diff options
Diffstat (limited to 'libpod/boltdb_state.go')
-rw-r--r-- | libpod/boltdb_state.go | 338 |
1 files changed, 337 insertions, 1 deletions
diff --git a/libpod/boltdb_state.go b/libpod/boltdb_state.go index 4918bf57a..2ce8e0de4 100644 --- a/libpod/boltdb_state.go +++ b/libpod/boltdb_state.go @@ -41,6 +41,8 @@ type BoltState struct { // containing the path to the container's network namespace, a dependencies // bucket containing the container's dependencies, and an optional pod key // containing the ID of the pod the container is joined to. +// After updates to include exec sessions, may also include an exec bucket +// with the IDs of exec sessions currently in use by the container. // - allCtrsBkt: Map of ID to name containing only containers. Used for // container lookup operations. // - podBkt: Contains a sub-bucket for each pod in the state. @@ -49,6 +51,10 @@ type BoltState struct { // containers in the pod. // - allPodsBkt: Map of ID to name containing only pods. Used for pod lookup // operations. +// - execBkt: Map of exec session ID to exec session - contains a sub-bucket for +// each exec session in the DB. +// - execRegistryBkt: Map of exec session ID to nothing. Contains one entry for +// each exec session. Used for iterating through all exec sessions. // - runtimeConfigBkt: Contains configuration of the libpod instance that // initially created the database. This must match for any further instances // that access the database, to ensure that state mismatches with @@ -86,6 +92,7 @@ func NewBoltState(path string, runtime *Runtime) (State, error) { allPodsBkt, volBkt, allVolsBkt, + execBkt, runtimeConfigBkt, } @@ -171,6 +178,11 @@ func (s *BoltState) Refresh() error { return err } + execBucket, err := getExecBucket(tx) + if err != nil { + return err + } + // Iterate through all IDs. Check if they are containers. // If they are, unmarshal their state, and then clear // PID, mountpoint, and state for all of them @@ -245,6 +257,26 @@ func (s *BoltState) Refresh() error { return errors.Wrapf(err, "error updating state for container %s in DB", string(id)) } + // Delete all exec sessions, if there are any + ctrExecBkt := ctrBkt.Bucket(execBkt) + if ctrExecBkt != nil { + // Can't delete in a ForEach, so build a list of + // what to remove then remove. + toRemove := []string{} + err = ctrExecBkt.ForEach(func(id, unused []byte) error { + toRemove = append(toRemove, string(id)) + return nil + }) + if err != nil { + return err + } + for _, execId := range toRemove { + if err := ctrExecBkt.Delete([]byte(execId)); err != nil { + return errors.Wrapf(err, "error removing exec session %s from container %s", execId, string(id)) + } + } + } + return nil }) if err != nil { @@ -285,7 +317,30 @@ func (s *BoltState) Refresh() error { return nil }) - return err + if err != nil { + return err + } + + // Now refresh exec sessions + // We want to remove them all, but for-each can't modify buckets + // So we have to make a list of what to operate on, then do the + // work. + toRemoveExec := []string{} + err = execBucket.ForEach(func(id, unused []byte) error { + toRemoveExec = append(toRemoveExec, string(id)) + return nil + }) + if err != nil { + return err + } + + for _, execSession := range toRemoveExec { + if err := execBucket.Delete([]byte(execSession)); err != nil { + return errors.Wrapf(err, "error deleting exec session %s registry from database", execSession) + } + } + + return nil }) return err } @@ -895,6 +950,287 @@ func (s *BoltState) GetContainerConfig(id string) (*ContainerConfig, error) { return config, nil } +// AddExecSession adds an exec session to the state. +func (s *BoltState) AddExecSession(ctr *Container, session *ExecSession) error { + if !s.valid { + return define.ErrDBClosed + } + + if !ctr.valid { + return define.ErrCtrRemoved + } + + db, err := s.getDBCon() + if err != nil { + return err + } + defer s.deferredCloseDBCon(db) + + ctrID := []byte(ctr.ID()) + sessionID := []byte(session.ID()) + + err = db.Update(func(tx *bolt.Tx) error { + execBucket, err := getExecBucket(tx) + if err != nil { + return err + } + ctrBucket, err := getCtrBucket(tx) + if err != nil { + return err + } + + dbCtr := ctrBucket.Bucket(ctrID) + if dbCtr == nil { + ctr.valid = false + return errors.Wrapf(define.ErrNoSuchCtr, "container %s is not present in the database", ctr.ID()) + } + + ctrExecSessionBucket, err := dbCtr.CreateBucketIfNotExists(execBkt) + if err != nil { + return errors.Wrapf(err, "error creating exec sessions bucket for container %s", ctr.ID()) + } + + execExists := execBucket.Get(sessionID) + if execExists != nil { + return errors.Wrapf(define.ErrExecSessionExists, "an exec session with ID %s already exists", session.ID()) + } + + if err := execBucket.Put(sessionID, ctrID); err != nil { + return errors.Wrapf(err, "error adding exec session %s to DB", session.ID()) + } + + if err := ctrExecSessionBucket.Put(sessionID, ctrID); err != nil { + return errors.Wrapf(err, "error adding exec session %s to container %s in DB", session.ID(), ctr.ID()) + } + + return nil + }) + return err +} + +// GetExecSession returns the ID of the container an exec session is associated +// with. +func (s *BoltState) GetExecSession(id string) (string, error) { + if !s.valid { + return "", define.ErrDBClosed + } + + if id == "" { + return "", define.ErrEmptyID + } + + db, err := s.getDBCon() + if err != nil { + return "", err + } + defer