container/container_unix.go
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 // +build !windows
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 package container // import "github.com/docker/docker/container"
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 import (
 	"io/ioutil"
 	"os"
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 	"path/filepath"
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 	"syscall"
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 	"github.com/containerd/continuity/fs"
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 	"github.com/docker/docker/api/types"
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 	containertypes "github.com/docker/docker/api/types/container"
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 	mounttypes "github.com/docker/docker/api/types/mount"
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 	swarmtypes "github.com/docker/docker/api/types/swarm"
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 	"github.com/docker/docker/pkg/mount"
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 	"github.com/docker/docker/pkg/stringid"
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 	"github.com/docker/docker/volume"
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 	volumemounts "github.com/docker/docker/volume/mounts"
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 	"github.com/opencontainers/selinux/go-selinux/label"
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 	"github.com/pkg/errors"
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 	"github.com/sirupsen/logrus"
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 )
 
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 const (
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 	// DefaultStopTimeout sets the default time, in seconds, to wait
 	// for the graceful container stop before forcefully terminating it.
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 	DefaultStopTimeout = 10
 
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 	containerSecretMountPath = "/run/secrets"
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 )
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 // TrySetNetworkMount attempts to set the network mounts given a provided destination and
 // the path to use for it; return true if the given destination was a network mount file
 func (container *Container) TrySetNetworkMount(destination string, path string) bool {
 	if destination == "/etc/resolv.conf" {
 		container.ResolvConfPath = path
 		return true
 	}
 	if destination == "/etc/hostname" {
 		container.HostnamePath = path
 		return true
 	}
 	if destination == "/etc/hosts" {
 		container.HostsPath = path
 		return true
 	}
 
 	return false
 }
 
 // BuildHostnameFile writes the container's hostname file.
 func (container *Container) BuildHostnameFile() error {
 	hostnamePath, err := container.GetRootResourcePath("hostname")
 	if err != nil {
 		return err
 	}
 	container.HostnamePath = hostnamePath
 	return ioutil.WriteFile(container.HostnamePath, []byte(container.Config.Hostname+"\n"), 0644)
 }
 
 // NetworkMounts returns the list of network mounts.
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 func (container *Container) NetworkMounts() []Mount {
 	var mounts []Mount
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 	shared := container.HostConfig.NetworkMode.IsContainer()
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 	parser := volumemounts.NewParser(container.OS)
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 	if container.ResolvConfPath != "" {
 		if _, err := os.Stat(container.ResolvConfPath); err != nil {
 			logrus.Warnf("ResolvConfPath set to %q, but can't stat this filename (err = %v); skipping", container.ResolvConfPath, err)
 		} else {
 			writable := !container.HostConfig.ReadonlyRootfs
 			if m, exists := container.MountPoints["/etc/resolv.conf"]; exists {
 				writable = m.RW
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 			} else {
 				label.Relabel(container.ResolvConfPath, container.MountLabel, shared)
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 			}
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 			mounts = append(mounts, Mount{
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 				Source:      container.ResolvConfPath,
 				Destination: "/etc/resolv.conf",
 				Writable:    writable,
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 				Propagation: string(parser.DefaultPropagationMode()),
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 			})
 		}
 	}
 	if container.HostnamePath != "" {
 		if _, err := os.Stat(container.HostnamePath); err != nil {
 			logrus.Warnf("HostnamePath set to %q, but can't stat this filename (err = %v); skipping", container.HostnamePath, err)
 		} else {
 			writable := !container.HostConfig.ReadonlyRootfs
 			if m, exists := container.MountPoints["/etc/hostname"]; exists {
 				writable = m.RW
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 			} else {
 				label.Relabel(container.HostnamePath, container.MountLabel, shared)
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 			}
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 			mounts = append(mounts, Mount{
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 				Source:      container.HostnamePath,
 				Destination: "/etc/hostname",
 				Writable:    writable,
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 				Propagation: string(parser.DefaultPropagationMode()),
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 			})
 		}
 	}
 	if container.HostsPath != "" {
 		if _, err := os.Stat(container.HostsPath); err != nil {
 			logrus.Warnf("HostsPath set to %q, but can't stat this filename (err = %v); skipping", container.HostsPath, err)
 		} else {
 			writable := !container.HostConfig.ReadonlyRootfs
 			if m, exists := container.MountPoints["/etc/hosts"]; exists {
 				writable = m.RW
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 			} else {
 				label.Relabel(container.HostsPath, container.MountLabel, shared)
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 			}
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 			mounts = append(mounts, Mount{
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 				Source:      container.HostsPath,
 				Destination: "/etc/hosts",
 				Writable:    writable,
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 				Propagation: string(parser.DefaultPropagationMode()),
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 			})
 		}
 	}
 	return mounts
 }
 
