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#

#

# Copyright (C) 2009 Google Inc.

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program 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

# General Public License for more details.

#

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

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

# 02110-1301, USA.

"""Asynchronous pyinotify implementation"""

import pyinotify

import asyncore

class AsyncNotifier(asyncore.file_dispatcher):

  """An asyncore dispatcher for inotify events.

  """

  def __init__(self, watch_manager,

               default_proc_fun=None,

               map=None):

    """

    Constructor for AsyncNotifier, a special asyncore file_dispatcher that

    actually wraps a pyinotify Notifier, making it asyncronous.

    """

    if default_proc_fun is None:

      default_proc_fun=pyinotify.ProcessEvent()

    self.notifier = pyinotify.Notifier(watch_manager, default_proc_fun)

    # here we need to steal the file descriptor from the notifier, so we can

    # use it in the global asyncore select, and avoid calling the

    # check_events() function of the notifier (which doesn't allow us to select

    # together with other file descriptors)

    self.fd = self.notifier._fd

    asyncore.file_dispatcher.__init__(self, self.fd, map)

  def handle_read(self):

    self.notifier.read_events()

    self.notifier.process_events()