public IntPtr ContextData; // ThunkContextData pointer which will be stored in the context slot of the thunk
public PInvokeDelegateThunk(Delegate del)
{
Thunk = RuntimeAugments.AllocateThunk(s_thunkPoolHeap);
Debug.Assert(Thunk != IntPtr.Zero);
if (Thunk == IntPtr.Zero)
{
// We've either run out of memory, or failed to allocate a new thunk due to some other bug. Now we should fail fast
Environment.FailFast("Insufficient number of thunks.");
}
else
{
//
// Allocate unmanaged memory for GCHandle of delegate and function pointer of open static delegate
// We will store this pointer on the context slot of thunk data
//
ContextData = AllocHGlobal(2 * IntPtr.Size);
unsafe
{
ThunkContextData *thunkData = (ThunkContextData *)ContextData;
// allocate a weak GChandle for the delegate
thunkData->Handle = GCHandle.Alloc(del, GCHandleType.Weak);
// if it is an open static delegate get the function pointer
thunkData->FunctionPtr = del.GetRawFunctionPointerForOpenStaticDelegate();
}
}
}
private static IntPtr AllocateThunk(Delegate del)
{
//TODO: cache del->thunk here
if (s_thunkPoolHeap == null)
{
s_thunkPoolHeap = RuntimeAugments.CreateThunksHeap(RuntimeImports.GetInteropCommonStubAddress());
Debug.Assert(s_thunkPoolHeap != null);
}
IntPtr pThunk = RuntimeAugments.AllocateThunk(s_thunkPoolHeap);
Debug.Assert(pThunk != IntPtr.Zero);
if (pThunk == IntPtr.Zero)
{
// We've either run out of memory, or failed to allocate a new thunk due to some other bug. Now we should fail fast
Environment.FailFast("Insufficient number of thunks.");
return(IntPtr.Zero);
}
else
{
McgPInvokeDelegateData pinvokeDelegateData;
if (!RuntimeAugments.InteropCallbacks.TryGetMarshallerDataForDelegate(del.GetTypeHandle(), out pinvokeDelegateData))
{
Environment.FailFast("Couldn't find marshalling stubs for delegate.");
}
IntPtr pContext;
unsafe
{
//
// Allocate unmanaged memory for GCHandle of delegate and function pointer of open static delegate
// We will store this pointer on the context slot of thunk data
//
pContext = (IntPtr)CoTaskMemAllocAndZeroMemory((System.IntPtr)(2 * (IntPtr.Size)));
ThunkContextData *thunkData = (ThunkContextData *)pContext;
(*thunkData).Handle = GCHandle.Alloc(del, GCHandleType.Weak);
(*thunkData).FunctionPtr = del.GetRawFunctionPointerForOpenStaticDelegate();
}
//
// For open static delegates set target to ReverseOpenStaticDelegateStub which calls the static function pointer directly
//
IntPtr pTarget = del.GetRawFunctionPointerForOpenStaticDelegate() == IntPtr.Zero ? pinvokeDelegateData.ReverseStub : pinvokeDelegateData.ReverseOpenStaticDelegateStub;
RuntimeAugments.SetThunkData(s_thunkPoolHeap, pThunk, pContext, pTarget);
return(pThunk);
}
}