 // CopyImagePathContent copies files in destination to the volume.
 func (container *Container) CopyImagePathContent(v volume.Volume, destination string) error {
7a7357da
 	rootfs, err := container.GetResourcePath(destination)
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 	if err != nil {
 		return err
 	}
 
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 	if _, err := os.Stat(rootfs); err != nil {
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 		if os.IsNotExist(err) {
 			return nil
 		}
 		return err
 	}
 
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 	id := stringid.GenerateRandomID()
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 	path, err := v.Mount(id)
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 	if err != nil {
 		return err
 	}
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 	defer func() {
 		if err := v.Unmount(id); err != nil {
 			logrus.Warnf("error while unmounting volume %s: %v", v.Name(), err)
 		}
 	}()
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 	if err := label.Relabel(path, container.MountLabel, true); err != nil && !errors.Is(err, syscall.ENOTSUP) {
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 		return err
 	}
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 	return copyExistingContents(rootfs, path)
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 }
 
 // ShmResourcePath returns path to shm
 func (container *Container) ShmResourcePath() (string, error) {
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 	return container.MountsResourcePath("shm")
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 }
 
 // HasMountFor checks if path is a mountpoint
 func (container *Container) HasMountFor(path string) bool {
 	_, exists := container.MountPoints[path]
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 	if exists {
 		return true
 	}
 
 	// Also search among the tmpfs mounts
 	for dest := range container.HostConfig.Tmpfs {
 		if dest == path {
 			return true
 		}
 	}
 
 	return false
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 }
 
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 // UnmountIpcMount unmounts shm if it was mounted
 func (container *Container) UnmountIpcMount() error {
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 	if container.HasMountFor("/dev/shm") {
 		return nil
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 	}
 
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 	// container.ShmPath should not be used here as it may point
 	// to the host's or other container's /dev/shm
 	shmPath, err := container.ShmResourcePath()
 	if err != nil {
 		return err
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 	}
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 	if shmPath == "" {
 		return nil
 	}
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 	if err = mount.Unmount(shmPath); err != nil && !os.IsNotExist(errors.Cause(err)) {
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 		return err
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 	}
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 	return nil
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 }
 
 // IpcMounts returns the list of IPC mounts
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 func (container *Container) IpcMounts() []Mount {
 	var mounts []Mount
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 	parser := volumemounts.NewParser(container.OS)
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 	if container.HasMountFor("/dev/shm") {
 		return mounts
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 	}
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 	if container.ShmPath == "" {
 		return mounts
 	}
 
 	label.SetFileLabel(container.ShmPath, container.MountLabel)
 	mounts = append(mounts, Mount{
 		Source:      container.ShmPath,
 		Destination: "/dev/shm",
 		Writable:    true,
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 		Propagation: string(parser.DefaultPropagationMode()),
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 	})
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 	return mounts
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 }
 
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 // SecretMounts returns the mounts for the secret path.
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 func (container *Container) SecretMounts() ([]Mount, error) {
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 	var mounts []Mount
 	for _, r := range container.SecretReferences {
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 		if r.File == nil {
 			continue
 		}
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 		src, err := container.SecretFilePath(*r)
 		if err != nil {
 			return nil, err
 		}
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 		mounts = append(mounts, Mount{
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 			Source:      src,
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 			Destination: getSecretTargetPath(r),
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 			Writable:    false,
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 		})
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 	}
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 	for _, r := range container.ConfigReferences {
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 		fPath, err := container.ConfigFilePath(*r)
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 		if err != nil {
 			return nil, err
 		}
 		mounts = append(mounts, Mount{
 			Source:      fPath,
 			Destination: r.File.Name,
 			Writable:    false,
 		})
 	}
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 	return mounts, nil
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 }
 
 // UnmountSecrets unmounts the local tmpfs for secrets
 func (container *Container) UnmountSecrets() error {
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 	p, err := container.SecretMountPath()
 	if err != nil {
 		return err
 	}
 	if _, err := os.Stat(p); err != nil {
643ae8b4
 		if os.IsNotExist(err) {
 			return nil
 		}
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 		return err
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 	}
 
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 	return mount.RecursiveUnmount(p)
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 }
 
