Componentize proxy code from chrome/browser/net

chrome/browser/net/pref_proxy_config_tracker_impl.h

-// Copyright (c) 2012 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 CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_
-#define CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_
-
-#include "base/basictypes.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/observer_list.h"
-#include "base/prefs/pref_change_registrar.h"
-#include "chrome/browser/net/pref_proxy_config_tracker.h"
-#include "components/proxy_config/proxy_config_dictionary.h"
-#include "net/proxy/proxy_config.h"
-#include "net/proxy/proxy_config_service.h"
-
-class PrefService;
-class PrefRegistrySimple;
-
-namespace user_prefs {
-class PrefRegistrySyncable;
-}
-
-// A net::ProxyConfigService implementation that applies preference proxy
-// settings (pushed from PrefProxyConfigTrackerImpl) as overrides to the proxy
-// configuration determined by a baseline delegate ProxyConfigService on
-// non-ChromeOS platforms. ChromeOS has its own implementation of overrides in
-// chromeos::ProxyConfigServiceImpl.
-class ChromeProxyConfigService
-    : public net::ProxyConfigService,
-      public net::ProxyConfigService::Observer {
- public:
-  // Takes ownership of the passed |base_service|.
-  // GetLatestProxyConfig returns ConfigAvailability::CONFIG_PENDING until
-  // UpdateProxyConfig has been called.
-  explicit ChromeProxyConfigService(net::ProxyConfigService* base_service);
-  ~ChromeProxyConfigService() override;
-
-  // ProxyConfigService implementation:
-  void AddObserver(net::ProxyConfigService::Observer* observer) override;
-  void RemoveObserver(net::ProxyConfigService::Observer* observer) override;
-  ConfigAvailability GetLatestProxyConfig(net::ProxyConfig* config) override;
-  void OnLazyPoll() override;
-
-  // Method on IO thread that receives the preference proxy settings pushed from
-  // PrefProxyConfigTrackerImpl.
-  void UpdateProxyConfig(ProxyPrefs::ConfigState config_state,
-                         const net::ProxyConfig& config);
-
- private:
-  // ProxyConfigService::Observer implementation:
-  void OnProxyConfigChanged(const net::ProxyConfig& config,
-                            ConfigAvailability availability) override;
-
-  // Makes sure that the observer registration with the base service is set up.
-  void RegisterObserver();
-
-  scoped_ptr<net::ProxyConfigService> base_service_;
-  base::ObserverList<net::ProxyConfigService::Observer, true> observers_;
-
-  // Tracks configuration state of |pref_config_|. |pref_config_| is valid only
-  // if |pref_config_state_| is not CONFIG_UNSET.
-  ProxyPrefs::ConfigState pref_config_state_;
-
-  // Configuration as defined by prefs.
-  net::ProxyConfig pref_config_;
-
-  // Flag that indicates that a PrefProxyConfigTracker needs to inform us
-  // about a proxy configuration before we may return any configuration.
-  bool pref_config_read_pending_;
-
-  // Indicates whether the base service registration is done.
-  bool registered_observer_;
-
-  DISALLOW_COPY_AND_ASSIGN(ChromeProxyConfigService);
-};
-
-// A class that tracks proxy preferences. It translates the configuration
-// to net::ProxyConfig and pushes the result over to the IO thread for
-// ChromeProxyConfigService::UpdateProxyConfig to use.
-class PrefProxyConfigTrackerImpl : public PrefProxyConfigTracker {
- public:
-  explicit PrefProxyConfigTrackerImpl(PrefService* pref_service);
-  ~PrefProxyConfigTrackerImpl() override;
-
-  // PrefProxyConfigTracker implementation:
-  scoped_ptr<net::ProxyConfigService> CreateTrackingProxyConfigService(
-      scoped_ptr<net::ProxyConfigService> base_service) override;
-
-  // Notifies the tracker that the pref service passed upon construction is
-  // about to go away. This must be called from the UI thread.
-  void DetachFromPrefService() override;
-
-  // Determines if |config_state| takes precedence regardless, which happens if
-  // config is from policy or extension or other-precede.
-  static bool PrefPrecedes(ProxyPrefs::ConfigState config_state);
-
-  // Determines the proxy configuration that should take effect in the network
-  // layer, based on prefs and system configurations.
-  // |pref_state| refers to state of |pref_config|.
-  // |system_availability| refers to availability of |system_config|.
-  // |ignore_fallback_config| indicates if fallback config from prefs should
-  // be ignored.
-  // Returns effective |effective_config| and its state in
-  // |effective_config_source|.
-  static net::ProxyConfigService::ConfigAvailability GetEffectiveProxyConfig(
-      ProxyPrefs::ConfigState pref_state,
-      const net::ProxyConfig& pref_config,
-      net::ProxyConfigService::ConfigAvailability system_availability,
-      const net::ProxyConfig& system_config,
-      bool ignore_fallback_config,
-      ProxyPrefs::ConfigState* effective_config_state,
-      net::ProxyConfig* effective_config);
-
-  // Converts a ProxyConfigDictionary to net::ProxyConfig representation.
-  // Returns true if the data from in the dictionary is valid, false otherwise.
-  static bool PrefConfigToNetConfig(const ProxyConfigDictionary& proxy_dict,
-                                    net::ProxyConfig* config);
-
-  // Registers the proxy preferences. These are actually registered
-  // the same way in local state and in user prefs.
-  static void RegisterPrefs(PrefRegistrySimple* registry);
-  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
-
-  // Creates a proxy configuration from proxy-related preferences of
-  // |pref_service|. Configuration is stored in |config|, return value indicates
-  // whether the configuration is valid.
-  static ProxyPrefs::ConfigState ReadPrefConfig(const PrefService* pref_service,
-                                                net::ProxyConfig* config);
-
- protected:
-  // Get the proxy configuration currently defined by preferences.
-  // Status is indicated in the return value.
-  // Writes the configuration to |config| unless the return value is
-  // CONFIG_UNSET, in which case |config| and |config_source| are not touched.
-  ProxyPrefs::ConfigState GetProxyConfig(net::ProxyConfig* config);
-
-  // Called when there's a change in prefs proxy config.
-  // Subclasses can extend it for changes in other sources of proxy config.
-  virtual void OnProxyConfigChanged(ProxyPrefs::ConfigState config_state,
-                                    const net::ProxyConfig& config);
-
-  void OnProxyPrefChanged();
-
-  const PrefService* prefs() const { return pref_service_; }
-  bool update_pending() const { return update_pending_; }
-
- private:
-  // Tracks configuration state. |pref_config_| is valid only if |config_state_|
-  // is not CONFIG_UNSET.
-  ProxyPrefs::ConfigState config_state_;
-
-  // Configuration as defined by prefs.
-  net::ProxyConfig pref_config_;
-
-  PrefService* pref_service_;
-  ChromeProxyConfigService* chrome_proxy_config_service_;  // Weak ptr.
-  bool update_pending_;  // True if config has not been pushed to network stack.
-  PrefChangeRegistrar proxy_prefs_;
-
-  DISALLOW_COPY_AND_ASSIGN(PrefProxyConfigTrackerImpl);
-};
-
-#endif  // CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_