Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/pillow-10.4.0-py3.8-linux-x86_64.egg/PIL/BufrStubImagePlugin.py: 50%

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 

13from typing import IO 

14 

15from . import Image, ImageFile 

16 

17_handler = None 

18 

19 

20def register_handler(handler: ImageFile.StubHandler | None) -> None: 

21 """ 

22 Install application-specific BUFR image handler. 

23 

24 :param handler: Handler object. 

25 """ 

26 global _handler 

27 _handler = handler 

28 

29 

30# -------------------------------------------------------------------- 

31# Image adapter 

32 

33 

34def _accept(prefix: bytes) -> bool: 

35 return prefix[:4] == b"BUFR" or prefix[:4] == b"ZCZC" 

36 

37 

38class BufrStubImageFile(ImageFile.StubImageFile): 

39 format = "BUFR" 

40 format_description = "BUFR" 

41 

42 def _open(self) -> None: 

43 offset = self.fp.tell() 

44 

45 if not _accept(self.fp.read(4)): 

46 msg = "Not a BUFR file" 

47 raise SyntaxError(msg) 

48 

49 self.fp.seek(offset) 

50 

51 # make something up 

52 self._mode = "F" 

53 self._size = 1, 1 

54 

55 loader = self._load() 

56 if loader: 

57 loader.open(self) 

58 

59 def _load(self) -> ImageFile.StubHandler | None: 

60 return _handler 

61 

62 

63def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None: 

64 if _handler is None or not hasattr(_handler, "save"): 

65 msg = "BUFR save handler not installed" 

66 raise OSError(msg) 

67 _handler.save(im, fp, filename) 

68 

69 

70# -------------------------------------------------------------------- 

71# Registry 

72 

73Image.register_open(BufrStubImageFile.format, BufrStubImageFile, _accept) 

74Image.register_save(BufrStubImageFile.format, _save) 

75 

76Image.register_extension(BufrStubImageFile.format, ".bufr")