(root)/
glibc-2.38/
support/
timespec.c
       1  /* Support code for timespec checks.
       2     Copyright (C) 2019-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <support/timespec.h>
      20  #include <stdio.h>
      21  #include <stdint.h>
      22  #include <assert.h>
      23  #include <intprops.h>
      24  
      25  void
      26  test_timespec_before_impl (const char *file, int line, struct timespec left,
      27  			   struct timespec right)
      28  {
      29    if (left.tv_sec > right.tv_sec
      30        || (left.tv_sec == right.tv_sec
      31  	  && left.tv_nsec > right.tv_nsec)) {
      32      support_record_failure ();
      33      const struct timespec diff = timespec_sub (left, right);
      34      printf ("%s:%d: %jd.%09jds not before %jd.%09jds "
      35  	    "(difference %jd.%09jds)\n",
      36  	    file, line,
      37  	    (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
      38  	    (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
      39  	    (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
      40    }
      41  }
      42  
      43  void
      44  test_timespec_equal_or_after_impl (const char *file, int line,
      45  				   struct timespec left,
      46  				   struct timespec right)
      47  {
      48    if (left.tv_sec < right.tv_sec
      49        || (left.tv_sec == right.tv_sec
      50  	  && left.tv_nsec < right.tv_nsec)) {
      51      support_record_failure ();
      52      const struct timespec diff = timespec_sub (right, left);
      53      printf ("%s:%d: %jd.%09jds not after %jd.%09jds "
      54  	    "(difference %jd.%09jds)\n",
      55  	    file, line,
      56  	    (intmax_t) left.tv_sec, (intmax_t) left.tv_nsec,
      57  	    (intmax_t) right.tv_sec, (intmax_t) right.tv_nsec,
      58  	    (intmax_t) diff.tv_sec, (intmax_t) diff.tv_nsec);
      59    }
      60  }
      61  
      62  /* Convert TIME to nanoseconds stored in a time_t.
      63     Returns time_t maximum or minimum if the conversion overflows
      64     or underflows, respectively.  */
      65  time_t
      66  support_timespec_ns (struct timespec time)
      67  {
      68    time_t time_ns;
      69    if (INT_MULTIPLY_WRAPV(time.tv_sec, TIMESPEC_HZ, &time_ns))
      70      return time.tv_sec < 0 ? TYPE_MINIMUM(time_t) : TYPE_MAXIMUM(time_t);
      71    if (INT_ADD_WRAPV(time_ns, time.tv_nsec, &time_ns))
      72      return time.tv_nsec < 0 ? TYPE_MINIMUM(time_t) : TYPE_MAXIMUM(time_t);
      73    return time_ns;
      74  }
      75  
      76  /* Returns time normalized timespec with .tv_nsec < TIMESPEC_HZ
      77     and the whole seconds  added to .tv_sec. If an overflow or
      78     underflow occurs the values are clamped to its maximum or
      79     minimum respectively.  */
      80  struct timespec
      81  support_timespec_normalize (struct timespec time)
      82  {
      83    struct timespec norm;
      84    if (INT_ADD_WRAPV (time.tv_sec, (time.tv_nsec / TIMESPEC_HZ), &norm.tv_sec))
      85     {
      86       norm.tv_sec = (time.tv_nsec < 0) ? TYPE_MINIMUM (time_t): TYPE_MAXIMUM (time_t);
      87       norm.tv_nsec = (time.tv_nsec < 0) ? -1 * (TIMESPEC_HZ - 1) : TIMESPEC_HZ - 1;
      88       return norm;
      89     }
      90    norm.tv_nsec = time.tv_nsec % TIMESPEC_HZ;
      91    return norm;
      92  }
      93  
      94  /* Returns TRUE if the observed time is within the given percentage
      95     bounds of the expected time, and FALSE otherwise.
      96     For example the call
      97  
      98     support_timespec_check_in_range(expected, observed, 0.5, 1.2);
      99  
     100     will check if
     101  
     102     0.5 of expected <= observed <= 1.2 of expected
     103  
     104     In other words it will check if observed time is within 50% to
     105     120% of the expected time.  */
     106  int
     107  support_timespec_check_in_range (struct timespec expected, struct timespec observed,
     108  			      double lower_bound, double upper_bound)
     109  {
     110    assert (upper_bound >= lower_bound);
     111    time_t expected_norm, observed_norm;
     112    expected_norm = support_timespec_ns (expected);
     113    /* Don't divide by zero  */
     114    assert(expected_norm != 0);
     115    observed_norm = support_timespec_ns (observed);
     116    double ratio = (double)observed_norm / expected_norm;
     117    return (lower_bound <= ratio && ratio <= upper_bound);
     118  }