diff options
| -rw-r--r-- | Modules/binascii.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/Modules/binascii.c b/Modules/binascii.c index 6cba688..66644e1 100644 --- a/Modules/binascii.c +++ b/Modules/binascii.c @@ -864,6 +864,7 @@ binascii_crc32(PyObject *self, PyObject *args) unsigned char *bin_data; unsigned long crc = 0UL; /* initial value of CRC */ int len; + long result; if ( !PyArg_ParseTuple(args, "s#|l:crc32", &bin_data, &len, &crc) ) return NULL; @@ -872,7 +873,16 @@ binascii_crc32(PyObject *self, PyObject *args) while(len--) crc = crc_32_tab[(crc ^ *bin_data++) & 0xffUL] ^ (crc >> 8); /* Note: (crc >> 8) MUST zero fill on left */ - return Py_BuildValue("l", crc ^ 0xFFFFFFFFUL); + + result = (long)(crc ^ 0xFFFFFFFFUL); + /* If long is > 32 bits, extend the sign bit. This is one way to + * ensure the result is the same across platforms. The other way + * would be to return an unbounded long, but the evidence suggests + * that lots of code outside this treats the result as if it were + * a signed 4-byte integer. + */ + result |= -(result & (1L << 31)); + return PyInt_FromLong(result); } |