84 lines
2.6 KiB
Python
84 lines
2.6 KiB
Python
"""
|
|
create errno-specific classes for IO or os calls.
|
|
|
|
"""
|
|
import sys, os, errno
|
|
|
|
class Error(EnvironmentError):
|
|
def __repr__(self):
|
|
return "%s.%s %r: %s " %(self.__class__.__module__,
|
|
self.__class__.__name__,
|
|
self.__class__.__doc__,
|
|
" ".join(map(str, self.args)),
|
|
#repr(self.args)
|
|
)
|
|
|
|
def __str__(self):
|
|
s = "[%s]: %s" %(self.__class__.__doc__,
|
|
" ".join(map(str, self.args)),
|
|
)
|
|
return s
|
|
|
|
_winerrnomap = {
|
|
2: errno.ENOENT,
|
|
3: errno.ENOENT,
|
|
17: errno.EEXIST,
|
|
22: errno.ENOTDIR,
|
|
267: errno.ENOTDIR,
|
|
5: errno.EACCES, # anything better?
|
|
}
|
|
|
|
class ErrorMaker(object):
|
|
""" lazily provides Exception classes for each possible POSIX errno
|
|
(as defined per the 'errno' module). All such instances
|
|
subclass EnvironmentError.
|
|
"""
|
|
Error = Error
|
|
_errno2class = {}
|
|
|
|
def __getattr__(self, name):
|
|
eno = getattr(errno, name)
|
|
cls = self._geterrnoclass(eno)
|
|
setattr(self, name, cls)
|
|
return cls
|
|
|
|
def _geterrnoclass(self, eno):
|
|
try:
|
|
return self._errno2class[eno]
|
|
except KeyError:
|
|
clsname = errno.errorcode.get(eno, "UnknownErrno%d" %(eno,))
|
|
errorcls = type(Error)(clsname, (Error,),
|
|
{'__module__':'py.error',
|
|
'__doc__': os.strerror(eno)})
|
|
self._errno2class[eno] = errorcls
|
|
return errorcls
|
|
|
|
def checked_call(self, func, *args):
|
|
""" call a function and raise an errno-exception if applicable. """
|
|
__tracebackhide__ = True
|
|
try:
|
|
return func(*args)
|
|
except self.Error:
|
|
raise
|
|
except EnvironmentError:
|
|
cls, value, tb = sys.exc_info()
|
|
if not hasattr(value, 'errno'):
|
|
raise
|
|
__tracebackhide__ = False
|
|
errno = value.errno
|
|
try:
|
|
if not isinstance(value, WindowsError):
|
|
raise NameError
|
|
except NameError:
|
|
# we are not on Windows, or we got a proper OSError
|
|
cls = self._geterrnoclass(errno)
|
|
else:
|
|
try:
|
|
cls = self._geterrnoclass(_winerrnomap[eno])
|
|
except KeyError:
|
|
raise value
|
|
raise cls("%s%r" % (func.__name__, args))
|
|
__tracebackhide__ = True
|
|
|
|
error = ErrorMaker()
|