From: Ed Page <eopage@byu.net>
Date: Fri, 26 Mar 2010 12:00:51 +0000 (-0500)
Subject: Adding support for coroutines for async ops through trampolines
X-Git-Url: http://git.maemo.org/git/?p=theonering;a=commitdiff_plain;h=887113c5927f329599cc7044c7b689d1134f0dac

Adding support for coroutines for async ops through trampolines
---

diff --git a/src/util/go_utils.py b/src/util/go_utils.py
index b3682ba..38e20c2 100644
--- a/src/util/go_utils.py
+++ b/src/util/go_utils.py
@@ -158,14 +158,17 @@ class AsyncPool(object):
 		self.__workQueue.put(task)
 
 	@misc.log_exception(_moduleLogger)
-	def __trampoline_callback(self, callback, result):
-		if self.__isRunning:
-			try:
-				callback(result)
-			except Exception:
-				pass
-		else:
-			_moduleLogger.info("Blocked call to %r" % (callback, ))
+	def __trampoline_callback(self, on_success, on_error, isError, result):
+		if not self.__isRunning:
+			if isError:
+				_moduleLogger.error("Masking: %s" % (result, ))
+			isError = True
+			result = StopIteration("Cancelling all callbacks")
+		callback = on_success if not isError else on_error
+		try:
+			callback(result)
+		except Exception:
+			pass
 		return False
 
 	@misc.log_exception(_moduleLogger)
@@ -184,8 +187,41 @@ class AsyncPool(object):
 				isError = True
 			self.__workQueue.task_done()
 
-			callback = on_success if not isError else on_error
-			gobject.idle_add(self.__trampoline_callback, callback, result)
+			gobject.idle_add(self.__trampoline_callback, on_success, on_error, isError, result)
+
+
+class LinearExecution(object):
+
+	def __init__(self, func):
+		self._func = func
+		self._run = None
+
+	def start(self, *args, **kwds):
+		assert self._run is None
+		kwds["on_success"] = self.on_success
+		kwds["on_error"] = self.on_error
+		self._run = self._func(*args, **kwds)
+		trampoline, args, kwds = self._run.send(None) # priming the function
+		trampoline(*args, **kwds)
+
+	@misc.log_exception(_moduleLogger)
+	def on_success(self, *args, **kwds):
+		assert not kwds
+		try:
+			trampoline, args, kwds = self._run.send(args)
+		except StopIteration, e:
+			pass
+		else:
+			trampoline(*args, **kwds)
+
+	@misc.log_exception(_moduleLogger)
+	def on_error(self, error):
+		try:
+			trampoline, args, kwds = self._run.throw(error)
+		except StopIteration, e:
+			pass
+		else:
+			trampoline(*args, **kwds)
 
 
 def throttled(minDelay, queue):