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-rw-r--r--libpod/container_internal.go382
1 files changed, 382 insertions, 0 deletions
diff --git a/libpod/container_internal.go b/libpod/container_internal.go
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+++ b/libpod/container_internal.go
@@ -0,0 +1,382 @@
+package libpod
+
+import (
+ "fmt"
+ "io"
+ "os"
+ "path/filepath"
+ "syscall"
+ "time"
+
+ "github.com/containers/storage"
+ "github.com/containers/storage/pkg/archive"
+ "github.com/docker/docker/pkg/mount"
+ "github.com/docker/docker/pkg/namesgenerator"
+ "github.com/docker/docker/pkg/stringid"
+ "github.com/mrunalp/fileutils"
+ spec "github.com/opencontainers/runtime-spec/specs-go"
+ "github.com/opencontainers/selinux/go-selinux/label"
+ "github.com/pkg/errors"
+ "github.com/sirupsen/logrus"
+ "github.com/ulule/deepcopier"
+ "golang.org/x/sys/unix"
+)
+
+// rootFsSize gets the size of the container's root filesystem
+// A container FS is split into two parts. The first is the top layer, a
+// mutable layer, and the rest is the RootFS: the set of immutable layers
+// that make up the image on which the container is based.
+func (c *Container) rootFsSize() (int64, error) {
+ container, err := c.runtime.store.Container(c.ID())
+ if err != nil {
+ return 0, err
+ }
+
+ // Ignore the size of the top layer. The top layer is a mutable RW layer
+ // and is not considered a part of the rootfs
+ rwLayer, err := c.runtime.store.Layer(container.LayerID)
+ if err != nil {
+ return 0, err
+ }
+ layer, err := c.runtime.store.Layer(rwLayer.Parent)
+ if err != nil {
+ return 0, err
+ }
+
+ size := int64(0)
+ for layer.Parent != "" {
+ layerSize, err := c.runtime.store.DiffSize(layer.Parent, layer.ID)
+ if err != nil {
+ return size, errors.Wrapf(err, "getting diffsize of layer %q and its parent %q", layer.ID, layer.Parent)
+ }
+ size += layerSize
+ layer, err = c.runtime.store.Layer(layer.Parent)
+ if err != nil {
+ return 0, err
+ }
+ }
+ // Get the size of the last layer. Has to be outside of the loop
+ // because the parent of the last layer is "", andlstore.Get("")
+ // will return an error.
+ layerSize, err := c.runtime.store.DiffSize(layer.Parent, layer.ID)
+ return size + layerSize, err
+}
+
+// rwSize Gets the size of the mutable top layer of the container.
+func (c *Container) rwSize() (int64, error) {
+ container, err := c.runtime.store.Container(c.ID())
+ if err != nil {
+ return 0, err
+ }
+
+ // Get the size of the top layer by calculating the size of the diff
+ // between the layer and its parent. The top layer of a container is
+ // the only RW layer, all others are immutable
+ layer, err := c.runtime.store.Layer(container.LayerID)
+ if err != nil {
+ return 0, err
+ }
+ return c.runtime.store.DiffSize(layer.Parent, layer.ID)
+}
+
+// The path to the container's root filesystem - where the OCI spec will be
+// placed, amongst other things
+func (c *Container) bundlePath() string {
+ return c.config.StaticDir
+}
+
+// The path to the container's logs file
+func (c *Container) logPath() string {
+ return filepath.Join(c.config.StaticDir, "ctr.log")
+}
+
+// Retrieves the path of the container's attach socket
+func (c *Container) attachSocketPath() string {
+ return filepath.Join(c.runtime.ociRuntime.socketsDir, c.ID(), "attach")
+}
+
+// Sync this container with on-disk state and runc status
+// Should only be called with container lock held
+// This function should suffice to ensure a container's state is accurate and
+// it is valid for use.
