Re: [PATCH 06/15] time: Add getitimer and setitimer basic tests

[Siddhesh Poyarekar <siddhesh@gotplt.org>]

On 3/23/21 7:14 PM, Adhemerval Zanella via Libc-alpha wrote:
> Checked on i686-linux-gnu and x86_64-linux-gnu.
> ---

LGTM with a small nit fixed below.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>


>   time/Makefile     |   2 +-
>   time/tst-itimer.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 176 insertions(+), 1 deletion(-)
>   create mode 100644 time/tst-itimer.c
> 
> diff --git a/time/Makefile b/time/Makefile
> index 99b5d42666..91cb02a003 100644
> --- a/time/Makefile
> +++ b/time/Makefile
> @@ -49,7 +49,7 @@ tests	:= test_time clocktest tst-posixtz tst-strptime tst_wcsftime \
>   	   tst-tzname tst-y2039 bug-mktime4 tst-strftime2 tst-strftime3 \
>   	   tst-clock tst-clock2 tst-clock_nanosleep tst-cpuclock1 \
>   	   tst-adjtime tst-ctime tst-difftime tst-mktime4 tst-clock_settime \
> -	   tst-settimeofday
> +	   tst-settimeofday tst-itimer
>   
>   include ../Rules
>   
> diff --git a/time/tst-itimer.c b/time/tst-itimer.c
> new file mode 100644
> index 0000000000..e464d6b092
> --- /dev/null
> +++ b/time/tst-itimer.c
> @@ -0,0 +1,175 @@
> +/* Basic tests for getitimer and setitimer.
> +   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 <array_length.h>
> +#include <errno.h>
> +#include <stdlib.h>
> +#include <sys/time.h>
> +#include <support/check.h>
> +#include <support/xsignal.h>
> +#include <unistd.h>
> +#include <time.h>
> +
> +static sig_atomic_t cnt;
> +
> +static void
> +alrm_handler (int sig)
> +{
> +  if (++cnt > 3)
> +    cnt = 3;
> +}
> +
> +static void
> +intr_sleep (int sec)
> +{
> +  struct timespec ts = { .tv_sec = sec, .tv_nsec = 0 };
> +  while (nanosleep (&ts, &ts) == -1 && errno == EINTR)
> +    ;
> +}
> +
> +static int
> +do_test (void)
> +{
> +  struct itimerval it, it_old;
> +  const int timers[] = { ITIMER_REAL, ITIMER_VIRTUAL, ITIMER_PROF };
> +  for (int i = 0; i < array_length (timers); i++)
> +    {
> +      TEST_COMPARE (getitimer (timers[i], &it), 0);
> +
> +      /* No timer set, all value should be 0.  */
> +      TEST_COMPARE (it.it_interval.tv_sec, 0);
> +      TEST_COMPARE (it.it_interval.tv_usec, 0);
> +      TEST_COMPARE (it.it_value.tv_sec, 0);
> +      TEST_COMPARE (it.it_value.tv_usec, 0);
> +
> +      it.it_interval.tv_sec = 10;
> +      it.it_interval.tv_usec = 20;
> +      TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
> +
> +      TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 }, &it_old),
> +		    0);
> +      /* ITIMER_REAL returns { 0, 0 } for single-sort timers, while

