NS_TO_TV helper was implemented in 591fa59 ("MINOR: time: add conversions
to/from nanosecond timestamps")
Due to NS_TO_TV being implemented as a macro and not a function, we must
take extra care when manipulating user input.
In current implementation, 't' argument is not isolated within the macro.
Because of this, NS_TO_TV(1 + 1) will expand to:
((const struct timeval){ .tv_sec = 1 + 1 / 1000000000ULL, .tv_usec = (1 + 1 % 1000000000ULL) / 1000U })
Instead of:
((const struct timeval){ .tv_sec = 2 / 1000000000ULL, .tv_usec = (2 % 1000000000ULL) / 1000U })
As such, NS_TO_TV usage in hlua_now() is currently incorrect and this
results in unexpected values being passed to lua.
In this patch, we're adding an extra parenthesis around 't' in NS_TO_TV()
macro to make it safe against such usages. (that is: ensure proper
argument expansion as if NS_TO_TV was implemented as a function)
This is a 2.8 specific bug, no backport needed.
e910909556