fix: restore the terminal on SIGINT/SIGQUIT (closes #12) #23
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Closes #12.
The port installed handlers for SIGHUP and SIGTERM only, so SIGINT and SIGQUIT
killed the process with tcell still holding the tty. All four signals now go to
one
os/signalchannel read by one goroutine incmd/rogue/main.go, and everypath calls
Terminal.Finibeforeos.Exit(0)— C'sleave(), "leave quicklybut curteously".
Reworked at
dfb34beagainst the review off602ecd; see the rework commentfor the point-by-point.
When the handlers are installed
Immediately after
term.New(), the call that raises raw mode — not after thegame is built. Everything between those two points ran raw with no handler at
all: the save-restore path, and
-d'sg.DeathDemo(), which never returns(
death()blocks ing.waitFor('\n'),game/rip.go). Akill -INTduring thedeath demo therefore still left the scrambled terminal this PR is about.
The game is handed to the handler afterwards through
pendingSaver, whoseAutoSaveis a no-op until then: a signal arriving before the game existsrestores the terminal and exits with nothing to save. SIGHUP/SIGTERM autosave on
the play path is unchanged. The death demo is deliberately left without a saver —
a throwaway demo game must not overwrite the player's save file.
The decision: SIGINT/SIGQUIT do NOT save
Documented in full on
savesOnSignalincmd/rogue/main.go. SIGHUP and SIGTERMkeep autosaving; SIGINT and SIGQUIT restore the terminal and exit without
saving. Three grounds:
leave()is endwin andexit (it explicitly throws away pending output),
quit()confirms, scores andexits,
endit()goes throughfatal(), andsave.c auto_saveis reserved forHUP/TERM. Saving on HUP/TERM but not on INT/QUIT is exactly C's split.
machine is going down — so rescuing the game is right. INT/QUIT are the player
deliberately saying "stop now". Rogue scores a deliberate quit and its save
discipline is anti-save-scum by design (restoring consumes the file), so
making Ctrl-C a free checkpoint would turn it into a one-keystroke undo for a
bad turn: a gameplay change, not a robustness fix.
state, and
AutoSaveremoves the save file before gob-encoding that livestate. On HUP/TERM that risk is accepted because the process is dying anyway.
On INT/QUIT there is nothing to rescue, so the port takes the option with no
corruption window at all.
Ordering, and the race the issue warned about
One goroutine reads exactly one signal. A second signal — a SIGINT landing while
a SIGHUP's
AutoSaveis still writing — stays unread in the buffered channeland can never call
os.Exitout from under the writer. Within the handler theorder is:
AutoSave(only if this signal saves), thenTerminal.Fini, thenos.Exit(0)— the same ordermyExituses ingame/rip.go.TestLeaveOnSignalIgnoresLaterSignalsreproduces that exact interleaving.SIGHUP/SIGTERM autosave behavior is unchanged; the save/restore suite is
untouched and green.
Two premises in the issue that turned out to be wrong
Recorded rather than silently fixed, since neither changes the fix. Both were
independently verified against the C sources during review and confirmed:
leave()is not installed on SIGINT/SIGQUIT during play. The wiring isin
mdport.c, notmain.c.md_init()callsmd_onsignal_exit(), thensetup()(mach_dep.c:136) callsmd_onsignal_default()in the shippedbuild — everything back to
SIG_DFL, nothing installed. The variant thatwires SIGHUP/SIGTERM to
auto_saveand SIGINT toquit(),md_onsignal_autosave(), is defined unconditionally inmdport.c; onlyits call site (
mach_dep.c:143-147) is#ifdef DUMP.leave()is installedon SIGINT in exactly two endgame places,
rip.c:237indeath()andmain.c:305insidequit()after the player confirms, as a second-Ctrl-Cescape hatch while the scoreboard prints.
Start()callsgolang.org/x/term.MakeRaw, which clearsISIG, so Ctrl-C arrives asKeyCtrlCandtranslateKeyalready turns it into byte0x03for thecommand loop. C did the same —
setup()calls cursesraw(), which alsoclears
ISIG. The reproducer as written does not fire.The residual exposure, stated correctly:
kill -INT/kill -QUITfromanother terminal, a SIGINT delivered to the process group while the
!shellescape has the screen suspended, and the unarmed window after
term.New()described at the top. Nothing is raw before
term.New(), so there was neveranything to cover there — the earlier revision of this description had that
backwards.
SIGTSTP: deliberately dropped, recorded in ARCHITECTURE.md section 9
Not handled, with the reasoning in the section 9 prose:
ISIGis clear, which is what makesVSUSPlive, soCtrl-Z never reaches the process as a signal — it arrives as byte
0x1a, justas in C. Only an explicit
kill -TSTPcan deliver it, which is not a playeraction.
Screen.Suspend/Resumefrom thesignal goroutine while the game goroutine may be inside
RenderorPollEvent. That is a logical race over screen state, not a data race —tcell guards
Suspend/ResumeandFinialike with the screen mutex, whichis also why the
Finithis PR calls from the signal goroutine is safe. Doingit properly means plumbing the signal through the input loop and handling it
synchronously, a design change well beyond a signal-safety fix.
tstpis armed only bymd_tstpresume(), whichruns after a successful
restore()(save.c:257), so a freshly started Cgame never had a SIGTSTP handler either.
term.Tcell.ShellEscape(the!command) already covers getting to a shelland back, doing the same suspend/resume dance synchronously where it is safe.
Section 9 also gains rows for SIGINT not routing to the interactive
quit()prompt (an async handler cannot re-enter the message/input machinery from
another goroutine;
Qreaches the same prompt from inside the turn loop) andfor
auto_saveon the fault signals (SIGILL/TRAP/FPE/BUS/SEGV/SYS are Goruntime panics, and gob-encoding the state that just faulted would risk
replacing a good save with a corrupt one). Section 5.3's claim that "SIGTSTP/
resume and resize are handled by tcell" was false — tcell registers only
SIGWINCH — and is corrected; its "every path restores the terminal" claim now
holds, because of the install ordering at the top.
Testing, including what could not be tested
cmd/rogue/main_test.go:TestHandledSignalsSet— pins the membership ofhandledSignals()to exactly{SIGHUP, SIGTERM, SIGINT, SIGQUIT}. Every other test iterates that set, so
this is the one that can fail on the actual regression: mutating the set back
to {SIGHUP, SIGTERM} now fails the suite.
TestLeaveOnSignalRestoresTerminalBeforeExit— for every handled signal, theterminal is restored before the process exits, with exit code 0.
TestLeaveOnSignalSaveSplit— pins the decision:save,fini,exitforSIGHUP/SIGTERM,
fini,exitfor SIGINT/SIGQUIT, cross-checked againstsavesOnSignal. Driven from the expectation table rather than fromhandledSignals(), so every entry is actually read.TestLeaveOnSignalIgnoresLaterSignals— a saver that queues a second signalmid-save, proving the second one is never read and cannot truncate the write.
TestPendingSaverArmsBeforeTheGameExists— a signal arriving before the gameis built restores the terminal and exits without saving; once the game is
handed over, the same saver writes it.
TestLeaveOnRealSignal— delivers real SIGINT, SIGQUIT, SIGHUP and SIGTERM tothe test process through the same
notifySignalswiring the game uses, andasserts the full expected step sequence per signal, including the save split.
