internal static TypeReference GetTypeReference(ModuleDefinition module, object param)
{
return(param switch
{
Type paramType => module.ImportReference(paramType),
InlineSignature paramSig => paramSig.ToFunctionPointer(module),
ModifierType paramMod => paramMod.ToTypeReference(module),
_ => throw new NotSupportedException($"Unsupported inline signature parameter type: {param} ({param?.GetType().FullDescription()})"),
});
// Based on https://github.com/MonoMod/MonoMod.Common/blob/fb7fed148af165905ee0f2db1bb4c78a0137fb89/Utils/ReflectionHelper.ParseCallSite.cs
// ... which is based on https://github.com/jbevain/cecil/blob/96026325ee1cb6627a3e4a32b924ab2905f02553/Mono.Cecil/AssemblyReader.cs#L3448
internal static InlineSignature ImportCallSite(Module moduleFrom, byte[] data)
{
var callsite = new InlineSignature();
// Based on https://github.com/jbevain/cecil/blob/96026325ee1cb6627a3e4a32b924ab2905f02553/Mono.Cecil/AssemblyReader.cs#L3448
using var stream = new MemoryStream(data, false);
using var reader = new BinaryReader(stream);
ReadMethodSignature(callsite);
return(callsite);
void ReadMethodSignature(InlineSignature method)
{
var callConv = reader.ReadByte();
if ((callConv & 0x20) != 0)
{
method.HasThis = true;
callConv = (byte)(callConv & ~0x20);
}
if ((callConv & 0x40) != 0)
{
method.ExplicitThis = true;
callConv = (byte)(callConv & ~0x40);
}
method.CallingConvention = (CallingConvention)callConv + 1;
if ((callConv & 0x10) != 0)
{
_ = ReadCompressedUInt32();
// Generic-ness shouldn't apply to CallSites.
}
var paramCount = ReadCompressedUInt32();
method.ReturnType = ReadTypeSignature();
for (var i = 0; i < paramCount; i++)
{
method.Parameters.Add(ReadTypeSignature());
}
}
uint ReadCompressedUInt32()
{
var first = reader.ReadByte();
if ((first & 0x80) == 0)
{
return(first);
}
if ((first & 0x40) == 0)
{
return(((uint)(first & ~0x80) << 8)
| reader.ReadByte());
}
return(((uint)(first & ~0xc0) << 24)
| (uint)reader.ReadByte() << 16
| (uint)reader.ReadByte() << 8
| reader.ReadByte());
}
int ReadCompressedInt32()
{
var b = reader.ReadByte();
_ = reader.BaseStream.Seek(-1, SeekOrigin.Current);
var u = (int)ReadCompressedUInt32();
var v = u >> 1;
if ((u & 1) == 0)
{
return(v);
}
switch (b & 0xc0)
{
case 0:
case 0x40:
return(v - 0x40);
case 0x80:
return(v - 0x2000);
default:
return(v - 0x10000000);
}
}
Type GetTypeDefOrRef()
{
var tokenData = ReadCompressedUInt32();
var rid = tokenData >> 2;
var token = (tokenData & 3) switch
{
0 => (uint)TokenType.TypeDef | rid,
1 => (uint)TokenType.TypeRef | rid,
2 => (uint)TokenType.TypeSpec | rid,
_ => (uint)0,
};
return(moduleFrom.ResolveType((int)token));
}
object ReadTypeSignature()
{
var etype = (MetadataType)reader.ReadByte();
switch (etype)
{
case MetadataType.ValueType:
case MetadataType.Class:
return(GetTypeDefOrRef());
case MetadataType.Pointer:
return(((Type)ReadTypeSignature()).MakePointerType());
case MetadataType.FunctionPointer:
var fptr = new InlineSignature();
ReadMethodSignature(fptr);
/* Note: Inline function pointer signatures cannot be made pointer / byref / array / ... types themselves.
* That's because InlineSignature does not extend Type, unlike Cecil, where function pointers are literal types.
* Unfortunately System.Reflection does not allow for creating function pointer types on demand.
* Maybe System.Reflection.Emit / Mono.Cecil can be used to emit those types instead?
* In the worst case, void* might be used instead of (fnptrtype)*
* -ade
*/
return(fptr);
case MetadataType.ByReference:
return(((Type)ReadTypeSignature()).MakePointerType());
// System.Reflection lacks PinnedType.
/*
* case MetadataType.Pinned:
* throw new NotSupportedException();
*/
case (MetadataType)0x1d: // SzArray
return(((Type)ReadTypeSignature()).MakeArrayType());
case MetadataType.Array:
var atype = (Type)ReadTypeSignature();
var rank = ReadCompressedUInt32();
// The following information cannot be used with System.Reflection,
// but it still needs to be skipped over.
var sizes = ReadCompressedUInt32();
for (var i = 0; i < sizes; i++)
{
_ = ReadCompressedUInt32();
}
var lowBounds = ReadCompressedUInt32();
for (var i = 0; i < lowBounds; i++)
{
_ = ReadCompressedInt32();
}
return(atype.MakeArrayType((int)rank));
case MetadataType.OptionalModifier:
return(new InlineSignature.ModifierType()
{
IsOptional = true,
Modifier = GetTypeDefOrRef(),
Type = ReadTypeSignature()
});
case MetadataType.RequiredModifier:
return(new InlineSignature.ModifierType()
{
IsOptional = false,
Modifier = GetTypeDefOrRef(),
Type = ReadTypeSignature()
});
// System.Reflection lacks SentinelType.
/*
* case MetadataType.Sentinel:
* throw new NotSupportedException();
*/
case MetadataType.Var:
case MetadataType.MVar:
case MetadataType.GenericInstance:
throw new NotSupportedException($"Unsupported generic callsite element: {etype}");
case MetadataType.Object:
return(typeof(object));
case MetadataType.Void:
return(typeof(void));
case MetadataType.TypedByReference:
return(typeof(TypedReference));
case MetadataType.IntPtr:
return(typeof(IntPtr));
case MetadataType.UIntPtr:
return(typeof(UIntPtr));
case MetadataType.Boolean:
return(typeof(bool));
case MetadataType.Char:
return(typeof(char));
case MetadataType.SByte:
return(typeof(sbyte));
case MetadataType.Byte:
return(typeof(byte));
case MetadataType.Int16:
return(typeof(short));
case MetadataType.UInt16:
return(typeof(ushort));
case MetadataType.Int32:
return(typeof(int));
case MetadataType.UInt32:
return(typeof(uint));
case MetadataType.Int64:
return(typeof(long));
case MetadataType.UInt64:
return(typeof(ulong));
case MetadataType.Single:
return(typeof(float));
case MetadataType.Double:
return(typeof(double));
case MetadataType.String:
return(typeof(string));
default:
throw new NotSupportedException($"Unsupported callsite element: {etype}");
}
}
}
