/// <summary>
/// Create an adhoc variable used to retain an instance of an attribute.
/// </summary>
/// <param name="method">The method weaver.</param>
/// <param name="attribute">The attribute.</param>
/// <param name="member">The member.</param>
/// <returns></returns>
public Variable CreateAttributeAdhoc(MethodEmitter method, CustomAttribute attribute, MemberReference member)
{
var type = attribute.AttributeType;
var variable = method.EmitLocal(type);
var il = method.GetIL();
foreach (var arg in attribute.ConstructorArguments)
{
CreateAttributeParameter(method, attribute, arg);
}
il.Emit(Codes.Create(attribute.Constructor));
il.Emit(Codes.Store(variable));
if (attribute.HasInterface(Context.Finder.IInstanceAware) && !method.Target.IsStatic)
{
il.Emit(Codes.Load(variable));
il.Emit(Codes.This);
il.Emit(Codes.Invoke(Context.Finder.InstanceAwareInstanceSet));
}
foreach (var prop in attribute.Properties)
{
CreateAttributeProperty(method, attribute, variable, prop);
}
CreateAttributeRequirements(il, attribute, member, variable, false);
return(variable);
}
/// <summary>
/// Creates a property which replaces a provided field, and implements the <c>get</c> and <c>set</c> methods.
/// </summary>
/// <param name="emitter">The type emitter.</param>
/// <param name="field">The field.</param>
/// <returns></returns>
public PropertyEmitter CreateFieldProperty(TypeEmitter emitter, FieldDefinition field)
{
var variable = new Variable(field);
var property = emitter.EmitProperty(field.Name, field.FieldType, field.IsStatic);
var context = emitter.Context;
field.Name = $"<{field.Name}>k__BackingField";
context.AddCompilerGenerated(field);
context.AddNonSerialized(field);
var getter = property.GetGetter();
var gil = getter.GetIL();
gil.Emit(Codes.Nop);
gil.Emit(Codes.ThisIf(variable));
gil.Emit(Codes.Load(variable));
gil.Emit(Codes.Return);
getter.Body.InitLocals = true;
var setter = property.GetSetter();
var sil = setter.GetIL();
sil.Emit(Codes.Nop);
sil.Emit(Codes.ThisIf(variable));
sil.Emit(Codes.Arg(field.IsStatic ? 0 : 1));
sil.Emit(Codes.Store(variable));
sil.Emit(Codes.Return);
setter.Body.InitLocals = true;
return(property);
}
/// <summary>
/// Creates and populates any additional contract requirements of the attribute.
/// </summary>
/// <param name="il">The code emitter.</param>
/// <param name="attribute">The attribute.</param>
/// <param name="member">The member the attribute is associated with.</param>
/// <param name="variable">The variable containing the attribute.</param>
/// <param name="isStatic">Whether the attribute container is static.</param>
public void CreateAttributeRequirements(CodeEmitter il, CustomAttribute attribute, MemberReference member, Variable variable, bool isStatic)
{
if (attribute.HasInterface(Context.Finder.IMemberAware) && member != null)
{
il.Emit(Codes.ThisIf(variable));
il.Emit(Codes.Load(variable));
if (member is MethodReference method)
{
var minfo = CreateMethodInfo(new MethodEmitter(il.Parent.Parent, method));
il.Emit(Codes.ThisIf(minfo));
il.Emit(Codes.Load(minfo));
}
else if (member is PropertyReference property)
{
var pinfo = CreatePropertyInfo(new PropertyEmitter(il.Parent.Parent, property, isStatic));
il.Emit(Codes.ThisIf(pinfo));
il.Emit(Codes.Load(pinfo));
}
il.Emit(Codes.Invoke(Context.Finder.MemberAwareMemberSet));
}
if (attribute.HasInterface(Context.Finder.IRequireInitialization))
{
il.Emit(Codes.ThisIf(variable));
il.Emit(Codes.Load(variable));
il.Emit(Codes.Invoke(Context.Finder.RequireInitializationInitialize));
}
}
/// <summary>
/// Copies the values of an array of parameter values into the corresponding parameters.
/// </summary>
/// <param name="method">The method.</param>
/// <param name="array">The array.</param>
public void CopyArgumentArrayToParameters(MethodEmitter method, Variable array)
{
var parameters = method.Target.Parameters;
var count = parameters.Count;
var il = method.GetIL();
for (int i = 0; i < count; i++)
{
var p = parameters[i];
var variable = new Variable(p);
var type = p.ParameterType;
if (type.IsByReference || p.IsOut)
{
continue;
}
il.Emit(Codes.Load(array));
il.Emit(Codes.Int(i));
il.Emit(Codes.LoadArray);
il.Emit(Codes.Unbox(type));
il.Emit(Codes.Store(variable));
}
CopyArgumentArrayToReferences(method, array);
}
/// <summary>
/// Weaves an implementation of a property against the provided type.
