Merge branch 'main' into 147-sig-activity-changes

# Conflicts:
#	core/constants.py
#	pyproject.toml

providers/spot/dxcluster.py

@@ -1,7 +1,8 @@
 import logging
 import re
+import socket
 from datetime import datetime
-from threading import Event, Thread
+from threading import Event, Lock, Thread
 
 import pytz
 import telnetlib3
@@ -40,6 +41,7 @@ class DXCluster(SpotProvider):
             self._LINE_PATTERN_ALLOW_RBN if self._allow_rbn_spots else self._LINE_PATTERN_EXCLUDE_RBN
         )
         self._telnet = None
+        self._telnet_lock = Lock()
         self._thread = None
         self._stop_event = Event()
 
@@ -49,10 +51,15 @@ class DXCluster(SpotProvider):
 
     def stop(self):
         self._stop_event.set()
-        if self._telnet:
-            self._telnet.close()
+        with self._telnet_lock:
+            if self._telnet:
+                try:
+                    self._telnet.sock.shutdown(socket.SHUT_RDWR)
+                except (AttributeError, OSError):
+                    pass
+                self._telnet.close()
         if self._thread:
-            self._thread.join(timeout=15)
+            self._thread.join(timeout=5)
             if self._thread.is_alive():
                 logger.warning(f"DX Cluster {self._hostname} worker thread did not exit on time and will be killed.")
 
@@ -63,7 +70,14 @@ class DXCluster(SpotProvider):
                 try:
                     self.status = "Connecting"
                     logger.info(f"DX Cluster {self._hostname} connecting...")
-                    self._telnet = telnetlib3.Telnet(self._hostname, self._port)
+                    new_telnet = telnetlib3.Telnet(self._hostname, self._port)
+                    with self._telnet_lock:
+                        self._telnet = new_telnet
+                        if self._stop_event.is_set():
+                            # stop() was called while we were connecting, close the connection rather than trying to
+                            # read when we know it won't work
+                            new_telnet.close()
+                            break
                     self._telnet.read_until(self._login_prompt.encode("latin-1"))
                     self._telnet.write(f"{self._login_callsign}\n".encode("latin-1"))
                     connected = True