text: /****************************************************************************
  **
  ** Copyright (C) 2015 The Qt Company Ltd.
  ** Contact: http://www.qt.io/licensing/
  **
  ** This file is part of the plugins of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:LGPL21$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see http://www.qt.io/terms-conditions. For further
  ** information use the contact form at http://www.qt.io/contact-us.
  **
  ** GNU Lesser General Public License Usage
  ** Alternatively, this file may be used under the terms of the GNU Lesser
  ** General Public License version 2.1 or version 3 as published by the Free
  ** Software Foundation and appearing in the file LICENSE.LGPLv21 and
  ** LICENSE.LGPLv3 included in the packaging of this file. Please review the
  ** following information to ensure the GNU Lesser General Public License
  ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
  ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
  **
  ** As a special exception, The Qt Company gives you certain additional
  ** rights. These rights are described in The Qt Company LGPL Exception
  ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/
  
  #include "qxcbwmsupport.h"
  #include "qxcbscreen.h"
  
  #include <qdebug.h>
  
  QT_BEGIN_NAMESPACE
  
  QXcbWMSupport::QXcbWMSupport(QXcbConnection *c)
      : QXcbObject(c)
  {
      updateNetWMAtoms();
      updateVirtualRoots();
  }
  
  bool QXcbWMSupport::isSupportedByWM(xcb_atom_t atom) const
  {
      return net_wm_atoms.contains(atom);
  }
  
  
  
  void QXcbWMSupport::updateNetWMAtoms()
  {
      net_wm_atoms.clear();
  
      xcb_window_t root = connection()->primaryScreen()->root();
      int offset = 0;
      int remaining = 0;
      do {
          xcb_get_property_cookie_t cookie = xcb_get_property(xcb_connection(), false, root, atom(QXcbAtom::_NET_SUPPORTED), XCB_ATOM_ATOM, offset, 1024);
          xcb_get_property_reply_t *reply = xcb_get_property_reply(xcb_connection(), cookie, NULL);
          if (!reply)
              break;
  
          remaining = 0;
  
          if (reply->type == XCB_ATOM_ATOM && reply->format == 32) {
              int len = xcb_get_property_value_length(reply)/sizeof(xcb_atom_t);
              xcb_atom_t *atoms = (xcb_atom_t *)xcb_get_property_value(reply);
              int s = net_wm_atoms.size();
              net_wm_atoms.resize(s + len);
              memcpy(net_wm_atoms.data() + s, atoms, len*sizeof(xcb_atom_t));
  
              remaining = reply->bytes_after;
              offset += len;
          }
  
          free(reply);
      } while (remaining > 0);
  }
  
  // update the virtual roots array
  void QXcbWMSupport::updateVirtualRoots()
  {
      net_virtual_roots.clear();
  
      if (!isSupportedByWM(atom(QXcbAtom::_NET_VIRTUAL_ROOTS)))
          return;
  
      xcb_window_t root = connection()->primaryScreen()->root();
      int offset = 0;
      int remaining = 0;
      do {
          xcb_get_property_cookie_t cookie = xcb_get_property(xcb_connection(), false, root, atom(QXcbAtom::_NET_VIRTUAL_ROOTS), XCB_ATOM_WINDOW, offset, 1024);
          xcb_get_property_reply_t *reply = xcb_get_property_reply(xcb_connection(), cookie, NULL);
          if (!reply)
              break;
  
          remaining = 0;
  
          if (reply->type == XCB_ATOM_WINDOW && reply->format == 32) {
              int len = xcb_get_property_value_length(reply)/sizeof(xcb_window_t);
              xcb_window_t *roots = (xcb_window_t *)xcb_get_property_value(reply);
              int s = net_virtual_roots.size();
              net_virtual_roots.resize(s + len);
              memcpy(net_virtual_roots.data() + s, roots, len*sizeof(xcb_window_t));
  
              remaining = reply->bytes_after;
              offset += len;
          }
  
          free(reply);
      } while (remaining > 0);
  
  #ifdef Q_XCB_DEBUG
      qDebug() << "======== updateVirtualRoots";
      for (int i = 0; i < net_virtual_roots.size(); ++i)
          qDebug() << connection()->atomName(net_virtual_roots.at(i));
      qDebug() << "======== updateVirtualRoots";
  #endif
  }
  
  QT_END_NAMESPACE
  