[2/5] nptl: Convert tst-cond11.c to use libsupport

Message ID ccd351f58a9cf8f6ed50ac99da741857d09e260a.1556830454.git-series.mac@mcrowe.com
State New
Headers show
Series
  • Add new helper functions+macros to libsupport and use them in some nptl tests
Related show

Commit Message

Mike Crowe May 2, 2019, 8:54 p.m.
* support/timespec.h: New file. Provide timespec helper functions
	along with macros in the style of those in check.h.

	* support/timespec.c: New file. Implement check functions declared
	in support/timespec.h.

	* support/timespec-add.c: New file from gnulib containing
	timespec_add implementation that handles overflow.

	* support/timespec-sub.c: New file from gnulib containing
	timespec_sub implementation that handles overflow.

	* support/README: Mention timespec.h.

	* nptl/tst-cond11.c: Use libsupport.
---
 ChangeLog              |  18 ++++-
 nptl/tst-cond11.c      | 169 ++++++++----------------------------------
 support/Makefile       |   3 +-
 support/README         |   5 +-
 support/timespec-add.c |  71 ++++++++++++++++++-
 support/timespec-sub.c |  71 ++++++++++++++++++-
 support/timespec.c     |  58 ++++++++++++++-
 support/timespec.h     |  79 ++++++++++++++++++++-
 8 files changed, 341 insertions(+), 133 deletions(-)
 create mode 100644 support/timespec-add.c
 create mode 100644 support/timespec-sub.c
 create mode 100644 support/timespec.c
 create mode 100644 support/timespec.h

-- 
git-series 0.9.1

Comments

Adhemerval Zanella May 9, 2019, 4:39 p.m. | #1
On 02/05/2019 17:54, Mike Crowe wrote:
> * support/timespec.h: New file. Provide timespec helper functions

> 	along with macros in the style of those in check.h.

> 

> 	* support/timespec.c: New file. Implement check functions declared

> 	in support/timespec.h.

> 

> 	* support/timespec-add.c: New file from gnulib containing

> 	timespec_add implementation that handles overflow.

> 

> 	* support/timespec-sub.c: New file from gnulib containing

> 	timespec_sub implementation that handles overflow.

> 

> 	* support/README: Mention timespec.h.

> 

> 	* nptl/tst-cond11.c: Use libsupport.


Still LGTM.  I will push it for you.

> ---

>  ChangeLog              |  18 ++++-

>  nptl/tst-cond11.c      | 169 ++++++++----------------------------------

>  support/Makefile       |   3 +-

>  support/README         |   5 +-

>  support/timespec-add.c |  71 ++++++++++++++++++-

>  support/timespec-sub.c |  71 ++++++++++++++++++-

>  support/timespec.c     |  58 ++++++++++++++-

>  support/timespec.h     |  79 ++++++++++++++++++++-

>  8 files changed, 341 insertions(+), 133 deletions(-)

>  create mode 100644 support/timespec-add.c

>  create mode 100644 support/timespec-sub.c

>  create mode 100644 support/timespec.c

>  create mode 100644 support/timespec.h

> 

> diff --git a/ChangeLog b/ChangeLog

> index 6008265..cd0ef83 100644

> --- a/ChangeLog

> +++ b/ChangeLog

> @@ -1,5 +1,23 @@

>  2019-05-02  Mike Crowe  <mac@mcrowe.com>

>  

> +	* support/timespec.h: New file. Provide timespec helper functions

> +	along with macros in the style of those in check.h.

> +

> +	* support/timespec.c: New file. Implement check functions declared

> +	in support/timespec.h.

> +

> +	* support/timespec-add.c: New file from gnulib containing

> +	timespec_add implementation that handles overflow.

> +

> +	* support/timespec-sub.c: New file from gnulib containing

> +	timespec_sub implementation that handles overflow.

> +

> +	* support/README: Mention timespec.h.

> +

> +	* nptl/tst-cond11.c: Use libsupport.

> +

> +2019-05-02  Mike Crowe  <mac@mcrowe.com>

> +

>  	* support/xclock_gettime.c (xclock_gettime): New file. Provide

>  	clock_gettime wrapper for use in tests that fails the test rather

>  	than returning failure.

> diff --git a/nptl/tst-cond11.c b/nptl/tst-cond11.c

> index 97a8bd0..3bc4ff4 100644

> --- a/nptl/tst-cond11.c

> +++ b/nptl/tst-cond11.c

> @@ -21,6 +21,10 @@

>  #include <stdio.h>

>  #include <time.h>

>  #include <unistd.h>

> +#include <support/check.h>

> +#include <support/timespec.h>

> +#include <support/xthread.h>

> +#include <support/xtime.h>

>  

>  

>  #if defined _POSIX_CLOCK_SELECTION && _POSIX_CLOCK_SELECTION >= 0

> @@ -34,132 +38,36 @@ run_test (clockid_t cl)

>  

>    printf ("clock = %d\n", (int) cl);

>  

> -  if (pthread_condattr_init (&condattr) != 0)

> -    {

> -      puts ("condattr_init failed");

> -      return 1;

> -    }

> -

> -  if (pthread_condattr_setclock (&condattr, cl) != 0)

> -    {

> -      puts ("condattr_setclock failed");

> -      return 1;

> -    }

> +  TEST_COMPARE (pthread_condattr_init (&condattr), 0);

> +  TEST_COMPARE (pthread_condattr_setclock (&condattr, cl), 0);

>  

>    clockid_t cl2;

> -  if (pthread_condattr_getclock (&condattr, &cl2) != 0)

> -    {

> -      puts ("condattr_getclock failed");

> -      return 1;

> -    }

> -  if (cl != cl2)

> -    {

> -      printf ("condattr_getclock returned wrong value: %d, expected %d\n",

> -	      (int) cl2, (int) cl);

> -      return 1;

> -    }

> -

> -  if (pthread_cond_init (&cond, &condattr) != 0)

