Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/PIL/BufrStubImagePlugin.py: 69%

1# 

2# The Python Imaging Library 

3# $Id$ 

4# 

5# BUFR stub adapter 

6# 

7# Copyright (c) 1996-2003 by Fredrik Lundh 

8# 

9# See the README file for information on usage and redistribution. 

10# 

11from __future__ import annotations 

12 

13import os 

14 

15from . import Image, ImageFile 

16 

17TYPE_CHECKING = False 

18if TYPE_CHECKING: 

19 from typing import IO 

20 

21 

22def register_handler(handler: ImageFile.StubHandler | None) -> None: 

23 """ 

24 Install application-specific BUFR image handler. 

25 

26 :param handler: Handler object. 

27 """ 

28 BufrStubImageFile._handler = handler 

29 

30 

31# -------------------------------------------------------------------- 

32# Image adapter 

33 

34 

35def _accept(prefix: bytes) -> bool: 

36 return prefix.startswith((b"BUFR", b"ZCZC")) 

37 

38 

39class BufrStubImageFile(ImageFile.StubImageFile): 

40 format = "BUFR" 

41 format_description = "BUFR" 

42 

43 def _open(self) -> None: 

44 assert self.fp is not None 

45 if not _accept(self.fp.read(4)): 

46 msg = "Not a BUFR file" 

47 raise SyntaxError(msg) 

48 

49 self.fp.seek(-4, os.SEEK_CUR) 

50 

51 # make something up 

52 self._mode = "F" 

53 

54 

55def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None: 

56 if BufrStubImageFile._handler is None or not hasattr( 

57 BufrStubImageFile._handler, "save" 

58 ): 

59 msg = "BUFR save handler not installed" 

60 raise OSError(msg) 

61 BufrStubImageFile._handler.save(im, fp, filename) 

62 

63 

64# -------------------------------------------------------------------- 

65# Registry 

66 

67Image.register_open(BufrStubImageFile.format, BufrStubImageFile, _accept) 

68Image.register_save(BufrStubImageFile.format, _save) 

69 

70Image.register_extension(BufrStubImageFile.format, ".bufr")