Claude (auto-RE)
398e8ae0af
The whole retail save is 545 bytes: a GDHA container wrapping a zlib payload,
which is a chunk stream — 'GDAA', a length-prefixed game-phase name (GP_BUNK,
one of the title's GP_* screen ids), a 'GHAD' 122-byte progress block, a
count-prefixed table of 16 20-byte save slots, and a trailer.
None of it is guessed. The layout comes from the serializer at 0x822C00E8 and
its callee 0x822BF678: the writer primitive is 0x821885A8(stream, buf, len), the
slot count 16 and the 20-byte stride are literals, and the GHAD block is ten u32,
a u64, four u32, a raw 4-byte field and a raw 54-byte blob = 122 bytes, which is
exactly what the file carries. savegame.py re-serializes the parse and asserts
byte-identity.
Because the struct is written field-by-field with no packing changes, a payload
offset is also the offset in the live save object -- save+8 for GHAD, save+136
for the slot table, and 136+16*20 = 456 is the serializer's very next access.
Confirmed independently: slot 0's trailing two u32 decode as a FILETIME to
2026-07-23 20:07:23 UTC, and the content header's display string (written by the
game) says 07/23/2026 21:08 at UTC+1; the 15 empty slots hold 2006-01-01 rather
than zero.
Field meanings are left ❔ on purpose -- the naming oracle is a diff of two
saves, and all four copies on disk are byte-identical, so a second save has to
be made first. Nothing has been written back to any save.
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Older variant: wait for the title (green Ⓐ glyph at px 625,618) and tap A. Superseded by skip_intro.sh.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.