Re: [PATCH v2 3/8] dllhost: Implement ISurrogate::LoadDllServer().

[Huw Davies]

On Tue, Feb 22, 2022 at 05:50:02PM +0300, Dmitry Timoshkov wrote:
> v2: Fixed a few -Wformat warnings.
> Signed-off-by: Dmitry Timoshkov
>
> programs/dllhost/dllhost.c | 217 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 213 insertions(+), 4 deletions(-)
>
> diff --git a/programs/dllhost/dllhost.c b/programs/dllhost/dllhost.c
> index ac1cf0e3d33..5c0a93c9a71 100644
> --- a/programs/dllhost/dllhost.c
> +++ b/programs/dllhost/dllhost.c
> @@ -28,9 +28,193 @@
> +static HRESULT WINAPI factory_QueryInterface(IClassFactory *iface,
> - REFIID iid, void **ppv)
>
> +{
> - struct factory *factory = impl_from_IClassFactory(iface);
> -
> - TRACE("(%p,%s,%p)\n", iface, wine_dbgstr_guid(iid), ppv);
> -
> - if (!ppv) return E_INVALIDARG;
> -
> - if (IsEqualIID(iid, &IID_IUnknown) ||
> -
>    IsEqualIID(iid, &IID_IClassFactory))
> - {
> -
>    IClassFactory_AddRef(&factory->IClassFactory_iface);
> -
>    *ppv = &factory->IClassFactory_iface;
> -
>    return S_OK;
> - }
> - else if (IsEqualIID(iid, &IID_IMarshal))
> - {
> -
>    IClassFactory_AddRef(&factory->IClassFactory_iface);
> -
>    *ppv = &factory->IMarshal_iface;
> -
>    return S_OK;
> - }
> -
> - *ppv = NULL;
> - return E_NOINTERFACE;
>
> +}

[snip]
> +static HRESULT WINAPI marshal_QueryInterface(IMarshal *iface, REFIID iid, LPVOID *ppv)
> +{
> - struct factory *factory = impl_from_IMarshal(iface);
> -
> - TRACE("(%p,%s,%p)\n", iface, wine_dbgstr_guid(iid), ppv);
> -
> - if (!ppv) return E_INVALIDARG;
> -
> - if (IsEqualIID(iid, &IID_IUnknown) ||
> -
>    IsEqualIID(iid, &IID_IMarshal))
> - {
> -
>    IMarshal_AddRef(&factory->IMarshal_iface);
> -
>    *ppv = &factory->IMarshal_iface;
> -
>    return S_OK;
> - }
> -
> - *ppv = NULL;
> - return E_NOINTERFACE;
>
> +}

These two QI implementations break two of the QI rules:
https://docs.microsoft.com/en-us/windows/win32/com/rules-for-implementing-qu...

There isn't a unique identity and it's not possible to QI
IClassFactory from the IMarshal interface.
> - factory->IClassFactory_iface.lpVtbl = &ClassFactory_Vtbl;
> - factory->IMarshal_iface.lpVtbl = &Marshal_Vtbl;
> - factory->clsid = *clsid;
> - factory->ref = 1;
> -
> - hr = CoRegisterClassObject(clsid, (IUnknown *)&factory->IClassFactory_iface,
> -
>                           CLSCTX_LOCAL_SERVER, REGCLS_SURROGATE, &surrogate->cookie);

Does REGCLS_SURROGATE require any special treatment from combase?

Huw.