docs: the dynamic-RE state was gone - rebuild it, measured rather than remembered

The baseline binary, the profile, the Stage 02 save and the caches all live
outside both repos and had been wiped, and sylph-doctor reports 'all good'
without them. This is the recipe, verified by driving it to Stage 02 flight
rather than by inspecting files.

Three things worth having found:

* the baseline is an INCREMENTAL build, not a scratch one -- auto/upstream-baseline
  differs from the instrumented branch in 202 files and zero submodule gitlinks,
  so checking it out in the shared tree and rebuilding into the existing build dir
  takes ~9 min at -j4. git worktree prune first; a dead worktree still claims the
  branch.
* the baseline CANNOT make a profile (--create_profile_if_none is one of our 50
  commits) and the Sign In dialog cannot be typed into, so bootstrap the profile
  with the instrumented binary once and run the baseline against it.
* the Xbox content .header is NOT needed -- ContentManager::ListContent falls back
  to the directory name when ReadContentHeaderFile fails, checked in the source.
  The LOAD GAME screen then shows date, difficulty, flight time and clear ratio
  anyway, which proves those come out of savedata itself. No header was fabricated.

Trap paid for once: keep the file name xenia_canary. A copy saved as
xenia_canary.baseline-... survives every pkill -x in the toolkit and holds the
run-canary lockfile while ps -C xenia_canary shows nothing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PMRJjbxLqZtsb5Vb7KunPE
This commit is contained in:
Sylpheed RE agent
2026-08-23 17:15:53 +00:00
parent ab1b8950c7
commit 15166bc1ad

