moby/daemon/daemon.go
Eng Zer Jun a916414b0b refactor: move from io/ioutil to io and os package
The io/ioutil package has been deprecated in Go 1.16. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.

Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
(cherry picked from commit c55a4ac779)
Signed-off-by: Cory Snider <csnider@mirantis.com>
2023-02-24 16:11:55 -05:00

1593 lines
51 KiB
Go

// Package daemon exposes the functions that occur on the host server
// that the Docker daemon is running.
//
// In implementing the various functions of the daemon, there is often
// a method-specific struct for configuring the runtime behavior.
package daemon // import "github.com/docker/docker/daemon"
import (
"context"
"fmt"
"net"
"net/url"
"os"
"path"
"path/filepath"
"runtime"
"strings"
"sync"
"time"
"github.com/docker/docker/pkg/fileutils"
"go.etcd.io/bbolt"
"google.golang.org/grpc"
"google.golang.org/grpc/backoff"
"github.com/containerd/containerd"
"github.com/containerd/containerd/defaults"
"github.com/containerd/containerd/pkg/dialer"
"github.com/containerd/containerd/remotes/docker"
"github.com/containerd/containerd/sys"
"github.com/docker/docker/api/types"
containertypes "github.com/docker/docker/api/types/container"
"github.com/docker/docker/api/types/swarm"
"github.com/docker/docker/builder"
"github.com/docker/docker/container"
"github.com/docker/docker/daemon/config"
"github.com/docker/docker/daemon/discovery"
"github.com/docker/docker/daemon/events"
"github.com/docker/docker/daemon/exec"
"github.com/docker/docker/daemon/images"
"github.com/docker/docker/daemon/logger"
"github.com/docker/docker/daemon/network"
"github.com/docker/docker/errdefs"
bkconfig "github.com/moby/buildkit/cmd/buildkitd/config"
"github.com/moby/buildkit/util/resolver"
"github.com/sirupsen/logrus"
// register graph drivers
_ "github.com/docker/docker/daemon/graphdriver/register"
"github.com/docker/docker/daemon/stats"
dmetadata "github.com/docker/docker/distribution/metadata"
"github.com/docker/docker/dockerversion"
"github.com/docker/docker/image"
"github.com/docker/docker/layer"
"github.com/docker/docker/libcontainerd"
libcontainerdtypes "github.com/docker/docker/libcontainerd/types"
"github.com/docker/docker/pkg/idtools"
"github.com/docker/docker/pkg/plugingetter"
"github.com/docker/docker/pkg/system"
"github.com/docker/docker/pkg/truncindex"
"github.com/docker/docker/plugin"
pluginexec "github.com/docker/docker/plugin/executor/containerd"
refstore "github.com/docker/docker/reference"
"github.com/docker/docker/registry"
"github.com/docker/docker/runconfig"
volumesservice "github.com/docker/docker/volume/service"
"github.com/docker/libnetwork"
"github.com/docker/libnetwork/cluster"
nwconfig "github.com/docker/libnetwork/config"
"github.com/moby/locker"
"github.com/pkg/errors"
"golang.org/x/sync/semaphore"
)
// ContainersNamespace is the name of the namespace used for users containers
const (
ContainersNamespace = "moby"
)
var (
errSystemNotSupported = errors.New("the Docker daemon is not supported on this platform")
)
// Daemon holds information about the Docker daemon.
type Daemon struct {
ID string
repository string
containers container.Store
containersReplica container.ViewDB
execCommands *exec.Store
imageService *images.ImageService
idIndex *truncindex.TruncIndex
configStore *config.Config
statsCollector *stats.Collector
defaultLogConfig containertypes.LogConfig
RegistryService registry.Service
EventsService *events.Events
netController libnetwork.NetworkController
volumes *volumesservice.VolumesService
discoveryWatcher discovery.Reloader
root string
seccompEnabled bool
apparmorEnabled bool
shutdown bool
idMapping *idtools.IdentityMapping
// TODO: move graphDrivers field to an InfoService
graphDrivers map[string]string // By operating system
PluginStore *plugin.Store // todo: remove
pluginManager *plugin.Manager
linkIndex *linkIndex
containerdCli *containerd.Client
containerd libcontainerdtypes.Client
defaultIsolation containertypes.Isolation // Default isolation mode on Windows
clusterProvider cluster.Provider
cluster Cluster
genericResources []swarm.GenericResource
metricsPluginListener net.Listener
machineMemory uint64
seccompProfile []byte
seccompProfilePath string
diskUsageRunning int32
pruneRunning int32
hosts map[string]bool // hosts stores the addresses the daemon is listening on
startupDone chan struct{}
attachmentStore network.AttachmentStore
attachableNetworkLock *locker.Locker
// This is used for Windows which doesn't currently support running on containerd
// It stores metadata for the content store (used for manifest caching)
// This needs to be closed on daemon exit
mdDB *bbolt.DB
}
// StoreHosts stores the addresses the daemon is listening on
func (daemon *Daemon) StoreHosts(hosts []string) {
if daemon.hosts == nil {
daemon.hosts = make(map[string]bool)
}
for _, h := range hosts {
daemon.hosts[h] = true
}
}
// HasExperimental returns whether the experimental features of the daemon are enabled or not
func (daemon *Daemon) HasExperimental() bool {
return daemon.configStore != nil && daemon.configStore.Experimental
}
// Features returns the features map from configStore
func (daemon *Daemon) Features() *map[string]bool {
return &daemon.configStore.Features
}
// RegistryHosts returns registry configuration in containerd resolvers format
func (daemon *Daemon) RegistryHosts() docker.RegistryHosts {
var (
registryKey = "docker.io"
mirrors = make([]string, len(daemon.configStore.Mirrors))
m = map[string]bkconfig.RegistryConfig{}
)
// must trim "https://" or "http://" prefix
for i, v := range daemon.configStore.Mirrors {
if uri, err := url.Parse(v); err == nil {
v = uri.Host
}
mirrors[i] = v
}
// set mirrors for default registry
m[registryKey] = bkconfig.RegistryConfig{Mirrors: mirrors}
for _, v := range daemon.configStore.InsecureRegistries {
u, err := url.Parse(v)
c := bkconfig.RegistryConfig{}
if err == nil {
v = u.Host
t := true
if u.Scheme == "http" {
c.PlainHTTP = &t
} else {
c.Insecure = &t
}
}
m[v] = c
}
for k, v := range m {
if d, err := registry.HostCertsDir(k); err == nil {
v.TLSConfigDir = []string{d}
m[k] = v
}
}
certsDir := registry.CertsDir()
if fis, err := os.ReadDir(certsDir); err == nil {
for _, fi := range fis {
if _, ok := m[fi.Name()]; !ok {
m[fi.Name()] = bkconfig.RegistryConfig{
TLSConfigDir: []string{filepath.Join(certsDir, fi.Name())},
}
}
}
}
return resolver.NewRegistryConfig(m)
}
func (daemon *Daemon) restore() error {
var mapLock sync.Mutex
containers := make(map[string]*container.Container)
logrus.Info("Loading containers: start.")
