blob: fbda4bfdcdcd43669a8ae3f90417cd9bd6210f9c [file] [log] [blame]
#!/usr/bin/env python
#
# Copyright 2007 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""A simple line-oriented "tee"."""
import collections
import threading
class Tee(threading.Thread):
"""A simple line-oriented "tee".
This class connects two file-like objects, piping the output of one to the
input of the other, and buffering the last 100 lines.
"""
_MAX_LINES = 100
def __init__(self, in_f, out_f):
threading.Thread.__init__(self, name='Tee')
self.__in = in_f
self.__out = out_f
self.__deque = collections.deque('', Tee._MAX_LINES)
def run(self):
while True:
line = self.__in.readline()
if not line:
break
self.__out.write(line)
self.__out.flush()
self.__deque.append(line)
def get_buf(self):
return ''.join(self.__deque)