Add support for TN3270 alarm and VT100 bell

oec/controller.py

@@ -5,7 +5,7 @@ oec.controller
 
 import time
 import logging
-from coax import poll, poll_ack, KeystrokePollResponse, ReceiveTimeout, \
+from coax import poll, poll_ack, PollAction, KeystrokePollResponse, ReceiveTimeout, \
                  ReceiveError, ProtocolError
 
 from .terminal import Terminal, read_terminal_ids
@@ -166,7 +166,9 @@ class Controller:
 
         self.last_poll_time = time.perf_counter()
 
-        poll_response = poll(self.interface, timeout=1)
+        poll_action = self.terminal.get_poll_action() if self.terminal else PollAction.NONE
+
+        poll_response = poll(self.interface, poll_action, timeout=1)
 
         if poll_response:
             try:

oec/terminal.py

@@ -5,7 +5,8 @@ oec.terminal
 
 import time
 import logging
-from coax import read_terminal_id, read_extended_id, ReceiveError, ProtocolError
+from coax import read_terminal_id, read_extended_id, PollAction, ReceiveError, \
+                 ProtocolError
 
 from .display import Dimensions, Display 
 from .keyboard import Keyboard
@@ -67,3 +68,16 @@ class Terminal:
 
         self.display = Display(interface, dimensions)
         self.keyboard = Keyboard(keymap)
+
+        self.alarm = False
+
+    def sound_alarm(self):
+        self.alarm = True
+
+    def get_poll_action(self):
+        if self.alarm:
+            self.alarm = False
+
+            return PollAction.ALARM
+
+        return PollAction.NONE

oec/tn3270.py

@@ -71,6 +71,8 @@ class TN3270Session(Session):
 
         self.emulator = Emulator(self.telnet, rows, columns)
 
+        self.emulator.alarm = lambda: self.terminal.sound_alarm()
+
     def terminate(self):
         if self.telnet:
             self._disconnect_host()

oec/vt100.py

@@ -86,6 +86,14 @@ class VT100Session(Session):
 
         self.vt100_screen.write_process_input = lambda data: self.host_process.write(data.encode())
 
+        # Unfortunately multiple VT100 bells will be replaced with a single 3270 terminal
+        # alarm - also because the alarm is only sounded on terminal POLL the alarm sound
+        # may appear out of sync with the terminal.
+        #
+        # A better approach may be to perform a flush when the bell is encountered but
+        # that does not appear possible with the standard pyte ByteStream.
+        self.vt100_screen.bell = lambda: self.terminal.sound_alarm()
+
         self.vt100_stream = pyte.ByteStream(self.vt100_screen)
 
     def start(self):