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 type conflictingUpdateOptions string
 
 func (e conflictingUpdateOptions) Error() string {
 	return string(e)
 }
 
 func (e conflictingUpdateOptions) Conflict() {}
 
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 // UpdateContainer updates configuration of a container. Callers must hold a Lock on the Container.
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 func (container *Container) UpdateContainer(hostConfig *containertypes.HostConfig) error {
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 	// update resources of container
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 	resources := hostConfig.Resources
 	cResources := &container.HostConfig.Resources
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 	// validate NanoCPUs, CPUPeriod, and CPUQuota
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 	// Because NanoCPU effectively updates CPUPeriod/CPUQuota,
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 	// once NanoCPU is already set, updating CPUPeriod/CPUQuota will be blocked, and vice versa.
 	// In the following we make sure the intended update (resources) does not conflict with the existing (cResource).
 	if resources.NanoCPUs > 0 && cResources.CPUPeriod > 0 {
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 		return conflictingUpdateOptions("Conflicting options: Nano CPUs cannot be updated as CPU Period has already been set")
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 	}
 	if resources.NanoCPUs > 0 && cResources.CPUQuota > 0 {
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 		return conflictingUpdateOptions("Conflicting options: Nano CPUs cannot be updated as CPU Quota has already been set")
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 	}
 	if resources.CPUPeriod > 0 && cResources.NanoCPUs > 0 {
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 		return conflictingUpdateOptions("Conflicting options: CPU Period cannot be updated as NanoCPUs has already been set")
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 	}
 	if resources.CPUQuota > 0 && cResources.NanoCPUs > 0 {
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 		return conflictingUpdateOptions("Conflicting options: CPU Quota cannot be updated as NanoCPUs has already been set")
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 	}
 
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 	if resources.BlkioWeight != 0 {
 		cResources.BlkioWeight = resources.BlkioWeight
 	}
 	if resources.CPUShares != 0 {
 		cResources.CPUShares = resources.CPUShares
 	}
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 	if resources.NanoCPUs != 0 {
 		cResources.NanoCPUs = resources.NanoCPUs
 	}
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 	if resources.CPUPeriod != 0 {
 		cResources.CPUPeriod = resources.CPUPeriod
 	}
 	if resources.CPUQuota != 0 {
 		cResources.CPUQuota = resources.CPUQuota
 	}
 	if resources.CpusetCpus != "" {
 		cResources.CpusetCpus = resources.CpusetCpus
 	}
 	if resources.CpusetMems != "" {
 		cResources.CpusetMems = resources.CpusetMems
 	}
 	if resources.Memory != 0 {
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 		// if memory limit smaller than already set memoryswap limit and doesn't
 		// update the memoryswap limit, then error out.
 		if resources.Memory > cResources.MemorySwap && resources.MemorySwap == 0 {
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 			return conflictingUpdateOptions("Memory limit should be smaller than already set memoryswap limit, update the memoryswap at the same time")
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 		}
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 		cResources.Memory = resources.Memory
 	}
 	if resources.MemorySwap != 0 {
 		cResources.MemorySwap = resources.MemorySwap
 	}
 	if resources.MemoryReservation != 0 {
 		cResources.MemoryReservation = resources.MemoryReservation
 	}
 	if resources.KernelMemory != 0 {
 		cResources.KernelMemory = resources.KernelMemory
 	}
dca82b9e
 	if resources.CPURealtimePeriod != 0 {
 		cResources.CPURealtimePeriod = resources.CPURealtimePeriod
 	}
 	if resources.CPURealtimeRuntime != 0 {
 		cResources.CPURealtimeRuntime = resources.CPURealtimeRuntime
 	}
74eb258f
 	if resources.PidsLimit != nil {
 		cResources.PidsLimit = resources.PidsLimit
 	}
ff3ea4c9
 
 	// update HostConfig of container
 	if hostConfig.RestartPolicy.Name != "" {
4754c64a
 		if container.HostConfig.AutoRemove && !hostConfig.RestartPolicy.IsNone() {
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 			return conflictingUpdateOptions("Restart policy cannot be updated because AutoRemove is enabled for the container")
4754c64a
 		}
ff3ea4c9
 		container.HostConfig.RestartPolicy = hostConfig.RestartPolicy
 	}
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 	return nil
 }
 
