diff --git a/src/libguac/tcp.c b/src/libguac/tcp.c index e4ae71f24..03b0d9f58 100644 --- a/src/libguac/tcp.c +++ b/src/libguac/tcp.c @@ -54,8 +54,7 @@ int guac_tcp_connect(const char* hostname, const char* port, const int timeout) } /* Attempt connection to each address until success */ - current_address = addresses; - while (current_address != NULL) { + for (current_address = addresses; current_address != NULL; current_address = current_address->ai_next) { /* Resolve hostname */ if ((retval = getnameinfo(current_address->ai_addr, @@ -69,40 +68,80 @@ int guac_tcp_connect(const char* hostname, const char* port, const int timeout) continue; } - /* Get socket */ + /* Get socket or return the error. */ fd = socket(current_address->ai_family, SOCK_STREAM, 0); if (fd < 0) { freeaddrinfo(addresses); return fd; } - /* Set socket to non-blocking */ - fcntl(fd, F_SETFL, O_NONBLOCK); + /* Variable to store current socket options. */ + int opt; + + /* Get current socket options */ + if ((opt = fcntl(fd, F_GETFL, NULL)) < 0) { + guac_error = GUAC_STATUS_INVALID_ARGUMENT; + guac_error_message = "Failed to retrieve socket options."; + close(fd); + continue; + } - /* Set up timeout. */ - fd_set fdset; - FD_ZERO(&fdset); - FD_SET(fd, &fdset); + /* Set socket to non-blocking */ + if (fcntl(fd, F_SETFL, opt | O_NONBLOCK) < 0) { + guac_error = GUAC_STATUS_INVALID_ARGUMENT; + guac_error_message = "Failed to set non-blocking socket."; + close(fd); + continue; + } + /* Structure that stores our timeout setting. */ struct timeval tv; tv.tv_sec = timeout; tv.tv_usec = 0; /* Connect and wait for timeout */ - if (connect(fd, current_address->ai_addr, current_address->ai_addrlen) < 0) { - guac_error = GUAC_STATUS_REFUSED; - guac_error_message = "Unable to connect via socket."; - close(fd); - break; + if ((retval = connect(fd, current_address->ai_addr, current_address->ai_addrlen)) < 0) { + if (errno == EINPROGRESS) { + /* Set up timeout. */ + fd_set fdset; + FD_ZERO(&fdset); + FD_SET(fd, &fdset); + + retval = select(fd + 1, NULL, &fdset, NULL, &tv); + } + + else { + guac_error = GUAC_STATUS_REFUSED; + guac_error_message = "Unable to connect via socket."; + close(fd); + continue; + } } - /* Check for the connection and break if successful */ - if (select(fd + 1, NULL, &fdset, NULL, &tv) > 0) + /* Successful connection */ + if (retval > 0) { + /* Restore previous socket options. */ + if (fcntl(fd, F_SETFL, opt) < 0) { + guac_error = GUAC_STATUS_INVALID_ARGUMENT; + guac_error_message = "Failed to reset socket options."; + close(fd); + continue; + } + break; + } + + if (retval == 0) { + guac_error = GUAC_STATUS_REFUSED; + guac_error_message = "Timeout connecting via socket."; + } + else { + guac_error = GUAC_STATUS_INVALID_ARGUMENT; + guac_error_message = "Error attempting to connect via socket."; + } - /* Connection not successful - free resources and go to the next address. */ + /* Some error has occurred - free resources before next iteration. */ close(fd); - current_address = current_address->ai_next; }