godot/modules/mono/glue/GodotSharp/GodotSharp/Core/DelegateUtils.cs
Ignacio Roldán Etcheverry 50b603c7dc C#: Begin move to .NET Core
We're targeting .NET 5 for now to make development easier while
.NET 6 is not yet released.

TEMPORARY REGRESSIONS
---------------------

Assembly unloading is not implemented yet. As such, many Godot
resources are leaked at exit. This will be re-implemented later
together with assembly hot-reloading.
2021-09-22 08:27:12 +02:00

467 lines
16 KiB
C#

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using Godot.NativeInterop;
namespace Godot
{
internal static class DelegateUtils
{
[UnmanagedCallersOnly]
internal static godot_bool DelegateEquals(IntPtr delegateGCHandleA, IntPtr delegateGCHandleB)
{
try
{
var @delegateA = (Delegate)GCHandle.FromIntPtr(delegateGCHandleA).Target;
var @delegateB = (Delegate)GCHandle.FromIntPtr(delegateGCHandleB).Target;
return (@delegateA == @delegateB).ToGodotBool();
}
catch (Exception e)
{
ExceptionUtils.DebugUnhandledException(e);
return false.ToGodotBool();
}
}
[UnmanagedCallersOnly]
internal static unsafe void InvokeWithVariantArgs(IntPtr delegateGCHandle, godot_variant** args, uint argc,
godot_variant* outRet)
{
try
{
// TODO: Optimize
var @delegate = (Delegate)GCHandle.FromIntPtr(delegateGCHandle).Target;
var managedArgs = new object[argc];
var parameterInfos = @delegate!.Method.GetParameters();
var paramsLength = parameterInfos.Length;
if (argc != paramsLength)
{
throw new InvalidOperationException(
$"The delegate expects {paramsLength} arguments, but received {argc}.");
}
for (uint i = 0; i < argc; i++)
{
managedArgs[i] = Marshaling.variant_to_mono_object_of_type(
args[i], parameterInfos[i].ParameterType);
}
object invokeRet = @delegate.DynamicInvoke(managedArgs);
*outRet = Marshaling.mono_object_to_variant(invokeRet);
}
catch (Exception e)
{
ExceptionUtils.DebugPrintUnhandledException(e);
*outRet = default;
}
}
// TODO: Check if we should be using BindingFlags.DeclaredOnly (would give better reflection performance).
private enum TargetKind : uint
{
Static,
GodotObject,
CompilerGenerated
}
internal static bool TrySerializeDelegateWithGCHandle(IntPtr delegateGCHandle, Collections.Array serializedData)
=> TrySerializeDelegate((Delegate)GCHandle.FromIntPtr(delegateGCHandle).Target, serializedData);
private static bool TrySerializeDelegate(Delegate @delegate, Collections.Array serializedData)
{
if (@delegate is MulticastDelegate multicastDelegate)
{
bool someDelegatesSerialized = false;
Delegate[] invocationList = multicastDelegate.GetInvocationList();
if (invocationList.Length > 1)
{
var multiCastData = new Collections.Array();
foreach (Delegate oneDelegate in invocationList)
someDelegatesSerialized |= TrySerializeDelegate(oneDelegate, multiCastData);
if (!someDelegatesSerialized)
return false;
serializedData.Add(multiCastData);
return true;
}
}
if (TrySerializeSingleDelegate(@delegate, out byte[] buffer))
{
serializedData.Add(buffer);
return true;
}
return false;
}
private static bool TrySerializeSingleDelegate(Delegate @delegate, out byte[] buffer)
{
buffer = null;
object target = @delegate.Target;
switch (target)
{
case null:
{
using (var stream = new MemoryStream())
using (var writer = new BinaryWriter(stream))
{
writer.Write((ulong)TargetKind.Static);
SerializeType(writer, @delegate.GetType());
if (!TrySerializeMethodInfo(writer, @delegate.Method))
return false;
buffer = stream.ToArray();
return true;
}
}
// ReSharper disable once RedundantNameQualifier
case Godot.Object godotObject:
{
using (var stream = new MemoryStream())
using (var writer = new BinaryWriter(stream))
{
writer.Write((ulong)TargetKind.GodotObject);
// ReSharper disable once RedundantCast
writer.Write((ulong)godotObject.GetInstanceId());
SerializeType(writer, @delegate.GetType());
if (!TrySerializeMethodInfo(writer, @delegate.Method))
return false;
buffer = stream.ToArray();
return true;
}
}
default:
{
Type targetType = target.GetType();
if (targetType.IsDefined(typeof(CompilerGeneratedAttribute), true))
{
// Compiler generated. Probably a closure. Try to serialize it.
