2 Commits

Author SHA1 Message Date
c89e818dbf feat(asset-bridge): the transport, and the 357 wrong pictures it found
Asset Bridge phase 1 (docs/link/v8.md §16). Sidecar half: RunicGateway/link#41.
Docs half: RunicGateway/docs#236.

The transport for protocol 8, plus phase 0's validator promoted into the overlay
and extended to animations — which is where the interesting part is.

## 357 of the 1,144 "decodable" bodies are wrong pictures, on a STOCK client

Phase 0 measured the art path and left the animation half unbuilt. It has the same
defect, and it is worse: `GetAnimation` decodes through
`new MemoryStream(m_StreamBuffer, false)` — the whole shared buffer, not the
`length` bytes just read into it — so a truncated or absent record does not even hit
end-of-stream. It sails on into the previous animation's bytes.

Measured directly, because no count could tell:

| Decode body 320 (`lookup 22638982, length 0`) straight after… | Comes back |
|---|---|
| body 12, the dragon | the dragon, 176x167, identical hash |
| body 34, the wolf | the wolf's dimensions, 35x34 |
| body 400, the human male | the human, 27x63, identical hash |

The catalogue is **787 bodies, not 1,144**. Importing the other 357 would have written
duplicate creature portraits into the site showing whichever body the walk decoded
before them.

The record walk refused **0** real bodies on the stock client — the false-refusal
measurement §4.5 says the boundary depends on.

## And four of the twelve player bodies, not six

§5.2 listed the elf ghosts (607, 608) as decoding. Their index entry is `length 0`;
what came back was the elf female at her exact dimensions, because 606 is what the
walk decoded immediately before. Confirmed the same way — 607 after the dragon is
the dragon. Phase 4's UOP decoder now covers eight ids rather than six.

## What is here

- **`overlay/Scripts/Custom/Bridge/BridgeAssets.cs`** — the plane. Accepts on the Core
  thread, hands off to a dedicated asset worker, returns immediately. Three rules, all
  answering a specific failure:
  - **one slot**, second request answered `bridge.busy` (425). `Emit`'s queue is bounded
    in *lines*, so 10,000 queued 200 KB replies is 2 GB of shard memory; the bound that
    holds is flow control, on the side where the memory is.
  - **byte budgets** (`AssetBatchBytes`, 512 KiB) under the sidecar's new 1 MiB cap. The
    factor of two is load-bearing: a page always admits its first item, so it may
    overshoot by one, and the headroom is what makes that land on the wire.
  - **replies, never events** — no `reqId`, no answer. An uncorrelated frame is an event
    by definition, and §3.1 is why none of this may be one.
- **`PageBuilder`** — one paging envelope (`more`/`cursor`/`cut`) for all five families
  that will page, defined before the first one needs it. `cut` matters: "short page" has
  three meanings and only `end` means finished.
- **`assets.sources`** — stage 1 of the import gate, its first user.
- **`BridgeAssetValidator.cs`** — promoted from `tools/`, plus `ResolveAnimation` (the
  never-sweep-file-types rule as code, with no loop and no fallback),
  `AnimationRecordSane` and the frame walk.
- **`EXTRACTOR_VERSION`**, **`overlay.toml` protocol 7 → 8**, `AssetsEnabled`.

## Hashing had to come off the request path

§6's gate is (size, mtime) first, hash only when those differ. The first call has nothing
cached, so that still means hashing 1.06 GB — inside the sidecar's 10 s reply timeout it
does not fit. So hashes are computed on their own thread (deliberately not the single-slot
worker, which would answer every status poll `bridge.busy` for the whole pass) and the
reply carries `hashing`/`complete`.

Measured on the real rig: first call instant with `sha256: null`, second call **44 ms**
with every hash present.

## Verified on the wire, not just compiled

Real ServUO 57.4 + the real sidecar + the real client. `GET /assets/sources` → 200,
`X-UOLink-Version: 8`, `imaging: {ok: true}`, and §4.6's diagnostic firing on a live
client: `artDataFile: artlegacymul.uop`, with `art.mul` and `artidx.mul` both carrying
`shadowedBy`. Live events kept flowing through the new capped reader with no warnings.

Not exercised live: the disabled-plane 403 and the busy 425 (both unit-tested on the
sidecar side; the shard halves are a config read and a lock).

- [x] AI-assisted — Claude Code (Opus 5)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016wDDVXWMDz82WqE1i969r4
2026-09-10 08:32:18 -05:00
0ce92152a1 feat(asset-bridge): phase 0 spike — the decoders, from inside a live shard
docs/link/v8.md §16 phase 0. §4 chose to CALL ServUO's vendored `Ultima`
rather than reimplement it, on the evidence of a PowerShell probe against a
stock client — neither the process nor the client the extractor will run in.
This runs the same decoders from inside a running ServUO 57.4 against a
client broken in 21 catalogued ways, and it found more than a crash.

Adds, all under tools/ and therefore never deployed:

  * BridgeAssetProbe.cs — the sweep, plus BridgeAssetValidator, a prototype
    of the validate-before-calling response chosen for §4.2's residual risk.
    Runs off the Core thread, snapshots Race.AllRaces on it, and writes the
    id it is ABOUT to touch to a checkpoint file before every call.
  * BridgeMythicCliloc.cs — the §9 Mythic cliloc reader in net48 C#, ported
    from UOFiddler (Beerware) with every file-derived index bounds-checked.
    Phase 2 promotes this into overlay/.
  * patch_client.ps1 — builds the patched client in five tiers. Hashes every
    file it touches in the SOURCE before and after and aborts on a change.
  * an `assetprobe` verb on BridgeRigDriver, so stock and patched can be run
    against one boot rather than two shard processes.

The findings are written up in tools/scaffolding/README.md. The four that
change what phase 1 has to build:

  * FileIndex's UOP constructor ends `MulPath = uopPath`, so artLegacyMUL.uop
    wins outright and art.mul/artidx.mul are never opened on a current
    client. A validator bounding offsets against art.mul is not approximate,
    it is nonsense — the first run refused 34,299 good statics on that
    mistake, and every refusal looked like a real finding.

  * 22,102 WRONG PICTURES on a stock, unmodified client. Empty UOP index
    slots read `lookup 0, length 0`; Seek treats that as a hit, and
    LoadStatic decodes zero bytes into a shared buffer it reuses, only ever
    grows, and fills from a Read whose return value is discarded — so the id
    renders the previously-decoded asset. The mul path does not do this
    (artidx stores -1), which is why the earlier probe counted 32,766 of
    them as "ok". A bulk import that trusted the library would have written
    22,102 duplicate images under ids that have no art.

  * The validator caught all 8 record-level defects — 7 of which the library
    rendered without raising anything, including a verdata lookup past
    verdata.mul's own end (Verdata.Seek is bounds-checked nowhere) and an
    8000x8000 bitmap allocated from two bytes in a file. It refused NOTHING
    across 49,151 statics and 16,384 land tiles on the stock client, which
    is the number that makes the boundary defensible.

  * §4.1's crash reproduces in-process: one Ultima.Gumps.GetGump(2) and the
    ServUO process disappeared — no catch reached, no console line, the
    checkpoint file the only record. "Nothing calls Ultima.Gumps" is now an
    earned safety rule.

§9 is proven: 123,490 entries in 218 ms, byte-identical to UOFiddler's own
output, with no UOFiddler installed and nothing copied to a server.

Not covered, and named as phase 1 work: the animation path has no validator
at all, and the patched wolf decoded something else in silence.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016wDDVXWMDz82WqE1i969r4
2026-09-10 03:05:32 -05:00