The SIGHUP/SIGTERM handler gob-encoded the live game tree from the signal
goroutine while the game goroutine was mid-turn mutating it, and AutoSave
removed the save file before encoding — so the failure mode was not a
stale save but a deleted one followed by a possibly torn replacement,
with a window in which the player had neither. The suite has run under
-race since 2026-08-09 and was green because nothing had ever driven the
turn loop concurrently with a signal: evidence of untested, not of safe.
The handler no longer writes anything. AutoSaveOnSignal posts a request,
wakes the input read, and waits up to signalSaveTimeout for the game
goroutine to take it; the encode runs on the goroutine that owns the
state, at the three points where that goroutine can sit: between turns
(command), on waking from a blocked readchar, and while parked in the `!`
shell escape (runShellEscape, which now runs the shell on a helper
goroutine so a hangup during it still rescues the game).
Blocked on input is the case that matters — a dropped connection lands
while the player is thinking, so a flag checked only between turns would
never be looked at. Terminal.ReadChar therefore returns (byte, bool),
with ok false meaning "woken by Interrupt, no key", and term.Tcell posts
a tcell.EventInterrupt onto tcell's own event queue to unpark PollEvent.
readchar services the request and reads again, so no caller sees it.
Running the shell on a helper goroutine would also have moved
term.Tcell.ShellEscape's panic on a failed Screen.Resume onto it, and a
panic at the top of any goroutine terminates the process without running
the deferred calls of the others — including cmd/rogue/main.go's
`defer t.Fini()`. The tty would have been left raw on precisely the path
where the terminal is already broken, which is issue #12's failure on a
path this change created. runShellEscape therefore recovers the helper's
panic and re-raises it on the game goroutine, whose stack has the restore
in it, so "every path restores the terminal via Terminal.Fini before
exiting" stays true.
saveFile writes a temporary file in the save's own directory, fsyncs it
and renames it over the target instead of truncating in place, so a save
that fails — or never happens because the deadline ran out — leaves the
player's previous save whole.
What the handoff guarantees is stated exactly rather than flatteringly:
the encode runs on the state-owning goroutine, so the snapshot is
internally consistent and restorable, but it is not necessarily taken
between commands. Only the check at the top of command is; the other two
service points both sit inside a command call already under way. readchar
is reached from mid-command prompts (--More--, askOverwrite, getStr, the
direction and pack prompts) with the command's mutations already applied,
and runShellEscape is reached from shell, an ordinary '!' command handler
dispatched inside command, with that turn's DoDaemons(Before) and
DoFuses(Before) already fired and its AFTER pass not yet. Restoring
re-enters playit at the top of command, so either way the rest of that
command is lost and a fresh BEFORE pass runs on top of the one in the
snapshot.
The SIGINT/SIGQUIT no-save decision and the single-signal-read ordering
guarantee are untouched. pendingSaver reads the game out from under its
mutex rather than delegating with it held, because the delegated call now
blocks until the save is taken.
The port installed handlers for SIGHUP and SIGTERM only, so SIGINT and
SIGQUIT killed the process with tcell still holding the tty and dropped
the user into a shell with no echo and a scrambled screen. All four
signals now go to one os/signal channel read by one goroutine, and every
path calls Terminal.Fini before os.Exit(0) -- C's leave(), "leave
quickly but curteously" (main.c).
The handlers are installed immediately after term.New(), the call that
raises raw mode, rather than after the game exists. Everything between
those two points ran raw with no handler at all: the save-restore path,
and -d's DeathDemo(), which never returns -- death() blocks in
waitFor('\n') (game/rip.go) -- so a kill -INT during the death demo left
exactly the scrambled terminal this fixes. The game is handed to the
handler afterwards through pendingSaver, whose AutoSave is a no-op until
then: a signal before the game is built restores the terminal and exits
with nothing to save. SIGHUP/SIGTERM autosave on the play path is
unchanged.
The save decision, written into the savesOnSignal comment: SIGHUP and
SIGTERM keep autosaving; SIGINT and SIGQUIT restore and exit without
saving. No path in C saves on INT or QUIT (leave() is endwin-and-exit,
quit() confirms/scores/exits, endit() goes through fatal(), and
save.c auto_save is reserved for HUP/TERM), the semantics agree
(involuntary teardown is worth rescuing a game from; a deliberate "stop
now" must not become a one-keystroke checkpoint against an anti-save-scum
save discipline), and it is the safe choice, since AutoSave gob-encodes
live state the main goroutine is still mutating after removing the old
file.
One reader of one signal is also what closes the corruption window: a
second signal arriving while a SIGHUP's AutoSave is mid-write stays
unread in the buffer instead of exiting out from under the writer.
cmd/rogue/main_test.go pins the membership of handledSignals() itself --
the rest of the file iterates that set, so without that assertion the
suite would pass against a set that had lost SIGINT and SIGQUIT again,
which is the regression this issue exists to prevent -- and covers the
ordering per signal, the save/no-save split (driven from the expectation
table so every entry is read), the mid-save second-signal interleaving,
the pre-game pendingSaver window, and real SIGINT/SIGQUIT/SIGHUP/SIGTERM
delivered to the test process through the same notifySignals wiring the
game uses.
