# SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD # SPDX-License-Identifier: Apache-2.0 import os from typing import List, Optional, Tuple from .entry import Entry from .exceptions import FatalError, WriteDirectoryException from .fat import FAT, Cluster from .fatfs_state import FATFSState from .utils import required_clusters_count, split_content_into_sectors, split_to_name_and_extension class File: """ The class File provides API to write into the files. It represents file in the FS. """ ATTR_ARCHIVE = 0x20 ENTITY_TYPE = ATTR_ARCHIVE def __init__(self, name: str, fat: FAT, fatfs_state: FATFSState, entry: Entry, extension: str = '') -> None: self.name = name self.extension = extension self.fatfs_state = fatfs_state self.fat = fat self.size = 0 self._first_cluster = None self._entry = entry @property def entry(self) -> Entry: return self._entry @property def first_cluster(self) -> Optional[Cluster]: return self._first_cluster @first_cluster.setter def first_cluster(self, value: Cluster) -> None: self._first_cluster = value def name_equals(self, name: str, extension: str) -> bool: return self.name == name and self.extension == extension def write(self, content: bytes) -> None: self.entry.update_content_size(len(content)) # we assume that the correct amount of clusters is allocated current_cluster = self._first_cluster for content_part in split_content_into_sectors(content, self.fatfs_state.sector_size): content_as_list = content_part if current_cluster is None: raise FatalError('No free space left!') address = current_cluster.cluster_data_address self.fatfs_state.binary_image[address: address + len(content_part)] = content_as_list current_cluster = current_cluster.next_cluster class Directory: """ The Directory class provides API to add files and directories into the directory and to find the file according to path and write it. """ ATTR_DIRECTORY = 0x10 ATTR_ARCHIVE = 0x20 ENTITY_TYPE = ATTR_DIRECTORY def __init__(self, name, fat, fatfs_state, entry=None, cluster=None, size=None, extension='', parent=None): # type: (str, FAT, FATFSState, Optional[Entry], Cluster, Optional[int], str, Directory) -> None self.name = name self.fatfs_state = fatfs_state self.extension = extension self.fat = fat self.size = size or self.fatfs_state.sector_size # if directory is root its parent is itself self.parent: Directory = parent or self self._first_cluster = cluster # entries will be initialized after the cluster allocation self.entries: List[Entry] = [] self.entities = [] # type: ignore self._entry = entry # currently not in use (will use later for e.g. modification time, etc.) @property def is_root(self) -> bool: return self.parent is self @property def first_cluster(self) -> Cluster: return self._first_cluster @first_cluster.setter def first_cluster(self, value: Cluster) -> None: self._first_cluster = value def name_equals(self, name: str, extension: str) -> bool: return self.name == name and self.extension == extension def create_entries(self, cluster: Cluster) -> list: return [Entry(entry_id=i, parent_dir_entries_address=cluster.cluster_data_address, fatfs_state=self.fatfs_state) for i in range(self.size // self.fatfs_state.entry_size)] def init_directory(self) -> None: self.entries = self.create_entries(self._first_cluster) if not self.is_root: # the root directory doesn't contain link to itself nor the parent free_entry1 = self.find_free_entry() or self.chain_directory() free_entry1.allocate_entry(first_cluster_id=self.first_cluster.id, entity_name='.', entity_extension='', entity_type=self.ENTITY_TYPE) self.first_cluster = self._first_cluster free_entry2 = self.find_free_entry() or self.chain_directory() free_entry2.allocate_entry(first_cluster_id=self.parent.first_cluster.id, entity_name='..', entity_extension='', entity_type=self.parent.ENTITY_TYPE) self.parent.first_cluster = self.parent.first_cluster def lookup_entity(self, object_name: str, extension: str): # type: ignore for entity in self.entities: if entity.name == object_name and entity.extension == extension: return entity return None def recursive_search(self, path_as_list, current_dir): # type: ignore name, extension = split_to_name_and_extension(path_as_list[0]) next_obj = current_dir.lookup_entity(name, extension) if next_obj is None: raise FileNotFoundError('No such file or directory!') if len(path_as_list) == 1 and next_obj.name_equals(name, extension): return next_obj return self.recursive_search(path_as_list[1:], next_obj) def find_free_entry(self) -> Optional[Entry]: for entry in self.entries: if entry.is_empty: return entry return None def _extend_directory(self) -> None: current = self.first_cluster while current.next_cluster is not None: current = current.next_cluster new_cluster = self.fat.find_free_cluster() current.set_in_fat(new_cluster.id) current.next_cluster = new_cluster self.entries += self.create_entries(new_cluster) def chain_directory(self) -> Entry: self._extend_directory() free_entry = self.find_free_entry() if free_entry is None: raise FatalError('No more space left!') return free_entry def allocate_object(self, name, entity_type, path_from_root=None, extension=''): # type: (str, int, Optional[List[str]], str) -> Tuple[Cluster, Entry, Directory] """ Method finds the target directory in the path and allocates cluster (both the record in FAT and cluster in the data region) and entry in the specified directory """ free_cluster = self.fat.find_free_cluster() target_dir = self if not path_from_root else self.recursive_search(path_from_root, self) free_entry = target_dir.find_free_entry() or target_dir.chain_directory() free_entry.allocate_entry(first_cluster_id=free_cluster.id, entity_name=name, entity_extension=extension, entity_type=entity_type) return free_cluster, free_entry, target_dir def new_file(self, name: str, extension: str, path_from_root: Optional[List[str]]) -> None: free_cluster, free_entry, target_dir = self.allocate_object(name=name, extension=extension, entity_type=Directory.ATTR_ARCHIVE, path_from_root=path_from_root) file = File(name, fat=self.fat, extension=extension, fatfs_state=self.fatfs_state, entry=free_entry) file.first_cluster = free_cluster target_dir.entities.append(file) def new_directory(self, name, parent, path_from_root): # type: (str, Directory, Optional[List[str]]) -> None free_cluster, free_entry, target_dir = self.allocate_object(name=name, entity_type=Directory.ATTR_DIRECTORY, path_from_root=path_from_root) directory = Directory(name=name, fat=self.fat, parent=parent, fatfs_state=self.fatfs_state, entry=free_entry) directory.first_cluster = free_cluster directory.init_directory() target_dir.entities.append(directory) def write_to_file(self, path: List[str], content: bytes) -> None: """ Writes to file existing in the directory structure. :param path: path split into the list :param content: content as a string to be written into a file :returns: None :raises WriteDirectoryException: raised is the target object for writing is a directory """ entity_to_write = self.recursive_search(path, self) if isinstance(entity_to_write, File): clusters_cnt = required_clusters_count(cluster_size=self.fatfs_state.sector_size, content=content) self.fat.allocate_chain(entity_to_write.first_cluster, clusters_cnt) entity_to_write.write(content) else: raise WriteDirectoryException(f'`{os.path.join(*path)}` is a directory!')