diff options
Diffstat (limited to 'libpod/runtime_ctr.go')
-rw-r--r-- | libpod/runtime_ctr.go | 113 |
1 files changed, 15 insertions, 98 deletions
diff --git a/libpod/runtime_ctr.go b/libpod/runtime_ctr.go index 8bf862bf2..301c4627d 100644 --- a/libpod/runtime_ctr.go +++ b/libpod/runtime_ctr.go @@ -74,8 +74,7 @@ func (r *Runtime) RestoreContainer(ctx context.Context, rSpec *spec.Spec, config } // RenameContainer renames the given container. -// The given container object will be rendered unusable, and a new, renamed -// Container will be returned. +// Returns a copy of the container that has been renamed if successful. func (r *Runtime) RenameContainer(ctx context.Context, ctr *Container, newName string) (*Container, error) { ctr.lock.Lock() defer ctr.lock.Unlock() @@ -88,26 +87,6 @@ func (r *Runtime) RenameContainer(ctx context.Context, ctr *Container, newName s return nil, define.RegexError } - // Check if the name is available. - // This is *100% NOT ATOMIC* so any failures in-flight will do - // *VERY BAD THINGS* to the state. So we have to try and catch all we - // can before starting. - if _, err := r.state.LookupContainerID(newName); err == nil { - return nil, errors.Wrapf(define.ErrCtrExists, "name %s is already in use by another container", newName) - } - if _, err := r.state.LookupPod(newName); err == nil { - return nil, errors.Wrapf(define.ErrPodExists, "name %s is already in use by another pod", newName) - } - - // TODO: Investigate if it is possible to remove this limitation. - depCtrs, err := r.state.ContainerInUse(ctr) - if err != nil { - return nil, err - } - if len(depCtrs) > 0 { - return nil, errors.Wrapf(define.ErrCtrExists, "cannot rename container %s as it is in use by other containers: %v", ctr.ID(), strings.Join(depCtrs, ",")) - } - // We need to pull an updated config, in case another rename fired and // the config was re-written. newConf, err := r.state.GetContainerConfig(ctr.ID()) @@ -116,95 +95,33 @@ func (r *Runtime) RenameContainer(ctx context.Context, ctr *Container, newName s } ctr.config = newConf - // TODO: This is going to fail if we have active exec sessions, too. - // Investigate fixing that at a later date. - - var pod *Pod - if ctr.config.Pod != "" { - tmpPod, err := r.state.Pod(ctr.config.Pod) - if err != nil { - return nil, errors.Wrapf(err, "error retrieving container %s pod", ctr.ID()) - } - pod = tmpPod - // Lock pod to ensure it's not removed while we're working - pod.lock.Lock() - defer pod.lock.Unlock() - } - - // Lock all volumes to ensure they are not removed while we're working - volsLocked := make(map[string]bool) - for _, namedVol := range ctr.config.NamedVolumes { - if volsLocked[namedVol.Name] { - continue - } - vol, err := r.state.Volume(namedVol.Name) - if err != nil { - return nil, errors.Wrapf(err, "error retrieving volume used by container %s", ctr.ID()) - } - - volsLocked[vol.Name()] = true - vol.lock.Lock() - defer vol.lock.Unlock() - } - logrus.Infof("Going to rename container %s from %q to %q", ctr.ID(), ctr.Name(), newName) - // Step 1: remove the old container. - if pod != nil { - if err := r.state.RemoveContainerFromPod(pod, ctr); err != nil { - return nil, errors.Wrapf(err, "error renaming container %s", ctr.ID()) - } - } else { - if err := r.state.RemoveContainer(ctr); err != nil { - return nil, errors.Wrapf(err, "error renaming container %s", ctr.ID()) - } - } - - // Step 2: Make a new container based on the old one. - // TODO: Should we deep-copy the container config and state, to be safe? - newCtr := new(Container) - newCtr.config = ctr.config - newCtr.state = ctr.state - newCtr.lock = ctr.lock - newCtr.ociRuntime = ctr.ociRuntime - newCtr.runtime = r - newCtr.rootlessSlirpSyncR = ctr.rootlessSlirpSyncR - newCtr.rootlessSlirpSyncW = ctr.rootlessSlirpSyncW - newCtr.rootlessPortSyncR = ctr.rootlessPortSyncR - newCtr.rootlessPortSyncW = ctr.rootlessPortSyncW - - newCtr.valid = true - newCtr.config.Name = newName - - // Step 3: Add that new container to the DB - if pod != nil { - if err := r.state.AddContainerToPod(pod, newCtr); err != nil { - return nil, errors.Wrapf(err, "error renaming container %s", newCtr.ID()) - } - } else { - if err := r.state.AddContainer(newCtr); err != nil { - return nil, errors.Wrapf(err, "error renaming container %s", newCtr.ID()) - } - } + // Step 1: Alter the config. Save the old name, we need it to rewrite + // the config. + oldName := ctr.config.Name + ctr.config.Name = newName - // Step 4: Save the new container, to force the state to be written to - // the DB. This may not be necessary, depending on DB implementation, - // but let's do it to be safe. - if err := newCtr.save(); err != nil { - return nil, err + // Step 2: rewrite the old container's config in the DB. + if err := r.state.SafeRewriteContainerConfig(ctr, oldName, ctr.config.Name, ctr.config); err != nil { + // Assume the rename failed. + // Set config back to the old name so reflect what is actually + // present in the DB. + ctr.config.Name = oldName + return nil, errors.Wrapf(err, "error renaming container %s", ctr.ID()) } - // Step 5: rename the container in c/storage. + // Step 3: rename the container in c/storage. // This can fail if the name is already in use by a non-Podman // container. This puts us in a bad spot - we've already renamed the // container in Podman. We can swap the order, but then we have the // opposite problem. Atomicity is a real problem here, with no easy // solution. - if err := r.store.SetNames(newCtr.ID(), []string{newCtr.Name()}); err != nil { + if err := r.store.SetNames(ctr.ID(), []string{ctr.Name()}); err != nil { return nil, err } - return newCtr, nil + return ctr, nil } func (r *Runtime) initContainerVariables(rSpec *spec.Spec, config *ContainerConfig) (*Container, error) { |