xcb: remove confusing indirections for qt selection owner

This makes it more obvious that clipboard and DnD use the
same selection owner (QXcbConnection::qtSelectionOwner()).

This way we can also drop some QT_NO_CLIPBOARD defines.
These defines actually are broken, but that is out-of-scope
for this patch.

And renamed the functions according to Qt guidelines:

getSelectionOwner()   -> selectionOwner()
getQtSelectionOwner() -> qtSelectionOwner()

The previous naming probably was influenced by underlying
C API - xcb_get_selection_owner().

Change-Id: I467f1a3dbe75b4e8fd41c7e66ca9b0e25ef1039c
Reviewed-by: Liang Qi <liang.qi@qt.io>

6 files changed, 40 insertions, 76 deletions

diff --git a/src/plugins/platforms/xcb/qxcbclipboard.cpp b/src/plugins/platforms/xcb/qxcbclipboard.cpp
index dcffa568c4..d41ddebc0d 100644
--- a/src/plugins/platforms/xcb/qxcbclipboard.cpp
+++ b/src/plugins/platforms/xcb/qxcbclipboard.cpp
@@ -83,7 +83,7 @@ public:
 
     bool isEmpty() const
     {
-        return m_clipboard->getSelectionOwner(modeAtom) == XCB_NONE;
+        return m_clipboard->connection()->selectionOwner(modeAtom) == XCB_NONE;
     }
 
 protected:
@@ -231,14 +231,15 @@ QXcbClipboard::QXcbClipboard(QXcbConnection *c)
     m_clientClipboard[QClipboard::Selection] = nullptr;
     m_timestamp[QClipboard::Clipboard] = XCB_CURRENT_TIME;
     m_timestamp[QClipboard::Selection] = XCB_CURRENT_TIME;
-    m_owner = connection()->getQtSelectionOwner();
 
     if (connection()->hasXFixes()) {
         const uint32_t mask = XCB_XFIXES_SELECTION_EVENT_MASK_SET_SELECTION_OWNER |
                 XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_WINDOW_DESTROY |
                 XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_CLIENT_CLOSE;
-        xcb_xfixes_select_selection_input_checked(xcb_connection(), m_owner, XCB_ATOM_PRIMARY, mask);
-        xcb_xfixes_select_selection_input_checked(xcb_connection(), m_owner, atom(QXcbAtom::CLIPBOARD), mask);
+        xcb_xfixes_select_selection_input_checked(xcb_connection(), connection()->qtSelectionOwner(),
+                                                  XCB_ATOM_PRIMARY, mask);
+        xcb_xfixes_select_selection_input_checked(xcb_connection(), connection()->qtSelectionOwner(),
+                                                  atom(QXcbAtom::CLIPBOARD), mask);
     }
 
     // xcb_change_property_request_t and xcb_get_property_request_t are the same size
@@ -256,13 +257,16 @@ QXcbClipboard::~QXcbClipboard()
         auto reply = Q_XCB_REPLY(xcb_get_selection_owner, xcb_connection(), atom(QXcbAtom::CLIPBOARD_MANAGER));
         if (reply && reply->owner != XCB_NONE) {
             // we delete the property so the manager saves all TARGETS.
-            xcb_delete_property(xcb_connection(), m_owner, atom(QXcbAtom::_QT_SELECTION));
-            xcb_convert_selection(xcb_connection(), m_owner, atom(QXcbAtom::CLIPBOARD_MANAGER), atom(QXcbAtom::SAVE_TARGETS),
+            xcb_delete_property(xcb_connection(), connection()->qtSelectionOwner(),
+                                atom(QXcbAtom::_QT_SELECTION));
+            xcb_convert_selection(xcb_connection(), connection()->qtSelectionOwner(),
+                                  atom(QXcbAtom::CLIPBOARD_MANAGER), atom(QXcbAtom::SAVE_TARGETS),
                                   atom(QXcbAtom::_QT_SELECTION), connection()->time());
             connection()->sync();
 
             // waiting until the clipboard manager fetches the content.
-            if (auto event = waitForClipboardEvent(m_owner, XCB_SELECTION_NOTIFY, true)) {
+            if (auto event = waitForClipboardEvent(connection()->qtSelectionOwner(),
+                                                   XCB_SELECTION_NOTIFY, true)) {
                 free(event);
             } else {
                 qCWarning(lcQpaClipboard, "QXcbClipboard: Unable to receive an event from the "
@@ -289,11 +293,6 @@ bool QXcbClipboard::handlePropertyNotify(const xcb_generic_event_t *event)
     return (*it)->updateIncrementalProperty(propertyNotify);
 }
 
