fix getting frame extents on 64-bit platforms, cleanup XGetWindowProperty code

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@48416 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/settings.cpp

@@ -364,36 +364,66 @@ wxFont wxSystemSettingsNative::GetFont( wxSystemFont index )
     return font;
 }
 
-static bool wxXGetWindowProperty(GdkWindow* window, Atom& type, int& format, gulong& nitems, guchar*& data)
+static bool GetFrameExtents(GdkWindow* window, int* left, int* right, int* top, int* bottom)
 {
     bool success = false;
+    Atom property = 0;
 #if GTK_CHECK_VERSION(2, 2, 0)
     if (gtk_check_version(2, 2, 0) == NULL)
     {
-        gulong bytes_after;
+        if (gdk_x11_screen_supports_net_wm_hint(
-        success = XGetWindowProperty(
+                gdk_drawable_get_screen(window),
-            GDK_DISPLAY_XDISPLAY(gdk_drawable_get_display(window)),
+                gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
-            GDK_WINDOW_XWINDOW(window),
+        {
-            gdk_x11_get_xatom_by_name_for_display(
+            success = true;
+            property = gdk_x11_get_xatom_by_name_for_display(
                 gdk_drawable_get_display(window),
-                "_NET_FRAME_EXTENTS"),
+                "_NET_FRAME_EXTENTS");
-            0, // left, right, top, bottom, CARDINAL[4]/32
-            G_MAXLONG, // size of long
-            false, // do not delete property
-            XA_CARDINAL, // 32 bit
-            &type, &format, &nitems, &bytes_after, &data
-            ) == Success;
         }
+    }
+    else
 #endif
+    {
+        if (gdk_net_wm_supports(gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
+        {
+            success = true;
+            property = gdk_x11_get_xatom_by_name("_NET_FRAME_EXTENTS");
+        }
+    }
+    if (success)
+    {
+        Atom type;
+        int format;
+        gulong nitems, bytes_after;
+        long* data = NULL;
+        success = XGetWindowProperty(
+            gdk_x11_drawable_get_xdisplay(window),
+            gdk_x11_drawable_get_xid(window),
+            property,
+            0, 4,
+            false,
+            XA_CARDINAL,
+            &type, &format, &nitems, &bytes_after, (guchar**)&data
+            ) == Success;
+        if (success)
+        {
+            success = data && nitems == 4;
+            if (success)
+            {
+                if (left)   *left   = int(data[0]);
+                if (right)  *right  = int(data[1]);
+                if (top)    *top    = int(data[2]);
+                if (bottom) *bottom = int(data[3]);
+            }
+            if (data)
+                XFree(data);
+        }
+    }
     return success;
 }
 
 int wxSystemSettingsNative::GetMetric( wxSystemMetric index, wxWindow* win )
 {
-    guchar *data = NULL;
-    Atom type;
-    int format;
-    gulong nitems;
     GdkWindow *window = NULL;
     if(win && GTK_WIDGET_REALIZED(win->GetHandle()))
         window = win->GetHandle()->window;
@@ -415,50 +445,22 @@ int wxSystemSettingsNative::GetMetric( wxSystemMetric index, wxWindow* win )
                     return -1; // not a tlw, not sure how to approach
                 else
                 {
-                    // Check if wm supports frame extents - we can't know
-                    // the border widths if it does not.
-#if GTK_CHECK_VERSION(2,2,0)
-                    if (!gtk_check_version(2,2,0))
-                    {
-                        if (!gdk_x11_screen_supports_net_wm_hint(
-                                gdk_drawable_get_screen(window),
-                                gdk_atom_intern("_NET_FRAME_EXTENTS", false) ) )
-                            return -1;
-                    }
-                    else
-#endif
-                    {
-                        if (!gdk_net_wm_supports(gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
-                            return -1;
-                    }
-
                     // Get the frame extents from the windowmanager.
                     // In most cases the top extent is the titlebar, so we use the bottom extent
                     // for the heights.
-                    if (wxXGetWindowProperty(window, type, format, nitems, data))
+                    int right, bottom;
-                    {
+                    if (GetFrameExtents(window, NULL, &right, NULL, &bottom))
-                        int border_return = -1;
-
-                        if ((type == XA_CARDINAL) && (format == 32) && (nitems >= 4) && (data))
                     {
                         switch (index)
                         {
                             case wxSYS_BORDER_X:
                             case wxSYS_EDGE_X:
                             case wxSYS_FRAMESIZE_X:
-                                    border_return = int(data[1]); // width of right extent
+                                return right; // width of right extent
-                                    break;
                             default:
-                                    border_return = int(data[3]); // height of bottom extent
+                                return bottom; // height of bottom extent
-                                    break;
                         }
                     }
-
-                        if (data)
-                            XFree(data);
-
-                        return border_return;
-                    }
                 }
             }
 
@@ -546,22 +548,6 @@ int wxSystemSettingsNative::GetMetric( wxSystemMetric index, wxWindow* win )
                 // No realized window specified, and no implementation for that case yet.
                 return -1;
 
-            // Check if wm supports frame extents - we can't know the caption height if it does not.
-#if GTK_CHECK_VERSION(2,2,0)
-            if (!gtk_check_version(2,2,0))
-            {
-                if (!gdk_x11_screen_supports_net_wm_hint(
-                        gdk_drawable_get_screen(window),
-                        gdk_atom_intern("_NET_FRAME_EXTENTS", false) ) )
-                    return -1;
-            }
-            else
-#endif
-            {
-                if (!gdk_net_wm_supports(gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
-                    return -1;
-            }
-
             wxASSERT_MSG( wxDynamicCast(win, wxTopLevelWindow),
                           wxT("Asking for caption height of a non toplevel window") );
 
@@ -570,19 +556,12 @@ int wxSystemSettingsNative::GetMetric( wxSystemMetric index, wxWindow* win )
             // we could check which is the thickest wm border to decide on which side the
             // titlebar is, but this might lead to interesting behaviours in used code.
             // Reconsider when we have a way to report to the user on which side it is.
-            if (wxXGetWindowProperty(window, type, format, nitems, data))
             {
-                int caption_height = -1;
+                int top;
-
+                if (GetFrameExtents(window, NULL, NULL, &top, NULL))
-                if ((type == XA_CARDINAL) && (format == 32) && (nitems >= 3) && (data))
                 {
-                    caption_height = int(data[2]); // top frame extent
+                    return top; // top frame extent
                 }
-
-                if (data)
-                    XFree(data);
-
-                return caption_height;
             }
 
             // Try a default approach without a window pointer, if possible