build/android/pylib/device/device_blacklist.py

   1 # Copyright 2014 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import json
   6 import os
   7 import threading
   8
   9 from pylib import constants
  10 _BLACKLIST_JSON = os.path.join(
  11     constants.DIR_SOURCE_ROOT,
  12     os.environ.get('CHROMIUM_OUT_DIR', 'out'),
  13     'bad_devices.json')
  14
  15 # Note that this only protects against concurrent accesses to the blacklist
  16 # within a process.
  17 _blacklist_lock = threading.RLock()
  18
  19 def ReadBlacklist():
  20   """Reads the blacklist from the _BLACKLIST_JSON file.
  21
  22   Returns:
  23     A list containing bad devices.
  24   """
  25   with _blacklist_lock:
  26     if not os.path.exists(_BLACKLIST_JSON):
  27       return []
  28
  29     with open(_BLACKLIST_JSON, 'r') as f:
  30       return json.load(f)
  31
  32
  33 def WriteBlacklist(blacklist):
  34   """Writes the provided blacklist to the _BLACKLIST_JSON file.
  35
  36   Args:
  37     blacklist: list of bad devices to write to the _BLACKLIST_JSON file.
  38   """
  39   with _blacklist_lock:
  40     with open(_BLACKLIST_JSON, 'w') as f:
  41       json.dump(list(set(blacklist)), f)
  42
  43
  44 def ExtendBlacklist(devices):
  45   """Adds devices to _BLACKLIST_JSON file.
  46
  47   Args:
  48     devices: list of bad devices to be added to the _BLACKLIST_JSON file.
  49   """
  50   with _blacklist_lock:
  51     blacklist = ReadBlacklist()
  52     blacklist.extend(devices)
  53     WriteBlacklist(blacklist)
  54
  55
  56 def ResetBlacklist():
  57   """Erases the _BLACKLIST_JSON file if it exists."""
  58   with _blacklist_lock:
  59     if os.path.exists(_BLACKLIST_JSON):
  60       os.remove(_BLACKLIST_JSON)
  61