private static MethodDefinition CreateGetResourceAssemblyStreamOrNullMethod(FieldReference dictionaryField, TypeReference moduleType, MetadataHelper helper)
{
// C#:
// private static Stream GetResourceAssemblyStreamOrNull(AssemblyName assemblyName)
// {
// return EmbeddedResourceNamesByAssemblyName.TryGetValue(assemblyName.Name, out var resourceName)
// ? typeof(Module).Assembly.GetManifestResourceStream(resourceName)
// : null;
// }
var method = helper.DefineMethod(
"GetResourceAssemblyStreamOrNull",
MethodAttributes.Private | MethodAttributes.Static | MethodAttributes.HideBySig,
returnType: "class System.IO.Stream",
parameterTypes: new[] { "class System.Reflection.AssemblyName" });
var programBuilder = new ProgramBuilder(method.Body, helper);
var resourceNameVariable = programBuilder.CreateLocal("string");
var successLabel = new Label();
programBuilder.Append(
Ldsfld(dictionaryField),
Ldarg(0),
Callvirt("instance string System.Reflection.AssemblyName::get_Name()"),
Ldloca(resourceNameVariable),
Callvirt("instance bool class System.Collections.Generic.Dictionary`2<string, string>::TryGetValue(!0, !1&)"),
Brtrue_S(successLabel),
Ldnull(),
Ret(),
successLabel,
Ldtoken(moduleType),
Call("class System.Type System.Type::GetTypeFromHandle(valuetype System.RuntimeTypeHandle)"),
Callvirt("instance class System.Reflection.Assembly System.Type::get_Assembly()"),
Ldloc(resourceNameVariable),
Callvirt("instance class System.IO.Stream System.Reflection.Assembly::GetManifestResourceStream(string)"),
Ret());
programBuilder.Emit();
return(method);
}
private static MethodDefinition CreateAppDomainAssemblyResolveHandler(MethodReference getResourceAssemblyStreamOrNullMethod, MetadataHelper helper)
{
// C#:
// private static Assembly OnAssemblyResolve(object sender, ResolveEventArgs e)
// {
// using (var stream = GetResourceAssemblyStreamOrNull(new AssemblyName(e.Name)))
// {
// if (stream is null) return null;
//
// using (var buffer = new MemoryStream(capacity: checked((int)stream.Length)))
// {
// stream.CopyTo(buffer);
// return Assembly.Load(buffer.ToArray());
// }
// }
// }
var method = helper.DefineMethod(
"OnAssemblyResolve",
MethodAttributes.Private | MethodAttributes.Static | MethodAttributes.HideBySig,
returnType: "class System.Reflection.Assembly",
parameterTypes: new[] { "object", "class System.ResolveEventArgs" });
var program = new ProgramBuilder(method.Body, helper);
var streamLocal = program.CreateLocal("class System.IO.Stream");
var assemblyLocal = program.CreateLocal("class System.Reflection.Assembly");
var bufferLocal = program.CreateLocal("class System.IO.MemoryStream");
var skipReturningNullLabel = new Label();
var returnAssemblyLabel = new Label();
var skipInnerDispose = new Label();
var skipOuterDispose = new Label();
program.Append(
Ldarg(1),
Callvirt("instance string System.ResolveEventArgs::get_Name()"),
Newobj("instance void System.Reflection.AssemblyName::.ctor(string)"),
Call(getResourceAssemblyStreamOrNullMethod),
Stloc(streamLocal),
Try(
Ldloc(streamLocal),
Brtrue_S(skipReturningNullLabel),
Ldnull(),
Stloc(assemblyLocal),
Leave_S(returnAssemblyLabel),
skipReturningNullLabel,
Ldloc(streamLocal),
Callvirt("instance int64 System.IO.Stream::get_Length()"),
Conv_Ovf_I4(),
Newobj("instance void System.IO.MemoryStream::.ctor(int32)"),
Stloc(bufferLocal),
Try(
Ldloc(streamLocal),
Ldloc(bufferLocal),
Callvirt("instance void System.IO.Stream::CopyTo(class System.IO.Stream)"),
Ldloc(bufferLocal),
Callvirt("instance unsigned int8[] System.IO.MemoryStream::ToArray()"),
Call("class System.Reflection.Assembly System.Reflection.Assembly::Load(unsigned int8[])"),
Stloc(assemblyLocal),
Leave_S(returnAssemblyLabel))
.Finally(
Ldloc(bufferLocal),
Brfalse_S(skipInnerDispose),
Ldloc(bufferLocal),
Callvirt("instance void System.IDisposable::Dispose()"),
skipInnerDispose,
Endfinally()))
.Finally(
Ldloc(streamLocal),
Brfalse_S(skipOuterDispose),
Ldloc(streamLocal),
Callvirt("instance void System.IDisposable::Dispose()"),
skipOuterDispose,
Endfinally()),
returnAssemblyLabel,
Ldloc(assemblyLocal),
Ret());
program.Emit();
return(method);
}
private static MethodDefinition CreateAssemblyLoadContextAssemblyResolveHandler(MethodReference getResourceAssemblyStreamOrNullMethod, MetadataHelper helper)
{
// C#:
// private static Assembly Default_Resolving(AssemblyLoadContext context, AssemblyName name)
// {
// using (var stream = GetResourceAssemblyStreamOrNull(name))
// {
// if (stream is null) return null;
// return context.LoadFromStream(stream);
// }
// }
var method = helper.DefineMethod(
"OnAssemblyResolve",
MethodAttributes.Private | MethodAttributes.Static | MethodAttributes.HideBySig,
returnType: "class System.Reflection.Assembly",
parameterTypes: new[] { "object", "class System.ResolveEventArgs" });
var program = new ProgramBuilder(method.Body, helper);
var streamLocal = program.CreateLocal("class System.IO.Stream");
var assemblyLocal = program.CreateLocal("class System.Reflection.Assembly");
var skipReturningNullLabel = new Label();
var returnAssemblyLabel = new Label();
var skipDispose = new Label();
program.Append(
Ldarg(1),
Call(getResourceAssemblyStreamOrNullMethod),
Stloc(streamLocal),
Try(
Ldloc(streamLocal),
Brtrue_S(skipReturningNullLabel),
Ldnull(),
Stloc(assemblyLocal),
Leave_S(returnAssemblyLabel),
skipReturningNullLabel,
Ldarg(0),
Ldloc(streamLocal),
Callvirt(@"instance class System.Reflection.Assembly
class [System.Runtime.Loader]System.Runtime.Loader.AssemblyLoadContext::LoadFromStream(class System.IO.Stream)"),
Stloc(assemblyLocal),
Leave_S(returnAssemblyLabel))
.Finally(
Ldloc(streamLocal),
Brfalse_S(skipDispose),
Ldloc(streamLocal),
Callvirt("instance void System.IDisposable::Dispose()"),
skipDispose,
Endfinally()),
returnAssemblyLabel,
Ldloc(assemblyLocal),
Ret());
program.Emit();
return(method);
}