Make use of new Xcb Wrapper classes

Use WindowAttributes and WindowGeometry everywhere where the xcb commands
had already been used.

Introduces another wrapper for overlay window and a subclass for query
tree which also wrapps the children command.

composite.cpp

@@ -37,6 +37,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "useractions.h"
 #include "compositingprefs.h"
 #include "notifications.h"
+#include "xcbutils.h"
 
 #include <stdio.h>
 
@@ -874,8 +875,8 @@ xcb_pixmap_t Toplevel::createWindowPixmap()
     XServerGrabber grabber();
     xcb_pixmap_t pix = xcb_generate_id(connection());
     xcb_void_cookie_t namePixmapCookie = xcb_composite_name_window_pixmap_checked(connection(), frameId(), pix);
-    xcb_get_window_attributes_cookie_t attribsCookie = xcb_get_window_attributes(connection(), frameId());
-    xcb_get_geometry_cookie_t geometryCookie = xcb_get_geometry(connection(), frameId());
+    Xcb::WindowAttributes windowAttributes(frameId());
+    Xcb::WindowGeometry windowGeometry(frameId());
     if (xcb_generic_error_t *error = xcb_request_check(connection(), namePixmapCookie)) {
         kDebug(1212) << "Creating window pixmap failed: " << error->error_code;
         free(error);
@@ -883,16 +884,13 @@ xcb_pixmap_t Toplevel::createWindowPixmap()
     }
     // check that the received pixmap is valid and actually matches what we
     // know about the window (i.e. size)
-    ScopedCPointer<xcb_generic_error_t> error;
-    ScopedCPointer<xcb_get_window_attributes_reply_t> attribs(xcb_get_window_attributes_reply(connection(), attribsCookie, &error));
-    if (!error.isNull() || attribs.isNull() || attribs->map_state != XCB_MAP_STATE_VIEWABLE) {
+    if (!windowAttributes || windowAttributes->map_state != XCB_MAP_STATE_VIEWABLE) {
         kDebug(1212) << "Creating window pixmap failed: " << this;
         xcb_free_pixmap(connection(), pix);
         return XCB_PIXMAP_NONE;
     }
-    ScopedCPointer<xcb_get_geometry_reply_t> geometry(xcb_get_geometry_reply(connection(), geometryCookie, &error));
-    if (!error.isNull() || geometry.isNull() ||
-        geometry->width != width() || geometry->height != height()) {
+    if (!windowGeometry ||
+        windowGeometry->width != width() || windowGeometry->height != height()) {
         kDebug(1212) << "Creating window pixmap failed: " << this;
         xcb_free_pixmap(connection(), pix);
         return XCB_PIXMAP_NONE;

overlaywindow.cpp

@@ -54,10 +54,7 @@ bool OverlayWindow::create()
     if (!Xcb::Extensions::self()->isShapeInputAvailable())  // needed in setupOverlay()
         return false;
 #ifdef KWIN_HAVE_XCOMPOSITE_OVERLAY
-    ScopedCPointer<xcb_composite_get_overlay_window_reply_t> overlay =
-        xcb_composite_get_overlay_window_reply(connection(),
-                                               xcb_composite_get_overlay_window(connection(), rootWindow()),
-                                               NULL);
+    Xcb::OverlayWindow overlay(rootWindow());
     if (overlay.isNull()) {
         return false;
     }

workspace.cpp

@@ -409,33 +409,26 @@ void Workspace::init()
         StackingUpdatesBlocker blocker(this);
 
         bool fixoffset = KCmdLineArgs::parsedArgs()->getOption("crashes").toInt() > 0;
-        xcb_connection_t *conn = connection();
 
-        xcb_query_tree_reply_t *tree = xcb_query_tree_reply(conn,
-                            xcb_query_tree_unchecked(conn, rootWindow()), 0);
-        xcb_window_t *wins = xcb_query_tree_children(tree);
+        Xcb::Tree tree(rootWindow());
+        xcb_window_t *wins = xcb_query_tree_children(tree.data());
 