/// </summary>
/// <param name="emitter">The emitter.</param>
/// <param name="field">The attribute field.</param>
/// <param name="property">The property.</param>
/// <param name="interfaceType">The type of the interface.</param>
public void WeaveImplementedProperty(TypeEmitter emitter, Variable field, PropertyDefinition property, TypeDefinition interfaceType)
{
var emitted = emitter.EmitProperty(property.Name, property.PropertyType.Import(), toBackingField: true);
var implemented = field.Type.GetProperty(property.Name, property.PropertyType)?.Resolve();
if (implemented == null)
{
implemented = field.Type.GetProperty($"{interfaceType.FullName}.{property.Name}", returnType: property.PropertyType)?.Resolve();
if (implemented == null)
{
throw new MissingMemberException($"Cannot implement '{field.Type.FullName}' as it does not implement property '{property.Name}'");
}
}
var source = new PropertyEmitter(emitter, implemented);
if (source.HasGetter && !emitted.HasGetter)
{
var getter = emitted.GetGetter();
var il = getter.GetIL();
var propertyGet = property.GetMethod?.Import() ?? implemented.GetMethod.Import();
getter.Body.SimplifyMacros();
il.Emit(Codes.Nop);
il.Emit(Codes.ThisIf(field));
il.Emit(Codes.Cast(interfaceType));
il.Emit(Codes.Load(field));
il.Emit(Codes.Invoke(propertyGet.GetGeneric()));
il.Emit(Codes.Return);
getter.Body.OptimizeMacros();
getter.Body.InitLocals = true;
}
if (source.HasSetter && !emitted.HasSetter)
{
var setter = emitted.GetSetter();
var il = setter.GetIL();
var propertySet = property.SetMethod?.Import() ?? implemented.SetMethod.Import();
setter.Body.SimplifyMacros();
il.Emit(Codes.Nop);
il.Emit(Codes.ThisIf(field));
il.Emit(Codes.Load(field));
il.Emit(Codes.Arg(setter.Target.IsStatic ? 0 : 1));
il.Emit(Codes.Invoke(propertySet.GetGeneric()));
il.Emit(Codes.Return);
setter.Body.OptimizeMacros();
setter.Body.InitLocals = true;
}
}
/// <summary>
/// Creates a reference to a parameter used in a custom attribute.
/// </summary>
/// <param name="emitter">The emitter.</param>
/// <param name="attribute">The attribute.</param>
/// <param name="arg">The argument.</param>
public void CreateAttributeParameter(MethodEmitter emitter, CustomAttribute attribute, CustomAttributeArgument arg)
{
var il = emitter.GetIL();
if (arg.Value == null)
{
il.Emit(Codes.Null);
return;
}
var type = arg.Type;
if (type.IsArray)
{
var elements = (arg.Value as IEnumerable).Cast <CustomAttributeArgument>().ToArray();
il.Emit(Codes.Int(elements.Length));
il.Emit(Codes.CreateArray(type.GetElementType()));
if (elements.Length == 0)
{
return;
}
il.Emit(Codes.Duplicate);
for (int i = 0, count = elements.Length; i < count; i++)
{
il.Emit(Codes.Int(i));
if (elements[i].Value == null)
{
il.Emit(Codes.Null);
il.Emit(Codes.StoreArray);
}
else
{
il.Emit(Codes.Load(elements[i].Value));
il.Emit(Codes.StoreArray);
}
if (i + 1 < count)
{
il.Emit(Codes.Duplicate);
}
}
}
else
{
il.Emit(Codes.Load(arg.Value));
}
}
/// <summary>
/// Creates an multi-instance-level field used to retain an instance of an attribute.
/// </summary>
/// <param name="emitter">The type weaver.</param>
/// <param name="attribute">The attribute.</param>
/// <param name="member">The member.</param>
/// <returns></returns>
public Variable CreateAttributeMultiInstanced(TypeEmitter emitter, CustomAttribute attribute, MemberReference member)
{
var index = Interlocked.Increment(ref id);
var type = attribute.AttributeType;
var name = $"<{type.Name}${index}>k__Attribute";
var existing = emitter.GetField(name, type, toStatic: false);
if (existing != null)
{
return(existing);
}
var field = emitter.EmitField(name, type);
foreach (var ctor in emitter.GetConstructors())
{
var il = ctor.GetIL();
il.Insert = CodeInsertion.Before;
il.Position = il.GetConstructorBaseOrThis()?.Next ?? il.GetFirst();
il.Emit(Codes.Nop);
il.Emit(Codes.This);
foreach (var arg in attribute.ConstructorArguments)
{
CreateAttributeParameter(ctor, attribute, arg);
}
il.Emit(Codes.Create(attribute.Constructor));
il.Emit(Codes.Store(field));
if (attribute.HasInterface(Context.Finder.IInstanceAware))
{
il.Emit(Codes.ThisIf(field));
il.Emit(Codes.Load(field));
il.Emit(Codes.This);
il.Emit(Codes.Invoke(Context.Finder.InstanceAwareInstanceSet));
}
foreach (var prop in attribute.Properties)
{
CreateAttributeProperty(ctor, attribute, field, prop);
}
CreateAttributeRequirements(il, attribute, member, field, false);
}
return(field);
}
/// <summary>
/// Creates a reference to a property used in a custom attribute.