dir, err := os.ReadDir(daemon.repository)
if err != nil {
return err
}
// parallelLimit is the maximum number of parallel startup jobs that we
// allow (this is the limited used for all startup semaphores). The multipler
// (128) was chosen after some fairly significant benchmarking -- don't change
// it unless you've tested it significantly (this value is adjusted if
// RLIMIT_NOFILE is small to avoid EMFILE).
parallelLimit := adjustParallelLimit(len(dir), 128*runtime.NumCPU())
// Re-used for all parallel startup jobs.
var group sync.WaitGroup
sem := semaphore.NewWeighted(int64(parallelLimit))
for _, v := range dir {
group.Add(1)
go func(id string) {
defer group.Done()
_ = sem.Acquire(context.Background(), 1)
defer sem.Release(1)
log := logrus.WithField("container", id)
c, err := daemon.load(id)
if err != nil {
log.WithError(err).Error("failed to load container")
return
}
if !system.IsOSSupported(c.OS) {
log.Errorf("failed to load container: %s (%q)", system.ErrNotSupportedOperatingSystem, c.OS)
return
}
// Ignore the container if it does not support the current driver being used by the graph
currentDriverForContainerOS := daemon.graphDrivers[c.OS]
if (c.Driver == "" && currentDriverForContainerOS == "aufs") || c.Driver == currentDriverForContainerOS {
rwlayer, err := daemon.imageService.GetLayerByID(c.ID, c.OS)
if err != nil {
log.WithError(err).Error("failed to load container mount")
return
}
c.RWLayer = rwlayer
log.WithFields(logrus.Fields{
"running": c.IsRunning(),
"paused": c.IsPaused(),
}).Debug("loaded container")
mapLock.Lock()
containers[c.ID] = c
mapLock.Unlock()
} else {
log.Debugf("cannot load container because it was created with another storage driver")
}
}(v.Name())
}
group.Wait()
removeContainers := make(map[string]*container.Container)
restartContainers := make(map[*container.Container]chan struct{})
activeSandboxes := make(map[string]interface{})
for _, c := range containers {
group.Add(1)
go func(c *container.Container) {
defer group.Done()
_ = sem.Acquire(context.Background(), 1)
defer sem.Release(1)
log := logrus.WithField("container", c.ID)
if err := daemon.registerName(c); err != nil {
log.WithError(err).Errorf("failed to register container name: %s", c.Name)
mapLock.Lock()
delete(containers, c.ID)
mapLock.Unlock()
return
}
if err := daemon.Register(c); err != nil {
log.WithError(err).Error("failed to register container")
mapLock.Lock()
delete(containers, c.ID)
mapLock.Unlock()
return
}
// The LogConfig.Type is empty if the container was created before docker 1.12 with default log driver.
// We should rewrite it to use the daemon defaults.
// Fixes https://github.com/docker/docker/issues/22536
if c.HostConfig.LogConfig.Type == "" {
if err := daemon.mergeAndVerifyLogConfig(&c.HostConfig.LogConfig); err != nil {
log.WithError(err).Error("failed to verify log config for container")
}
}
}(c)
}
group.Wait()
for _, c := range containers {
group.Add(1)
go func(c *container.Container) {
defer group.Done()
_ = sem.Acquire(context.Background(), 1)
defer sem.Release(1)
log := logrus.WithField("container", c.ID)
daemon.backportMountSpec(c)
if err := daemon.checkpointAndSave(c); err != nil {
log.WithError(err).Error("error saving backported mountspec to disk")
}
daemon.setStateCounter(c)
logger := func(c *container.Container) *logrus.Entry {
return log.WithFields(logrus.Fields{
"running": c.IsRunning(),
"paused": c.IsPaused(),
"restarting": c.IsRestarting(),
})
}
logger(c).Debug("restoring container")
var (
err error
alive bool
ec uint32
exitedAt time.Time
process libcontainerdtypes.Process
)
alive, _, process, err = daemon.containerd.Restore(context.Background(), c.ID, c.InitializeStdio)
if err != nil && !errdefs.IsNotFound(err) {
logger(c).WithError(err).Error("failed to restore container with containerd")
return
}
logger(c).Debugf("alive: %v", alive)
if !alive {
// If process is not nil, cleanup dead container from containerd.
// If process is nil then the above `containerd.Restore` returned an errdefs.NotFoundError,
// and docker's view of the container state will be updated accorrdingly via SetStopped further down.
if process != nil {
logger(c).Debug("cleaning up dead container process")
ec, exitedAt, err = process.Delete(context.Background())
if err != nil && !errdefs.IsNotFound(err) {
logger(c).WithError(err).Error("failed to delete container from containerd")
return
}
}
} else if !daemon.configStore.LiveRestoreEnabled {
logger(c).Debug("shutting down container considered alive by containerd")
if err := daemon.shutdownContainer(c); err != nil && !errdefs.IsNotFound(err) {
log.WithError(err).Error("error shutting down container")
return
}
c.ResetRestartManager(false)
}
if c.IsRunning() || c.IsPaused() {
logger(c).Debug("syncing container on disk state with real state")
c.RestartManager().Cancel() // manually start containers because some need to wait for swarm networking
if c.IsPaused() && alive {
s, err := daemon.containerd.Status(context.Background(), c.ID)
if err != nil {
logger(c).WithError(err).Error("failed to get container status")
} else {
logger(c).WithField("state", s).Info("restored container paused")
switch s {
case containerd.Paused, containerd.Pausing:
// nothing to do
case containerd.Stopped:
alive = false
case containerd.Unknown:
log.Error("unknown status for paused container during restore")
default:
// running
c.Lock()
c.Paused = false
daemon.setStateCounter(c)
if err := c.CheckpointTo(daemon.containersReplica); err != nil {
log.WithError(err).Error("failed to update paused container state")
}
c.Unlock()
}
}
}
if !alive {
logger(c).Debug("setting stopped state")
c.Lock()
c.SetStopped(&container.ExitStatus{ExitCode: int(ec), ExitedAt: exitedAt})
daemon.Cleanup(c)
if err := c.CheckpointTo(daemon.containersReplica); err != nil {
log.WithError(err).Error("failed to update stopped container state")
}
c.Unlock()
logger(c).Debug("set stopped state")
}
// we call Mount and then Unmount to get BaseFs of the container
if err := daemon.Mount(c); err != nil {
// The mount is unlikely to fail. However, in case mount fails
// the container should be allowed to restore here. Some functionalities
// (like docker exec -u user) might be missing but container is able to be
// stopped/restarted/removed.
