Move console into its own package

Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)

libcontainer/console/console.go

@@ -0,0 +1,46 @@
+// +build linux
+
+package console
+
+import (
+	"fmt"
+	"github.com/dotcloud/docker/pkg/label"
+	"github.com/dotcloud/docker/pkg/system"
+	"os"
+	"path/filepath"
+	"syscall"
+)
+
+// Setup initializes the proper /dev/console inside the rootfs path
+func Setup(rootfs, consolePath, mountLabel string) error {
+	oldMask := system.Umask(0000)
+	defer system.Umask(oldMask)
+
+	stat, err := os.Stat(consolePath)
+	if err != nil {
+		return fmt.Errorf("stat console %s %s", consolePath, err)
+	}
+	var (
+		st   = stat.Sys().(*syscall.Stat_t)
+		dest = filepath.Join(rootfs, "dev/console")
+	)
+	if err := os.Remove(dest); err != nil && !os.IsNotExist(err) {
+		return fmt.Errorf("remove %s %s", dest, err)
+	}
+	if err := os.Chmod(consolePath, 0600); err != nil {
+		return err
+	}
+	if err := os.Chown(consolePath, 0, 0); err != nil {
+		return err
+	}
+	if err := system.Mknod(dest, (st.Mode&^07777)|0600, int(st.Rdev)); err != nil {
+		return fmt.Errorf("mknod %s %s", dest, err)
+	}
+	if err := label.SetFileLabel(consolePath, mountLabel); err != nil {
+		return fmt.Errorf("set file label %s %s", dest, err)
+	}
+	if err := system.Mount(consolePath, dest, "bind", syscall.MS_BIND, ""); err != nil {
+		return fmt.Errorf("bind %s to %s %s", consolePath, dest, err)
+	}
+	return nil
+}