using (var stream = new MemoryStream())
using (var writer = new BinaryWriter(stream))
{
writer.Write((ulong)TargetKind.CompilerGenerated);
SerializeType(writer, targetType);
SerializeType(writer, @delegate.GetType());
if (!TrySerializeMethodInfo(writer, @delegate.Method))
return false;
FieldInfo[] fields = targetType.GetFields(BindingFlags.Instance | BindingFlags.Public);
writer.Write(fields.Length);
foreach (FieldInfo field in fields)
{
Type fieldType = field.GetType();
Variant.Type variantType = GD.TypeToVariantType(fieldType);
if (variantType == Variant.Type.Nil)
return false;
writer.Write(field.Name);
byte[] valueBuffer = GD.Var2Bytes(field.GetValue(target));
writer.Write(valueBuffer.Length);
writer.Write(valueBuffer);
}
buffer = stream.ToArray();
return true;
}
}
return false;
}
}
}
private static bool TrySerializeMethodInfo(BinaryWriter writer, MethodInfo methodInfo)
{
if (methodInfo == null)
return false;
SerializeType(writer, methodInfo.DeclaringType);
writer.Write(methodInfo.Name);
int flags = 0;
if (methodInfo.IsPublic)
flags |= (int)BindingFlags.Public;
else
flags |= (int)BindingFlags.NonPublic;
if (methodInfo.IsStatic)
flags |= (int)BindingFlags.Static;
else
flags |= (int)BindingFlags.Instance;
writer.Write(flags);
Type returnType = methodInfo.ReturnType;
bool hasReturn = methodInfo.ReturnType != typeof(void);
writer.Write(hasReturn);
if (hasReturn)
SerializeType(writer, returnType);
ParameterInfo[] parameters = methodInfo.GetParameters();
writer.Write(parameters.Length);
if (parameters.Length > 0)
{
for (int i = 0; i < parameters.Length; i++)
SerializeType(writer, parameters[i].ParameterType);
}
return true;
}
private static void SerializeType(BinaryWriter writer, Type type)
{
if (type == null)
{
int genericArgumentsCount = -1;
writer.Write(genericArgumentsCount);
}
else if (type.IsGenericType)
{
Type genericTypeDef = type.GetGenericTypeDefinition();
Type[] genericArgs = type.GetGenericArguments();
int genericArgumentsCount = genericArgs.Length;
writer.Write(genericArgumentsCount);
string assemblyQualifiedName = genericTypeDef.AssemblyQualifiedName;
Debug.Assert(assemblyQualifiedName != null);
writer.Write(assemblyQualifiedName);
for (int i = 0; i < genericArgs.Length; i++)
SerializeType(writer, genericArgs[i]);
}
else
{
int genericArgumentsCount = 0;
writer.Write(genericArgumentsCount);
string assemblyQualifiedName = type.AssemblyQualifiedName;
Debug.Assert(assemblyQualifiedName != null);
writer.Write(assemblyQualifiedName);
}
}
private static bool TryDeserializeDelegateWithGCHandle(Collections.Array serializedData,
out IntPtr delegateGCHandle)
{
bool res = TryDeserializeDelegate(serializedData, out Delegate @delegate);
delegateGCHandle = GCHandle.ToIntPtr(GCHandle.Alloc(@delegate));
return res;
}
private static bool TryDeserializeDelegate(Collections.Array serializedData, out Delegate @delegate)
{
if (serializedData.Count == 1)
{
object elem = serializedData[0];
if (elem is Collections.Array multiCastData)
return TryDeserializeDelegate(multiCastData, out @delegate);
return TryDeserializeSingleDelegate((byte[])elem, out @delegate);
}
@delegate = null;
var delegates = new List<Delegate>(serializedData.Count);
foreach (object elem in serializedData)
{
if (elem is Collections.Array multiCastData)
{
if (TryDeserializeDelegate(multiCastData, out Delegate oneDelegate))
delegates.Add(oneDelegate);
}
else
{
if (TryDeserializeSingleDelegate((byte[])elem, out Delegate oneDelegate))
delegates.Add(oneDelegate);
}
}
if (delegates.Count <= 0)
return false;
