blob: 25ab6ef57f714830dece737932e05a2d7be48be2 [file] [log] [blame]
// Copyright 2014 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 COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_LOG_ROUTER_H_
#define COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_LOG_ROUTER_H_
#include <set>
#include <string>
#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/observer_list.h"
namespace password_manager {
class LogManager;
class LogReceiver;
// The router stands between LogManager and LogReceiver instances. Both managers
// and receivers need to register (and unregister) with the router. After that,
// the following communication is enabled:
// * LogManagers are notified when logging starts or stops being possible
// * LogReceivers are sent logs routed through LogRouter
class LogRouter {
public:
LogRouter();
~LogRouter();
// Passes logs to the router. Only call when there are receivers registered.
void ProcessLog(const std::string& text);
// All four (Unr|R)egister* methods below are safe to call from the
// constructor of the registered object, because they do not call that object,
// and the router only runs on a single thread.
// The managers must register to be notified about whether there are some
// receivers or not. RegisterManager adds |manager| to the right observer list
// and returns true iff there are some receivers registered.
bool RegisterManager(LogManager* manager);
// Remove |manager| from the observers list.
void UnregisterManager(LogManager* manager);
// The receivers must register to get updates with new logs in the future.
// RegisterReceiver adds |receiver| to the right observer list, and returns
// the logs accumulated so far. (It returns by value, not const ref, to
// provide a snapshot as opposed to a link to |accumulated_logs_|.)
std::string RegisterReceiver(LogReceiver* receiver) WARN_UNUSED_RESULT;
// Remove |receiver| from the observers list.
void UnregisterReceiver(LogReceiver* receiver);
private:
// Observer lists for managers and receivers. The |true| in the template
// specialisation means that they will check that all observers were removed
// on destruction.
base::ObserverList<LogManager, true>::Unchecked managers_;
base::ObserverList<LogReceiver, true>::Unchecked receivers_;
// Logs accumulated since the first receiver was registered.
std::string accumulated_logs_;
DISALLOW_COPY_AND_ASSIGN(LogRouter);
};
} // namespace password_manager
#endif // COMPONENTS_PASSWORD_MANAGER_CORE_BROWSER_LOG_ROUTER_H_