What could not be tested headlessly: that the tty actually leaves raw mode.
That needs a controlling terminal and a live tcell screen, which a headless test
run does not have, so the tests stop at the
Terminal.Finicall.term.Tcell.Finiis a one-line pass-through to tcell'sScreen.Fini, the samecall
myExit(game/rip.go) already depends on for every normal game exit, sothe untested remainder is the same code path a death or a
Qalready exercisesin real play. Stating this rather than skipping it silently, per the issue's
definition of done.
One deviation from the usual test-file convention: this file carries no
//nolint:testpackageheader.testpackageexemptspackage main, sonolintlintrejects the directive as unused; a comment under the package clauseexplains why it is absent.
Verification
make fmt(Go and Markdown), thenmake checkgreen:fmt-check+lint(0 issues) +
test. Because golangci-lint on this host shares one cacheacross concurrent sessions, every lint and check run was made in a retry loop
and only accepted when it neither reported
parallel golangci-lint is runningnor mentioned any path outside this worktree;
make checkwas accepted greentwice under that guard.
make testcarries-timeout 30s -race -cover. The signal tests arerace-detector clean, including the handler goroutine, the
pendingSaverhandoff, and the real-signal delivery test — no suppression needed anywhere.
handledSignals()temporarily reduced to{SIGHUP, SIGTERM},
make testfails onTestHandledSignalsSetandTestLeaveOnSignalSaveSplit. Restored afterwards..golangci.ymluntouched (sha256021cc83f...46bcb); nogame/testdata/golden regenerated.
What changed
One commit, four files,
+402/-12.cmd/rogue/main.go—installAutosavebecameinstallSignalHandlers,covering SIGHUP, SIGTERM, SIGINT and SIGQUIT through a single
os/signalchannel read by a single goroutine (
notifySignals+leaveOnSignal). Thehandler body is split behind two tiny interfaces (
saver,finisher) and aninjected
exit func(int)so it can be driven headlessly.savesOnSignalcarriesthe decision comment.
cmd/rogue/main_test.go(new) — four tests, described under Verification.ARCHITECTURE.md— section 9 gains three rows plus prose; section 5.3'ssignal paragraph rewritten.
TODO.md— Completed Steps entry in the same commit.Next StepNOTrotated, per the ratified precedent that out-of-band issue work leaves it alone.
The save-vs-no-save decision, and why
SIGHUP/SIGTERM save. SIGINT/SIGQUIT restore the terminal and exit without
saving. Written into the
savesOnSignaldoc comment incmd/rogue/main.go,not just here. Three independent grounds, all pointing the same way:
leave()is endwinand exit and explicitly throws away pending output;
quit()confirms, printsthe score and exits;
endit()goes throughfatal()to endwin and exit.save.c auto_saveis used for HUP/TERM and nothing else. Keeping HUP/TERMsaving while INT/QUIT do not reproduces C's split exactly — the port's
existing autosave handlers were already the C-faithful half of it.
involuntary teardown — the connection dropped, the machine is going down — and
rescuing the player's game is the kind thing to do. INT and QUIT are the
player deliberately saying "stop now". Rogue scores a deliberate quit, and its
save discipline is anti-save-scum by construction (restoring consumes the
file), so turning Ctrl-C into a free checkpoint would make it a one-keystroke
undo for a bad turn. That is a gameplay change dressed up as a robustness fix,
and it is not what this issue asked for.
main goroutine is mid-turn mutating game state, and
AutoSaveremoves thesave file before gob-encoding that live state. On HUP/TERM that risk is
accepted because the process is about to die anyway and a best-effort save
beats none — that is the pre-existing, deliberate behavior and it is
untouched. On INT/QUIT there is nothing to rescue, so the port takes the
option with no corruption window at all.
Ordering, explicitly
The issue warned against a handler that can race
os.Exitinto a corrupt save.The design that closes it: one goroutine reads exactly one signal. A SIGINT
landing while a SIGHUP-triggered
AutoSaveis mid-write stays unread in thebuffered channel and can never call
exitout from under the writer. Within thehandler the order is
AutoSave(only whensavesOnSignal), thenTerminal.Fini, thenos.Exit(0)— the same ordermyExituses ingame/rip.go.TestLeaveOnSignalIgnoresLaterSignalsbuilds that exactinterleaving with a saver that queues a second signal from inside the save and
asserts it is never consumed.
The trade-off worth naming: dropping the second signal also means a second
Ctrl-C cannot force-exit if an autosave hung. C had
leave()as that escapehatch during scoring. An
AutoSaveis a local gob write with no network or lockinvolved, so the exposure is a stuck local filesystem, and the alternative is the
save-corruption window the issue explicitly forbids. Calling it out rather than
leaving it implicit.
Two premises in the issue that did not hold
Neither changes the fix; both are recorded in
ARCHITECTURE.mdand the commitmessage rather than quietly worked around.
leave()is not installed on SIGINT/SIGQUIT during play. The wiring is inmdport.c, notmain.c:332.md_init()callsmd_onsignal_exit(), thensetup()(mach_dep.c:136) callsmd_onsignal_default()in the shippedbuild — every handler back to
SIG_DFL, nothing installed at all. The variantthat wires SIGHUP/SIGTERM to
auto_saveand SIGINT toquit(),md_onsignal_autosave(), is compiled in only under#ifdef DUMP.leave()is installed on SIGINT in exactly two endgame spots —
rip.c:237indeath()and
main.c:305insidequit()once the player has confirmed — as asecond-Ctrl-C escape hatch while the scoreboard prints. So "match C exactly"
could not settle the save question on its own; the decision above had to be
made on the merits.
tty
Start()callsgolang.org/x/term.MakeRaw, which clearsISIG, soCtrl-C arrives as
KeyCtrlCandterm/tcell.go translateKeyalready turns itinto byte
0x03for the command loop. C behaves identically —setup()callscurses
raw(), which also clearsISIG. The "press Ctrl-C, land in ascrambled shell" reproducer does not fire as written. The real exposure that
this PR fixes is
kill -INT/kill -QUITfrom another terminal, plus thewindow before
term.New()returns.SIGTSTP
Recorded in ARCHITECTURE.md section 9 as deliberately dropped, with reasoning,
rather than handled:
raw mode clears
ISIG, which is what makesVSUSPlive — so it arrives asbyte
0x1a. Only an explicitkill -TSTPcan deliver it, which is not aplayer action.
Screen.Suspend/Resumefrom the signalgoroutine while the game goroutine may be inside
RenderorPollEvent,which is exactly the race this issue forbids introducing. A correct port has to
plumb the signal through the input loop and handle it synchronously — a design
change beyond a signal-safety fix, and out of scope by the tracker rule.
tstpis armed only bymd_tstpresume(), called fromsave.c:257after a successfulrestore(), soa freshly started C game never had a SIGTSTP handler either.
term.Tcell.ShellEscape(the!command) already does the same suspend/resumedance synchronously on the game goroutine, where it is safe, and covers the
"get me to a shell" need.
Section 9 also gained a row for SIGINT not routing to the interactive
quit()prompt (an async handler cannot re-enter the message and input machinery from
another goroutine;
Qreaches the same prompt from inside the turn loop) and onefor
auto_saveon the fault signals SIGILL/TRAP/FPE/BUS/SEGV/SYS (Go runtimepanics; gob-encoding the state that just faulted would risk replacing a good save
with a corrupt one).
