def test_open_code(self): # Check that the default behaviour of open_code matches # open("rb") with self.FileIO(__file__, "rb") as f: expected = f.read() with _io.open_code(__file__) as f: actual = f.read() self.assertEqual(expected, actual)
def _get_data(archive, toc_entry): datapath, compress, data_size, file_size, file_offset, time, date, crc = toc_entry if data_size < 0: raise ZipImportError('negative data size') with _io.open_code(archive) as fp: # Check to make sure the local file header is correct try: fp.seek(file_offset) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) buffer = fp.read(30) if len(buffer) != 30: raise EOFError('EOF read where not expected') if buffer[:4] != b'PK\x03\x04': # Bad: Local File Header raise ZipImportError(f'bad local file header: {archive!r}', path=archive) name_size = _unpack_uint16(buffer[26:28]) extra_size = _unpack_uint16(buffer[28:30]) header_size = 30 + name_size + extra_size file_offset += header_size # Start of file data try: fp.seek(file_offset) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) raw_data = fp.read(data_size) if len(raw_data) != data_size: raise OSError("zipimport: can't read data") if compress == 0: # data is not compressed return raw_data # Decompress with zlib try: decompress = _get_decompress_func() except Exception: raise ZipImportError("can't decompress data; zlib not available") return decompress(raw_data, -15)
def _read_directory(archive): try: fp = _io.open_code(archive) except OSError: raise ZipImportError(f"can't open Zip file: {archive!r}", path=archive) with fp: try: fp.seek(-END_CENTRAL_DIR_SIZE, 2) header_position = fp.tell() buffer = fp.read(END_CENTRAL_DIR_SIZE) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) if len(buffer) != END_CENTRAL_DIR_SIZE: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) if buffer[:4] != STRING_END_ARCHIVE: # Bad: End of Central Dir signature # Check if there's a comment. try: fp.seek(0, 2) file_size = fp.tell() except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) max_comment_start = max( file_size - MAX_COMMENT_LEN - END_CENTRAL_DIR_SIZE, 0) try: fp.seek(max_comment_start) data = fp.read() except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) pos = data.rfind(STRING_END_ARCHIVE) if pos < 0: raise ZipImportError(f'not a Zip file: {archive!r}', path=archive) buffer = data[pos:pos + END_CENTRAL_DIR_SIZE] if len(buffer) != END_CENTRAL_DIR_SIZE: raise ZipImportError(f"corrupt Zip file: {archive!r}", path=archive) header_position = file_size - len(data) + pos header_size = _unpack_uint32(buffer[12:16]) header_offset = _unpack_uint32(buffer[16:20]) if header_position < header_size: raise ZipImportError(f'bad central directory size: {archive!r}', path=archive) if header_position < header_offset: raise ZipImportError(f'bad central directory offset: {archive!r}', path=archive) header_position -= header_size arc_offset = header_position - header_offset if arc_offset < 0: raise ZipImportError( f'bad central directory size or offset: {archive!r}', path=archive) files = {} # Start of Central Directory count = 0 try: fp.seek(header_position) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) while True: buffer = fp.read(46) if len(buffer) < 4: raise EOFError('EOF read where not expected') # Start of file header if buffer[:4] != b'PK\x01\x02': break # Bad: Central Dir File Header if len(buffer) != 46: raise EOFError('EOF read where not expected') flags = _unpack_uint16(buffer[8:10]) compress = _unpack_uint16(buffer[10:12]) time = _unpack_uint16(buffer[12:14]) date = _unpack_uint16(buffer[14:16]) crc = _unpack_uint32(buffer[16:20]) data_size = _unpack_uint32(buffer[20:24]) file_size = _unpack_uint32(buffer[24:28]) name_size = _unpack_uint16(buffer[28:30]) extra_size = _unpack_uint16(buffer[30:32]) comment_size = _unpack_uint16(buffer[32:34]) file_offset = _unpack_uint32(buffer[42:46]) header_size = name_size + extra_size + comment_size if file_offset > header_offset: raise ZipImportError(f'bad local header offset: {archive!r}', path=archive) file_offset += arc_offset try: name = fp.read(name_size) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) if len(name) != name_size: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) # On Windows, calling fseek to skip over the fields we don't use is # slower than reading the data because fseek flushes stdio's # internal buffers. See issue #8745. try: if len(fp.read(header_size - name_size)) != header_size - name_size: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) except OSError: raise ZipImportError(f"can't read Zip file: {archive!r}", path=archive) if flags & 0x800: # UTF-8 file names extension name = name.decode() else: # Historical ZIP filename encoding try: name = name.decode('ascii') except UnicodeDecodeError: name = name.decode('latin1').translate(cp437_table) name = name.replace('/', path_sep) path = _bootstrap_external._path_join(archive, name) t = (path, compress, data_size, file_size, file_offset, time, date, crc) files[name] = t count += 1 _bootstrap._verbose_message('zipimport: found {} names in {!r}', count, archive) return files