replace sys Sequential funcs with moby/sys/sequential

These functions were originally copied from the docker / moby repository in
4a7a8efc2d. Migrating these functions to use the
github.com/moby/sys/sequential module allows them being shared between moby,
docker/cli, and containerd, and to allow using them without importing all of sys
which also depends on hcsshim and more.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn 2022-08-27 14:25:07 +02:00
parent bf8cdc2918
commit 93342d637c
No known key found for this signature in database
GPG Key ID: 76698F39D527CE8C
12 changed files with 490 additions and 110 deletions

View File

@ -23,7 +23,7 @@ import (
"os" "os"
"strings" "strings"
"github.com/containerd/containerd/sys" "github.com/moby/sys/sequential"
) )
// tarName returns platform-specific filepath // tarName returns platform-specific filepath
@ -57,15 +57,15 @@ func setHeaderForSpecialDevice(*tar.Header, string, os.FileInfo) error {
} }
func open(p string) (*os.File, error) { func open(p string) (*os.File, error) {
// We use sys.OpenSequential to ensure we use sequential file // We use sequential file access to avoid depleting the standby list on
// access on Windows to avoid depleting the standby list. // Windows.
return sys.OpenSequential(p) return sequential.Open(p)
} }
func openFile(name string, flag int, perm os.FileMode) (*os.File, error) { func openFile(name string, flag int, perm os.FileMode) (*os.File, error) {
// Source is regular file. We use sys.OpenFileSequential to use sequential // Source is regular file. We use sequential file access to avoid depleting
// file access to avoid depleting the standby list on Windows. // the standby list on Windows.
return sys.OpenFileSequential(name, flag, perm) return sequential.OpenFile(name, flag, perm)
} }
func mkdir(path string, perm os.FileMode) error { func mkdir(path string, perm os.FileMode) error {

1
go.mod
View File

@ -39,6 +39,7 @@ require (
github.com/klauspost/compress v1.15.9 github.com/klauspost/compress v1.15.9
github.com/moby/locker v1.0.1 github.com/moby/locker v1.0.1
github.com/moby/sys/mountinfo v0.6.2 github.com/moby/sys/mountinfo v0.6.2
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30
github.com/moby/sys/signal v0.7.0 github.com/moby/sys/signal v0.7.0
github.com/moby/sys/symlink v0.2.0 github.com/moby/sys/symlink v0.2.0
github.com/opencontainers/go-digest v1.0.0 github.com/opencontainers/go-digest v1.0.0

2
go.sum
View File

@ -687,6 +687,8 @@ github.com/moby/sys/mountinfo v0.4.1/go.mod h1:rEr8tzG/lsIZHBtN/JjGG+LMYx9eXgW2J
github.com/moby/sys/mountinfo v0.5.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdxbhnCLlSvSU= github.com/moby/sys/mountinfo v0.5.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdxbhnCLlSvSU=
github.com/moby/sys/mountinfo v0.6.2 h1:BzJjoreD5BMFNmD9Rus6gdd1pLuecOFPt8wC+Vygl78= github.com/moby/sys/mountinfo v0.6.2 h1:BzJjoreD5BMFNmD9Rus6gdd1pLuecOFPt8wC+Vygl78=
github.com/moby/sys/mountinfo v0.6.2/go.mod h1:IJb6JQeOklcdMU9F5xQ8ZALD+CUr5VlGpwtX+VE0rpI= github.com/moby/sys/mountinfo v0.6.2/go.mod h1:IJb6JQeOklcdMU9F5xQ8ZALD+CUr5VlGpwtX+VE0rpI=
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30 h1:LIL30sRWu2XhxsKr+Ek68J1zeaRatA+fv4UgX82P1+g=
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30/go.mod h1:tH2cOOs5V9MlPiXcQzRC+eEyab644PWKGRYaaV5ZZlo=
github.com/moby/sys/signal v0.6.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg= github.com/moby/sys/signal v0.6.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg=
github.com/moby/sys/signal v0.7.0 h1:25RW3d5TnQEoKvRbEKUGay6DCQ46IxAVTT9CUMgmsSI= github.com/moby/sys/signal v0.7.0 h1:25RW3d5TnQEoKvRbEKUGay6DCQ46IxAVTT9CUMgmsSI=
github.com/moby/sys/signal v0.7.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg= github.com/moby/sys/signal v0.7.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg=

