1 /*
2  * Copyright (C) 2019 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 <android-base/macros.h>
20 #include <android-base/unique_fd.h>
21 #include <linux/can.h>
22 
23 #include <atomic>
24 #include <chrono>
25 #include <functional>
26 #include <thread>
27 
28 namespace android::hardware::automotive::can::V1_0::implementation {
29 
30 /** Wrapper around SocketCAN socket. */
31 struct CanSocket {
32     using ReadCallback = std::function<void(const struct canfd_frame&, std::chrono::nanoseconds)>;
33     using ErrorCallback = std::function<void(int errnoVal)>;
34 
35     /**
36      * Open and bind SocketCAN socket.
37      *
38      * \param ifname SocketCAN network interface name (such as can0)
39      * \param rdcb Callback on received messages
40      * \param errcb Callback on socket failure
41      * \return Socket instance, or nullptr if it wasn't possible to open one
42      */
43     static std::unique_ptr<CanSocket> open(const std::string& ifname, ReadCallback rdcb,
44                                            ErrorCallback errcb);
45     virtual ~CanSocket();
46 
47     /**
48      * Send CAN frame.
49      *
50      * \param frame Frame to send
51      * \return true in case of success, false otherwise
52      */
53     bool send(const struct canfd_frame& frame);
54 
55   private:
56     CanSocket(base::unique_fd socket, ReadCallback rdcb, ErrorCallback errcb);
57     void readerThread();
58 
59     ReadCallback mReadCallback;
60     ErrorCallback mErrorCallback;
61 
62     const base::unique_fd mSocket;
63     std::thread mReaderThread;
64     std::atomic<bool> mStopReaderThread = false;
65     std::atomic<bool> mReaderThreadFinished = false;
66 
67     DISALLOW_COPY_AND_ASSIGN(CanSocket);
68 };
69 
70 }  // namespace android::hardware::automotive::can::V1_0::implementation
71