1 /*
2  * Copyright 2018, 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 #pragma once
18 
19 #include "interface_state.h"
20 #include "pollable.h"
21 #include "result.h"
22 
23 #include <unordered_set>
24 
25 /** Monitor network interfaces and provide notifications of changes to those
26  *  interfaces.
27  */
28 class Monitor : public Pollable {
29 public:
30     using OnInterfaceStateCallback = std::function<void (unsigned int index,
31                                                          const char* name,
32                                                          InterfaceState state)>;
33     Monitor();
34     ~Monitor();
35 
36     Result init();
37 
38     void setOnInterfaceState(OnInterfaceStateCallback callback);
39 
40     // Pollable interface
41     void getPollData(std::vector<pollfd>* fds) const override;
42     Timestamp getTimeout() const override;
43     bool onReadAvailable(int fd, int* status) override;
44     bool onClose(int fd, int* status) override;
45     bool onTimeout(int* status) override;
46 
47 private:
48     Result openSocket();
49     Result requestInterfaces();
50     void closeSocket();
51     void handleNewLink(const struct nlmsghdr* hdr);
52 
53     int mSocketFd;
54     OnInterfaceStateCallback mOnInterfaceStateCallback;
55     std::unordered_set<unsigned int> mUpInterfaces;
56 };
57 
58