52f82acb7b
See containerd/btrfs PR 40 and moby/moby PR 44761. (Thanks to [@]neersighted.) The containerd/btrfs library now requires headers from kernel 4.12 or newer: - https://github.com/torvalds/linux/blob/master/include/uapi/linux/btrfs.h - https://github.com/torvalds/linux/blob/master/include/uapi/linux/btrfs_tree.h These files are licensed under the GPL-2.0 WITH Linux-syscall-note, so it should be compatible with the Apache License 2.0. https://spdx.org/licenses/Linux-syscall-note.html The dependency on the kernel headers only affects users building from source. Users on older kernels may opt to not compile this library (`BUILDTAGS=no_btfs`), or to provide headers from a newer kernel. Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
67 lines
1.8 KiB
Go
67 lines
1.8 KiB
Go
// Copyright 2019 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.
|
|
|
|
package cpu
|
|
|
|
import (
|
|
"runtime"
|
|
)
|
|
|
|
// byteOrder is a subset of encoding/binary.ByteOrder.
|
|
type byteOrder interface {
|
|
Uint32([]byte) uint32
|
|
Uint64([]byte) uint64
|
|
}
|
|
|
|
type littleEndian struct{}
|
|
type bigEndian struct{}
|
|
|
|
func (littleEndian) Uint32(b []byte) uint32 {
|
|
_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
|
|
return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
|
|
}
|
|
|
|
func (littleEndian) Uint64(b []byte) uint64 {
|
|
_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
|
|
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
|
|
uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
|
|
}
|
|
|
|
func (bigEndian) Uint32(b []byte) uint32 {
|
|
_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
|
|
return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
|
|
}
|
|
|
|
func (bigEndian) Uint64(b []byte) uint64 {
|
|
_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
|
|
return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
|
|
uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
|
|
}
|
|
|
|
// hostByteOrder returns littleEndian on little-endian machines and
|
|
// bigEndian on big-endian machines.
|
|
func hostByteOrder() byteOrder {
|
|
switch runtime.GOARCH {
|
|
case "386", "amd64", "amd64p32",
|
|
"alpha",
|
|
"arm", "arm64",
|
|
"loong64",
|
|
"mipsle", "mips64le", "mips64p32le",
|
|
"nios2",
|
|
"ppc64le",
|
|
"riscv", "riscv64",
|
|
"sh":
|
|
return littleEndian{}
|
|
case "armbe", "arm64be",
|
|
"m68k",
|
|
"mips", "mips64", "mips64p32",
|
|
"ppc", "ppc64",
|
|
"s390", "s390x",
|
|
"shbe",
|
|
"sparc", "sparc64":
|
|
return bigEndian{}
|
|
}
|
|
panic("unknown architecture")
|
|
}
|