From ad74e38512597f26c6137d12b99e591ba2ba0f0e Mon Sep 17 00:00:00 2001
From: Thomas Leonard <talex5@gmail.com>
Date: Thu, 25 Nov 2004 13:43:23 +0000
Subject: [PATCH] Added tasks.InputBlocker, which triggers when an input source
 becomes readable (Thomas Leonard).

git-svn-id: https://rox.svn.sourceforge.net/svnroot/rox/trunk/ROX-Lib2@3724 66de3db3-b00d-0410-b41b-f4738ad19bea
---
 Help/Changes              |  5 +++++
 python/rox/tasks.py       | 27 ++++++++++++++++++++++++-
 tests/python/testtasks.py | 51 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 82 insertions(+), 1 deletion(-)
 create mode 100755 tests/python/testtasks.py

diff --git a/Help/Changes b/Help/Changes
index be9755b..5047804 100644
--- a/Help/Changes
+++ b/Help/Changes
@@ -3,6 +3,11 @@
 			by Thomas Leonard
 			http://rox.sourceforge.net
 
+25-Nov-2004
+~~~~~~~~~~~
+Added tasks.InputBlocker, which triggers when an input source becomes
+readable (Thomas Leonard).
+
 21-Nov-2004
 ~~~~~~~~~~~
 Bugfix: Use only text nodes when getting the tool tip from the Options.xml
diff --git a/python/rox/tasks.py b/python/rox/tasks.py
index 2081735..d59c8d2 100644
--- a/python/rox/tasks.py
+++ b/python/rox/tasks.py
@@ -95,6 +95,11 @@ class Blocker:
 		Blocker. If you override this method, be sure to still
 		call this method with Blocker.add_task(self)!"""
 		self._rox_lib_tasks[task] = True
+	
+	def remove_task(self, task):
+		"""Called by the schedular when a Task that was waiting for
+		this blocker is resumed."""
+		del self._rox_lib_tasks[task]
 
 class IdleBlocker(Blocker):
 	"""An IdleBlocker blocks until a task starts waiting on it, then
@@ -119,6 +124,26 @@ class TimeoutBlocker(Blocker):
 		rox.toplevel_unref()
 		self.trigger()
 
+class InputBlocker(Blocker):
+	"""Triggers when os.read(stream) would not block."""
+	_tag = None
+	_stream = None
+	def __init__(self, stream):
+		Blocker.__init__(self)
+		self._stream = stream
+	
+	def add_task(self, task):
+		Blocker.add_task(self, task)
+		if self._tag is None:
+			self._tag = g.input_add(self._stream, g.gdk.INPUT_READ,
+				lambda src, cond: self.trigger())
+	
+	def remove_task(self, task):
+		Blocker.remove_task(self, task)
+		if not self._rox_lib_tasks:
+			g.input_remove(self._tag)
+			self._tag = None
+
 _idle_blocker = IdleBlocker()
 
 class Task:
@@ -159,7 +184,7 @@ class Task:
 	def _resume(self):
 		# Remove from our blockers' queues
 		for blocker in self._rox_blockers:
-			del blocker._rox_lib_tasks[self]
+			blocker.remove_task(self)
 		# Resume the task
 		try:
 			new_blockers = self.next()
diff --git a/tests/python/testtasks.py b/tests/python/testtasks.py
new file mode 100755
index 0000000..0e044f0
--- /dev/null
+++ b/tests/python/testtasks.py
@@ -0,0 +1,51 @@
+#!/usr/bin/env python2.2
+from __future__ import generators
+import unittest
+import sys
+import os, time
+from os.path import dirname, abspath, join
+
+rox_lib = dirname(dirname(dirname(abspath(sys.argv[0]))))
+sys.path.insert(0, join(rox_lib, 'python'))
+
+from rox import tasks, g
+
+class TestTasks(unittest.TestCase):
+	def testIdleBlocker(self):
+		def run():
+			yield None
+			g.mainquit()
+		tasks.Task(run())
+		g.mainloop()
+
+	def testTimeoutBlocker(self):
+		def run():
+			start = time.time()
+			yield tasks.TimeoutBlocker(0.5)
+			end = time.time()
+			assert end > start + 0.5
+			g.mainquit()
+		tasks.Task(run())
+		g.mainloop()
+	
+	def testInputBlocker(self):
+		readable, writeable = os.pipe()
+		def run():
+			ib = tasks.InputBlocker(readable)
+			tb = tasks.TimeoutBlocker(0.2)
+			yield ib, tb
+			assert not ib.happened
+			assert tb.happened
+			os.write(writeable, "!")
+
+			tb = tasks.TimeoutBlocker(0.2)
+			yield ib, tb
+			assert ib.happened
+			assert not tb.happened
+
+			g.mainquit()
+		tasks.Task(run())
+		g.mainloop()
+
+sys.argv.append('-v')
+unittest.main()
-- 
2.11.4.GIT