> -    {

> -      puts ("cond_init failed");

> -      return 1;

> -    }

> -

> -  if (pthread_condattr_destroy (&condattr) != 0)

> -    {

> -      puts ("condattr_destroy failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutexattr_init (&mutattr) != 0)

> -    {

> -      puts ("mutexattr_init failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutexattr_settype (&mutattr, PTHREAD_MUTEX_ERRORCHECK) != 0)

> -    {

> -      puts ("mutexattr_settype failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutex_init (&mut, &mutattr) != 0)

> -    {

> -      puts ("mutex_init failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutexattr_destroy (&mutattr) != 0)

> -    {

> -      puts ("mutexattr_destroy failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutex_lock (&mut) != 0)

> -    {

> -      puts ("mutex_lock failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutex_lock (&mut) != EDEADLK)

> -    {

> -      puts ("2nd mutex_lock did not return EDEADLK");

> -      return 1;

> -    }

> -

> -  struct timespec ts;

> -  if (clock_gettime (cl, &ts) != 0)

> -    {

> -      puts ("clock_gettime failed");

> -      return 1;

> -    }

> +  TEST_COMPARE (pthread_condattr_getclock (&condattr, &cl2), 0);

> +  TEST_COMPARE (cl, cl2);

> +

> +  TEST_COMPARE (pthread_cond_init (&cond, &condattr), 0);

> +  TEST_COMPARE (pthread_condattr_destroy (&condattr), 0);

> +

> +  xpthread_mutexattr_init (&mutattr);

> +  xpthread_mutexattr_settype (&mutattr, PTHREAD_MUTEX_ERRORCHECK);

> +  xpthread_mutex_init (&mut, &mutattr);

> +  xpthread_mutexattr_destroy (&mutattr);

> +

> +  xpthread_mutex_lock (&mut);

> +  TEST_COMPARE (pthread_mutex_lock (&mut), EDEADLK);

> +

> +  struct timespec ts_timeout;

> +  xclock_gettime (cl, &ts_timeout);

>  

>    /* Wait one second.  */

> -  ++ts.tv_sec;

> -

> -  int e = pthread_cond_timedwait (&cond, &mut, &ts);

> -  if (e == 0)

> -    {

> -      puts ("cond_timedwait succeeded");

> -      return 1;

> -    }

> -  else if (e != ETIMEDOUT)

> -    {

> -      puts ("cond_timedwait did not return ETIMEDOUT");

> -      return 1;

> -    }

> -

> -  struct timespec ts2;

> -  if (clock_gettime (cl, &ts2) != 0)

> -    {

> -      puts ("second clock_gettime failed");

> -      return 1;

> -    }

> -

> -  if (ts2.tv_sec < ts.tv_sec

> -      || (ts2.tv_sec == ts.tv_sec && ts2.tv_nsec < ts.tv_nsec))

> -    {

> -      puts ("timeout too short");

> -      return 1;

> -    }

> -

> -  if (pthread_mutex_unlock (&mut) != 0)

> -    {

> -      puts ("mutex_unlock failed");

> -      return 1;

> -    }

> -

> -  if (pthread_mutex_destroy (&mut) != 0)

> -    {

> -      puts ("mutex_destroy failed");

> -      return 1;

> -    }

> -

> -  if (pthread_cond_destroy (&cond) != 0)

> -    {

> -      puts ("cond_destroy failed");

> -      return 1;

> -    }

> +  ++ts_timeout.tv_sec;

> +

> +  TEST_COMPARE (pthread_cond_timedwait (&cond, &mut, &ts_timeout), ETIMEDOUT);

> +  TEST_TIMESPEC_BEFORE_NOW (ts_timeout, cl);

> +

> +  xpthread_mutex_unlock (&mut);

> +  xpthread_mutex_destroy (&mut);

> +  TEST_COMPARE (pthread_cond_destroy (&cond), 0);

>  

>    return 0;

>  }

> @@ -171,12 +79,11 @@ do_test (void)

>  {

>  #if !defined _POSIX_CLOCK_SELECTION || _POSIX_CLOCK_SELECTION == -1

>  

> -  puts ("_POSIX_CLOCK_SELECTION not supported, test skipped");

> -  return 0;

> +  FAIL_UNSUPPORTED ("_POSIX_CLOCK_SELECTION not supported, test skipped");

>  

>  #else

>  

> -  int res = run_test (CLOCK_REALTIME);

> +  run_test (CLOCK_REALTIME);

>  

>  # if defined _POSIX_MONOTONIC_CLOCK && _POSIX_MONOTONIC_CLOCK >= 0

>  #  if _POSIX_MONOTONIC_CLOCK == 0

> @@ -184,20 +91,16 @@ do_test (void)

>    if (e < 0)

>      puts ("CLOCK_MONOTONIC not supported");

>    else if (e == 0)

> -    {

> -      puts ("sysconf (_SC_MONOTONIC_CLOCK) must not return 0");

> -      res = 1;

> -    }

> +      FAIL_RET ("sysconf (_SC_MONOTONIC_CLOCK) must not return 0");

>    else

>  #  endif

> -    res |= run_test (CLOCK_MONOTONIC);

> +    run_test (CLOCK_MONOTONIC);

>  # else

>    puts ("_POSIX_MONOTONIC_CLOCK not defined");

>  # endif

>  

> -  return res;

> +  return 0;

>  #endif

>  }

>  

> -#define TEST_FUNCTION do_test ()

> -#include "../test-skeleton.c"

> +#include <support/test-driver.c>

> diff --git a/support/Makefile b/support/Makefile

> index 05865fe..64044f6 100644

> --- a/support/Makefile

> +++ b/support/Makefile

> @@ -71,6 +71,9 @@ libsupport-routines = \

>    support_test_main \

>    support_test_verify_impl \

>    temp_file \

> +  timespec \

> +  timespec-add \

> +  timespec-sub \

>    write_message \

>    xaccept \

>    xaccept4 \

> diff --git a/support/README b/support/README

> index d82f472..ae2c41c 100644

> --- a/support/README

> +++ b/support/README

> @@ -28,3 +28,8 @@ header files provide related declarations:

>  * check.h

>  * temp_file.h

>  * test-driver.h

> +

> +For tests that make use of struct timespec, the following header files

> +contain additional macros and helper functions:

> +

> +* timespec.h

> diff --git a/support/timespec-add.c b/support/timespec-add.c

> new file mode 100644

> index 0000000..be7a590

> --- /dev/null

> +++ b/support/timespec-add.c

> @@ -0,0 +1,71 @@

> +/* Add two struct timespec values.

