Harden shutdown: no segfault closing mid-load (thread cleanup + graceful Ctrl+C)

app/gui.py

@@ -7,6 +7,7 @@ Run with::
 import datetime
 import json
 import logging
+import signal
 import sys
 import threading
 from pathlib import Path
@@ -158,7 +159,9 @@ class CoverLoader(QObject):
                 else:
                     self.failed.emit(self.gen, i, self.items[i]["name"])
         finally:
-            pool.shutdown(wait=True, cancel_futures=True)
+            # Return promptly on cancel/exit instead of blocking the GUI thread
+            # on in-flight network timeouts during shutdown.
+            pool.shutdown(wait=not self._cancel.is_set(), cancel_futures=True)
         self.finished.emit()
 
 
@@ -480,7 +483,7 @@ class CoverShowcase(QWidget):
         return QIcon(pm)
 
     def _on_loaded(self, gen, index, image):
-        if gen != self._generation:
+        if self._closing or gen != self._generation:
             return
         item = self.list.item(index)
         if item is not None:
@@ -502,7 +505,7 @@ class CoverShowcase(QWidget):
             self.play_requested.emit(data)
 
     def _on_failed(self, gen, index, name):
-        if gen != self._generation:
+        if self._closing or gen != self._generation:
             return
         if index not in self.missing:
             self.missing.append(index)
@@ -510,6 +513,8 @@ class CoverShowcase(QWidget):
         self._update_status()
 
     def _on_loading_done(self):
+        if self._closing:
+            return
         sender = self.sender()
         if sender is not None and getattr(sender, "gen", None) != self._generation:
             return
@@ -517,6 +522,8 @@ class CoverShowcase(QWidget):
         self._update_status()
 
     def _update_status(self):
+        if self._closing:
+            return
         if self._loading:
             self.status.setText("Loading covers…")
             self.missing_changed.emit(0)
@@ -1541,7 +1548,9 @@ class StoreCoverLoader(QObject):
                     if not img.isNull():
                         self.loaded.emit(self.gen, row, _fit_image(img, self.icon_w, self.icon_h))
         finally:
-            pool.shutdown(wait=True, cancel_futures=True)
+            # Return promptly on cancel/exit instead of blocking the GUI thread
+            # on in-flight network timeouts during shutdown.
+            pool.shutdown(wait=not self._cancel.is_set(), cancel_futures=True)
         self.finished.emit()
 
 
@@ -2353,7 +2362,7 @@ class StorePage(QWidget):
         thread.start()
 
     def _on_date_loaded(self, gen, row, date):
-        if gen != self._generation or not date:
+        if self._closing or gen != self._generation or not date:
             return
         if 0 <= row < len(self._filtered):
             self._filtered[row]["release_date"] = date
@@ -2376,7 +2385,7 @@ class StorePage(QWidget):
         thread.start()
 
     def _on_cover_loaded(self, gen, row, image):
-        if gen != self._generation:
+        if self._closing or gen != self._generation:
             return
         item = self.grid.item(row)
         if item is not None:
@@ -4130,6 +4139,7 @@ class Ps1Page(QWidget):
         self._preview_gen = 0
         self._preview_threads = []
         self._preview_workers = []
+        self._closing = False
 
         layout = QVBoxLayout(self)
         bar = QHBoxLayout()
@@ -4228,7 +4238,7 @@ class Ps1Page(QWidget):
         self._preview_workers.append(worker)
 
     def _on_preview_result(self, gen, game_id, icon0, pic0, pic1):
-        if gen != self._preview_gen:
+        if self._closing or gen != self._preview_gen:
             return
         self.preview_icon0.setText("")
         self.preview_pic0.setText("")
@@ -4276,6 +4286,8 @@ class Ps1Page(QWidget):
         self._thread.start()
 
     def _on_results(self, entries):
+        if self._closing:
+            return
         # Only show discs that still need converting; converted games already
         # appear in the Library tab.
         entries = [e for e in entries if e["kind"] == "disc" and e.get("status") != "converted"]
@@ -4291,8 +4303,23 @@ class Ps1Page(QWidget):
             self.table.selectRow(0)
 
     def _on_failed(self, message):
+        if not self._closing:
             self.status.setText(f"PS1 scan failed: {message}")
 
+    def shutdown(self):
+        self._closing = True
+        if self._thread is not None and _thread_running(self._thread):
+            self._thread.quit()
+            self._thread.wait()
+        for t in self._preview_threads:
+            if _thread_running(t):
+                t.quit()
+                t.wait()
+        self._preview_threads = []
+        self._preview_workers = []
+        self._thread = None
+        self._worker = None
+
     def _convert_selected(self):
         row = self.table.currentRow()
         if row < 0 or row >= len(self._entries):
@@ -5685,6 +5712,8 @@ class MainWindow(QMainWindow):
             self.psp_page.shutdown()
         if hasattr(self, "saves_page"):
             self.saves_page.shutdown()
+        if hasattr(self, "ps1_page"):
+            self.ps1_page.shutdown()
         event.accept()
 
 
@@ -5718,6 +5747,21 @@ def main():
     window.show()
     log.info("main window ready")
     threading.Thread(target=_start_bundle_check, args=(window,), daemon=True).start()
+
+    # Ctrl+C should close the window gracefully (running closeEvent's thread
+    # cleanup) rather than tearing Qt down mid-thread, which segfaults.
+    interrupt = {"pending": False}
+
+    def _sigint_handler(signum, frame):
+        interrupt["pending"] = True
+
+    signal.signal(signal.SIGINT, _sigint_handler)
+    sigint_timer = QTimer()
+    sigint_timer.setInterval(100)
+    sigint_timer.timeout.connect(
+        lambda: window.close() if interrupt["pending"] else None)
+    sigint_timer.start()
+
     return app.exec()