1 /*
2  * Copyright (C) 2015 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 #ifndef ANDROID_VOLD_EMULATED_VOLUME_H
18 #define ANDROID_VOLD_EMULATED_VOLUME_H
19 
20 #include "VolumeBase.h"
21 
22 #include <cutils/multiuser.h>
23 
24 namespace android {
25 namespace vold {
26 
27 /*
28  * Shared storage emulated on top of private storage.
29  *
30  * Knows how to spawn a FUSE daemon to synthesize permissions.  ObbVolume
31  * can be stacked above it.
32  *
33  * This volume is always multi-user aware, but is only binds itself to
34  * users when its primary storage.  This volume should never be presented
35  * as secondary storage, since we're strongly encouraging developers to
36  * store data local to their app.
37  */
38 class EmulatedVolume : public VolumeBase {
39   public:
40     explicit EmulatedVolume(const std::string& rawPath);
41     EmulatedVolume(const std::string& rawPath, dev_t device, const std::string& fsUuid);
42     virtual ~EmulatedVolume();
43 
44   protected:
45     status_t doMount() override;
46     status_t doUnmount() override;
47 
48   private:
49     std::string mRawPath;
50     std::string mLabel;
51 
52     std::string mFuseDefault;
53     std::string mFuseRead;
54     std::string mFuseWrite;
55     std::string mFuseFull;
56 
57     /* PID of FUSE wrapper */
58     pid_t mFusePid;
59 
60     DISALLOW_COPY_AND_ASSIGN(EmulatedVolume);
61 };
62 
63 }  // namespace vold
64 }  // namespace android
65 
66 #endif
67