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moby--moby/daemon/volumes_linux.go
David Calavera bd9814f0db Allow to downgrade local volumes from > 1.7 to 1.6.
Signed-off-by: David Calavera <david.calavera@gmail.com>
2015-06-09 18:04:59 -07:00

119 lines
2.7 KiB
Go

// +build !windows
package daemon
import (
"os"
"path/filepath"
"sort"
"strings"
"github.com/docker/docker/daemon/execdriver"
"github.com/docker/docker/pkg/system"
"github.com/docker/docker/volume"
"github.com/docker/docker/volume/local"
)
// copyOwnership copies the permissions and uid:gid of the source file
// into the destination file
func copyOwnership(source, destination string) error {
stat, err := system.Stat(source)
if err != nil {
return err
}
if err := os.Chown(destination, int(stat.Uid()), int(stat.Gid())); err != nil {
return err
}
return os.Chmod(destination, os.FileMode(stat.Mode()))
}
func (container *Container) setupMounts() ([]execdriver.Mount, error) {
var mounts []execdriver.Mount
for _, m := range container.MountPoints {
path, err := m.Setup()
if err != nil {
return nil, err
}
mounts = append(mounts, execdriver.Mount{
Source: path,
Destination: m.Destination,
Writable: m.RW,
})
}
mounts = sortMounts(mounts)
return append(mounts, container.networkMounts()...), nil
}
func sortMounts(m []execdriver.Mount) []execdriver.Mount {
sort.Sort(mounts(m))
return m
}
type mounts []execdriver.Mount
func (m mounts) Len() int {
return len(m)
}
func (m mounts) Less(i, j int) bool {
return m.parts(i) < m.parts(j)
}
func (m mounts) Swap(i, j int) {
m[i], m[j] = m[j], m[i]
}
func (m mounts) parts(i int) int {
return len(strings.Split(filepath.Clean(m[i].Destination), string(os.PathSeparator)))
}
// migrateVolume links the contents of a volume created pre Docker 1.7
// into the location expected by the local driver.
// It creates a symlink from DOCKER_ROOT/vfs/dir/VOLUME_ID to DOCKER_ROOT/volumes/VOLUME_ID/_container_data.
// It preserves the volume json configuration generated pre Docker 1.7 to be able to
// downgrade from Docker 1.7 to Docker 1.6 without losing volume compatibility.
func migrateVolume(id, vfs string) error {
l, err := getVolumeDriver(volume.DefaultDriverName)
if err != nil {
return err
}
newDataPath := l.(*local.Root).DataPath(id)
fi, err := os.Stat(newDataPath)
if err != nil && !os.IsNotExist(err) {
return err
}
if fi != nil && fi.IsDir() {
return nil
}
return os.Symlink(vfs, newDataPath)
}
// validVolumeLayout checks whether the volume directory layout
// is valid to work with Docker post 1.7 or not.
func validVolumeLayout(files []os.FileInfo) bool {
if len(files) == 1 && files[0].Name() == local.VolumeDataPathName && files[0].IsDir() {
return true
}
if len(files) != 2 {
return false
}
for _, f := range files {
if f.Name() == "config.json" ||
(f.Name() == local.VolumeDataPathName && f.Mode()&os.ModeSymlink == os.ModeSymlink) {
// Old volume configuration, we ignore it
continue
}
return false
}
return true
}