teer_ros.py
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00001 # -*- coding: utf-8 -*-
00002 # kate: replace-tabs off; indent-width 4; indent-mode normal
00003 # vim: ts=4:sw=4:noexpandtab
00004 
00005 import sys
00006 import os
00007 core_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'core')
00008 sys.path.append(core_path)
00009 import teer as core
00010 import threading
00011 import rospy
00012 
00013 # ------------------------------------------------------------
00014 #               === Scheduler working with ROS' time and threading ===
00015 # ------------------------------------------------------------
00016 class Scheduler(core.Scheduler):
00017         """ A scheduler supporting multi-threading access and ROS time """
00018         def __init__(self):
00019                 super(Scheduler, self).__init__()
00020                 self.wake_cond = threading.Condition()
00021                 self.running = True
00022                 self.in_timer_count = 0
00023                 def stop_run():
00024                         self.wake_cond.acquire()
00025                         self.running = False
00026                         self.wake_cond.notify()
00027                         self.wake_cond.release()
00028                 rospy.on_shutdown(stop_run)
00029         
00030         # Public API, these functions are safe to be called from within a task or from outside
00031         
00032         def current_time(self):
00033                 return rospy.Time.now().to_sec()
00034         
00035         # Public API, these funtions must be called outside a task
00036         
00037         def run(self):
00038                 self.wake_cond.acquire()
00039                 self.step()
00040                 while not rospy.is_shutdown() and self.running and ((self.in_timer_count != 0) or self.cond_waiting or self.ready):
00041                         self.wake_cond.wait()
00042                         self.step()
00043         
00044         # Protected implementations, these functions can only be called by functions from this object
00045         
00046         def _sleep(self, duration):
00047                 rospy.sleep(duration)
00048         
00049         def _set_timer_callback(self, t, f):
00050                 def timer_callback(event):
00051                         self.wake_cond.acquire()
00052                         self.in_timer_count -= 1
00053                         f()
00054                         self.wake_cond.notify()
00055                         self.wake_cond.release()
00056                 self.in_timer_count += 1
00057                 rospy.Timer(rospy.Duration(t - self.current_time()), timer_callback, True)
00058 
00059 # ------------------------------------------------------------
00060 #        === Conditional Variables working with ROS' threading ===
00061 # ------------------------------------------------------------
00062 class ConditionVariable(core.ConditionVariable):
00063         """ A conditional variable working with ROS' Scheduler """
00064         def __init__(self, initval=None):
00065                 super(ConditionVariable, self).__init__(initval)
00066         def __get__(self, obj, objtype):
00067                 return self.val
00068         def __set__(self, obj, val):
00069                 obj.wake_cond.acquire()
00070                 self.val = val
00071                 self._set_name(type(obj))
00072                 obj._test_conditions(self.myname)
00073                 obj.wake_cond.notify()
00074                 obj.wake_cond.release()
00075 
00076 # ------------------------------------------------------------
00077 #                    === Alias for other objects ===
00078 # ------------------------------------------------------------
00079 
00080 Task = core.Task
00081 Rate = core.Rate
00082 Pass = core.Pass
00083 GetScheduler = core.GetScheduler
00084 WaitTask = core.WaitTask
00085 WaitAllTasks = core.WaitAllTasks
00086 WaitAnyTasks = core.WaitAnyTasks
00087 WaitDuration = core.WaitDuration
00088 WaitCondition = core.WaitCondition
00089 Sleep = core.Sleep


teer_ros
Author(s): St├ęphane Magnenat
autogenerated on Sat Dec 28 2013 16:57:36