add files

fichero/printer.py

@@ -8,6 +8,7 @@ Device class: AiYinNormalDevice (LuckPrinter SDK)
 
 import asyncio
 import sys
+import errno
 from collections.abc import AsyncGenerator
 from contextlib import asynccontextmanager
 
@@ -427,14 +428,31 @@ async def connect(
                     yield pc
                     return
             except (PrinterError, PrinterTimeout) as exc:
+                # On Linux, a stale BlueZ device state can cause RFCOMM connect()
+                # to fail with [Errno 12] Out of memory. This is a known quirk.
+                # We treat this specific error as a signal to fall back to BLE.
+                if isinstance(exc.__cause__, OSError) and exc.__cause__.errno == errno.ENOMEM:
+                    print(
+                        "Classic Bluetooth connection failed with [Errno 12] Out of memory. "
+                        "Falling back to BLE connection."
+                    )
+                    classic = False  # Modify flag to trigger BLE path below
+                    last_exc = exc
+                    break
                 last_exc = exc
-        if last_exc is not None:
-            raise PrinterError(
-                f"Classic Bluetooth connection failed for '{address}'. "
-                f"Tried channels: {channels}. Last error: {last_exc}"
-            ) from last_exc
-        raise PrinterError(f"Classic Bluetooth connection failed for '{address}'.")
-    else:
+
+        # If the 'classic' flag is still true, it means the loop completed without
+        # hitting the ENOMEM fallback case, so all classic attempts failed.
+        if classic:
+            if last_exc is not None:
+                raise PrinterError(
+                    f"Classic Bluetooth connection failed for '{address}'. "
+                    f"Tried channels: {channels}. Last error: {last_exc}"
+                ) from last_exc
+            raise PrinterError(f"Classic Bluetooth connection failed for '{address}'.")
+
+    # If classic=False initially, or if it was set to False for the ENOMEM fallback:
+    if not classic:
         target = await resolve_ble_target(address)
         def _is_retryable_ble_error(exc: Exception) -> bool:
             msg = str(exc).lower()