1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef UI_GFX_X_X11_ATOM_CACHE_H_
6#define UI_GFX_X_X11_ATOM_CACHE_H_
7
8#include <map>
9#include <string>
10
11#include "base/basictypes.h"
12#include "ui/gfx/gfx_export.h"
13#include "ui/gfx/x/x11_types.h"
14
15namespace ui {
16
17// Pre-caches all Atoms on first use to minimize roundtrips to the X11
18// server. By default, GetAtom() will CHECK() that atoms accessed through
19// GetAtom() were passed to the constructor, but this behaviour can be changed
20// with allow_uncached_atoms().
21class GFX_EXPORT X11AtomCache {
22 public:
23  // Preinterns the NULL terminated list of string |to_cache_ on |xdisplay|.
24  X11AtomCache(XDisplay* xdisplay, const char** to_cache);
25  ~X11AtomCache();
26
27  // Returns the pre-interned Atom without having to go to the x server.
28  XAtom GetAtom(const char*) const;
29
30  // When an Atom isn't in the list of items we've cached, we should look it
31  // up, cache it locally, and then return the result.
32  void allow_uncached_atoms() { uncached_atoms_allowed_ = true; }
33
34 private:
35  XDisplay* xdisplay_;
36
37  bool uncached_atoms_allowed_;
38
39  mutable std::map<std::string, XAtom> cached_atoms_;
40
41  DISALLOW_COPY_AND_ASSIGN(X11AtomCache);
42};
43
44}  // namespace ui
45
46#endif  // UI_GFX_X_X11_ATOM_CACHE_H_
47