usr/src/lib/libc/port/sys/timerfd.c

   1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11
  12 /*
  13  * Copyright (c) 2015, Joyent, Inc.  All rights reserved.
  14  */
  15
  16 #include <sys/timerfd.h>
  17 #include <sys/stat.h>
  18 #include <unistd.h>
  19 #include <errno.h>
  20 #include <fcntl.h>
  21
  22 int
  23 timerfd_create(int clockid, int flags)
  24 {
  25         int oflags = O_RDWR;
  26         int fd;
  27
  28         if (flags & ~(TFD_NONBLOCK | TFD_CLOEXEC)) {
  29                 errno = EINVAL;
  30                 return (-1);
  31         }
  32
  33         if (flags & TFD_NONBLOCK)
  34                 oflags |= O_NONBLOCK;
  35
  36         if (flags & TFD_CLOEXEC)
  37                 oflags |= O_CLOEXEC;
  38
  39         if ((fd = open("/dev/timerfd", oflags)) < 0)
  40                 return (-1);
  41
  42         if (ioctl(fd, TIMERFDIOC_CREATE, clockid) != 0) {
  43                 (void) close(fd);
  44                 return (-1);
  45         }
  46
  47         return (fd);
  48 }
  49
  50 int
  51 timerfd_settime(int fd, int flags, const struct itimerspec *new_value,
  52     struct itimerspec *old_value)
  53 {
  54         timerfd_settime_t st;
  55         int rval;
  56
  57         if (flags & ~(TFD_TIMER_ABSTIME | TFD_TIMER_CANCEL_ON_SET)) {
  58                 errno = EINVAL;
  59                 return (-1);
  60         }
  61
  62         st.tfd_settime_flags = flags;
  63         st.tfd_settime_value = (uint64_t)(uintptr_t)new_value;
  64         st.tfd_settime_ovalue = (uint64_t)(uintptr_t)old_value;
  65
  66         rval = ioctl(fd, TIMERFDIOC_SETTIME, &st);
  67
  68         if (rval == -1 && errno == ENOTTY) {
  69                 /*
  70                  * Linux has us return EINVAL when the file descriptor is valid
  71                  * but is not a timerfd file descriptor -- and LTP explicitly
  72                  * checks this case.
  73                  */
  74                 errno = EINVAL;
  75         }
  76
  77         return (rval);
  78 }
  79
  80 int
  81 timerfd_gettime(int fd, struct itimerspec *curr_value)
  82 {
  83         int rval = ioctl(fd, TIMERFDIOC_GETTIME, curr_value);
  84
  85         if (rval == -1 && errno == ENOTTY) {
  86                 /*
  87                  * See comment in timerfd_settime(), above.
  88                  */
  89                 errno = EINVAL;
  90         }
  91
  92         return (rval);
  93 }