View File

@ -45,6 +45,7 @@ require (
github.com/klauspost/compress v1.15.9 // indirect github.com/klauspost/compress v1.15.9 // indirect
github.com/moby/locker v1.0.1 // indirect github.com/moby/locker v1.0.1 // indirect
github.com/moby/sys/mountinfo v0.6.2 // indirect github.com/moby/sys/mountinfo v0.6.2 // indirect
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30 // indirect
github.com/moby/sys/signal v0.7.0 // indirect github.com/moby/sys/signal v0.7.0 // indirect
github.com/opencontainers/runc v1.1.4 // indirect github.com/opencontainers/runc v1.1.4 // indirect
github.com/opencontainers/runtime-tools v0.0.0-20190417131837-cd1349b7c47e // indirect github.com/opencontainers/runtime-tools v0.0.0-20190417131837-cd1349b7c47e // indirect

View File

@ -481,6 +481,8 @@ github.com/moby/sys/mountinfo v0.4.1/go.mod h1:rEr8tzG/lsIZHBtN/JjGG+LMYx9eXgW2J
github.com/moby/sys/mountinfo v0.5.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdxbhnCLlSvSU= github.com/moby/sys/mountinfo v0.5.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdxbhnCLlSvSU=
github.com/moby/sys/mountinfo v0.6.2 h1:BzJjoreD5BMFNmD9Rus6gdd1pLuecOFPt8wC+Vygl78= github.com/moby/sys/mountinfo v0.6.2 h1:BzJjoreD5BMFNmD9Rus6gdd1pLuecOFPt8wC+Vygl78=
github.com/moby/sys/mountinfo v0.6.2/go.mod h1:IJb6JQeOklcdMU9F5xQ8ZALD+CUr5VlGpwtX+VE0rpI= github.com/moby/sys/mountinfo v0.6.2/go.mod h1:IJb6JQeOklcdMU9F5xQ8ZALD+CUr5VlGpwtX+VE0rpI=
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30 h1:LIL30sRWu2XhxsKr+Ek68J1zeaRatA+fv4UgX82P1+g=
github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30/go.mod h1:tH2cOOs5V9MlPiXcQzRC+eEyab644PWKGRYaaV5ZZlo=
github.com/moby/sys/signal v0.7.0 h1:25RW3d5TnQEoKvRbEKUGay6DCQ46IxAVTT9CUMgmsSI= github.com/moby/sys/signal v0.7.0 h1:25RW3d5TnQEoKvRbEKUGay6DCQ46IxAVTT9CUMgmsSI=
github.com/moby/sys/signal v0.7.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg= github.com/moby/sys/signal v0.7.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg=
github.com/moby/sys/symlink v0.2.0/go.mod h1:7uZVF2dqJjG/NsClqul95CqKOBRQyYSNnJ6BMgR/gFs= github.com/moby/sys/symlink v0.2.0/go.mod h1:7uZVF2dqJjG/NsClqul95CqKOBRQyYSNnJ6BMgR/gFs=

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@ -0,0 +1,51 @@
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package sys
import (
"os"
"github.com/moby/sys/sequential"
)
// CreateSequential is deprecated.
//
// Deprecated: use github.com/moby/sys/sequential.Create
func CreateSequential(name string) (*os.File, error) {
return sequential.Create(name)
}
// OpenSequential is deprecated.
//
// Deprecated: use github.com/moby/sys/sequential.Open
func OpenSequential(name string) (*os.File, error) {
return sequential.Open(name)
}
// OpenFileSequential is deprecated.
//
// Deprecated: use github.com/moby/sys/sequential.OpenFile
func OpenFileSequential(name string, flag int, perm os.FileMode) (*os.File, error) {
return sequential.OpenFile(name, flag, perm)
}
// TempFileSequential is deprecated.
//
// Deprecated: use github.com/moby/sys/sequential.CreateTemp
func TempFileSequential(dir, prefix string) (f *os.File, err error) {
return sequential.CreateTemp(dir, prefix)
}

