1// Copyright 2013 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 GIN_PUBLIC_ISOLATE_HOLDER_H_
6#define GIN_PUBLIC_ISOLATE_HOLDER_H_
7
8#include "base/basictypes.h"
9#include "base/memory/scoped_ptr.h"
10#include "gin/gin_export.h"
11#include "v8/include/v8.h"
12
13namespace gin {
14
15class PerIsolateData;
16class RunMicrotasksObserver;
17
18// To embed Gin, first initialize gin using IsolateHolder::Initialize and then
19// create an instance of IsolateHolder to hold the v8::Isolate in which you
20// will execute JavaScript. You might wish to subclass IsolateHolder if you
21// want to tie more state to the lifetime of the isolate.
22class GIN_EXPORT IsolateHolder {
23 public:
24  // Controls whether or not V8 should only accept strict mode scripts.
25  enum ScriptMode {
26    kNonStrictMode,
27    kStrictMode
28  };
29
30  IsolateHolder();
31  ~IsolateHolder();
32
33  // Should be invoked once before creating IsolateHolder instances to
34  // initialize V8 and Gin.
35  static void Initialize(ScriptMode mode,
36                         v8::ArrayBuffer::Allocator* allocator);
37
38  v8::Isolate* isolate() { return isolate_; }
39
40  // The implementations of Object.observe() and Promise enqueue v8 Microtasks
41  // that should be executed just before control is returned to the message
42  // loop. This method adds a MessageLoop TaskObserver which runs any pending
43  // Microtasks each time a Task is completed. This method should be called
44  // once, when a MessageLoop is created and it should be called on the
45  // MessageLoop's thread.
46  void AddRunMicrotasksObserver();
47
48  // This method should also only be called once, and on the MessageLoop's
49  // thread.
50  void RemoveRunMicrotasksObserver();
51
52 private:
53  v8::Isolate* isolate_;
54  scoped_ptr<PerIsolateData> isolate_data_;
55  scoped_ptr<RunMicrotasksObserver> task_observer_;
56
57  DISALLOW_COPY_AND_ASSIGN(IsolateHolder);
58};
59
60}  // namespace gin
61
62#endif  // GIN_PUBLIC_ISOLATE_HOLDER_H_
63