avoid hard-coding a default value twice

[saartuer.git] / waker.py

diff --git a/waker.py b/waker.py
index 7b212a194f79bdc5398c47e52cf2c2dccf9aa4c0..4898c25ab31c0754f79699c97a0983477a8c23af 100644 (file)
--- a/waker.py
+++ b/waker.py
@@ -1,13 +1,43 @@
 from libtuer import ThreadRepeater
-from statemachine import StateMachine
+from threading import Lock
+
+SLEEP_TIME = 0.5
+
+class ToBeWoken:
+       '''a simple struct storing information about a to-be-woken function'''
+       def __init__(self, f, period, one_shot):
+               self.f = f
+               self.period = period
+               self.time_since_call = 0
+               self.one_shot = one_shot
 
 class Waker():
-       def __init__(self, sm):
-               self._sm = sm
-               self._t = ThreadRepeater(self._wake, 0.5, name="Waker")
+       def __init__(self):
+               self._tobewokens = []
+               self._tobewokens_lock = Lock()
+               self._t = ThreadRepeater(self._wake, SLEEP_TIME, name="Waker")
+       
+       def register(self, f, time, one_shot = False):
+               '''Register a function which is called approximately every <time> seconds (or just once, if one_shot is True). f should return quickly, or it will delay the waker!'''
+               time = max(time//SLEEP_TIME, 1)
+               with self._tobewokens_lock:
+                       self._tobewokens.append(ToBeWoken(f, time, 0, one_shot))
        
        def _wake(self):
-               self._sm.callback(StateMachine.CMD_WAKEUP)
+               with self._tobewokens_lock:
+                       delete = []
+                       # run the functions we ought to run
+                       for tobewoken, idx in zip(self._tobewokens, range(len(self._tobewokens))):
+                               tobewoken.time_since_call += 1
+                               if tobewoken.time_since_call >= tobewoken.period:
+                                       tobewoken.f()
+                                       tobewoken.time_since_call = 0
+                                       if tobewoken.one_shot:
+                                               delete.append(idx)
+                       # delete what we have to delete - in reverse order so the indices stay valid!
+                       delete.reverse()
+                       for idx in delete:
+                               del self._tobewokens[idx]
        
        def stop(self):
                self._t.stop()