linux_aura: Redo how memory is handled in clipboard/drag code.

ui/base/x/x11_util.h

 // 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.
 
 #ifndef UI_BASE_X_X11_UTIL_H_
 #define UI_BASE_X_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.
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/event_types.h"
+#include "base/memory/ref_counted_memory.h"
 #include "ui/base/events/event_constants.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 #include "ui/base/ui_export.h"
 #include "ui/gfx/point.h"
 
 typedef unsigned long Atom;
 typedef unsigned long XID;
 typedef unsigned long XSharedMemoryId;  // ShmSeg in the X headers.
 typedef struct _XDisplay Display;
 typedef unsigned long Cursor;
@@ skipping 130 matching lines @@
 UI_EXPORT bool GetWindowRect(XID window, gfx::Rect* rect);
 
 // Returns true if |window| contains the point |screen_loc|.
 UI_EXPORT bool WindowContainsPoint(XID window, gfx::Point screen_loc);
 
 // Return true if |window| has any property with |property_name|.
 UI_EXPORT bool PropertyExists(XID window, const std::string& property_name);
 
 // Returns the raw bytes from a property with minimal
 // interpretation. |out_data| should be freed by XFree() after use.
-UI_EXPORT bool GetRawBytesOfProperty(XID window,
-                                     Atom property,
-                                     unsigned char** out_data,
-                                     size_t* out_data_bytes,
-                                     size_t* out_data_items,
-                                     Atom* out_type);
+UI_EXPORT bool GetRawBytesOfProperty(
+    XID window,
+    Atom property,
+    scoped_refptr<base::RefCountedMemory>* out_data,
+    size_t* out_data_bytes,
+    size_t* out_data_items,
+    Atom* out_type);
 
 // Get the value of an int, int array, atom array or string property.  On
 // success, true is returned and the value is stored in |value|.
 //
 // TODO(erg): Once we remove the gtk port and are 100% aura, all of these
 // should accept an Atom instead of a string.
 UI_EXPORT bool GetIntProperty(XID window, const std::string& property_name,
                               int* value);
 UI_EXPORT bool GetXIDProperty(XID window, const std::string& property_name,
                               XID* value);
@@ skipping 141 matching lines @@
 // received.
 UI_EXPORT void UpdateButtonMap();
 
 // Initializes a XEvent that holds XKeyEvent for testing. Note that ui::EF_
 // flags should be passed as |flags|, not the native ones in <X11/X.h>.
 UI_EXPORT void InitXKeyEventForTesting(EventType type,
                                        KeyboardCode key_code,
                                        int flags,
                                        XEvent* event);
 
+// Manages a piece of X11 allocated memory as a RefCountedMemory segment. This
+// object takes ownership over the passed in memory and will free it with the
+// X11 allocator when done.
+class UI_EXPORT XRefcountedMemory : public base::RefCountedMemory {
+ public:
+  XRefcountedMemory(unsigned char* x11_data, size_t length)
+      : x11_data_(length ? x11_data : NULL),
+        length_(length) {
+  }
+
+  // Overridden from RefCountedMemory:
+  virtual const unsigned char* front() const OVERRIDE;
+  virtual size_t size() const OVERRIDE;
+
+ private:
+  virtual ~XRefcountedMemory();
+
+  unsigned char* x11_data_;
+  size_t length_;
+
+  DISALLOW_COPY_AND_ASSIGN(XRefcountedMemory);
+};
+
 // Keeps track of a string returned by an X function (e.g. XGetAtomName) and
 // makes sure it's XFree'd.
 class UI_EXPORT XScopedString {
  public:
   explicit XScopedString(char* str) : string_(str) {}
   ~XScopedString();
 
   const char* string() const { return string_; }
 
  private:
@@ skipping 39 matching lines @@
  private:
   ::Cursor cursor_;
   Display* display_;
 
   DISALLOW_COPY_AND_ASSIGN(XScopedCursor);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_X_X11_UTIL_H_