/// </summary>
/// <param name="emitter">The emitter.</param>
/// <param name="attribute">The attribute.</param>
/// <param name="field">The attribute variable.</param>
/// <param name="property">The property.</param>
public void CreateAttributeProperty(MethodEmitter emitter, CustomAttribute attribute, Variable field, Mono.Cecil.CustomAttributeNamedArgument property)
{
var il = emitter.GetIL();
var member = field.Type.Resolve().Properties.FirstOrDefault(p => p.Name == property.Name)?.SetMethod;
if (member == null)
{
throw new MissingMemberException($"Cannot resolve property {property.Name} of {attribute.AttributeType.Name} as there is no setter");
}
il.Emit(Codes.ThisIf(field));
il.Emit(Codes.Load(field));
CreateAttributeParameter(emitter, attribute, property.Argument);
il.Emit(Codes.Invoke(member.Import()));
}
/// <summary>
/// Weaves the return instructions of the provided method to leave to a new instruction.
/// </summary>
/// <param name="weaver">The method weaver.</param>
/// <param name="storage">The storage variable for any captured return value.</param>
/// <param name="hasMethodInterceptors">Whether method interceptors are present which could change the return value.</param>
/// <returns>The instruction now located at the tail of the method.</returns>
public Instruction WeaveMethodReturnsRoute(MethodEmitter weaver, Variable storage, bool hasMethodInterceptors)
{
var il = weaver.Body.Instructions;
var pos = weaver.GetIL().Position;
var instruction = (Instruction)null;
if (weaver.Target.IsReturn())
{
instruction = hasMethodInterceptors ? Codes.Nop : Codes.Load(storage);
il.Add(instruction);
il.Add(Codes.Return);
for (int i = 0; i < il.Count - 2; i++)
{
if (il[i].OpCode == OpCodes.Ret)
{
var store = Codes.Store(storage);
il[i].OpCode = store.OpCode;
il[i].Operand = store.Operand;
weaver.Body.GetILProcessor().InsertAfter(il[i], Codes.Leave(instruction));
}
}
}
else
{
instruction = Codes.Return;
il.Add(instruction);
for (int i = 0, count = il.Count - 1; i < count; i++)
{
var ix = il[i];
if (ix.OpCode == OpCodes.Ret)
{
ix.OpCode = OpCodes.Leave;
ix.Operand = instruction;
}
}
}
return(instruction);
}
/// <summary>
/// Weave an implementation of a method against the provided type.
/// </summary>
/// <param name="emitter">The emitter.</param>
/// <param name="field">The attribute field.</param>
/// <param name="method">The method.</param>
/// <param name="interfaceType">The type of the interface.</param>
public void WeaveImplementedMethod(TypeEmitter emitter, Variable field, MethodReference method, TypeDefinition interfaceType)
{
var resolved = method.Resolve();
var emitted = emitter.EmitMethod(
method.Name,
method.ReturnType.Import(),
parameterTypes: method.HasParameters ? method.Parameters.Select(p => p.ParameterType.Import()).ToArray() : new TypeReference[0],
genericTypes: method.HasGenericParameters ? method.GenericParameters.ToArray() : new GenericParameter[0],
toStatic: resolved.IsStatic,
toVisibility: resolved.GetVisiblity()
);
var parameters = method.Parameters.Select(p => p.ParameterType).ToArray();
var generics = method.GenericParameters.ToArray();
var implemented = field.Type.GetMethod(method.Name, returns: method.ReturnType, parameters: parameters, generics: generics);
if (implemented == null)
{
implemented = field.Type.GetMethod($"{interfaceType.FullName}.{method.Name}", returns: method.ReturnType, parameters: parameters, generics: generics);
if (implemented == null)
{
throw new MissingMemberException($"Cannot implement '{field.Type.FullName}' as it does not implement method '{method.FullName}'");
}
}
var il = emitted.GetIL();
il.Emit(Codes.Nop);
il.Emit(Codes.ThisIf(field));
il.Emit(Codes.Load(field));
for (int i = 0, count = method.Parameters.Count; i < count; i++)
{
il.Emit(Codes.Arg(i + 1));
}
il.Emit(Codes.Invoke(method.Import().GetGeneric()));
il.Emit(Codes.Return);
emitted.Body.InitLocals = true;
}
/// <summary>
/// Copies the values of an array of parameter values into the required references.
