1 /* 2 * Copyright (C) 2019 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 #pragma once 18 19 #include <stdint.h> 20 21 #include <functional> 22 #include <memory> 23 #include <string> 24 #include <vector> 25 26 #include <android-base/unique_fd.h> 27 28 #include "fiemap_writer.h" 29 30 namespace android { 31 namespace fiemap_writer { 32 33 // Wrapper around FiemapWriter that is able to split images across files if 34 // necessary. 35 class SplitFiemap final { 36 public: 37 using ProgressCallback = std::function<bool(uint64_t, uint64_t)>; 38 39 // Create a new split fiemap file. If |max_piece_size| is 0, the number of 40 // pieces will be determined automatically by detecting the filesystem. 41 // Otherwise, the file will be split evenly (with the remainder in the 42 // final file). 43 static std::unique_ptr<SplitFiemap> Create(const std::string& file_path, uint64_t file_size, 44 uint64_t max_piece_size, 45 ProgressCallback progress = {}); 46 47 // Open an existing split fiemap file. 48 static std::unique_ptr<SplitFiemap> Open(const std::string& file_path); 49 50 ~SplitFiemap(); 51 52 // Return a list of all files created for a split file. 53 static bool GetSplitFileList(const std::string& file_path, std::vector<std::string>* list); 54 55 // Destroy all components of a split file. If the root file does not exist, 56 // this returns true and does not report an error. 57 static bool RemoveSplitFiles(const std::string& file_path, std::string* message = nullptr); 58 59 // Return whether all components of a split file still have pinned extents. 60 bool HasPinnedExtents() const; 61 62 // Helper method for writing data that spans files. Note there is no seek 63 // method (yet); this starts at 0 and increments the position by |bytes|. 64 bool Write(const void* data, uint64_t bytes); 65 66 // Flush all writes to all split files. 67 bool Flush(); 68 69 const std::vector<struct fiemap_extent>& extents(); 70 uint32_t block_size() const; size()71 uint64_t size() const { return total_size_; } 72 const std::string& bdev_path() const; 73 74 // Non-copyable & Non-movable 75 SplitFiemap(const SplitFiemap&) = delete; 76 SplitFiemap& operator=(const SplitFiemap&) = delete; 77 SplitFiemap& operator=(SplitFiemap&&) = delete; 78 SplitFiemap(SplitFiemap&&) = delete; 79 80 private: 81 SplitFiemap() = default; 82 void AddFile(FiemapUniquePtr&& file); 83 84 bool creating_ = false; 85 std::string list_file_; 86 std::vector<FiemapUniquePtr> files_; 87 std::vector<struct fiemap_extent> extents_; 88 uint64_t total_size_ = 0; 89 90 // Most recently open file and position for Write(). 91 size_t cursor_index_ = 0; 92 uint64_t cursor_file_pos_ = 0; 93 android::base::unique_fd cursor_fd_; 94 }; 95 96 } // namespace fiemap_writer 97 } // namespace android 98