Source code for models.DataQueue

#
# TI Voxel Viewer component.
#
# Copyright (c) 2014 Texas Instruments Inc.
#

from collections import deque
from threading import Condition

import numpy as np

class DataQueue(object):
  
  def __init__(self, maxlen = 3):
    self.queue = deque(maxlen = maxlen)
    self.maxlen = maxlen
    self.condition = Condition()

  def _put(self, item):
    self.queue.append(item)

  def put(self, item):
    self.condition.acquire()
    self._put(item)
    self.condition.notify()
    self.condition.release()

  def _get(self):
    return self.queue.popleft()

  def get(self, timeout = None):
    self.condition.acquire()
    
    while not len(self.queue):
      self.condition.wait(timeout)
      if timeout is not None and not len(self.queue): # timed out?
        self.condition.release()
        return None

    item = self._get()

    self.condition.release()
    
    return item

  def tryGet(self):
    self.condition.acquire()

    if len(self.queue):
      item = self._get()
    else:
      item = None
    self.condition.release()

    return item

  def clear(self):
    self.queue.clear()