code.vuplus.com Git - vuplus_webkit/blob - Tools/Scripts/webkitpy/layout_tests/port/http_lock.py

   1 #!/usr/bin/env python
   2 # Copyright (C) 2010 Gabor Rapcsanyi (rgabor@inf.u-szeged.hu), University of Szeged
   3 # Copyright (C) 2010 Andras Becsi (abecsi@inf.u-szeged.hu), University of Szeged
   4 #
   5 # All rights reserved.
   6 #
   7 # Redistribution and use in source and binary forms, with or without
   8 # modification, are permitted provided that the following conditions
   9 # are met:
  10 # 1. Redistributions of source code must retain the above copyright
  11 #    notice, this list of conditions and the following disclaimer.
  12 # 2. Redistributions in binary form must reproduce the above copyright
  13 #    notice, this list of conditions and the following disclaimer in the
  14 #    documentation and/or other materials provided with the distribution.
  15 #
  16 # THIS SOFTWARE IS PROVIDED BY UNIVERSITY OF SZEGED ``AS IS'' AND ANY
  17 # EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  19 # PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL UNIVERSITY OF SZEGED OR
  20 # CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  21 # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  22 # PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  23 # PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  24 # OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27
  28 """This class helps to block NRWT threads when more NRWTs run
  29 http and websocket tests in a same time."""
  30
  31 import logging
  32 import os
  33 import sys
  34 import tempfile
  35 import time
  36
  37 from webkitpy.common.system.executive import Executive
  38 from webkitpy.common.system.file_lock import FileLock
  39 from webkitpy.common.system.filesystem import FileSystem
  40
  41
  42 _log = logging.getLogger(__name__)
  43
  44
  45 class HttpLock(object):
  46     def __init__(self, lock_path, lock_file_prefix="WebKitHttpd.lock.", guard_lock="WebKit.lock", filesystem=None, executive=None):
  47         self._executive = executive or Executive()
  48         self._filesystem = filesystem or FileSystem()
  49         self._lock_path = lock_path
  50         if not self._lock_path:
  51             # FIXME: FileSystem should have an accessor for tempdir()
  52             self._lock_path = tempfile.gettempdir()
  53         self._lock_file_prefix = lock_file_prefix
  54         self._lock_file_path_prefix = self._filesystem.join(self._lock_path, self._lock_file_prefix)
  55         self._guard_lock_file = self._filesystem.join(self._lock_path, guard_lock)
  56         self._guard_lock = FileLock(self._guard_lock_file)
  57         self._process_lock_file_name = ""
  58
  59     def cleanup_http_lock(self):
  60         """Delete the lock file if exists."""
  61         if self._filesystem.exists(self._process_lock_file_name):
  62             _log.debug("Removing lock file: %s" % self._process_lock_file_name)
  63             self._filesystem.remove(self._process_lock_file_name)
  64
  65     def _extract_lock_number(self, lock_file_name):
  66         """Return the lock number from lock file."""
  67         prefix_length = len(self._lock_file_path_prefix)
  68         return int(lock_file_name[prefix_length:])
  69
  70     def _lock_file_list(self):
  71         """Return the list of lock files sequentially."""
  72         lock_list = self._filesystem.glob(self._lock_file_path_prefix + '*')
  73         lock_list.sort(key=self._extract_lock_number)
  74         return lock_list
  75
  76     def _next_lock_number(self):
  77         """Return the next available lock number."""
  78         lock_list = self._lock_file_list()
  79         if not lock_list:
  80             return 0
  81         return self._extract_lock_number(lock_list[-1]) + 1
  82
  83     def _current_lock_pid(self):
  84         """Return with the current lock pid. If the lock is not valid
  85         it deletes the lock file."""
  86         lock_list = self._lock_file_list()
  87         if not lock_list:
  88             _log.debug("No lock file list")
  89             return
  90         try:
  91             current_pid = self._filesystem.read_text_file(lock_list[0])
  92             if not (current_pid and self._executive.check_running_pid(int(current_pid))):
  93                 _log.debug("Removing stuck lock file: %s" % lock_list[0])
  94                 self._filesystem.remove(lock_list[0])
  95                 return
  96         except IOError, e:
  97             _log.debug("IOError: %s" % e)
  98             return
  99         except OSError, e:
 100             _log.debug("OSError: %s" % e)
 101             return
 102         return int(current_pid)
 103
 104     def _create_lock_file(self):
 105         """The lock files are used to schedule the running test sessions in first
 106         come first served order. The guard lock ensures that the lock numbers are
 107         sequential."""
 108         if not self._filesystem.exists(self._lock_path):
 109             _log.debug("Lock directory does not exist: %s" % self._lock_path)
 110             return False
 111
 112         if not self._guard_lock.acquire_lock():
 113             _log.debug("Guard lock timed out!")
 114             return False
 115
 116         self._process_lock_file_name = (self._lock_file_path_prefix + str(self._next_lock_number()))
 117         _log.debug("Creating lock file: %s" % self._process_lock_file_name)
 118         # FIXME: Executive.py should have an accessor for getpid()
 119         self._filesystem.write_text_file(self._process_lock_file_name, str(os.getpid()))
 120         self._guard_lock.release_lock()
 121         return True
 122
 123     def wait_for_httpd_lock(self):
 124         """Create a lock file and wait until it's turn comes. If something goes wrong
 125         it wont do any locking."""
 126         if not self._create_lock_file():
 127             _log.debug("Warning, http locking failed!")
 128             return
 129
 130         # FIXME: This can hang forever!
 131         while self._current_lock_pid() != os.getpid():
 132             time.sleep(1)
 133
 134         _log.debug("HTTP lock acquired")