[effects] Allow Built-In Effects using xcbutils.h

xcbutils.h has quite a few inline only implementations such as Xcb::Atom,
the Wrappers, Xcb::Window and the convenient methods. Thus there is
nothing wrong with using it from the built-in Effects.

Xcb::Atom is used in Glide and Logout Effect to get the atom. To keep the
logic of the existing code it got extended by a bool isValid() which
gets the reply and returns true if the atom is set.

REVIEW: 117587

effects/CMakeLists.txt

@@ -1,3 +1,5 @@
+include_directories(${KWIN_SOURCE_DIR}) # for xcbutils.h
+
 set(kwin_effect_OWN_LIBS
     kwineffects
 )

effects/glide/glide.cpp

@@ -32,18 +32,13 @@ namespace KWin
 {
 
 static const int IsGlideWindow = 0x22A982D4;
-static xcb_atom_t slideAtom;
-static const QByteArray s_slideAtomName = QByteArrayLiteral("_KDE_SLIDE");
 
 GlideEffect::GlideEffect()
+    : Effect()
+    , m_atom(QByteArrayLiteral("_KDE_SLIDE"))
 {
-    slideAtom = XCB_ATOM_NONE;
-    xcb_connection_t *c = xcbConnection();
-    const auto cookie = xcb_intern_atom(c, false, s_slideAtomName.length(), s_slideAtomName.constData());
-    QScopedPointer<xcb_intern_atom_reply_t, QScopedPointerPodDeleter> atom(xcb_intern_atom_reply(c, cookie, nullptr));
-    if (atom) {
-        slideAtom = atom->atom;
-        effects->registerPropertyType( slideAtom, true );
+    if (m_atom.isValid()) {
+        effects->registerPropertyType( m_atom, true );
     }
     reconfigure(ReconfigureAll);
     connect(effects, SIGNAL(windowAdded(KWin::EffectWindow*)), this, SLOT(slotWindowAdded(KWin::EffectWindow*)));
@@ -53,8 +48,8 @@ GlideEffect::GlideEffect()
 
 GlideEffect::~GlideEffect()
 {
-    if (slideAtom) {
-        effects->registerPropertyType( slideAtom, false );
+    if (m_atom.isValid()) {
+        effects->registerPropertyType( m_atom, false );
     }
 }
 
@@ -219,7 +214,7 @@ bool GlideEffect::isGlideWindow(EffectWindow* w)
         return false;
     if (w->data(IsGlideWindow).toBool())
         return true;
-    if (slideAtom && !w->readProperty( slideAtom, slideAtom, 32 ).isNull())
+    if (m_atom.isValid() && !w->readProperty( m_atom, m_atom, 32 ).isNull())
         return false;
     if (w->hasDecoration())
         return true;

effects/glide/glide.h

@@ -24,6 +24,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define KWIN_GLIDE_H
 
 #include <kwineffects.h>
+#include <xcbutils.h>
 
 class QTimeLine;
 
@@ -74,6 +75,7 @@ private:
     void glideIn(EffectWindow* w, WindowPaintData& data, const InfoHash::const_iterator &info);
     void glideOut(EffectWindow* w, WindowPaintData& data, const InfoHash::const_iterator &info);
     bool isGlideWindow(EffectWindow* w);
+    Xcb::Atom m_atom;
     InfoHash windows;
     float duration;
     int angle;

effects/logout/logout.cpp

@@ -41,20 +41,15 @@ LogoutEffect::LogoutEffect()
     , logoutWindow(NULL)
     , logoutWindowClosed(true)
     , logoutWindowPassed(false)
-    , logoutAtom(XCB_ATOM_NONE)
+    , logoutAtom(QByteArrayLiteral("_KDE_LOGGING_OUT"))
     , canDoPersistent(false)
     , ignoredWindows()
     , m_vignettingShader(NULL)
     , m_blurShader(NULL)
     , m_shadersDir(QStringLiteral("kwin/shaders/1.10/"))
 {
-    xcb_connection_t *c = xcbConnection();
-    const QByteArray &name = QByteArrayLiteral("_KDE_LOGGING_OUT");
-    const auto cookie = xcb_intern_atom(c, false, name.length(), name.constData());
-    QScopedPointer<xcb_intern_atom_reply_t, QScopedPointerPodDeleter> atom(xcb_intern_atom_reply(c, cookie, nullptr));
-    if (atom) {
+    if (logoutAtom.isValid()) {
         // Persistent effect
-        logoutAtom = atom->atom;
         effects->registerPropertyType(logoutAtom, true);
     }
 

effects/logout/logout.h

@@ -24,6 +24,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define KWIN_LOGOUT_H
 
 #include <kwineffects.h>
+#include <xcbutils.h>
 
 
 namespace KWin
@@ -69,7 +70,7 @@ private:
     bool logoutWindowPassed;
 
     // Persistent effect
-    xcb_atom_t logoutAtom;
+    Xcb::Atom logoutAtom;
     bool canDoPersistent;
     EffectWindowList ignoredWindows;
 

xcbutils.h

@@ -472,6 +472,14 @@ public:
         (const_cast<Atom*>(this))->getReply();
         return m_atom;
     }
+    bool isValid() {
+        getReply();
+        return m_atom != XCB_ATOM_NONE;
+    }
+    bool isValid() const {
+        (const_cast<Atom*>(this))->getReply();
+        return m_atom != XCB_ATOM_NONE;
+    }
 
     inline const QByteArray &name() const {
         return m_name;