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Re: PATCH [3/n]: Add __snseconds_t and __SNSECONDS_T_TYPE
On 03/15/2012 01:26 PM, H.J. Lu wrote:
> struct timespec
> {
> __time_t tv_sec; /* Seconds. */
> - long int tv_nsec; /* Nanoseconds. */
> + __snseconds_t tv_nsec; /* Nanoseconds. */
> };
This patch does not look right. POSIX says that tv_nsec must
be of type 'long'; it cannot be of type 'long long'. See
<http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/time.h.html>.
Instead, I suggest redoing the patch so that there is a 4-byte
filler in the data structure on x32. There should be no need
to introduce __snseconds_t or __SNSECONDS_T_TYPE; just use
'long'. When passing the data structure to the kernel, you can
sign-extend tv_nsec into the filler. You can ignore the filler
when getting the data structure back from the kernel, since it
should always be appropriately sign-extended.