Coverage for /pythoncovmergedfiles/medio/medio/src/py/py/_error.py: 31%

1""" 

2create errno-specific classes for IO or os calls. 

3 

4""" 

5from types import ModuleType 

6import sys, os, errno 

7 

8class Error(EnvironmentError): 

9 def __repr__(self): 

10 return "%s.%s %r: %s " %(self.__class__.__module__, 

11 self.__class__.__name__, 

12 self.__class__.__doc__, 

13 " ".join(map(str, self.args)), 

14 #repr(self.args) 

15 ) 

16 

17 def __str__(self): 

18 s = "[%s]: %s" %(self.__class__.__doc__, 

19 " ".join(map(str, self.args)), 

20 ) 

21 return s 

22 

23_winerrnomap = { 

24 2: errno.ENOENT, 

25 3: errno.ENOENT, 

26 17: errno.EEXIST, 

27 18: errno.EXDEV, 

28 13: errno.EBUSY, # empty cd drive, but ENOMEDIUM seems unavailiable 

29 22: errno.ENOTDIR, 

30 20: errno.ENOTDIR, 

31 267: errno.ENOTDIR, 

32 5: errno.EACCES, # anything better? 

33} 

34 

35class ErrorMaker(ModuleType): 

36 """ lazily provides Exception classes for each possible POSIX errno 

37 (as defined per the 'errno' module). All such instances 

38 subclass EnvironmentError. 

39 """ 

40 Error = Error 

41 _errno2class = {} 

42 

43 def __getattr__(self, name): 

44 if name[0] == "_": 

45 raise AttributeError(name) 

46 eno = getattr(errno, name) 

47 cls = self._geterrnoclass(eno) 

48 setattr(self, name, cls) 

49 return cls 

50 

51 def _geterrnoclass(self, eno): 

52 try: 

53 return self._errno2class[eno] 

54 except KeyError: 

55 clsname = errno.errorcode.get(eno, "UnknownErrno%d" %(eno,)) 

56 errorcls = type(Error)(clsname, (Error,), 

57 {'__module__':'py.error', 

58 '__doc__': os.strerror(eno)}) 

59 self._errno2class[eno] = errorcls 

60 return errorcls 

61 

62 def checked_call(self, func, *args, **kwargs): 

63 """ call a function and raise an errno-exception if applicable. """ 

64 __tracebackhide__ = True 

65 try: 

66 return func(*args, **kwargs) 

67 except self.Error: 

68 raise 

69 except (OSError, EnvironmentError): 

70 cls, value, tb = sys.exc_info() 

71 if not hasattr(value, 'errno'): 

72 raise 

73 __tracebackhide__ = False 

74 errno = value.errno 

75 try: 

76 if not isinstance(value, WindowsError): 

77 raise NameError 

78 except NameError: 

79 # we are not on Windows, or we got a proper OSError 

80 cls = self._geterrnoclass(errno) 

81 else: 

82 try: 

83 cls = self._geterrnoclass(_winerrnomap[errno]) 

84 except KeyError: 

85 raise value 

86 raise cls("%s%r" % (func.__name__, args)) 

87 __tracebackhide__ = True 

88 

89 

90error = ErrorMaker('py.error') 

91sys.modules[error.__name__] = error