| # Copyright (c) 2014 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. |
| |
| import logging |
| import re |
| |
| IW_REMOTE_EVENT_LOG_FILE = '/tmp/iw_event.log' |
| |
| class IwEventLogger(object): |
| """Context enclosing the use of iw event logger.""" |
| def __init__(self, host, command_iw, local_file): |
| self._host = host |
| self._command_iw = command_iw |
| self._local_file = local_file |
| self._pid = None |
| |
| |
| def __enter__(self): |
| return self |
| |
| |
| def __exit__(self, exception, value, traceback): |
| self.stop() |
| |
| |
| @property |
| def local_file(self): |
| """@return string local host path for log file.""" |
| return self._local_file |
| |
| |
| def start(self): |
| """Start event logger. |
| |
| This function will start iw event process in remote host, and redirect |
| output to a temporary file in remote host. |
| |
| """ |
| command = '%s event -t > %s & echo $!' % (self._command_iw, |
| IW_REMOTE_EVENT_LOG_FILE) |
| self._pid = int(self._host.run(command).stdout) |
| |
| |
| def stop(self): |
| """Stop event logger. |
| |
| This function will kill iw event process, and copy the log file from |
| remote to local. |
| |
| """ |
| if self._pid is None: |
| return |
| # Kill iw event process |
| self._host.run('kill %d' % self._pid, ignore_status=True) |
| self._pid = None |
| # Copy iw event log file from remote host |
| self._host.get_file(IW_REMOTE_EVENT_LOG_FILE, self._local_file) |
| logging.info('iw event log saved to %s', self._local_file) |
| |
| |
| def get_association_time(self): |
| """Parse local log file and return association time. |
| |
| This function will parse the iw event log to determine the time it |
| takes from start of scan to being connected. |
| Here are example of lines to be parsed: |
| 1393961008.058711: wlan0 (phy #0): scan started |
| 1393961019.758599: wlan0 (phy #0): connected to 04:f0:21:03:7d:bd |
| |
| @returns float number of seconds it take from start of scan to |
| connected. Return None if unable to determine the time based on |
| the log. |
| |
| """ |
| start_time = None |
| end_time = None |
| # Parse file to figure out the time when scanning started and the time |
| # when client is connected. |
| with open(self._local_file, 'r') as file: |
| for line in file.readlines(): |
| parse_line = re.match('\s*(\d+).(\d+): (\w.*): (\w.*)', line) |
| if parse_line: |
| time_integer = parse_line.group(1) |
| time_decimal = parse_line.group(2) |
| message = parse_line.group(4) |
| time_stamp = float('%s.%s' % (time_integer, time_decimal)) |
| if (message.startswith('scan started') and |
| start_time is None): |
| start_time = time_stamp |
| if message.startswith('connected'): |
| if start_time is None: |
| return None |
| end_time = time_stamp |
| break; |
| else: |
| return None |
| return end_time - start_time |
