sysdeps/mach/nanosleep.c

   1 /* nanosleep -- sleep for a period specified with a struct timespec
   2    Copyright (C) 2002-2013 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <mach.h>
  21 #include <sys/time.h>
  22 #include <unistd.h>
  23
  24 int
  25 __nanosleep (const struct timespec *requested_time,
  26              struct timespec *remaining)
  27 {
  28   mach_port_t recv;
  29   struct timeval before, after;
  30
  31   if (requested_time->tv_sec < 0
  32       || requested_time->tv_nsec < 0
  33       || requested_time->tv_nsec >= 1000000000)
  34     {
  35       errno = EINVAL;
  36       return -1;
  37     }
  38
  39   const mach_msg_timeout_t ms
  40     = requested_time->tv_sec * 1000
  41     + (requested_time->tv_nsec + 999999) / 1000000;
  42
  43   recv = __mach_reply_port ();
  44
  45   if (remaining && __gettimeofday (&before, NULL) < 0)
  46     return -1;
  47   error_t err = __mach_msg (NULL, MACH_RCV_MSG|MACH_RCV_TIMEOUT|MACH_RCV_INTERRUPT,
  48                             0, 0, recv, ms, MACH_PORT_NULL);
  49   __mach_port_destroy (mach_task_self (), recv);
  50   if (err == EMACH_RCV_INTERRUPTED)
  51     {
  52       if (remaining && __gettimeofday (&after, NULL) >= 0)
  53         {
  54           struct timeval req_time, elapsed, rem;
  55           TIMESPEC_TO_TIMEVAL (&req_time, requested_time);
  56           timersub (&after, &before, &elapsed);
  57           timersub (&req_time, &elapsed, &rem);
  58           TIMEVAL_TO_TIMESPEC (&rem, remaining);
  59         }
  60
  61       errno = EINTR;
  62       return -1;
  63     }
  64
  65   return 0;
  66 }
  67 libc_hidden_def (__nanosleep)
  68 weak_alias (__nanosleep, nanosleep)