View File

@ -155,109 +155,6 @@ func IsAbs(path string) bool {
return true return true
} }
// The origin of the functions below here are the golang OS and windows packages,
// slightly modified to only cope with files, not directories due to the
// specific use case.
//
// The alteration is to allow a file on Windows to be opened with
// FILE_FLAG_SEQUENTIAL_SCAN (particular for docker load), to avoid eating
// the standby list, particularly when accessing large files such as layer.tar.
// CreateSequential creates the named file with mode 0666 (before umask), truncating
// it if it already exists. If successful, methods on the returned
// File can be used for I/O; the associated file descriptor has mode
// O_RDWR.
// If there is an error, it will be of type *PathError.
func CreateSequential(name string) (*os.File, error) {
return OpenFileSequential(name, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0)
}
// OpenSequential opens the named file for reading. If successful, methods on
// the returned file can be used for reading; the associated file
// descriptor has mode O_RDONLY.
// If there is an error, it will be of type *PathError.
func OpenSequential(name string) (*os.File, error) {
return OpenFileSequential(name, os.O_RDONLY, 0)
}
// OpenFileSequential is the generalized open call; most users will use Open
// or Create instead.
// If there is an error, it will be of type *PathError.
func OpenFileSequential(name string, flag int, _ os.FileMode) (*os.File, error) {
if name == "" {
return nil, &os.PathError{Op: "open", Path: name, Err: syscall.ENOENT}
}
r, errf := windowsOpenFileSequential(name, flag, 0)
if errf == nil {
return r, nil
}
return nil, &os.PathError{Op: "open", Path: name, Err: errf}
}
func windowsOpenFileSequential(name string, flag int, _ os.FileMode) (file *os.File, err error) {
r, e := windowsOpenSequential(name, flag|windows.O_CLOEXEC, 0)
if e != nil {
return nil, e
}
return os.NewFile(uintptr(r), name), nil
}
func makeInheritSa() *windows.SecurityAttributes {
var sa windows.SecurityAttributes
sa.Length = uint32(unsafe.Sizeof(sa))
sa.InheritHandle = 1
return &sa
}
func windowsOpenSequential(path string, mode int, _ uint32) (fd windows.Handle, err error) {
if len(path) == 0 {
return windows.InvalidHandle, windows.ERROR_FILE_NOT_FOUND
}
pathp, err := windows.UTF16PtrFromString(path)
if err != nil {
return windows.InvalidHandle, err
}
var access uint32
switch mode & (windows.O_RDONLY | windows.O_WRONLY | windows.O_RDWR) {
case windows.O_RDONLY:
access = windows.GENERIC_READ
case windows.O_WRONLY:
access = windows.GENERIC_WRITE
case windows.O_RDWR:
access = windows.GENERIC_READ | windows.GENERIC_WRITE
}
if mode&windows.O_CREAT != 0 {
access |= windows.GENERIC_WRITE
}
if mode&windows.O_APPEND != 0 {
access &^= windows.GENERIC_WRITE
access |= windows.FILE_APPEND_DATA
}
sharemode := uint32(windows.FILE_SHARE_READ | windows.FILE_SHARE_WRITE)
var sa *windows.SecurityAttributes
if mode&windows.O_CLOEXEC == 0 {
sa = makeInheritSa()
}
var createmode uint32
switch {
case mode&(windows.O_CREAT|windows.O_EXCL) == (windows.O_CREAT | windows.O_EXCL):
createmode = windows.CREATE_NEW
case mode&(windows.O_CREAT|windows.O_TRUNC) == (windows.O_CREAT | windows.O_TRUNC):
createmode = windows.CREATE_ALWAYS
case mode&windows.O_CREAT == windows.O_CREAT:
createmode = windows.OPEN_ALWAYS
case mode&windows.O_TRUNC == windows.O_TRUNC:
createmode = windows.TRUNCATE_EXISTING
default:
createmode = windows.OPEN_EXISTING
}
// Use FILE_FLAG_SEQUENTIAL_SCAN rather than FILE_ATTRIBUTE_NORMAL as implemented in golang.
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa363858(v=vs.85).aspx
const fileFlagSequentialScan = 0x08000000 // FILE_FLAG_SEQUENTIAL_SCAN
h, e := windows.CreateFile(pathp, access, sharemode, sa, createmode, fileFlagSequentialScan, 0)
return h, e
}
// ForceRemoveAll is the same as os.RemoveAll, but is aware of io.containerd.snapshotter.v1.windows // ForceRemoveAll is the same as os.RemoveAll, but is aware of io.containerd.snapshotter.v1.windows
// and uses hcsshim to unmount and delete container layers contained therein, in the correct order, // and uses hcsshim to unmount and delete container layers contained therein, in the correct order,
// when passed a containerd root data directory (i.e. the `--root` directory for containerd). // when passed a containerd root data directory (i.e. the `--root` directory for containerd).

