winliteutils.py

   1 #Copyright (c) 2008 Vincent Povirk
   2 #
   3 #Permission is hereby granted, free of charge, to any person
   4 #obtaining a copy of this software and associated documentation
   5 #files (the "Software"), to deal in the Software without
   6 #restriction, including without limitation the rights to use,
   7 #copy, modify, merge, publish, distribute, sublicense, and/or sell
   8 #copies of the Software, and to permit persons to whom the
   9 #Software is furnished to do so, subject to the following
  10 #conditions:
  11 #
  12 #The above copyright notice and this permission notice shall be
  13 #included in all copies or substantial portions of the Software.
  14 #
  15 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16 #EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  17 #OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18 #NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19 #HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20 #WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21 #FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22 #OTHER DEALINGS IN THE SOFTWARE.
  23
  24 from ctypes import GetLastError, WinError
  25
  26 class collapsed_attr(object):
  27     __fields__ = ['attr', 'subattr']
  28
  29     def __init__(self, attr, subattr):
  30         self.attr = attr
  31         self.subattr = subattr
  32
  33     def __get__(self, instance, owner):
  34         return getattr(getattr(instance or owner, self.attr), self.subattr)
  35
  36     def __set__(self, instance, value):
  37         setattr(getattr(instance, self.attr), self.subattr, value)
  38
  39     def __delete__(self, instance):
  40         delattr(getattr(instance, self.attr), self.subattr)
  41
  42 class WinLiteException(Exception):
  43     pass
  44
  45 def CheckError():
  46     "CheckError() - raise a WindowsError if GetLastError() returns a non-zero value"
  47     err = GetLastError()
  48     if err:
  49         raise WinError()
  50
  51 def NONZERO(i):
  52     if i == 0 and GetLastError() != 0:
  53         raise WinError()
  54     return i
  55
  56 def ZERO(i):
  57     if i != 0 and GetLastError() != 0:
  58         exc = WinError()
  59         exc.result = i
  60         raise exc
  61     return i
  62
  63 class ERRFLAGS(object):
  64     __fields__ = ['flags']
  65
  66     def __init__(self, module_dict, prefix):
  67         self.flags = {}
  68         for name in module_dict:
  69             if name.startswith(prefix):
  70                 self.flags[name] = module_dict[name]
  71
  72     def __call__(self, i):
  73         if i != 0:
  74             flags = []
  75             for name in self.flags:
  76                 if self.flags[name] & i:
  77                     flags.append(name)
  78             e = WinLiteException('|'.join(flags))
  79             e.flags = i
  80             raise e
  81         return i
  82
  83 def get_symbols(globals, module, names):
  84     for name in names:
  85         globals[name] = getattr(module, name)
  86