Files
mxaccess/design
Joseph Doherty 9501080170
rust / build / test / clippy / fmt (push) Has been cancelled
[F4+F5] mxaccess-rpc: BindAck/AlterContextResponse parser + live-capture round-trip
Adds BindAckPdu + per-result BindAckResult per [C706] §12.6.3.4: u16
result + u16 reason + 20-byte SyntaxId, preceded by port_any_t secondary
address, n_results, and 3 reserved bytes. Encode/decode handle both
PacketType::BindAck and PacketType::AlterContextResponse (same body
shape).

The new bind_ack_round_trips_live_capture test takes the first 84 bytes
of the server's first response in
captures/013-loopback-subscribe-scalars/tcp-stream-__1_49704-to-__1_55690.bin
(real BindAck observed against local AVEVA), decodes the shape
(secondary address "49704\0", n_results=2, NDR transfer syntax accepted,
DCOM negotiate_ack reason=3), then re-encodes and asserts byte-identical
to the original frame. Stronger evidence of wire parity than the prior
synthetic-frame tests, and lets the rest of the M2 stack reason about
the negotiated transfer syntax instead of relying on request-side
context to infer it.

Closes F4 and F5 in design/followups.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-05 21:44:54 -04:00
..

design/ — Rust port architectural plan

This folder is the design contract for the Rust replacement of AVEVA/Wonderware MXAccess. It is the gap between the .NET reference in src/ and the Rust crates that will be written under a sibling rust/ workspace (per CLAUDE.md).

The folder is structured as a small set of focused documents. Read in order; each builds on the previous.

File Purpose
00-overview.md Mission, two-layer goal, architectural principles, non-goals
10-raw-layer.md Byte-accurate raw MXAccess layer (codec + transport + session)
20-async-layer.md Idiomatic Tokio async layer on top of the raw layer
30-crate-topology.md Cargo workspace, crates, dependencies, build/test commands
40-protocol-invariants.md Bill of materials: IIDs, opnums, envelope/handle bytes
50-error-model.md MxStatus, error types, panic/cancellation policy
60-roadmap.md Milestones M0..M6, validation strategy
70-risks-and-open-questions.md Parity gaps, unproven flows, cross-platform constraints
dependencies.md Cross- and within-milestone parallelism map; agent budget per phase
review.md Adversarial review log (BLOCKER/MAJOR/MINOR/NIT findings, all resolved)
prompt.md /loop driver prompt for autonomous M2M6 execution
followups.md Open / resolved deferred work items; auto-triaged by prompt.md Step 0 (created on first /loop run if missing)

The design is grounded in the .NET reference at src/ and the protocol artifacts in docs/, analysis/, and captures/. Do not introduce protocol behavior in these documents that is not already proven in the reference. When adding a new claim about wire format, cite either:

  • a .cs file path in src/MxNativeCodec/, src/MxNativeClient/, or src/MxAsbClient/, or
  • a docs/*.md spec file, or
  • a captures/0NN-frida-* directory or analysis/frida/*.tsv row.

This folder is documentation, not code. When the Rust workspace is created, the design here is the contract it must satisfy. When evidence in captures/ invalidates a design decision here, update the design first, then the code.

Reading order

  • New contributor: 00 → 30 → 10 → 40 → 20 → 50 → 60 → 70.
  • Protocol question: 40 first, then the relevant section of 10.
  • API question: 20 first, then 50.
  • Planning a milestone: 60 first, cross-reference 70 for blockers.
  • Scheduling concurrent work: dependencies.md for the per-phase parallelism map.
  • Driving M2M6 autonomously via /loop: prompt.md (and the followups.md triage log it maintains).