sysdeps/mach/usleep.c

   1 /* Copyright (C) 1992-2017 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
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <mach.h>
  20 #include <sys/time.h>
  21 #include <unistd.h>
  22
  23 /* Sleep USECONDS microseconds, or until a previously set timer goes off.  */
  24 int
  25 usleep (useconds_t useconds)
  26 {
  27   mach_port_t recv;
  28   struct timeval before, after;
  29
  30   recv = __mach_reply_port ();
  31
  32   if (__gettimeofday (&before, NULL) < 0)
  33     return -1;
  34   (void) __mach_msg (NULL, MACH_RCV_MSG|MACH_RCV_TIMEOUT|MACH_RCV_INTERRUPT,
  35                      0, 0, recv, (useconds + 999) / 1000, MACH_PORT_NULL);
  36   __mach_port_destroy (mach_task_self (), recv);
  37   if (__gettimeofday (&after, NULL) < 0)
  38     return -1;
  39
  40   return 0;
  41 }