utils/LocIpc.h

/* Copyright (c) 2017 The Linux Foundation. All rights reserved.
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#ifndef __LOC_SOCKET__
#define __LOC_SOCKET__

#include <string>
#include <memory>
#include <LocThread.h>

namespace loc_util {

class LocIpc {
public:
    inline LocIpc() : mIpcFd(-1), mStopRequested(false), mRunnable(nullptr) {}
    inline virtual ~LocIpc() { stopListening(); }

    // Listen for new messages in current thread. Calling this funciton will
    // block current thread. The listening can be stopped by calling stopListening().
    //
    // Argument name is the path of the unix local socket to be listened.
    // The function will return true on success, and false on failure.
    bool startListeningBlocking(const std::string& name);

    // Create a new LocThread and listen for new messages in it.
    // Calling this function will return immediately and won't block current thread.
    // The listening can be stopped by calling stopListening().
    //
    // Argument name is the path of the unix local socket to be be listened.
    // The function will return true on success, and false on failure.
    bool startListeningNonBlocking(const std::string& name);

    // Stop listening to new messages.
    void stopListening();

    // Callback function for receiving incoming messages.
    // Override this function in your derived class to process incoming messages.
    // For each received message, this callback function will be called once.
    // This callback function will be called in the calling thread of startListeningBlocking
    // or in the new LocThread created by startListeningNonBlocking.
    //
    // Argument data contains the received message. You need to parse it.
    virtual void onReceive(const std::string& /*data*/) {}

    // Send out a message.
    // Call this function to send a message in argument data to socket in argument name.
    //
    // Argument name contains the name of the target unix socket. data contains the
    // message to be sent out. Convert your message to a string before calling this function.
    // The function will return true on success, and false on failure.
    static bool send(const char name[], const std::string& data);

private:
    int mIpcFd;
    bool mStopRequested;
    LocThread mThread;
    std::unique_ptr<LocRunnable> mRunnable;
};

}

#endif //__LOC_SOCKET__