-        QVector<xcb_get_window_attributes_cookie_t> attr_cookies;
-        QVector<xcb_get_geometry_cookie_t> geom_cookies;
-
-        attr_cookies.reserve(tree->children_len);
-        geom_cookies.reserve(tree->children_len);
+        QVector<Xcb::WindowAttributes> windowAttributes(tree->children_len);
+        QVector<Xcb::WindowGeometry> windowGeometries(tree->children_len);
 
         // Request the attributes and geometries of all toplevel windows
         for (int i = 0; i < tree->children_len; i++) {
-            attr_cookies << xcb_get_window_attributes(conn, wins[i]);
-            geom_cookies << xcb_get_geometry(conn, wins[i]);
+            windowAttributes[i] = Xcb::WindowAttributes(wins[i]);
+            windowGeometries[i] = Xcb::WindowGeometry(wins[i]);
         }
 
         // Get the replies
         for (int i = 0; i < tree->children_len; i++) {
-            ScopedCPointer<xcb_get_window_attributes_reply_t> attr
-                        = xcb_get_window_attributes_reply(conn, attr_cookies[i], 0);
-            ScopedCPointer<xcb_get_geometry_reply_t> geometry
-                        = xcb_get_geometry_reply(conn, geom_cookies[i], 0);
+            Xcb::WindowAttributes attr(windowAttributes.at(i));
 
-            if (!attr || !geometry)
+            if (attr.isNull()) {
                 continue;
+            }
 
             if (attr->override_redirect) {
                 if (attr->map_state == XCB_MAP_STATE_VIEWABLE &&
@@ -443,16 +436,15 @@ void Workspace::init()
                     // ### This will request the attributes again
                     createUnmanaged(wins[i]);
             } else if (attr->map_state != XCB_MAP_STATE_UNMAPPED) {
-                if (fixoffset)
-                    fixPositionAfterCrash(wins[i], geometry);
+                if (fixoffset) {
+                    fixPositionAfterCrash(wins[i], windowGeometries[i].data());
+                }
 
                 // ### This will request the attributes again
                 createClient(wins[i], true);
             }
         }
 
-        free(tree);
-
         // Propagate clients, will really happen at the end of the updates blocker block
         updateStackingOrder(true);
 

xcbutils.h

@@ -26,6 +26,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QRect>
 
 #include <xcb/xcb.h>
+#include <xcb/composite.h>
 
 namespace KWin {
 
@@ -149,6 +150,7 @@ private:
 };
 
 typedef Wrapper<xcb_get_window_attributes_reply_t, xcb_get_window_attributes_cookie_t, &xcb_get_window_attributes_reply, &xcb_get_window_attributes_unchecked> WindowAttributes;
+typedef Wrapper<xcb_composite_get_overlay_window_reply_t, xcb_composite_get_overlay_window_cookie_t, &xcb_composite_get_overlay_window_reply, &xcb_composite_get_overlay_window_unchecked> OverlayWindow;
 
 
 class WindowGeometry : public Wrapper<xcb_get_geometry_reply_t, xcb_get_geometry_cookie_t, &xcb_get_geometry_reply, &xcb_get_geometry_unchecked>
@@ -166,6 +168,16 @@ public:
     }
 };
 
+class Tree : public Wrapper<xcb_query_tree_reply_t, xcb_query_tree_cookie_t, &xcb_query_tree_reply, &xcb_query_tree_unchecked>
+{
+public:
+    explicit Tree(WindowId window) : Wrapper<xcb_query_tree_reply_t, xcb_query_tree_cookie_t, &xcb_query_tree_reply, &xcb_query_tree_unchecked>(window) {}
+
+    inline WindowId *children() {
+        return xcb_query_tree_children(data());
+    }
+};
+
 class ExtensionData
 {
 public: