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replace pkg/system Sequential funcs with moby/sys/sequential

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Migrating these functions to allow them being shared between moby, docker/cli,
and containerd, and to allow using them without importing all of sys / system,
which (in containerd) 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 13:50:37 +02:00
parent 18bb8fee3c
commit 509f19f611
No known key found for this signature in database
GPG key ID: 76698F39D527CE8C
13 changed files with 479 additions and 216 deletions
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7
image/tarexport/load.go
View file

@ -20,6 +20,7 @@ import (
"github.com/docker/docker/pkg/streamformatter"
"github.com/docker/docker/pkg/stringid"
"github.com/docker/docker/pkg/system"
"github.com/moby/sys/sequential"
"github.com/moby/sys/symlink"
"github.com/opencontainers/go-digest"
"github.com/sirupsen/logrus"
@ -168,9 +169,9 @@ func (l *tarexporter) setParentID(id, parentID image.ID) error {
}
func (l *tarexporter) loadLayer(filename string, rootFS image.RootFS, id string, foreignSrc distribution.Descriptor, progressOutput progress.Output) (layer.Layer, error) {
// We use system.OpenSequential to use sequential file access on Windows, avoiding
// depleting the standby list. On Linux, this equates to a regular os.Open.
rawTar, err := system.OpenSequential(filename)
// We use sequential file access to avoid depleting the standby list on Windows.
// On Linux, this equates to a regular os.Open.
rawTar, err := sequential.Open(filename)
if err != nil {
logrus.Debugf("Error reading embedded tar: %v", err)
return nil, err

8
image/tarexport/save.go
View file

@ -16,6 +16,7 @@ import (
"github.com/docker/docker/layer"
"github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/system"
"github.com/moby/sys/sequential"
"github.com/opencontainers/go-digest"
"github.com/pkg/errors"
)
@ -377,10 +378,9 @@ func (s *saveSession) saveLayer(id layer.ChainID, legacyImg image.V1Image, creat
return distribution.Descriptor{}, errors.Wrap(err, "error creating symlink while saving layer")
}
} else {
// Use system.CreateSequential rather than os.Create. This ensures sequential
// file access on Windows to avoid eating into MM standby list.
// On Linux, this equates to a regular os.Create.
tarFile, err := system.CreateSequential(layerPath)
// We use sequential file access to avoid depleting the standby list on
// Windows. On Linux, this equates to a regular os.Create.
tarFile, err := sequential.Create(layerPath)
if err != nil {
return distribution.Descriptor{}, err
}

15
pkg/archive/archive.go
View file

@ -25,6 +25,7 @@ import (
"github.com/docker/docker/pkg/pools"
"github.com/docker/docker/pkg/system"
"github.com/klauspost/compress/zstd"
"github.com/moby/sys/sequential"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
exec "golang.org/x/sys/execabs"
@ -660,10 +661,9 @@ func (ta *tarAppender) addTarFile(path, name string) error {
}
if hdr.Typeflag == tar.TypeReg && hdr.Size > 0 {
// We use system.OpenSequential to ensure we use sequential file
// access on Windows to avoid depleting the standby list.
// On Linux, this equates to a regular os.Open.
file, err := system.OpenSequential(path)
// We use sequential file access to avoid depleting the standby list on
// Windows. On Linux, this equates to a regular os.Open.
file, err := sequential.Open(path)
if err != nil {
return err
}
@ -701,10 +701,9 @@ func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, L
}
case tar.TypeReg, tar.TypeRegA:
// Source is regular file. We use system.OpenFileSequential to use sequential
// file access to avoid depleting the standby list on Windows.
// On Linux, this equates to a regular os.OpenFile
file, err := system.OpenFileSequential(path, os.O_CREATE|os.O_WRONLY, hdrInfo.Mode())
// Source is regular file. We use sequential file access to avoid depleting
// the standby list on Windows. On Linux, this equates to a regular os.OpenFile.
file, err := sequential.OpenFile(path, os.O_CREATE|os.O_WRONLY, hdrInfo.Mode())
if err != nil {
return err
}