While there, section 5.3's claim that "SIGTSTP/resume and resize are handled by
tcell" was simply false — tcell registers only SIGWINCH — and is corrected. That
stale line is plausibly why SIGTSTP looked handled and never got listed.
How I verified it
make fmtthenmake check—fmt-check,lint(0 issues),test— allgreen.
make testcarries-timeout 30s -race -cover. Run repeatedly, cleanevery time; no new races, nothing suppressed, no
//nolintadded.TestLeaveOnSignalRestoresTerminalBeforeExit— for every handled signal, theterminal is restored before the process exits, exit code 0. The issue's core
claim, asserted on step ordering rather than on a mock call count.
TestLeaveOnSignalSaveSplit— pins the decision as an executable spec:save,fini,exitfor SIGHUP/SIGTERM,fini,exitfor SIGINT/SIGQUIT,cross-checked against
savesOnSignalso the table and the predicate cannotdrift apart.
TestLeaveOnSignalIgnoresLaterSignals— the mid-save second-signalinterleaving described above.
TestLeaveOnRealSignal— sends real SIGINT, SIGQUIT, SIGHUP and SIGTERM to thetest process and routes them through the same
notifySignalswiring the gameinstalls, confirming the plumbing works end to end and not just the handler in
isolation.
.golangci.ymluntouched; nogame/testdata/golden regenerated;c-masterand
modern-rogueonly ever read viagit show.What could not be verified headlessly, stated rather than skipped: that the
tty actually comes back out of raw mode. That needs a controlling terminal and a
live tcell screen, which a headless run does not have, so the tests stop at the
Terminal.Finicall.term.Tcell.Finiis a one-line pass-through to tcell'sScreen.Fini— the same callmyExitalready relies on for every normal exit,so the untested remainder is a code path each death and each
Qquit alreadyexercises in real play.
One convention deviation to flag for review:
cmd/rogue/main_test.gocarries no//nolint:testpackageheader, unlike thegamepackage's test files.testpackageexemptspackage main, sonolintlintrejects the directive asunused and
make lintfails with it present. A comment under the package clausesays so.
Review of PR #23 (head
f602ecd) — VERDICT: FAIL /needs-reworkReviewed against issue #12, its comment thread,
TODO.md,MEMORY.md,README.md,ARCHITECTURE.mdsections 5.3 and 9, and the C reference read viagit show origin/c-master:. Verified in a throwaway worktree atf602ecd; theshared clone was left on
main, clean.Blocking findings
B1.
make checkis red.make lintreports 1 issue; the PR claims 0.Deterministic across two runs,
golangci-lint 2.12.2. This is not alinter-version artifact: the base commit
4aa4bablints 0 issues with theidentical binary and identical
.golangci.yml. The literal"exit"occurs 5times (
main_test.go:48, 88, 110, 111, 112, 113, 154),"save"and"fini"similarly;
goconstis on because.golangci.ymlsetsdefault: allwith noexclusion presets.
Why it matters:
MEMORY.md:32-35is an iron rule — "the whole golangci-lint runis 0 issues, so keep it that way — decompose new hot spots rather than reaching
for a nolint." Issue #12 DoD 6 requires
make checkfully green. And the PRbody, the PR comment, and
TODO.mdall state "lint (0 issues)" and "make checkfully green"; that verification claim is false as submitted.Acceptable: hoist
save/fini/exitinto file-level constants and use themin the recorder and the expectation tables. Per
MEMORY.md, a//nolint:goconstis not the acceptable fix here.
B2. The tests are vacuous for the exact regression issue #12 exists to prevent.
All four tests iterate
for _, sig := range handledSignals()(
main_test.go:82, 116, 194). Nothing anywhere asserts whathandledSignals()actually contains. Mutation-proved:
cmd/rogue/main.go:122-126toreturn []os.Signal{syscall.SIGHUP, syscall.SIGTERM}— i.e. reinstate the pre-PR bug in full, SIGINT and SIGQUITonce again killing the process with the tty raw — and the suite is green:
ok git.eeqj.de/sneak/rgoue/cmd/rogue. Zero failures.TestLeaveOnSignalSaveSpliteven declares awantmap keyed on all four signals(
main_test.go:109-114) but drives the loop fromhandledSignals(), so theSIGINTandSIGQUITentries are never read. The suite is self-referential: ittests that the handler behaves consistently with whatever set it is given, not
that the set is right.
For contrast, the mutations that are caught: deleting
t.Fini()fromleaveOnSignal(main.go:198) fails all four tests; forcingsavesOnSignaltoreturn truefailsTestLeaveOnSignalSaveSplitoninterruptandquit. So the handler body is well covered — the signal set,which is the entire subject of the issue, is not.
Acceptable: assert the contents of
handledSignals()directly against anexplicit expected set, or drive the tests from the
wantmap keys and requireeach key to be present in
handledSignals().B3. Handlers are installed too late;
rogue -dis left completely unprotected, so DoD 1 is unmet on that path.cmd/rogue/main.go:42term.New()puts the tty in raw mode. Handlers are notinstalled until
cmd/rogue/main.go:72. Everything in between runs raw with nohandler at all:
main.go:56game.Restore(args[0], params)— file I/O.main.go:66-70g.DeathDemo(), which never returns. It reachesgame/rip.go:60-70death(), which callsg.score(...)and theng.waitFor('\n')— an indefinite block on the player pressing return,with the terminal raw and SIGINT/SIGQUIT/SIGHUP/SIGTERM all at their default
dispositions.
A
kill -INTduringrogue -dtherefore still leaves precisely the scrambled,echo-less terminal that issue #12 is about. DoD 1 ("SIGINT (and SIGQUIT) restore
the terminal before the process exits") is not satisfied on that path, and
ARCHITECTURE.mdsection 5.3's new sentence "Every path restores the terminalvia
Terminal.Finibefore exiting" is not true as written.Acceptable: install immediately after
term.New()/defer t.Fini()(
main.go:48), ahead of the restore and demo branches. The saver can be wired inlater or the handler given a nil-tolerant saver; the terminal restore is the part
that must be armed the instant the tty goes raw.
B4. The stated exposure analysis is wrong in the commit message, the PR body, and
TODO.md.All three assert the remaining exposure is "
kill -INT/kill -QUIT… plus thewindow before
term.New(), which this fix covers". Nothing is raw beforeterm.New(), so there is nothing there to restore and nothing to cover; theactual raw-mode window is after
term.New()and is exactly the one leftuncovered by B3. Since this text is landing in
TODO.mdand the commit messageas a durable record, it needs to be corrected, not just softened.
Highest-priority task: both disputed premises verified
Both of the implementer's corrections are CORRECT. I checked them against the
C sources and the Go/tcell code rather than taking either side on faith.
