/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef __nsInterfaceRequestorUtils_h

#define __nsInterfaceRequestorUtils_h

#include "nsCOMPtr.h"

// a type-safe shortcut for calling the |GetInterface()| member function

// T must inherit from nsIInterfaceRequestor, but the cast may be ambiguous.

template<class T, class DestinationType>

inline nsresult

CallGetInterface(T* aSource, DestinationType** aDestination)

{

  MOZ_ASSERT(aSource, "null parameter");

  MOZ_ASSERT(aDestination, "null parameter");

  return aSource->GetInterface(NS_GET_TEMPLATE_IID(DestinationType),

                               reinterpret_cast<void**>(aDestination));

}

Unexecuted instantiation: nsresult CallGetInterface<nsIInterfaceRequestor, nsIAuthPrompt2>(nsIInterfaceRequestor*, nsIAuthPrompt2**)

Unexecuted instantiation: nsresult CallGetInterface<nsDocLoader, mozIDOMWindowProxy>(nsDocLoader*, mozIDOMWindowProxy**)

Unexecuted instantiation: nsresult CallGetInterface<nsDocShell, nsIPrompt>(nsDocShell*, nsIPrompt**)

Unexecuted instantiation: nsresult CallGetInterface<nsDocShell, mozIDOMWindowProxy>(nsDocShell*, mozIDOMWindowProxy**)

Unexecuted instantiation: nsresult CallGetInterface<nsIInterfaceRequestor, nsIWebBrowserChrome>(nsIInterfaceRequestor*, nsIWebBrowserChrome**)

Unexecuted instantiation: nsresult CallGetInterface<nsIInterfaceRequestor, nsITestService>(nsIInterfaceRequestor*, nsITestService**)

class MOZ_STACK_CLASS nsGetInterface final : public nsCOMPtr_helper

{

public:

  nsGetInterface(nsISupports* aSource, nsresult* aError)

    : mSource(aSource)

    , mErrorPtr(aError)

  {

  }

  virtual nsresult NS_FASTCALL operator()(const nsIID&, void**) const

    override;

private:

  nsISupports* MOZ_NON_OWNING_REF mSource;

  nsresult* mErrorPtr;

};

inline const nsGetInterface

do_GetInterface(nsISupports* aSource, nsresult* aError = 0)

{

  return nsGetInterface(aSource, aError);

}

#endif // __nsInterfaceRequestorUtils_h