unix: add function for converting time.Time to Timespec
Add function TimeToTimespec for converting time.Time to Timespec.
Fixes golang/go#23078.
Change-Id: I685a4871d49131191f330b56b15bfd4f3131a9a5
Reviewed-on: https://go-review.googlesource.com/82919
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
diff --git a/unix/timestruct.go b/unix/timestruct.go
index 139fbbe..47b9011 100644
--- a/unix/timestruct.go
+++ b/unix/timestruct.go
@@ -6,6 +6,8 @@
package unix
+import "time"
+
// TimespecToNsec converts a Timespec value into a number of
// nanoseconds since the Unix epoch.
func TimespecToNsec(ts Timespec) int64 { return int64(ts.Sec)*1e9 + int64(ts.Nsec) }
@@ -22,6 +24,24 @@
return setTimespec(sec, nsec)
}
+// TimeToTimespec converts t into a Timespec.
+// On some 32-bit systems the range of valid Timespec values are smaller
+// than that of time.Time values. So if t is out of the valid range of
+// Timespec, it returns a zero Timespec and ERANGE.
+func TimeToTimespec(t time.Time) (Timespec, error) {
+ sec := t.Unix()
+ nsec := int64(t.Nanosecond())
+ ts := setTimespec(sec, nsec)
+
+ // Currently all targets have either int32 or int64 for Timespec.Sec.
+ // If there were a new target with floating point type for it, we have
+ // to consider the rounding error.
+ if int64(ts.Sec) != sec {
+ return Timespec{}, ERANGE
+ }
+ return ts, nil
+}
+
// TimevalToNsec converts a Timeval value into a number of nanoseconds
// since the Unix epoch.
func TimevalToNsec(tv Timeval) int64 { return int64(tv.Sec)*1e9 + int64(tv.Usec)*1e3 }
diff --git a/unix/timestruct_test.go b/unix/timestruct_test.go
new file mode 100644
index 0000000..4215f46
--- /dev/null
+++ b/unix/timestruct_test.go
@@ -0,0 +1,54 @@
+// Copyright 2017 The Go Authors. All right reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package unix_test
+
+import (
+ "testing"
+ "time"
+ "unsafe"
+
+ "golang.org/x/sys/unix"
+)
+
+func TestTimeToTimespec(t *testing.T) {
+ timeTests := []struct {
+ time time.Time
+ valid bool
+ }{
+ {time.Unix(0, 0), true},
+ {time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC), true},
+ {time.Date(2262, time.December, 31, 23, 0, 0, 0, time.UTC), false},
+ {time.Unix(0x7FFFFFFF, 0), true},
+ {time.Unix(0x80000000, 0), false},
+ {time.Unix(0x7FFFFFFF, 1000000000), false},
+ {time.Unix(0x7FFFFFFF, 999999999), true},
+ {time.Unix(-0x80000000, 0), true},
+ {time.Unix(-0x80000001, 0), false},
+ {time.Date(2038, time.January, 19, 3, 14, 7, 0, time.UTC), true},
+ {time.Date(2038, time.January, 19, 3, 14, 8, 0, time.UTC), false},
+ {time.Date(1901, time.December, 13, 20, 45, 52, 0, time.UTC), true},
+ {time.Date(1901, time.December, 13, 20, 45, 51, 0, time.UTC), false},
+ }
+
+ // Currently all targets have either int32 or int64 for Timespec.Sec.
+ // If there were a new target with unsigned or floating point type for
+ // it, this test must be adjusted.
+ have64BitTime := (unsafe.Sizeof(unix.Timespec{}.Sec) == 8)
+ for _, tt := range timeTests {
+ ts, err := unix.TimeToTimespec(tt.time)
+ tt.valid = tt.valid || have64BitTime
+ if tt.valid && err != nil {
+ t.Errorf("TimeToTimespec(%v): %v", tt.time, err)
+ }
+ if err == nil {
+ tstime := time.Unix(int64(ts.Sec), int64(ts.Nsec))
+ if !tstime.Equal(tt.time) {
+ t.Errorf("TimeToTimespec(%v) is the time %v", tt.time, tstime)
+ }
+ }
+ }
+}
