glibc/time/tst-timespec_getres.c
Joseph Myers e5ac7bd679 Add C2X timespec_getres
ISO C2X adds a timespec_getres function alongside the C11
timespec_get, with functionality similar to that of POSIX clock_getres
(including allowing a NULL pointer to be passed to the function).
Implement this function for glibc, similarly to the implementation of
timespec_get.

This includes a basic test like that of timespec_get, but no
documentation in the manual, given that TIME_UTC and timespec_get
aren't documented in the manual at all.  The handling of 64-bit time
follows that in timespec_get; people maintaining patch series for
64-bit time will need to update them accordingly (to export
__timespec_getres64, redirect calls in time.h and run the test for
_TIME_BITS=64).

Tested for x86_64 and x86, and (previous version; only testcase
differs) with build-many-glibcs.py.
2021-05-17 20:55:21 +00:00

52 lines
1.7 KiB
C

/* Basic tests for timespec_getres.
Copyright (C) 2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <time.h>
#include <support/check.h>
static int
do_test (void)
{
{
struct timespec ts;
TEST_COMPARE (timespec_getres (&ts, 0), 0);
TEST_COMPARE (timespec_getres (NULL, 0), 0);
}
{
struct timespec ts;
TEST_COMPARE (timespec_getres (&ts, TIME_UTC), TIME_UTC);
/* Expect all supported systems to support TIME_UTC with
resolution better than one second. */
TEST_VERIFY (ts.tv_sec == 0);
TEST_VERIFY (ts.tv_nsec > 0);
TEST_VERIFY (ts.tv_nsec < 1000000000);
TEST_COMPARE (timespec_getres (NULL, TIME_UTC), TIME_UTC);
/* Expect the resolution to be the same as that reported for
CLOCK_REALTIME with clock_getres. */
struct timespec cts;
TEST_COMPARE (clock_getres (CLOCK_REALTIME, &cts), 0);
TEST_COMPARE (ts.tv_sec, cts.tv_sec);
TEST_COMPARE (ts.tv_nsec, cts.tv_nsec);
}
return 0;
}
#include <support/test-driver.c>