# SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD # SPDX-License-Identifier: Apache-2.0 from typing import List, Optional, Union from construct import Const, Int8ul, Int16ul, Int32ul, PaddedString, Struct from .exceptions import LowerCaseException, TooLongNameException from .fatfs_state import FATFSState from .utils import (DATETIME, EMPTY_BYTE, FATFS_INCEPTION, MAX_EXT_SIZE, MAX_NAME_SIZE, SHORT_NAMES_ENCODING, FATDefaults, build_date_entry, build_time_entry, is_valid_fatfs_name, pad_string) class Entry: """ The class Entry represents entry of the directory. """ ATTR_READ_ONLY: int = 0x01 ATTR_HIDDEN: int = 0x02 ATTR_SYSTEM: int = 0x04 ATTR_VOLUME_ID: int = 0x08 ATTR_DIRECTORY: int = 0x10 # directory ATTR_ARCHIVE: int = 0x20 # file ATTR_LONG_NAME: int = ATTR_READ_ONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME_ID # indexes in the entry structure and sizes in bytes, not in characters (encoded using 2 bytes for lfn) LDIR_Name1_IDX: int = 1 LDIR_Name1_SIZE: int = 5 LDIR_Name2_IDX: int = 14 LDIR_Name2_SIZE: int = 6 LDIR_Name3_IDX: int = 28 LDIR_Name3_SIZE: int = 2 # one entry can hold 13 characters with size 2 bytes distributed in three regions of the 32 bytes entry CHARS_PER_ENTRY: int = LDIR_Name1_SIZE + LDIR_Name2_SIZE + LDIR_Name3_SIZE # the last 16 bytes record in the LFN entry has first byte masked with the following value LAST_RECORD_LFN_ENTRY: int = 0x40 SHORT_ENTRY: int = -1 # this value is used for short-like entry but with accepted lower case SHORT_ENTRY_LN: int = 0 # The 1st January 1980 00:00:00 DEFAULT_DATE: DATETIME = (FATFS_INCEPTION.year, FATFS_INCEPTION.month, FATFS_INCEPTION.day) DEFAULT_TIME: DATETIME = (FATFS_INCEPTION.hour, FATFS_INCEPTION.minute, FATFS_INCEPTION.second) ENTRY_FORMAT_SHORT_NAME = Struct( 'DIR_Name' / PaddedString(MAX_NAME_SIZE, SHORT_NAMES_ENCODING), 'DIR_Name_ext' / PaddedString(MAX_EXT_SIZE, SHORT_NAMES_ENCODING), 'DIR_Attr' / Int8ul, 'DIR_NTRes' / Int8ul, # this tagged for lfn (0x00 for lfn prefix, 0x18 for short name in lfn) 'DIR_CrtTimeTenth' / Const(EMPTY_BYTE), # ignored by esp-idf fatfs library 'DIR_CrtTime' / Int16ul, # ignored by esp-idf fatfs library 'DIR_CrtDate' / Int16ul, # ignored by esp-idf fatfs library 'DIR_LstAccDate' / Int16ul, # must be same as DIR_WrtDate 'DIR_FstClusHI' / Const(2 * EMPTY_BYTE), 'DIR_WrtTime' / Int16ul, 'DIR_WrtDate' / Int16ul, 'DIR_FstClusLO' / Int16ul, 'DIR_FileSize' / Int32ul, ) def __init__(self, entry_id: int, parent_dir_entries_address: int, fatfs_state: FATFSState) -> None: self.fatfs_state: FATFSState = fatfs_state self.id: int = entry_id self.entry_address: int = parent_dir_entries_address + self.id * FATDefaults.ENTRY_SIZE self._is_alias: bool = False self._is_empty: bool = True @staticmethod def get_cluster_id(obj_: dict) -> int: cluster_id_: int = obj_['DIR_FstClusLO'] return cluster_id_ @property def is_empty(self) -> bool: return self._is_empty @staticmethod def _parse_entry(entry_bytearray: Union[bytearray, bytes]) -> dict: entry_: dict = Entry.ENTRY_FORMAT_SHORT_NAME.parse(entry_bytearray) return entry_ @staticmethod def _build_entry(**kwargs) -> bytes: # type: ignore entry_: bytes = Entry.ENTRY_FORMAT_SHORT_NAME.build(dict(**kwargs)) return entry_ @staticmethod def _build_entry_long(names: List[bytes], checksum: int, order: int, is_last: bool) -> bytes: """ Long entry starts with 1 bytes of the order, if the entry is the last in the chain it is or-masked with 0x40, otherwise is without change (or masked with 0x00). The following example shows 3 entries: first two (0x2000-0x2040) are long in the reverse order and the last one (0x2040-0x2060) is short. The entries define file name "thisisverylongfilenama.txt". 