1 /*
2  * Copyright (C) 2020 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 <memory>
20 
21 #include <utils/Errors.h>
22 #include <vintf/Dirmap.h>
23 #include <vintf/FileSystem.h>
24 
25 namespace android::vintf::details {
26 
27 // A FileSystem object that uses Dirmap to redirect reads.
28 // FileSystem is read via the internal impl.
29 class HostFileSystem : public FileSystemImpl {
30    public:
31     // Use FileSystemImpl for any actual reads.
32     HostFileSystem(const Dirmap& dirmap, status_t missingError);
33     // Use |impl| for any actual reads. Does not own impl.
34     HostFileSystem(const Dirmap& dirmap, status_t missingError, FileSystem* impl);
35     // Use |impl| for any actual reads. Owns impl.
36     HostFileSystem(const Dirmap& dirmap, status_t missingError, std::unique_ptr<FileSystem>&& impl);
37 
38     status_t fetch(const std::string& path, std::string* fetched,
39                    std::string* error) const override;
40 
41     status_t listFiles(const std::string& path, std::vector<std::string>* out,
42                        std::string* error) const override;
43 
44    private:
45     std::string resolve(const std::string& path, std::string* error) const;
46 
47     Dirmap mDirMap;
48     status_t mMissingError;
49 
50     std::unique_ptr<FileSystem> mImplUniq;
51     FileSystem* mImpl;
52 };
53 
54 }  // namespace android::vintf::details
55