1 /*
2  *  Copyright 2015 The WebRTC Project Authors. All rights reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef RTC_BASE_NETWORKMONITOR_H_
12 #define RTC_BASE_NETWORKMONITOR_H_
13 
14 #include "rtc_base/logging.h"
15 #include "rtc_base/network_constants.h"
16 #include "rtc_base/sigslot.h"
17 #include "rtc_base/thread.h"
18 
19 namespace rtc {
20 
21 class IPAddress;
22 
23 enum class NetworkBindingResult {
24   SUCCESS = 0,   // No error
25   FAILURE = -1,  // Generic error
26   NOT_IMPLEMENTED = -2,
27   ADDRESS_NOT_FOUND = -3,
28   NETWORK_CHANGED = -4
29 };
30 
31 class NetworkBinderInterface {
32  public:
33   // Binds a socket to the network that is attached to |address| so that all
34   // packets on the socket |socket_fd| will be sent via that network.
35   // This is needed because some operating systems (like Android) require a
36   // special bind call to put packets on a non-default network interface.
37   virtual NetworkBindingResult BindSocketToNetwork(
38       int socket_fd,
39       const IPAddress& address) = 0;
~NetworkBinderInterface()40   virtual ~NetworkBinderInterface() {}
41 };
42 
43 /*
44  * Receives network-change events via |OnNetworksChanged| and signals the
45  * networks changed event.
46  *
47  * Threading consideration:
48  * It is expected that all upstream operations (from native to Java) are
49  * performed from the worker thread. This includes creating, starting and
50  * stopping the monitor. This avoids the potential race condition when creating
51  * the singleton Java NetworkMonitor class. Downstream operations can be from
52  * any thread, but this class will forward all the downstream operations onto
53  * the worker thread.
54  *
55  * Memory consideration:
56  * NetworkMonitor is owned by the caller (NetworkManager). The global network
57  * monitor factory is owned by the factory itself but needs to be released from
58  * the factory creator.
59  */
60 // Generic network monitor interface. It starts and stops monitoring network
61 // changes, and fires the SignalNetworksChanged event when networks change.
62 class NetworkMonitorInterface {
63  public:
64   NetworkMonitorInterface();
65   virtual ~NetworkMonitorInterface();
66 
67   sigslot::signal0<> SignalNetworksChanged;
68 
69   virtual void Start() = 0;
70   virtual void Stop() = 0;
71 
72   // Implementations should call this method on the base when networks change,
73   // and the base will fire SignalNetworksChanged on the right thread.
74   virtual void OnNetworksChanged() = 0;
75 
76   virtual AdapterType GetAdapterType(const std::string& interface_name) = 0;
77 };
78 
79 class NetworkMonitorBase : public NetworkMonitorInterface,
80                            public MessageHandler,
81                            public sigslot::has_slots<> {
82  public:
83   NetworkMonitorBase();
84   ~NetworkMonitorBase() override;
85 
86   void OnNetworksChanged() override;
87 
88   void OnMessage(Message* msg) override;
89 
90  protected:
worker_thread()91   Thread* worker_thread() { return worker_thread_; }
92 
93  private:
94   Thread* worker_thread_;
95 };
96 
97 /*
98  * NetworkMonitorFactory creates NetworkMonitors.
99  */
100 class NetworkMonitorFactory {
101  public:
102   // This is not thread-safe; it should be called once (or once per audio/video
103   // call) during the call initialization.
104   static void SetFactory(NetworkMonitorFactory* factory);
105 
106   static void ReleaseFactory(NetworkMonitorFactory* factory);
107   static NetworkMonitorFactory* GetFactory();
108 
109   virtual NetworkMonitorInterface* CreateNetworkMonitor() = 0;
110 
111   virtual ~NetworkMonitorFactory();
112 
113  protected:
114   NetworkMonitorFactory();
115 };
116 
117 }  // namespace rtc
118 
119 #endif  // RTC_BASE_NETWORKMONITOR_H_
120