/// </summary>
/// <param name="method">The method.</param>
/// <param name="array">The array.</param>
public void CopyArgumentArrayToReferences(MethodEmitter method, Variable array)
{
var parameters = method.Target.Parameters;
var count = parameters.Count;
var il = method.GetIL();
for (int i = 0; i < count; i++)
{
var p = parameters[i];
var type = p.ParameterType;
if (!type.IsByReference || p.IsOut)
{
continue;
}
var spec = (TypeSpecification)type;
var unboxing = true;
il.Emit(Codes.Arg(p));
il.Emit(Codes.Load(array));
il.Emit(Codes.Int(i));
il.Emit(Codes.LoadArray);
var code = OpCodes.Nop;
switch (spec.ElementType.MetadataType)
{
case MetadataType.Boolean:
case MetadataType.SByte:
case MetadataType.Byte:
code = OpCodes.Stind_I1;
break;
case MetadataType.Int16:
case MetadataType.UInt16:
code = OpCodes.Stind_I2;
break;
case MetadataType.Int32:
case MetadataType.UInt32:
code = OpCodes.Stind_I4;
break;
case MetadataType.Int64:
case MetadataType.UInt64:
code = OpCodes.Stind_I8;
break;
case MetadataType.Single:
code = OpCodes.Stind_R4;
break;
case MetadataType.Double:
code = OpCodes.Stind_R8;
break;
case MetadataType.IntPtr:
case MetadataType.UIntPtr:
code = OpCodes.Stind_I;
break;
default:
if (spec.ElementType.IsValueType)
{
il.Emit(Instruction.Create(OpCodes.Stobj, spec.ElementType));
}
else
{
code = OpCodes.Stind_Ref;
unboxing = false;
}
break;
}
if (unboxing)
{
il.Emit(Codes.Unbox(spec.ElementType));
}
if (code != OpCodes.Nop)
{
il.Emit(code);
}
}
}
/// <summary>
/// Create an array variable containing the arguments of the method invocation.
/// </summary>
/// <param name="method">The method weaver.</param>
/// <returns></returns>
public Variable CreateArgumentArray(MethodEmitter method)
{
var parameters = method.Target.Parameters;
var count = parameters.Count;
var array = method.EmitLocal(Context.Finder.ObjectArray);
var il = method.GetIL();
il.Emit(Codes.Nop);
il.Emit(Codes.Int(count));
il.Emit(Codes.CreateArray(TypeSystem.ObjectReference));
il.Emit(Codes.Store(array));
for (int i = 0; i < count; i++)
{
var p = parameters[i];
var type = p.ParameterType;
il.Emit(Codes.Load(array));
il.Emit(Codes.Int(i));
if (p.IsOut)
{
var spec = (TypeSpecification)type;
if (spec.ElementType.IsValueType)
{
il.Emit(Codes.Init(spec.ElementType));
}
else
{
il.Emit(Codes.Null);
il.Emit(Codes.StoreArray);
}
continue;
}
il.Emit(Codes.Arg(p));
if (type.IsByReference)
{
var spec = (TypeSpecification)type;
var boxing = true;
switch (spec.ElementType.MetadataType)
{
case MetadataType.SByte:
il.Emit(OpCodes.Ldind_I1);
break;
case MetadataType.Int16:
il.Emit(OpCodes.Ldind_I2);
break;
case MetadataType.Int32:
il.Emit(OpCodes.Ldind_I4);
break;
case MetadataType.Int64:
case MetadataType.UInt64:
il.Emit(OpCodes.Ldind_I8);
break;
case MetadataType.Boolean:
case MetadataType.Byte:
il.Emit(OpCodes.Ldind_U1);
break;
case MetadataType.UInt16:
il.Emit(OpCodes.Ldind_U2);
break;
case MetadataType.UInt32:
il.Emit(OpCodes.Ldind_U4);
break;
case MetadataType.Single:
il.Emit(OpCodes.Ldind_R4);
break;
case MetadataType.Double:
il.Emit(OpCodes.Ldind_R8);
break;
case MetadataType.IntPtr:
case MetadataType.UIntPtr:
il.Emit(OpCodes.Ldind_I);
break;
default:
if (spec.ElementType.IsValueType)
{
il.Emit(Instruction.Create(OpCodes.Ldobj, spec.ElementType));
}
else
{
il.Emit(OpCodes.Ldind_Ref);
boxing = false;
}
break;
}
if (boxing)
{
il.Emit(Codes.Box(spec.ElementType));
}
}
else
{
il.Emit(Codes.Box(p.ParameterType));
}
il.Emit(Codes.StoreArray);
}
return(array);
}
/// <summary>
/// Weaves the constructor interceptors for a provided type and interceptor information.
/// </summary>
/// <param name="weaver">The weaver.</param>
/// <param name="item">The interceptors.</param>
public void WeaveConstructorInterceptors(TypeEmitter weaver, ConstructorInterceptorInfo item)
{
var constructors = weaver.GetConstructors();
foreach (var init in item.Initializers)
{
var parameters = init.Parameters;
if (parameters.Any(p => !p.IsOptional))
{
throw new NotSupportedException($"Cannot use constructor injection against a method with non-optional parameters");
}
var after = init.GetAttribute(Context.Finder.IInjectAfterInitializer);
var before = init.GetAttribute(Context.Finder.IInjectBeforeInitializer);
if (init.HasGenericParameters)
{
throw new NotSupportedException($"Cannot use constructor injection against a generic method");
}
foreach (var ctor in constructors)
{
var il = ctor.GetIL();
var st = init.IsStatic;
il.Body.SimplifyMacros();
il.Insert = CodeInsertion.Before;
il.Position = before != null ? (il.GetConstructorBaseOrThis()?.Next ?? il.GetFirst()) : il.GetLast();
if (!st)
{
il.Emit(Codes.This);
}
var type = ctor.Parent.Target.GetGeneric();
var method = (MethodReference)init;
if (type.IsGenericInstance)
{
var generic = (GenericInstanceType)type;
method = init.MakeGeneric(generic.GenericArguments.ToArray());
}
foreach (var param in parameters)
{
il.Emit(Codes.Load(param.Constant));
}
il.Emit(st ? Codes.InvokeStatic(method) : Codes.Invoke(method));
if (method.IsReturn())
{
il.Emit(Codes.Pop);
}
il.Body.InitLocals = true;
il.Body.OptimizeMacros();
}
if (after != null)
{
init.CustomAttributes.Remove(after);
}
if (before != null)
{
init.CustomAttributes.Remove(before);
}
}
}
/// <summary>
/// Weave an implementation of an event against the provided type.