// See #29365 for related information.
// The error is only logged here.
logger(c).WithError(err).Warn("failed to mount container to get BaseFs path")
} else {
if err := daemon.Unmount(c); err != nil {
logger(c).WithError(err).Warn("failed to umount container to get BaseFs path")
}
}
c.ResetRestartManager(false)
if !c.HostConfig.NetworkMode.IsContainer() && c.IsRunning() {
options, err := daemon.buildSandboxOptions(c)
if err != nil {
logger(c).WithError(err).Warn("failed to build sandbox option to restore container")
}
mapLock.Lock()
activeSandboxes[c.NetworkSettings.SandboxID] = options
mapLock.Unlock()
}
}
// get list of containers we need to restart
// Do not autostart containers which
// has endpoints in a swarm scope
// network yet since the cluster is
// not initialized yet. We will start
// it after the cluster is
// initialized.
if daemon.configStore.AutoRestart && c.ShouldRestart() && !c.NetworkSettings.HasSwarmEndpoint && c.HasBeenStartedBefore {
mapLock.Lock()
restartContainers[c] = make(chan struct{})
mapLock.Unlock()
} else if c.HostConfig != nil && c.HostConfig.AutoRemove {
mapLock.Lock()
removeContainers[c.ID] = c
mapLock.Unlock()
}
c.Lock()
if c.RemovalInProgress {
// We probably crashed in the middle of a removal, reset
// the flag.
//
// We DO NOT remove the container here as we do not
// know if the user had requested for either the
// associated volumes, network links or both to also
// be removed. So we put the container in the "dead"
// state and leave further processing up to them.
c.RemovalInProgress = false
c.Dead = true
if err := c.CheckpointTo(daemon.containersReplica); err != nil {
log.WithError(err).Error("failed to update RemovalInProgress container state")
} else {
log.Debugf("reset RemovalInProgress state for container")
}
}
c.Unlock()
logger(c).Debug("done restoring container")
}(c)
}
group.Wait()
daemon.netController, err = daemon.initNetworkController(daemon.configStore, activeSandboxes)
if err != nil {
return fmt.Errorf("Error initializing network controller: %v", err)
}
// Now that all the containers are registered, register the links
for _, c := range containers {
group.Add(1)
go func(c *container.Container) {
_ = sem.Acquire(context.Background(), 1)
if err := daemon.registerLinks(c, c.HostConfig); err != nil {
logrus.WithField("container", c.ID).WithError(err).Error("failed to register link for container")
}
sem.Release(1)
group.Done()
}(c)
}
group.Wait()
for c, notifier := range restartContainers {
group.Add(1)
go func(c *container.Container, chNotify chan struct{}) {
_ = sem.Acquire(context.Background(), 1)
log := logrus.WithField("container", c.ID)
log.Debug("starting container")
// ignore errors here as this is a best effort to wait for children to be
// running before we try to start the container
children := daemon.children(c)
timeout := time.NewTimer(5 * time.Second)
defer timeout.Stop()
for _, child := range children {
if notifier, exists := restartContainers[child]; exists {
select {
case <-notifier:
case <-timeout.C:
}
}
}
if err := daemon.prepareMountPoints(c); err != nil {
log.WithError(err).Error("failed to prepare mount points for container")
}
daemon.waitForNetworks(c)
if err := daemon.containerStart(c, "", "", true); err != nil {
log.WithError(err).Error("failed to start container")
}
close(chNotify)
sem.Release(1)
group.Done()
}(c, notifier)
}
group.Wait()
for id := range removeContainers {
group.Add(1)
go func(cid string) {
_ = sem.Acquire(context.Background(), 1)
if err := daemon.ContainerRm(cid, &types.ContainerRmConfig{ForceRemove: true, RemoveVolume: true}); err != nil {
logrus.WithField("container", cid).WithError(err).Error("failed to remove container")
}
sem.Release(1)
group.Done()
}(id)
}
group.Wait()
// any containers that were started above would already have had this done,
// however we need to now prepare the mountpoints for the rest of the containers as well.
// This shouldn't cause any issue running on the containers that already had this run.
// This must be run after any containers with a restart policy so that containerized plugins
// can have a chance to be running before we try to initialize them.
for _, c := range containers {
// if the container has restart policy, do not
// prepare the mountpoints since it has been done on restarting.
// This is to speed up the daemon start when a restart container
// has a volume and the volume driver is not available.
if _, ok := restartContainers[c]; ok {
continue
} else if _, ok := removeContainers[c.ID]; ok {
// container is automatically removed, skip it.
continue
}
group.Add(1)
go func(c *container.Container) {
_ = sem.Acquire(context.Background(), 1)
if err := daemon.prepareMountPoints(c); err != nil {
logrus.WithField("container", c.ID).WithError(err).Error("failed to prepare mountpoints for container")
}
sem.Release(1)
group.Done()
}(c)
}
group.Wait()
logrus.Info("Loading containers: done.")
return nil
}
// RestartSwarmContainers restarts any autostart container which has a
// swarm endpoint.
func (daemon *Daemon) RestartSwarmContainers() {
ctx := context.Background()
// parallelLimit is the maximum number of parallel startup jobs that we
// allow (this is the limited used for all startup semaphores). The multipler
// (128) was chosen after some fairly significant benchmarking -- don't change
// it unless you've tested it significantly (this value is adjusted if
// RLIMIT_NOFILE is small to avoid EMFILE).
parallelLimit := adjustParallelLimit(len(daemon.List()), 128*runtime.NumCPU())
var group sync.WaitGroup
sem := semaphore.NewWeighted(int64(parallelLimit))
for _, c := range daemon.List() {
if !c.IsRunning() && !c.IsPaused() {
// Autostart all the containers which has a
// swarm endpoint now that the cluster is
// initialized.
if daemon.configStore.AutoRestart && c.ShouldRestart() && c.NetworkSettings.HasSwarmEndpoint && c.HasBeenStartedBefore {
group.Add(1)
go func(c *container.Container) {
if err := sem.Acquire(ctx, 1); err != nil {
// ctx is done.
group.Done()
return
}
if err := daemon.containerStart(c, "", "", true); err != nil {
logrus.WithField("container", c.ID).WithError(err).Error("failed to start swarm container")
}
sem.Release(1)
group.Done()
}(c)
}
}
}
group.Wait()
}
// waitForNetworks is used during daemon initialization when starting up containers
// It ensures that all of a container's networks are available before the daemon tries to start the container.
