fix: exit on the window's signal when it closes

A closed window under a changing screen failed the draw (EIO, or a
termios.error from the SIGCONT that comes with SIGHUP) before the
signal was read, and the run ended on 1 with a crash log kept.

install.ps1

@@ -11,7 +11,7 @@
 
     $ErrorActionPreference = "Stop"
     $defaultInstallUrl = "https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-    $defaultInstallSha256 = "e2cc5f073a8226fe26b0513ebd25f00de6f3f613d8c9851473c2d30b53356f48"
+    $defaultInstallSha256 = "c2a66e6b26004e96ef5f59a7fb5a2ed65bcaa9afc7602bd3e0d71f50cc561056"
     $maximumInstallerBytes = 2MB
     $installerExit = 0
     $installer = if ($PSScriptRoot) { Join-Path $PSScriptRoot "install.py" } else { $null }

install.py

@@ -12500,13 +12500,14 @@ def run_tui(args: argparse.Namespace) -> int:
             if terminating["signal"] and state.screen == "result":
                 # The result is printed in the terminal on the way out.
                 state.exit_code = state.code if state.code is not None else 1
-    except Exception:  # noqa: BLE001
-        # A traceback is where every reporter of #71, #73 and #74 stopped:
-        # it goes to a file, and the terminal says one sentence.
-        crash = work / "error.log"
-        crash.write_text(traceback.format_exc(), encoding="utf-8")
-        state.log, state.code, state.exit_code = str(crash), 1, 1
-        state.stack = ["crashed"]
+    except Exception as exc:  # noqa: BLE001
+        if flags["term"] or _closed_terminal(exc):
+            # The window closed under a screen that was changing, or the
+            # SIGCONT that comes with its SIGHUP put the screen back: the
+            # write failed before the signal was read. That is its exit.
+            state.exit_code = 128 + (flags["term"] or getattr(signal, "SIGHUP", 1))
+        else:
+            _tui_crashed(state, work)
     finally:
         # Each step on its own: a write the closed window refuses, or a
         # second signal while the install writes its summary, must not
@@ -12560,6 +12561,32 @@ def _tui_startup(args: argparse.Namespace) -> tuple[TuiState, list[tuple]] | Non
     return tui_start(args, os_type)
 
 
+# What a write to a closed window or a closed pipe answers.
+_CLOSED_TERMINAL = frozenset({errno.EIO, errno.EPIPE, errno.ENXIO})
+
+
+def _closed_terminal(exc: BaseException) -> bool:
+    """Whether exc is the terminal gone: an OSError, or a termios.error,
+    whose first argument is the errno, answering EIO, EPIPE or ENXIO."""
+    if isinstance(exc, OSError):
+        return exc.errno in _CLOSED_TERMINAL
+    if type(exc).__name__ == "error" and type(exc).__module__ == "termios":
+        return bool(exc.args) and exc.args[0] in _CLOSED_TERMINAL
+    return False
+
+
+def _tui_crashed(state: TuiState, work: Path) -> None:
+    """A traceback is where every reporter of #71, #73 and #74 stopped: it
+    goes to a file, and the terminal says one sentence."""
+    crash = work / "error.log"
+    try:
+        crash.write_text(traceback.format_exc(), encoding="utf-8")
+    except OSError as exc:
+        print(f"The error could not be written to {crash}: {exc}", file=sys.stderr)
+    state.log, state.code, state.exit_code = str(crash), 1, 1
+    state.stack = ["crashed"]
+
+
 def _restore_handlers(handlers: dict) -> None:
     for number, previous in handlers.items():
         signal.signal(number, previous)

install.sh

@@ -18,7 +18,7 @@ esac
 TEMP_INSTALLER=""
 TEMP_DIRECTORY=""
 DEFAULT_INSTALL_URL="https://raw.githubusercontent.com/Abdess/retrobios/main/install.py"
-DEFAULT_INSTALL_SHA256="e2cc5f073a8226fe26b0513ebd25f00de6f3f613d8c9851473c2d30b53356f48"
+DEFAULT_INSTALL_SHA256="c2a66e6b26004e96ef5f59a7fb5a2ed65bcaa9afc7602bd3e0d71f50cc561056"
 MAX_INSTALLER_BYTES=2097152
 
 cleanup() {

tests/test_install_tui.py

@@ -1444,13 +1444,14 @@ class CleanupSurvivesABrokenTerminal(unittest.TestCase):
                 mock.patch.object(sys, "stderr", out):
             code = install.run_tui(_args())
             self.assertIs(sys.stdout, out)
-        self.assertEqual(code, 1)
+        # A window that answers EIO is a closed window: its signal's code,
+        # not a crash.
+        self.assertEqual(code, 129)
         # The farewell found no terminal: what still flushes at exit goes to
         # the null device, and the exit code stays the one returned.
         self.assertEqual(os.fstat(screen_fd).st_rdev, os.stat(os.devnull).st_rdev)
-        # The crash keeps its log, marked kept, and nothing else of the run.
-        self.assertEqual(sorted(path.name for path in work.iterdir()),
-                         ["error.log", "kept", "owner"])
+        # No crash log is kept, and nothing else of the run.
+        self.assertFalse(work.exists())
         self.assertEqual(termios.tcgetattr(slave), before)
         for number, handler in handlers.items():
             self.assertEqual(signal.getsignal(number), handler)
@@ -2859,6 +2860,31 @@ class EndToEnd(unittest.TestCase):
                 self.assertTrue(os.WIFEXITED(status))
                 self.assertEqual(term.status, 129)
 
+    def test_closing_the_window_while_it_installs(self):
+        """The changing screen fails to draw on the closed window: that is
+        the window's signal, not a crash with a log kept."""
+        repo = self.repo(GameDataRepository, slow=True)
+        scratch = repo.root / "scratch"
+        scratch.mkdir()
+        self.env["TMPDIR"] = str(scratch)
+        term = self.start("--platform", "retroarch", "--dest", str(repo.dest), "--jobs", "1")
+        term.wait("> Install")
+        term.send("\r")
+        term.wait("1 of 6 files")
+        os.close(term.fd)
+        end = time.monotonic() + 20
+        while time.monotonic() < end:
+            pid, status = os.waitpid(term.pid, os.WNOHANG)
+            if pid:
+                break
+            time.sleep(0.05)
+        else:
+            os.kill(term.pid, 9)
+            self.fail("still running once its window closed")
+        term.status = os.WEXITSTATUS(status)
+        self.assertEqual(term.status, 129)
+        self.assertEqual(list(scratch.glob("retrobios-tui-*/error.log")), [])
+
     def test_a_desktop_names_its_keys_and_a_pad_its_buttons(self):
         self.repo()
         for env, bar in (({"DISPLAY": ":0"}, "Enter Continue  Esc Quit  ? Help"),