Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(542)

Side by Side Diff: mojo/application/public/cpp/app_lifetime_helper.h

Issue 1565343003: Move mojo/application/public -> mojo/shell/public (Closed) Base URL: https://chromium.googlesource.com/chromium/src.git@fetcher
Patch Set: . Created 4 years, 11 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View unified diff | Download patch
OLDNEW
(Empty)
1 // Copyright 2015 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 MOJO_APPLICATION_PUBLIC_CPP_APP_LIFETIME_HELPER_H_
6 #define MOJO_APPLICATION_PUBLIC_CPP_APP_LIFETIME_HELPER_H_
7
8 #include "base/macros.h"
9 #include "base/memory/scoped_ptr.h"
10 #include "base/single_thread_task_runner.h"
11
12 namespace mojo {
13
14 class ApplicationImpl;
15 class AppLifetimeHelper;
16
17 // A service implementation should keep this object as a member variable to hold
18 // a reference on the application.
19 // Since services can live on different threads than the app, this class is
20 // safe to use on any thread. However, each instance should only be used on one
21 // thread at a time (otherwise there'll be races between the addref resulting
22 // from cloning and destruction).
23 class AppRefCount {
24 public:
25 ~AppRefCount();
26
27 // When a service creates another object that is held by the client, it should
28 // also vend to it a refcount using this method. That way if the caller stops
29 // holding on to the service but keeps the reference to the object, the app is
30 // still alive.
31 scoped_ptr<AppRefCount> Clone();
32
33 private:
34 friend AppLifetimeHelper;
35
36 AppRefCount(AppLifetimeHelper* app_lifetime_helper,
37 scoped_refptr<base::SingleThreadTaskRunner> app_task_runner);
38
39 // Don't need to use weak ptr because if the app thread is alive that means
40 // app is.
41 AppLifetimeHelper* app_lifetime_helper_;
42 scoped_refptr<base::SingleThreadTaskRunner> app_task_runner_;
43
44 #ifndef NDEBUG
45 scoped_refptr<base::SingleThreadTaskRunner> clone_task_runner_;
46 #endif
47
48 DISALLOW_COPY_AND_ASSIGN(AppRefCount);
49 };
50
51 // This is a helper class for apps to manage their lifetime, specifically so
52 // apps can quit when they're not used anymore.
53 // An app can contain an object of this class as a member variable. Each time it
54 // creates an instance of a service, it gives it a refcount using
55 // CreateAppRefCount. The service implementation then keeps that object as a
56 // member variable. When all the service implemenations go away, the app will be
57 // quit with a call to mojo::ApplicationImpl::Terminate().
58 class AppLifetimeHelper {
59 public:
60 explicit AppLifetimeHelper(ApplicationImpl* app);
61 ~AppLifetimeHelper();
62
63 scoped_ptr<AppRefCount> CreateAppRefCount();
64
65 private:
66 friend AppRefCount;
67 void AddRef();
68 void Release();
69
70 friend ApplicationImpl;
71 void OnQuit();
72
73 ApplicationImpl* app_;
74 int ref_count_;
75
76 DISALLOW_COPY_AND_ASSIGN(AppLifetimeHelper);
77 };
78
79 } // namespace mojo
80
81 #endif // MOJO_APPLICATION_PUBLIC_CPP_APP_LIFETIME_HELPER_H_
OLDNEW
« no previous file with comments | « mojo/application/public/cpp/BUILD.gn ('k') | mojo/application/public/cpp/application_connection.h » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698