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 // DetachAndUnmount uses a detached mount on all mount destinations, then
 // unmounts each volume normally.
 // This is used from daemon/archive for `docker cp`
 func (container *Container) DetachAndUnmount(volumeEventLog func(name, action string, attributes map[string]string)) error {
 	networkMounts := container.NetworkMounts()
 	mountPaths := make([]string, 0, len(container.MountPoints)+len(networkMounts))
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 	for _, mntPoint := range container.MountPoints {
 		dest, err := container.GetResourcePath(mntPoint.Destination)
 		if err != nil {
9a2d0bc3
 			logrus.Warnf("Failed to get volume destination path for container '%s' at '%s' while lazily unmounting: %v", container.ID, mntPoint.Destination, err)
 			continue
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 		}
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 		mountPaths = append(mountPaths, dest)
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 	}
 
9a2d0bc3
 	for _, m := range networkMounts {
 		dest, err := container.GetResourcePath(m.Destination)
 		if err != nil {
 			logrus.Warnf("Failed to get volume destination path for container '%s' at '%s' while lazily unmounting: %v", container.ID, m.Destination, err)
 			continue
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 		}
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 		mountPaths = append(mountPaths, dest)
 	}
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9a2d0bc3
 	for _, mountPath := range mountPaths {
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 		if err := mount.Unmount(mountPath); err != nil {
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 			logrus.WithError(err).WithField("container", container.ID).
 				Warn("Unable to unmount")
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 		}
 	}
9a2d0bc3
 	return container.UnmountVolumes(volumeEventLog)
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 }
 
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 // ignoreUnsupportedXAttrs ignores errors when extended attributes
 // are not supported
 func ignoreUnsupportedXAttrs() fs.CopyDirOpt {
 	xeh := func(dst, src, xattrKey string, err error) error {
 		if errors.Cause(err) != syscall.ENOTSUP {
 			return err
 		}
 		return nil
 	}
 	return fs.WithXAttrErrorHandler(xeh)
 }
 
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 // copyExistingContents copies from the source to the destination and
 // ensures the ownership is appropriately set.
 func copyExistingContents(source, destination string) error {
b3aab5e3
 	dstList, err := ioutil.ReadDir(destination)
6bb0d181
 	if err != nil {
 		return err
 	}
b3aab5e3
 	if len(dstList) != 0 {
 		// destination is not empty, do not copy
 		return nil
f05a0237
 	}
d0192ae1
 	return fs.CopyDir(destination, source, ignoreUnsupportedXAttrs())
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 }
 
 // TmpfsMounts returns the list of tmpfs mounts
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 func (container *Container) TmpfsMounts() ([]Mount, error) {
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 	parser := volumemounts.NewParser(container.OS)
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 	var mounts []Mount
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 	for dest, data := range container.HostConfig.Tmpfs {
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 		mounts = append(mounts, Mount{
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 			Source:      "tmpfs",
 			Destination: dest,
 			Data:        data,
 		})
 	}
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 	for dest, mnt := range container.MountPoints {
 		if mnt.Type == mounttypes.TypeTmpfs {
e89b6e8c
 			data, err := parser.ConvertTmpfsOptions(mnt.Spec.TmpfsOptions, mnt.Spec.ReadOnly)
18768fdc
 			if err != nil {
 				return nil, err
 			}
 			mounts = append(mounts, Mount{
 				Source:      "tmpfs",
 				Destination: dest,
 				Data:        data,
 			})
 		}
 	}
 	return mounts, nil
6bb0d181
 }
67912303
 
cfc404a3
 // GetMountPoints gives a platform specific transformation to types.MountPoint. Callers must hold a Container lock.
 func (container *Container) GetMountPoints() []types.MountPoint {
 	mountPoints := make([]types.MountPoint, 0, len(container.MountPoints))
 	for _, m := range container.MountPoints {
 		mountPoints = append(mountPoints, types.MountPoint{
 			Type:        m.Type,
 			Name:        m.Name,
 			Source:      m.Path(),
 			Destination: m.Destination,
 			Driver:      m.Driver,
 			Mode:        m.Mode,
 			RW:          m.RW,
 			Propagation: m.Propagation,
 		})
 	}
 	return mountPoints
 }
c0217180
 
 // ConfigFilePath returns the path to the on-disk location of a config.
 // On unix, configs are always considered secret
 func (container *Container) ConfigFilePath(configRef swarmtypes.ConfigReference) (string, error) {
 	mounts, err := container.SecretMountPath()
 	if err != nil {
 		return "", err
 	}
 	return filepath.Join(mounts, configRef.ConfigID), nil
 }