1 // 2 // Copyright (C) 2010 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #ifndef UPDATE_ENGINE_COMMON_PROXY_RESOLVER_H_ 18 #define UPDATE_ENGINE_COMMON_PROXY_RESOLVER_H_ 19 20 #include <deque> 21 #include <string> 22 23 #include <base/logging.h> 24 #include <brillo/message_loops/message_loop.h> 25 26 #include "update_engine/common/utils.h" 27 28 namespace chromeos_update_engine { 29 30 extern const char kNoProxy[]; 31 32 // Callback for a call to GetProxiesForUrl(). 33 // Resultant proxies are in |out_proxy|. Each will be in one of the 34 // following forms: 35 // http://<host>[:<port>] - HTTP proxy 36 // socks{4,5}://<host>[:<port>] - SOCKS4/5 proxy 37 // kNoProxy - no proxy 38 typedef base::Callback<void(const std::deque<std::string>& proxies)> 39 ProxiesResolvedFn; 40 41 // An id that identifies a proxy request. Used to cancel an ongoing request 42 // before the callback is called. 43 typedef brillo::MessageLoop::TaskId ProxyRequestId; 44 45 // A constant identifying an invalid ProxyRequestId. 46 extern const ProxyRequestId kProxyRequestIdNull; 47 48 class ProxyResolver { 49 public: ProxyResolver()50 ProxyResolver() {} ~ProxyResolver()51 virtual ~ProxyResolver() {} 52 53 // Finds proxies for the given URL and returns them via the callback. 54 // Returns the id of the pending request on success or kProxyRequestIdNull 55 // otherwise. 56 virtual ProxyRequestId GetProxiesForUrl( 57 const std::string& url, const ProxiesResolvedFn& callback) = 0; 58 59 // Cancel the proxy resolution request initiated by GetProxiesForUrl(). The 60 // |request| value must be the one provided by GetProxiesForUrl(). 61 virtual bool CancelProxyRequest(ProxyRequestId request) = 0; 62 63 private: 64 DISALLOW_COPY_AND_ASSIGN(ProxyResolver); 65 }; 66 67 // Always says to not use a proxy 68 class DirectProxyResolver : public ProxyResolver { 69 public: 70 DirectProxyResolver() = default; 71 ~DirectProxyResolver() override; 72 ProxyRequestId GetProxiesForUrl(const std::string& url, 73 const ProxiesResolvedFn& callback) override; 74 bool CancelProxyRequest(ProxyRequestId request) override; 75 76 // Set the number of direct (non-) proxies to be returned by resolver. 77 // The default value is 1; higher numbers are currently used in testing. set_num_proxies(size_t num_proxies)78 inline void set_num_proxies(size_t num_proxies) { 79 num_proxies_ = num_proxies; 80 } 81 82 private: 83 // The ID of the main loop callback. 84 brillo::MessageLoop::TaskId idle_callback_id_{ 85 brillo::MessageLoop::kTaskIdNull}; 86 87 // Number of direct proxies to return on resolved list; currently used for 88 // testing. 89 size_t num_proxies_{1}; 90 91 // The MainLoop callback, from here we return to the client. 92 void ReturnCallback(const ProxiesResolvedFn& callback); 93 DISALLOW_COPY_AND_ASSIGN(DirectProxyResolver); 94 }; 95 96 } // namespace chromeos_update_engine 97 98 #endif // UPDATE_ENGINE_COMMON_PROXY_RESOLVER_H_ 99