#!/usr/bin/python
#
# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Recover duts.

This module runs at system startup on Chromium OS test images. It runs through
a set of hooks to keep a DUT from being bricked without manual intervention.
Example hook:
  Check to see if ethernet is connected. If its not, unload and reload the
    ethernet driver.
"""

import logging
import os
import subprocess
import time

from logging import handlers

LOGGING_SUBDIR = '/var/log/recover_duts'
LOG_FILENAME = 'recover_duts.log'
LOGGING_FORMAT = '%(asctime)s - %(levelname)s - %(message)s'
LONG_REBOOT_DELAY = 300
SLEEP_DELAY = 600
LOG_FILE_BACKUP_COUNT = 10
LOG_FILE_SIZE = 1024 * 5000 # 5000 KB


def _setup_logging(log_file):
  """Setup logging.

  Args:
    log_file: path to log file.
  """
  log_formatter = logging.Formatter(LOGGING_FORMAT)
  handler = handlers.RotatingFileHandler(
      filename=log_file, maxBytes=LOG_FILE_SIZE,
      backupCount=LOG_FILE_BACKUP_COUNT)
  handler.setFormatter(log_formatter)
  logger = logging.getLogger()
  log_level = logging.DEBUG
  logger.setLevel(log_level)
  logger.addHandler(handler)

def main():
  if not os.path.isdir(LOGGING_SUBDIR):
    os.makedirs(LOGGING_SUBDIR)

  log_file = os.path.join(LOGGING_SUBDIR, LOG_FILENAME)
  _setup_logging(log_file)
  hooks_dir = os.path.join(os.path.dirname(__file__), 'hooks')

  # Additional sleep as networking not be up in the case of a long reboot.
  time.sleep(LONG_REBOOT_DELAY)
  try:
    while True:
      for script in os.listdir(hooks_dir):
        script = os.path.join(hooks_dir, script)
        if os.path.isfile(script) and script.endswith('.hook'):
          logging.debug('Running hook: %s', script)
          popen = subprocess.Popen([script], stdout=subprocess.PIPE,
                                   stderr=subprocess.STDOUT)
          output = popen.communicate()[0]
          if popen.returncode == 0:
            logging.debug('Running of %s succeeded with output:\n%s', script,
                          output)
          else:
            logging.warn('Running of %s failed with output:\n%s', script,
                         output)
      time.sleep(SLEEP_DELAY)

  except Exception as e:
    # Since this is run from an upstart job we want to ensure we log this into
    # our log file before dying.
    logging.fatal(str(e))
    raise


if __name__ == '__main__':
  main()