/// </summary>
/// <param name="emitter">The emitter.</param>
/// <param name="field">The attribute field.</param>
/// <param name="evt">The event.</param>
/// <param name="interfaceType">The type of the interface.</param>
public void WeaveImplementedEvent(TypeEmitter emitter, Variable field, EventReference evt, TypeDefinition interfaceType)
{
var implemented = field.Type.GetEvent(evt.Name, evt.EventType);
if (implemented == null)
{
implemented = field.Type.GetEvent($"{interfaceType.FullName}.{evt.Name}", evt.EventType);
if (implemented == null)
{
throw new MissingMemberException($"Cannot implement '{field.Type.FullName}' as it does not implement event '{evt.Name}'");
}
}
var emitted = emitter.EmitEvent(evt.Name, implemented.EventType);
var definition = evt.Resolve() ?? implemented.Resolve();
var hasAdd = emitted.HasAdd;
var add = emitted.GetAdd();
if (!hasAdd)
{
add.Body.SimplifyMacros();
var ail = add.GetIL();
var interfaceAdd = definition.AddMethod.Import();
ail.Emit(Codes.Nop);
ail.Emit(Codes.ThisIf(field));
ail.Emit(Codes.Load(field));
ail.Emit(Codes.Arg(add.IsStatic ? 0 : 1));
ail.Emit(Codes.Invoke(interfaceAdd.GetGeneric()));
ail.Emit(Codes.Return);
add.Body.OptimizeMacros();
}
add.Body.InitLocals = true;
var hasRemove = emitted.HasRemove;
var remove = emitted.GetRemove();
if (!emitted.HasRemove)
{
remove.Body.SimplifyMacros();
var ril = remove.GetIL();
var interfaceRemove = definition.RemoveMethod.Import();
ril.Emit(Codes.Nop);
ril.Emit(Codes.ThisIf(field));
ril.Emit(Codes.Load(field));
ril.Emit(Codes.Arg(remove.IsStatic ? 0 : 1));
ril.Emit(Codes.Invoke(interfaceRemove.GetGeneric()));
ril.Emit(Codes.Return);
remove.Body.OptimizeMacros();
}
remove.Body.InitLocals = true;
}
/// <summary>
/// Weaves the interception logic of a property.
/// </summary>
/// <param name="parent"></param>
/// <param name="item"></param>
public void WeavePropertyInterceptors(TypeEmitter parent, PropertyInterceptorInfo item)
{
var property = item.Property;
var getter = property.GetMethod != null ? new MethodEmitter(parent, property.GetMethod) : null;
var setter = property.SetMethod != null ? new MethodEmitter(parent, property.SetMethod) : null;
var count = item.Interceptors.Length;
var weaver = new PropertyEmitter(parent, property);
if (count == 0)
{
return;
}
var gInterceptors = new Variable[count];
var sInterceptors = new Variable[count];
for (int i = 0; i < count; i++)
{
var variables = CreateAttribute(weaver, getter, setter, item.Interceptors[i], item.Field);
gInterceptors[i] = variables[0];
sInterceptors[i] = variables[1];
}
var hasGetter = gInterceptors.Any(i => i != null);
var hasSetter = sInterceptors.Any(i => i != null);
var type = property.PropertyType;
var info = CreatePropertyInfo(weaver);
var field = property.GetBackingField();
var backing = (Variable)null;
if (field != null)
{
var def = field.Resolve();
def.Attributes &= ~Mono.Cecil.FieldAttributes.InitOnly;
backing = new Variable(def);
}
if (getter != null && hasGetter)
{
var il = getter.GetIL();
var result = getter.EmitLocal(property.PropertyType);
il.Body.SimplifyMacros();
il.Position = il.GetFirst();
il.Insert = CodeInsertion.Before;
if (backing != null)
{
il.Emit(Codes.ThisIf(backing));
il.Emit(Codes.Load(backing));
il.Emit(Codes.Store(result));
}
else
{
if (type.IsValueType)
{
il.Emit(Codes.Address(result));
il.Emit(Codes.Init(type));
}
else
{
il.Emit(Codes.Null);
il.Emit(Codes.Store(result));
}
}
il.Try();
var leave = WeaveMethodReturnsRoute(getter, result, true);
var cancel = il.EmitLabel();
var args = il.EmitLocal(Context.Finder.PropertyInterceptionArgs);
il.Emit(getter.Target.IsStatic ? Codes.Null : Codes.This);
il.Emit(Codes.Load(info));
il.Emit(Codes.Load(result));
il.Emit(Codes.Box(type));
il.Emit(Codes.Create(Context.Finder.PropertyInterceptionArgsCtor));
il.Emit(Codes.Store(args));
for (int i = 0; i < count; i++)
{
var inc = gInterceptors[i];
if (inc == null)
{
continue;
}
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyGetInterceptorOnGet));
}
il.Position = leave;
il.Finally();
for (int i = 0; i < count; i++)
{
var inc = gInterceptors[i];
if (inc == null)
{
continue;
}
