BizHawk/BizHawk.Emulation.Common/BizInvoke/BizInvoker.cs

481 lines
16 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;
using System.Reflection.Emit;
using System.Runtime.InteropServices;
using BizHawk.Common;
namespace BizHawk.Emulation.Common.BizInvoke
{
public static class BizInvoker
{
/// <summary>
/// holds information about a proxy implementation, including type and setup hooks
/// </summary>
private class InvokerImpl
{
public Type ImplType;
public List<Action<object, IImportResolver>> Hooks;
public Action<object, IMonitor> ConnectMonitor;
public object Create(IImportResolver dll, IMonitor monitor)
{
var ret = Activator.CreateInstance(ImplType);
foreach (var f in Hooks)
f(ret, dll);
if (ConnectMonitor != null)
ConnectMonitor(ret, monitor);
return ret;
}
}
/// <summary>
/// dictionary of all generated proxy implementations and their basetypes
/// </summary>
private static IDictionary<Type, InvokerImpl> Impls = new Dictionary<Type, InvokerImpl>();
/// <summary>
/// the assembly that all proxies are placed in
/// </summary>
private static readonly AssemblyBuilder ImplAssemblyBuilder;
/// <summary>
/// the module that all proxies are placed in
/// </summary>
private static readonly ModuleBuilder ImplModuleBilder;
static BizInvoker()
{
var aname = new AssemblyName("BizInvokeProxyAssembly");
ImplAssemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(aname, AssemblyBuilderAccess.Run);
ImplModuleBilder = ImplAssemblyBuilder.DefineDynamicModule("BizInvokerModule");
}
/// <summary>
/// get an implementation proxy for an interop class
/// </summary>
public static T GetInvoker<T>(IImportResolver dll)
where T : class
{
InvokerImpl impl;
lock (Impls)
{
var baseType = typeof(T);
if (!Impls.TryGetValue(baseType, out impl))
{
impl = CreateProxy(baseType, false);
Impls.Add(baseType, impl);
}
}
if (impl.ConnectMonitor != null)
throw new InvalidOperationException("Class was previously proxied with a monitor!");
return (T)impl.Create(dll, null);
}
public static T GetInvoker<T>(IImportResolver dll, IMonitor monitor)
where T : class
{
InvokerImpl impl;
lock (Impls)
{
var baseType = typeof(T);
if (!Impls.TryGetValue(baseType, out impl))
{
impl = CreateProxy(baseType, true);
Impls.Add(baseType, impl);
}
}
if (impl.ConnectMonitor == null)
throw new InvalidOperationException("Class was previously proxied without a monitor!");
return (T)impl.Create(dll, monitor);
}
private static InvokerImpl CreateProxy(Type baseType, bool monitor)
{
if (baseType.IsSealed)
throw new InvalidOperationException("Can't proxy a sealed type");
if (!baseType.IsPublic)
// the proxy type will be in a new assembly, so public is required here
throw new InvalidOperationException("Type must be public");
var baseConstructor = baseType.GetConstructor(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance, null, Type.EmptyTypes, null);
if (baseConstructor == null)
throw new InvalidOperationException("Base type must have a zero arg constructor");
var baseMethods = baseType.GetMethods(BindingFlags.Instance | BindingFlags.Public)
.Select(m => new
{
Info = m,
Attr = m.GetCustomAttributes(true).OfType<BizImportAttribute>().FirstOrDefault()
})
.Where(a => a.Attr != null)
.ToList();
if (baseMethods.Count == 0)
throw new InvalidOperationException("Couldn't find any [BizImport] methods to proxy");
{
var uo = baseMethods.FirstOrDefault(a => !a.Info.IsVirtual || a.Info.IsFinal);
if (uo != null)
throw new InvalidOperationException("Method " + uo.Info.Name + " cannot be overriden!");
// there's no technical reason to disallow this, but we wouldn't be doing anything
// with the base implementation, so it's probably a user error
var na = baseMethods.FirstOrDefault(a => !a.Info.IsAbstract);
