Simple GEIS demo

#include <geis/geis.h>
#include <iostream>
#include <stdexcept>
#include <X11/Xutil.h>

using namespace std;



class GeisTest
{
public:

  // Sets up a GEIS instance
  GeisTest()
  {
    GeisXcbWinInfo xcbWinInfo;
    xcbWinInfo.display_name = NULL;
    xcbWinInfo.screenp      = NULL;
    xcbWinInfo.window_id    = XRootWindow(XOpenDisplay(NULL), 0);

    GeisWinInfo  winInfo;
    winInfo.win_type = GEIS_XCB_FULL_WINDOW;
    winInfo.win_info = &xcbWinInfo;

    if (geis_init(&winInfo, &geisInstance) != GEIS_STATUS_SUCCESS)
    {
      throw runtime_error("error initializing geis");
    }

    gestureFuncs.added   = GeisTest::gestureAdded;
    gestureFuncs.removed = GeisTest::gestureRemoved;
    gestureFuncs.start   = GeisTest::gestureStart;
    gestureFuncs.update  = GeisTest::gestureUpdate;
    gestureFuncs.finish  = GeisTest::gestureFinish;

    if (geis_subscribe(geisInstance,
                       GEIS_ALL_INPUT_DEVICES,
                       GEIS_ALL_GESTURES,
                       &gestureFuncs,
                       this) != GEIS_STATUS_SUCCESS)
    {
      throw runtime_error("error creating geis subscription");
    }
  }

  // Tears down a GEIS instance
  ~GeisTest()
  {
      geis_finish(geisInstance);
  }

  // an example of how to integrate GEIS into an event loop
  int
  run()
  {
      int fd = -1;
      geis_configuration_get_value(geisInstance, GEIS_CONFIG_UNIX_FD, &fd);

      for(;;)
      {
    fd_set read_fds;
    FD_ZERO(&read_fds);
    FD_SET(0, &read_fds);
    FD_SET(fd, &read_fds);
    int sstat = select(fd+1, &read_fds, NULL, NULL, NULL);

    if (sstat < 0)
      throw runtime_error("error in select");

    if (FD_ISSET(0, &read_fds))
      break;

    if (FD_ISSET(fd, &read_fds))
      geis_event_dispatch(geisInstance);
      }
      return 0;
  }

  static void
  gestureAdded(void* cookie, GeisGestureType type,
           GeisGestureId id, GeisSize numAttrs, GeisGestureAttr* attrs)
  {
    cout << "Gesture added\n";
  }

  static void
  gestureRemoved(void* cookie, GeisGestureType type,
      GeisGestureId id, GeisSize numAttrs, GeisGestureAttr* attrs)
  {
      cout << "Gesture removed\n";
  }

  static void
  gestureStart(void* cookie, GeisGestureType type,
      GeisGestureId id, GeisSize numAttrs, GeisGestureAttr* attrs)
  {
    cout << "Gesture start\n";
  }

  static void
  gestureUpdate(void* cookie, GeisGestureType type,
      GeisGestureId id, GeisSize numAttrs, GeisGestureAttr* attrs)
  {
    cout << "Gesture update\n";
  }

  static void
  gestureFinish(void* cookie, GeisGestureType type,
      GeisGestureId id, GeisSize numAttrs, GeisGestureAttr* attrs)
  {
    cout << "Gesture finish\n";
  }

private:
  GeisInstance     geisInstance;
  GeisGestureFuncs gestureFuncs;
};


int
main(int, char*[])
{
  try
  {
    return GeisTest().run();
  }
  catch (exception& ex)
  {
    cerr << ex.what() << "\n";
    return 1;
  }
}