Revision history for Data-ReqRep-Shared

0.09      2026-09-25
          - Incompatible on-disk format: recreate existing files.
          - Survive processes that die, stop, exec or reuse PIDs mid-request.
          - Receiver-only replies; destroy cancels; cancel drops late replies.
          - New ready_fd/ready notification; signal handlers run during waits.
          - Anonymous channels use memfd; space reserved up front; stricter args.

0.08      2026-09-15
          - Incompatible on-disk format: recreate existing files.
          - Refuse attaching across PID namespaces or boots (see CONTAINERS).
          - Refuse a world-writable file owned by another user.
          - Fix slot leaks and lost or misdelivered replies when a cancel,
            timeout, clear or crash recovery raced a reply.
          - Fix crash recovery losing a slot when the recoverer is killed.
          - Fix lost wakeups in send_wait and get_wait.
          - Fix recv_multi, recv_wait_multi and drain losing requests on OOM.
          - Fix recv_wait_multi(0) taking a request.
          - Fix a worker killed mid-receive corrupting the next request.
          - reply returns false for a corrupt id instead of croaking.
          - new croaks after 10s instead of hanging on a held file lock.
          - Recover a lock left ownerless by a corrupt file instead of hanging.
          - eventfd setters keep their own duplicate of the descriptor.

0.07      2026-08-12
          - Fix a client receiving another client's reply. A reply copied its
            payload into the response slot before claiming it, so a cancel and
            re-acquire completing in that window let the copy overwrite the new
            owner's already-published reply; the new owner then read it as its
            own, with no error reported anywhere. A reply now takes the slot
            before writing to it.
          - Recover a file left behind by an interrupted create instead of
            leaving the path unopenable.
          - Hardening: re-entrancy with tied and overloaded arguments, and
            DESTROY on an invocant that is not one of ours.
          - Documentation and test-harness corrections.
          - unlink() reports a removal that failed; one already gone is not an
            error.

0.06      2026-07-21
          - Bound a shared slot's response length before copying it.
          - Fetch get-magic on optional arguments before testing them.

0.05  2026-07-03
    - Security and robustness hardening; backing files now created mode
      0600 (pass a file-mode argument to new() for cross-user sharing).

0.04  2026-05-27
    - slot_acquire: owner_pid CAS gates the state CAS, ACQUIRE on loads
      (fixes recovery ABA where a fresh free+acquire could clobber a live owner)
    - reply: re-check generation before publishing CAS and recover post-CAS
      via gen bump (fixes TOCTOU where cancel+re-acquire could let a reply
      land on the wrong owner's slot)
    - slot_release: two-step CAS (owner_pid mypid->0, then state from->FREE)
      prevents blind state-store from clobbering a freshly-acquired slot
    - compute_layout: resp_stride in uint64 (was wrapping for resp_data_max
      near UINT32_MAX -> replies overflowing into next slot)
    - validate_header: reject files with resp_stride too small for slot data
    - size(): read head before tail and clamp tail<head to 0
    - plug mmap/fd leak in create_int / create_int_memfd on calloc OOM


0.03  2026-04-26
    - arena underflow guard; init under flock
    - strict fd validation; harden DESTROY
    - hoist SV construction out of recv multi/drain mutex
    - class prefix on client croaks
    - eventfd consume returns count; MAKE OBJ macro fix
    - idempotent eventfd; aarch64 CI matrix


0.02  2026-04-12
    - Add SEE ALSO cross-links to family modules

0.01  2026-04-10
    - Initial release
    - Str variant: mutex-protected request queue with circular arena
    - Int variant: lock-free Vyukov MPMC request queue
    - Per-slot futex for targeted response delivery
    - Generation counter for ABA-safe cancel/recycle
    - PID-based stale lock and slot recovery
    - Dual eventfd for async EV integration
    - File-backed, anonymous, and memfd shared memory