.. _program_listing_file_lib_utilities_keyboard.cpp:

Program Listing for File keyboard.cpp
=====================================

|exhale_lsh| :ref:`Return to documentation for file <file_lib_utilities_keyboard.cpp>` (``lib/utilities/keyboard.cpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // ---------------------------------------------------------------------
   // This file is part of falcon-core.
   //
   // Copyright (C) 2015, 2016, 2017 Neuro-Electronics Research Flanders
   //
   // Falcon-server is free software: you can redistribute it and/or modify
   // it under the terms of the GNU General Public License as published by
   // the Free Software Foundation, either version 3 of the License, or
   // (at your option) any later version.
   //
   // Falcon-server is distributed in the hope that it will be useful,
   // but WITHOUT ANY WARRANTY; without even the implied warranty of
   // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   // GNU General Public License for more details.
   //
   // You should have received a copy of the GNU General Public License
   // along with falcon-core. If not, see <http://www.gnu.org/licenses/>.
   // ---------------------------------------------------------------------
   
   #include <signal.h>
   #include <sys/select.h>
   #include <termios.h>
   #include <unistd.h>
   
   #include "keyboard.hpp"
   
   int s_interrupted = 0;
   
   int kbhit() {
     struct timeval tv;
     fd_set fds;
     tv.tv_sec = 0;
     tv.tv_usec = 0;
     FD_ZERO(&fds);
     FD_SET(STDIN_FILENO, &fds);  // STDIN_FILENO is 0
     select(STDIN_FILENO + 1, &fds, NULL, NULL, &tv);
     return FD_ISSET(STDIN_FILENO, &fds);
   }
   
   void nonblock(int state) {
     struct termios ttystate;
   
     // get the terminal state
     tcgetattr(STDIN_FILENO, &ttystate);
   
     if (state == 1) {
       // turn off canonical mode
       ttystate.c_lflag &= ~ICANON;
       // turn off echo
       ttystate.c_lflag &= ~ECHO;
       // minimum of number input read.
       ttystate.c_cc[VMIN] = 1;
     } else if (state == 0) {
       // turn on canonical mode
       ttystate.c_lflag |= ICANON;
       // turn on echo
       ttystate.c_lflag |= ECHO;
     }
     // set the terminal attributes.
     tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
   }
   
   void s_signal_handler(int signal_value) { s_interrupted = 1; }
   
   void s_catch_sigint_signal(void) {
     struct sigaction action;
     action.sa_handler = s_signal_handler;
     action.sa_flags = 0;
     sigemptyset(&action.sa_mask);
     sigaction(SIGINT, &action, NULL);
   }