1 /*
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef SYS_INSTALLER_MODULE_LOOP_H
17 #define SYS_INSTALLER_MODULE_LOOP_H
18 
19 #include <memory>
20 #include <string>
21 
22 #include "unique_fd.h"
23 
24 namespace OHOS {
25 namespace SysInstaller {
26 namespace Loop {
27 class LoopbackDeviceUniqueFd {
28 public:
29     UniqueFd deviceFd;
30     std::string name;
31 
LoopbackDeviceUniqueFd()32     LoopbackDeviceUniqueFd() {}
LoopbackDeviceUniqueFd(UniqueFd && fd,const std::string & name)33     LoopbackDeviceUniqueFd(UniqueFd &&fd, const std::string &name)
34         : deviceFd(std::move(fd)), name(name) {}
35 
LoopbackDeviceUniqueFd(LoopbackDeviceUniqueFd && fd)36     LoopbackDeviceUniqueFd(LoopbackDeviceUniqueFd &&fd) noexcept
37         : deviceFd(std::move(fd.deviceFd)), name(std::move(fd.name)) {}
38     LoopbackDeviceUniqueFd &operator=(LoopbackDeviceUniqueFd &&other) noexcept
39     {
40         MaybeCloseBad();
41         deviceFd = std::move(other.deviceFd);
42         name = std::move(other.name);
43         return *this;
44     }
45 
~LoopbackDeviceUniqueFd()46     ~LoopbackDeviceUniqueFd()
47     {
48         MaybeCloseBad();
49     }
50 
51     void MaybeCloseBad() const;
52 
CloseGood()53     void CloseGood()
54     {
55         deviceFd.Release();
56     }
57 
Get()58     int Get() const
59     {
60         return deviceFd.Get();
61     }
62 };
63 bool ConfigureReadAhead(const std::string &devicePath);
64 bool PreAllocateLoopDevices(const size_t num);
65 std::unique_ptr<LoopbackDeviceUniqueFd> CreateLoopDevice(
66     const std::string &target, const uint32_t imageOffset, const uint32_t imageSize);
67 bool RemoveDmLoopDevice(const std::string &mountPoint, const std::string &imagePath);
68 bool RemoveDmLoopDevice(const std::string &loopDevPath);
69 bool IsLoopDevMatchedImg(const std::string &loopPath, const std::string &imgFilePath);
70 bool CloseLoopDev(const std::string &loopPath);
71 bool ClearDmLoopDevice(const std::string &loopDevPath, const bool clearDm);
72 } // Loop
73 } // SysInstaller
74 } // namespace OHOS
75 #endif // SYS_INSTALLER_MODULE_LOOP_H