> +   Copyright (C) 2011-2019 Free Software Foundation, Inc.

> +   This file is part of the GNU C Library and is also part of gnulib.

> +   Patches to this file should be submitted to both projects.

> +

> +   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

> +   <http://www.gnu.org/licenses/>.  */

> +

> +/* Return the sum of two timespec values A and B.  On overflow, return

> +   an extremal value.  This assumes 0 <= tv_nsec < TIMESPEC_HZ.  */

> +

> +#include <config.h>

> +#include "timespec.h"

> +

> +#include "intprops.h"

> +

> +struct timespec

> +timespec_add (struct timespec a, struct timespec b)

> +{

> +  time_t rs = a.tv_sec;

> +  time_t bs = b.tv_sec;

> +  int ns = a.tv_nsec + b.tv_nsec;

> +  int nsd = ns - TIMESPEC_HZ;

> +  int rns = ns;

> +  time_t tmin = TYPE_MINIMUM (time_t);

> +  time_t tmax = TYPE_MAXIMUM (time_t);

> +

> +  if (0 <= nsd)

> +    {

> +      rns = nsd;

> +      if (bs < tmax)

> +        bs++;

> +      else if (rs < 0)

> +        rs++;

> +      else

> +        goto high_overflow;

> +    }

> +

> +  /* INT_ADD_WRAPV is not appropriate since time_t might be unsigned.

> +     In theory time_t might be narrower than int, so plain

> +     INT_ADD_OVERFLOW does not suffice.  */

> +  if (! INT_ADD_OVERFLOW (rs, bs) && tmin <= rs + bs && rs + bs <= tmax)

> +    rs += bs;

> +  else

> +    {

> +      if (rs < 0)

> +        {

> +          rs = tmin;

> +          rns = 0;

> +        }

> +      else

> +        {

> +        high_overflow:

> +          rs = tmax;

> +          rns = TIMESPEC_HZ - 1;

> +        }

> +    }

> +

> +  return make_timespec (rs, rns);

> +}

> diff --git a/support/timespec-sub.c b/support/timespec-sub.c

> new file mode 100644

> index 0000000..bf95c7f

> --- /dev/null

> +++ b/support/timespec-sub.c

> @@ -0,0 +1,71 @@

> +/* Subtract two struct timespec values.

> +   Copyright (C) 2011-2019 Free Software Foundation, Inc.

> +   This file is part of the GNU C Library and is also part of gnulib.

> +   Patches to this file should be submitted to both projects.

> +

> +   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

> +   <http://www.gnu.org/licenses/>.  */

> +

> +/* Return the difference between two timespec values A and B.  On

> +   overflow, return an extremal value.  This assumes 0 <= tv_nsec <

> +   TIMESPEC_HZ.  */

> +

> +#include <config.h>

> +#include "timespec.h"

> +

> +#include "intprops.h"

> +

> +struct timespec

> +timespec_sub (struct timespec a, struct timespec b)

> +{

> +  time_t rs = a.tv_sec;

> +  time_t bs = b.tv_sec;

> +  int ns = a.tv_nsec - b.tv_nsec;

> +  int rns = ns;

> +  time_t tmin = TYPE_MINIMUM (time_t);

> +  time_t tmax = TYPE_MAXIMUM (time_t);

> +

> +  if (ns < 0)

> +    {

> +      rns = ns + TIMESPEC_HZ;

> +      if (bs < tmax)

> +        bs++;

> +      else if (- TYPE_SIGNED (time_t) < rs)

> +        rs--;

> +      else

> +        goto low_overflow;

> +    }

> +

> +  /* INT_SUBTRACT_WRAPV is not appropriate since time_t might be unsigned.

> +     In theory time_t might be narrower than int, so plain

> +     INT_SUBTRACT_OVERFLOW does not suffice.  */

> +  if (! INT_SUBTRACT_OVERFLOW (rs, bs) && tmin <= rs - bs && rs - bs <= tmax)

> +    rs -= bs;

> +  else

> +    {

> +      if (rs < 0)

> +        {

> +        low_overflow:

> +          rs = tmin;

> +          rns = 0;

> +        }

> +      else

> +        {

> +          rs = tmax;

> +          rns = TIMESPEC_HZ - 1;

> +        }

> +    }

> +

> +  return make_timespec (rs, rns);

> +}

> diff --git a/support/timespec.c b/support/timespec.c

> new file mode 100644

> index 0000000..f1b88c1

> --- /dev/null

> +++ b/support/timespec.c

> @@ -0,0 +1,58 @@

> +/* Support code for timespec checks.