35
pkg/system/filesys_deprecated.go Normal file
View file

@ -0,0 +1,35 @@
package system
import (
"os"
"github.com/moby/sys/sequential"
)
// CreateSequential is deprecated.
//
// Deprecated: use os.Create or github.com/moby/sys/sequential.Create()
func CreateSequential(name string) (*os.File, error) {
return sequential.Create(name)
}
// OpenSequential is deprecated.
//
// Deprecated: use os.Open or 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 os.CreateTemp or github.com/moby/sys/sequential.CreateTemp
func TempFileSequential(dir, prefix string) (f *os.File, err error) {
return sequential.CreateTemp(dir, prefix)
}

42
pkg/system/filesys_unix.go
View file

@ -15,45 +15,3 @@ func MkdirAllWithACL(path string, perm os.FileMode, sddl string) error {
func MkdirAll(path string, perm os.FileMode) error {
return os.MkdirAll(path, perm)
}
// The functions below here are wrappers for the equivalents in the os and ioutils packages.
// They are passthrough on Unix platforms, and only relevant on Windows.
// 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 os.Create(name)
}
// 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 os.Open(name)
}
// OpenFileSequential 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 OpenFileSequential(name string, flag int, perm os.FileMode) (*os.File, error) {
return os.OpenFile(name, flag, perm)
}
// TempFileSequential 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 TempFileSequential(dir, prefix string) (f *os.File, err error) {
return os.CreateTemp(dir, prefix)
}

159
pkg/system/filesys_windows.go
View file

@ -2,12 +2,8 @@ package system // import "github.com/docker/docker/pkg/system"
import (
"os"
"path/filepath"
"regexp"
"strconv"
"sync"
"syscall"
"time"
"unsafe"
"golang.org/x/sys/windows"
@ -120,158 +116,3 @@ func mkdirWithACL(name string, sddl string) error {
}
return nil
}
// 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
}
// Helpers for TempFileSequential
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:]
}
// TempFileSequential 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 TempFileSequential(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 = OpenFileSequential(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
if os.IsExist(err) {
if nconflict++; nconflict > 10 {
randmu.Lock()
rand = reseed()
randmu.Unlock()
}
continue
}
break
}
return
}

1
vendor.mod
View file

@ -56,6 +56,7 @@ require (
github.com/moby/swarmkit/v2 v2.0.0-20220721174824-48dd89375d0a
github.com/moby/sys/mount v0.3.3
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/symlink v0.2.0
github.com/moby/term v0.0.0-20210619224110-3f7ff695adc6

2
vendor.sum
View file

@ -770,6 +770,8 @@ github.com/moby/sys/mountinfo v0.5.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdx
github.com/moby/sys/mountinfo v0.6.0/go.mod h1:3bMD3Rg+zkqx8MRYPi7Pyb0Ie97QEBmdxbhnCLlSvSU=
github.com/moby/sys/mountinfo v0.6.2 h1:BzJjoreD5BMFNmD9Rus6gdd1pLuecOFPt8wC+Vygl78=
github.com/moby/sys/mountinfo v0.6.2/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 v0.7.0 h1:25RW3d5TnQEoKvRbEKUGay6DCQ46IxAVTT9CUMgmsSI=
github.com/moby/sys/signal v0.7.0/go.mod h1:GQ6ObYZfqacOwTtlXvcmh9A26dVRul/hbOZn88Kg8Tg=

202
vendor/github.com/moby/sys/sequential/LICENSE generated vendored Normal file
View file

@ -0,0 +1,202 @@
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15
vendor/github.com/moby/sys/sequential/doc.go generated vendored Normal file
View file

@ -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

45
vendor/github.com/moby/sys/sequential/sequential_unix.go generated vendored Normal file
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)
}

161
vendor/github.com/moby/sys/sequential/sequential_windows.go generated vendored Normal file
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

@ -667,6 +667,9 @@ github.com/moby/sys/mount
# github.com/moby/sys/mountinfo v0.6.2
## explicit; go 1.16
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
## explicit; go 1.16
github.com/moby/sys/signal