s/single-sort/single-shot/

> +	 other timers returns setitimer value.  */
> +      if (timers[i] == ITIMER_REAL)
> +	{
> +	  TEST_COMPARE (it_old.it_interval.tv_sec, 0);
> +	  TEST_COMPARE (it_old.it_interval.tv_usec, 0);
> +	}
> +      else
> +	{
> +	  TEST_COMPARE (it_old.it_interval.tv_sec, 10);
> +	  TEST_COMPARE (it_old.it_interval.tv_usec, 20);
> +	}
> +
> +      /* Create a periodic timer and check if the return value is the one
> +	 previously set.  */
> +      it.it_interval.tv_sec = 10;
> +      it.it_interval.tv_usec = 20;
> +      it.it_value.tv_sec = 30;
> +      it.it_value.tv_usec = 40;
> +      TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
> +
> +      TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 }, &it_old),
> +		    0);
> +      TEST_COMPARE (it.it_interval.tv_sec, it_old.it_interval.tv_sec);
> +      TEST_COMPARE (it.it_interval.tv_usec, it_old.it_interval.tv_usec);
> +
> +      if (sizeof (time_t) == 4)
> +	continue;
> +
> +      /* Same as before, but with a 64 bit time_t value.  */
> +      it.it_interval.tv_sec = (time_t) 0x1ffffffffull;
> +      it.it_interval.tv_usec = 20;
> +      it.it_value.tv_sec = 0;
> +      it.it_value.tv_usec = 0;
> +
> +      /* Linux does not provide 64 bit time_t support for getitimer and
> +	 setitimer on architectures with 32 bit time_t support.  */
> +      if (sizeof (__time_t) == 8)
> +	{
> +	  TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
> +	  TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 },
> +				   &it_old),
> +			0);
> +	  /* ITIMER_REAL returns { 0, 0 } for single-sort timers, while other
> +	     timers returns setitimer value.  */
> +	  if (timers[i] == ITIMER_REAL)
> +	    {
> +	      TEST_COMPARE (it_old.it_interval.tv_sec, 0ull);
> +	      TEST_COMPARE (it_old.it_interval.tv_usec, 0);
> +	    }
> +	  else
> +	    {
> +	      TEST_COMPARE (it_old.it_interval.tv_sec, 0x1ffffffffull);
> +	      TEST_COMPARE (it_old.it_interval.tv_usec, 20);
> +	    }
> +	}
> +      else
> +	{
> +	  TEST_COMPARE (setitimer (timers[i], &it, NULL), -1);
> +	  TEST_COMPARE (errno, EOVERFLOW);
> +	}
> +
> +      /* Create a periodic timer and check if the return value is the one
> +	 previously set.  */
> +      it.it_interval.tv_sec = (time_t) 0x1ffffffffull;
> +      it.it_interval.tv_usec = 20;
> +      it.it_value.tv_sec = 30;
> +      it.it_value.tv_usec = 40;
> +      if (sizeof (__time_t) == 8)
> +	{
> +	  TEST_COMPARE (setitimer (timers[i], &it, NULL), 0);
> +
> +	  TEST_COMPARE (setitimer (timers[i], &(struct itimerval) { 0 },
> +				   &it_old),
> +			0);
> +	  TEST_COMPARE (it.it_interval.tv_sec, it_old.it_interval.tv_sec);
> +	  TEST_COMPARE (it.it_interval.tv_usec, it_old.it_interval.tv_usec);
> +	}
> +      else
> +	{
> +	  TEST_COMPARE (setitimer (timers[i], &it, NULL), -1);
> +	  TEST_COMPARE (errno, EOVERFLOW);
> +	}
> +  }
> +
> +  {
> +    struct sigaction sa = { .sa_handler = alrm_handler, .sa_flags = 0 };
> +    sigemptyset (&sa.sa_mask);
> +    xsigaction (SIGALRM, &sa, NULL);
> +  }
> +
> +  /* Setup a timer to 0.1s and sleep for 1s and check to 3 signal handler
> +     execution.  */
> +  it.it_interval.tv_sec = 0;
> +  it.it_interval.tv_usec = 100000;
> +  it.it_value.tv_sec = 0;
> +  it.it_value.tv_usec = 100000;
> +
> +  /* Check ITIMER_VIRTUAL and ITIMER_PROF would require to generate load
> +     and be subject to system load.  */
> +  cnt = 0;
> +  TEST_COMPARE (setitimer (ITIMER_REAL, &it, NULL), 0);
> +  intr_sleep (1);
> +  TEST_COMPARE (cnt, 3);
> +  TEST_COMPARE (setitimer (ITIMER_REAL, &(struct itimerval) { 0 }, NULL), 0);
> +
> +  return 0;
> +}
> +
> +#include <support/test-driver.c>
>