Adam Lesinski | 16c4d15 | 2014-01-24 13:27:13 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2009 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 _UTILS_BACKUP_HELPERS_H |
| 18 | #define _UTILS_BACKUP_HELPERS_H |
| 19 | |
Christopher Tate | 11ae768 | 2015-03-24 18:48:10 -0700 | [diff] [blame] | 20 | #include <sys/stat.h> |
| 21 | |
Adam Lesinski | 16c4d15 | 2014-01-24 13:27:13 -0800 | [diff] [blame] | 22 | #include <utils/Errors.h> |
| 23 | #include <utils/String8.h> |
| 24 | #include <utils/KeyedVector.h> |
| 25 | |
| 26 | namespace android { |
| 27 | |
| 28 | enum { |
| 29 | BACKUP_HEADER_ENTITY_V1 = 0x61746144, // Data (little endian) |
| 30 | }; |
| 31 | |
| 32 | typedef struct { |
| 33 | int type; // BACKUP_HEADER_ENTITY_V1 |
| 34 | int keyLen; // length of the key name, not including the null terminator |
| 35 | int dataSize; // size of the data, not including the padding, -1 means delete |
| 36 | } entity_header_v1; |
| 37 | |
| 38 | struct SnapshotHeader { |
| 39 | int magic0; |
| 40 | int fileCount; |
| 41 | int magic1; |
| 42 | int totalSize; |
| 43 | }; |
| 44 | |
| 45 | struct FileState { |
| 46 | int modTime_sec; |
| 47 | int modTime_nsec; |
| 48 | int mode; |
| 49 | int size; |
| 50 | int crc32; |
| 51 | int nameLen; |
| 52 | }; |
| 53 | |
| 54 | struct FileRec { |
| 55 | String8 file; |
| 56 | bool deleted; |
| 57 | FileState s; |
| 58 | }; |
| 59 | |
| 60 | |
| 61 | /** |
| 62 | * Writes the data. |
| 63 | * |
| 64 | * If an error occurs, it poisons this object and all write calls will fail |
| 65 | * with the error that occurred. |
| 66 | */ |
| 67 | class BackupDataWriter |
| 68 | { |
| 69 | public: |
| 70 | BackupDataWriter(int fd); |
| 71 | // does not close fd |
| 72 | ~BackupDataWriter(); |
| 73 | |
| 74 | status_t WriteEntityHeader(const String8& key, size_t dataSize); |
| 75 | |
| 76 | /* Note: WriteEntityData will write arbitrary data into the file without |
| 77 | * validation or a previously-supplied header. The full backup implementation |
| 78 | * uses it this way to generate a controlled binary stream that is not |
| 79 | * entity-structured. If the implementation here is changed, either this |
| 80 | * use case must remain valid, or the full backup implementation should be |
| 81 | * adjusted to use some other appropriate mechanism. |
| 82 | */ |
| 83 | status_t WriteEntityData(const void* data, size_t size); |
| 84 | |
| 85 | void SetKeyPrefix(const String8& keyPrefix); |
| 86 | |
| 87 | private: |
| 88 | explicit BackupDataWriter(); |
| 89 | status_t write_padding_for(int n); |
| 90 | |
| 91 | int m_fd; |
| 92 | status_t m_status; |
| 93 | ssize_t m_pos; |
| 94 | int m_entityCount; |
| 95 | String8 m_keyPrefix; |
| 96 | }; |
| 97 | |
| 98 | /** |
| 99 | * Reads the data. |
| 100 | * |
| 101 | * If an error occurs, it poisons this object and all write calls will fail |
| 102 | * with the error that occurred. |
| 103 | */ |
| 104 | class BackupDataReader |
| 105 | { |
| 106 | public: |
| 107 | BackupDataReader(int fd); |
| 108 | // does not close fd |
| 109 | ~BackupDataReader(); |
| 110 | |
| 111 | status_t Status(); |
| 112 | status_t ReadNextHeader(bool* done, int* type); |
| 113 | |
| 114 | bool HasEntities(); |
| 115 | status_t ReadEntityHeader(String8* key, size_t* dataSize); |
| 116 | status_t SkipEntityData(); // must be called with the pointer at the beginning of the data. |
| 117 | ssize_t ReadEntityData(void* data, size_t size); |
| 118 | |
| 119 | private: |
| 120 | explicit BackupDataReader(); |
| 121 | status_t skip_padding(); |
| 122 | |
| 123 | int m_fd; |
| 124 | bool m_done; |
| 125 | status_t m_status; |
| 126 | ssize_t m_pos; |
| 127 | ssize_t m_dataEndPos; |
| 128 | int m_entityCount; |
| 129 | union { |
| 130 | int type; |
| 131 | entity_header_v1 entity; |
| 132 | } m_header; |
| 133 | String8 m_key; |
| 134 | }; |
| 135 | |
| 136 | int back_up_files(int oldSnapshotFD, BackupDataWriter* dataStream, int newSnapshotFD, |
| 137 | char const* const* files, char const* const *keys, int fileCount); |
| 138 | |
| 139 | int write_tarfile(const String8& packageName, const String8& domain, |
Christopher Tate | 11ae768 | 2015-03-24 18:48:10 -0700 | [diff] [blame] | 140 | const String8& rootPath, const String8& filePath, off_t* outSize, |
| 141 | BackupDataWriter* outputStream); |
Adam Lesinski | 16c4d15 | 2014-01-24 13:27:13 -0800 | [diff] [blame] | 142 | |
| 143 | class RestoreHelperBase |
| 144 | { |
| 145 | public: |
| 146 | RestoreHelperBase(); |
| 147 | ~RestoreHelperBase(); |
| 148 | |
| 149 | status_t WriteFile(const String8& filename, BackupDataReader* in); |
| 150 | status_t WriteSnapshot(int fd); |
| 151 | |
| 152 | private: |
| 153 | void* m_buf; |
| 154 | bool m_loggedUnknownMetadata; |
| 155 | KeyedVector<String8,FileRec> m_files; |
| 156 | }; |
| 157 | |
Christopher Tate | 43a4a8c | 2015-01-08 18:42:33 -0800 | [diff] [blame] | 158 | //#define TEST_BACKUP_HELPERS 1 |
Adam Lesinski | 16c4d15 | 2014-01-24 13:27:13 -0800 | [diff] [blame] | 159 | |
| 160 | #if TEST_BACKUP_HELPERS |
| 161 | int backup_helper_test_empty(); |
| 162 | int backup_helper_test_four(); |
| 163 | int backup_helper_test_files(); |
| 164 | int backup_helper_test_null_base(); |
| 165 | int backup_helper_test_missing_file(); |
| 166 | int backup_helper_test_data_writer(); |
| 167 | int backup_helper_test_data_reader(); |
| 168 | #endif |
| 169 | |
| 170 | } // namespace android |
| 171 | |
| 172 | #endif // _UTILS_BACKUP_HELPERS_H |