TCPServerBase.h

#ifndef _ots_TCPServerBase_h_
#define _ots_TCPServerBase_h_
 
#include <future>
#include <map>
#include <mutex>
#include <string>
#include <vector>
// #include <thread>
#include <atomic>
#include "otsdaq/NetworkUtilities/TCPSocket.h"
 
namespace ots
{
class TCPServerBase : public virtual TCPSocket
{
  public:
    TCPServerBase(
        unsigned int serverPort,
        unsigned int maxNumberOfClients = 0);  
    virtual ~TCPServerBase(void);
 
    void startAccept(void);
    void shutdownAccept(void);
    void broadcastPacket(const char* message, std::size_t length);
    void broadcastPacket(const std::string& message);
    void broadcast(const char* message, std::size_t length);
    void broadcast(const std::string& message);
    void broadcast(const std::vector<char>& message);
    void broadcast(const std::vector<uint16_t>& message);
 
  protected:
    virtual void acceptConnections() = 0;
 
    void closeClientSocket(int socket);
    template<class T>
    T* acceptClient(bool blocking = true)
    {
        int                         socketId = accept(blocking);
        std::lock_guard<std::mutex> lock(fClientsMutex);
        fConnectedClients.emplace(socketId, new T(socketId));
        return dynamic_cast<T*>(fConnectedClients[socketId]);
    }
 
    void removeClient(int socketId);
    std::vector<int> getClientSocketIds(void) const;
 
    void pingActiveClients(void);
 
    // std::promise<bool>        fAcceptPromise;
    // fClientsMutex guards fConnectedClients. Every method that reads or modifies
    // the map takes it (accept, broadcast, ping, close, remove, receive).
    mutable std::mutex               fClientsMutex;
    std::map<int, TCPSocket*>        fConnectedClients;
    std::map<int, std::future<void>> fConnectedClientsFuture;
    const int                        E_SHUTDOWN = 0;
    bool                             getAccept() { return fAccept.load(); }
 
  private:
    void closeClientSockets(
        void);  
    int accept(bool blocking = true);
 
    const int        fMaxConnectionBacklog = 5;
    unsigned int     fMaxNumberOfClients;
    unsigned int     fServerPort;
    std::atomic_bool fAccept;
    //  std::thread       fAcceptThread;
    std::future<void> fAcceptFuture;
};
}  // namespace ots
 
#endif