return '...'

            _track.append(id(self))

            r = 'deque(%r, maxlen=%s)' % (list(self), self.maxlen)

            _track.remove(id(self))

            return r

        def __getstate__(self):

            return (tuple(self),)

        def __setstate__(self, s):

            self.__init__(s[0])

        def __hash__(self):

            raise TypeError

        def __copy__(self):

            return self.__class__(self)

        def __deepcopy__(self, memo={}):

            from copy import deepcopy

            result = self.__class__()

            memo[id(self)] = result

            result.__init__(deepcopy(tuple(self), memo))

            return result

stream processor exposing the output data as an iterator fitting to be a

return value passed by a WSGI applicaiton to a WSGI server per PEP 3333.

Copyright (c) 2011  Daniel Dotsenko <dotsa@hotmail.com>

This file is part of git_http_backend.py Project.

git_http_backend.py Project is free software: you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public License as

published by the Free Software Foundation, either version 2.1 of the License,

or (at your option) any later version.

git_http_backend.py Project is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License

along with git_http_backend.py Project.

If not, see <http://www.gnu.org/licenses/>.

'''

import os

import subprocess

import threading

class StreamFeeder(threading.Thread):

    """

    Normal writing into pipe-like is blocking once the buffer is filled.

    This thread allows a thread to seep data from a file-like into a pipe

    without blocking the main thread.

    We close inpipe once the end of the source stream is reached.

    """

    def __init__(self, source):

        super(StreamFeeder, self).__init__()

        self.daemon = True

        filelike = False

        self.bytes = bytes()

        if type(source) in (type(''), bytes, bytearray):  # string-like

            self.bytes = bytes(source)

        else:  # can be either file pointer or file-like

            if type(source) in (int, long):  # file pointer it is

                ## converting file descriptor (int) stdin into file-like

                try:

                    source = os.fdopen(source, 'rb', 16384)

                except Exception:

                    pass

            # let's see if source is file-like by now

            s = self.source

            b = s.read(4096)

            while b:

                os.write(t, b)

                b = s.read(4096)

        os.close(t)

    @property

    def output(self):

        return self.readiface

class InputStreamChunker(threading.Thread):

    def __init__(self, source, target, buffer_size, chunk_size):

        super(InputStreamChunker, self).__init__()

        self.daemon = True  # die die die.

        self.source = source

        self.target = target

        self.chunk_count_max = int(buffer_size / chunk_size) + 1

        self.chunk_size = chunk_size

        self.data_added.clear()

        self.keep_reading.set()

        self.EOF.clear()

        self.go.set()

    def stop(self):

        self.go.clear()

        self.EOF.set()

        try:

            # this is not proper, but is done to force the reader thread let

            # go of the input because, if successful, .close() will send EOF

            # down the pipe.

            self.source.close()

        except:

            pass

    def run(self):

        s = self.source

        t = self.target

        cs = self.chunk_size

        ccm = self.chunk_count_max

        kr = self.keep_reading

        da = self.data_added

        go = self.go

        b = s.read(cs)

        while b and go.is_set():

            if len(t) > ccm: