diff options
Diffstat (limited to 'dns/wiredata.py')
| -rw-r--r-- | dns/wiredata.py | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/dns/wiredata.py b/dns/wiredata.py index 86d954a..1d14bd3 100644 --- a/dns/wiredata.py +++ b/dns/wiredata.py @@ -19,6 +19,18 @@ import sys import dns.exception +# Figure out what constant python passes for an unspecified slice bound. +# It's supposed to be sys.maxint, yet on 64-bit windows sys.maxint is 2^31 - 1 +# but Python uses 2^63 - 1 as the constant. Rather than making pointless +# extra comparisons, duplicating code, or weakening WireData, we just figure +# out what constant Python will use. + +class _SliceUnspecifiedBound(str): + def __getslice__(self, i, j): + return j + +_unspecified_bound = _SliceUnspecifiedBound('')[1:] + class WireData(str): # WireData is a string with stricter slicing def __getitem__(self, key): @@ -28,7 +40,7 @@ class WireData(str): raise dns.exception.FormError def __getslice__(self, i, j): try: - if j == sys.maxint: + if j == _unspecified_bound: # handle the case where the right bound is unspecified j = len(self) if i < 0 or j < 0: |