package daemon

 
 import (

 	"errors"

 	"fmt"

 	"os"
 	"path/filepath"
 	"strings"

 	"github.com/docker/docker/container"

 	"github.com/docker/docker/volume"

 	"github.com/docker/engine-api/types"
 	containertypes "github.com/docker/engine-api/types/container"

 )
 

 var (
 	// ErrVolumeReadonly is used to signal an error when trying to copy data into
 	// a volume mount that is not writable.
 	ErrVolumeReadonly = errors.New("mounted volume is marked read-only")
 )

 type mounts []container.Mount

 // volumeToAPIType converts a volume.Volume to the type used by the remote API
 func volumeToAPIType(v volume.Volume) *types.Volume {

 	tv := &types.Volume{

 		Name:   v.Name(),
 		Driver: v.DriverName(),

 	}

 	if v, ok := v.(volume.LabeledVolume); ok {

 		tv.Labels = v.Labels()
 	}

 
 	if v, ok := v.(volume.ScopedVolume); ok {
 		tv.Scope = v.Scope()
 	}

 	return tv

 }

 // Len returns the number of mounts. Used in sorting.
 func (m mounts) Len() int {
 	return len(m)
 }

 // Less returns true if the number of parts (a/b/c would be 3 parts) in the
 // mount indexed by parameter 1 is less than that of the mount indexed by
 // parameter 2. Used in sorting.
 func (m mounts) Less(i, j int) bool {
 	return m.parts(i) < m.parts(j)

 }
 

 // Swap swaps two items in an array of mounts. Used in sorting
 func (m mounts) Swap(i, j int) {
 	m[i], m[j] = m[j], m[i]
 }

 // parts returns the number of parts in the destination of a mount. Used in sorting.
 func (m mounts) parts(i int) int {
 	return strings.Count(filepath.Clean(m[i].Destination), string(os.PathSeparator))

 }
 

 // registerMountPoints initializes the container mount points with the configured volumes and bind mounts.
 // It follows the next sequence to decide what to mount in each final destination:
 //
 // 1. Select the previously configured mount points for the containers, if any.
 // 2. Select the volumes mounted from another containers. Overrides previously configured mount point destination.
 // 3. Select the bind mounts set by the client. Overrides previously configured mount point destinations.

 // 4. Cleanup old volumes that are about to be reassigned.

 func (daemon *Daemon) registerMountPoints(container *container.Container, hostConfig *containertypes.HostConfig) (retErr error) {

 	binds := map[string]bool{}
 	mountPoints := map[string]*volume.MountPoint{}

 	defer func() {
 		// clean up the container mountpoints once return with error
 		if retErr != nil {
 			for _, m := range mountPoints {
 				if m.Volume == nil {
 					continue
 				}
 				daemon.volumes.Dereference(m.Volume, container.ID)
 			}
 		}
 	}()

 
 	// 1. Read already configured mount points.
 	for name, point := range container.MountPoints {
 		mountPoints[name] = point

 	}
 

 	// 2. Read volumes from other containers.
 	for _, v := range hostConfig.VolumesFrom {
 		containerID, mode, err := volume.ParseVolumesFrom(v)
 		if err != nil {
 			return err
 		}

 		c, err := daemon.GetContainer(containerID)

 		if err != nil {
 			return err
 		}
 
 		for _, m := range c.MountPoints {
 			cp := &volume.MountPoint{
 				Name:        m.Name,
 				Source:      m.Source,
 				RW:          m.RW && volume.ReadWrite(mode),
 				Driver:      m.Driver,
 				Destination: m.Destination,

 				Propagation: m.Propagation,

 				Named:       m.Named,

 			}
 
 			if len(cp.Source) == 0 {

 				v, err := daemon.volumes.GetWithRef(cp.Name, cp.Driver, container.ID)

 				if err != nil {
 					return err
 				}
 				cp.Volume = v
 			}
 
 			mountPoints[cp.Destination] = cp
 		}

 	}

 
 	// 3. Read bind mounts
 	for _, b := range hostConfig.Binds {
 		// #10618
 		bind, err := volume.ParseMountSpec(b, hostConfig.VolumeDriver)

 		if err != nil {

 			return err

 		}

 		_, tmpfsExists := hostConfig.Tmpfs[bind.Destination]
 		if binds[bind.Destination] || tmpfsExists {

 			return fmt.Errorf("Duplicate mount point '%s'", bind.Destination)

 		}
 

 		if len(bind.Name) > 0 {

 			// create the volume

 			v, err := daemon.volumes.CreateWithRef(bind.Name, bind.Driver, container.ID, nil, nil)

 			if err != nil {

 				return err
 			}

 			bind.Volume = v
 			bind.Source = v.Path()
 			// bind.Name is an already existing volume, we need to use that here
 			bind.Driver = v.DriverName()

 			bind.Named = true

 			if bind.Driver == "local" {
 				bind = setBindModeIfNull(bind)
 			}

 		}

 		binds[bind.Destination] = true
 		mountPoints[bind.Destination] = bind

 	}

 	container.Lock()

 	// 4. Cleanup old volumes that are about to be reassigned.

 	for _, m := range mountPoints {
 		if m.BackwardsCompatible() {
 			if mp, exists := container.MountPoints[m.Destination]; exists && mp.Volume != nil {

 				daemon.volumes.Dereference(mp.Volume, container.ID)

 			}
 		}
 	}

 	container.MountPoints = mountPoints
 
 	container.Unlock()
 
 	return nil

 }

 
 // lazyInitializeVolume initializes a mountpoint's volume if needed.
 // This happens after a daemon restart.
 func (daemon *Daemon) lazyInitializeVolume(containerID string, m *volume.MountPoint) error {
 	if len(m.Driver) > 0 && m.Volume == nil {
 		v, err := daemon.volumes.GetWithRef(m.Name, m.Driver, containerID)
 		if err != nil {
 			return err
 		}
 		m.Volume = v
 	}
 	return nil
 }