (count == 0)
{
return(ImmutableArray <CustomAttributeTypedArgument <TType> > .Empty);
}
if (count < 0)
{
throw new BadImageFormatException();
}
var elementInfo = new ArgumentTypeInfo
{
Type = info.ElementType,
TypeCode = info.ElementTypeCode,
};
var array = ImmutableArray.CreateBuilder <CustomAttributeTypedArgument <TType> >(count);
for (int i = 0; i < count; i++)
{
array.Add(DecodeArgument(ref blobReader, elementInfo));
}
return(array.MoveToImmutable());
}
private ArgumentTypeInfo DecodeNamedArgumentType(ref BlobReader valueReader, bool isElementType = false)
{
var info = new ArgumentTypeInfo
{
TypeCode = valueReader.ReadSerializationTypeCode(),
};
switch (info.TypeCode)
{
case SerializationTypeCode.Boolean:
case SerializationTypeCode.Byte:
case SerializationTypeCode.Char:
case SerializationTypeCode.Double:
case SerializationTypeCode.Int16:
case SerializationTypeCode.Int32:
case SerializationTypeCode.Int64:
case SerializationTypeCode.SByte:
case SerializationTypeCode.Single:
case SerializationTypeCode.String:
case SerializationTypeCode.UInt16:
case SerializationTypeCode.UInt32:
case SerializationTypeCode.UInt64:
info.Type = _provider.GetPrimitiveType((PrimitiveTypeCode)info.TypeCode);
break;
case SerializationTypeCode.Type:
info.Type = _provider.GetSystemType();
break;
case SerializationTypeCode.TaggedObject:
info.Type = _provider.GetPrimitiveType(PrimitiveTypeCode.Object);
break;
case SerializationTypeCode.SZArray:
if (isElementType)
{
// jagged arrays are not allowed.
throw new BadImageFormatException();
}
var elementInfo = DecodeNamedArgumentType(ref valueReader, isElementType: true);
info.ElementType = elementInfo.Type;
info.ElementTypeCode = elementInfo.TypeCode;
info.Type = _provider.GetSZArrayType(info.ElementType);
break;
case SerializationTypeCode.Enum:
string?typeName = valueReader.ReadSerializedString();
info.Type = _provider.GetTypeFromSerializedName(typeName !);
info.TypeCode = (SerializationTypeCode)_provider.GetUnderlyingEnumType(info.Type);
break;
default:
throw new BadImageFormatException();
}
return(info);
}
// Decodes a fixed argument type of a custom attribute from its constructor signature.
//
// Note that we do not decode the full constructor signature using DecodeMethodSignature
// but instead decode one parameter at a time as we read the value blob. This is both
// better perf-wise, but even more important is that we can't actually reason about
// a method signature with opaque TType values without adding some unnecessary chatter
// with the provider.
private ArgumentTypeInfo DecodeFixedArgumentType(ref BlobReader signatureReader, bool isElementType = false)
{
SignatureTypeCode signatureTypeCode = signatureReader.ReadSignatureTypeCode();
var info = new ArgumentTypeInfo
{
TypeCode = (SerializationTypeCode)signatureTypeCode,
};
switch (signatureTypeCode)
{
case SignatureTypeCode.Boolean:
case SignatureTypeCode.Byte:
case SignatureTypeCode.Char:
case SignatureTypeCode.Double:
case SignatureTypeCode.Int16:
case SignatureTypeCode.Int32:
case SignatureTypeCode.Int64:
case SignatureTypeCode.SByte:
case SignatureTypeCode.Single:
case SignatureTypeCode.String:
case SignatureTypeCode.UInt16:
case SignatureTypeCode.UInt32:
case SignatureTypeCode.UInt64:
info.Type = _provider.GetPrimitiveType((PrimitiveTypeCode)signatureTypeCode);
break;
case SignatureTypeCode.Object:
info.TypeCode = SerializationTypeCode.TaggedObject;
info.Type = _provider.GetPrimitiveType(PrimitiveTypeCode.Object);
break;
case SignatureTypeCode.TypeHandle:
// Parameter is type def or ref and is only allowed to be System.Type or Enum.
EntityHandle handle = signatureReader.ReadTypeHandle();
info.Type = GetTypeFromHandle(handle);
info.TypeCode = _provider.IsSystemType(info.Type) ? SerializationTypeCode.Type : (SerializationTypeCode)_provider.GetUnderlyingEnumType(info.Type);
break;
case SignatureTypeCode.SZArray:
if (isElementType)
{
// jagged arrays are not allowed.
throw new BadImageFormatException();
}
var elementInfo = DecodeFixedArgumentType(ref signatureReader, isElementType: true);
info.ElementType = elementInfo.Type;
info.ElementTypeCode = elementInfo.TypeCode;
info.Type = _provider.GetSZArrayType(info.ElementType);
break;
default:
throw new BadImageFormatException();
}
return(info);
}
private ImmutableArray <CustomAttributeTypedArgument <TType> > DecodeFixedArguments(ref BlobReader signatureReader, ref BlobReader valueReader, int count)
{
if (count == 0)
{
return(ImmutableArray <CustomAttributeTypedArgument <TType> > .Empty);
}
var arguments = ImmutableArray.CreateBuilder <CustomAttributeTypedArgument <TType> >(count);
for (int i = 0; i < count; i++)
{
ArgumentTypeInfo info = DecodeFixedArgumentType(ref signatureReader);
arguments.Add(DecodeArgument(ref valueReader, info));
}
return(arguments.MoveToImmutable());
}
private CustomAttributeTypedArgument <TType> DecodeArgument(ref BlobReader valueReader, ArgumentTypeInfo info)
{
if (info.TypeCode == SerializationTypeCode.TaggedObject)
{
info = DecodeNamedArgumentType(ref valueReader);
}
// PERF_TODO: https://github.com/dotnet/corefx/issues/6533
// Cache /reuse common arguments to avoid boxing (small integers, true, false).
object?value;
switch (info.TypeCode)
{
case SerializationTypeCode.Boolean:
value = valueReader.ReadBoolean();
break;
case SerializationTypeCode.Byte:
value = valueReader.ReadByte();
break;
case SerializationTypeCode.Char:
value = valueReader.ReadChar();
break;
case SerializationTypeCode.Double:
value = valueReader.ReadDouble();
break;
case SerializationTypeCode.Int16:
value = valueReader.ReadInt16();
break;
case SerializationTypeCode.Int32:
value = valueReader.ReadInt32();
break;
case SerializationTypeCode.Int64:
value = valueReader.ReadInt64();
break;
case SerializationTypeCode.SByte:
value = valueReader.ReadSByte();
break;
case SerializationTypeCode.Single:
value = valueReader.ReadSingle();
break;
case SerializationTypeCode.UInt16:
value = valueReader.ReadUInt16();
break;
case SerializationTypeCode.UInt32:
value = valueReader.ReadUInt32();
break;
case SerializationTypeCode.UInt64:
value = valueReader.ReadUInt64();
break;
case SerializationTypeCode.String:
value = valueReader.ReadSerializedString();
break;
case SerializationTypeCode.Type:
string?typeName = valueReader.ReadSerializedString();
value = _provider.GetTypeFromSerializedName(typeName !);
break;
case SerializationTypeCode.SZArray:
value = DecodeArrayArgument(ref valueReader, info);
break;
default:
throw new BadImageFormatException();
}
return(new CustomAttributeTypedArgument <TType>(info.Type, value));
}