if (na != null)
throw new InvalidOperationException("Method " + na.Info.Name + " is not abstract!");
}
// hooks that will be run on the created proxy object
var postCreateHooks = new List<Action<object, IImportResolver>>();
var type = ImplModuleBilder.DefineType("Bizhawk.BizInvokeProxy" + baseType.Name, TypeAttributes.Class | TypeAttributes.Public | TypeAttributes.Sealed, baseType);
var monitorField = monitor ? type.DefineField("MonitorField", typeof(IMonitor), FieldAttributes.Public) : null;
foreach (var mi in baseMethods)
{
var entryPointName = mi.Attr.EntryPoint ?? mi.Info.Name;
var hook = mi.Attr.Compatibility
? ImplementMethodDelegate(type, mi.Info, mi.Attr.CallingConvention, entryPointName, monitorField)
: ImplementMethodCalli(type, mi.Info, mi.Attr.CallingConvention, entryPointName, monitorField);
postCreateHooks.Add(hook);
}
var ret = new InvokerImpl
{
Hooks = postCreateHooks,
ImplType = type.CreateType()
};
if (monitor)
ret.ConnectMonitor = (o, m) => o.GetType().GetField(monitorField.Name).SetValue(o, m);
return ret;
}
/// <summary>
/// create a method implementation that uses GetDelegateForFunctionPointer internally
/// </summary>
private static Action<object, IImportResolver> ImplementMethodDelegate(TypeBuilder type, MethodInfo baseMethod, CallingConvention nativeCall, string entryPointName, FieldInfo monitorField)
{
var paramInfos = baseMethod.GetParameters();
var paramTypes = paramInfos.Select(p => p.ParameterType).ToArray();
var returnType = baseMethod.ReturnType;
// create the delegate type
var delegateType = type.DefineNestedType("DelegateType" + baseMethod.Name,
TypeAttributes.Class | TypeAttributes.NestedPrivate | TypeAttributes.Sealed, typeof(MulticastDelegate));
var delegateCtor = delegateType.DefineConstructor(
MethodAttributes.RTSpecialName | MethodAttributes.HideBySig | MethodAttributes.Public,
CallingConventions.Standard, new Type[] { typeof(object), typeof(IntPtr) });
delegateCtor.SetImplementationFlags(MethodImplAttributes.Runtime | MethodImplAttributes.Managed);
var delegateInvoke = delegateType.DefineMethod("Invoke",
MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.NewSlot | MethodAttributes.Virtual, returnType, paramTypes);
// we have to project all of the attributes from the baseMethod to the delegateInvoke
// so for something like [Out], the interop engine will see it and use it
for (int i = 0; i < paramInfos.Length; i++)
{
var p = delegateInvoke.DefineParameter(i + 1, ParameterAttributes.None, paramInfos[i].Name);
foreach (var a in paramInfos[i].GetCustomAttributes(false))
p.SetCustomAttribute(GetAttributeBuilder(a));
}
{
var p = delegateInvoke.DefineParameter(0, ParameterAttributes.Retval, baseMethod.ReturnParameter.Name);
foreach (var a in baseMethod.ReturnParameter.GetCustomAttributes(false))
p.SetCustomAttribute(GetAttributeBuilder(a));
}
delegateInvoke.SetImplementationFlags(MethodImplAttributes.Runtime | MethodImplAttributes.Managed);
// add the [UnmanagedFunctionPointer] to the delegate so interop will know how to call it
var attr = new CustomAttributeBuilder(typeof(UnmanagedFunctionPointerAttribute).GetConstructor(new[] { typeof(CallingConvention) }), new object[] { nativeCall });
delegateType.SetCustomAttribute(attr);
// define a field on the class to hold the delegate
var field = type.DefineField("DelegateField" + baseMethod.Name, delegateType,
FieldAttributes.Public);
var method = type.DefineMethod(baseMethod.Name, MethodAttributes.Virtual | MethodAttributes.Public,
CallingConventions.HasThis, returnType, paramTypes);
var il = method.GetILGenerator();
Label exc = new Label();
if (monitorField != null) // monitor: enter and then begin try
