TCPServerBase.cc

// #ifndef BEAGLEBONE
// #include "otsdaq_cmsburninbox/BeagleBone/BeagleBoneUtils/TCPServerBase.h"
// #else
#include "otsdaq/NetworkUtilities/TCPServerBase.h"
#include "otsdaq/Macros/CoutMacros.h"
#include "otsdaq/NetworkUtilities/TCPTransmitterSocket.h"
 
// #endif
 
#include <arpa/inet.h>
#include <errno.h>   // errno
#include <string.h>  // errno
#include <sys/socket.h>
#include <iostream>
#include <thread>
 
// #include <sys/socket.h>
// #include <netinet/in.h>
// #include <netdb.h>
 
using namespace ots;
 
//==============================================================================
TCPServerBase::TCPServerBase(unsigned int serverPort, unsigned int maxNumberOfClients)
    : fMaxNumberOfClients(maxNumberOfClients), fServerPort(serverPort), fAccept(true)
{
    // 0 or -1 means no restrictions on the number of clients
    if(fMaxNumberOfClients == 0)
        fMaxNumberOfClients = (unsigned)-1;
    // CANNOT GO IN THE CONSTRUCTOR OR IT MIGHT START BEFORE THE CHILD CLASS CONSTRUCTOR IS FULLY CONSTRUCTED
    // THIS MIGHT RESULT IN THE CALL OF THE VIRTUAL TCPServerBase::acceptConnections
    // startAccept();
}
 
//==============================================================================
TCPServerBase::~TCPServerBase(void)
{
    __COUT__ << "Shutting down accept for socket: " << getSocketId() << std::endl;
    shutdownAccept();
    while(fAcceptFuture.valid() && fAcceptFuture.wait_for(std::chrono::milliseconds(
                                       100)) != std::future_status::ready)
    {
        __COUT__ << "Server accept still running" << std::endl;
        shutdownAccept();
    }
    //__COUT__ << "Closing connected client sockets for socket: " << getSocketId() << std::endl;
    closeClientSockets();
    //__COUT__ << "Closed all sockets connected to server: " << getSocketId() << std::endl;
}
 
//==============================================================================
void TCPServerBase::startAccept(void)
{
    struct sockaddr_in checkAddr;
    socklen_t          addrLen = sizeof(checkAddr);
    if(::getsockname(getSocketId(), (struct sockaddr*)&checkAddr, &addrLen) == 0 &&
       checkAddr.sin_port != 0)
    {
        __COUT__ << "Socket " << getSocketId() << " is already bound to port "
                 << ntohs(checkAddr.sin_port) << std::endl;
        return;
    }
 
    //  __COUT__ << "Begin startAccept" << std::endl;
    int opt = 1;  // SO_REUSEADDR - man socket(7)
    if(::setsockopt(getSocketId(), SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(int)) == -1)
    {
        close();
        __SS__ << "Setsockopt: " << strerror(errno) << __E__;
        __SS_THROW__;
    }
 
    struct sockaddr_in serverAddr;
    bzero((char*)&serverAddr, sizeof(serverAddr));
    serverAddr.sin_family      = AF_INET;
    serverAddr.sin_port        = htons(fServerPort);
    serverAddr.sin_addr.s_addr = INADDR_ANY;
 
    if(::bind(getSocketId(), (struct sockaddr*)&serverAddr, sizeof(serverAddr)) != 0)
    {
        close();
        __SS__ << "Bind: " << strerror(errno) << __E__;
        __SS_THROW__;
    }
    // freeaddrinfo(serverAddr); // all done with this structure
 
    if(::listen(getSocketId(), fMaxConnectionBacklog) != 0)
    {
        close();
        __SS__ << "Listen: " << strerror(errno) << __E__;
        __SS_THROW__;
    }
 
    fAccept = true;
    fAcceptFuture =
        std::async(std::launch::async, &TCPServerBase::acceptConnections, this);
    //  __COUT__ << "Done startAccept" << std::endl;
}
 