> +   Copyright (C) 2019 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

> +   <http://www.gnu.org/licenses/>.  */

> +

> +#include <support/timespec.h>

> +#include <stdio.h>

> +

> +void

> +test_timespec_before_impl (const char *file, int line,

> +			   const struct timespec left,

> +			   const struct timespec right)

> +{

> +  if (left.tv_sec > right.tv_sec

> +      || (left.tv_sec == right.tv_sec

> +	  && left.tv_nsec > right.tv_nsec)) {

> +    support_record_failure ();

> +    const struct timespec diff = timespec_sub (left, right);

> +    printf ("%s:%d: %ld.%09lds not before %ld.%09lds "

> +	    "(difference %ld.%09lds)n",

> +	    file, line,

> +	    left.tv_sec, left.tv_nsec,

> +	    right.tv_sec, right.tv_nsec,

> +	    diff.tv_sec, diff.tv_nsec);

> +  }

> +}

> +

> +void

> +test_timespec_equal_or_after_impl (const char *file, int line,

> +				   const struct timespec left,

> +				   const struct timespec right)

> +{

> +  if (left.tv_sec < right.tv_sec

> +      || (left.tv_sec == right.tv_sec

> +	  && left.tv_nsec < right.tv_nsec)) {

> +    support_record_failure ();

> +    const struct timespec diff = timespec_sub (right, left);

> +    printf ("%s:%d: %ld.%09lds not after %ld.%09lds "

> +	    "(difference %ld.%09lds)n",

> +	    file, line,

> +	    left.tv_sec, left.tv_nsec,

> +	    right.tv_sec, right.tv_nsec,

> +	    diff.tv_sec, diff.tv_nsec);

> +  }

> +}

> diff --git a/support/timespec.h b/support/timespec.h

> new file mode 100644

> index 0000000..4a8b341

> --- /dev/null

> +++ b/support/timespec.h

> @@ -0,0 +1,79 @@

> +/* Useful functions for tests that use struct timespec.

> +   Copyright (C) 2019 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

> +   <http://www.gnu.org/licenses/>.  */

> +

> +#ifndef SUPPORT_TIMESPEC_H

> +#define SUPPORT_TIMESPEC_H

> +

> +#include <stdio.h>

> +#include <time.h>

> +#include <support/check.h>

> +#include <support/xtime.h>

> +

> +struct timespec timespec_add (struct timespec, struct timespec)

> +  __attribute__((const));

> +struct timespec timespec_sub (struct timespec, struct timespec)

> +  __attribute__((const));

> +

> +static inline struct timespec

> +make_timespec (time_t s, long int ns)

> +{

> +  struct timespec r;

> +  r.tv_sec = s;

> +  r.tv_nsec = ns;

> +  return r;

> +}

> +

> +enum { TIMESPEC_HZ = 1000000000 };

> +

> +void test_timespec_before_impl (const char *file, int line,

> +                                const struct timespec left,

> +                                const struct timespec right);

> +

> +void test_timespec_equal_or_after_impl (const char *file, int line,

> +                                        const struct timespec left,

> +                                        const struct timespec right);

> +

> +/* Check that the timespec on the left represents a time before the

> +   time on the right. */

> +#define TEST_TIMESPEC_BEFORE(left, right)                               \

> +  test_timespec_before_impl (__FILE__, __LINE__, (left), (right))

> +

> +#define TEST_TIMESPEC_BEFORE_NOW(left, clockid)                 \

> +  ({                                                            \

> +    struct timespec now;                                        \

> +    const int saved_errno = errno;                              \

> +    xclock_gettime ((clockid), &now);                           \

> +    TEST_TIMESPEC_BEFORE ((left), now);                         \

> +    errno = saved_errno;                                        \

> +  })

> +

> +/* Check that the timespec on the left represents a after before the

> +   time on the right. */

> +#define TEST_TIMESPEC_EQUAL_OR_AFTER(left, right)                       \

> +  test_timespec_equal_or_after_impl (__FILE__, __LINE__, left, right)

> +

> +#define TEST_TIMESPEC_NOW_OR_AFTER(clockid, right)              \

> +  ({                                                            \

> +    struct timespec now;                                        \

> +    const int saved_errno = errno;                              \

> +    xclock_gettime ((clockid), &now);                           \

> +    TEST_TIMESPEC_EQUAL_OR_AFTER (now, (right));                \

> +    errno = saved_errno;                                        \

> +  })

> +

> +#endif /* SUPPORT_TIMESPEC_H */

>
Florian Weimer May 9, 2019, 5:08 p.m. | #2
* Adhemerval Zanella:

>>  support/Makefile       |   3 +-

>>  support/README         |   5 +-

>>  support/timespec-add.c |  71 ++++++++++++++++++-

>>  support/timespec-sub.c |  71 ++++++++++++++++++-

>>  support/timespec.c     |  58 ++++++++++++++-

>>  support/timespec.h     |  79 ++++++++++++++++++++-


Could you push these changes as a separate commit?  Thanks.

Florian
Adhemerval Zanella May 9, 2019, 5:16 p.m. | #3
On 09/05/2019 14:08, Florian Weimer wrote:
> * Adhemerval Zanella:

> 

>>>  support/Makefile       |   3 +-

>>>  support/README         |   5 +-

>>>  support/timespec-add.c |  71 ++++++++++++++++++-

>>>  support/timespec-sub.c |  71 ++++++++++++++++++-

>>>  support/timespec.c     |  58 ++++++++++++++-

>>>  support/timespec.h     |  79 ++++++++++++++++++++-

> 

> Could you push these changes as a separate commit?  Thanks.

> 

> Florian

> 

Ok, I will split the patch.
Joseph Myers May 9, 2019, 11:03 p.m. | #4
On Thu, 9 May 2019, Adhemerval Zanella wrote:

> On 09/05/2019 14:08, Florian Weimer wrote:

> > * Adhemerval Zanella:

> > 

> >>>  support/Makefile       |   3 +-

> >>>  support/README         |   5 +-

> >>>  support/timespec-add.c |  71 ++++++++++++++++++-

> >>>  support/timespec-sub.c |  71 ++++++++++++++++++-

> >>>  support/timespec.c     |  58 ++++++++++++++-

> >>>  support/timespec.h     |  79 ++++++++++++++++++++-

> > 

> > Could you push these changes as a separate commit?  Thanks.

> > 

> > Florian

> > 

> Ok, I will split the patch.


