Linux: move X operations from the IO to UI2 thread.

chrome/common/x11_util.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_COMMON_X11_UTIL_H_
 #define CHROME_COMMON_X11_UTIL_H_
 
 // This file declares utility functions for X11 (Linux only).
 //
 // These functions do not require the Xlib headers to be included (which is why
 // we use a void* for Visual*). The Xlib headers are highly polluting so we try
 // hard to limit their spread into the rest of the code.
 
+typedef struct _GdkDrawable GdkWindow;
 typedef struct _GtkWidget GtkWidget;
 typedef unsigned long XID;
 typedef struct _XDisplay Display;
 
+namespace base {
+class Thread;
+}
+
 namespace gfx {
 class Size;
 }
 
 namespace x11_util {
-  // These functions cache their results and must be called from the UI thread.
-  // Currently they don't support multiple screens/displays.
 
-  // Return an X11 connection for the current, primary display.
-  Display* GetXDisplay();
-  // Return true iff the connection supports X shared memory
-  bool QuerySharedMemorySupport(Display* dpy);
-  // Return true iff the display supports Xrender
-  bool QueryRenderSupport(Display* dpy);
+// These functions use the GDK default display and this /must/ be called from
+// the UI thread. Thus, they don't support multiple displays.
 
-  // These functions do not cache their results
+// These functions cache their results.
 
-  // Get the X window id for the default root window
-  XID GetX11RootWindow();
-  // Get the X window id for the given GTK widget.
-  XID GetX11WindowFromGtkWidget(GtkWidget*);
-  // Get a Visual from the given widget. Since we don't include the Xlib
-  // headers, this is returned as a void*.
-  void* GetVisualFromGtkWidget(GtkWidget*);
-  // Return the number of bits-per-pixel for a pixmap of the given depth
-  int BitsPerPixelForPixmapDepth(Display*, int depth);
+// Return an X11 connection for the current, primary display.
+Display* GetXDisplay();
+// Return true iff the connection supports X shared memory
+bool QuerySharedMemorySupport(Display* dpy);
+// Return true iff the display supports Xrender
+bool QueryRenderSupport(Display* dpy);
+// Return the default screen number for the display
+int GetDefaultScreen(Display* display);
 
-  // Return a handle to a server side pixmap. |shared_memory_key| is a SysV
-  // IPC key. The shared memory region must contain 32-bit pixels.
-  XID AttachSharedMemory(Display* display, int shared_memory_support);
-  void DetachSharedMemory(Display* display, XID shmseg);
+// These functions do not cache their results
 
-  // Return a handle to an XRender picture where |pixmap| is a handle to a
-  // pixmap containing Skia ARGB data.
-  XID CreatePictureFromSkiaPixmap(Display* display, XID pixmap);
+// Get the X window id for the default root window
+XID GetX11RootWindow();
+// Get the X window id for the given GTK widget.
+XID GetX11WindowFromGtkWidget(GtkWidget*);
+XID GetX11WindowFromGdkWindow(GdkWindow*);
+// Get a Visual from the given widget. Since we don't include the Xlib
+// headers, this is returned as a void*.
+void* GetVisualFromGtkWidget(GtkWidget*);
+// Return the number of bits-per-pixel for a pixmap of the given depth
+int BitsPerPixelForPixmapDepth(Display*, int depth);
 
-  void FreePicture(Display* display, XID picture);
-  void FreePixmap(Display* display, XID pixmap);
-};
+// Return a handle to a server side pixmap. |shared_memory_key| is a SysV
+// IPC key. The shared memory region must contain 32-bit pixels.
+XID AttachSharedMemory(Display* display, int shared_memory_support);
+void DetachSharedMemory(Display* display, XID shmseg);
+
+// Return a handle to an XRender picture where |pixmap| is a handle to a
+// pixmap containing Skia ARGB data.
+XID CreatePictureFromSkiaPixmap(Display* display, XID pixmap);
+
+void FreePicture(Display* display, XID picture);
+void FreePixmap(Display* display, XID pixmap);
+
+// These functions are for performing X opertions outside of the UI thread.
+
+// Return the Display for the secondary X connection. We keep a second
+// connection around for making X requests outside of the UI thread.
+// This function may only be called from the BACKGROUND_X11 thread.
+Display* GetSecondaryDisplay();
+
+// Since one cannot include both WebKit header and Xlib headers in the same
+// file (due to collisions), we wrap all the Xlib functions that we need here.
+// These functions must be called on the BACKGROUND_X11 thread since they
+// reference GetSecondaryDisplay().
+
+void GetWindowGeometry(int* x, int* y, unsigned* width, unsigned* height,
+                       XID window);
+
+}  // namespace x11_util
 
 #endif  // CHROME_COMMON_X11_UTIL_H_