(a)
leave()is not installed on SIGINT/SIGQUIT during play — CONFIRMEDmd_init()(mdport.c:133-137):#if defined(DUMP)→md_onsignal_default(),#else→md_onsignal_exit(). Shipped (non-DUMP) build takesmd_onsignal_exit().setup()(mach_dep.c:137, lines 143-147):#ifdef DUMP→md_onsignal_autosave(),#else→md_onsignal_default(). Shipped buildtakes
md_onsignal_default().md_onsignal_default()(mdport.c:141-176) sets HUP, QUIT, ILL, TRAP, IOT,EMT, FPE, BUS, SEGV, SYS, TERM to
SIG_DFLand never touches SIGINT.So during play in the shipped build SIGINT and SIGQUIT are both
SIG_DFL—no handler, no
endwin(), terminal not restored.md_onsignal_autosave()(mdport.c:217-255) is the only thing wiringHUP/TERM →
auto_save, QUIT →endit, INT →quit. Its only call sitein the tree is
mach_dep.c:144, inside#ifdef DUMP(
extern.h:193is the prototype;mdport.c:217the definition).signal(SIGINT, leave)appears exactly twice:main.c:305(insidequit(),after the player answers
y) andrip.c:237(insidedeath(), right aftersignal(SIGINT, SIG_IGN)atrip.c:235). Both endgame, both asecond-Ctrl-C escape while the scoreboard prints.
main.c:332is the definition ofleave(), not an installation of it.Issue #12's premise "C
main.c:332installsleave(int sig)… on SIGINT andSIGQUIT" is factually wrong. The PR's correction stands. Also verified the
code comment's supporting claim:
endit()(main.c:161-165) →fatal()(
main.c:172-179) →endwin()+my_exit(0), no save. Accurate.(b) Ctrl-C never generated SIGINT here — CONFIRMED, and issue #12's severity was overstated
devTty.Startcallsterm.MakeRaw(tty.fd)(
tty_unix.go:83; same atstdin_unix.go:83).golang.org/x/termv0.37.0term_unix.go:34:termios.Lflag &^= unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN—ISIGis cleared.term/tcell.go:169(namedKey,reached from
translateKeyatterm/tcell.go:101) already returns'\x03'.setup()calls cursesraw()atmach_dep.c:154, which alsoclears
ISIG.Stated plainly, as requested: the user-facing severity claimed in issue #12 was
overstated. The headline reproducer — "pressing Ctrl-C kills the process with
tcell still holding the terminal in raw mode … needing a blind
reset" — doesnot fire, and the assertion that Ctrl-C is "the most reachable robustness gap in
the port" does not hold. The genuine residual exposure is
kill -INT/kill -QUITfrom another terminal; a SIGINT delivered to the foreground processgroup while the
!shell escape has the screen suspended(
term/tcell.goShellEscape, whereSuspend()has restored cooked mode);and the unarmed window of B3. The fix is still worth having — it is just
robustness hardening, not the top-severity player-facing bug the issue described.
Other verification results
Ordering / corruption window (item 1) — sound as claimed.
notifySignals(
main.go:175-183) creates one buffer-1 channel;installSignalHandlers(
main.go:168-170) starts exactly one goroutine;leaveOnSignal(
main.go:193-200) performs exactly one receive and never loops. A secondsignal arriving mid-
AutoSavesits unread. I could not construct aninterleaving where a second signal exits out from under the writer. The
residual window that remains is the main goroutine's own
myExit()(game/rip.go:17-20) callingos.Exit(0)while a HUP-triggeredAutoSaveis mid-encode — but that is byte-for-byte the pre-PR behavior, it isnot what the PR claims to have closed, and the claims as written are correctly
scoped to "a second signal". Net effect on this axis is an improvement: pre-PR,
a SIGINT during a HUP autosave killed the process outright at
SIG_DFL.SIGHUP/SIGTERM autosave unchanged (item 2) — confirmed. The diff touches 4
files, none under
game/.savesOnSignalreturns true for exactly HUP and TERM,AutoSaveis invoked identically, and the save/restore suite passes.Decision documented in code (item 3) — satisfied.
cmd/rogue/main.go:128-159carries the full reasoning on
savesOnSignal, not only in the PR body. Contentchecked against C and accurate (one wording nit at M2 below).
Non-vacuity (item 4) — partly satisfied. Handler body well covered; signal
set not covered at all. See B2.
Convention deviation, missing
//nolint:testpackage(item 5) — the reasoningis CORRECT, not a defect. Reproduced: adding
//nolint:testpackage // white-box tests reach unexported stateabovepackage mainyieldsThe explanatory comment is present at
cmd/rogue/main_test.go:3-5. Accept as-is.tcell signal registration (item 6) — confirmed. tcell v2.13.10 calls
signal.Notify(tty.sig, syscall.SIGWINCH)attty_unix.go:108andstdin_unix.go:108, and registers nothing else. The old section 5.3 claim that"SIGTSTP/resume and resize are handled by tcell" was indeed false; the correction
is right.
Pre-existing AutoSave race (item 7) — correctly left alone. Not touched, not
made worse, not "fixed" as scope creep.
Minor findings (non-blocking, fix while reworking)
ARCHITECTURE.mdsection 9, SIGTSTP prose: "callingScreen.Suspend/Resumefrom the signal goroutine while the game goroutinemay be inside
RenderorPollEvent— a data race". This proves too much:the code shipped in this very PR calls
Screen.Finifrom the signal goroutinein exactly that situation (
cmd/rogue/main.go:198). In tcell both aremutex/
finiOnce-guarded (tscreen.go:369-376forFini,tscreen.go:1145-1152plusengage/disengageforSuspend/Resume), soneither is a Go data race. The real SIGTSTP objection is a logical
screen-state race, and the doc should say that instead.
cmd/rogue/main.go:139-141: "(md_onsignal_autosave, mdport.c,compiled only under DUMP)".
md_onsignal_autosave()is definedunconditionally at
mdport.c:216-255; only its call site(
mach_dep.c:143-147) is#ifdef DUMP. Substance correct, wording not.ARCHITECTURE.mdsection 5.3: "Every path restores the terminal viaTerminal.Finibefore exiting" — untrue on the-dpath; see B3.TestLeaveOnRealSignal(main_test.go:213-215) asserts onlystrings.HasSuffix(..., "fini,exit")plus exit code, so the end-to-end testnever checks the save/no-save split it is best placed to check. Covered
elsewhere, so not blocking, but the strongest test carries the weakest
assertion.
separately:
chooseSeed(cmd/rogue/main.go:204-210) silently ignores aset-but-unparseable
SEEDand falls back to time+pid. Set-but-unparseableconfig must fail loudly. Not introduced here; do not fix in this PR.
Standard gate
make checkgreen from a clean worktreelintfails, see B1make test(-timeout 30s -race -cover), 3 runs,GOFLAGS=-count=1-race.golangci.ymlsha256021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb, not in diffscript/addedgame/testdata/goldens regenerated(closes #12)TODO.mdCompleted Steps entry added,Next Stepnot rotatedTODO.mdhunkt.Parallel()where applicablemain4aa4bab.gitea/or.github/); Gitea reports 0 statuses. Not aneeds-checkscaseVerdict
FAIL —
needs-rework. Four blocking items: B1 (lint red, contradicting anexplicit "0 issues" claim, against the
MEMORY.mdzero-issues rule and DoD 6),B2 (the test suite passes with SIGINT/SIGQUIT removed from
handledSignals()—the regression the issue exists to prevent is unguarded), B3 (
rogue -drunsraw with no handlers, so DoD 1 is unmet there), B4 (the exposure analysis
recorded in the commit message, PR body and
TODO.mdis wrong about whichwindow the fix covers). Plus M1-M4.
