NetBSD 8 adds support of AF_CAN (previously it was supported only on Linux). This causes a compilation error in socketmodule.c, because AF_CAN is defined in sys/socket.h, but sys/socket.h itself doesn't contain all necessary definitions for handling AF_CAN addresses. This also exposed other errors. The braces are not balanced if AF_CAN is defined, but CAN_RAW and CAN_BCM are not. PyBytes_AS_STRING() is called for non-bytes.

The proposed patch balances #ifdef/#endif with braces, undefines AF_CAN if it is not usable (following the practice for other AF_* constants), separates support of CAN_RAW and CAN_BCM (only the former is defined on NetBSD 8), adds comments to #endif for helping with navigation, adds the const qualifier to char pointers that always point to constant data, fixes indentation.

This fixed a compilation on NetBSD 8, and I hope this will fix a compilation on other platforms that will add AF_CAN. In a separate issue I'll add a support of AF_CAN on NetBSD (in 3.7 only).

New changeset d3187158c09cf899e9849f335bdff10594209167 by Serhiy Storchaka in branch 'master':
bpo-31927: Fix bugs in socketmodule.c on NetBSD and other issues. (#4235)
https://github.com/python/cpython/commit/d3187158c09cf899e9849f335bdff10594209167

New changeset 596286f8f3c8e53ef010d6298464775dc900a515 by Serhiy Storchaka in branch '3.6':
[3.6] bpo-31927: Fix bugs in socketmodule.c on NetBSD and other issues. (GH-4235) (#4352)
https://github.com/python/cpython/commit/596286f8f3c8e53ef010d6298464775dc900a515

New changeset 1bce4efdb4624561adce62e544dbe20ec2627ae2 by Serhiy Storchaka in branch '2.7':
[2.7] bpo-31927: Fix reading arbitrary data when parse a AF_BLUETOOTH address (GH-4235) (GH-4352) (#4355)
https://github.com/python/cpython/commit/1bce4efdb4624561adce62e544dbe20ec2627ae2