Documentation ¶
Index ¶
- Constants
- Variables
- func Register(name string, initFunc InitFunc) error
- type Driver
- func GetDriver(name, home string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error)
- func New(root string, name string, options []string, uidMaps, gidMaps []idtools.IDMap) (driver Driver, err error)
- func NewNaiveDiffDriver(driver ProtoDriver, uidMaps, gidMaps []idtools.IDMap) Driver
- type FsMagic
- type InitFunc
- type NaiveDiffDriver
- func (gdw *NaiveDiffDriver) ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error)
- func (gdw *NaiveDiffDriver) Changes(id, parent string) ([]archive.Change, error)
- func (gdw *NaiveDiffDriver) Diff(id, parent string) (arch archive.Archive, err error)
- func (gdw *NaiveDiffDriver) DiffSize(id, parent string) (size int64, err error)
- type ProtoDriver
Constants ¶
const ( // FsMagicAufs filesystem id for Aufs FsMagicAufs = FsMagic(0x61756673) // FsMagicBtrfs filesystem id for Btrfs FsMagicBtrfs = FsMagic(0x9123683E) // FsMagicCramfs filesystem id for Cramfs FsMagicCramfs = FsMagic(0x28cd3d45) // FsMagicExtfs filesystem id for Extfs FsMagicExtfs = FsMagic(0x0000EF53) // FsMagicF2fs filesystem id for F2fs FsMagicF2fs = FsMagic(0xF2F52010) // FsMagicGPFS filesystem id for GPFS FsMagicGPFS = FsMagic(0x47504653) // FsMagicJffs2Fs filesystem if for Jffs2Fs FsMagicJffs2Fs = FsMagic(0x000072b6) // FsMagicJfs filesystem id for Jfs FsMagicJfs = FsMagic(0x3153464a) // FsMagicNfsFs filesystem id for NfsFs FsMagicNfsFs = FsMagic(0x00006969) // FsMagicRAMFs filesystem id for RamFs FsMagicRAMFs = FsMagic(0x858458f6) // FsMagicReiserFs filesystem id for ReiserFs FsMagicReiserFs = FsMagic(0x52654973) // FsMagicSmbFs filesystem id for SmbFs FsMagicSmbFs = FsMagic(0x0000517B) // FsMagicSquashFs filesystem id for SquashFs FsMagicSquashFs = FsMagic(0x73717368) // FsMagicTmpFs filesystem id for TmpFs FsMagicTmpFs = FsMagic(0x01021994) // FsMagicVxFS filesystem id for VxFs FsMagicVxFS = FsMagic(0xa501fcf5) // FsMagicXfs filesystem id for Xfs FsMagicXfs = FsMagic(0x58465342) // FsMagicZfs filesystem id for Zfs FsMagicZfs = FsMagic(0x2fc12fc1) )
const ( // FsMagicUnsupported is a predefined constant value other than a valid filesystem id. FsMagicUnsupported = FsMagic(0x00000000) )
Variables ¶
var ( // ErrNotSupported returned when driver is not supported. ErrNotSupported = errors.New("driver not supported") // ErrPrerequisites retuned when driver does not meet prerequisites. ErrPrerequisites = errors.New("prerequisites for driver not satisfied (wrong filesystem?)") // ErrIncompatibleFS returned when file system is not supported. ErrIncompatibleFS = fmt.Errorf("backing file system is unsupported for this graph driver") )
var ( // ApplyUncompressedLayer defines the unpack method used by the graph // driver. ApplyUncompressedLayer = chrootarchive.ApplyUncompressedLayer )
var ( // FsNames maps filesystem id to name of the filesystem. FsNames = map[FsMagic]string{ FsMagicAufs: "aufs", FsMagicBtrfs: "btrfs", FsMagicCramfs: "cramfs", FsMagicExtfs: "extfs", FsMagicF2fs: "f2fs", FsMagicGPFS: "gpfs", FsMagicJffs2Fs: "jffs2", FsMagicJfs: "jfs", FsMagicNfsFs: "nfs", FsMagicRAMFs: "ramfs", FsMagicReiserFs: "reiserfs", FsMagicSmbFs: "smb", FsMagicSquashFs: "squashfs", FsMagicTmpFs: "tmpfs", FsMagicUnsupported: "unsupported", FsMagicVxFS: "vxfs", FsMagicXfs: "xfs", FsMagicZfs: "zfs", } )
Functions ¶
Types ¶
type Driver ¶
type Driver interface { ProtoDriver // Diff produces an archive of the changes between the specified // layer and its parent layer which may be "". Diff(id, parent string) (archive.Archive, error) // Changes produces a list of changes between the specified layer // and its parent layer. If parent is "", then all changes will be ADD changes. Changes(id, parent string) ([]archive.Change, error) // ApplyDiff extracts the changeset from the given diff into the // layer with the specified id and parent, returning the size of the // new layer in bytes. // The archive.Reader must be an uncompressed stream. ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error) // DiffSize calculates the changes between the specified id // and its parent and returns the size in bytes of the changes // relative to its base filesystem directory. DiffSize(id, parent string) (size int64, err error) }
Driver is the interface for layered/snapshot file system drivers.
