rootfs: remove unused functions

Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
This commit is contained in:
Akihiro Suda 2017-08-12 07:08:28 +00:00
parent ca9dec32de
commit 4e2337794c
3 changed files with 0 additions and 220 deletions

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@ -1,99 +0,0 @@
package rootfs
import (
"context"
"fmt"
"io/ioutil"
"os"
"github.com/containerd/containerd/log"
"github.com/containerd/containerd/mount"
"github.com/containerd/containerd/snapshot"
digest "github.com/opencontainers/go-digest"
"github.com/pkg/errors"
)
var (
initializers = map[string]initializerFunc{}
)
type initializerFunc func(string) error
type Mounter interface {
Mount(target string, mounts ...mount.Mount) error
Unmount(target string) error
}
func InitRootFS(ctx context.Context, name string, parent digest.Digest, readonly bool, snapshotter snapshot.Snapshotter, mounter Mounter) ([]mount.Mount, error) {
_, err := snapshotter.Stat(ctx, name)
if err == nil {
return nil, errors.Errorf("rootfs already exists")
}
// TODO: ensure not exist error once added to snapshot package
parentS := parent.String()
initName := defaultInitializer
initFn := initializers[initName]
if initFn != nil {
parentS, err = createInitLayer(ctx, parentS, initName, initFn, snapshotter, mounter)
if err != nil {
return nil, err
}
}
if readonly {
return snapshotter.View(ctx, name, parentS)
}
return snapshotter.Prepare(ctx, name, parentS)
}
func createInitLayer(ctx context.Context, parent, initName string, initFn func(string) error, snapshotter snapshot.Snapshotter, mounter Mounter) (string, error) {
initS := fmt.Sprintf("%s %s", parent, initName)
if _, err := snapshotter.Stat(ctx, initS); err == nil {
return initS, nil
}
// TODO: ensure not exist error once added to snapshot package
// Create tempdir
td, err := ioutil.TempDir("", "create-init-")
if err != nil {
return "", err
}
defer os.RemoveAll(td)
mounts, err := snapshotter.Prepare(ctx, td, parent)
if err != nil {
return "", err
}
defer func() {
if err != nil {
// TODO: once implemented uncomment
//if rerr := snapshotter.Remove(ctx, td); rerr != nil {
// log.G(ctx).Errorf("Failed to remove snapshot %s: %v", td, merr)
//}
}
}()
if err = mounter.Mount(td, mounts...); err != nil {
return "", err
}
if err = initFn(td); err != nil {
if merr := mounter.Unmount(td); merr != nil {
log.G(ctx).Errorf("Failed to unmount %s: %v", td, merr)
}
return "", err
}
if err = mounter.Unmount(td); err != nil {
return "", err
}
if err := snapshotter.Commit(ctx, initS, td); err != nil {
return "", err
}
return initS, nil
}

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@ -1,114 +0,0 @@
package rootfs
import (
"os"
"path/filepath"
"syscall"
)
const (
defaultInitializer = "linux-init"
)
func init() {
initializers[defaultInitializer] = initFS
}
func createDirectory(name string, uid, gid int) initializerFunc {
return func(root string) error {
dname := filepath.Join(root, name)
st, err := os.Stat(dname)
if err != nil && !os.IsNotExist(err) {
return err
} else if err == nil {
if st.IsDir() {
stat := st.Sys().(*syscall.Stat_t)
if int(stat.Gid) == gid && int(stat.Uid) == uid {
return nil
}
} else {
if err := os.Remove(dname); err != nil {
return err
}
if err := os.Mkdir(dname, 0755); err != nil {
return err
}
}
} else {
if err := os.Mkdir(dname, 0755); err != nil {
return err
}
}
return os.Chown(dname, uid, gid)
}
}
func touchFile(name string, uid, gid int) initializerFunc {
return func(root string) error {
fname := filepath.Join(root, name)
st, err := os.Stat(fname)
if err != nil && !os.IsNotExist(err) {
return err
} else if err == nil {
stat := st.Sys().(*syscall.Stat_t)
if int(stat.Gid) == gid && int(stat.Uid) == uid {
return nil
}
return os.Chown(fname, uid, gid)
}
f, err := os.OpenFile(fname, os.O_CREATE, 0644)
if err != nil {
return err
}
defer f.Close()
return f.Chown(uid, gid)
}
}
func symlink(oldname, newname string) initializerFunc {
return func(root string) error {
linkName := filepath.Join(root, newname)
if _, err := os.Stat(linkName); err != nil && !os.IsNotExist(err) {
return err
} else if err == nil {
return nil
}
return os.Symlink(oldname, linkName)
}
}
func initFS(root string) error {
st, err := os.Stat(root)
if err != nil {
return err
}
stat := st.Sys().(*syscall.Stat_t)
uid := int(stat.Uid)
gid := int(stat.Gid)
initFuncs := []initializerFunc{
createDirectory("/dev", uid, gid),
createDirectory("/dev/pts", uid, gid),
createDirectory("/dev/shm", uid, gid),
touchFile("/dev/console", uid, gid),
createDirectory("/proc", uid, gid),
createDirectory("/sys", uid, gid),
createDirectory("/etc", uid, gid),
touchFile("/etc/resolv.conf", uid, gid),
touchFile("/etc/hosts", uid, gid),
touchFile("/etc/hostname", uid, gid),
symlink("/proc/mounts", "/etc/mtab"),
}
for _, fn := range initFuncs {
if err := fn(root); err != nil {
return err
}
}
return nil
}

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@ -1,7 +0,0 @@
// +build !linux
package rootfs
const (
defaultInitializer = ""
)