merge 2.6 with hash randomization fix

This commit is contained in:
Benjamin Peterson 2012-02-20 21:44:56 -05:00
commit aee9dfba4a
26 changed files with 2503 additions and 140 deletions

View file

@ -6541,11 +6541,21 @@ unicode_hash(PyUnicodeObject *self)
if (self->hash != -1)
return self->hash;
len = PyUnicode_GET_SIZE(self);
/*
We make the hash of the empty string be 0, rather than using
(prefix ^ suffix), since this slightly obfuscates the hash secret
*/
if (len == 0) {
self->hash = 0;
return 0;
}
p = PyUnicode_AS_UNICODE(self);
x = *p << 7;
x = _Py_HashSecret.prefix;
x ^= *p << 7;
while (--len >= 0)
x = (1000003*x) ^ *p++;
x ^= PyUnicode_GET_SIZE(self);
x ^= _Py_HashSecret.suffix;
if (x == -1)
x = -2;
self->hash = x;