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyGetInterceptorOnExit));
}
il.Mark(cancel);
il.EndTry();
il.Insert = CodeInsertion.After;
if (setter != null || backing != null)
{
var unchanged = il.EmitLabel();
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyInterceptionArgsIsDirtyGet));
il.Emit(Codes.IfFalse(unchanged));
if (!getter.Target.IsStatic)
{
il.Emit(Codes.This);
}
if (backing == null)
{
var pcount = setter.Target.Parameters.Count - 1;
for (int i = 0; i < pcount; i++)
{
il.Emit(Codes.Arg(setter.Target.Parameters[i]));
}
}
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyInterceptionArgsValueGet));
il.Emit(Codes.Unbox(type));
if (backing != null)
{
il.Emit(Codes.Store(backing));
}
else
{
il.Emit(Codes.Invoke(setter.Target));
}
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyInterceptionArgsValueGet));
il.Emit(Codes.Unbox(type));
il.Emit(Codes.Store(result));
il.Emit(Codes.Nop);
il.Mark(unchanged);
}
il.Emit(Codes.Load(result));
il.Body.InitLocals = true;
il.Body.OptimizeMacros();
}
if (setter != null && hasSetter)
{
var il = setter.GetIL();
il.Body.SimplifyMacros();
il.Position = il.GetFirst();
il.Insert = CodeInsertion.Before;
var args = il.EmitLocal(Context.Finder.PropertyInterceptionArgs);
var cancel = il.EmitLabel();
var argument = new Variable(setter.Target.Parameters.Last());
il.Try();
il.Emit(setter.Target.IsStatic ? Codes.Null : Codes.This);
il.Emit(Codes.Load(info));
il.Emit(Codes.Load(argument));
il.Emit(Codes.Box(type));
il.Emit(Codes.Create(Context.Finder.PropertyInterceptionArgsCtor));
il.Emit(Codes.Store(args));
for (int i = 0; i < count; i++)
{
var inc = sInterceptors[i];
if (inc == null)
{
continue;
}
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertySetInterceptorOnSet));
}
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyInterceptionArgsIsDirtyGet));
il.Emit(Codes.IfFalse(cancel));
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertyInterceptionArgsValueGet));
il.Emit(Codes.Unbox(argument.Type));
il.Emit(Codes.Store(argument));
il.Emit(Codes.Nop);
il.Position = il.Position.Previous;
il.Mark(cancel);
il.Position = il.GetLast();
il.Emit(Codes.Leave(il.Position));
il.Finally();
for (int i = 0; i < count; i++)
{
var inc = sInterceptors[i];
if (inc == null)
{
continue;
}
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
il.Emit(Codes.Load(args));
il.Emit(Codes.Invoke(Context.Finder.PropertySetInterceptorOnExit));
}
il.EndTry();
il.Body.InitLocals = true;
il.Body.OptimizeMacros();
}
}
public Startup(IConfiguration configuration)
{
Configuration = configuration;
Codes.Load();
}
/// <summary>
/// Weaves the interception logic of a method.
/// </summary>
/// <param name="weaver">The method weaver.</param>
/// <param name="item">The method information.</param>
public void WeaveMethodInterceptors(MethodEmitter weaver, MethodInterceptorInfo item)
{
weaver.Body.SimplifyMacros();
var pAttributes = item.Parameters.SelectMany(p => p.Attributes.Select(a => new { p.Index, Attribute = a })).ToArray();
var mAttributes = item.MethodInterceptors;
var rAttributes = item.ReturnInterceptors;
var pInterceptors = new Variable[pAttributes.Length];
var mInterceptors = new Variable[item.MethodInterceptors.Length];
var rInterceptors = new Variable[rAttributes.Length];
var needsEnter = mAttributes.Any(m => m.HasRequiredMethod(Context.Finder.MethodInterceptorOnEnter));
var needsCatch = mAttributes.Any(m => m.HasRequiredMethod(Context.Finder.MethodInterceptorOnException));
var needsExit = mAttributes.Any(m => m.HasRequiredMethod(Context.Finder.MethodInterceptorOnExit));
var needsParams = pAttributes.Any(m => m.Attribute.HasRequiredMethod(Context.Finder.ParameterInterceptorOnEnter));
var needsReturns = rAttributes.Any(m => m.HasRequiredMethod(Context.Finder.MethodReturnInterceptorOnReturn));
var needsMethodArgs = mAttributes.Any(m =>
{
return(m.AttributeType.GetMethod(Context.Finder.MethodInterceptorOnEnter).UsesParameter(0) ||
m.AttributeType.GetMethod(Context.Finder.MethodInterceptorOnException).UsesParameter(0) ||
m.AttributeType.GetMethod(Context.Finder.MethodInterceptorOnExit).UsesParameter(0));
});
