Module lock 

The advisory single-writer lock: a lock entry naming the process that holds the container open for writing.

Advisory on purpose. It stops the second blockworx from writing a log the first is also appending to; it does not — and is not meant to — stop the user’s text editor, which is the point of a container made of plain files.

Structs

LockHolder

Who holds the lock, as the entry records it.

Enums

Claim

The answer to “may I write this container?”.

Holder

Whether the process named in a lock entry is still running.

Holding

Who holds a container open for writing, in the words the reader is told it in.

Functions

claim

Claim the writer’s lock on storage’s container — what Storage::claim does for a storage with no lock of its own.

claim_probing 🔒

The seam the liveness probe enters by: a test can state “the holder is gone” without needing a process that reliably is.

holder 🔒

Linux answers this from /proc, which needs no dependency and no unsafe. Everywhere else the honest answer is that we cannot tell, and the safe one is to leave the lock alone: a lock wrongly broken means two writers appending to one log, while a lock wrongly kept means one read-only session and a file the user can delete.

release

Give the lock back. A release that does not land leaves a stale entry, which the next claim breaks — so there is nothing here for a caller to do about it.