-xcb_window_t QXcbClipboard::getSelectionOwner(xcb_atom_t atom) const
-{
-    return connection()->getSelectionOwner(atom);
-}
-
 xcb_atom_t QXcbClipboard::atomForMode(QClipboard::Mode mode) const
 {
     if (mode == QClipboard::Clipboard)
@@ -319,8 +318,8 @@ QMimeData * QXcbClipboard::mimeData(QClipboard::Mode mode)
     if (mode > QClipboard::Selection)
         return nullptr;
 
-    xcb_window_t clipboardOwner = getSelectionOwner(atomForMode(mode));
-    if (clipboardOwner == owner()) {
+    xcb_window_t clipboardOwner = connection()->selectionOwner(atomForMode(mode));
+    if (clipboardOwner == connection()->qtSelectionOwner()) {
         return m_clientClipboard[mode];
     } else {
         if (!m_xClipboard[mode])
@@ -362,7 +361,7 @@ void QXcbClipboard::setMimeData(QMimeData *data, QClipboard::Mode mode)
         connection()->setTime(connection()->getTimestamp());
 
     if (data) {
-        newOwner = owner();
+        newOwner = connection()->qtSelectionOwner();
 
         m_clientClipboard[mode] = data;
         m_timestamp[mode] = connection()->time();
@@ -370,7 +369,7 @@ void QXcbClipboard::setMimeData(QMimeData *data, QClipboard::Mode mode)
 
     xcb_set_selection_owner(xcb_connection(), newOwner, modeAtom, connection()->time());
 
-    if (getSelectionOwner(modeAtom) != newOwner) {
+    if (connection()->selectionOwner(modeAtom) != newOwner) {
         qCWarning(lcQpaClipboard, "QXcbClipboard::setMimeData: Cannot set X11 selection owner");
     }
 
@@ -386,10 +385,11 @@ bool QXcbClipboard::supportsMode(QClipboard::Mode mode) const
 
 bool QXcbClipboard::ownsMode(QClipboard::Mode mode) const
 {
-    if (m_owner == XCB_NONE || mode > QClipboard::Selection)
+    if (connection()->qtSelectionOwner() == XCB_NONE || mode > QClipboard::Selection)
         return false;
 
-    Q_ASSERT(m_timestamp[mode] == XCB_CURRENT_TIME || getSelectionOwner(atomForMode(mode)) == m_owner);
+    Q_ASSERT(m_timestamp[mode] == XCB_CURRENT_TIME
+             || connection()->selectionOwner(atomForMode(mode)) == connection()->qtSelectionOwner());
 
     return m_timestamp[mode] != XCB_CURRENT_TIME;
 }
@@ -438,11 +438,6 @@ void QXcbClipboard::setRequestor(xcb_window_t window)
     m_requestor = window;
 }
 
-xcb_window_t QXcbClipboard::owner() const
-{
-    return m_owner;
-}
-
 xcb_atom_t QXcbClipboard::sendTargetsSelection(QMimeData *d, xcb_window_t window, xcb_atom_t property)
 {
     QList<xcb_atom_t> types;
@@ -521,7 +516,7 @@ void QXcbClipboard::handleSelectionClearRequest(xcb_selection_clear_event_t *eve
 //          XGetSelectionOwner(dpy, XA_PRIMARY),
 //          xevent->xselectionclear.time, d->timestamp);
 
-    xcb_window_t newOwner = getSelectionOwner(event->selection);
+    xcb_window_t newOwner = connection()->selectionOwner(event->selection);
 