var needsParamArgs = pAttributes.Any(m => m.Attribute.AttributeType.GetMethod(Context.Finder.ParameterInterceptorOnEnter).UsesParameter(0));
var needsReturnsArgs = rAttributes.Any(m => m.AttributeType.GetMethod(Context.Finder.MethodReturnInterceptorOnReturn).UsesParameter(0));
var needsMethodCopyArgs = mAttributes.Any(m => m.GetAttribute(Context.Finder.CompilationOptionsAttribute)?.GetProperty("CopyArguments", notFound: false) ?? false);
if (!needsEnter && !needsCatch && !needsExit && !needsParams && !needsReturns)
{
return;
}
var method = weaver.Target;
var il = weaver.GetIL();
il.Position = il.GetFirst();
il.Insert = CodeInsertion.Before;
var result = (Variable)null;
if (weaver.Target.IsReturn())
{
var type = weaver.Target.ReturnType;
result = weaver.EmitLocal(type);
if (type.IsValueType)
{
il.Emit(Codes.Address(result));
il.Emit(Codes.Init(type));
}
else
{
il.Emit(Codes.Null);
il.Emit(Codes.Store(result));
}
}
var leave = WeaveMethodReturnsRoute(weaver, result, mInterceptors.Length > 0);
var cancel = il.EmitLabel();
for (int i = 0, count = pInterceptors.Length; i < count; i++)
{
pInterceptors[i] = CreateAttribute(weaver, pAttributes[i].Attribute);
}
for (int i = 0, count = mInterceptors.Length; i < count; i++)
{
mInterceptors[i] = CreateAttribute(weaver, mAttributes[i]);
}
for (int i = 0, count = rInterceptors.Length; i < count; i++)
{
rInterceptors[i] = CreateAttribute(weaver, rAttributes[i]);
}
foreach (var attribute in mAttributes)
{
weaver.Target.CustomAttributes.Remove(attribute);
}
foreach (var attribute in pAttributes)
{
if (attribute.Index == -1)
{
weaver.Target.CustomAttributes.Remove(attribute.Attribute);
}
else
{
weaver.Target.Parameters[attribute.Index].CustomAttributes.Remove(attribute.Attribute);
}
}
foreach (var attribute in rAttributes)
{
weaver.Target.MethodReturnType.CustomAttributes.Remove(attribute);
}
foreach (var parameter in item.Parameters)
{
foreach (var attribute in parameter.Attributes)
{
if (parameter.Index == -1)
{
weaver.Target.CustomAttributes.Remove(attribute);
}
else
{
weaver.Target.Parameters[parameter.Index].CustomAttributes.Remove(attribute);
}
}
}
var hasMethod = mInterceptors.Length > 0;
var hasParams = pInterceptors.Length > 0;
var hasReturn = rInterceptors.Length > 0;
var arguments = hasMethod ? CreateArgumentArray(weaver) : null;
var invocation = CreateMethodInfo(weaver);
var mEventArgs = hasMethod && needsMethodArgs?weaver.EmitLocal(Context.Finder.MethodInterceptionArgs, name : "methodEventArgs") : null;
if (hasMethod || hasReturn)
{
if (hasMethod && needsMethodArgs)
{
il.Emit(method.IsStatic ? Codes.Null : Codes.This);
il.Emit(Codes.Load(arguments));
if (result == null)
{
il.Emit(Codes.Null);
}
else
{
il.Emit(Codes.Load(result));
il.Emit(Codes.Box(result.Type));
}
il.Emit(Codes.Load(invocation));
il.Emit(Codes.Create(Context.Finder.MethodInterceptionArgsCtor));
il.Emit(Codes.Store(mEventArgs));
}
il.Try();
}
if (hasParams && needsParams)
{
var pEventArgs = needsParamArgs ? weaver.EmitLocal(Context.Finder.ParameterInterceptionArgs) : null;
for (int i = 0, count = pInterceptors.Length; i < count; i++)
{
var inc = pInterceptors[i];
var parameters = pAttributes[i].Index == -1 ? method.Parameters.ToArray() : new[] { method.Parameters[pAttributes[i].Index] };
for (int j = 0, pCount = parameters.Length; j < pCount; j++)
{
var prm = parameters[j];
var pVariable = new Variable(prm);
var pInfo = CreateParameterInfo(weaver, prm);
var needsCopyArgs = pAttributes[i].Attribute.GetAttribute(Context.Finder.CompilationOptionsAttribute)?.GetProperty("CopyArguments", notFound: false) ?? false;
if (needsParamArgs)
{
il.Emit(method.IsStatic ? Codes.Null : Codes.This);
il.Emit(Codes.Load(pInfo));
il.Emit(Codes.Arg(pVariable));
il.Emit(Codes.Box(prm.ParameterType));
il.Emit(Codes.Create(Context.Finder.ParameterInterceptionArgsCtor));
il.Emit(Codes.Store(pEventArgs));
}
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
if (needsParamArgs)
{
il.Emit(Codes.Load(pEventArgs));
}
else
{
il.Emit(Codes.Null);
}
il.Emit(Codes.Invoke(Context.Finder.ParameterInterceptorOnEnter));
if (needsParamArgs && !prm.IsOut && needsCopyArgs)
{
il.Emit(Codes.Load(pEventArgs));
