Files
sys/unix/dev_netbsd.go
Tobias Klauser 804a9fee62 unix: convert major/minor to uint64 before shifting in Mkdev on Darwin/*BSD
Follow CL 63090 and change the Makedev function on Darwin and *BSD to
convert to uint64 before shifting/masking. This avoids a potential
overflow.

Change-Id: I5b566329695cc5edcf82f0ff2366033011b0625b
Reviewed-on: https://go-review.googlesource.com/63112
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-12 19:57:40 +00:00

30 lines
913 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 NetBSD's sys/types.h header.
package unix
// Major returns the major component of a NetBSD device number.
func Major(dev uint64) uint32 {
return uint32((dev & 0x000fff00) >> 8)
}
// Minor returns the minor component of a NetBSD device number.
func Minor(dev uint64) uint32 {
minor := uint32((dev & 0x000000ff) >> 0)
minor |= uint32((dev & 0xfff00000) >> 12)
return minor
}
// Mkdev returns a NetBSD device number generated from the given major and minor
// components.
func Mkdev(major, minor uint32) uint64 {
dev := (uint64(major) << 8) & 0x000fff00
dev |= (uint64(minor) << 12) & 0xfff00000
dev |= (uint64(minor) << 0) & 0x000000ff
return dev
}