The core design is right and the two disputed premises are both correct — the
C-source and tcell/
x/termanalysis holds up under independent checking, andissue #12 was wrong on both counts, with its stated severity overstated.
savesOnSignalis well argued and properly documented in code. The rework isbounded: constants for the step strings, an assertion pinning
handledSignals(), moving the install to just afterterm.New(), and correctingthe three prose claims.
Manager notes (the review is in its own comment above).
Verdict accepted: FAIL. Labeling
needs-rework.I independently re-measured B1 before accepting it, and it is real. On a
clean golangci-lint cache with no concurrent run,
origin/main(4aa4bab)lints 0 issues, and
origin/sig-leavelints exactly:So the PR's claim of "lint 0 issues / make check fully green" was false, and
MEMORY.md's zero-issues rule is violated. That is blocking on its own.But getting that measurement surfaced a real environment problem, and it
partly exculpates the implementer. My first three attempts to reproduce were
garbage:
make lintreported 399 issues (mnd: 285,nolintlint: 64, …) againstfile paths under
/tmp/rev23/— a worktree that no longer existed.golangci-lint was serving cached results for deleted directories.
Error: parallel golangci-lint is running.The cause: golangci-lint keeps one cache at
~/.cache/golangci-lint, andthere are ~18 concurrent repo-manager sessions on this host all invoking it
from throwaway worktrees under
/tmp. They share that cache and its lock.A run can therefore return another repo's stale findings, or refuse to run at
all. A green lint result from any agent on this host is not trustworthy
unless the cache was clean and no other run was in flight.
That is very likely how the implementer saw green while the reviewer saw red —
neither was lying. It does not excuse the outcome (the branch is red), but
it means "the author fabricated a green run" is the wrong conclusion.
Practical consequence for the rework: verify
make lintin a retry loopuntil you get a run that does not say
parallel golangci-lint is running, andtreat any result mentioning paths outside your own worktree as void and re-run.
This also sharpens #4. I argued there that an unpinned linter makes the gate
non-reproducible; the failure mode turns out to be worse than version drift —
the gate is not even reproducible against itself on one machine under
concurrency.
Two premises of issue #12 — both mine — are now CONFIRMED WRONG, verified
against the C sources rather than asserted:
leave()is not installed on SIGINT/SIGQUIT during play.md_initandsetuptake the#elsebranches tomd_onsignal_default(), which sets alist of signals to
SIG_DFLand never touches SIGINT.md_onsignal_autosave()has exactly one call site, inside#ifdef DUMP.signal(SIGINT, leave)appears twice in the whole tree, both in endgamepaths (
main.c:305inquit(),rip.c:237indeath()).main.c:332isthe definition of
leave(), not an installation.devTty.Startcallsterm.MakeRaw, which clearsISIG; Ctrl-C arrives as a key event andterm/tcell.go:169already returns'\x03'. C matches viaraw().So the severity I asserted in #12 was overstated — "the most reachable
robustness gap in the port" does not hold, and the stated reproducer does not
fire. The change is still worth landing, for
kill -INT/kill -QUIT, for aSIGINT delivered to the process group during the
!shell escape, and forB3's genuinely unarmed window. I have recorded the correction on #12.
B2 is the finding I would have missed and care most about. The tests
iterate
for _, sig := range handledSignals()without ever asserting whatthat set contains — so mutating it back to
{SIGHUP, SIGTERM}, reinstatingthe exact pre-PR bug, leaves the suite green. The control mutations failing
(removing
t.Fini(), flippingsavesOnSignal) is what makes thisconclusive: the handler body is covered, the signal set is not. A regression
test that cannot fail on the regression is the defect this gate exists to
catch.
B3 is a genuine functional gap, not a documentation nit. Raw mode is
raised at
main.go:42, handlers install at:72, andg.DeathDemo()sitsbetween them and never returns — so
rogue -druns with the tty raw and nohandler at all. DoD item 1 is unmet on that path. B4 falls out of it: the
uncovered window is after
term.New(), not before, so the commit message,PR body, and
TODO.mdall describe it backwards.M1-M4 to be fixed alongside. M5 (
chooseSeedsilently defaulting on anunparseable
SEED) is pre-existing and explicitly not in scope — flag itand I will file it separately rather than let this PR grow.
f602ecdbbftodfb34be1c4Rework of PR #23 against the review of
f602ecdHead is now
dfb34be, amended into the single commit and force-pushed tosig-leave. Every finding is addressed below; none is skipped and none isrebutted — the review was right on all eight points. Design and the
save/no-save split are unchanged, as instructed.
B1 — lint-red (
goconston the repeated step strings). FIXED.cmd/rogue/main_test.gonow defines the step names once:and uses them in
signalRecorder.AutoSave/Fini/exitand in everyexpectation. No
//nolintanywhere, perMEMORY.md's zero-issues rule.Reworking also surfaced a second real issue that the previous run had not shown
me —
funcorder: unexported method "set" ... should be placed after the exported method "AutoSave"on the new type — which is fixed by orderingAutoSavebefore
set. Final state is 0 issues.On why the earlier "0 issues" claim was wrong: I accept the finding without
qualification — the branch was red. I have adopted the manager's mitigation:
every
make lintandmake checkwas run in a retry loop and the result onlyaccepted when it (a) did not report
parallel golangci-lint is runningand (b)mentioned no file path outside this worktree. The first attempt in this session
did hit the lock, which is exactly the failure mode described.
make checkwasaccepted green twice under that guard, on the final tree.
Also observed and not acted on, since
.golangci.ymlmust stay byte-identical:golangci-lint 2.12.2 emits
The linter 'gomodguard' is deprecated (since v2.12.0) ... Replaced by gomodguard_v2. Flagging it as a tracked action item for thecanonical shared config rather than touching the file here.
B2 — vacuous tests. FIXED, with a mutation proof.
New
TestHandledSignalsSetpins the membership ofhandledSignals()to exactly{SIGHUP, SIGTERM, SIGINT, SIGQUIT}, in both directions (nothing missing, nothing
extra, same length). This is the assertion the file was missing: every other
test iterates that set, so nothing else in the file can fail on the regression.
TestLeaveOnSignalSaveSplitis now driven by the expectation table(
for sig, want := range wantSteps()) instead of byhandledSignals(), so theSIGINT and SIGQUIT entries are genuinely read, and each key is additionally
asserted to be present in
handledSignals()— the test fails twice over if asignal is dropped.
TestPendingSaverArmsBeforeTheGameExistsis new and covers the B3 mechanism.Mutation proof, run as instructed. With
cmd/rogue/main.gotemporarilyreverted to
return []os.Signal{syscall.SIGHUP, syscall.SIGTERM}— the exactpre-PR bug —
make testnow FAILS:The mutation was reverted immediately afterwards; the pushed tree has the full
four-signal set, and the control tests (
...RestoresTerminalBeforeExit,...IgnoresLaterSignals,...RealSignal) still pass under the mutation, whichis what shows the new failures are the set assertion doing its job rather than
collateral.