These changes have broken the build for x32, with errors such as:

timespec.c: In function 'test_timespec_before_impl':
timespec.c:32:23: error: format '%ld' expects argument of type 'long int', but argument 4 has type '__time_t' {aka 'const long long int'} [-Werror=format=]

-- 
Joseph S. Myers
joseph@codesourcery.com
Adhemerval Zanella May 10, 2019, 9:42 a.m. | #5
> Il giorno 9 mag 2019, alle ore 20:03, Joseph Myers <joseph@codesourcery.com> ha scritto:

> 

>> On Thu, 9 May 2019, Adhemerval Zanella wrote:

>> 

>>> On 09/05/2019 14:08, Florian Weimer wrote:

>>> * Adhemerval Zanella:

>>> 

>>>>> support/Makefile       |   3 +-

>>>>> support/README         |   5 +-

>>>>> support/timespec-add.c |  71 ++++++++++++++++++-

>>>>> support/timespec-sub.c |  71 ++++++++++++++++++-

>>>>> support/timespec.c     |  58 ++++++++++++++-

>>>>> support/timespec.h     |  79 ++++++++++++++++++++-

>>> 

>>> Could you push these changes as a separate commit?  Thanks.

>>> 

>>> Florian

>>> 

>> Ok, I will split the patch.

> 

> These changes have broken the build for x32, with errors such as:

> 

> timespec.c: In function 'test_timespec_before_impl':

> timespec.c:32:23: error: format '%ld' expects argument of type 'long int', but argument 4 has type '__time_t' {aka 'const long long int'} [-Werror=format=]


I will check this out.
Adhemerval Zanella May 10, 2019, 12:20 p.m. | #6
On 10/05/2019 06:42, Adhemerval Zanella wrote:
> 

> 

>> Il giorno 9 mag 2019, alle ore 20:03, Joseph Myers <joseph@codesourcery.com> ha scritto:

>>

>>> On Thu, 9 May 2019, Adhemerval Zanella wrote:

>>>

>>>> On 09/05/2019 14:08, Florian Weimer wrote:

>>>> * Adhemerval Zanella:

>>>>

>>>>>> support/Makefile       |   3 +-

>>>>>> support/README         |   5 +-

>>>>>> support/timespec-add.c |  71 ++++++++++++++++++-

>>>>>> support/timespec-sub.c |  71 ++++++++++++++++++-

>>>>>> support/timespec.c     |  58 ++++++++++++++-

>>>>>> support/timespec.h     |  79 ++++++++++++++++++++-

>>>>

>>>> Could you push these changes as a separate commit?  Thanks.

>>>>

>>>> Florian

>>>>

>>> Ok, I will split the patch.

>>

>> These changes have broken the build for x32, with errors such as:

>>

>> timespec.c: In function 'test_timespec_before_impl':

>> timespec.c:32:23: error: format '%ld' expects argument of type 'long int', but argument 4 has type '__time_t' {aka 'const long long int'} [-Werror=format=]

> 

> I will check this out.

> 


I will check the following patch to fix it:

---
diff --git a/support/timespec.c b/support/timespec.c
index f1b88c1f4c..653293970a 100644
--- a/support/timespec.c
+++ b/support/timespec.c
@@ -18,6 +18,7 @@
 
 #include <support/timespec.h>
 #include <stdio.h>
+#include <stdint.h>
 
 void
 test_timespec_before_impl (const char *file, int line,
@@ -29,12 +30,12 @@ test_timespec_before_impl (const char *file, int line,
          && left.tv_nsec > right.tv_nsec)) {
     support_record_failure ();
     const struct timespec diff = timespec_sub (left, right);
-    printf ("%s:%d: %ld.%09lds not before %ld.%09lds "
-           "(difference %ld.%09lds)n",
+    printf ("%s:%d: %jd.%09jds not before %jd.%09jds "
+           "(difference %jd.%09jds)n",
            file, line,
-           left.tv_sec, left.tv_nsec,
-           right.tv_sec, right.tv_nsec,
-           diff.tv_sec, diff.tv_nsec);
+           (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
+           (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
+           (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
   }
 }
 
@@ -48,11 +49,11 @@ test_timespec_equal_or_after_impl (const char *file, int line,
          && left.tv_nsec < right.tv_nsec)) {
     support_record_failure ();
     const struct timespec diff = timespec_sub (right, left);
-    printf ("%s:%d: %ld.%09lds not after %ld.%09lds "
-           "(difference %ld.%09lds)n",
+    printf ("%s:%d: %jd.%09jds not after %jd.%09jds "
+           "(difference %jd.%09jds)n",
            file, line,
-           left.tv_sec, left.tv_nsec,
-           right.tv_sec, right.tv_nsec,
-           diff.tv_sec, diff.tv_nsec);
+           (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
+           (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
+           (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
   }
---
Florian Weimer May 10, 2019, 12:22 p.m. | #7
* Adhemerval Zanella:

> I will check the following patch to fix it:

>

> ---

> diff --git a/support/timespec.c b/support/timespec.c

> index f1b88c1f4c..653293970a 100644

> --- a/support/timespec.c

> +++ b/support/timespec.c

> @@ -18,6 +18,7 @@

>  

>  #include <support/timespec.h>

>  #include <stdio.h>

> +#include <stdint.h>

>  

>  void

>  test_timespec_before_impl (const char *file, int line,

> @@ -29,12 +30,12 @@ test_timespec_before_impl (const char *file, int line,

>           && left.tv_nsec > right.tv_nsec)) {

>      support_record_failure ();

>      const struct timespec diff = timespec_sub (left, right);

> -    printf ("%s:%d: %ld.%09lds not before %ld.%09lds "

> -           "(difference %ld.%09lds)n",

> +    printf ("%s:%d: %jd.%09jds not before %jd.%09jds "

> +           "(difference %jd.%09jds)n",

>             file, line,

> -           left.tv_sec, left.tv_nsec,

> -           right.tv_sec, right.tv_nsec,

> -           diff.tv_sec, diff.tv_nsec);

> +           (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,

> +           (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,

> +           (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);

>    }

>  }

>  

> @@ -48,11 +49,11 @@ test_timespec_equal_or_after_impl (const char *file, int line,

>           && left.tv_nsec < right.tv_nsec)) {

>      support_record_failure ();

>      const struct timespec diff = timespec_sub (right, left);

> -    printf ("%s:%d: %ld.%09lds not after %ld.%09lds "

> -           "(difference %ld.%09lds)n",

> +    printf ("%s:%d: %jd.%09jds not after %jd.%09jds "

> +           "(difference %jd.%09jds)n",

>             file, line,

> -           left.tv_sec, left.tv_nsec,

> -           right.tv_sec, right.tv_nsec,

> -           diff.tv_sec, diff.tv_nsec);

> +           (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,

> +           (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,

> +           (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);

>    }


Looks okay to me.