     /* If selection ownership was given up voluntarily from QClipboard::clear(), then we do nothing here
     since its already handled in setMimeData. Otherwise, the event must have come from another client
@@ -668,7 +663,7 @@ void QXcbClipboard::handleXFixesSelectionRequest(xcb_xfixes_selection_notify_eve
     // Note1: Here we care only about the xfixes events that come from other processes.
     // Note2: If the QClipboard::clear() is issued, event->owner is XCB_NONE,
     // so we check selection_timestamp to not handle our own QClipboard::clear().
-    if (event->owner != owner() && event->selection_timestamp > m_timestamp[mode]) {
+    if (event->owner != connection()->qtSelectionOwner() && event->selection_timestamp > m_timestamp[mode]) {
         if (!m_xClipboard[mode]) {
             m_xClipboard[mode].reset(new QXcbClipboardMime(mode, this));
         } else {
diff --git a/src/plugins/platforms/xcb/qxcbclipboard.h b/src/plugins/platforms/xcb/qxcbclipboard.h
index 51ae0dc1ee..a33f43c435 100644
--- a/src/plugins/platforms/xcb/qxcbclipboard.h
+++ b/src/plugins/platforms/xcb/qxcbclipboard.h
@@ -97,8 +97,6 @@ public:
     xcb_window_t requestor() const;
     void setRequestor(xcb_window_t window);
 
-    xcb_window_t owner() const;
-
     void handleSelectionRequest(xcb_selection_request_event_t *event);
     void handleSelectionClearRequest(xcb_selection_clear_event_t *event);
     void handleXFixesSelectionRequest(xcb_xfixes_selection_notify_event_t *event);
@@ -110,7 +108,6 @@ public:
 
     bool handlePropertyNotify(const xcb_generic_event_t *event);
 
-    xcb_window_t getSelectionOwner(xcb_atom_t atom) const;
     QByteArray getSelection(xcb_atom_t selection, xcb_atom_t target, xcb_atom_t property, xcb_timestamp_t t = 0);
 
     int increment() const { return m_maxPropertyRequestDataBytes; }
@@ -133,7 +130,6 @@ private:
     xcb_timestamp_t m_timestamp[2];
 
     xcb_window_t m_requestor = XCB_NONE;
-    xcb_window_t m_owner = XCB_NONE;
 
     static const int clipboard_timeout;
 
diff --git a/src/plugins/platforms/xcb/qxcbconnection.cpp b/src/plugins/platforms/xcb/qxcbconnection.cpp
index ac818b984b..d6257c70b5 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection.cpp
@@ -868,7 +868,7 @@ xcb_timestamp_t QXcbConnection::getTimestamp()
     return timestamp;
 }
 
-xcb_window_t QXcbConnection::getSelectionOwner(xcb_atom_t atom) const
+xcb_window_t QXcbConnection::selectionOwner(xcb_atom_t atom) const
 {
     auto reply = Q_XCB_REPLY(xcb_get_selection_owner, xcb_connection(), atom);
     if (!reply) {
@@ -879,7 +879,7 @@ xcb_window_t QXcbConnection::getSelectionOwner(xcb_atom_t atom) const
     return reply->owner;
 }
 
-xcb_window_t QXcbConnection::getQtSelectionOwner()
+xcb_window_t QXcbConnection::qtSelectionOwner()
 {
     if (!m_qtSelectionOwner) {
         xcb_screen_t *xcbScreen = primaryVirtualDesktop()->screen();
diff --git a/src/plugins/platforms/xcb/qxcbconnection.h b/src/plugins/platforms/xcb/qxcbconnection.h
index b0b26085d7..13917ed1df 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.h
+++ b/src/plugins/platforms/xcb/qxcbconnection.h
@@ -191,8 +191,8 @@ public:
     inline void setNetWmUserTime(xcb_timestamp_t t) { if (timeGreaterThan(t, m_netWmUserTime)) m_netWmUserTime = t; }
 
     xcb_timestamp_t getTimestamp();
-    xcb_window_t getSelectionOwner(xcb_atom_t atom) const;
-    xcb_window_t getQtSelectionOwner();
+    xcb_window_t selectionOwner(xcb_atom_t atom) const;
+    xcb_window_t qtSelectionOwner();
 
     void setButtonState(Qt::MouseButton button, bool down);
     Qt::MouseButtons buttonState() const { return m_buttonState; }
diff --git a/src/plugins/platforms/xcb/qxcbdrag.cpp b/src/plugins/platforms/xcb/qxcbdrag.cpp
index d2143ce953..4437da3520 100644
--- a/src/plugins/platforms/xcb/qxcbdrag.cpp
+++ b/src/plugins/platforms/xcb/qxcbdrag.cpp
@@ -174,11 +174,9 @@ void QXcbDrag::startDrag()
 {
     init();
 