{
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, monitorField);
il.Emit(OpCodes.Callvirt, typeof(IMonitor).GetMethod("Enter"));
exc = il.BeginExceptionBlock();
}
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, field);
for (int i = 0; i < paramTypes.Length; i++)
il.Emit(OpCodes.Ldarg, (short)(i + 1));
il.Emit(OpCodes.Callvirt, delegateInvoke);
if (monitorField != null) // monitor: finally exit
{
LocalBuilder loc = null;
if (returnType != typeof(void))
{
loc = il.DeclareLocal(returnType);
il.Emit(OpCodes.Stloc, loc);
}
il.Emit(OpCodes.Leave, exc);
il.BeginFinallyBlock();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, monitorField);
il.Emit(OpCodes.Callvirt, typeof(IMonitor).GetMethod("Exit"));
il.EndExceptionBlock();
if (returnType != typeof(void))
{
il.Emit(OpCodes.Ldloc, loc);
}
}
il.Emit(OpCodes.Ret);
type.DefineMethodOverride(method, baseMethod);
return (o, dll) =>
{
var entryPtr = dll.SafeResolve(entryPointName);
var interopDelegate = Marshal.GetDelegateForFunctionPointer(entryPtr, delegateType.CreateType());
o.GetType().GetField(field.Name).SetValue(o, interopDelegate);
};
}
/// <summary>
/// create a method implementation that uses calli internally
/// </summary>
private static Action<object, IImportResolver> ImplementMethodCalli(TypeBuilder type, MethodInfo baseMethod, CallingConvention nativeCall, string entryPointName, FieldInfo monitorField)
{
var paramInfos = baseMethod.GetParameters();
var paramTypes = paramInfos.Select(p => p.ParameterType).ToArray();
var nativeParamTypes = new List<Type>();
var returnType = baseMethod.ReturnType;
if (returnType != typeof(void) && !returnType.IsPrimitive)
throw new InvalidOperationException("Only primitive return types are supported");
// define a field on the type to hold the entry pointer
var field = type.DefineField("EntryPtrField" + baseMethod.Name, typeof(IntPtr),
FieldAttributes.Public);
var method = type.DefineMethod(baseMethod.Name, MethodAttributes.Virtual | MethodAttributes.Public,
CallingConventions.HasThis, returnType, paramTypes);
var il = method.GetILGenerator();
Label exc = new Label();
if (monitorField != null) // monitor: enter and then begin try
{
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, monitorField);
il.Emit(OpCodes.Callvirt, typeof(IMonitor).GetMethod("Enter"));
exc = il.BeginExceptionBlock();
}
for (int i = 0; i < paramTypes.Length; i++)
{
// arg 0 is this, so + 1
nativeParamTypes.Add(EmitParamterLoad(il, i + 1, paramTypes[i]));
}
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, field);
il.EmitCalli(OpCodes.Calli, nativeCall, returnType, nativeParamTypes.ToArray());
if (monitorField != null) // monitor: finally exit
{
LocalBuilder loc = null;
if (returnType != typeof(void))
{
loc = il.DeclareLocal(returnType);
il.Emit(OpCodes.Stloc, loc);
}
il.Emit(OpCodes.Leave, exc);
il.BeginFinallyBlock();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Ldfld, monitorField);
il.Emit(OpCodes.Callvirt, typeof(IMonitor).GetMethod("Exit"));
il.EndExceptionBlock();
if (returnType != typeof(void))
{
il.Emit(OpCodes.Ldloc, loc);
}
}
// either there's a primitive on the stack and we're expected to return that primitive,
// or there's nothing on the stack and we're expected to return nothing
il.Emit(OpCodes.Ret);
type.DefineMethodOverride(method, baseMethod);
return (o, dll) =>
{
var entryPtr = dll.SafeResolve(entryPointName);
o.GetType().GetField(field.Name).SetValue(o, entryPtr);
};
}
/// <summary>
/// load an IntPtr constant in an il stream
/// </summary>
private static void LoadConstant(ILGenerator il, IntPtr p)
{
if (p == IntPtr.Zero)
il.Emit(OpCodes.Ldc_I4_0);
else if (IntPtr.Size == 4)
il.Emit(OpCodes.Ldc_I4, (int)p);