Thanks,
Florian

Patch

diff --git a/ChangeLog b/ChangeLog
index 6008265..cd0ef83 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,23 @@ 
 2019-05-02  Mike Crowe  <mac@mcrowe.com>
 
+	* support/timespec.h: New file. Provide timespec helper functions
+	along with macros in the style of those in check.h.
+
+	* support/timespec.c: New file. Implement check functions declared
+	in support/timespec.h.
+
+	* support/timespec-add.c: New file from gnulib containing
+	timespec_add implementation that handles overflow.
+
+	* support/timespec-sub.c: New file from gnulib containing
+	timespec_sub implementation that handles overflow.
+
+	* support/README: Mention timespec.h.
+
+	* nptl/tst-cond11.c: Use libsupport.
+
+2019-05-02  Mike Crowe  <mac@mcrowe.com>
+
 	* support/xclock_gettime.c (xclock_gettime): New file. Provide
 	clock_gettime wrapper for use in tests that fails the test rather
 	than returning failure.
diff --git a/nptl/tst-cond11.c b/nptl/tst-cond11.c
index 97a8bd0..3bc4ff4 100644
--- a/nptl/tst-cond11.c
+++ b/nptl/tst-cond11.c
@@ -21,6 +21,10 @@ 
 #include <stdio.h>
 #include <time.h>
 #include <unistd.h>
+#include <support/check.h>
+#include <support/timespec.h>
+#include <support/xthread.h>
+#include <support/xtime.h>
 
 
 #if defined _POSIX_CLOCK_SELECTION && _POSIX_CLOCK_SELECTION >= 0
@@ -34,132 +38,36 @@  run_test (clockid_t cl)
 
   printf ("clock = %d\n", (int) cl);
 
-  if (pthread_condattr_init (&condattr) != 0)
-    {
-      puts ("condattr_init failed");
-      return 1;
-    }
-
-  if (pthread_condattr_setclock (&condattr, cl) != 0)
-    {
-      puts ("condattr_setclock failed");
-      return 1;
-    }
+  TEST_COMPARE (pthread_condattr_init (&condattr), 0);
+  TEST_COMPARE (pthread_condattr_setclock (&condattr, cl), 0);
 
   clockid_t cl2;
-  if (pthread_condattr_getclock (&condattr, &cl2) != 0)
-    {
-      puts ("condattr_getclock failed");
-      return 1;
-    }
-  if (cl != cl2)
-    {
-      printf ("condattr_getclock returned wrong value: %d, expected %d\n",
-	      (int) cl2, (int) cl);
-      return 1;
-    }
-
-  if (pthread_cond_init (&cond, &condattr) != 0)
-    {
-      puts ("cond_init failed");
-      return 1;
-    }
-
-  if (pthread_condattr_destroy (&condattr) != 0)
-    {
-      puts ("condattr_destroy failed");
-      return 1;
-    }
-
-  if (pthread_mutexattr_init (&mutattr) != 0)
-    {
-      puts ("mutexattr_init failed");
-      return 1;
-    }
-
-  if (pthread_mutexattr_settype (&mutattr, PTHREAD_MUTEX_ERRORCHECK) != 0)
-    {
-      puts ("mutexattr_settype failed");
-      return 1;
-    }
-
-  if (pthread_mutex_init (&mut, &mutattr) != 0)
-    {
-      puts ("mutex_init failed");
-      return 1;
-    }
-
-  if (pthread_mutexattr_destroy (&mutattr) != 0)
-    {
-      puts ("mutexattr_destroy failed");
-      return 1;
-    }
-
-  if (pthread_mutex_lock (&mut) != 0)
-    {
-      puts ("mutex_lock failed");
-      return 1;
-    }
-
-  if (pthread_mutex_lock (&mut) != EDEADLK)
-    {
-      puts ("2nd mutex_lock did not return EDEADLK");
-      return 1;
-    }
-
-  struct timespec ts;
-  if (clock_gettime (cl, &ts) != 0)
-    {
-      puts ("clock_gettime failed");
-      return 1;
-    }
+  TEST_COMPARE (pthread_condattr_getclock (&condattr, &cl2), 0);
+  TEST_COMPARE (cl, cl2);
+
+  TEST_COMPARE (pthread_cond_init (&cond, &condattr), 0);
+  TEST_COMPARE (pthread_condattr_destroy (&condattr), 0);
+
+  xpthread_mutexattr_init (&mutattr);
+  xpthread_mutexattr_settype (&mutattr, PTHREAD_MUTEX_ERRORCHECK);
+  xpthread_mutex_init (&mut, &mutattr);
+  xpthread_mutexattr_destroy (&mutattr);
+
+  xpthread_mutex_lock (&mut);
+  TEST_COMPARE (pthread_mutex_lock (&mut), EDEADLK);
+
+  struct timespec ts_timeout;
+  xclock_gettime (cl, &ts_timeout);
 