202
vendor/github.com/moby/sys/sequential/LICENSE generated vendored Normal file
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@ -0,0 +1,202 @@
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15
vendor/github.com/moby/sys/sequential/doc.go generated vendored Normal file
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@ -0,0 +1,15 @@
// Package sequential provides a set of functions for managing sequential
// files on Windows.
//
// The origin of these functions are the golang OS and windows packages,
// slightly modified to only cope with files, not directories due to the
// specific use case.
//
// The alteration is to allow a file on Windows to be opened with
// FILE_FLAG_SEQUENTIAL_SCAN (particular for docker load), to avoid eating
// the standby list, particularly when accessing large files such as layer.tar.
//
// For non-Windows platforms, the package provides wrappers for the equivalents
// in the os packages. They are passthrough on Unix platforms, and only relevant
// on Windows.
package sequential

View File

@ -0,0 +1,45 @@
//go:build !windows
// +build !windows
package sequential
import "os"
// Create creates the named file with mode 0666 (before umask), truncating
// it if it already exists. If successful, methods on the returned
// File can be used for I/O; the associated file descriptor has mode
// O_RDWR.
// If there is an error, it will be of type *PathError.
func Create(name string) (*os.File, error) {
return os.Create(name)
}
// Open opens the named file for reading. If successful, methods on
// the returned file can be used for reading; the associated file
// descriptor has mode O_RDONLY.
// If there is an error, it will be of type *PathError.
func Open(name string) (*os.File, error) {
return os.Open(name)
}
// OpenFile is the generalized open call; most users will use Open
// or Create instead. It opens the named file with specified flag
// (O_RDONLY etc.) and perm, (0666 etc.) if applicable. If successful,
// methods on the returned File can be used for I/O.
// If there is an error, it will be of type *PathError.
func OpenFile(name string, flag int, perm os.FileMode) (*os.File, error) {
return os.OpenFile(name, flag, perm)
}
// CreateTemp creates a new temporary file in the directory dir
// with a name beginning with prefix, opens the file for reading
// and writing, and returns the resulting *os.File.
// If dir is the empty string, TempFile uses the default directory
// for temporary files (see os.TempDir).
// Multiple programs calling TempFile simultaneously
// will not choose the same file. The caller can use f.Name()
// to find the pathname of the file. It is the caller's responsibility
// to remove the file when no longer needed.
func CreateTemp(dir, prefix string) (f *os.File, err error) {
return os.CreateTemp(dir, prefix)
}

