#!/usr/bin/env python # SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD # SPDX-License-Identifier: Apache-2.0 import os from datetime import datetime from typing import Any, List, Optional from fatfs_utils.boot_sector import BootSector from fatfs_utils.fat import FAT from fatfs_utils.fatfs_state import FATFSState from fatfs_utils.fs_object import Directory from fatfs_utils.utils import (BYTES_PER_DIRECTORY_ENTRY, FATFS_INCEPTION, FATDefaults, get_args_for_partition_generator, read_filesystem) class FATFS: """ The class FATFS provides API for generating FAT file system. It contains reference to the FAT table and to the root directory. """ def __init__(self, binary_image_path: Optional[str] = None, size: int = FATDefaults.SIZE, reserved_sectors_cnt: int = FATDefaults.RESERVED_SECTORS_COUNT, fat_tables_cnt: int = FATDefaults.FAT_TABLES_COUNT, sectors_per_cluster: int = FATDefaults.SECTORS_PER_CLUSTER, sector_size: int = FATDefaults.SECTOR_SIZE, hidden_sectors: int = FATDefaults.HIDDEN_SECTORS, long_names_enabled: bool = False, use_default_datetime: bool = True, num_heads: int = FATDefaults.NUM_HEADS, oem_name: str = FATDefaults.OEM_NAME, sec_per_track: int = FATDefaults.SEC_PER_TRACK, volume_label: str = FATDefaults.VOLUME_LABEL, file_sys_type: str = FATDefaults.FILE_SYS_TYPE, root_entry_count: int = FATDefaults.ROOT_ENTRIES_COUNT, explicit_fat_type: int = None, media_type: int = FATDefaults.MEDIA_TYPE) -> None: # root directory bytes should be aligned by sector size assert (root_entry_count * BYTES_PER_DIRECTORY_ENTRY) % sector_size == 0 # number of bytes in the root dir must be even multiple of BPB_BytsPerSec assert ((root_entry_count * BYTES_PER_DIRECTORY_ENTRY) // sector_size) % 2 == 0 root_dir_sectors_cnt: int = (root_entry_count * BYTES_PER_DIRECTORY_ENTRY) // sector_size self.state: FATFSState = FATFSState(sector_size=sector_size, explicit_fat_type=explicit_fat_type, reserved_sectors_cnt=reserved_sectors_cnt, root_dir_sectors_cnt=root_dir_sectors_cnt, size=size, file_sys_type=file_sys_type, num_heads=num_heads, fat_tables_cnt=fat_tables_cnt, sectors_per_cluster=sectors_per_cluster, media_type=media_type, hidden_sectors=hidden_sectors, sec_per_track=sec_per_track, long_names_enabled=long_names_enabled, volume_label=volume_label, oem_name=oem_name, use_default_datetime=use_default_datetime) binary_image: bytes = bytearray( read_filesystem(binary_image_path) if binary_image_path else self.create_empty_fatfs()) self.state.binary_image = binary_image self.fat: FAT = FAT(boot_sector_state=self.state.boot_sector_state, init_=True) root_dir_size = self.state.boot_sector_state.root_dir_sectors_cnt * self.state.boot_sector_state.sector_size self.root_directory: Directory = Directory(name='A', # the name is not important, must be string size=root_dir_size, fat=self.fat, cluster=self.fat.clusters[1], fatfs_state=self.state) self.root_directory.init_directory() def create_file(self, name: str, extension: str = '', path_from_root: Optional[List[str]] = None, object_timestamp_: datetime = FATFS_INCEPTION) -> None: # when path_from_root is None the dir is root self.root_directory.new_file(name=name, extension=extension, path_from_root=path_from_root, object_timestamp_=object_timestamp_) def create_directory(self, name: str, path_from_root: Optional[List[str]] = None, object_timestamp_: datetime = FATFS_INCEPTION) -> None: # when path_from_root is None the dir is root parent_dir = self.root_directory if path_from_root: parent_dir = self.root_directory.recursive_search(path_from_root, self.root_directory) self.root_directory.new_directory(name=name, parent=parent_dir, path_from_root=path_from_root, object_timestamp_=object_timestamp_) def write_content(self, path_from_root: List[str], content: bytes) -> None: """ fat fs invokes root directory to recursively find the required file and writes the content """ self.root_directory.write_to_file(path_from_root, content) def create_empty_fatfs(self) -> Any: boot_sector_ = BootSector(boot_sector_state=self.state.boot_sector_state) boot_sector_.generate_boot_sector() return boot_sector_.binary_image def write_filesystem(self, output_path: str) -> None: with open(output_path, 'wb') as output: output.write(bytearray(self.state.binary_image)) def _generate_partition_from_folder(self, folder_relative_path: str, folder_path: str = '', is_dir: bool = False) -> None: """ Given path to folder and folder name recursively encodes folder into binary image. Used by method generate. """ real_path: str = os.path.join(folder_path, folder_relative_path) lower_path: str = folder_relative_path folder_relative_path = folder_relative_path.upper() normal_path = os.path.normpath(folder_relative_path) split_path = normal_path.split(os.sep) object_timestamp = datetime.fromtimestamp(os.path.getctime(real_path)) if os.path.isfile(real_path): with open(real_path, 'rb') as file: content = file.read() file_name, extension = os.path.splitext(split_path[-1]) extension = extension[1:] # remove the dot from the extension self.create_file(name=file_name, extension=extension, path_from_root=split_path[1:-1] or None, object_timestamp_=object_timestamp) self.write_content(split_path[1:], content) elif os.path.isdir(real_path): if not is_dir: self.create_directory(name=split_path[-1], path_from_root=split_path[1:-1], object_timestamp_=object_timestamp) # sorting files for better testability dir_content = list(sorted(os.listdir(real_path))) for path in dir_content: self._generate_partition_from_folder(os.path.join(lower_path, path), folder_path=folder_path) def generate(self, input_directory: str) -> None: """ Normalize path to folder and recursively encode folder to binary image """ path_to_folder, folder_name = os.path.split(input_directory) self._generate_partition_from_folder(folder_name, folder_path=path_to_folder, is_dir=True) def main() -> None: args = get_args_for_partition_generator('Create a FAT filesystem and populate it with directory content') if args.sector_size != 0x1000: raise NotImplementedError('The sector size not equal to 4096 is currently not supported for read-only mode!') fatfs = FATFS(sector_size=args.sector_size, sectors_per_cluster=args.sectors_per_cluster, size=args.partition_size, root_entry_count=args.root_entry_count, explicit_fat_type=args.fat_type, long_names_enabled=args.long_name_support, use_default_datetime=args.use_default_datetime) fatfs.generate(args.input_directory) fatfs.write_filesystem(args.output_file) if __name__ == '__main__': main()