A home screen tile is a title of its own (PPSA99170 to PPSA99269) that starts one
game in RetroArch. Titles cannot launch titles (sceSystemServiceLaunchApp returns
0x8094000F from one, sceLncUtilLaunchApp is a null import), so the tile hands a
payload to the console's ELF loader on 127.0.0.1:9021 and exits:
- forwarder/tile.c: the tile's eboot.bin. Reads its title id from
/app0/sce_sys/param.json, stamps it into /app0/launch.elf's slot, sends it to
the loader, logs /app0/tile.log, and leaves through LoadExec("exit") (a return
from main ends in a SIGSYS error notice).
- forwarder/launch.c: the payload. Reads /data/homebrew/<tile>/forward.txt (one
argument a line: --rom, --core, --exit-after-game, src/frontend_mode_ps5.cpp),
waits for the tile to leave, and starts PPSA99169 with those arguments through
sceLncUtilLaunchApp (sceSystemServiceLaunchApp as the fallback).
- tools/build-forwarder.sh builds both; tools/build-title.sh puts them in
dist/PPSA99169/forwarder/ and counts them in the title's identity; the notices
cover both files.
Evidence:
- host: python3 -m unittest tests.test_forwarder (the tile stamps and sends the
payload byte for byte, refuses a lowercase id, a missing or a doubled slot; the
payload passes the five arguments, falls back to SystemService, and an
unstamped payload starts nothing) - OK.
- console (base PS5, 13.40, ShadowMountPlus 1.7-beta5fix1), the test tile
PPSA99170 registered through ShadowMountPlus's manual list:
tile.log "tile PPSA99170: launch payload 110832 bytes, 110832 sent to
127.0.0.1:9021 (errno 0)"; launch.log five arguments, sceLncUtilLaunchApp
00002018; RetroArch's trace "forwarder: /app0/content/nes/<game> with
/app0/cores/fceumm_libretro.so, closing after it"; the tile exited cleanly
(no error notice), back to the home screen after the game.
- gates: format, unit (206 tests), build (tile 11,123 B, payload 110,832 B),
integration (206 tests; a first run timed out starting two scraper test
servers under load, both passed alone and on the rerun), evidence - PASS.
