sysdeps/mach/htl/pt-timedblock.c

   1 /* Block a thread with a timeout.  Mach version.
   2    Copyright (C) 2000-2019 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 <assert.h>
  20 #include <errno.h>
  21 #include <time.h>
  22 #include <sys/time.h>
  23
  24 #include <mach.h>
  25 #include <mach/message.h>
  26
  27 #include <pt-internal.h>
  28
  29 /* Block THREAD.  */
  30 error_t
  31 __pthread_timedblock (struct __pthread *thread,
  32                       const struct timespec *abstime, clockid_t clock_id)
  33 {
  34   error_t err;
  35   mach_msg_header_t msg;
  36   mach_msg_timeout_t timeout;
  37   struct timespec now;
  38
  39   /* We have an absolute time and now we have to convert it to a
  40      relative time.  Arg.  */
  41
  42   err = clock_gettime (clock_id, &now);
  43   assert (!err);
  44
  45   if (now.tv_sec > abstime->tv_sec
  46       || (now.tv_sec == abstime->tv_sec && now.tv_nsec > abstime->tv_nsec))
  47     return ETIMEDOUT;
  48
  49   timeout = (abstime->tv_sec - now.tv_sec) * 1000;
  50
  51   if (abstime->tv_nsec >= now.tv_nsec)
  52     timeout += (abstime->tv_nsec - now.tv_nsec + 999999) / 1000000;
  53   else
  54     /* Need to do a carry.  */
  55     timeout -= (now.tv_nsec - abstime->tv_nsec + 999999) / 1000000;
  56
  57   err = __mach_msg (&msg, MACH_RCV_MSG | MACH_RCV_TIMEOUT, 0,
  58                     sizeof msg, thread->wakeupmsg.msgh_remote_port,
  59                     timeout, MACH_PORT_NULL);
  60   if (err == EMACH_RCV_TIMED_OUT)
  61     return ETIMEDOUT;
  62
  63   assert_perror (err);
  64   return 0;
  65 }