s.deferredCloseDBCon(db) + + ctrID := "" + err = db.View(func(tx *bolt.Tx) error { + execBucket, err := getExecBucket(tx) + if err != nil { + return err + } + + ctr := execBucket.Get([]byte(id)) + if ctr == nil { + return errors.Wrapf(define.ErrNoSuchExecSession, "no exec session with ID %s found", id) + } + ctrID = string(ctr) + return nil + }) + return ctrID, err +} + +// RemoveExecSession removes references to the given exec session in the +// database. +func (s *BoltState) RemoveExecSession(session *ExecSession) error { + if !s.valid { + return define.ErrDBClosed + } + + db, err := s.getDBCon() + if err != nil { + return err + } + defer s.deferredCloseDBCon(db) + + sessionID := []byte(session.ID()) + containerID := []byte(session.ContainerID()) + err = db.Update(func(tx *bolt.Tx) error { + execBucket, err := getExecBucket(tx) + if err != nil { + return err + } + ctrBucket, err := getCtrBucket(tx) + if err != nil { + return err + } + + sessionExists := execBucket.Get(sessionID) + if sessionExists == nil { + return define.ErrNoSuchExecSession + } + // Check that container ID matches + if string(sessionExists) != session.ContainerID() { + return errors.Wrapf(define.ErrInternal, "database inconsistency: exec session %s points to container %s in state but %s in database", session.ID(), session.ContainerID(), string(sessionExists)) + } + + if err := execBucket.Delete(sessionID); err != nil { + return errors.Wrapf(err, "error removing exec session %s from database", session.ID()) + } + + dbCtr := ctrBucket.Bucket(containerID) + if dbCtr == nil { + // State is inconsistent. We refer to a container that + // is no longer in the state. + // Return without error, to attempt to recover. + return nil + } + + ctrExecBucket := dbCtr.Bucket(execBkt) + if ctrExecBucket == nil { + // Again, state is inconsistent. We should have an exec + // bucket, and it should have this session. + // Again, nothing we can do, so proceed and try to + // recover. + return nil + } + + ctrSessionExists := ctrExecBucket.Get(sessionID) + if ctrSessionExists != nil { + if err := ctrExecBucket.Delete(sessionID); err != nil { + return errors.Wrapf(err, "error removing exec session %s from container %s in database", session.ID(), session.ContainerID()) + } + } + + return nil + }) + return err +} + +// GetContainerExecSessions retrieves the IDs of all exec sessions running in a +// container that the database is aware of (IE, were added via AddExecSession). +func (s *BoltState) GetContainerExecSessions(ctr *Container) ([]string, error) { + if !s.valid { + return nil, define.ErrDBClosed + } + + if !ctr.valid { + return nil, define.ErrCtrRemoved + } + + db, err := s.getDBCon() + if err != nil { + return nil, err + } + defer s.deferredCloseDBCon(db) + + ctrID := []byte(ctr.ID()) + sessions := []string{} + err = db.View(func(tx *bolt.Tx) error { + ctrBucket, err := getCtrBucket(tx) + if err != nil { + return err + } + + dbCtr := ctrBucket.Bucket(ctrID) + if dbCtr == nil { + ctr.valid = false + return define.ErrNoSuchCtr + } + + ctrExecSessions := dbCtr.Bucket(execBkt) + if ctrExecSessions == nil { + return nil + } + + return ctrExecSessions.ForEach(func(id, unused []byte) error { + sessions = append(sessions, string(id)) + return nil + }) + }) + if err != nil { + return nil, err + } + + return sessions, nil +} + +// RemoveContainerExecSessions removes all exec sessions attached to a given +// container. +func (s *BoltState) RemoveContainerExecSessions(ctr *Container) error { + if !s.valid { + return define.ErrDBClosed + } + + if !ctr.valid { + return define.ErrCtrRemoved + } + + db, err := s.getDBCon() + if err != nil { + return err + } + defer s.deferredCloseDBCon(db) + + ctrID := []byte(ctr.ID()) + sessions := []string{} + + err = db.Update(func(tx *bolt.Tx) error { + execBucket, err := getExecBucket(tx) + if err != nil { + return err + } + ctrBucket, err := getCtrBucket(tx) + if err != nil { + return err + } + + dbCtr := ctrBucket.Bucket(ctrID) + if dbCtr == nil { + ctr.valid = false + return define.ErrNoSuchCtr + } + + ctrExecSessions := dbCtr.Bucket(execBkt) + if ctrExecSessions == nil { + return nil + } + + err = ctrExecSessions.ForEach(func(id, unused []byte) error { + sessions = append(sessions, string(id)) + return nil + }) + if err != nil { + return err + } + + for _, session := range sessions { + if err := ctrExecSessions.Delete([]byte(session)); err != nil { + return errors.Wrapf(err, "error removing container %s exec session %s from database", ctr.ID(), session) + } + // Check if the session exists in the global table + // before removing. It should, but in cases where the DB + // has become inconsistent, we should try and proceed + // so we can recover. + sessionExists := execBucket.Get([]byte(session)) + if sessionExists == nil { + continue + } + if string(sessionExists) != ctr.ID() { + return errors.Wrapf(define.ErrInternal, "database mismatch: exec session %s is associated with containers %s and %s", session, ctr.ID(), string(sessionExists)) + } + if err := execBucket.Delete([]byte(session)); err != nil { + return errors.Wrapf(err, "error removing container %s exec session %s from exec sessions", ctr.ID(), session) + } + } + + return nil + }) + return err +} + // RewriteContainerConfig rewrites a container's configuration. // WARNING: This function is DANGEROUS. Do not use without reading the full // comment on this function in state.go. |