-#ifndef QT_NO_CLIPBOARD
-    qCDebug(lcQpaXDnd) << "starting drag where source:" << connection()->clipboard()->owner();
-    xcb_set_selection_owner(xcb_connection(), connection()->clipboard()->owner(),
+    qCDebug(lcQpaXDnd) << "starting drag where source:" << connection()->qtSelectionOwner();
+    xcb_set_selection_owner(xcb_connection(), connection()->qtSelectionOwner(),
                             atom(QXcbAtom::XdndSelection), connection()->time());
-#endif
 
     QStringList fmts = QXcbMime::formatsHelper(drag()->mimeData());
     for (int i = 0; i < fmts.size(); ++i) {
@@ -188,12 +186,11 @@ void QXcbDrag::startDrag()
                 drag_types.append(atoms.at(j));
         }
     }
-#ifndef QT_NO_CLIPBOARD
+
     if (drag_types.size() > 3)
-        xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, connection()->clipboard()->owner(),
+        xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, connection()->qtSelectionOwner(),
                             atom(QXcbAtom::XdndTypelist),
                             XCB_ATOM_ATOM, 32, drag_types.size(), (const void *)drag_types.constData());
-#endif
 
     setUseCompositing(current_virtual_desktop->compositingActive());
     setScreen(current_virtual_desktop->screens().constFirst()->screen());
@@ -444,11 +441,7 @@ void QXcbDrag::move(const QPoint &globalPos, Qt::MouseButtons b, Qt::KeyboardMod
             enter.window = target;
             enter.format = 32;
             enter.type = atom(QXcbAtom::XdndEnter);
-#ifndef QT_NO_CLIPBOARD
-            enter.data.data32[0] = connection()->clipboard()->owner();
-#else
-            enter.data.data32[0] = 0;
-#endif
+            enter.data.data32[0] = connection()->qtSelectionOwner();
             enter.data.data32[1] = flags;
             enter.data.data32[2] = drag_types.size() > 0 ? drag_types.at(0) : 0;
             enter.data.data32[3] = drag_types.size() > 1 ? drag_types.at(1) : 0;
@@ -479,11 +472,7 @@ void QXcbDrag::move(const QPoint &globalPos, Qt::MouseButtons b, Qt::KeyboardMod
         move.window = target;
         move.format = 32;
         move.type = atom(QXcbAtom::XdndPosition);
-#ifndef QT_NO_CLIPBOARD
-        move.data.data32[0] = connection()->clipboard()->owner();
-#else
-        move.data.data32[0] = 0;
-#endif
+        move.data.data32[0] = connection()->qtSelectionOwner();
         move.data.data32[1] = 0; // flags
         move.data.data32[2] = (globalPos.x() << 16) + globalPos.y();
         move.data.data32[3] = connection()->time();
@@ -529,11 +518,7 @@ void QXcbDrag::drop(const QPoint &globalPos, Qt::MouseButtons b, Qt::KeyboardMod
     drop.window = current_target;
     drop.format = 32;
     drop.type = atom(QXcbAtom::XdndDrop);
-#ifndef QT_NO_CLIPBOARD
-    drop.data.data32[0] = connection()->clipboard()->owner();
-#else
-    drop.data.data32[0] = 0;
-#endif
+    drop.data.data32[0] = connection()->qtSelectionOwner();
     drop.data.data32[1] = 0; // flags
     drop.data.data32[2] = connection()->time();
 
@@ -640,7 +625,7 @@ void QXcbDrag::setActionList(Qt::DropAction requestedAction, Qt::DropActions sup
     checkAppend(Qt::LinkAction);
 
     if (current_actions != actions) {
-        xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, connection()->clipboard()->owner(),
+        xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, connection()->qtSelectionOwner(),
                             atom(QXcbAtom::XdndActionList),
                             XCB_ATOM_ATOM, 32, actions.size(), actions.constData());
         current_actions = actions;
@@ -861,11 +846,9 @@ void QXcbDrag::handle_xdnd_position(QPlatformWindow *w, const xcb_client_message
 
     qCDebug(lcQpaXDnd) << "sending XdndStatus to source:" << xdnd_dragsource;
 
