public unsafe static void Convert(BlobBuilder builder, MetadataModel metadataModel, byte[] signature, object value)
{
fixed(byte *sigPtr = signature)
{
var sigReader = new BlobReader(sigPtr, signature.Length);
// copy custom modifiers over:
byte rawTypeCode;
while (true)
{
rawTypeCode = sigReader.ReadByte();
if (rawTypeCode != (int)SignatureTypeCode.OptionalModifier && rawTypeCode != (int)SignatureTypeCode.RequiredModifier)
{
break;
}
builder.WriteByte(rawTypeCode);
builder.WriteCompressedInteger(sigReader.ReadCompressedInteger());
}
switch ((SignatureTypeCode)rawTypeCode)
{
case (SignatureTypeCode)SignatureTypeKind.Class:
case (SignatureTypeCode)SignatureTypeKind.ValueType:
int typeRefDefSpec = sigReader.ReadCompressedInteger();
if (value is decimal)
{
// GeneralConstant: VALUETYPE TypeDefOrRefOrSpecEncoded <decimal>
builder.WriteByte((byte)SignatureTypeKind.ValueType);
builder.WriteCompressedInteger(typeRefDefSpec);
builder.WriteDecimal((decimal)value);
}
else if (value is DateTime)
{
// GeneralConstant: VALUETYPE TypeDefOrRefOrSpecEncoded <date-time>
builder.WriteByte((byte)SignatureTypeKind.ValueType);
builder.WriteCompressedInteger(typeRefDefSpec);
builder.WriteDateTime((DateTime)value);
}
else if (value == null)
{
// GeneralConstant: CLASS TypeDefOrRefOrSpecEncoded
builder.WriteByte(rawTypeCode);
builder.WriteCompressedInteger(typeRefDefSpec);
}
else
{
// EnumConstant ::= EnumTypeCode EnumValue EnumType
// EnumTypeCode ::= BOOLEAN | CHAR | I1 | U1 | I2 | U2 | I4 | U4 | I8 | U8
// EnumType ::= TypeDefOrRefOrSpecEncoded
var enumTypeCode = MetadataHelpers.GetConstantTypeCode(value);
builder.WriteByte((byte)enumTypeCode);
builder.WriteConstant(value);
builder.WriteCompressedInteger(typeRefDefSpec);
}
break;
case SignatureTypeCode.Object:
// null:
Debug.Assert(value == null);
builder.WriteByte((byte)SignatureTypeCode.Object);
break;
case SignatureTypeCode.Boolean:
case SignatureTypeCode.Char:
case SignatureTypeCode.SByte:
case SignatureTypeCode.Byte:
case SignatureTypeCode.Int16:
case SignatureTypeCode.UInt16:
case SignatureTypeCode.Int32:
case SignatureTypeCode.UInt32:
case SignatureTypeCode.Int64:
case SignatureTypeCode.UInt64:
case SignatureTypeCode.Single:
case SignatureTypeCode.Double:
case SignatureTypeCode.String:
// PrimitiveConstant
builder.WriteByte(rawTypeCode);
builder.WriteConstant(value);
break;
case SignatureTypeCode.SZArray:
case SignatureTypeCode.Array:
case SignatureTypeCode.GenericTypeInstance:
Debug.Assert(value == null);
// Find an existing TypeSpec in metadata.
// If there isn't one we can't represent the constant type in the Portable PDB, use Object.
// +1/-1 for the type code we already read.
var spec = new byte[sigReader.RemainingBytes + 1];
Buffer.BlockCopy(signature, sigReader.Offset - 1, spec, 0, spec.Length);
TypeSpecificationHandle typeSpec;
if (metadataModel.TryResolveTypeSpecification(spec, out typeSpec))
{
builder.WriteCompressedInteger(CodedIndex.TypeDefOrRefOrSpec(typeSpec));
}
else
{
// TODO: warning - can't translate const type
builder.WriteByte((byte)SignatureTypeCode.Object);
}
break;
case SignatureTypeCode.GenericMethodParameter:
case SignatureTypeCode.GenericTypeParameter:
case SignatureTypeCode.FunctionPointer:
case SignatureTypeCode.Pointer:
// generic parameters, pointers are not valid types for constants:
throw new BadImageFormatException();
}
}
}