// In practice it just makes sure the discovery service is available for containers which use a network that require discovery.
func (daemon *Daemon) waitForNetworks(c *container.Container) {
if daemon.discoveryWatcher == nil {
return
}
// Make sure if the container has a network that requires discovery that the discovery service is available before starting
for netName := range c.NetworkSettings.Networks {
// If we get `ErrNoSuchNetwork` here, we can assume that it is due to discovery not being ready
// Most likely this is because the K/V store used for discovery is in a container and needs to be started
if _, err := daemon.netController.NetworkByName(netName); err != nil {
if _, ok := err.(libnetwork.ErrNoSuchNetwork); !ok {
continue
}
// use a longish timeout here due to some slowdowns in libnetwork if the k/v store is on anything other than --net=host
// FIXME: why is this slow???
dur := 60 * time.Second
timer := time.NewTimer(dur)
logrus.WithField("container", c.ID).Debugf("Container %s waiting for network to be ready", c.Name)
select {
case <-daemon.discoveryWatcher.ReadyCh():
case <-timer.C:
}
timer.Stop()
return
}
}
}
func (daemon *Daemon) children(c *container.Container) map[string]*container.Container {
return daemon.linkIndex.children(c)
}
// parents returns the names of the parent containers of the container
// with the given name.
func (daemon *Daemon) parents(c *container.Container) map[string]*container.Container {
return daemon.linkIndex.parents(c)
}
func (daemon *Daemon) registerLink(parent, child *container.Container, alias string) error {
fullName := path.Join(parent.Name, alias)
if err := daemon.containersReplica.ReserveName(fullName, child.ID); err != nil {
if err == container.ErrNameReserved {
logrus.Warnf("error registering link for %s, to %s, as alias %s, ignoring: %v", parent.ID, child.ID, alias, err)
return nil
}
return err
}
daemon.linkIndex.link(parent, child, fullName)
return nil
}
// DaemonJoinsCluster informs the daemon has joined the cluster and provides
// the handler to query the cluster component
func (daemon *Daemon) DaemonJoinsCluster(clusterProvider cluster.Provider) {
daemon.setClusterProvider(clusterProvider)
}
// DaemonLeavesCluster informs the daemon has left the cluster
func (daemon *Daemon) DaemonLeavesCluster() {
// Daemon is in charge of removing the attachable networks with
// connected containers when the node leaves the swarm
daemon.clearAttachableNetworks()
// We no longer need the cluster provider, stop it now so that
// the network agent will stop listening to cluster events.
daemon.setClusterProvider(nil)
// Wait for the networking cluster agent to stop
daemon.netController.AgentStopWait()
// Daemon is in charge of removing the ingress network when the
// node leaves the swarm. Wait for job to be done or timeout.
// This is called also on graceful daemon shutdown. We need to
// wait, because the ingress release has to happen before the
// network controller is stopped.
if done, err := daemon.ReleaseIngress(); err == nil {
timeout := time.NewTimer(5 * time.Second)
defer timeout.Stop()
select {
case <-done:
case <-timeout.C:
logrus.Warn("timeout while waiting for ingress network removal")
}
} else {
logrus.Warnf("failed to initiate ingress network removal: %v", err)
}
daemon.attachmentStore.ClearAttachments()
}
// setClusterProvider sets a component for querying the current cluster state.
func (daemon *Daemon) setClusterProvider(clusterProvider cluster.Provider) {
daemon.clusterProvider = clusterProvider
daemon.netController.SetClusterProvider(clusterProvider)
daemon.attachableNetworkLock = locker.New()
}
// IsSwarmCompatible verifies if the current daemon
// configuration is compatible with the swarm mode
func (daemon *Daemon) IsSwarmCompatible() error {
if daemon.configStore == nil {
return nil
}
return daemon.configStore.IsSwarmCompatible()
}
// NewDaemon sets up everything for the daemon to be able to service
// requests from the webserver.
func NewDaemon(ctx context.Context, config *config.Config, pluginStore *plugin.Store) (daemon *Daemon, err error) {
setDefaultMtu(config)
registryService, err := registry.NewService(config.ServiceOptions)
if err != nil {
return nil, err
}
// Ensure that we have a correct root key limit for launching containers.
if err := ModifyRootKeyLimit(); err != nil {
logrus.Warnf("unable to modify root key limit, number of containers could be limited by this quota: %v", err)
}
// Ensure we have compatible and valid configuration options
if err := verifyDaemonSettings(config); err != nil {
return nil, err
}
// Do we have a disabled network?
