File indexing completed on 2025-03-16 11:21:57

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2019 Roman Gilg <subdiff@gmail.com>
     SPDX-FileCopyrightText: 2021 David Edmundson <davidedmundson@kde.org>
     SPDX-FileCopyrightText: 2021 David Redondo <kde@david-redondo.de>
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 #include "dnd.h"
 
 #include "databridge.h"
 #include "drag_wl.h"
 #include "drag_x.h"
 #include "selection_source.h"
 
 #include "atoms.h"
 #include "wayland/compositor_interface.h"
 #include "wayland/datasource_interface.h"
 #include "wayland/seat_interface.h"
 #include "wayland_server.h"
 #include "window.h"
 #include "workspace.h"
 #include "xwayland.h"
 #include "xwldrophandler.h"
 
 #include <QMouseEvent>
 
 #include <xcb/xcb.h>
 
 namespace KWin
 {
 namespace Xwl
 {
 
 // version of DnD support in X
 const static uint32_t s_version = 5;
 uint32_t Dnd::version()
 {
     return s_version;
 }
 
 XwlDropHandler *Dnd::dropHandler() const
 {
     return m_dropHandler;
 }
 
 Dnd::Dnd(xcb_atom_t atom, QObject *parent)
     : Selection(atom, parent)
     , m_dropHandler(new XwlDropHandler(this))
 {
     xcb_connection_t *xcbConn = kwinApp()->x11Connection();
 
     const uint32_t dndValues[] = {XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY | XCB_EVENT_MASK_PROPERTY_CHANGE};
     xcb_create_window(xcbConn,
                       XCB_COPY_FROM_PARENT,
                       window(),
                       kwinApp()->x11RootWindow(),
                       0, 0,
                       8192, 8192, // TODO: get current screen size and connect to changes
                       0,
                       XCB_WINDOW_CLASS_INPUT_OUTPUT,
                       XCB_COPY_FROM_PARENT,
                       XCB_CW_EVENT_MASK,
                       dndValues);
     registerXfixes();
 
     xcb_change_property(xcbConn,
                         XCB_PROP_MODE_REPLACE,
                         window(),
                         atoms->xdnd_aware,
                         XCB_ATOM_ATOM,
                         32, 1, &s_version);
     xcb_flush(xcbConn);
 
     connect(waylandServer()->seat(), &KWaylandServer::SeatInterface::dragStarted, this, &Dnd::startDrag);
     connect(waylandServer()->seat(), &KWaylandServer::SeatInterface::dragEnded, this, &Dnd::endDrag);
 }
 
 void Dnd::doHandleXfixesNotify(xcb_xfixes_selection_notify_event_t *event)
 {
     if (qobject_cast<XToWlDrag *>(m_currentDrag)) {
         // X drag is in progress, rogue X client took over the selection.
         return;
     }
     if (m_currentDrag) {
         // Wl drag is in progress - don't overwrite by rogue X client,
         // get it back instead!
         ownSelection(true);
         return;
     }
     createX11Source(nullptr);
     const auto *seat = waylandServer()->seat();
     auto *originSurface = seat->focusedPointerSurface();
     if (!originSurface) {
         return;
     }
     if (originSurface->client() != waylandServer()->xWaylandConnection()) {
         // focused surface client is not Xwayland - do not allow drag to start
         // TODO: can we make this stronger (window id comparison)?
         return;
     }
     if (!seat->isPointerButtonPressed(Qt::LeftButton)) {
         // we only allow drags to be started on (left) pointer button being
         // pressed for now
         return;
     }
     createX11Source(event);
     X11Source *source = x11Source();
     if (!source) {
         return;
     }
     m_currentDrag = new XToWlDrag(source, this);
 }
 
 void Dnd::x11OffersChanged(const QStringList &added, const QStringList &removed)
 {
 }
 
 bool Dnd::handleClientMessage(xcb_client_message_event_t *event)
 {
     for (Drag *drag : std::as_const(m_oldDrags)) {
         if (drag->handleClientMessage(event)) {
             return true;
         }
     }
     if (m_currentDrag && m_currentDrag->handleClientMessage(event)) {
         return true;
     }
     return false;
 }
 
 DragEventReply Dnd::dragMoveFilter(Window *target, const QPoint &pos)
 {
     Q_ASSERT(m_currentDrag);
     return m_currentDrag->moveFilter(target, pos);
 }
 
 void Dnd::startDrag()
 {
     auto dragSource = waylandServer()->seat()->dragSource();
     if (qobject_cast<XwlDataSource *>(dragSource)) {
         return;
     }
 
     // There can only ever be one Wl native drag at the same time.
     Q_ASSERT(!m_currentDrag);
 
     // New Wl to X drag, init drag and Wl source.
     m_currentDrag = new WlToXDrag(this);
     auto source = new WlSource(this);
     source->setDataSourceIface(dragSource);
      connect(dragSource, &KWaylandServer::AbstractDataSource::aboutToBeDestroyed, this, [this, source] {
         if (source == wlSource()) {
             setWlSource(nullptr);
         }
     });
     setWlSource(source);
     ownSelection(true);
 }
 
 void Dnd::endDrag()
 {
     Q_ASSERT(m_currentDrag);
 
     connect(m_currentDrag, &Drag::finish, this, &Dnd::clearOldDrag);
     m_oldDrags << m_currentDrag;
 
     m_currentDrag = nullptr;
 }
 
 void Dnd::clearOldDrag(Drag *drag)
 {
     m_oldDrags.removeOne(drag);
     delete drag;
 }
 
 using DnDAction = KWaylandServer::DataDeviceManagerInterface::DnDAction;
 using DnDActions = KWaylandServer::DataDeviceManagerInterface::DnDActions;
 
 DnDAction Dnd::atomToClientAction(xcb_atom_t atom)
 {
     if (atom == atoms->xdnd_action_copy) {
         return DnDAction::Copy;
     } else if (atom == atoms->xdnd_action_move) {
         return DnDAction::Move;
     } else if (atom == atoms->xdnd_action_ask) {
         // we currently do not support it - need some test client first
         return DnDAction::None;
         //        return DnDAction::Ask;
     }
     return DnDAction::None;
 }
 
 xcb_atom_t Dnd::clientActionToAtom(DnDAction action)
 {
     if (action == DnDAction::Copy) {
         return atoms->xdnd_action_copy;
     } else if (action == DnDAction::Move) {
         return atoms->xdnd_action_move;
     } else if (action == DnDAction::Ask) {
         // we currently do not support it - need some test client first
         return XCB_ATOM_NONE;
         //        return atoms->xdnd_action_ask;
     }
     return XCB_ATOM_NONE;
 }
 
 } // namespace Xwl
 } // namespace KWin