   /* Wait one second.  */
-  ++ts.tv_sec;
-
-  int e = pthread_cond_timedwait (&cond, &mut, &ts);
-  if (e == 0)
-    {
-      puts ("cond_timedwait succeeded");
-      return 1;
-    }
-  else if (e != ETIMEDOUT)
-    {
-      puts ("cond_timedwait did not return ETIMEDOUT");
-      return 1;
-    }
-
-  struct timespec ts2;
-  if (clock_gettime (cl, &ts2) != 0)
-    {
-      puts ("second clock_gettime failed");
-      return 1;
-    }
-
-  if (ts2.tv_sec < ts.tv_sec
-      || (ts2.tv_sec == ts.tv_sec && ts2.tv_nsec < ts.tv_nsec))
-    {
-      puts ("timeout too short");
-      return 1;
-    }
-
-  if (pthread_mutex_unlock (&mut) != 0)
-    {
-      puts ("mutex_unlock failed");
-      return 1;
-    }
-
-  if (pthread_mutex_destroy (&mut) != 0)
-    {
-      puts ("mutex_destroy failed");
-      return 1;
-    }
-
-  if (pthread_cond_destroy (&cond) != 0)
-    {
-      puts ("cond_destroy failed");
-      return 1;
-    }
+  ++ts_timeout.tv_sec;
+
+  TEST_COMPARE (pthread_cond_timedwait (&cond, &mut, &ts_timeout), ETIMEDOUT);
+  TEST_TIMESPEC_BEFORE_NOW (ts_timeout, cl);
+
+  xpthread_mutex_unlock (&mut);
+  xpthread_mutex_destroy (&mut);
+  TEST_COMPARE (pthread_cond_destroy (&cond), 0);
 
   return 0;
 }
@@ -171,12 +79,11 @@  do_test (void)
 {
 #if !defined _POSIX_CLOCK_SELECTION || _POSIX_CLOCK_SELECTION == -1
 
-  puts ("_POSIX_CLOCK_SELECTION not supported, test skipped");
-  return 0;
+  FAIL_UNSUPPORTED ("_POSIX_CLOCK_SELECTION not supported, test skipped");
 
 #else
 
-  int res = run_test (CLOCK_REALTIME);
+  run_test (CLOCK_REALTIME);
 
 # if defined _POSIX_MONOTONIC_CLOCK && _POSIX_MONOTONIC_CLOCK >= 0
 #  if _POSIX_MONOTONIC_CLOCK == 0
@@ -184,20 +91,16 @@  do_test (void)
   if (e < 0)
     puts ("CLOCK_MONOTONIC not supported");
   else if (e == 0)
-    {
-      puts ("sysconf (_SC_MONOTONIC_CLOCK) must not return 0");
-      res = 1;
-    }
+      FAIL_RET ("sysconf (_SC_MONOTONIC_CLOCK) must not return 0");
   else
 #  endif
-    res |= run_test (CLOCK_MONOTONIC);
+    run_test (CLOCK_MONOTONIC);
 # else
   puts ("_POSIX_MONOTONIC_CLOCK not defined");
 # endif
 