View File

@ -0,0 +1,161 @@
package sequential
import (
"os"
"path/filepath"
"strconv"
"sync"
"syscall"
"time"
"unsafe"
"golang.org/x/sys/windows"
)
// Create creates the named file with mode 0666 (before umask), truncating
// it if it already exists. If successful, methods on the returned
// File can be used for I/O; the associated file descriptor has mode
// O_RDWR.
// If there is an error, it will be of type *PathError.
func Create(name string) (*os.File, error) {
return OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0)
}
// Open opens the named file for reading. If successful, methods on
// the returned file can be used for reading; the associated file
// descriptor has mode O_RDONLY.
// If there is an error, it will be of type *PathError.
func Open(name string) (*os.File, error) {
return OpenFile(name, os.O_RDONLY, 0)
}
// OpenFile is the generalized open call; most users will use Open
// or Create instead.
// If there is an error, it will be of type *PathError.
func OpenFile(name string, flag int, _ os.FileMode) (*os.File, error) {
if name == "" {
return nil, &os.PathError{Op: "open", Path: name, Err: syscall.ENOENT}
}
r, err := openFileSequential(name, flag, 0)
if err == nil {
return r, nil
}
return nil, &os.PathError{Op: "open", Path: name, Err: err}
}
func openFileSequential(name string, flag int, _ os.FileMode) (file *os.File, err error) {
r, e := openSequential(name, flag|windows.O_CLOEXEC, 0)
if e != nil {
return nil, e
}
return os.NewFile(uintptr(r), name), nil
}
func makeInheritSa() *windows.SecurityAttributes {
var sa windows.SecurityAttributes
sa.Length = uint32(unsafe.Sizeof(sa))
sa.InheritHandle = 1
return &sa
}
func openSequential(path string, mode int, _ uint32) (fd windows.Handle, err error) {
if len(path) == 0 {
return windows.InvalidHandle, windows.ERROR_FILE_NOT_FOUND
}
pathp, err := windows.UTF16PtrFromString(path)
if err != nil {
return windows.InvalidHandle, err
}
var access uint32
switch mode & (windows.O_RDONLY | windows.O_WRONLY | windows.O_RDWR) {
case windows.O_RDONLY:
access = windows.GENERIC_READ
case windows.O_WRONLY:
access = windows.GENERIC_WRITE
case windows.O_RDWR:
access = windows.GENERIC_READ | windows.GENERIC_WRITE
}
if mode&windows.O_CREAT != 0 {
access |= windows.GENERIC_WRITE
}
if mode&windows.O_APPEND != 0 {
access &^= windows.GENERIC_WRITE
access |= windows.FILE_APPEND_DATA
}
sharemode := uint32(windows.FILE_SHARE_READ | windows.FILE_SHARE_WRITE)
var sa *windows.SecurityAttributes
if mode&windows.O_CLOEXEC == 0 {
sa = makeInheritSa()
}
var createmode uint32
switch {
case mode&(windows.O_CREAT|windows.O_EXCL) == (windows.O_CREAT | windows.O_EXCL):
createmode = windows.CREATE_NEW
case mode&(windows.O_CREAT|windows.O_TRUNC) == (windows.O_CREAT | windows.O_TRUNC):
createmode = windows.CREATE_ALWAYS
case mode&windows.O_CREAT == windows.O_CREAT:
createmode = windows.OPEN_ALWAYS
case mode&windows.O_TRUNC == windows.O_TRUNC:
createmode = windows.TRUNCATE_EXISTING
default:
createmode = windows.OPEN_EXISTING
}
// Use FILE_FLAG_SEQUENTIAL_SCAN rather than FILE_ATTRIBUTE_NORMAL as implemented in golang.
// https://msdn.microsoft.com/en-us/library/windows/desktop/aa363858(v=vs.85).aspx
const fileFlagSequentialScan = 0x08000000 // FILE_FLAG_SEQUENTIAL_SCAN
h, e := windows.CreateFile(pathp, access, sharemode, sa, createmode, fileFlagSequentialScan, 0)
return h, e
}
// Helpers for CreateTemp
var rand uint32
var randmu sync.Mutex
func reseed() uint32 {
return uint32(time.Now().UnixNano() + int64(os.Getpid()))
}
func nextSuffix() string {
randmu.Lock()
r := rand
if r == 0 {
r = reseed()
}
r = r*1664525 + 1013904223 // constants from Numerical Recipes
rand = r
randmu.Unlock()
return strconv.Itoa(int(1e9 + r%1e9))[1:]
}
// CreateTemp is a copy of os.CreateTemp, modified to use sequential
// file access. Below is the original comment from golang:
// TempFile creates a new temporary file in the directory dir
// with a name beginning with prefix, opens the file for reading
// and writing, and returns the resulting *os.File.
// If dir is the empty string, TempFile uses the default directory
// for temporary files (see os.TempDir).
// Multiple programs calling TempFile simultaneously
// will not choose the same file. The caller can use f.Name()
// to find the pathname of the file. It is the caller's responsibility
// to remove the file when no longer needed.
func CreateTemp(dir, prefix string) (f *os.File, err error) {
if dir == "" {
dir = os.TempDir()
}
nconflict := 0
for i := 0; i < 10000; i++ {
name := filepath.Join(dir, prefix+nextSuffix())
f, err = OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0o600)
if os.IsExist(err) {
if nconflict++; nconflict > 10 {
randmu.Lock()
rand = reseed()
randmu.Unlock()
}
continue
}
break
}
return
}

3
vendor/modules.txt vendored
View File

@ -300,6 +300,9 @@ github.com/moby/spdystream/spdy
# github.com/moby/sys/mountinfo v0.6.2 # github.com/moby/sys/mountinfo v0.6.2
## explicit; go 1.16 ## explicit; go 1.16
github.com/moby/sys/mountinfo github.com/moby/sys/mountinfo
# github.com/moby/sys/sequential v0.0.0-20220829095930-b22ba8a69b30
## explicit; go 1.17
github.com/moby/sys/sequential
# github.com/moby/sys/signal v0.7.0 # github.com/moby/sys/signal v0.7.0
## explicit; go 1.16 ## explicit; go 1.16
github.com/moby/sys/signal github.com/moby/sys/signal