Merge pull request #2350 from mheon/lock_renumber

Add lock renumbering

1 files changed, 57 insertions, 0 deletions

diff --git a/libpod/runtime_renumber.go b/libpod/runtime_renumber.go
new file mode 100644
index 000000000..125cf0825
--- /dev/null
+++ b/libpod/runtime_renumber.go
@@ -0,0 +1,57 @@
+package libpod
+
+import (
+	"github.com/pkg/errors"
+)
+
+// renumberLocks reassigns lock numbers for all containers and pods in the
+// state.
+// TODO: It would be desirable to make it impossible to call this until all
+// other libpod sessions are dead.
+// Possibly use a read-write file lock, with all non-renumber podmans owning the
+// lock as read, renumber attempting to take a write lock?
+// The alternative is some sort of session tracking, and I don't know how
+// reliable that can be.
+func (r *Runtime) renumberLocks() error {
+	// Start off by deallocating all locks
+	if err := r.lockManager.FreeAllLocks(); err != nil {
+		return err
+	}
+
+	allCtrs, err := r.state.AllContainers()
+	if err != nil {
+		return err
+	}
+	for _, ctr := range allCtrs {
+		lock, err := r.lockManager.AllocateLock()
+		if err != nil {
+			return errors.Wrapf(err, "error allocating lock for container %s", ctr.ID())
+		}
+
+		ctr.config.LockID = lock.ID()
+
+		// Write the new lock ID
+		if err := r.state.RewriteContainerConfig(ctr, ctr.config); err != nil {
+			return err
+		}
+	}
+	allPods, err := r.state.AllPods()
+	if err != nil {
+		return err
+	}
+	for _, pod := range allPods {
+		lock, err := r.lockManager.AllocateLock()
+		if err != nil {
+			return errors.Wrapf(err, "error allocating lock for pod %s", pod.ID())
+		}
+
+		pod.config.LockID = lock.ID()
+
+		// Write the new lock ID
+		if err := r.state.RewritePodConfig(pod, pod.config); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}