Home | History | Annotate | Download | only in payload_generator
      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 #if defined(__clang__)
     27 // TODO: Remove these pragmas when b/35721782 is fixed.
     28 #pragma clang diagnostic push
     29 #pragma clang diagnostic ignored "-Wmacro-redefined"
     30 #endif
     31 #include <ext2fs/ext2fs.h>
     32 #if defined(__clang__)
     33 #pragma clang diagnostic pop
     34 #endif
     35 
     36 namespace chromeos_update_engine {
     37 
     38 class Ext2Filesystem : public FilesystemInterface {
     39  public:
     40   // Creates an Ext2Filesystem from a ext2 formatted filesystem stored in a
     41   // file. The file doesn't need to be loop-back mounted.
     42   static std::unique_ptr<Ext2Filesystem> CreateFromFile(
     43       const std::string& filename);
     44   virtual ~Ext2Filesystem();
     45 
     46   // FilesystemInterface overrides.
     47   size_t GetBlockSize() const override;
     48   size_t GetBlockCount() const override;
     49 
     50   // GetFiles will return one FilesystemInterface::File for every file and every
     51   // directory in the filesystem. Hard-linked files will appear in the list
     52   // several times with the same list of blocks.
     53   // On addition to actual files, it also returns these pseudo-files:
     54   //  <free-space>: With all the unallocated data-blocks.
     55   //  <inode-blocks>: Will all the data-blocks for second and third level inodes
     56   //    of all the files.
     57   //  <group-descriptors>: With the block group descriptor and their reserved
     58   //    space.
     59   //  <metadata>: With the rest of ext2 metadata blocks, such as superblocks
     60   //    and bitmap tables.
     61   bool GetFiles(std::vector<File>* files) const override;
     62 
     63   bool LoadSettings(brillo::KeyValueStore* store) const override;
     64 
     65  private:
     66   Ext2Filesystem() = default;
     67 
     68   // The ext2 main data structure holding the filesystem.
     69   ext2_filsys filsys_ = nullptr;
     70 
     71   // The file where the filesystem is stored.
     72   std::string filename_;
     73 
     74   DISALLOW_COPY_AND_ASSIGN(Ext2Filesystem);
     75 };
     76 
     77 }  // namespace chromeos_update_engine
     78 
     79 #endif  // UPDATE_ENGINE_PAYLOAD_GENERATOR_EXT2_FILESYSTEM_H_
     80