else
il.Emit(OpCodes.Ldc_I8, (long)p);
il.Emit(OpCodes.Conv_I);
}
/// <summary>
/// load a UIntPtr constant in an il stream
/// </summary>
private static void LoadConstant(ILGenerator il, UIntPtr p)
{
if (p == UIntPtr.Zero)
il.Emit(OpCodes.Ldc_I4_0);
else if (UIntPtr.Size == 4)
il.Emit(OpCodes.Ldc_I4, (int)p);
else
il.Emit(OpCodes.Ldc_I8, (long)p);
il.Emit(OpCodes.Conv_U);
}
/// <summary>
/// emit a single parameter load with unmanaged conversions
/// </summary>
private static Type EmitParamterLoad(ILGenerator il, int idx, Type type)
{
if (type.IsGenericType)
throw new InvalidOperationException("Generic types not supported");
if (type.IsByRef)
{
var et = type.GetElementType();
if (!et.IsPrimitive && !et.IsEnum)
throw new InvalidOperationException("Only refs of primitive or enum types are supported!");
var loc = il.DeclareLocal(type, true);
il.Emit(OpCodes.Ldarg, (short)idx);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc, loc);
il.Emit(OpCodes.Conv_I);
return typeof(IntPtr);
}
else if (type.IsArray)
{
var et = type.GetElementType();
if (!et.IsPrimitive && !et.IsEnum)
throw new InvalidOperationException("Only arrays of primitive or enum types are supported!");
// these two cases aren't too hard to add
if (type.GetArrayRank() > 1)
throw new InvalidOperationException("Multidimensional arrays are not supported!");
if (type.Name.Contains('*'))
throw new InvalidOperationException("Only 0-based 1-dimensional arrays are supported!");
var loc = il.DeclareLocal(type, true);
var end = il.DefineLabel();
var isNull = il.DefineLabel();
il.Emit(OpCodes.Ldarg, (short)idx);
il.Emit(OpCodes.Brfalse, isNull);
il.Emit(OpCodes.Ldarg, (short)idx);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc, loc);
il.Emit(OpCodes.Ldc_I4_0);
il.Emit(OpCodes.Ldelema, et);
il.Emit(OpCodes.Conv_I);
il.Emit(OpCodes.Br, end);
il.MarkLabel(isNull);
LoadConstant(il, IntPtr.Zero);
il.MarkLabel(end);
return typeof(IntPtr);
}
else if (typeof(Delegate).IsAssignableFrom(type))
{
var mi = typeof(Marshal).GetMethod("GetFunctionPointerForDelegate", new[] { typeof(Delegate) });
var end = il.DefineLabel();
var isNull = il.DefineLabel();
il.Emit(OpCodes.Ldarg, (short)idx);
il.Emit(OpCodes.Brfalse, isNull);
il.Emit(OpCodes.Ldarg, (short)idx);
il.Emit(OpCodes.Call, mi);
il.Emit(OpCodes.Br, end);
il.MarkLabel(isNull);
LoadConstant(il, IntPtr.Zero);
il.MarkLabel(end);
return typeof(IntPtr);
}
else if (type.IsPrimitive || type.IsEnum)
{
il.Emit(OpCodes.Ldarg, (short)idx);
return type;
}
else
{
throw new InvalidOperationException("Unrecognized parameter type!");
}
}
private static CustomAttributeBuilder GetAttributeBuilder(object o)
{
// anything more clever we can do here?
var t = o.GetType();
if (t == typeof(OutAttribute) || t == typeof(InAttribute))
return new CustomAttributeBuilder(t.GetConstructor(Type.EmptyTypes), new object[0]);
throw new InvalidOperationException("Unknown parameter attribute " + t.Name);
}
}
/// <summary>
/// mark an abstract method to be proxied by BizInvoker
/// </summary>
[AttributeUsage(AttributeTargets.Method)]
public class BizImportAttribute : Attribute
{
public CallingConvention CallingConvention
{
get { return _callingConvention; }
}
private readonly CallingConvention _callingConvention;
/// <summary>
/// name of entry point; if not given, the method's name is used
/// </summary>
public string EntryPoint { get; set; }
/// <summary>
/// Use a slower interop that supports more argument types
/// </summary>
public bool Compatibility { get; set; }
/// <summary>
///
/// </summary>
/// <param name="c">unmanaged calling convention</param>
public BizImportAttribute(CallingConvention c)
{
_callingConvention = c;
}
}
}