config.DisableBridge = isBridgeNetworkDisabled(config)
// Setup the resolv.conf
setupResolvConf(config)
// Verify the platform is supported as a daemon
if !platformSupported {
return nil, errSystemNotSupported
}
// Validate platform-specific requirements
if err := checkSystem(); err != nil {
return nil, err
}
idMapping, err := setupRemappedRoot(config)
if err != nil {
return nil, err
}
rootIDs := idMapping.RootPair()
if err := setupDaemonProcess(config); err != nil {
return nil, err
}
// set up the tmpDir to use a canonical path
tmp, err := prepareTempDir(config.Root)
if err != nil {
return nil, fmt.Errorf("Unable to get the TempDir under %s: %s", config.Root, err)
}
realTmp, err := fileutils.ReadSymlinkedDirectory(tmp)
if err != nil {
return nil, fmt.Errorf("Unable to get the full path to the TempDir (%s): %s", tmp, err)
}
if isWindows {
if _, err := os.Stat(realTmp); err != nil && os.IsNotExist(err) {
if err := system.MkdirAll(realTmp, 0700); err != nil {
return nil, fmt.Errorf("Unable to create the TempDir (%s): %s", realTmp, err)
}
}
os.Setenv("TEMP", realTmp)
os.Setenv("TMP", realTmp)
} else {
os.Setenv("TMPDIR", realTmp)
}
d := &Daemon{
configStore: config,
PluginStore: pluginStore,
startupDone: make(chan struct{}),
}
// Ensure the daemon is properly shutdown if there is a failure during
// initialization
defer func() {
if err != nil {
if err := d.Shutdown(); err != nil {
logrus.Error(err)
}
}
}()
if err := d.setGenericResources(config); err != nil {
return nil, err
}
// set up SIGUSR1 handler on Unix-like systems, or a Win32 global event
// on Windows to dump Go routine stacks
stackDumpDir := config.Root
if execRoot := config.GetExecRoot(); execRoot != "" {
stackDumpDir = execRoot
}
d.setupDumpStackTrap(stackDumpDir)
if err := d.setupSeccompProfile(); err != nil {
return nil, err
}
// Set the default isolation mode (only applicable on Windows)
if err := d.setDefaultIsolation(); err != nil {
return nil, fmt.Errorf("error setting default isolation mode: %v", err)
}
if err := configureMaxThreads(config); err != nil {
logrus.Warnf("Failed to configure golang's threads limit: %v", err)
}
// ensureDefaultAppArmorProfile does nothing if apparmor is disabled
if err := ensureDefaultAppArmorProfile(); err != nil {
logrus.Errorf(err.Error())
}
daemonRepo := filepath.Join(config.Root, "containers")
if err := idtools.MkdirAllAndChown(daemonRepo, 0710, idtools.Identity{
UID: idtools.CurrentIdentity().UID,
GID: rootIDs.GID,
}); err != nil {
return nil, err
}
// Create the directory where we'll store the runtime scripts (i.e. in
// order to support runtimeArgs)
daemonRuntimes := filepath.Join(config.Root, "runtimes")
if err := system.MkdirAll(daemonRuntimes, 0700); err != nil {
return nil, err
}
if err := d.loadRuntimes(); err != nil {
return nil, err
}
if isWindows {
if err := system.MkdirAll(filepath.Join(config.Root, "credentialspecs"), 0); err != nil {
return nil, err
}
}
// On Windows we don't support the environment variable, or a user supplied graphdriver
// as Windows has no choice in terms of which graphdrivers to use. It's a case of
// running Windows containers on Windows - windowsfilter, running Linux containers on Windows,
// lcow. Unix platforms however run a single graphdriver for all containers, and it can
// be set through an environment variable, a daemon start parameter, or chosen through
// initialization of the layerstore through driver priority order for example.
d.graphDrivers = make(map[string]string)
layerStores := make(map[string]layer.Store)
if isWindows {
d.graphDrivers[runtime.GOOS] = "windowsfilter"
if system.LCOWSupported() {
d.graphDrivers["linux"] = "lcow"
}
} else {
driverName := os.Getenv("DOCKER_DRIVER")
if driverName == "" {
driverName = config.GraphDriver
} else {
logrus.Infof("Setting the storage driver from the $DOCKER_DRIVER environment variable (%s)", driverName)
}
d.graphDrivers[runtime.GOOS] = driverName // May still be empty. Layerstore init determines instead.
}
d.RegistryService = registryService
logger.RegisterPluginGetter(d.PluginStore)
metricsSockPath, err := d.listenMetricsSock()
if err != nil {
return nil, err
}
registerMetricsPluginCallback(d.PluginStore, metricsSockPath)
backoffConfig := backoff.DefaultConfig
backoffConfig.MaxDelay = 3 * time.Second
connParams := grpc.ConnectParams{
Backoff: backoffConfig,
}
gopts := []grpc.DialOption{
// WithBlock makes sure that the following containerd request
// is reliable.
//
// NOTE: In one edge case with high load pressure, kernel kills
// dockerd, containerd and containerd-shims caused by OOM.
// When both dockerd and containerd restart, but containerd
// will take time to recover all the existing containers. Before
// containerd serving, dockerd will failed with gRPC error.
// That bad thing is that restore action will still ignore the
// any non-NotFound errors and returns running state for
// already stopped container. It is unexpected behavior. And
// we need to restart dockerd to make sure that anything is OK.
//
// It is painful. Add WithBlock can prevent the edge case. And
// n common case, the containerd will be serving in shortly.
// It is not harm to add WithBlock for containerd connection.
grpc.WithBlock(),
grpc.WithInsecure(),
grpc.WithConnectParams(connParams),
grpc.WithContextDialer(dialer.ContextDialer),
// TODO(stevvooe): We may need to allow configuration of this on the client.
grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(defaults.DefaultMaxRecvMsgSize)),
grpc.WithDefaultCallOptions(grpc.MaxCallSendMsgSize(defaults.DefaultMaxSendMsgSize)),
}
if config.ContainerdAddr != "" {
d.containerdCli, err = containerd.New(config.ContainerdAddr, containerd.WithDefaultNamespace(config.ContainerdNamespace), containerd.WithDialOpts(gopts), containerd.WithTimeout(60*time.Second))
if err != nil {
return nil, errors.Wrapf(err, "failed to dial %q", config.ContainerdAddr)
}
}
createPluginExec := func(m *plugin.Manager) (plugin.Executor, error) {
var pluginCli *containerd.Client
// Windows is not currently using containerd, keep the
// client as nil
if config.ContainerdAddr != "" {
pluginCli, err = containerd.New(config.ContainerdAddr, containerd.WithDefaultNamespace(config.ContainerdPluginNamespace), containerd.WithDialOpts(gopts), containerd.WithTimeout(60*time.Second))
if err != nil {
return nil, errors.Wrapf(err, "failed to dial %q", config.ContainerdAddr)
}
}
var rt types.Runtime
if runtime.GOOS != "windows" {
rtPtr, err := d.getRuntime(config.GetDefaultRuntimeName())
if err != nil {
return nil, err
}
rt = *rtPtr
}
return pluginexec.New(ctx, getPluginExecRoot(config.Root), pluginCli, config.ContainerdPluginNamespace, m, rt)
}
// Plugin system initialization should happen before restore. Do not change order.
d.pluginManager, err = plugin.NewManager(plugin.ManagerConfig{
Root: filepath.Join(config.Root, "plugins"),
ExecRoot: getPluginExecRoot(config.Root),
Store: d.PluginStore,
CreateExecutor: createPluginExec,
RegistryService: registryService,
LiveRestoreEnabled: config.LiveRestoreEnabled,
LogPluginEvent: d.LogPluginEvent, // todo: make private
AuthzMiddleware: config.AuthzMiddleware,
})
if err != nil {
return nil, errors.Wrap(err, "couldn't create plugin manager")
}
if err := d.setupDefaultLogConfig(); err != nil {
return nil, err
}
for operatingSystem, gd := range d.graphDrivers {
layerStores[operatingSystem], err = layer.NewStoreFromOptions(layer.StoreOptions{
Root: config.Root,
MetadataStorePathTemplate: filepath.Join(config.Root, "image", "%s", "layerdb"),
GraphDriver: gd,
GraphDriverOptions: config.GraphOptions,
IDMapping: idMapping,
PluginGetter: d.PluginStore,
ExperimentalEnabled: config.Experimental,
OS: operatingSystem,
})
if err != nil {
return nil, err
}
// As layerstore initialization may set the driver
d.graphDrivers[operatingSystem] = layerStores[operatingSystem].DriverName()
}
// Configure and validate the kernels security support. Note this is a Linux/FreeBSD
// operation only, so it is safe to pass *just* the runtime OS graphdriver.