//==============================================================================
int TCPServerBase::accept(bool blocking)
{
    __COUT__ << "Now server accept connections on socket: " << getSocketId() << std::endl;
    if(getSocketId() == invalidSocketId)
    {
        __SS__ << "Accept called on a bad socket object (this object was moved)" << __E__;
        __SS_THROW__;
    }
 
    struct sockaddr_storage clientAddress;  // connector's address information
    socklen_t               clientAddressSize = sizeof(clientAddress);
    int                     clientSocket      = invalidSocketId;
    if(blocking)
    {
        //__COUT__ << "Number of connected clients: " << fConnectedClients.size() << std::endl;
        // clientSocket = ::accept4(getSocketId(),(struct sockaddr *)&clientAddress,  &clientAddressSize, 0);
        // unsigned counter = 0;
        __COUT__ << "Client list on input:\n";
        for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
        {
            __COUT__ << " --> Client: " << it->first << " : " << it->second << std::endl;
        }
        while(true)
        {
            clientSocket = ::accept(
                getSocketId(), (struct sockaddr*)&clientAddress, &clientAddressSize);
            __COUT__ << ": clientSocket returned = " << clientSocket << std::endl;
 
            //FIXME: Commenting out this line to avoid seg-fault in the case there are two clients connecting from the same process...
            // pingActiveClients();  // This message is to check if there are clients that disconnected and, if so, they are removed from the client list
            if(fAccept && fMaxNumberOfClients > 0 &&
               fConnectedClients.size() >= fMaxNumberOfClients)
            {
                send(clientSocket, "Too many clients connected!", 27, 0);
                ::shutdown(clientSocket, SHUT_WR);
                continue;
            }
            break;
        }
        __COUT__ << "fAccept? " << fAccept << std::endl;
        if(!fAccept)
        {
            throw E_SHUTDOWN;
        }
        else if(clientSocket == invalidSocketId)
        {
            __COUT__ << "New socket invalid?: " << clientSocket << " errno: " << errno
                     << std::endl;
            __SS__ << "Accept: " << strerror(errno) << __E__;
            __SS_THROW__;
        }
 
        __COUT__ << "Server just accepted a connection on socket: " << getSocketId()
                 << " Client socket: " << clientSocket << std::endl;
        return clientSocket;
    }
    else
    {
        constexpr int  sleepMSeconds   = 5;
        constexpr int  timeoutSeconds  = 0;
        constexpr int  timeoutUSeconds = 1000;
        struct timeval timeout;
        timeout.tv_sec  = timeoutSeconds;
        timeout.tv_usec = timeoutUSeconds;
 
        fd_set fdSet;
 
        while(fAccept)
        {
            FD_ZERO(&fdSet);
            FD_SET(getSocketId(), &fdSet);
            select(getSocketId() + 1, &fdSet, 0, 0, &timeout);
 
            if(FD_ISSET(getSocketId(), &fdSet))
            {
                struct sockaddr_in clientAddress;
                socklen_t          socketSize = sizeof(clientAddress);
                // int newSocketFD = ::accept4(fdServerSocket_,(struct sockaddr*)&clientAddress,&socketSize, (pushOnly_ ? SOCK_NONBLOCK : 0));
                clientSocket = ::accept(
                    getSocketId(),
                    (struct sockaddr*)&clientAddress,
                    &socketSize);  // Blocking since select goes in timeout if there is nothing
                if(clientSocket == invalidSocketId)
                {
                    __COUT__ << "New socket invalid?: " << clientSocket
                             << " errno: " << errno << std::endl;
                    __SS__ << "Accept: " << strerror(errno) << __E__;
                    __SS_THROW__;
                }
                return clientSocket;
            }
            std::this_thread::sleep_for(std::chrono::milliseconds(sleepMSeconds));
        }
        throw E_SHUTDOWN;
    }
}
 
//==============================================================================
void TCPServerBase::closeClientSockets(void)
{
    for(auto& socket : fConnectedClients)
    {
        try
        {
            socket.second->sendClose();
        }
        catch(const std::exception& e)
        {
            // I can get here with the TCPPubishServer because it doesn't keep track of the clients that might have already disconnected
            // Just do nothing!
            __COUT__ << e.what() << '\n';
        }
 
        auto clientThread = fConnectedClientsFuture.find(socket.first);
        if(clientThread != fConnectedClientsFuture.end())
            clientThread->second.wait();  // Waiting for client thread
        delete socket.second;
    }
    fConnectedClients.clear();
    fConnectedClientsFuture.clear();
}
 
