public static void TestNativeCallableValid()
{
/*
* void TestNativeCallable()
* {
* .locals init ([0] native int ptr)
* IL_0000: nop
* IL_0002: ldftn int32 CallbackMethod(native int,native int)
*
* IL_0012: stloc.0
* IL_0013: ldloc.0
* IL_0014: ldsfld native int [mscorlib]System.IntPtr::Zero
* IL_0019: call bool NativeMethods::EnumWindows(native int,
* native int)
* IL_001e: pop
* IL_001f: ret
* }
*/
DynamicMethod testNativeCallable = new DynamicMethod("TestNativeCallable", null, null, typeof(Program).Module);
ILGenerator il = testNativeCallable.GetILGenerator();
il.DeclareLocal(typeof(IntPtr));
il.Emit(OpCodes.Nop);
il.Emit(OpCodes.Ldftn, typeof(Program).GetMethod("CallbackMethod"));
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldsfld, typeof(IntPtr).GetField("Zero"));
il.Emit(OpCodes.Call, typeof(NativeMethods).GetMethod("EnumWindows"));
il.Emit(OpCodes.Pop);
il.Emit(OpCodes.Ret);
NativeMethodInvoker testNativeMethod = (NativeMethodInvoker)testNativeCallable.CreateDelegate(typeof(NativeMethodInvoker));
testNativeMethod();
}
/// <summary>
/// Call native method & process any exception
/// </summary>
/// <param name="nativeClient"></param>
/// <param name="serviceCode"></param>
/// <param name="opCode"></param>
/// <param name="argObject"></param>
/// <returns></returns>
public NativeMethodTransportObject InvokeNativeMethod(
INativeSession nativeClient,
int serviceCodeInt,
int opCodeInt,
NativeMethodTransportObject transportObject)
{
NativeMethodInvokerInstance = new NativeMethodInvoker();
NativeMethodTransportObject resultObject =
NativeMethodInvokerInstance.InvokeNativeMethod(
nativeClient,
serviceCodeInt,
opCodeInt,
transportObject);
return(resultObject);
}
/// <summary>
/// Call a service method and return result
/// </summary>
/// <param name="serviceCode"></param>
/// <param name="subServiceCode"></param>
/// <param name="parameters"></param>
/// <returns></returns>
public NativeMethodTransportObject CallServiceMethod(
ServiceCodes serviceCode,
object subServiceCode,
object parameters)
{
INativeSession nativeClient = CreateNativeSessionProxy();
NativeMethodInvokerInstance = new NativeMethodInvoker();
Services.Native.NativeMethodTransportObject resultObject =
NativeMethodInvokerInstance.InvokeNativeMethod(
nativeClient,
(int)serviceCode,
(int)subServiceCode,
new NativeMethodTransportObject(parameters));
((IClientChannel)nativeClient).Close();
return(resultObject);
}
public static void NegativeTest_ViaCalli()
{
Console.WriteLine($"{nameof(NegativeTest_ViaCalli)} function via calli instruction. The CLR _will_ crash.");
/*
* void TestUnmanagedCallersOnlyViaCalli()
* {
* .locals init (native int V_0)
* IL_0000: nop
* IL_0001: ldftn void CallbackViaCalli(int32)
* IL_0007: stloc.0
*
* IL_0008: ldc.i4 1234
* IL_000d: ldloc.0
* IL_000e: calli void(int32)
*
* IL_0013: nop
* IL_0014: ret
* }
*/
DynamicMethod testUnmanagedCallersOnly = new DynamicMethod("TestUnmanagedCallersOnlyViaCalli", null, null, typeof(Program).Module);
ILGenerator il = testUnmanagedCallersOnly.GetILGenerator();
il.DeclareLocal(typeof(IntPtr));
il.Emit(OpCodes.Nop);
// Get native function pointer of the callback
il.Emit(OpCodes.Ldftn, typeof(Program).GetMethod(nameof(CallbackViaCalli)));
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Ldc_I4, 1234);
il.Emit(OpCodes.Ldloc_0);
il.EmitCalli(OpCodes.Calli, CallingConventions.Standard, null, new Type[] { typeof(int) }, null);
il.Emit(OpCodes.Nop);
il.Emit(OpCodes.Ret);
NativeMethodInvoker testNativeMethod = (NativeMethodInvoker)testUnmanagedCallersOnly.CreateDelegate(typeof(NativeMethodInvoker));
// It is not possible to catch the resulting ExecutionEngineException exception.
// To observe the crashing behavior set a breakpoint in the ReversePInvokeBadTransition() function
// located in src/vm/dllimportcallback.cpp.
testNativeMethod();
}
public static void NegativeTest_ViaLdftn()
{
/*
* .locals init (native int V_0)
* IL_0000: nop
* IL_0001: ldftn void ConsoleApplication1.Program::callback(int32)
* IL_0007: stloc.0
* IL_0008: ldc.i4.s 12
* IL_000a: ldloc.0
* IL_000b: calli void(int32)
* IL_0010: nop
* IL_0011: ret
*/
DynamicMethod testNativeCallable = new DynamicMethod("TestNativeCallableLdftn", null, null, typeof(Program).Module);
ILGenerator il = testNativeCallable.GetILGenerator();
il.DeclareLocal(typeof(IntPtr));
il.Emit(OpCodes.Nop);
il.Emit(OpCodes.Ldftn, typeof(Program).GetMethod("LdftnCallback"));
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Ldc_I4, 12);
il.Emit(OpCodes.Ldloc_0);
SignatureHelper sig = SignatureHelper.GetMethodSigHelper(typeof(Program).Module, null, new Type[] { typeof(int) });
sig.AddArgument(typeof(int));
// il.EmitCalli is not available and the below is not correct
il.Emit(OpCodes.Calli, sig);
il.Emit(OpCodes.Nop);
il.Emit(OpCodes.Ret);
NativeMethodInvoker testNativeMethod = (NativeMethodInvoker)testNativeCallable.CreateDelegate(typeof(NativeMethodInvoker));
testNativeMethod();
}