/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=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 mozilla_net_AutoClose_h #define mozilla_net_AutoClose_h #include "nsCOMPtr.h" #include "mozilla/Mutex.h" namespace mozilla { namespace net { // Like an nsAutoPtr for XPCOM streams (e.g. nsIAsyncInputStream) and other // refcounted classes that need to have the Close() method called explicitly // before they are destroyed. template <typename T> class AutoClose { public: AutoClose() : mMutex("net::AutoClose.mMutex") { } ~AutoClose(){ CloseAndRelease(); } explicit operator bool() { MutexAutoLock lock(mMutex); return mPtr; } already_AddRefed<T> forget() { MutexAutoLock lock(mMutex); return mPtr.forget(); } void takeOver(nsCOMPtr<T> & rhs) { already_AddRefed<T> other = rhs.forget(); TakeOverInternal(&other); } void CloseAndRelease() { TakeOverInternal(nullptr); } private: void TakeOverInternal(already_AddRefed<T> *aOther) { nsCOMPtr<T> ptr; { MutexAutoLock lock(mMutex); ptr.swap(mPtr); if (aOther) { mPtr = *aOther; } } if (ptr) { ptr->Close(); } } void operator=(const AutoClose<T> &) = delete; AutoClose(const AutoClose<T> &) = delete; nsCOMPtr<T> mPtr; Mutex mMutex; }; } // namespace net } // namespace mozilla #endif // mozilla_net_AutoClose_h