Two premises behind the report were wrong and are recorded rather than
silently fixed: leave() is not installed on SIGINT/SIGQUIT during play
(the wiring is in mdport.c; the shipped build calls md_onsignal_default
and installs nothing, and leave() appears only in the endgame paths of
rip.c and main.c), and Ctrl-C never generated SIGINT here anyway, since
tcell's raw mode clears ISIG and the key arrives as byte 0x03 -- as it
did in C, whose setup() calls curses raw(). The real exposure is
kill -INT / kill -QUIT, a SIGINT to the process group while the ! shell
escape has the screen suspended, and the window after term.New()
described above. Nothing is raw before term.New(), so there was never
anything to cover there.
ARCHITECTURE.md section 9 gains rows for SIGTSTP/tstp() (deliberately
dropped: raw mode means Ctrl-Z cannot reach the process, suspending the
screen from the signal goroutine is a logical race against the drawing
goroutine -- not a data race, since tcell guards Suspend/Resume and Fini
alike -- and C armed tstp only after a successful restore(); the ! shell
escape covers the need), for SIGINT not routing to the interactive
quit() prompt, and for auto_save on the fault signals. Section 5.3's
claim that tcell handles SIGTSTP was false -- tcell registers only
SIGWINCH -- and is corrected, and its "every path restores the terminal"
claim now holds because of the install ordering above.
Part 2 was written as a design sketch before the port was implemented and
refactored, so much of it described the planned code rather than the final
code. Updated the RogueGame/Stats/Object/Flags/Level sketches to the current
names and types (typed ObjectKind, DiceSpec, split o_arm fields, step-1 flag
names, TrapCount, Level list methods); rewrote §4.7 to say the static tables
now live on the per-game gameData struct (no package globals); noted the
daemon and effect handler tables (step 7), the MessageLine extraction (step 6),
the Terminal interface, the flat gob SaveState, and the New(Params) +
os.Exit-on-game-over design (step 8). Added §7.1, a C-name → Go-name rename
table, and a README note about the make targets. Docs only.
One game run is one process, so game-over ends the process directly,
as the C game did with exit(). myExit now restores the terminal
(via the new Terminal.Fini) and calls os.Exit(0); the gameEnd sentinel,
the recover in Run, and the recover in DeathDemo are gone. Run() no
longer returns an error (it does not return — the game exits from
within), and playit's pre-loop setup is split into startLevel/prePlay
so tests can drive a bounded number of turns.
Because death (combat, and starvation over a long session) now exits
the process, the four Run()-to-completion tests can no longer run
through the exit path: TestDeathUnwindsWithGameEnd is removed (it
tested the deleted unwind), the crash-sweep and quit/save session
tests are dropped, and TestRunDownStairs is reworked to drive the
turn loop for a single descend. Score rendering, previously checked
after a scripted quit, is now covered directly by TestScoreRendersList.
Save/restore integrity remains covered by TestSaveRestoreRoundTrip.
NewGame(Config) becomes New(Params), and Restore takes Params too, so
the package's primary type gets the canonical New() constructor with a
named-field Params struct (styleguide points 139, 159). cmd/rogue and
all tests updated; ARCHITECTURE.md constructor references corrected.
Pure rename, suite green.
Adds a minimal Makefile wrapping the toolchain the way sneak's other
repos expose it:
- fmt gofmt -w plus prettier (4-space tabs, proseWrap: always)
- fmt-check fail if any Go or Markdown file is unformatted
- lint golangci-lint run ./...
- test go test ./...
- check fmt-check + lint + test (the local pre-commit gate)
Running make fmt normalizes the four existing Markdown docs to the
shared prettier style (80-column proseWrap: always, aligned tables) —
a one-time reflow with no content change. The repo remains exempt from
the rest of the policy scaffold (no Dockerfile, CI, or REPO_POLICIES).
go.mod, term/ and cmd/ imports, the ARCHITECTURE.md module references,
and the in-game version string. User request; the repo already lives
at this remote.
The port is complete, so the C sources and their build system
(autoconf/automake inputs, Makefiles, Visual Studio project, doc
templates, RPM spec, C build/modernization notes) leave this branch;
they live on in master/modern-rogue for reference.
Also ports the last missing wizard command (things.c pr_list/pr_spec,
the '*' item-probability listing), rewrites README.md for the Go port,
and updates ARCHITECTURE.md's layout notes (game/ has no third-party
imports; tcell lives in term/).
Kept: LICENSE.TXT, rogue.png, rogue.desktop, ARCHITECTURE.md.
Design for the Go port (module sneak.berlin/go/rogue):
- RogueGame instance type owns all former globals; no package globals
- THING union split into Creature (Player/Monster) and Object
- Slices replace THING linked lists; list.c is not ported
- Daemon function pointers become serializable DaemonID enum + dispatch
- tcell/v2 (sole third-party dep) replaces curses; Window cell buffers
preserve the screen-as-data-structure idiom
- encoding/gob snapshot replaces the 2,134-line state.c serializer
- Exact-LCG RNG for seed-compatible dungeon generation, with golden tests
- Per-file porting map, naming conventions, porting order, drop list
Documents the entire Rogue 5.4.4 C codebase ahead of the Go port:
program flow, source file inventory, the full type system (THING
union, PLACE map, rooms, stats, obj_info, daemons), constants and
flag bits, the macro layer, a census of every global variable, and
a function-by-function catalog of all 36 source files.
