forked from Deuxfleurs/bottin
30 lines
918 B
Go
30 lines
918 B
Go
|
// Copyright 2017 The Go Authors. All rights reserved.
|
||
|
|
// Use of this source code is governed by a BSD-style
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
// Functions to access/create device major and minor numbers matching the
|
||
|
|
// encoding used in OpenBSD's sys/types.h header.
|
||
|
|
|
||
|
|
package unix
|
||
|
|
|
||
|
|
// Major returns the major component of an OpenBSD device number.
|
||
|
|
func Major(dev uint64) uint32 {
|
||
|
|
return uint32((dev & 0x0000ff00) >> 8)
|
||
|
|
}
|
||
|
|
|
||
|
|
// Minor returns the minor component of an OpenBSD device number.
|
||
|
|
func Minor(dev uint64) uint32 {
|
||
|
|
minor := uint32((dev & 0x000000ff) >> 0)
|
||
|
|
minor |= uint32((dev & 0xffff0000) >> 8)
|
||
|
|
return minor
|
||
|
|
}
|
||
|
|
|
||
|
|
// Mkdev returns an OpenBSD device number generated from the given major and minor
|
||
|
|
// components.
|
||
|
|
func Mkdev(major, minor uint32) uint64 {
|
||
|
|
dev := (uint64(major) << 8) & 0x0000ff00
|
||
|
|
dev |= (uint64(minor) << 8) & 0xffff0000
|
||
|
|
dev |= (uint64(minor) << 0) & 0x000000ff
|
||
|
|
return dev
|
||
|
|
}
|