Fix tab dragging in unity2d

ui/base/x/x11_util.cc

 // Copyright (c) 2012 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.
 
 // This file defines utility functions for X11 (Linux only). This code has been
 // ported from XCB since we can't use XCB on Ubuntu while its 32-bit support
 // remains woefully incomplete.
 
 #include "ui/base/x/x11_util.h"
 
 #include <ctype.h>
 #include <sys/ipc.h>
 #include <sys/shm.h>
 
 #include <list>
 #include <map>
 #include <utility>
 #include <vector>
 
 #include <X11/extensions/Xrandr.h>
 #include <X11/extensions/randr.h>
+#include <X11/extensions/shape.h>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/message_loop.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
@@ skipping 573 matching lines @@
     return false;
 
   if (!XTranslateCoordinates(GetXDisplay(), window, root,
                              0, 0, &x, &y, &child))
     return false;
 
   *rect = gfx::Rect(x, y, width, height);
   return true;
 }
 
+
+bool WindowContainsPoint(XID window, gfx::Point screen_loc) {
+  gfx::Rect window_rect;
+  if (!GetWindowRect(window, &window_rect))
+    return false;
+
+  if (!window_rect.Contains(screen_loc))
+    return false;
+
+  // According to http://www.x.org/releases/X11R7.6/doc/libXext/shapelib.html,
+  // if an X display supports the shape extension the bounds of a window are
+  // defined as the intersection of the window bounds and the interior
+  // rectangles. This means to determine if a point is inside a window for the
+  // purpose of input handling we have to check the rectangles in the ShapeInput
+  // list.
+  int dummy;
+  if (XShapeQueryExtension(ui::GetXDisplay(), &dummy, &dummy)) {

[sadrul, 2012/09/24 23:39:24]

It would make sense to cache the return value of XShapeQueryExtension

+    int input_rects_size = 0;
+    XRectangle* input_rects = XShapeGetRectangles(
+        ui::GetXDisplay(), window, ShapeInput, &input_rects_size, &dummy);
+    bool is_in_input_rects = false;
+    for (int i = 0; i < input_rects_size; ++i) {
+      gfx::Rect input_rect =
+          gfx::Rect(input_rects[i].x, input_rects[i].y,
+                    input_rects[i].width, input_rects[i].height);
+      if (input_rect.Contains(screen_loc)) {
+        is_in_input_rects = true;
+        break;
+      }
+    }

[Elliot Glaysher, 2012/09/24 23:35:05]

You'll need an XFree(input_rects); here.

+    if (!is_in_input_rects)
+      return false;
+  }
+
+  return true;
+}
+
+
 bool PropertyExists(XID window, const std::string& property_name) {
   Atom type = None;
   int format = 0;  // size in bits of each item in 'property'
   unsigned long num_items = 0;
   unsigned char* property = NULL;
 
   int result = GetProperty(window, property_name, 1,
                            &type, &format, &num_items, &property);
   if (result != Success)
     return false;
@@ skipping 956 matching lines @@
       << "request_code " << static_cast<int>(error_event.request_code) << ", "
       << "minor_code " << static_cast<int>(error_event.minor_code)
       << " (" << request_str << ")";
 }
 
 // ----------------------------------------------------------------------------
 // End of x11_util_internal.h
 
 
 }  // namespace ui