public static Delegate LoadFunc(INativeLibImporter importer, IntPtr libraryHandle, string entryPoint, Type delegateType)
{
IntPtr procAddress = importer.GetProcAddress(libraryHandle, entryPoint);
if (procAddress == IntPtr.Zero)
{
throw new EntryPointNotFoundException(string.Format("Unable to get address of {0} ({1})", entryPoint, delegateType));
}
return(Marshal.GetDelegateForFunctionPointer(procAddress, delegateType));
}
public static T LoadFunc <T>(INativeLibImporter importer, IntPtr libraryHandle, string entryPoint)
{
IntPtr procAddress = importer.GetProcAddress(libraryHandle, entryPoint);
if (procAddress == IntPtr.Zero)
{
throw new NativeLoadException(string.Format("Unable to get address of {0} ({1})", entryPoint, typeof(T)), null);
}
return(CurrentFramework.GetDelegateForFunctionPointer <T>(procAddress));
}
static object GetDelegate(INativeLibImporter importer, IntPtr lib, string entryPoint, Type delegateType)
{
IntPtr procAddress = importer.GetProcAddress(lib, entryPoint);
if (procAddress == IntPtr.Zero)
{
return(null);
}
var method = typeof(CurrentFramework).GetTypeInfo().GetMethod(nameof(CurrentFramework.GetDelegateForFunctionPointer)).MakeGenericMethod(delegateType);
return(method.Invoke(null, new object[] { procAddress }));
}
static object GetDelegate(INativeLibImporter importer, IntPtr lib, string entryPoint, Type delegateType)
{
IntPtr procAddress = importer.GetProcAddress(lib, entryPoint);
if (procAddress == IntPtr.Zero)
{
var invokeMethod = delegateType.GetTypeInfo().GetMethod("Invoke");
var parameters = invokeMethod.GetParameters().Select(p => Expression.Parameter(p.ParameterType)).ToArray();
var returnType = invokeMethod.ReturnType;
var errorMessage = string.Format("Unable to get address of {0} ({1})", entryPoint, delegateType);
Action throwAction = () => throw new NativeLoadException(errorMessage, null);
var callThrowExpr = Expression.Constant(throwAction, typeof(Action));
var defaultExpr = Expression.Default(returnType);
var block = Expression.Block(returnType, Expression.Invoke(callThrowExpr), defaultExpr);
var lambda = Expression.Lambda(delegateType, block, parameters);
return(lambda.Compile());
}
var method = typeof(CurrentFramework).GetTypeInfo().GetMethod(nameof(CurrentFramework.GetDelegateForFunctionPointer)).MakeGenericMethod(delegateType);
return(method.Invoke(null, new object[] { procAddress }));
}