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 UPDATE_ENGINE_PAYLOAD_GENERATOR_EXT2_FILESYSTEM_H_ 18 #define UPDATE_ENGINE_PAYLOAD_GENERATOR_EXT2_FILESYSTEM_H_ 19 20 #include "update_engine/payload_generator/filesystem_interface.h" 21 22 #include <memory> 23 #include <string> 24 #include <vector> 25 26 #include <ext2fs/ext2fs.h> 27 28 namespace chromeos_update_engine { 29 30 class Ext2Filesystem : public FilesystemInterface { 31 public: 32 // Creates an Ext2Filesystem from a ext2 formatted filesystem stored in a 33 // file. The file doesn't need to be loop-back mounted. 34 static std::unique_ptr<Ext2Filesystem> CreateFromFile( 35 const std::string& filename); 36 virtual ~Ext2Filesystem(); 37 38 // FilesystemInterface overrides. 39 size_t GetBlockSize() const override; 40 size_t GetBlockCount() const override; 41 42 // GetFiles will return one FilesystemInterface::File for every file and every 43 // directory in the filesystem. Hard-linked files will appear in the list 44 // several times with the same list of blocks. 45 // On addition to actual files, it also returns these pseudo-files: 46 // <free-space>: With all the unallocated data-blocks. 47 // <inode-blocks>: Will all the data-blocks for second and third level inodes 48 // of all the files. 49 // <group-descriptors>: With the block group descriptor and their reserved 50 // space. 51 // <metadata>: With the rest of ext2 metadata blocks, such as superblocks 52 // and bitmap tables. 53 bool GetFiles(std::vector<File>* files) const override; 54 55 bool LoadSettings(brillo::KeyValueStore* store) const override; 56 57 private: 58 Ext2Filesystem() = default; 59 60 // The ext2 main data structure holding the filesystem. 61 ext2_filsys filsys_ = nullptr; 62 63 // The file where the filesystem is stored. 64 std::string filename_; 65 66 DISALLOW_COPY_AND_ASSIGN(Ext2Filesystem); 67 }; 68 69 } // namespace chromeos_update_engine 70 71 #endif // UPDATE_ENGINE_PAYLOAD_GENERATOR_EXT2_FILESYSTEM_H_ 72