if err := configureKernelSecuritySupport(config, d.graphDrivers[runtime.GOOS]); err != nil {
return nil, err
}
imageRoot := filepath.Join(config.Root, "image", d.graphDrivers[runtime.GOOS])
ifs, err := image.NewFSStoreBackend(filepath.Join(imageRoot, "imagedb"))
if err != nil {
return nil, err
}
lgrMap := make(map[string]image.LayerGetReleaser)
for los, ls := range layerStores {
lgrMap[los] = ls
}
imageStore, err := image.NewImageStore(ifs, lgrMap)
if err != nil {
return nil, err
}
d.volumes, err = volumesservice.NewVolumeService(config.Root, d.PluginStore, rootIDs, d)
if err != nil {
return nil, err
}
trustKey, err := loadOrCreateTrustKey(config.TrustKeyPath)
if err != nil {
return nil, err
}
trustDir := filepath.Join(config.Root, "trust")
if err := system.MkdirAll(trustDir, 0700); err != nil {
return nil, err
}
// We have a single tag/reference store for the daemon globally. However, it's
// stored under the graphdriver. On host platforms which only support a single
// container OS, but multiple selectable graphdrivers, this means depending on which
// graphdriver is chosen, the global reference store is under there. For
// platforms which support multiple container operating systems, this is slightly
// more problematic as where does the global ref store get located? Fortunately,
// for Windows, which is currently the only daemon supporting multiple container
// operating systems, the list of graphdrivers available isn't user configurable.
// For backwards compatibility, we just put it under the windowsfilter
// directory regardless.
refStoreLocation := filepath.Join(imageRoot, `repositories.json`)
rs, err := refstore.NewReferenceStore(refStoreLocation)
if err != nil {
return nil, fmt.Errorf("Couldn't create reference store repository: %s", err)
}
distributionMetadataStore, err := dmetadata.NewFSMetadataStore(filepath.Join(imageRoot, "distribution"))
if err != nil {
return nil, err
}
// Discovery is only enabled when the daemon is launched with an address to advertise. When
// initialized, the daemon is registered and we can store the discovery backend as it's read-only
if err := d.initDiscovery(config); err != nil {
return nil, err
}
sysInfo := d.RawSysInfo(false)
// Check if Devices cgroup is mounted, it is hard requirement for container security,
// on Linux.
if runtime.GOOS == "linux" && !sysInfo.CgroupDevicesEnabled && !sys.RunningInUserNS() {
return nil, errors.New("Devices cgroup isn't mounted")
}
d.ID = trustKey.PublicKey().KeyID()
d.repository = daemonRepo
d.containers = container.NewMemoryStore()
if d.containersReplica, err = container.NewViewDB(); err != nil {
return nil, err
}
d.execCommands = exec.NewStore()
d.idIndex = truncindex.NewTruncIndex([]string{})
d.statsCollector = d.newStatsCollector(1 * time.Second)
d.EventsService = events.New()
d.root = config.Root
d.idMapping = idMapping
d.seccompEnabled = sysInfo.Seccomp
d.apparmorEnabled = sysInfo.AppArmor
d.linkIndex = newLinkIndex()
imgSvcConfig := images.ImageServiceConfig{
ContainerStore: d.containers,
DistributionMetadataStore: distributionMetadataStore,
EventsService: d.EventsService,
ImageStore: imageStore,
LayerStores: layerStores,
MaxConcurrentDownloads: *config.MaxConcurrentDownloads,
MaxConcurrentUploads: *config.MaxConcurrentUploads,
MaxDownloadAttempts: *config.MaxDownloadAttempts,
ReferenceStore: rs,
RegistryService: registryService,
TrustKey: trustKey,
ContentNamespace: config.ContainerdNamespace,
}
// containerd is not currently supported with Windows.
// So sometimes d.containerdCli will be nil
// In that case we'll create a local content store... but otherwise we'll use containerd
if d.containerdCli != nil {
imgSvcConfig.Leases = d.containerdCli.LeasesService()
imgSvcConfig.ContentStore = d.containerdCli.ContentStore()
} else {
cs, lm, err := d.configureLocalContentStore(config.ContainerdNamespace)
if err != nil {
return nil, err
}
imgSvcConfig.ContentStore = cs
imgSvcConfig.Leases = lm
}
// TODO: imageStore, distributionMetadataStore, and ReferenceStore are only
// used above to run migration. They could be initialized in ImageService
// if migration is called from daemon/images. layerStore might move as well.
d.imageService = images.NewImageService(imgSvcConfig)
go d.execCommandGC()
d.containerd, err = libcontainerd.NewClient(ctx, d.containerdCli, filepath.Join(config.ExecRoot, "containerd"), config.ContainerdNamespace, d)
if err != nil {
return nil, err
}
if err := d.restore(); err != nil {
return nil, err
}
close(d.startupDone)
info := d.SystemInfo()
engineInfo.WithValues(
dockerversion.Version,
dockerversion.GitCommit,
info.Architecture,
info.Driver,
info.KernelVersion,
info.OperatingSystem,
info.OSType,
info.OSVersion,
info.ID,
).Set(1)
engineCpus.Set(float64(info.NCPU))
engineMemory.Set(float64(info.MemTotal))
gd := ""
for os, driver := range d.graphDrivers {
if len(gd) > 0 {
gd += ", "
}
gd += driver
if len(d.graphDrivers) > 1 {
gd = fmt.Sprintf("%s (%s)", gd, os)
}
}
logrus.WithFields(logrus.Fields{
"version": dockerversion.Version,
"commit": dockerversion.GitCommit,
"graphdriver(s)": gd,
}).Info("Docker daemon")
return d, nil
}
// DistributionServices returns services controlling daemon storage
func (daemon *Daemon) DistributionServices() images.DistributionServices {
return daemon.imageService.DistributionServices()
}
func (daemon *Daemon) waitForStartupDone() {
<-daemon.startupDone
}
func (daemon *Daemon) shutdownContainer(c *container.Container) error {
stopTimeout := c.StopTimeout()
// If container failed to exit in stopTimeout seconds of SIGTERM, then using the force
if err := daemon.containerStop(c, stopTimeout); err != nil {
return fmt.Errorf("Failed to stop container %s with error: %v", c.ID, err)
}
// Wait without timeout for the container to exit.