00002000: 42 67 00 66 00 69 00 6C 00 65 00 0F 00 43 6E 00 Bg.f.i.l.e...Cn. 00002010: 61 00 6D 00 61 00 2E 00 74 00 00 00 78 00 74 00 a.m.a...t...x.t. 00002020: 01 74 00 68 00 69 00 73 00 69 00 0F 00 43 73 00 .t.h.i.s.i...Cs. 00002030: 76 00 65 00 72 00 79 00 6C 00 00 00 6F 00 6E 00 v.e.r.y.l...o.n. 00002040: 54 48 49 53 49 53 7E 31 54 58 54 20 00 00 00 00 THISIS~1TXT..... 00002050: 21 00 00 00 00 00 00 00 21 00 02 00 15 00 00 00 !.......!....... """ order |= (Entry.LAST_RECORD_LFN_ENTRY if is_last else 0x00) long_entry: bytes = (Int8ul.build(order) + # order of the long name entry (possibly masked with 0x40) names[0] + # first 5 characters (10 bytes) of the name part Int8ul.build(Entry.ATTR_LONG_NAME) + # one byte entity type ATTR_LONG_NAME Int8ul.build(0) + # one byte of zeros Int8ul.build(checksum) + # lfn_checksum defined in utils.py names[1] + # next 6 characters (12 bytes) of the name part Int16ul.build(0) + # 2 bytes of zeros names[2]) # last 2 characters (4 bytes) of the name part return long_entry @staticmethod def parse_entry_long(entry_bytes_: bytes, my_check: int) -> dict: order_ = Int8ul.parse(entry_bytes_[0:1]) names0 = entry_bytes_[1:11] if Int8ul.parse(entry_bytes_[12:13]) != 0 or Int16ul.parse(entry_bytes_[26:28]) != 0 or Int8ul.parse(entry_bytes_[11:12]) != 15: return {} if Int8ul.parse(entry_bytes_[13:14]) != my_check: return {} names1 = entry_bytes_[14:26] names2 = entry_bytes_[28:32] return { 'order': order_, 'name1': names0, 'name2': names1, 'name3': names2, 'is_last': bool(order_ & Entry.LAST_RECORD_LFN_ENTRY == Entry.LAST_RECORD_LFN_ENTRY) } @property def entry_bytes(self) -> bytes: """ :returns: Bytes defining the entry belonging to the given instance. """ start_: int = self.entry_address entry_: bytes = self.fatfs_state.binary_image[start_: start_ + FATDefaults.ENTRY_SIZE] return entry_ @entry_bytes.setter def entry_bytes(self, value: bytes) -> None: """ :param value: new content of the entry :returns: None The setter sets the content of the entry in bytes. """ self.fatfs_state.binary_image[self.entry_address: self.entry_address + FATDefaults.ENTRY_SIZE] = value def _clean_entry(self) -> None: self.entry_bytes: bytes = FATDefaults.ENTRY_SIZE * EMPTY_BYTE def allocate_entry(self, first_cluster_id: int, entity_name: str, entity_type: int, entity_extension: str = '', size: int = 0, date: DATETIME = DEFAULT_DATE, time: DATETIME = DEFAULT_TIME, lfn_order: int = SHORT_ENTRY, lfn_names: Optional[List[bytes]] = None, lfn_checksum_: int = 0, fits_short: bool = False, lfn_is_last: bool = False) -> None: """ :param first_cluster_id: id of the first data cluster for given entry :param entity_name: name recorded in the entry :param entity_extension: extension recorded in the entry :param size: size of the content of the file :param date: denotes year (actual year minus 1980), month number day of the month (minimal valid is (0, 1, 1)) :param time: denotes hour, minute and second with