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# The container's dynamic-RE state is not durable — how to rebuild it
**Status: ✅ `CONFIRMED` by rebuilding it** (2026-08-23). Everything the dynamic
side of this corpus runs on — the baseline emulator binary, the Xbox profile, the
Stage 02 save, the shader/code caches — lives outside the two git repos and was
**gone** at the start of this session. None of it is recoverable from a git pull,
and `sylph-doctor` reports "all good" without it, so the first symptom is a boot
that dies instantly with `NO PROFILE on disc`.
This file is the recipe, measured rather than remembered.
## What was missing, and what it blocks
| gone | consequence |
|---|---|
| `/sylph-home/re/pure/xenia-canary` (the `auto/upstream-baseline` worktree) and its build | no baseline binary. The instrumented branch stops at the Stage 02 briefing under 384 crash dumps ([`upstream-baseline.md`](upstream-baseline.md)), so **no in-mission work is possible at all** |
| `~/.local/share/Xenia/` — the whole storage root | no profile, no save, no config, no caches |
`launch_mission.sh` needs all of it: it signs in `$(ls "$XENIA_CONTENT")` and
navigates title → **LOAD GAME → slot 01** → READY ROOM → TAKE OFF.
## 1. The baseline binary — rebuild it *incrementally*, not from scratch
The branch itself survives (`auto/upstream-baseline`, tip `c1b57f93b` = upstream
`a5a18f5c7` + the three file-pad commits + the lost-resume fix). What is gone is
only the checkout and the build.
The cheap move is **not** a new worktree: a fresh build directory means building
all of `third_party` again. Instead check the branch out in the shared
`/work/xenia-canary` and let ninja do an incremental build into the existing
`$XENIA_BUILD_DIR`, because the two branches differ in **202 files and zero
submodule gitlinks**:
```bash
cd /work/xenia-canary && git worktree prune # the dead worktree still claims the branch
git checkout auto/upstream-baseline
build-canary Release # ~9 min at -j4 here, vs a scratch build
```
`git worktree prune` is not optional — without it the checkout fails with
*"'auto/upstream-baseline' is already used by worktree at /sylph-home/re/pure/…"*
for a directory that no longer exists.
**Keep both binaries**, because switching the branch back costs another build:
```
/sylph-home/re/bin/baseline-c1b57f93b/xenia_canary XENIA_BIN=… run-canary
/sylph-home/re/bin/instrumented-a60fe7d11/xenia_canary
```
🔴 **Trap, paid for once here: keep the file name `xenia_canary`.** A copy saved
as `xenia_canary.baseline-…` runs fine and then survives every `pkill -x
xenia_canary` in the toolkit — `-x` matches the whole name. The emulator keeps
the `flock` on `/tmp/xenia-canary.lock`, and the next launch fails with
*"an emulator is already running"* while `ps -C xenia_canary` shows nothing. Put
the variant in a **directory** and leave the file name alone.
**Tell the two apart by what is in them, not by the path**, since `build-canary`
writes both to the same place and [has reported success on a failed
build](upstream-baseline.md):
```bash
strings -a "$BIN" | grep -c log_ui_draws # instrumented: 5 baseline: 0
```
## 2. The profile — bootstrap it with the *instrumented* binary
`--create_profile_if_none` is one of our 50 RE commits (`7dbb24e64`) and is **not
on the baseline branch**; the baseline cannot make a profile, and the Sign In
dialog cannot be driven from a script (an ImGui text field, no synthetic key
events reach it). So make the profile once with the instrumented binary and then
run the baseline against it — the content root is emulator-build independent:
```bash
XENIA_BIN=/sylph-home/re/bin/instrumented-a60fe7d11/xenia_canary \
run-canary --create_profile_if_none=SylphRE
# wait for: ProfileManager: RE bootstrap profile 'SylphRE' -> created
pkill -x xenia_canary
```
XUID is fixed at **`B13EBABEBABEBABE`**, which is what makes it scriptable, and
`launch_mission.sh` picks it up on its own.
## 3. The Stage 02 save — from the repo, and **without** a `.header`
`docs/re/captures/savedata-stage02-5pct.bin` is a complete `GDHA` container
(parses clean: `phase GP_BUNK`, slot 0 used, 2026-07-23 20:07). Drop it in at the
path [`structures/savegame-format.md`](structures/savegame-format.md) records:
```bash
C=~/.local/share/Xenia/content/B13EBABEBABEBABE/535107D4/00000001/game01
mkdir -p "$C" && cp docs/re/captures/savedata-stage02-5pct.bin "$C/savedata"
```
The companion `Headers/00000001/game01.header` is **not** in the repo and is
**not needed** — checked in the source rather than assumed:
`ContentManager::ListContent` (`src/xenia/kernel/xam/content_manager.cc`)
enumerates *directories*, and when `ReadContentHeaderFile` fails it synthesises
the record from the directory name. The slot is listed either way; only the
display string differs (`game01` instead of
`Game01 07/23/2026 21:08 STAGE02 EASY`). So there is no need to fabricate a
328-byte Xbox content header, which would have been a guess with no oracle.
## Verified end to end — and one new trap in the scripted route
The restored state was checked by **driving it**, not by inspecting files:
1. `LOAD GAME` lists the slot (![](captures/loadgame-slot01-headerless-install.png))
as `01 · 07/23/2026 21:08 · EASY · 000:05:24 · 5 %`, with the Details panel
reading `STAGE02 — Declaration of War`, `At Standby`, `4101 P`. Note what that
settles: **every detail on that screen comes out of `savedata`**, not out of
the Xbox content header that was not installed.
2. → READY ROOM → TAKE OFF → launch cinematic → objective card →
**Stage 02 flight** (![](captures/stage02-inflight-restored-state.png)),
`TIME 00:18.01`, `REMAINING OB 004`, hull 1500 / shield 400. `pilot.py` bound
and flew it (`ENGAGE … tgt=e010_ADAN_Attacker_S`), so the whole live-memory
toolchain works against the restored profile.
🔴 **A fresh profile inserts an extra dialog, and it desynchronises
`launch_mission.sh`.** After `LOAD GAME → slot 01 → YES` the title puts up
**"Auto-Save is active. OK?"** (YES preselected) before the READY ROOM. The
launcher's press sequence is fixed and has no slot for it, so every later press
lands one screen early — this run ended up sitting in **OPTIONS → GAME SETTINGS**,
and `wait_flight.sh` correctly reported `NEVER REACHED FLIGHT`. The mission above
was reached by driving the menus by hand from there.
**Checked on the next boot: the dialog does not return** — the auto-save answer
is kept in the profile. The launcher gets further (READY ROOM instead of
OPTIONS) and still misses: it lands on **BRIEFINGS**, i.e. its
`step up; tap A` for TAKE OFF is swallowed by the READY ROOM transition, because
what precedes it is a fixed `sleep 28` rather than a wait for the screen. So
`launch_mission.sh` is **one wait away** from working unattended on restored
state, and both runs here were finished by hand from the screen it stopped on.
That repair is left for whoever needs the launcher, and is noted in
[`BACKLOG.md`](BACKLOG.md); nothing here depends on it.