@delegate = delegates.Count == 1 ? delegates[0] : Delegate.Combine(delegates.ToArray());
return true;
}
private static bool TryDeserializeSingleDelegate(byte[] buffer, out Delegate @delegate)
{
@delegate = null;
using (var stream = new MemoryStream(buffer, writable: false))
using (var reader = new BinaryReader(stream))
{
var targetKind = (TargetKind)reader.ReadUInt64();
switch (targetKind)
{
case TargetKind.Static:
{
Type delegateType = DeserializeType(reader);
if (delegateType == null)
return false;
if (!TryDeserializeMethodInfo(reader, out MethodInfo methodInfo))
return false;
@delegate = Delegate.CreateDelegate(delegateType, null, methodInfo);
return true;
}
case TargetKind.GodotObject:
{
ulong objectId = reader.ReadUInt64();
// ReSharper disable once RedundantNameQualifier
Godot.Object godotObject = GD.InstanceFromId(objectId);
if (godotObject == null)
return false;
Type delegateType = DeserializeType(reader);
if (delegateType == null)
return false;
if (!TryDeserializeMethodInfo(reader, out MethodInfo methodInfo))
return false;
@delegate = Delegate.CreateDelegate(delegateType, godotObject, methodInfo);
return true;
}
case TargetKind.CompilerGenerated:
{
Type targetType = DeserializeType(reader);
if (targetType == null)
return false;
Type delegateType = DeserializeType(reader);
if (delegateType == null)
return false;
if (!TryDeserializeMethodInfo(reader, out MethodInfo methodInfo))
return false;
int fieldCount = reader.ReadInt32();
object recreatedTarget = Activator.CreateInstance(targetType);
for (int i = 0; i < fieldCount; i++)
{
string name = reader.ReadString();
int valueBufferLength = reader.ReadInt32();
byte[] valueBuffer = reader.ReadBytes(valueBufferLength);
FieldInfo fieldInfo =
targetType.GetField(name, BindingFlags.Instance | BindingFlags.Public);
fieldInfo?.SetValue(recreatedTarget, GD.Bytes2Var(valueBuffer));
}
@delegate = Delegate.CreateDelegate(delegateType, recreatedTarget, methodInfo);
return true;
}
default:
return false;
}
}
}
private static bool TryDeserializeMethodInfo(BinaryReader reader, out MethodInfo methodInfo)
{
methodInfo = null;
Type declaringType = DeserializeType(reader);
string methodName = reader.ReadString();
int flags = reader.ReadInt32();
bool hasReturn = reader.ReadBoolean();
Type returnType = hasReturn ? DeserializeType(reader) : typeof(void);
int parametersCount = reader.ReadInt32();
if (parametersCount > 0)
{
var parameterTypes = new Type[parametersCount];
for (int i = 0; i < parametersCount; i++)
{
Type parameterType = DeserializeType(reader);
if (parameterType == null)
return false;
parameterTypes[i] = parameterType;
}
methodInfo = declaringType.GetMethod(methodName, (BindingFlags)flags, null, parameterTypes, null);
return methodInfo != null && methodInfo.ReturnType == returnType;
}
methodInfo = declaringType.GetMethod(methodName, (BindingFlags)flags);
return methodInfo != null && methodInfo.ReturnType == returnType;
}
private static Type DeserializeType(BinaryReader reader)
{
int genericArgumentsCount = reader.ReadInt32();
if (genericArgumentsCount == -1)
return null;
string assemblyQualifiedName = reader.ReadString();
var type = Type.GetType(assemblyQualifiedName);
if (type == null)
return null; // Type not found
if (genericArgumentsCount != 0)
{
var genericArgumentTypes = new Type[genericArgumentsCount];
for (int i = 0; i < genericArgumentsCount; i++)
{
Type genericArgumentType = DeserializeType(reader);
if (genericArgumentType == null)
return null;
genericArgumentTypes[i] = genericArgumentType;
}
type = type.MakeGenericType(genericArgumentTypes);
}
return type;
}
}
}