vendor/golang.org/x/sys/unix/timestruct.go

   1 // Copyright 2017 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
   6
   7 package unix
   8
   9 import "time"
  10
  11 // TimespecToNsec converts a Timespec value into a number of
  12 // nanoseconds since the Unix epoch.
  13 func TimespecToNsec(ts Timespec) int64 { return int64(ts.Sec)*1e9 + int64(ts.Nsec) }
  14
  15 // NsecToTimespec takes a number of nanoseconds since the Unix epoch
  16 // and returns the corresponding Timespec value.
  17 func NsecToTimespec(nsec int64) Timespec {
  18         sec := nsec / 1e9
  19         nsec = nsec % 1e9
  20         if nsec < 0 {
  21                 nsec += 1e9
  22                 sec--
  23         }
  24         return setTimespec(sec, nsec)
  25 }
  26
  27 // TimeToTimespec converts t into a Timespec.
  28 // On some 32-bit systems the range of valid Timespec values are smaller
  29 // than that of time.Time values.  So if t is out of the valid range of
  30 // Timespec, it returns a zero Timespec and ERANGE.
  31 func TimeToTimespec(t time.Time) (Timespec, error) {
  32         sec := t.Unix()
  33         nsec := int64(t.Nanosecond())
  34         ts := setTimespec(sec, nsec)
  35
  36         // Currently all targets have either int32 or int64 for Timespec.Sec.
  37         // If there were a new target with floating point type for it, we have
  38         // to consider the rounding error.
  39         if int64(ts.Sec) != sec {
  40                 return Timespec{}, ERANGE
  41         }
  42         return ts, nil
  43 }
  44
  45 // TimevalToNsec converts a Timeval value into a number of nanoseconds
  46 // since the Unix epoch.
  47 func TimevalToNsec(tv Timeval) int64 { return int64(tv.Sec)*1e9 + int64(tv.Usec)*1e3 }
  48
  49 // NsecToTimeval takes a number of nanoseconds since the Unix epoch
  50 // and returns the corresponding Timeval value.
  51 func NsecToTimeval(nsec int64) Timeval {
  52         nsec += 999 // round up to microsecond
  53         usec := nsec % 1e9 / 1e3
  54         sec := nsec / 1e9
  55         if usec < 0 {
  56                 usec += 1e6
  57                 sec--
  58         }
  59         return setTimeval(sec, usec)
  60 }
  61
  62 // Unix returns ts as the number of seconds and nanoseconds elapsed since the
  63 // Unix epoch.
  64 func (ts *Timespec) Unix() (sec int64, nsec int64) {
  65         return int64(ts.Sec), int64(ts.Nsec)
  66 }
  67
  68 // Unix returns tv as the number of seconds and nanoseconds elapsed since the
  69 // Unix epoch.
  70 func (tv *Timeval) Unix() (sec int64, nsec int64) {
  71         return int64(tv.Sec), int64(tv.Usec) * 1000
  72 }
  73
  74 // Nano returns ts as the number of nanoseconds elapsed since the Unix epoch.
  75 func (ts *Timespec) Nano() int64 {
  76         return int64(ts.Sec)*1e9 + int64(ts.Nsec)
  77 }
  78
  79 // Nano returns tv as the number of nanoseconds elapsed since the Unix epoch.
  80 func (tv *Timeval) Nano() int64 {
  81         return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
  82 }