libs/backends/GP_X11_Conn.h

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2013 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23 /*
  24  * X11 connection, singleton.
  25  */
  26 struct x11_conn {
  27         Display *dpy;
  28
  29         /* window reference counter */
  30         unsigned int ref_cnt;
  31 };
  32
  33 static struct x11_conn x11_conn = {
  34         .dpy = NULL,
  35         .ref_cnt = 0,
  36 };
  37
  38 static unsigned int x11_open(const char *display)
  39 {
  40         if (x11_conn.ref_cnt != 0)
  41                 return ++x11_conn.ref_cnt;
  42
  43         GP_DEBUG(1, "Opening X11 display '%s'", display);
  44
  45         if (!XInitThreads()) {
  46                 GP_DEBUG(2, "XInitThreads failed");
  47                 return 0;
  48         }
  49
  50         x11_conn.dpy = XOpenDisplay(display);
  51
  52         if (x11_conn.dpy == NULL) {
  53                 GP_WARN("Failed to initialize X11 display");
  54                 return 0;
  55         }
  56
  57         /* Initialized key translation table */
  58         GP_InputDriverX11Init(x11_conn.dpy);
  59
  60         return ++x11_conn.ref_cnt;
  61 }
  62
  63 static void x11_close(void)
  64 {
  65         /* Ignore close requests if connection is closed */
  66         if (x11_conn.ref_cnt == 0)
  67                 return;
  68
  69         if (--x11_conn.ref_cnt != 0)
  70                 return;
  71
  72         GP_DEBUG(1, "Closing X11 display");
  73
  74         XLockDisplay(x11_conn.dpy);
  75
  76         /* I wonder if this is right sequence... */
  77         //XUnlockDisplay(x11_conn.dpy);
  78         XCloseDisplay(x11_conn.dpy);
  79 }