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
// Functions to access/create device major and minor numbers matching the
6
// encoding used in NetBSD's sys/types.h header.
7

8
package unix
9

10
// Major returns the major component of a NetBSD device number.
11
func Major(dev uint64) uint32 {
12
	return uint32((dev & 0x000fff00) >> 8)
13
}
14

15
// Minor returns the minor component of a NetBSD device number.
16
func Minor(dev uint64) uint32 {
17
	minor := uint32((dev & 0x000000ff) >> 0)
18
	minor |= uint32((dev & 0xfff00000) >> 12)
19
	return minor
20
}
21

22
// Mkdev returns a NetBSD device number generated from the given major and minor
23
// components.
24
func Mkdev(major, minor uint32) uint64 {
25
	dev := (uint64(major) << 8) & 0x000fff00
26
	dev |= (uint64(minor) << 12) & 0xfff00000
27
	dev |= (uint64(minor) << 0) & 0x000000ff
28
	return dev
29
}
30

31