+func (c *Container) syncContainer() error {
+ if err := c.runtime.state.UpdateContainer(c); err != nil {
+ return err
+ }
+ // If runc knows about the container, update its status in runc
+ // And then save back to disk
+ if (c.state.State != ContainerStateUnknown) &&
+ (c.state.State != ContainerStateConfigured) {
+ oldState := c.state.State
+ // TODO: optionally replace this with a stat for the exit file
+ if err := c.runtime.ociRuntime.updateContainerStatus(c); err != nil {
+ return err
+ }
+ // Only save back to DB if state changed
+ if c.state.State != oldState {
+ if err := c.save(); err != nil {
+ return err
+ }
+ }
+ }
+
+ if !c.valid {
+ return errors.Wrapf(ErrCtrRemoved, "container %s is not valid", c.ID())
+ }
+
+ return nil
+}
+
+// Make a new container
+func newContainer(rspec *spec.Spec, lockDir string) (*Container, error) {
+ if rspec == nil {
+ return nil, errors.Wrapf(ErrInvalidArg, "must provide a valid runtime spec to create container")
+ }
+
+ ctr := new(Container)
+ ctr.config = new(ContainerConfig)
+ ctr.state = new(containerRuntimeInfo)
+
+ ctr.config.ID = stringid.GenerateNonCryptoID()
+ ctr.config.Name = namesgenerator.GetRandomName(0)
+
+ ctr.config.Spec = new(spec.Spec)
+ deepcopier.Copy(rspec).To(ctr.config.Spec)
+ ctr.config.CreatedTime = time.Now()
+
+ ctr.config.ShmSize = DefaultShmSize
+ ctr.config.CgroupParent = CgroupParent
+
+ // Path our lock file will reside at
+ lockPath := filepath.Join(lockDir, ctr.config.ID)
+ // Grab a lockfile at the given path
+ lock, err := storage.GetLockfile(lockPath)
+ if err != nil {
+ return nil, errors.Wrapf(err, "error creating lockfile for new container")
+ }
+ ctr.lock = lock
+
+ return ctr, nil
+}
+
+// Create container root filesystem for use
+func (c *Container) setupStorage() error {
+ if !c.valid {
+ return errors.Wrapf(ErrCtrRemoved, "container %s is not valid", c.ID())
+ }
+
+ if c.state.State != ContainerStateConfigured {
+ return errors.Wrapf(ErrCtrStateInvalid, "container %s must be in Configured state to have storage set up", c.ID())
+ }
+
+ // Need both an image ID and image name, plus a bool telling us whether to use the image configuration
+ if c.config.RootfsImageID == "" || c.config.RootfsImageName == "" {
+ return errors.Wrapf(ErrInvalidArg, "must provide image ID and image name to use an image")
+ }
+
+ containerInfo, err := c.runtime.storageService.CreateContainerStorage(c.runtime.imageContext, c.config.RootfsImageName, c.config.RootfsImageID, c.config.Name, c.config.ID, c.config.MountLabel)
+ if err != nil {
+ return errors.Wrapf(err, "error creating container storage")
+ }
+
+ c.config.StaticDir = containerInfo.Dir
+ c.state.RunDir = containerInfo.RunDir
+
+ artifacts := filepath.Join(c.config.StaticDir, artifactsDir)
+ if err := os.MkdirAll(artifacts, 0755); err != nil {
+ return errors.Wrapf(err, "error creating artifacts directory %q", artifacts)
+ }
+
+ return nil
+}
+
+// Tear down a container's storage prior to removal
+func (c *Container) teardownStorage() error {
+ if !c.valid {
+ return errors.Wrapf(ErrCtrRemoved, "container %s is not valid", c.ID())
+ }
+
+ if c.state.State == ContainerStateRunning || c.state.State == ContainerStatePaused {
+ return errors.Wrapf(ErrCtrStateInvalid, "cannot remove storage for container %s as it is running or paused", c.ID())
+ }
+
+ artifacts := filepath.Join(c.config.StaticDir, artifactsDir)
+ if err := os.RemoveAll(artifacts); err != nil {
+ return errors.Wrapf(err, "error removing artifacts %q", artifacts)
+ }
+
+ if err := c.cleanupStorage(); err != nil {
+ return errors.Wrapf(err, "failed to cleanup container %s storage", c.ID())
+ }
+
+ if err := c.runtime.storageService.DeleteContainer(c.ID()); err != nil {
+ return errors.Wrapf(err, "error removing container %s root filesystem", c.ID())
+ }
+
+ return nil
+}
+
+// Refresh refreshes the container's state after a restart
+func (c *Container) refresh() error {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+
+ if !c.valid {
+ return errors.Wrapf(ErrCtrRemoved, "container %s is not valid - may have been removed", c.ID())
+ }
+
+ // We need to get the container's temporary directory from c/storage
+ // It was lost in the reboot and must be recreated
+ dir, err := c.runtime.storageService.GetRunDir(c.ID())
+ if err != nil {
+ return errors.Wrapf(err, "error retrieving temporary directory for container %s", c.ID())
+ }
+ c.state.RunDir = dir