B3 — handlers installed too late;
rogue -dunprotected. FIXED.Confirmed the mechanism before changing anything:
g.DeathDemo()reachesdeath()(game/rip.go), which callsg.score(...)and then blocksindefinitely in
g.waitFor('\n')beforeg.myExit(). With the install atmain.go:72that whole wait ran with the tty raw and every signal atSIG_DFL.installSignalHandlersis now called immediately afterterm.New()anddefer t.Fini(), before the restore branch and before the demo branch. Sincethere is no game yet at that point, the signature changed from
installSignalHandlers(g saver, t finisher)toinstallSignalHandlers(t finisher) *pendingSaver,and the game is handed over afterwards:
pendingSaverholds the game behind a mutex (setruns on the maingoroutine,
AutoSaveon the signal goroutine — it is guarded for the racedetector, not decoration).
AutoSaveis a no-op while the game is nil, so a signal in the unarmedwindow restores the terminal and exits with nothing to save. Restoring the
terminal is the part that must be armed the instant the tty goes raw, and it
needs no game.
pending.set(g)is called exactly where the old install was, i.e. on the playpath only.
Verification that SIGHUP/SIGTERM autosave is not broken by the reordering:
the play path still reaches
pending.set(g)beforeg.Run(), so a HUP or TERMduring play delegates to the real
RogueGame.AutoSaveexactly as before; thegamepackage is untouched by this PR and its save/restore suite is green. Thenew
TestPendingSaverArmsBeforeTheGameExistsasserts both halves of thehandoff:
fini,exitwith no save beforeset, and a delegated save after it.One deliberate consequence, commented at the call site: the
-ddemo is leftwithout a saver. It now restores the terminal on all four signals (which is the
DoD item that was unmet), but a throwaway demo game must not overwrite the
player's save file — and it never did before, since no handler existed there at
all.
B4 — the exposure analysis was backwards. FIXED in all three places.
Correct statement, now used verbatim in the commit message, the PR body and
TODO.md: nothing is raw beforeterm.New(), so there was never anything tocover there; the uncovered window was after it, and is what B3 closes. All
three now also name the other two residual exposures (
kill -INT/kill -QUITfrom another terminal, and a SIGINT to the process group while the
!shellescape has the screen suspended). The
TODO.mdCompleted Steps entry is keptand corrected rather than rewritten, and
Next Stepis still not rotated.M1 — "a data race" in ARCHITECTURE.md section 9. FIXED.
Reworded. The section now says explicitly that it is not a data race —
tcell guards
Suspend/ResumeandFinialike with the screen mutex, which isalso why the
Finithis PR calls from the signal goroutine is safe — and thatthe real objection is a logical race over screen state: the game goroutine
can redraw into a screen the handler has just suspended, or resume under a
half-finished frame. Your point that the old wording proved too much against
this PR's own code is correct.
M2 —
md_onsignal_autosave"compiled only under DUMP". FIXED.The
savesOnSignalcomment now reads "defined unconditionally, but with itsonly call site, mach_dep.c setup, inside
#ifdef DUMP". The PR body carries thesame correction.
M3 — "Every path restores the terminal" untrue on
-d. FIXED, and it is now true.B3 makes the claim hold, so section 5.3 keeps it and now says why it holds:
the handlers are installed immediately after
term.New()and before the gameexists, and both the restore path and
-d's non-returningDeathDemo()sitinside that window. The sentence is no longer an unsupported assertion.
M4 —
TestLeaveOnRealSignalasserted only a suffix. FIXED.It now asserts the exact step sequence for each signal against the shared
wantSteps()table, so the end-to-end test checks the save/no-save split too —save,fini,exitfor HUP/TERM,fini,exitfor INT/QUIT — rather than just"ends with fini,exit". The
stringsimport is gone with it.M5 — out of scope, flagged not fixed.
chooseSeed(cmd/rogue/main.go) still silently falls back to time+pid whenSEEDis set but unparseable. Pre-existing, untouched here, and left for aseparate issue as directed. Likewise the pre-existing SIGHUP/SIGTERM autosave
data race (#24) is not touched, and the save/no-save semantics are unchanged.
Verification on the final tree
make lint, uncontended, no foreign pathsmake check(fmt-check+lint+test), under the retry guardmake test(-timeout 30s -race -cover).golangci.ymlsha256021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb, not in diffgame/testdata/goldenscmd/rogue/main.go,cmd/rogue/main_test.go,ARCHITECTURE.md,TODO.md(closes #12), single amended commitmake fmton touched markdownprettier --checkcleanWork was done in a throwaway worktree; the shared clone was left on
main,clean, and
c-master/modern-roguewere only ever read viagit show.Review of PR #23 (head
dfb34be) — VERDICT: PASS /merge-readyFresh independent review. I did not author, rework, or previously review this
change, and I re-verified every earlier finding from scratch rather than
accepting the rework report. Checked against issue #12 and all three of its
comments (the two comments are authoritative over the body),
TODO.md,MEMORY.md,README.md,ARCHITECTURE.md§5.3 and §9, and the C referenceread only via
git show origin/c-master:. Verified in a throwaway worktree atdfb34be, since removed; the shared clone was left onmain, clean.1. The new concurrency code —
pendingSaverThis is where I looked hardest, since it is the part the previous review never
saw. It is correct.
Race-freedom.
cmd/rogue/main.go:136-161.pendingSaverhas exactly onemutable field,
game saver, and exactly two accessors.AutoSave(
main.go:144-153) takesp.mu,defers the unlock, nil-checks and delegates.set(main.go:156-161) takesp.mu,defers the unlock, assigns. Every readand every write of
p.gameis inside the lock; nothing escapes it — no pointerto the field is handed out, and
AutoSavedoes not release the lock beforedelegating. The
*pendingSaveritself is allocated ininstallSignalHandlers(
main.go:219) before thegostatement atmain.go:221, so the goroutine'sview of it is established by the happens-before edge of the
gostatement, andthe value returned to
runis the same pointer.Interleavings. The only concurrent pair is
seton the main goroutineagainst
AutoSaveon the signal goroutine, and there are only two orders:AutoSaveacquires first:p.gameis nil, nothing is written, and thehandler proceeds to
Finithenexit(0). The signal landed at a moment whenthe game had existed for a handful of instructions and had never run a turn,
so there is nothing to rescue. Correct.
setacquires first: the handler delegates to the realgame.RogueGame.AutoSave. Correct.There is no third state and no torn read, because the field is a single word
written under the lock. I could not construct a bad interleaving.
Empirically. I built a throwaway copy of the head tree and added a probe
test that runs 500 iterations of
leaveOnSignalagainst a concurrentpending.set, both goroutines racing for the samependingSaver, and ran itthrough
make test(-timeout 30s -race -cover). Clean, no race reports. Theprobe was discarded; nothing was committed.
Deadlock.
AutoSaveholdsp.muacross the delegated call. That is safehere because
setis called exactly once, frommain.go:83, and the realAutoSavenever re-enterspendingSaver. See N3 below for the only caveat.2.