granularity 2 seconds (sec // 2) :param entity_type: type of the entity (file [0x20] or directory [0x10]) :param lfn_order: if long names support is enabled, defines order in long names entries sequence (-1 for short) :param lfn_names: if the entry is dedicated for long names the lfn_names contains LDIR_Name1, LDIR_Name2 and LDIR_Name3 in this order :param lfn_checksum_: use only for long file names, checksum calculated lfn_checksum function :param fits_short: determines if the name fits in 8.3 filename :param lfn_is_last: determines if the long file name entry is holds last part of the name, thus its address is first in the physical order :returns: None :raises LowerCaseException: In case when long_names_enabled is set to False and filename exceeds 8 chars for name or 3 chars for extension the exception is raised :raises TooLongNameException: When long_names_enabled is set to False and name doesn't fit to 8.3 filename an exception is raised """ valid_full_name: bool = is_valid_fatfs_name(entity_name) and is_valid_fatfs_name(entity_extension) if not (valid_full_name or lfn_order >= 0): raise LowerCaseException('Lower case is not supported in short name entry, use upper case.') if self.fatfs_state.use_default_datetime: date = self.DEFAULT_DATE time = self.DEFAULT_TIME # clean entry before allocation self._clean_entry() self._is_empty = False object_name = entity_name.upper() if not self.fatfs_state.long_names_enabled else entity_name object_extension = entity_extension.upper() if not self.fatfs_state.long_names_enabled else entity_extension exceeds_short_name: bool = len(object_name) > MAX_NAME_SIZE or len(object_extension) > MAX_EXT_SIZE if not self.fatfs_state.long_names_enabled and exceeds_short_name: raise TooLongNameException( 'Maximal length of the object name is {} characters and {} characters for extension!'.format( MAX_NAME_SIZE, MAX_EXT_SIZE ) ) start_address = self.entry_address end_address = start_address + FATDefaults.ENTRY_SIZE if lfn_order in (self.SHORT_ENTRY, self.SHORT_ENTRY_LN): date_entry_: int = build_date_entry(*date) time_entry: int = build_time_entry(*time) self.fatfs_state.binary_image[start_address: end_address] = self._build_entry( DIR_Name=pad_string(object_name, size=MAX_NAME_SIZE), DIR_Name_ext=pad_string(object_extension, size=MAX_EXT_SIZE), DIR_Attr=entity_type, DIR_NTRes=0x00 if (not self.fatfs_state.long_names_enabled) or (not fits_short) else 0x18, DIR_FstClusLO=first_cluster_id, DIR_FileSize=size, DIR_CrtDate=date_entry_, # ignored by esp-idf fatfs library DIR_LstAccDate=date_entry_, # must be same as DIR_WrtDate DIR_WrtDate=date_entry_, DIR_CrtTime=time_entry, # ignored by esp-idf fatfs library DIR_WrtTime=time_entry ) else: assert lfn_names is not None self.fatfs_state.binary_image[start_address: end_address] = self._build_entry_long(lfn_names, lfn_checksum_, lfn_order, lfn_is_last) def update_content_size(self, content_size: int) -> None: """ :param content_size: the new size of the file content in bytes :returns: None This method parses the binary entry to the construct structure, updates the content size of the file and builds new binary entry. """ parsed_entry = self._parse_entry(self.entry_bytes) parsed_entry.DIR_FileSize = content_size # type: ignore self.entry_bytes = Entry.ENTRY_FORMAT_SHORT_NAME.build(parsed_entry)