cbf52ba9f9
Closes the 4-byte record key. tag_hash is name_hash's shape -- byte-sum checksum in the top byte over a 24-bit modular polynomial -- with two different constants: modulus 0x00FFFFDF (2^24-33, prime) instead of 0x00FFF9D7, and no lowercasing, so tags are case-sensitive. name_hash explains 0 of 8643. Recovered from the tables rather than the executable: every inline field name is a known (name -> tag) pair, and comparing names differing in one character gives the per-position weights 1, 0x100, 0x10000, 0x21, 0x2100, ... -- a byte leaving bit 24 re-enters as 33, i.e. reduction mod 2^24-33. Holds where it is easy to get wrong (distance 8 and 9 carry correctly). A record's key is the tag of its own name: FormationSet rosters 362/362, UnitGroup rosters 281/281, S02 squadron names 111/111 -- so records can be addressed by name without reading the roster first. Implemented in Python (unitgroup.tag_hash) and Rust (sylpheed_formats::hash::tag_hash) with 3 new unit tests carrying disc-derived vectors; cargo test -p sylpheed-formats --lib hash is 8/8 green. Not settled: the guest routine is unlocated, so this uses exact modular arithmetic where the game may use a Barrett step without final fixup.
Runtime-capture harness (sylph-re container)
Screenshot-driven scripts for reading the running retail game's menus under Xenia
Canary + lavapipe, headless. They assume the container helpers screenshot,
vgamepad, pad are on $PATH and HOME=/sylph-home/re.
| Script | What it does |
|---|---|
skip_intro.sh |
Boot → main menu, unattended. Taps A only while the intro movie is actually playing (frame-to-frame RMSE), then once at the PRESS Ⓐ BUTTON title. Static logo screens are left alone, so a stray tap can never land on NEW GAME. |
wait_title.sh |
Older variant: wait for the title (green Ⓐ glyph at px 625,618) and tap A. Superseded by skip_intro.sh. |
step.sh |
One Arsenal navigation step (down/up/next/prev/none) + a compact capture: weapon list stacked over the DATA SHEET. |
sweep.sh |
Walk a whole weapon-type list, capturing only rows that show a DATA SHEET — locked rows (a "Conditions to Develop" panel) are detected by the brightness of the Range Class label box and skipped. |
type.sh |
Change weapon-type tab N times (RB) and report the header strip. |
hp.sh / cyc.sh |
Hangar hard-point carousel: cyc.sh steps it (d-pad down, not left/right) and captures the Name + DATA SHEET. |
Input timing under lavapipe: the game polls input at its own low frame rate, so a 60 ms d-pad tap is dropped roughly half the time. 200 ms is reliable; 300 ms starts to auto-repeat (two rows per press).
Findings produced with these: docs/re/weapon-datasheet-runtime.md.
Guest-memory tools (no screenshots)
| Script | What it does |
|---|---|
gmem.py |
Read the live guest address space out of /dev/shm/xenia_memory_* (Xenia's backing file), addressed by guest VA. find / read / words. |
weapon_runtime.py |
Solve the Weapon/Shell struct layouts against the disc records and read the fields the disc defaults. |
unit_discover.py |
Find which runtime class carries a set of ID strings, assuming no vtable: tallies the word at pointer_site - k across distinct IDs. |
unit_runtime.py |
Same solver for the unit\UN_*.tbl definition objects (vtable 0x820af844). Unions several snapshots — unit definitions are per-stage. |
schema_order.py |
Merge a sub-record's field-declaration order across all tables (topological sort); the layout check that pins fields no table ever values. |
order_check.py |
Test offset = base + 4*index for one table's sub-record against solver output. |
grab_tutorial.sh |
Cold-boot Canary, walk to the Nth TUTORIAL entry, wait for the stage load, snapshot guest RAM. One emulator per capture — backing out of a loaded mission wedges it. |
Snapshot first — cp --sparse=always /dev/shm/xenia_memory_* snap.bin (~2 s) — and
point $GMEM_FILE at the copy; the running emulator pegs every core under lavapipe.
🔴 pgrep -f / pkill -f match YOUR OWN shell
An agent driving this toolkit runs its commands through a wrapper shell whose command line contains the pattern being searched for. So
pgrep -f 'pilot\.py' # matches the wrapper running this very command
pkill -f 'fly_session|pilot\.py' # kills that wrapper — the script dies mid-way
This has cost four separate mistakes in one session: two scripts killed
mid-execution, and twice a "is it already running?" guard that answered yes
because it had found itself. The [p]ilot bracket trick does not help when
the literal invocation (python3 pilot.py …) also appears on the wrapper's
command line.
What works:
pgrep -x xenia_canary # exact NAME match, no -f
ps -eo pid,args | grep 'python3 pilot.py' | grep -v snapshot-bash
kill -9 <explicit pid> # look it up first, then kill by pid
The snapshot-bash filter is the reliable tell: the wrapper's command line
always contains the shell-snapshot path.
🔴 The emulator does not survive the end of an agent turn
/work/.claude/settings.json defines a Stop hook that kill -9s every
xenia_canary when a turn ends, printing "Stop hook killed N stale xenia
process(es)".
So:
- never launch a run intending to read it in a later turn — it will be dead;
- an experiment has to produce its evidence within the turn that starts it;
- prefer measurements that land in the first minutes of flight.
REMAINING OBsteps4 → 8 → 12inside the first few minutes, which is why a two-pass differential works in one turn while a 25-minute freeze watch does not.
This cost three iterations of investigating a "mysterious external SIGKILL", complete with cgroup and host memory forensics, before the hook was found. When a process dies at a session boundary, check the harness first.