+
+ if err := c.runtime.state.SaveContainer(c); err != nil {
+ return errors.Wrapf(err, "error refreshing state for container %s", c.ID())
+ }
+
+ return nil
+}
+
+func (c *Container) export(path string) error {
+ mountPoint := c.state.Mountpoint
+ if !c.state.Mounted {
+ mount, err := c.runtime.store.Mount(c.ID(), c.config.MountLabel)
+ if err != nil {
+ return errors.Wrapf(err, "error mounting container %q", c.ID())
+ }
+ mountPoint = mount
+ defer func() {
+ if err := c.runtime.store.Unmount(c.ID()); err != nil {
+ logrus.Errorf("error unmounting container %q: %v", c.ID(), err)
+ }
+ }()
+ }
+
+ input, err := archive.Tar(mountPoint, archive.Uncompressed)
+ if err != nil {
+ return errors.Wrapf(err, "error reading container directory %q", c.ID())
+ }
+
+ outFile, err := os.Create(path)
+ if err != nil {
+ return errors.Wrapf(err, "error creating file %q", path)
+ }
+ defer outFile.Close()
+
+ _, err = io.Copy(outFile, input)
+ return err
+}
+
+// Get path of artifact with a given name for this container
+func (c *Container) getArtifactPath(name string) string {
+ return filepath.Join(c.config.StaticDir, artifactsDir, name)
+}
+
+// Used with Wait() to determine if a container has exited
+func (c *Container) isStopped() (bool, error) {
+ if !c.locked {
+ c.lock.Lock()
+ defer c.lock.Unlock()
+ }
+ err := c.syncContainer()
+ if err != nil {
+ return true, err
+ }
+ return c.state.State == ContainerStateStopped, nil
+}
+
+// save container state to the database
+func (c *Container) save() error {
+ if err := c.runtime.state.SaveContainer(c); err != nil {
+ return errors.Wrapf(err, "error saving container %s state", c.ID())
+ }
+ return nil
+}
+
+// mountStorage sets up the container's root filesystem
+// It mounts the image and any other requested mounts
+// TODO: Add ability to override mount label so we can use this for Mount() too
+// TODO: Can we use this for export? Copying SHM into the export might not be
+// good
+func (c *Container) mountStorage() (err error) {
+ // Container already mounted, nothing to do
+ if c.state.Mounted {
+ return nil
+ }
+
+ // TODO: generalize this mount code so it will mount every mount in ctr.config.Mounts
+
+ mounted, err := mount.Mounted(c.config.ShmDir)
+ if err != nil {
+ return errors.Wrapf(err, "unable to determine if %q is mounted", c.config.ShmDir)
+ }
+
+ if !mounted {
+ shmOptions := fmt.Sprintf("mode=1777,size=%d", c.config.ShmSize)
+ if err := unix.Mount("shm", c.config.ShmDir, "tmpfs", unix.MS_NOEXEC|unix.MS_NOSUID|unix.MS_NODEV,
+ label.FormatMountLabel(shmOptions, c.config.MountLabel)); err != nil {
+ return errors.Wrapf(err, "failed to mount shm tmpfs %q", c.config.ShmDir)
+ }
+ }
+
+ mountPoint, err := c.runtime.storageService.MountContainerImage(c.ID())
+ if err != nil {
+ return errors.Wrapf(err, "error mounting storage for container %s", c.ID())
+ }
+ c.state.Mounted = true
+ c.state.Mountpoint = mountPoint
+
+ logrus.Debugf("Created root filesystem for container %s at %s", c.ID(), c.state.Mountpoint)
+
+ defer func() {
+ if err != nil {
+ if err2 := c.cleanupStorage(); err2 != nil {
+ logrus.Errorf("Error unmounting storage for container %s: %v", c.ID(), err)
+ }
+ }
+ }()
+
+ return c.save()
+}
+
+// cleanupStorage unmounts and cleans up the container's root filesystem
+func (c *Container) cleanupStorage() error {
+ if !c.state.Mounted {
+ // Already unmounted, do nothing
+ return nil
+ }
+
+ for _, mount := range c.config.Mounts {
+ if err := unix.Unmount(mount, unix.MNT_DETACH); err != nil {
+ if err != syscall.EINVAL {
+ logrus.Warnf("container %s failed to unmount %s : %v", c.ID(), mount, err)
+ }
+ }
+ }
+
+ // Also unmount storage
+ if err := c.runtime.storageService.UnmountContainerImage(c.ID()); err != nil {
+ return errors.Wrapf(err, "error unmounting container %s root filesystem", c.ID())
+ }
+
+ c.state.Mountpoint = ""
+ c.state.Mounted = false
+
+ return c.save()
+}
+
+// copyHostFileToRundir copies the provided file to the runtimedir
+func (c *Container) copyHostFileToRundir(sourcePath string) (string, error) {
+ destFileName := filepath.Join(c.state.RunDir, filepath.Base(sourcePath))
+ if err := fileutils.CopyFile(sourcePath, destFileName); err != nil {
+ return "", err
+ }
+ // Relabel runDirResolv for the container
+ if err := label.Relabel(destFileName, c.config.MountLabel, false); err != nil {
+ return "", err
+ }
+ return destFileName, nil
+}