// Ignore the result.
<-c.Wait(context.Background(), container.WaitConditionNotRunning)
return nil
}
// ShutdownTimeout returns the timeout (in seconds) before containers are forcibly
// killed during shutdown. The default timeout can be configured both on the daemon
// and per container, and the longest timeout will be used. A grace-period of
// 5 seconds is added to the configured timeout.
//
// A negative (-1) timeout means "indefinitely", which means that containers
// are not forcibly killed, and the daemon shuts down after all containers exit.
func (daemon *Daemon) ShutdownTimeout() int {
shutdownTimeout := daemon.configStore.ShutdownTimeout
if shutdownTimeout < 0 {
return -1
}
if daemon.containers == nil {
return shutdownTimeout
}
graceTimeout := 5
for _, c := range daemon.containers.List() {
stopTimeout := c.StopTimeout()
if stopTimeout < 0 {
return -1
}
if stopTimeout+graceTimeout > shutdownTimeout {
shutdownTimeout = stopTimeout + graceTimeout
}
}
return shutdownTimeout
}
// Shutdown stops the daemon.
func (daemon *Daemon) Shutdown() error {
daemon.shutdown = true
// Keep mounts and networking running on daemon shutdown if
// we are to keep containers running and restore them.
if daemon.configStore.LiveRestoreEnabled && daemon.containers != nil {
// check if there are any running containers, if none we should do some cleanup
if ls, err := daemon.Containers(&types.ContainerListOptions{}); len(ls) != 0 || err != nil {
// metrics plugins still need some cleanup
daemon.cleanupMetricsPlugins()
return nil
}
}
if daemon.containers != nil {
logrus.Debugf("daemon configured with a %d seconds minimum shutdown timeout", daemon.configStore.ShutdownTimeout)
logrus.Debugf("start clean shutdown of all containers with a %d seconds timeout...", daemon.ShutdownTimeout())
daemon.containers.ApplyAll(func(c *container.Container) {
if !c.IsRunning() {
return
}
log := logrus.WithField("container", c.ID)
log.Debug("shutting down container")
if err := daemon.shutdownContainer(c); err != nil {
log.WithError(err).Error("failed to shut down container")
return
}
if mountid, err := daemon.imageService.GetLayerMountID(c.ID, c.OS); err == nil {
daemon.cleanupMountsByID(mountid)
}
log.Debugf("shut down container")
})
}
if daemon.volumes != nil {
if err := daemon.volumes.Shutdown(); err != nil {
logrus.Errorf("Error shutting down volume store: %v", err)
}
}
if daemon.imageService != nil {
daemon.imageService.Cleanup()
}
// If we are part of a cluster, clean up cluster's stuff
if daemon.clusterProvider != nil {
logrus.Debugf("start clean shutdown of cluster resources...")
daemon.DaemonLeavesCluster()
}
daemon.cleanupMetricsPlugins()
// Shutdown plugins after containers and layerstore. Don't change the order.
daemon.pluginShutdown()
// trigger libnetwork Stop only if it's initialized
if daemon.netController != nil {
daemon.netController.Stop()
}
if daemon.containerdCli != nil {
daemon.containerdCli.Close()
}
if daemon.mdDB != nil {
daemon.mdDB.Close()
}
return daemon.cleanupMounts()
}
// Mount sets container.BaseFS
// (is it not set coming in? why is it unset?)
func (daemon *Daemon) Mount(container *container.Container) error {
if container.RWLayer == nil {
return errors.New("RWLayer of container " + container.ID + " is unexpectedly nil")
}
dir, err := container.RWLayer.Mount(container.GetMountLabel())
if err != nil {
return err
}
logrus.WithField("container", container.ID).Debugf("container mounted via layerStore: %v", dir)
if container.BaseFS != nil && container.BaseFS.Path() != dir.Path() {
// The mount path reported by the graph driver should always be trusted on Windows, since the
// volume path for a given mounted layer may change over time. This should only be an error
// on non-Windows operating systems.
if runtime.GOOS != "windows" {
daemon.Unmount(container)
return fmt.Errorf("Error: driver %s is returning inconsistent paths for container %s ('%s' then '%s')",
daemon.imageService.GraphDriverForOS(container.OS), container.ID, container.BaseFS, dir)
}
}
container.BaseFS = dir // TODO: combine these fields
return nil
}
// Unmount unsets the container base filesystem
func (daemon *Daemon) Unmount(container *container.Container) error {
if container.RWLayer == nil {
return errors.New("RWLayer of container " + container.ID + " is unexpectedly nil")
}
if err := container.RWLayer.Unmount(); err != nil {
logrus.WithField("container", container.ID).WithError(err).Error("error unmounting container")
return err
}
return nil
}
// Subnets return the IPv4 and IPv6 subnets of networks that are manager by Docker.
func (daemon *Daemon) Subnets() ([]net.IPNet, []net.IPNet) {
var v4Subnets []net.IPNet
var v6Subnets []net.IPNet
managedNetworks := daemon.netController.Networks()
for _, managedNetwork := range managedNetworks {
v4infos, v6infos := managedNetwork.Info().IpamInfo()
for _, info := range v4infos {
if info.IPAMData.Pool != nil {
v4Subnets = append(v4Subnets, *info.IPAMData.Pool)
}
}
for _, info := range v6infos {
if info.IPAMData.Pool != nil {
v6Subnets = append(v6Subnets, *info.IPAMData.Pool)
}
}
}
return v4Subnets, v6Subnets
}
// prepareTempDir prepares and returns the default directory to use
// for temporary files.
// If it doesn't exist, it is created. If it exists, its content is removed.
func prepareTempDir(rootDir string) (string, error) {
var tmpDir string
if tmpDir = os.Getenv("DOCKER_TMPDIR"); tmpDir == "" {
tmpDir = filepath.Join(rootDir, "tmp")
newName := tmpDir + "-old"
if err := os.Rename(tmpDir, newName); err == nil {
go func() {
if err := os.RemoveAll(newName); err != nil {
logrus.Warnf("failed to delete old tmp directory: %s", newName)
}
}()
} else if !os.IsNotExist(err) {
logrus.Warnf("failed to rename %s for background deletion: %s. Deleting synchronously", tmpDir, err)
if err := os.RemoveAll(tmpDir); err != nil {
logrus.Warnf("failed to delete old tmp directory: %s", tmpDir)
}
}
}
return tmpDir, idtools.MkdirAllAndChown(tmpDir, 0700, idtools.CurrentIdentity())
}
func (daemon *Daemon) setGenericResources(conf *config.Config) error {
genericResources, err := config.ParseGenericResources(conf.NodeGenericResources)
if err != nil {
return err
}
daemon.genericResources = genericResources
return nil
}
func setDefaultMtu(conf *config.Config) {
// do nothing if the config does not have the default 0 value.
