From a89547dadb2928083b7bd859f99cca9c8c61f74b Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Mon, 23 Sep 2013 08:37:39 +0200
Subject: [PATCH] add a ThreadFunction class and use it

---
 libtuer.py | 30 ++++++++++++++++++++++++++++++
 ringd      | 24 ++++++------------------
 2 files changed, 36 insertions(+), 18 deletions(-)

diff --git a/libtuer.py b/libtuer.py
index a655fcd..0df4051 100644
--- a/libtuer.py
+++ b/libtuer.py
@@ -19,3 +19,33 @@ logger = Logger()
 def log (what):
 	logger.log(what)
  
+
+# Threaded callback class
+class ThreadFunction():
+	_CALL = 0
+	_TERM = 1
+	
+	def __init__(self, f):
+		self._f = f
+		self._q = queue.Queue()
+		self._t = threading.Thread(target=self._thread_func)
+		self._t.start()
+	
+	def _thread_func(self):
+		while True:
+			(cmd, data) = self._q.get()
+			# run command
+			if cmd == _CALL:
+				self._f(*data)
+			elif cmd == _TERM:
+				assert data is None
+				break
+			else:
+				raise NotImplementedError("Command %d does not exist" % cmd)
+	
+	def __call__(self, *arg):
+		self._q.put((self._CALL, arg))
+	
+	def stop(self):
+		self._q.put((_TERM, None))
+		self._t.join()
diff --git a/ringd b/ringd
index 201322f..b6a27f9 100755
--- a/ringd
+++ b/ringd
@@ -1,7 +1,7 @@
 #!/usr/bin/python3
 import time, socket, atexit
 import queue, threading, select
-from libtuer import log
+from libtuer import log, ThreadFunction
 import RPi.GPIO as GPIO
 GPIO.setmode(GPIO.BOARD)
 atexit.register(GPIO.cleanup)
@@ -9,6 +9,7 @@ atexit.register(GPIO.cleanup)
 tuerSock = "/run/tuer.sock"
 ringPin = 18
 
+
 # Main classes
 class PinWatcher():
 	def __init__(self, pin, histlen):
@@ -21,17 +22,8 @@ class PinWatcher():
 		self._newstate = None # != None iff we are currently seeing a state change
 		self._newstatelen = 0 # only valid if newstate != None
 		# start state change handler thread
-		self._q = queue.Queue()
-		self._t = threading.Thread(target=self.queue_consumer)
-		self._t.start()
-	
-	def queue_consumer(self):
-		while True:
-			el = self._q.get()
-			if el is None: return # we are supposed to terminate
-			# handle the state change
-			(oldstate, newstate) = el
-			self.callback(oldstate, newstate)
+		self._callback = ThreadFunction(self.callback)
+		self.stop = self._callback.stop
 	
 	def read(self):
 		curstate = GPIO.input(self._pin)
@@ -42,7 +34,7 @@ class PinWatcher():
 				# we already saw this new state
 				self._newstatelen += 1
 				if self._newstatelen >= self._histlen:
-					self._q.put((self._state, curstate)) # send stuff to the other thread
+					self._callback(self._state, curstate) # send stuff to the other thread
 					self._state = curstate
 					self._newstate = None
 			else:
@@ -52,10 +44,6 @@ class PinWatcher():
 		else:
 			# old state is preserved
 			self._newstate = None
-	
-	def quit(self):
-		self._q.put(None)
-		self._t.join()
 
 class RingWatcher(PinWatcher):
 	def __init__(self):
@@ -96,4 +84,4 @@ try:
 		time.sleep(0.02)
 except KeyboardInterrupt:
 	for pin in pins:
-		pin.quit()
+		pin.stop()
-- 
2.30.2