Refactor pkg/archive with a platform-independent stat struct

pkg/archive contains code both invoked from cli (cross platform) and
daemon (linux only) and Unix-specific dependencies break compilation on
Windows. We extracted those stat-related funcs into platform specific
implementations at pkg/system and added unit tests.

Signed-off-by: Ahmet Alp Balkan <ahmetb@microsoft.com>
This commit is contained in:
Ahmet Alp Balkan 2014-11-13 12:36:05 -08:00
parent 515e7481de
commit 718066ad61
13 changed files with 209 additions and 65 deletions

View file

@ -192,20 +192,11 @@ func (ta *tarAppender) addTarFile(path, name string) error {
hdr.Name = name
var (
nlink uint32
inode uint64
)
if stat, ok := fi.Sys().(*syscall.Stat_t); ok {
nlink = uint32(stat.Nlink)
inode = uint64(stat.Ino)
// Currently go does not fill in the major/minors
if stat.Mode&syscall.S_IFBLK == syscall.S_IFBLK ||
stat.Mode&syscall.S_IFCHR == syscall.S_IFCHR {
hdr.Devmajor = int64(major(uint64(stat.Rdev)))
hdr.Devminor = int64(minor(uint64(stat.Rdev)))
}
nlink, inode, err := setHeaderForSpecialDevice(hdr, ta, name, fi.Sys())
if err != nil {
return err
}
// if it's a regular file and has more than 1 link,
// it's hardlinked, so set the type flag accordingly
if fi.Mode().IsRegular() && nlink > 1 {
@ -291,7 +282,7 @@ func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, L
mode |= syscall.S_IFIFO
}
if err := syscall.Mknod(path, mode, int(system.Mkdev(hdr.Devmajor, hdr.Devminor))); err != nil {
if err := system.Mknod(path, mode, int(system.Mkdev(hdr.Devmajor, hdr.Devminor))); err != nil {
return err
}

39
archive/archive_unix.go Normal file
View file

@ -0,0 +1,39 @@
// +build !windows
package archive
import (
"errors"
"syscall"
"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
)
func setHeaderForSpecialDevice(hdr *tar.Header, ta *tarAppender, name string, stat interface{}) (nlink uint32, inode uint64, err error) {
s, ok := stat.(*syscall.Stat_t)
if !ok {
err = errors.New("cannot convert stat value to syscall.Stat_t")
return
}
nlink = uint32(s.Nlink)
inode = uint64(s.Ino)
// Currently go does not fil in the major/minors
if s.Mode&syscall.S_IFBLK == syscall.S_IFBLK ||
s.Mode&syscall.S_IFCHR == syscall.S_IFCHR {
hdr.Devmajor = int64(major(uint64(s.Rdev)))
hdr.Devminor = int64(minor(uint64(s.Rdev)))
}
return
}
func major(device uint64) uint64 {
return (device >> 8) & 0xfff
}
func minor(device uint64) uint64 {
return (device & 0xff) | ((device >> 12) & 0xfff00)
}

View file

@ -0,0 +1,12 @@
// +build windows
package archive
import (
"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
)
func setHeaderForSpecialDevice(hdr *tar.Header, ta *tarAppender, name string, stat interface{}) (nlink uint32, inode uint64, err error) {
// do nothing. no notion of Rdev, Inode, Nlink in stat on Windows
return
}

View file

@ -135,7 +135,7 @@ func Changes(layers []string, rw string) ([]Change, error) {
type FileInfo struct {
parent *FileInfo
name string
stat syscall.Stat_t
stat *system.Stat
children map[string]*FileInfo
capability []byte
added bool
@ -168,7 +168,7 @@ func (info *FileInfo) path() string {
}
func (info *FileInfo) isDir() bool {
return info.parent == nil || info.stat.Mode&syscall.S_IFDIR == syscall.S_IFDIR
return info.parent == nil || info.stat.Mode()&syscall.S_IFDIR == syscall.S_IFDIR
}
func (info *FileInfo) addChanges(oldInfo *FileInfo, changes *[]Change) {
@ -199,21 +199,21 @@ func (info *FileInfo) addChanges(oldInfo *FileInfo, changes *[]Change) {
oldChild, _ := oldChildren[name]
if oldChild != nil {
// change?
oldStat := &oldChild.stat
newStat := &newChild.stat
oldStat := oldChild.stat
newStat := newChild.stat
// Note: We can't compare inode or ctime or blocksize here, because these change
// when copying a file into a container. However, that is not generally a problem
// because any content change will change mtime, and any status change should
// be visible when actually comparing the stat fields. The only time this
// breaks down is if some code intentionally hides a change by setting
// back mtime
if oldStat.Mode != newStat.Mode ||
oldStat.Uid != newStat.Uid ||
oldStat.Gid != newStat.Gid ||
oldStat.Rdev != newStat.Rdev ||
if oldStat.Mode() != newStat.Mode() ||
oldStat.Uid() != newStat.Uid() ||
oldStat.Gid() != newStat.Gid() ||
oldStat.Rdev() != newStat.Rdev() ||
// Don't look at size for dirs, its not a good measure of change
(oldStat.Size != newStat.Size && oldStat.Mode&syscall.S_IFDIR != syscall.S_IFDIR) ||
!sameFsTimeSpec(system.GetLastModification(oldStat), system.GetLastModification(newStat)) ||
(oldStat.Size() != newStat.Size() && oldStat.Mode()&syscall.S_IFDIR != syscall.S_IFDIR) ||
!sameFsTimeSpec(oldStat.Mtim(), newStat.Mtim()) ||
bytes.Compare(oldChild.capability, newChild.capability) != 0 {
change := Change{
Path: newChild.path(),
@ -269,14 +269,6 @@ func newRootFileInfo() *FileInfo {
return root
}
func lstat(path string) (*stat, error) {
s, err := system.Lstat(path)
if err != nil {
return nil, err
}
return fromStatT(s), nil
}
func collectFileInfo(sourceDir string) (*FileInfo, error) {
root := newRootFileInfo()
@ -307,7 +299,7 @@ func collectFileInfo(sourceDir string) (*FileInfo, error) {
parent: parent,
}
s, err := lstat(path)
s, err := system.Lstat(path)
if err != nil {
return err
}
@ -369,14 +361,6 @@ func ChangesSize(newDir string, changes []Change) int64 {
return size
}
func major(device uint64) uint64 {
return (device >> 8) & 0xfff
}
func minor(device uint64) uint64 {
return (device & 0xff) | ((device >> 12) & 0xfff00)
}
// ExportChanges produces an Archive from the provided changes, relative to dir.
func ExportChanges(dir string, changes []Change) (Archive, error) {
reader, writer := io.Pipe()

View file

@ -12,16 +12,21 @@ import (
"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
"github.com/docker/docker/pkg/pools"
"github.com/docker/docker/pkg/system"
)
// ApplyLayer parses a diff in the standard layer format from `layer`, and
// applies it to the directory `dest`.
func ApplyLayer(dest string, layer ArchiveReader) error {
// We need to be able to set any perms
oldmask := syscall.Umask(0)
defer syscall.Umask(oldmask)
oldmask, err := system.Umask(0)
if err != nil {
return err
}
layer, err := DecompressStream(layer)
defer system.Umask(oldmask) // ignore err, ErrNotSupportedPlatform
layer, err = DecompressStream(layer)
if err != nil {
return err
}