if conf.Mtu != 0 {
return
}
conf.Mtu = config.DefaultNetworkMtu
}
// IsShuttingDown tells whether the daemon is shutting down or not
func (daemon *Daemon) IsShuttingDown() bool {
return daemon.shutdown
}
// initDiscovery initializes the discovery watcher for this daemon.
func (daemon *Daemon) initDiscovery(conf *config.Config) error {
advertise, err := config.ParseClusterAdvertiseSettings(conf.ClusterStore, conf.ClusterAdvertise)
if err != nil {
if err == discovery.ErrDiscoveryDisabled {
return nil
}
return err
}
conf.ClusterAdvertise = advertise
discoveryWatcher, err := discovery.Init(conf.ClusterStore, conf.ClusterAdvertise, conf.ClusterOpts)
if err != nil {
return fmt.Errorf("discovery initialization failed (%v)", err)
}
daemon.discoveryWatcher = discoveryWatcher
return nil
}
func isBridgeNetworkDisabled(conf *config.Config) bool {
return conf.BridgeConfig.Iface == config.DisableNetworkBridge
}
func (daemon *Daemon) networkOptions(dconfig *config.Config, pg plugingetter.PluginGetter, activeSandboxes map[string]interface{}) ([]nwconfig.Option, error) {
options := []nwconfig.Option{}
if dconfig == nil {
return options, nil
}
options = append(options, nwconfig.OptionExperimental(dconfig.Experimental))
options = append(options, nwconfig.OptionDataDir(dconfig.Root))
options = append(options, nwconfig.OptionExecRoot(dconfig.GetExecRoot()))
dd := runconfig.DefaultDaemonNetworkMode()
dn := runconfig.DefaultDaemonNetworkMode().NetworkName()
options = append(options, nwconfig.OptionDefaultDriver(string(dd)))
options = append(options, nwconfig.OptionDefaultNetwork(dn))
if strings.TrimSpace(dconfig.ClusterStore) != "" {
kv := strings.Split(dconfig.ClusterStore, "://")
if len(kv) != 2 {
return nil, errors.New("kv store daemon config must be of the form KV-PROVIDER://KV-URL")
}
options = append(options, nwconfig.OptionKVProvider(kv[0]))
options = append(options, nwconfig.OptionKVProviderURL(kv[1]))
}
if len(dconfig.ClusterOpts) > 0 {
options = append(options, nwconfig.OptionKVOpts(dconfig.ClusterOpts))
}
if daemon.discoveryWatcher != nil {
options = append(options, nwconfig.OptionDiscoveryWatcher(daemon.discoveryWatcher))
}
if dconfig.ClusterAdvertise != "" {
options = append(options, nwconfig.OptionDiscoveryAddress(dconfig.ClusterAdvertise))
}
options = append(options, nwconfig.OptionLabels(dconfig.Labels))
options = append(options, driverOptions(dconfig)...)
if len(dconfig.NetworkConfig.DefaultAddressPools.Value()) > 0 {
options = append(options, nwconfig.OptionDefaultAddressPoolConfig(dconfig.NetworkConfig.DefaultAddressPools.Value()))
}
if daemon.configStore != nil && daemon.configStore.LiveRestoreEnabled && len(activeSandboxes) != 0 {
options = append(options, nwconfig.OptionActiveSandboxes(activeSandboxes))
}
if pg != nil {
options = append(options, nwconfig.OptionPluginGetter(pg))
}
options = append(options, nwconfig.OptionNetworkControlPlaneMTU(dconfig.NetworkControlPlaneMTU))
return options, nil
}
// GetCluster returns the cluster
func (daemon *Daemon) GetCluster() Cluster {
return daemon.cluster
}
// SetCluster sets the cluster
func (daemon *Daemon) SetCluster(cluster Cluster) {
daemon.cluster = cluster
}
func (daemon *Daemon) pluginShutdown() {
manager := daemon.pluginManager
// Check for a valid manager object. In error conditions, daemon init can fail
// and shutdown called, before plugin manager is initialized.
if manager != nil {
manager.Shutdown()
}
}
// PluginManager returns current pluginManager associated with the daemon
func (daemon *Daemon) PluginManager() *plugin.Manager { // set up before daemon to avoid this method
return daemon.pluginManager
}
// PluginGetter returns current pluginStore associated with the daemon
func (daemon *Daemon) PluginGetter() *plugin.Store {
return daemon.PluginStore
}
// CreateDaemonRoot creates the root for the daemon
func CreateDaemonRoot(config *config.Config) error {
// get the canonical path to the Docker root directory
var realRoot string
if _, err := os.Stat(config.Root); err != nil && os.IsNotExist(err) {
realRoot = config.Root
} else {
realRoot, err = fileutils.ReadSymlinkedDirectory(config.Root)
if err != nil {
return fmt.Errorf("Unable to get the full path to root (%s): %s", config.Root, err)
}
}
idMapping, err := setupRemappedRoot(config)
if err != nil {
return err
}
return setupDaemonRoot(config, realRoot, idMapping.RootPair())
}
// checkpointAndSave grabs a container lock to safely call container.CheckpointTo
func (daemon *Daemon) checkpointAndSave(container *container.Container) error {
container.Lock()
defer container.Unlock()
if err := container.CheckpointTo(daemon.containersReplica); err != nil {
return fmt.Errorf("Error saving container state: %v", err)
}
return nil
}
// because the CLI sends a -1 when it wants to unset the swappiness value
// we need to clear it on the server side
func fixMemorySwappiness(resources *containertypes.Resources) {
if resources.MemorySwappiness != nil && *resources.MemorySwappiness == -1 {
resources.MemorySwappiness = nil
}
}
// GetAttachmentStore returns current attachment store associated with the daemon
func (daemon *Daemon) GetAttachmentStore() *network.AttachmentStore {
return &daemon.attachmentStore
}
// IdentityMapping returns uid/gid mapping or a SID (in the case of Windows) for the builder
func (daemon *Daemon) IdentityMapping() *idtools.IdentityMapping {
return daemon.idMapping
}
// ImageService returns the Daemon's ImageService
func (daemon *Daemon) ImageService() *images.ImageService {
return daemon.imageService
}
// BuilderBackend returns the backend used by builder
func (daemon *Daemon) BuilderBackend() builder.Backend {
return struct {
*Daemon
*images.ImageService
}{daemon, daemon.imageService}
}