-drestores the tty without touching the save file — CONFIRMEDrun()(cmd/rogue/main.go:29-88) reachespending.set(g)only atmain.go:83. The-dbranch atmain.go:74-81callsg.DeathDemo()andreturns ahead of it, sosetis provably not reached on the demo path — thedemo game never becomes the handler's saver. A signal during
rogue -dtherefore runs
savesOnSignal(main.go:205-207), and for SIGHUP/SIGTERM callspendingSaver.AutoSave, which findsp.game == niland returns withouttouching the filesystem, then
t.Fini()thenexit(0). Terminal restored, savefile untouched. This is the DoD 1 gap the previous review raised as B3, and it
is closed:
g.DeathDemo()(game/rip.go:268-277) reachesdeath(), whichblocks indefinitely in
waitFor('\n'), and that whole stretch is now inside thearmed window.
3. SIGHUP/SIGTERM autosave on the play path — UNCHANGED
Compared against
4aa4bab:cmd/rogue/main.go. The oldinstallAutosave(g, t)was invoked at exactly the point
pending.set(g)now is: after the restore /new-game branch, after the
-dearly return, immediately beforeg.Run(). Thehandler body performs the same three steps in the same order —
g.AutoSave(),t.Fini(),os.Exit(0). The restore path still reachesset(g)(the-dguard atmain.go:62is false there), so a restored gamestill autosaves on HUP/TERM. No file under
game/is in the diff, and thesave/restore suite passes. No regression.
4. Single-signal-read ordering — SURVIVED THE REFACTOR
notifySignals(main.go:229-237) creates one channel of capacity 1 andregisters it.
installSignalHandlers(main.go:218-224) starts exactly onegoroutine.
leaveOnSignal(main.go:247-254) performs exactly one channelreceive, at
main.go:248, and does not loop. A second signal arriving mid-AutoSavetherefore sits in the buffer (or is dropped byos/signal) and cannever reach
exit.Worth noting explicitly because it is easy to get wrong:
notifySignals()atmain.go:221is an argument to thegostatement, so per the Go spec it isevaluated on the calling goroutine before the new goroutine starts.
signal.Notifyis therefore in force by the timeinstallSignalHandlersreturns, not at some later scheduling point. The arming is synchronous, which is
the whole premise of moving the call to
main.go:56.TestLeaveOnSignalIgnoresLaterSignals(main_test.go:204-224) reproduces theinterleaving with a saver that queues a second signal from inside the save, and
asserts
len(ch) == 1afterwards.5. B2 non-vacuity — REPRODUCED MYSELF, and the failures are for the right reason
I did not take the rework's word for this. I copied the head tree, reduced
handledSignals()(cmd/rogue/main.go:166-170) to{syscall.SIGHUP, syscall.SIGTERM}— the exact pre-PR bug — and ranGOFLAGS=-count=1 make test:Both failures are the set assertion doing its job, not collateral: the messages
come from
main_test.go:113/118(the membership check) andmain_test.go:175(the
slices.Contains(handledSignals(), sig)guard), and the verbose rerunshows
TestLeaveOnSignalRestoresTerminalBeforeExit,TestLeaveOnSignalIgnoresLaterSignals,TestLeaveOnRealSignalandTestPendingSaverArmsBeforeTheGameExistsall still PASS under the mutation.That contrast is exactly what proves the new assertions are load-bearing. The
mutated copy was deleted; the pushed tree is unmodified.
The structural fix is right too:
TestLeaveOnSignalSaveSplit(
main_test.go:170-197) is now driven byfor sig, want := range wantSteps(),so the SIGINT and SIGQUIT rows of the expectation table are genuinely read
rather than being dead data keyed off a set that no longer contains them.
6. B1 — lint is clean
Measured under the retry protocol. Four accepted
make checkruns atdfb34be, none of which reportedparallel golangci-lint is runningand noneof which named a path outside my own worktree:
goconstis gone: the step strings are hoisted tostepSave/stepFini/stepExitatcmd/rogue/main_test.go:18-22and used everywhere, with no//nolintadded anywhere in the diff.funcorderis satisfied by placingAutoSave(main.go:144) ahead ofset(main.go:156).The only linter output is the pre-existing, config-level
The linter 'gomodguard' is deprecated (since v2.12.0)warning. It is not anissue, it is present on
maintoo, and fixing it would require editing.golangci.yml, whichMEMORY.md:25-27forbids. Correctly flagged and notacted on.
7. B3/B4 — every path, and the direction of the window
Every path. I enumerated them rather than checking only the two that were
fixed:
-sscoreboard (main.go:37-41)term.New()term.New()error (main.go:43-48)s.Fini()itself insideterm/tcell.gobefore returning the errormain.go:64-69)defer t.Fini()atmain.go:49-ddeath demo (main.go:74-81)main.go:56; normal end viamyExit→scr.Fini()(game/rip.go:17-20)main.go:85)myExitrun()defer t.Fini()runs during unwindingflag.Parse()usage errorterm.New()So §5.3's claim holds for every path that ever puts the tty in raw mode. See N1
for the one instruction-scale caveat, which I am not treating as blocking.
Direction of the window. All three records now state it correctly and
consistently:
before term.New(), so there was never anything to cover there."
term.New()… Nothing is raw beforeterm.New(), so there was never anything to cover there — the earlierrevision of this description had that backwards."
TODO.md: "the window afterterm.New(): nothing is raw before it".B4 is fixed in all three places.
8. M1 and M2 — verified against the sources, not against the report
M1.
ARCHITECTURE.md:1750-1753now reads "That is not a data race — tcellguards
Suspend/ResumeandFinialike with the screen mutex, which is alsowhy the
Finithis port does call from the signal goroutine is safe — it is alogical race over the screen state". That is the correct characterisation and
it no longer proves too much against this PR's own
t.Fini()from the signalgoroutine. Fixed.
M2.
cmd/rogue/main.go:184-186now reads "(md_onsignal_autosave, mdport.c —defined unconditionally, but with its only call site, mach_dep.c setup, inside
#ifdef DUMP)". Checked against the C source directly:
mdport.c:216-254definesmd_onsignal_autosave()with no enclosing#ifdef DUMP— the only conditionals inside it are the per-signal#ifdef SIGxxxguards. Definition is unconditional. Confirmed.mach_dep.c setup()is the sole call site, and it is inside#ifdef DUMP / md_onsignal_autosave(); / #else / md_onsignal_default(); / #endif. Confirmed.Fixed, and now accurate.
Independent re-verification of the two disputed premises
I re-checked both from the C sources and the module cache rather than inheriting
the earlier conclusions. Both hold.
md_onsignal_default()(mdport.c:141-176) sets SIGHUP, SIGQUIT, SIGILL,SIGTRAP, SIGIOT, SIGEMT, SIGFPE, SIGBUS, SIGSEGV, SIGSYS and SIGTERM to
SIG_DFLand never mentions SIGINT.md_init(mdport.c:133-137) andsetup(mach_dep.c) both take the non-DUMP branch in the shipped build. Soduring play, INT and QUIT are
SIG_DFL: no handler, noendwin().signal(SIGINT, leave)appears exactly twice in the tree:main.c:305(inquit()after the player confirms) andrip.c:237(indeath(), right aftersignal(SIGINT, SIG_IGN)atrip.c:235). Both endgame.main.c:332is thedefinition of
leave(), not an installation.md_onsignal_autosave()wires HUP→auto_save, QUIT→endit, INT→quit, andthe fault signals to
auto_save— matching the §9 rows exactly.signal.Notify(tty.sig, syscall.SIGWINCH)attty_unix.go:108andstdin_unix.go:108, and nothingelse anywhere in the module. The old §5.3 claim that tcell handled SIGTSTP was
false; the correction at
ARCHITECTURE.md:1516-1517is right.Issue #12's body is wrong on both counts and its stated severity was overstated,
as the issue's own later comments now record. The PR's handling — recording the
corrections in
ARCHITECTURE.md, the commit message andTODO.mdrather thanquietly working around them — is the right call.
