1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_PROXY_PROXY_CONFIG_SERVICE_H_ 6 #define NET_PROXY_PROXY_CONFIG_SERVICE_H_ 7 #pragma once 8 9 #include "net/base/net_export.h" 10 11 namespace net { 12 13 class ProxyConfig; 14 15 // Service for watching when the proxy settings have changed. 16 class NET_EXPORT ProxyConfigService { 17 public: 18 // Indicates whether proxy configuration is valid, and if not, why. 19 enum ConfigAvailability { 20 // Configuration is pending, observers will be notified later. 21 CONFIG_PENDING, 22 // Configuration is present and valid. 23 CONFIG_VALID, 24 // No configuration is set. 25 CONFIG_UNSET 26 }; 27 28 // Observer for being notified when the proxy settings have changed. 29 class NET_EXPORT Observer { 30 public: 31 virtual ~Observer() {} 32 // Notification callback that should be invoked by ProxyConfigService 33 // implementors whenever the configuration changes. |availability| indicates 34 // the new availability status and can be CONFIG_UNSET or CONFIG_VALID (in 35 // which case |config| contains the configuration). Implementors must not 36 // pass CONFIG_PENDING. 37 virtual void OnProxyConfigChanged(const ProxyConfig& config, 38 ConfigAvailability availability) = 0; 39 }; 40 41 virtual ~ProxyConfigService() {} 42 43 // Adds/Removes an observer that will be called whenever the proxy 44 // configuration has changed. 45 virtual void AddObserver(Observer* observer) = 0; 46 virtual void RemoveObserver(Observer* observer) = 0; 47 48 // Gets the most recent availability status. If a configuration is present, 49 // the proxy configuration is written to |config| and CONFIG_VALID is 50 // returned. Returns CONFIG_PENDING if it is not available yet. In this case, 51 // it is guaranteed that subscribed observers will be notified of a change at 52 // some point in the future once the configuration is available. 53 // Note that to avoid re-entrancy problems, implementations should not 54 // dispatch any change notifications from within this function. 55 virtual ConfigAvailability GetLatestProxyConfig(ProxyConfig* config) = 0; 56 57 // ProxyService will call this periodically during periods of activity. 58 // It can be used as a signal for polling-based implementations. 59 // 60 // Note that this is purely used as an optimization -- polling 61 // implementations could simply set a global timer that goes off every 62 // X seconds at which point they check for changes. However that has 63 // the disadvantage of doing continuous work even during idle periods. 64 virtual void OnLazyPoll() {} 65 }; 66 67 } // namespace net 68 69 #endif // NET_PROXY_PROXY_CONFIG_SERVICE_H_ 70
