Support HTTP test-server based net unit tests on Android.

build/android/pylib/ports.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-"""Functions that deals with local and device ports."""
+"""Functions that deal with local and device ports."""
 
 import contextlib
 import fcntl
 import httplib
 import logging
 import os
 import re
 import socket
 import traceback
 
 import cmd_helper
 import constants
 
 
-#The following two methods are used to allocate the port source for various
-# types of test servers. Because some net relates tests can be run on shards
-# at same time, it's important to have a mechanism to allocate the port process
-# safe. In here, we implement the safe port allocation by leveraging flock.
+# The following two methods are used to allocate the port source for various
+# types of test servers. Because some net-related tests can be run on shards at
+# same time, it's important to have a mechanism to allocate the port
+# process-safe. In here, we implement the safe port allocation by leveraging
+# flock.
 def ResetTestServerPortAllocation():
-  """Reset the port allocation to start from TEST_SERVER_PORT_FIRST.
+  """Resets the port allocation to start from TEST_SERVER_PORT_FIRST.
 
   Returns:
     Returns True if reset successes. Otherwise returns False.
   """
   try:
     with open(constants.TEST_SERVER_PORT_FILE, 'w') as fp:
       fp.write('%d' % constants.TEST_SERVER_PORT_FIRST)
     if os.path.exists(constants.TEST_SERVER_PORT_LOCKFILE):
       os.unlink(constants.TEST_SERVER_PORT_LOCKFILE)
     return True
   except Exception as e:
     logging.error(e)
   return False
 
 
 def AllocateTestServerPort():
-  """Allocate a port incrementally.
+  """Allocates a port incrementally.
 
   Returns:
     Returns a valid port which should be in between TEST_SERVER_PORT_FIRST and
     TEST_SERVER_PORT_LAST. Returning 0 means no more valid port can be used.
   """
   port = 0
   ports_tried = []
   try:
     fp_lock = open(constants.TEST_SERVER_PORT_LOCKFILE, 'w')
     fcntl.flock(fp_lock, fcntl.LOCK_EX)
@@ skipping 30 matching lines @@
   """Checks whether the specified host port is used or not.
 
   Uses -n -P to inhibit the conversion of host/port numbers to host/port names.
 
   Args:
     host_port: Port on host we want to check.
 
   Returns:
     True if the port on host is already used, otherwise returns False.
   """
-  port_info = '(127\.0\.0\.1)|(localhost)\:%d' % host_port
-  # TODO(jnd): Find a better way to filter the port.
+  port_info = '(\*)|(127\.0\.0\.1)|(localhost):%d' % host_port
+  # TODO(jnd): Find a better way to filter the port. Note that connecting to the
+  # socket and closing it would leave it in the TIME_WAIT state. Setting
+  # SO_LINGER on it and then closing it makes the Python HTTP server crash.
   re_port = re.compile(port_info, re.MULTILINE)
-  if re_port.findall(cmd_helper.GetCmdOutput(['lsof', '-nPi:%d' % host_port])):
+  if re_port.search(cmd_helper.GetCmdOutput(['lsof', '-nPi:%d' % host_port])):
     return True
   return False
 
 
 def IsDevicePortUsed(adb, device_port, state=''):
   """Checks whether the specified device port is used or not.
 
   Args:
     adb: Instance of AndroidCommands for talking to the device.
     device_port: Port on device we want to check.
     state: String of the specified state. Default is empty string, which
            means any state.
 
   Returns:
     True if the port on device is already used, otherwise returns False.
   """
   base_url = '127.0.0.1:%d' % device_port
   netstat_results = adb.RunShellCommand('netstat', log_result=False)
   for single_connect in netstat_results:
     # Column 3 is the local address which we want to check with.
     connect_results = single_connect.split()
+    if connect_results[0] != 'tcp':
+      continue
+    if len(connect_results) < 6:
+      raise Exception('Unexpected format while parsing netstat line: ' +
+                      single_connect)
     is_state_match = connect_results[5] == state if state else True
     if connect_results[3] == base_url and is_state_match:
       return True
   return False
 
 
 def IsHttpServerConnectable(host, port, tries=3, command='GET', path='/',
                             expected_read='', timeout=2):
   """Checks whether the specified http server is ready to serve request or not.
 
@@ skipping 31 matching lines @@
         client_error = ('Bad response: %s %s version %s\n  ' %
                         (r.status, r.reason, r.version) +
                         '\n  '.join([': '.join(h) for h in r.getheaders()]))
     except (httplib.HTTPException, socket.error) as e:
       # Probably too quick connecting: try again.
       exception_error_msgs = traceback.format_exception_only(type(e), e)
       if exception_error_msgs:
         client_error = ''.join(exception_error_msgs)
   # Only returns last client_error.
   return (False, client_error or 'Timeout')