Standard gate
make checkgreen under the retry protocol0 issues, no lock collision, no foreign pathsmake test(-timeout 30s -race -cover),GOFLAGS=-count=1, repeatedsetvsleaveOnSignalunder-race)make fmtcleangofmt -lempty,prettier --checkclean.golangci.ymlsha256021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb, not in diffscript/touchedgame/testdata/goldens regeneratedARCHITECTURE.md,TODO.md,cmd/rogue/main.go,cmd/rogue/main_test.gosneak <sneak@sneak.berlin>) all clean(closes #12)TODO.mdCompleted Steps entry added,Next Stepnot rotatedTODO.mdhunk is 53 insertions, 0 deletionsmaindfb34beis a fast-forward descendant of4aa4bab; Gitea reportsmergeable: true.gitea/or.github/workflows and Gitea reports 0 statuses. Not aneeds-checkscaseAutoSavebegins atpending.set(g)(main.go:83), the exact pointinstallAutosaveused to be calledchooseSeedsilent default on unparseableSEED)main.go:258-271is byte-identical to4aa4baband absent from the diffsaver,finisher,pendingSaver,handledSignals,savesOnSignal,installSignalHandlers,notifySignals,leaveOnSignalall read cleanly and match the file's existing stylet.Parallel()in all tests//nolint:testpackageonmain_test.gotestpackageexemptspackage main, sonolintlintwould reject the directive as unused; explained atmain_test.go:3-5Non-blocking observations
None of these block the merge. Recording them for accuracy.
cmd/rogue/main.go:43-56— a residual unarmed window remains, roughlya microsecond wide.
term.New()raises raw mode insides.Init(), andsignal.Notifydoes not take effect untilinstallSignalHandlersatmain.go:56. Between them lie the error check and thedefer. This isinstruction-scale rather than the indefinite
waitForwindow B3 closed, andclosing it entirely would mean registering the channel before
term.New()andhanding the finisher over the way the saver is handed over now. §5.3's
"every path restores the terminal … before exiting" is absolute phrasing that
overstates by this much. Not worth a rework; worth knowing.
ARCHITECTURE.md:1529-1531quotes a sentence that does not exist. Thetext reads: That ordering is what makes "every path restores the terminal via
Terminal.Finibefore exiting" actually true. That exact phrase occursnowhere else in
ARCHITECTURE.md, and did not occur at4aa4babeither, sothe quotation marks have no antecedent and read oddly. Asserting it directly
would be clearer.
cmd/rogue/main.go:144-153holdsp.muacross the delegatedAutoSave. Harmless today:setis called once, early, and the realAutoSavenever re-enterspendingSaver. It would become amain-goroutine stall if
setever became repeatable (e.g. re-armed after arestore-in-place). A one-line note would future-proof it.
cmd/rogue/main.go:148nil-checks the interface, not the pointer. Atyped-nil
(*game.RogueGame)(nil)passed tosetwould makep.game == nilfalse and panic on delegation. Not reachable from
run(), wheresetis onlyever handed a non-nil
g. Noted for completeness.-dcomment atcmd/rogue/main.go:75-77is more defensive thanload-bearing. A demo game from
game.Newhas an emptyFileName, andgame.RogueGame.AutoSave(game/save.go:673-678) is already a no-op in thatcase, so the demo could not have overwritten a save file even with a saver
wired in. The split is still the right design — it does not depend on that
invariant holding — but the comment implies a sharper hazard than exists.
Verdict
PASS —
merge-ready. All four blocking findings from the review off602ecdare genuinely fixed, verified independently rather than accepted fromthe rework report: lint is
0 issuesacross four accepted runs, the mutationthat reinstates the pre-PR signal set now fails two tests for the correct
reason while the four control tests still pass,
rogue -dis inside the armedwindow and provably never becomes the handler's saver, and the exposure window
is described as being after
term.New()in all three records. M1 and M2 arefixed and check out against the C source. The new
pendingSaveris genuinelyrace-free — every access under the mutex, no escape, no bad interleaving
constructible, and race-clean under a 500-iteration concurrent probe. The
single-signal-read guarantee survives the restructure, and
signal.Notifyisestablished synchronously because
notifySignals()is evaluated on the callinggoroutine at the
gostatement. SIGHUP/SIGTERM autosave on the play path isbyte-for-byte the previous behavior. #24 and M5 were both correctly left alone.
Manager notes (the fresh review is in its own comment above).
Verdict accepted: PASS. Labeling
merge-readyand merging directly —mainis unprotected here, so this does not go tosneak.Four distinct agents touched this PR: implementer, first reviewer (FAIL),
reworker, and a fresh second reviewer. No agent reviewed its own work.
The concurrency verification is what earns the merge. The rework
introduced a new mutable object shared between the signal goroutine and the
main goroutine, which is exactly the kind of change that passes review on
plausible reasoning and fails in production. It was not taken on reasoning:
p.gamewas checked to be insidep.mu.*pendingSaverisallocated before the
gostatement, so the goroutine's view isestablished by that.
set-vs-leaveOnSignalprobe under-racewas run and came back clean.
The sharpest observation is one I would have missed:
notifySignals()is ago-statement argument, so it evaluates on the calling goroutine. Thearming is therefore synchronous, which is precisely what makes moving the
install up to
main.go:56sound rather than merely earlier. That is the load-bearing detail behind the B3 fix.
B2 was reproduced first-hand, not accepted from the rework's report:
mutating
handledSignals()back to{SIGHUP, SIGTERM}fails the two setassertions while the four control tests still pass — failing for the right
reason, not collateral damage. The whole point of B2 was that a regression
test which cannot fail on the regression is worthless, so verifying the fix
by report alone would have repeated the original error.
B3 was checked exhaustively rather than spot-checked — all seven exit
paths enumerated, every path that raises raw mode restores it. That is the
right standard for a claim as absolute as "every path restores the terminal",
which §5.3 now makes.
Both disputed premises from issue #12 were re-verified by this reviewer
independently and both hold. Three agents have now confirmed them against
the C sources. The correction stands: my original severity claim was wrong,
and the record on #12 says so.
Lint was measured under the contention protocol — four accepted
make checkruns, no lock collision, no foreign paths. Given that the previousround produced a false green from a poisoned shared cache, that discipline is
now the standard for this repo.
N1-N5 are non-blocking and deliberately not folded in. N1 (a
microsecond-wide unarmed window between
term.New()and the install) and N3(
p.muheld across the delegatedAutoSave) are the only two with any teeth,and neither is reachable in a way that matters today. N5 is a nice catch —
the
-dcomment overstates the hazard, since a freshgame.Newhas an emptyFileNameandAutoSaveis already a no-op there — but it is a commentoverstating safety, not code being unsafe.
Next: dispatching #24, the pre-existing SIGHUP/SIGTERM autosave data race.
This PR put the signal path under test, which is what makes #24 tractable.