-  return res;
+  return 0;
 #endif
 }
 
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
+#include <support/test-driver.c>
diff --git a/support/Makefile b/support/Makefile
index 05865fe..64044f6 100644
--- a/support/Makefile
+++ b/support/Makefile
@@ -71,6 +71,9 @@  libsupport-routines = \
   support_test_main \
   support_test_verify_impl \
   temp_file \
+  timespec \
+  timespec-add \
+  timespec-sub \
   write_message \
   xaccept \
   xaccept4 \
diff --git a/support/README b/support/README
index d82f472..ae2c41c 100644
--- a/support/README
+++ b/support/README
@@ -28,3 +28,8 @@  header files provide related declarations:
 * check.h
 * temp_file.h
 * test-driver.h
+
+For tests that make use of struct timespec, the following header files
+contain additional macros and helper functions:
+
+* timespec.h
diff --git a/support/timespec-add.c b/support/timespec-add.c
new file mode 100644
index 0000000..be7a590
--- /dev/null
+++ b/support/timespec-add.c
@@ -0,0 +1,71 @@ 
+/* Add two struct timespec values.
+   Copyright (C) 2011-2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library and is also part of gnulib.
+   Patches to this file should be submitted to both projects.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+/* Return the sum of two timespec values A and B.  On overflow, return
+   an extremal value.  This assumes 0 <= tv_nsec < TIMESPEC_HZ.  */
+
+#include <config.h>
+#include "timespec.h"
+
+#include "intprops.h"
+
+struct timespec
+timespec_add (struct timespec a, struct timespec b)
+{
+  time_t rs = a.tv_sec;
+  time_t bs = b.tv_sec;
+  int ns = a.tv_nsec + b.tv_nsec;
+  int nsd = ns - TIMESPEC_HZ;
+  int rns = ns;
+  time_t tmin = TYPE_MINIMUM (time_t);
+  time_t tmax = TYPE_MAXIMUM (time_t);
+
+  if (0 <= nsd)
+    {
+      rns = nsd;
+      if (bs < tmax)
+        bs++;
+      else if (rs < 0)
+        rs++;
+      else
+        goto high_overflow;
+    }
+
+  /* INT_ADD_WRAPV is not appropriate since time_t might be unsigned.
+     In theory time_t might be narrower than int, so plain
+     INT_ADD_OVERFLOW does not suffice.  */
+  if (! INT_ADD_OVERFLOW (rs, bs) && tmin <= rs + bs && rs + bs <= tmax)
+    rs += bs;
+  else
+    {
+      if (rs < 0)
+        {
+          rs = tmin;
+          rns = 0;
+        }
+      else
+        {
+        high_overflow:
+          rs = tmax;
+          rns = TIMESPEC_HZ - 1;
+        }
+    }
+
+  return make_timespec (rs, rns);
+}
diff --git a/support/timespec-sub.c b/support/timespec-sub.c
new file mode 100644
index 0000000..bf95c7f
--- /dev/null
+++ b/support/timespec-sub.c
@@ -0,0 +1,71 @@ 
+/* Subtract two struct timespec values.
+   Copyright (C) 2011-2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library and is also part of gnulib.
+   Patches to this file should be submitted to both projects.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+/* Return the difference between two timespec values A and B.  On
+   overflow, return an extremal value.  This assumes 0 <= tv_nsec <
+   TIMESPEC_HZ.  */
+
+#include <config.h>
+#include "timespec.h"
+
+#include "intprops.h"
+
+struct timespec
+timespec_sub (struct timespec a, struct timespec b)
+{
+  time_t rs = a.tv_sec;
+  time_t bs = b.tv_sec;
+  int ns = a.tv_nsec - b.tv_nsec;
+  int rns = ns;
+  time_t tmin = TYPE_MINIMUM (time_t);
+  time_t tmax = TYPE_MAXIMUM (time_t);
+
+  if (ns < 0)
+    {
+      rns = ns + TIMESPEC_HZ;
+      if (bs < tmax)
+        bs++;
+      else if (- TYPE_SIGNED (time_t) < rs)
+        rs--;
+      else
+        goto low_overflow;
+    }
+
+  /* INT_SUBTRACT_WRAPV is not appropriate since time_t might be unsigned.
+     In theory time_t might be narrower than int, so plain
+     INT_SUBTRACT_OVERFLOW does not suffice.  */
+  if (! INT_SUBTRACT_OVERFLOW (rs, bs) && tmin <= rs - bs && rs - bs <= tmax)
+    rs -= bs;
+  else
+    {
+      if (rs < 0)
+        {
+        low_overflow:
+          rs = tmin;
+          rns = 0;
+        }
+      else
+        {
+          rs = tmax;
+          rns = TIMESPEC_HZ - 1;
+        }
+    }
+
+  return make_timespec (rs, rns);
+}
diff --git a/support/timespec.c b/support/timespec.c
new file mode 100644
index 0000000..f1b88c1
--- /dev/null
+++ b/support/timespec.c
@@ -0,0 +1,58 @@ 
+/* Support code for timespec checks.
+   Copyright (C) 2019 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <support/timespec.h>
+#include <stdio.h>
+
+void
+test_timespec_before_impl (const char *file, int line,
+			   const struct timespec left,
+			   const struct timespec right)
+{
+  if (left.tv_sec > right.tv_sec
+      || (left.tv_sec == right.tv_sec
+	  && left.tv_nsec > right.tv_nsec)) {
+    support_record_failure ();
+    const struct timespec diff = timespec_sub (left, right);
+    printf ("%s:%d: %ld.%09lds not before %ld.%09lds "
+	    "(difference %ld.%09lds)n",
+	    file, line,
+	    left.tv_sec, left.tv_nsec,
+	    right.tv_sec, right.tv_nsec,
+	    diff.tv_sec, diff.tv_nsec);
+  }
+}
+
+void
+test_timespec_equal_or_after_impl (const char *file, int line,
+				   const struct timespec left,
+				   const struct timespec right)
+{
+  if (left.tv_sec < right.tv_sec
+      || (left.tv_sec == right.tv_sec
+	  && left.tv_nsec < right.tv_nsec)) {
+    support_record_failure ();
+    const struct timespec diff = timespec_sub (right, left);
+    printf ("%s:%d: %ld.%09lds not after %ld.%09lds "
+	    "(difference %ld.%09lds)n",
+	    file, line,
+	    left.tv_sec, left.tv_nsec,
+	    right.tv_sec, right.tv_nsec,
+	    diff.tv_sec, diff.tv_nsec);
+  }
+}
diff --git a/support/timespec.h b/support/timespec.h
new file mode 100644
index 0000000..4a8b341
--- /dev/null
+++ b/support/timespec.h
@@ -0,0 +1,79 @@ 
+/* Useful functions for tests that use struct timespec.
+   Copyright (C) 2019 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef SUPPORT_TIMESPEC_H
+#define SUPPORT_TIMESPEC_H
+
+#include <stdio.h>
+#include <time.h>
+#include <support/check.h>
+#include <support/xtime.h>
+
+struct timespec timespec_add (struct timespec, struct timespec)
+  __attribute__((const));
+struct timespec timespec_sub (struct timespec, struct timespec)
+  __attribute__((const));
+
+static inline struct timespec
+make_timespec (time_t s, long int ns)
+{
+  struct timespec r;
+  r.tv_sec = s;
+  r.tv_nsec = ns;
+  return r;
+}
+
+enum { TIMESPEC_HZ = 1000000000 };
+
+void test_timespec_before_impl (const char *file, int line,
+                                const struct timespec left,
+                                const struct timespec right);
+
+void test_timespec_equal_or_after_impl (const char *file, int line,
+                                        const struct timespec left,
+                                        const struct timespec right);
+
+/* Check that the timespec on the left represents a time before the
+   time on the right. */
+#define TEST_TIMESPEC_BEFORE(left, right)                               \
+  test_timespec_before_impl (__FILE__, __LINE__, (left), (right))
+
+#define TEST_TIMESPEC_BEFORE_NOW(left, clockid)                 \
+  ({                                                            \
+    struct timespec now;                                        \
+    const int saved_errno = errno;                              \
+    xclock_gettime ((clockid), &now);                           \
+    TEST_TIMESPEC_BEFORE ((left), now);                         \
+    errno = saved_errno;                                        \
+  })
+
+/* Check that the timespec on the left represents a after before the
+   time on the right. */
+#define TEST_TIMESPEC_EQUAL_OR_AFTER(left, right)                       \
+  test_timespec_equal_or_after_impl (__FILE__, __LINE__, left, right)
+
+#define TEST_TIMESPEC_NOW_OR_AFTER(clockid, right)              \
+  ({                                                            \
+    struct timespec now;                                        \
+    const int saved_errno = errno;                              \
+    xclock_gettime ((clockid), &now);                           \
+    TEST_TIMESPEC_EQUAL_OR_AFTER (now, (right));                \
+    errno = saved_errno;                                        \
+  })
+
+#endif /* SUPPORT_TIMESPEC_H */