-#ifndef QT_NO_CLIPBOARD
-    if (xdnd_dragsource == connection()->clipboard()->owner())
+    if (xdnd_dragsource == connection()->qtSelectionOwner())
         handle_xdnd_status(&response);
     else
-#endif
         xcb_send_event(xcb_connection(), false, current_proxy_target,
                        XCB_EVENT_MASK_NO_EVENT, (const char *)&response);
 }
@@ -931,11 +914,7 @@ void QXcbDrag::handle_xdnd_status(const xcb_client_message_event_t *event)
 
 void QXcbDrag::handleStatus(const xcb_client_message_event_t *event)
 {
-    if (
-#ifndef QT_NO_CLIPBOARD
-            event->window != connection()->clipboard()->owner() ||
-#endif
-            !drag())
+    if (event->window != connection()->qtSelectionOwner() || !drag())
         return;
 
     xcb_client_message_event_t *lastEvent = const_cast<xcb_client_message_event_t *>(event);
@@ -992,11 +971,7 @@ void QXcbDrag::send_leave()
     leave.window = current_target;
     leave.format = 32;
     leave.type = atom(QXcbAtom::XdndLeave);
-#ifndef QT_NO_CLIPBOARD
-    leave.data.data32[0] = connection()->clipboard()->owner();
-#else
-    leave.data.data32[0] = 0;
-#endif
+    leave.data.data32[0] = connection()->qtSelectionOwner();
     leave.data.data32[1] = 0; // flags
     leave.data.data32[2] = 0; // x, y
     leave.data.data32[3] = 0; // w, h
@@ -1091,10 +1066,8 @@ void QXcbDrag::handleFinished(const xcb_client_message_event_t *event)
     // Source receives XdndFinished when target is done processing the drop data.
     qCDebug(lcQpaXDnd) << "source:" << event->window << "received XdndFinished";
 
-#ifndef QT_NO_CLIPBOARD
-    if (event->window != connection()->clipboard()->owner())
+    if (event->window != connection()->qtSelectionOwner())
         return;
-#endif
 
     const unsigned long *l = (const unsigned long *)event->data.data32;
     if (l[0]) {
@@ -1369,7 +1342,7 @@ QVariant QXcbDropData::xdndObtainData(const QByteArray &format, QMetaType reques
         return result;
 
 #ifndef QT_NO_CLIPBOARD
-    if (c->clipboard()->getSelectionOwner(drag->atom(QXcbAtom::XdndSelection)) == XCB_NONE)
+    if (c->selectionOwner(c->atom(QXcbAtom::XdndSelection)) == XCB_NONE)
         return result; // should never happen?
 
     xcb_atom_t xdnd_selection = c->atom(QXcbAtom::XdndSelection);
diff --git a/src/plugins/platforms/xcb/qxcbscreen.cpp b/src/plugins/platforms/xcb/qxcbscreen.cpp
index effd7c6da6..6524397cef 100644
--- a/src/plugins/platforms/xcb/qxcbscreen.cpp
+++ b/src/plugins/platforms/xcb/qxcbscreen.cpp
@@ -62,7 +62,7 @@ QXcbVirtualDesktop::QXcbVirtualDesktop(QXcbConnection *connection, xcb_screen_t
 {
     const QByteArray cmAtomName =  "_NET_WM_CM_S" + QByteArray::number(m_number);
     m_net_wm_cm_atom = connection->internAtom(cmAtomName.constData());
-    m_compositingActive = connection->getSelectionOwner(m_net_wm_cm_atom);
+    m_compositingActive = connection->selectionOwner(m_net_wm_cm_atom);
 
     m_workArea = getWorkArea();
 
@@ -177,7 +177,7 @@ bool QXcbVirtualDesktop::compositingActive() const
     if (connection()->hasXFixes())
         return m_compositingActive;
     else
-        return connection()->getSelectionOwner(m_net_wm_cm_atom);
+        return connection()->selectionOwner(m_net_wm_cm_atom);
 }
 
 void QXcbVirtualDesktop::handleXFixesSelectionNotify(xcb_xfixes_selection_notify_event_t *notify_event)
@@ -192,7 +192,7 @@ void QXcbVirtualDesktop::subscribeToXFixesSelectionNotify()
         const uint32_t mask = XCB_XFIXES_SELECTION_EVENT_MASK_SET_SELECTION_OWNER |
                               XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_WINDOW_DESTROY |
                               XCB_XFIXES_SELECTION_EVENT_MASK_SELECTION_CLIENT_CLOSE;
-        xcb_xfixes_select_selection_input_checked(xcb_connection(), connection()->getQtSelectionOwner(), m_net_wm_cm_atom, mask);
+        xcb_xfixes_select_selection_input_checked(xcb_connection(), connection()->qtSelectionOwner(), m_net_wm_cm_atom, mask);
     }
 }