func GetDriver ¶
func GetDriver(name, home string, options []string, uidMaps, gidMaps []idtools.IDMap) (Driver, error)
GetDriver initializes and returns the registered driver
func New ¶
func New(root string, name string, options []string, uidMaps, gidMaps []idtools.IDMap) (driver Driver, err error)
New creates the driver and initializes it at the specified root.
func NewNaiveDiffDriver ¶
func NewNaiveDiffDriver(driver ProtoDriver, uidMaps, gidMaps []idtools.IDMap) Driver
NewNaiveDiffDriver returns a fully functional driver that wraps the given ProtoDriver and adds the capability of the following methods which it may or may not support on its own:
Diff(id, parent string) (archive.Archive, error) Changes(id, parent string) ([]archive.Change, error) ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error) DiffSize(id, parent string) (size int64, err error)
type FsMagic ¶
type FsMagic uint32
FsMagic unsigned id of the filesystem in use.
func GetFSMagic ¶
GetFSMagic returns the filesystem id given the path.
type NaiveDiffDriver ¶
type NaiveDiffDriver struct { ProtoDriver // contains filtered or unexported fields }
NaiveDiffDriver takes a ProtoDriver and adds the capability of the Diffing methods which it may or may not support on its own. See the comment on the exported NewNaiveDiffDriver function below. Notably, the AUFS driver doesn't need to be wrapped like this.
func (*NaiveDiffDriver) ApplyDiff ¶
func (gdw *NaiveDiffDriver) ApplyDiff(id, parent string, diff archive.Reader) (size int64, err error)
ApplyDiff extracts the changeset from the given diff into the layer with the specified id and parent, returning the size of the new layer in bytes.
func (*NaiveDiffDriver) Changes ¶
func (gdw *NaiveDiffDriver) Changes(id, parent string) ([]archive.Change, error)
Changes produces a list of changes between the specified layer and its parent layer. If parent is "", then all changes will be ADD changes.
type ProtoDriver ¶
type ProtoDriver interface { // String returns a string representation of this driver. String() string // Create creates a new, empty, filesystem layer with the // specified id and parent and mountLabel. Parent and mountLabel may be "". Create(id, parent, mountLabel string) error // Remove attempts to remove the filesystem layer with this id. Remove(id string) error // Get returns the mountpoint for the layered filesystem referred // to by this id. You can optionally specify a mountLabel or "". // Returns the absolute path to the mounted layered filesystem. Get(id, mountLabel string) (dir string, err error) // Put releases the system resources for the specified id, // e.g, unmounting layered filesystem. Put(id string) error // Exists returns whether a filesystem layer with the specified // ID exists on this driver. Exists(id string) bool // Status returns a set of key-value pairs which give low // level diagnostic status about this driver. Status() [][2]string // Returns a set of key-value pairs which give low level information // about the image/container driver is managing. GetMetadata(id string) (map[string]string, error) // Cleanup performs necessary tasks to release resources // held by the driver, e.g., unmounting all layered filesystems // known to this driver. Cleanup() error }
ProtoDriver defines the basic capabilities of a driver. This interface exists solely to be a minimum set of methods for client code which choose not to implement the entire Driver interface and use the NaiveDiffDriver wrapper constructor.
Use of ProtoDriver directly by client code is not recommended.