1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <stdint.h>
20 #include <sys/types.h>
21 
22 #include <android/gui/ISurfaceComposer.h>
23 #include <ui/DisplayId.h>
24 
25 #include <utils/Singleton.h>
26 #include <utils/StrongPointer.h>
27 
28 namespace android {
29 
30 // ---------------------------------------------------------------------------
31 
32 // ---------------------------------------------------------------------------
33 
34 // This holds our connection to the composer service (i.e. SurfaceFlinger).
35 // If the remote side goes away, we will re-establish the connection.
36 // Users of this class should not retain the value from
37 // getComposerService() for an extended period.
38 //
39 // (TODO: b/219785927, It's not clear that using Singleton is useful here anymore.)
40 class ComposerServiceAIDL : public Singleton<ComposerServiceAIDL> {
41     sp<gui::ISurfaceComposer> mComposerService;
42     sp<IBinder::DeathRecipient> mDeathObserver;
43     mutable std::mutex mMutex;
44 
45     ComposerServiceAIDL();
46     bool connectLocked();
47     void composerServiceDied();
48     friend class Singleton<ComposerServiceAIDL>;
49 
50 public:
51     // Get a connection to the Composer Service.  This will block until
52     // a connection is established. Returns null if permission is denied.
53     static sp<gui::ISurfaceComposer> getComposerService();
54 };
55 
56 // ---------------------------------------------------------------------------
57 }; // namespace android
58