1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LIBLP_UTILITY_H
#define LIBLP_UTILITY_H
#include <stddef.h>
#include <stdint.h>
#include <sys/types.h>
#include <limits>
#include <string>
#include <string_view>
#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include "liblp/liblp.h"
#define LP_TAG "[liblp]"
#define LWARN LOG(WARNING) << LP_TAG
#define LINFO LOG(INFO) << LP_TAG
#define LERROR LOG(ERROR) << LP_TAG
#define PWARNING PLOG(WARNING) << LP_TAG
#define PERROR PLOG(ERROR) << LP_TAG
namespace android {
namespace fs_mgr {
// Determine the size of a block device (or file). Logs and returns false on
// error. After calling this, the position of |fd| may have changed.
bool GetDescriptorSize(int fd, uint64_t* size);
// Return the offset of the primary or backup geometry.
int64_t GetPrimaryGeometryOffset();
int64_t GetBackupGeometryOffset();
// Return the offset of a primary metadata slot, relative to the start of the
// device.
int64_t GetPrimaryMetadataOffset(const LpMetadataGeometry& geometry, uint32_t slot_number);
// Return the offset of a backup metadata slot, relative to the end of the
// device.
int64_t GetBackupMetadataOffset(const LpMetadataGeometry& geometry, uint32_t slot_number);
// Return the total space at the start of the super partition that must be set
// aside from headers/metadata and backups.
uint64_t GetTotalMetadataSize(uint32_t metadata_max_size, uint32_t max_slots);
// Cross-platform helper for lseek64().
int64_t SeekFile64(int fd, int64_t offset, int whence);
// Compute a SHA256 hash.
void SHA256(const void* data, size_t length, uint8_t out[32]);
// Align |base| such that it is evenly divisible by |alignment|, which does not
// have to be a power of two. Return false on overflow.
template <typename T>
bool AlignTo(T base, uint32_t alignment, T* out) {
static_assert(std::numeric_limits<T>::is_integer);
static_assert(!std::numeric_limits<T>::is_signed);
if (!alignment) {
*out = base;
return true;
}
T remainder = base % alignment;
if (remainder == 0) {
*out = base;
return true;
}
T to_add = alignment - remainder;
if (to_add > std::numeric_limits<T>::max() - base) {
return false;
}
*out = base + to_add;
return true;
}
// Update names from C++ strings.
bool UpdateBlockDevicePartitionName(LpMetadataBlockDevice* device, const std::string& name);
bool UpdatePartitionGroupName(LpMetadataPartitionGroup* group, const std::string& name);
bool UpdatePartitionName(LpMetadataPartition* partition, const std::string& name);
// Call BLKROSET ioctl on fd so that fd is readonly / read-writable.
bool SetBlockReadonly(int fd, bool readonly);
::android::base::unique_fd GetControlFileOrOpen(std::string_view path, int flags);
// For Virtual A/B updates, modify |metadata| so that it can be written to |target_slot_number|.
bool UpdateMetadataForInPlaceSnapshot(LpMetadata* metadata, uint32_t source_slot_number,
uint32_t target_slot_number);
// Forcefully set metadata header version to 1.0, clearing any incompatible flags and attributes
// so that when downgrading to a build with liblp V0, the device still boots.
void SetMetadataHeaderV0(LpMetadata* metadata);
} // namespace fs_mgr
} // namespace android
#endif // LIBLP_UTILITY_H
|