il.Emit(Codes.Invoke(Context.Finder.ParameterInterceptionArgsValueGet));
il.Emit(Codes.Unbox(prm.ParameterType));
il.Emit(Codes.Store(pVariable));
}
}
}
}
if (hasMethod || hasReturn)
{
if (hasMethod && needsEnter)
{
for (int i = 0, count = mInterceptors.Length; i < count; i++)
{
var inc = mInterceptors[i];
var att = mAttributes[i];
if (att.HasRequiredMethod("OnEnter"))
{
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
if (needsMethodArgs)
{
il.Emit(Codes.Load(mEventArgs));
}
else
{
il.Emit(Codes.Null);
}
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptorOnEnter));
if (needsMethodArgs)
{
var proceed = il.EmitLabel();
il.Emit(Codes.Load(mEventArgs));
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptionArgsCancelGet));
il.Emit(Codes.IfFalse(proceed));
if (result != null && needsMethodArgs)
{
il.Emit(Codes.Load(mEventArgs));
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptionArgsReturnGet));
il.Emit(Codes.Unbox(result.Type));
il.Emit(Codes.Store(result));
}
il.Emit(Codes.Leave(leave));
il.Mark(proceed);
}
}
}
if (needsMethodArgs && needsMethodCopyArgs && arguments != null)
{
CopyArgumentArrayToParameters(weaver, arguments);
}
}
il.Position = leave;
if (hasMethod && needsCatch)
{
var exception = il.EmitLocal(Context.Finder.Exception);
il.Catch(exception);
for (int i = 0, count = mInterceptors.Length; i < count; i++)
{
var inc = mInterceptors[i];
var att = mAttributes[i];
if (att.HasRequiredMethod("OnException"))
{
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
if (needsMethodArgs)
{
il.Emit(Codes.Load(mEventArgs));
}
else
{
il.Emit(Codes.Null);
}
il.Emit(Codes.Load(exception));
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptorOnException));
}
}
if (needsExit || needsReturns)
{
il.Emit(Codes.Nop);
il.Emit(Codes.Leave(leave));
}
}
if (needsExit || needsReturns)
{
il.Finally(leave);
}
if (hasMethod)
{
if (result != null && needsMethodArgs)
{
il.Emit(Codes.Load(mEventArgs));
il.Emit(Codes.Load(result));
il.Emit(Codes.Box(weaver.Target.ReturnType));
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptionArgsReturnSet));
}
if (needsExit)
{
for (int i = 0, count = mInterceptors.Length; i < count; i++)
{
var inc = mInterceptors[i];
var att = mAttributes[i];
if (att.HasRequiredMethod("OnExit"))
{
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
if (needsMethodArgs)
{
il.Emit(Codes.Load(mEventArgs));
}
else
{
il.Emit(Codes.Null);
}
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptorOnExit));
}
}
}
il.Mark(cancel);
}
if (hasReturn && needsReturns && result != null)
{
var rEventArgs = needsReturnsArgs ? il.EmitLocal(Context.Finder.MethodReturnInterceptionArgs) : null;
if (needsReturnsArgs)
{
il.Emit(method.IsStatic ? Codes.Null : Codes.This);
il.Emit(Codes.Load(result));
il.Emit(Codes.Box(result.Type));
il.Emit(Codes.Load(invocation));
il.Emit(Codes.Create(Context.Finder.MethodReturnInterceptionArgsCtor));
il.Emit(Codes.Store(rEventArgs));
}
for (int i = 0, count = rInterceptors.Length; i < count; i++)
{
var inc = rInterceptors[i];
var att = rAttributes[i];
if (att.HasRequiredMethod("OnReturn"))
{
il.Emit(Codes.ThisIf(inc));
il.Emit(Codes.Load(inc));
if (needsReturnsArgs)
{
il.Emit(Codes.Load(rEventArgs));
}
else
{
il.Emit(Codes.Null);
}
il.Emit(Codes.Invoke(Context.Finder.MethodReturnInterceptorOnReturn));
}
}
if (needsReturnsArgs)
{
il.Emit(Codes.Load(rEventArgs));
il.Emit(Codes.Invoke(Context.Finder.MethodReturnInterceptionArgsValueGet));
il.Emit(Codes.Unbox(result.Type));
il.Emit(Codes.Store(result));
}
}
if (!needsExit && !needsReturns)
{
il.Emit(Codes.Nop);
il.Emit(Codes.Leave(leave));
}
il.EndTry();
il.Insert = CodeInsertion.After;
if (hasMethod && arguments != null)
{
CopyArgumentArrayToReferences(weaver, arguments);
}
if (hasMethod && needsMethodArgs && result != null)
{
il.Emit(Codes.Nop);
il.Emit(Codes.Load(mEventArgs));
il.Emit(Codes.Invoke(Context.Finder.MethodInterceptionArgsReturnGet));
il.Emit(Codes.Unbox(weaver.Target.ReturnType));
}
else if (hasMethod && result != null)
{
il.Emit(Codes.Nop);
il.Emit(Codes.Load(result));
}
}
weaver.Body.InitLocals = true;
weaver.Body.OptimizeMacros();
}