1  /* Copyright (C) 2000-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public License as
       6     published by the Free Software Foundation; either version 2.1 of the
       7     License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; see the file COPYING.LIB.  If
      16     not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <pthread.h>
      20  #include <time.h>
      21  
      22  #include "posix-timer.h"
      23  
      24  
      25  /* Get current value of timer TIMERID and store it in VALUE.  */
      26  int
      27  timer_gettime (timer_t timerid, struct itimerspec *value)
      28  {
      29    struct timer_node *timer;
      30    struct timespec now, expiry;
      31    int retval = -1, armed = 0, valid;
      32    clock_t clock = 0;
      33  
      34    pthread_mutex_lock (&__timer_mutex);
      35  
      36    timer = timer_id2ptr (timerid);
      37    valid = timer_valid (timer);
      38  
      39    if (valid) {
      40      armed = timer->armed;
      41      expiry = timer->expirytime;
      42      clock = timer->clock;
      43      value->it_interval = timer->value.it_interval;
      44    }
      45  
      46    pthread_mutex_unlock (&__timer_mutex);
      47  
      48    if (valid)
      49      {
      50        if (armed)
      51  	{
      52  	  __clock_gettime (clock, &now);
      53  	  if (timespec_compare (&now, &expiry) < 0)
      54  	    timespec_sub (&value->it_value, &expiry, &now);
      55  	  else
      56  	    {
      57  	      value->it_value.tv_sec = 0;
      58  	      value->it_value.tv_nsec = 0;
      59  	    }
      60  	}
      61        else
      62  	{
      63  	  value->it_value.tv_sec = 0;
      64  	  value->it_value.tv_nsec = 0;
      65  	}
      66  
      67        retval = 0;
      68      }
      69    else
      70      __set_errno (EINVAL);
      71  
      72    return retval;
      73  }