//==============================================================================
void TCPServerBase::closeClientSocket(int socket)
{
    // This method is called inside the thread itself so it cannot call the removeClientSocketFuture!!!
    auto it = fConnectedClients.find(socket);
    if(it != fConnectedClients.end())
    {
        if(it->second->getSocketId() == socket)
        {
            try
            {
                if(it->second != nullptr)
                    it->second->sendClose();
            }
            catch(const std::exception& e)
            {
                // I can get here with the TCPPubishServer because it doesn't keep track of the clients that might have already disconnected
                // Just do nothing!
                __COUT__ << e.what() << '\n';
            }
            delete it->second;
            fConnectedClients.erase(it);
        }
        else
        {
            __SS__
                << "SocketId in fConnectedClients != socketId in TCPSocket! Impossible!!!"
                << __E__;
            __SS_THROW__;
        }
    }
}
 
//==============================================================================
void TCPServerBase::broadcastPacket(const char* message, std::size_t length)
{
    broadcastPacket(std::string(message, length));
}
 
//==============================================================================
void TCPServerBase::broadcastPacket(const std::string& message)
{
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->sendPacket(message);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "I don't think that this error is possible because I close the socket when I get disconnected...if you see this then you should
            // contact Lorenzo Uplegger" << std::endl;
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            // __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//========================================================================================================================
void TCPServerBase::broadcast(const char* message, std::size_t length)
{
    //  std::lock_guard<std::mutex> lock(clientsMutex_);
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->send(message, length);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "I don't think that this error is possible because I close the socket when I get disconnected...if you see this then you should
            // contact Lorenzo Uplegger" << std::endl;
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            // __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//==============================================================================
void TCPServerBase::broadcast(const std::string& message)
{
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->send(message);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "I don't think that this error is possible because I close the socket when I get disconnected...if you see this then you should
            // contact Lorenzo Uplegger" << std::endl;
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            // __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//==============================================================================
void TCPServerBase::broadcast(const std::vector<char>& message)
{
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->send(message);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "I don't think that this error is possible because I close the socket when I get disconnected...if you see this then you should
            // contact Lorenzo Uplegger" << std::endl;
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            // __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//==============================================================================
void TCPServerBase::broadcast(const std::vector<uint16_t>& message)
{
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->send(message);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
            {
                __COUT__ << "Removing client entry from future connected clients list\n";
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            }
            __COUT__ << "Removing client entry from connected clients list\n";
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//==============================================================================
void TCPServerBase::pingActiveClients()
{
    for(auto it = fConnectedClients.begin(); it != fConnectedClients.end(); it++)
    {
        __COUT__ << "Pinging client " << it->first << " : " << it->second << std::endl;
        try
        {
            if(auto sock = dynamic_cast<TCPTransmitterSocket*>(it->second);
               sock != nullptr)
                sock->send("", 0, true);
        }
        catch(const std::exception& e)
        {
            // __COUT__ << "I don't think that this error is possible because I close the socket when I get disconnected...if you see this then you should
            // contact Lorenzo Uplegger" << std::endl;
            // __COUT__ << "This should only happen with the TCPSubscribeServer because it doesn't keep track of the connected clients..." << std::endl;
            __COUT__ << "Error: " << e.what() << std::endl;
            if(fConnectedClientsFuture.find(it->first) != fConnectedClientsFuture.end())
            {
                __COUT__ << "Removing client entry from future connected clients list\n";
                fConnectedClientsFuture.erase(fConnectedClientsFuture.find(it->first));
            }
            __COUT__ << "Removing client entry from connected clients list\n";
            delete it->second;
            fConnectedClients.erase(it--);
        }
    }
}
 
//==============================================================================
void TCPServerBase::shutdownAccept()
{
    fAccept = false;
    shutdown(getSocketId(), SHUT_RD);
}