trComm *commNewAndConnect(char *hostname, char *port, int connectTimeout){
int fd;
struct addrinfo hints;
struct addrinfo *result, *rp;
int s;
int rc;
int status=1;
//
// The following code is an adaptation from the example in man getaddrinfo
//
// Obtain address(es) matching host/port
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC; /* Allow IPv4 or IPv6 */
hints.ai_socktype = SOCK_STREAM; /* Stream socket */
hints.ai_flags = 0;
hints.ai_protocol = 0; /* Any protocol */
s = getaddrinfo(hostname, port, &hints, &result);
if (s != 0) {
ERROR_AT_LINE(EXIT_FAILURE, errno, __FILE__, __LINE__,
"getaddrinfo on hostname \"%s\": %s\n", hostname, gai_strerror(s));
}
// getaddrinfo() returns a list of address structures.
// Try each address until we successfully connect(2).
// If socket(2) (or connect(2)) fails, we (close the socket
// and) try the next address. */
for (rp = result; rp != NULL; rp = rp->ai_next) {
fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
if (fd == -1)
continue;
rc = connectWithTimeout(fd , rp->ai_addr, rp->ai_addrlen, connectTimeout);
if (rc > 0)
break; /* Success */
if (close(fd) < 0)
ERROR_AT_LINE(EXIT_FAILURE, errno, __FILE__, __LINE__, "close");
}
freeaddrinfo(result); /* No longer needed */
if (rp == NULL) { /* No address succeeded */
return NULL;
}
// We set TCP_NODELAY flag so that packets sent on this TCP connection
// will not be delayed by the system layer
if (setsockopt(fd,IPPROTO_TCP, TCP_NODELAY, &status,sizeof(status)) < 0){
//free(aComm);
ERROR_AT_LINE(EXIT_FAILURE, errno, __FILE__, __LINE__, "setsockopt");
}
// Everything went fine: we can return a communication handle.
return commAlloc(fd);
}
/**
* @brief Destructor.
* Stop serving images and destroy this class.
*/
PCVideoServer::~PCVideoServer()
{
// Stop the images to PC server.
Stop();
// Clear the error so that you can use this object to make a connection to
// the VIDEO_TO_PC_PORT to stop the ImageToPCServer if it is waiting to
// accept connections from a PC.
ClearError();
// Open a socket.
int camSock = socket(AF_INET, SOCK_STREAM, 0);
if (camSock == ERROR)
{
wpi_setErrnoError();
return;
}
ScopedSocket scopedCamSock(camSock);
// If successful
if (!StatusIsFatal())
{
// Create a connection to the localhost.
struct sockaddr_in selfAddr;
int sockAddrSize = sizeof(selfAddr);
bzero ((char *) &selfAddr, sockAddrSize);
selfAddr.sin_family = AF_INET;
#if defined(__FreeBSD__) || defined(NETBSD)
selfAddr.sin_len = (u_char) sockAddrSize;
#endif
selfAddr.sin_port = htons (VIDEO_TO_PC_PORT);
if (( (int)(selfAddr.sin_addr.s_addr = inet_addr (const_cast<char*>("localhost")) ) != ERROR) ||
( (int)(selfAddr.sin_addr.s_addr = hostGetByName (const_cast<char*>("localhost")) ) != ERROR))
{
struct timeval connectTimeout;
connectTimeout.tv_sec = 1;
connectTimeout.tv_usec = 0;
connectWithTimeout(camSock, (struct sockaddr *) &selfAddr, sockAddrSize, &connectTimeout);
}
}
}