// Copyright 2016 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef MOJO_CORE_WATCHER_SET_H_ #define MOJO_CORE_WATCHER_SET_H_ #include "base/containers/flat_map.h" #include "base/memory/raw_ptr.h" #include "base/memory/ref_counted.h" #include "mojo/core/handle_signals_state.h" #include "mojo/core/watcher_dispatcher.h" #include "third_party/abseil-cpp/absl/types/optional.h" namespace mojo { namespace core { // A WatcherSet maintains a set of references to WatcherDispatchers to be // notified when a handle changes state. // // Dispatchers which may be watched by a watcher should own a WatcherSet and // notify it of all relevant state changes. class WatcherSet { public: // |owner| is the Dispatcher who owns this WatcherSet. explicit WatcherSet(Dispatcher* owner); WatcherSet(const WatcherSet&) = delete; WatcherSet& operator=(const WatcherSet&) = delete; ~WatcherSet(); // Notifies all watchers of the handle's current signals state. void NotifyState(const HandleSignalsState& state); // Notifies all watchers that this handle has been closed. void NotifyClosed(); // Adds a new watcher+context. MojoResult Add(const scoped_refptr& watcher, uintptr_t context, const HandleSignalsState& current_state); // Removes a watcher+context. MojoResult Remove(WatcherDispatcher* watcher, uintptr_t context); private: using ContextSet = std::set; struct Entry { Entry(const scoped_refptr& dispatcher); Entry(const Entry&) = delete; Entry& operator=(const Entry&) = delete; Entry(Entry&& other); ~Entry(); Entry& operator=(Entry&& other); scoped_refptr dispatcher; ContextSet contexts; }; const raw_ptr owner_; base::flat_map watchers_; absl::optional last_known_state_; }; } // namespace core } // namespace mojo #endif // MOJO_CORE_WATCHER_SET_H_