build/landmines.py

   1 #!/usr/bin/env python
   2 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """
   7 This script runs every build as the first hook (See DEPS). If it detects that
   8 the build should be clobbered, it will delete the contents of the build
   9 directory.
  10
  11 A landmine is tripped when a builder checks out a different revision, and the
  12 diff between the new landmines and the old ones is non-null. At this point, the
  13 build is clobbered.
  14 """
  15
  16 import difflib
  17 import errno
  18 import gyp_environment
  19 import logging
  20 import optparse
  21 import os
  22 import sys
  23 import subprocess
  24 import time
  25
  26 import clobber
  27 import landmine_utils
  28
  29
  30 SRC_DIR = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
  31
  32
  33 def get_build_dir(build_tool, is_iphone=False):
  34   """
  35   Returns output directory absolute path dependent on build and targets.
  36   Examples:
  37     r'c:\b\build\slave\win\build\src\out'
  38     '/mnt/data/b/build/slave/linux/build/src/out'
  39     '/b/build/slave/ios_rel_device/build/src/xcodebuild'
  40
  41   Keep this function in sync with tools/build/scripts/slave/compile.py
  42   """
  43   ret = None
  44   if build_tool == 'xcode':
  45     ret = os.path.join(SRC_DIR, 'xcodebuild')
  46   elif build_tool in ['make', 'ninja', 'ninja-ios']:  # TODO: Remove ninja-ios.
  47     if 'CHROMIUM_OUT_DIR' in os.environ:
  48       output_dir = os.environ.get('CHROMIUM_OUT_DIR').strip()
  49       if not output_dir:
  50         raise Error('CHROMIUM_OUT_DIR environment variable is set but blank!')
  51     else:
  52       output_dir = landmine_utils.gyp_generator_flags().get('output_dir', 'out')
  53     ret = os.path.join(SRC_DIR, output_dir)
  54   else:
  55     raise NotImplementedError('Unexpected GYP_GENERATORS (%s)' % build_tool)
  56   return os.path.abspath(ret)
  57
  58
  59 def clobber_if_necessary(new_landmines):
  60   """Does the work of setting, planting, and triggering landmines."""
  61   out_dir = get_build_dir(landmine_utils.builder())
  62   landmines_path = os.path.normpath(os.path.join(out_dir, '..', '.landmines'))
  63   try:
  64     os.makedirs(out_dir)
  65   except OSError as e:
  66     if e.errno == errno.EEXIST:
  67       pass
  68
  69   if os.path.exists(landmines_path):
  70     with open(landmines_path, 'r') as f:
  71       old_landmines = f.readlines()
  72     if old_landmines != new_landmines:
  73       old_date = time.ctime(os.stat(landmines_path).st_ctime)
  74       diff = difflib.unified_diff(old_landmines, new_landmines,
  75           fromfile='old_landmines', tofile='new_landmines',
  76           fromfiledate=old_date, tofiledate=time.ctime(), n=0)
  77       sys.stdout.write('Clobbering due to:\n')
  78       sys.stdout.writelines(diff)
  79
  80       clobber.clobber(out_dir)
  81
  82   # Save current set of landmines for next time.
  83   with open(landmines_path, 'w') as f:
  84     f.writelines(new_landmines)
  85
  86
  87 def process_options():
  88   """Returns a list of landmine emitting scripts."""
  89   parser = optparse.OptionParser()
  90   parser.add_option(
  91       '-s', '--landmine-scripts', action='append',
  92       default=[os.path.join(SRC_DIR, 'build', 'get_landmines.py')],
  93       help='Path to the script which emits landmines to stdout. The target '
  94            'is passed to this script via option -t. Note that an extra '
  95            'script can be specified via an env var EXTRA_LANDMINES_SCRIPT.')
  96   parser.add_option('-v', '--verbose', action='store_true',
  97       default=('LANDMINES_VERBOSE' in os.environ),
  98       help=('Emit some extra debugging information (default off). This option '
  99           'is also enabled by the presence of a LANDMINES_VERBOSE environment '
 100           'variable.'))
 101
 102   options, args = parser.parse_args()
 103
 104   if args:
 105     parser.error('Unknown arguments %s' % args)
 106
 107   logging.basicConfig(
 108       level=logging.DEBUG if options.verbose else logging.ERROR)
 109
 110   extra_script = os.environ.get('EXTRA_LANDMINES_SCRIPT')
 111   if extra_script:
 112     return options.landmine_scripts + [extra_script]
 113   else:
 114     return options.landmine_scripts
 115
 116
 117 def main():
 118   landmine_scripts = process_options()
 119
 120   if landmine_utils.builder() in ('dump_dependency_json', 'eclipse'):
 121     return 0
 122
 123   gyp_environment.SetEnvironment()
 124
 125   landmines = []
 126   for s in landmine_scripts:
 127     proc = subprocess.Popen([sys.executable, s], stdout=subprocess.PIPE)
 128     output, _ = proc.communicate()
 129     landmines.extend([('%s\n' % l.strip()) for l in output.splitlines()])
 130   clobber_if_necessary(landmines)
 131
 132   return 0
 133
 134
 135 if __name__ == '__main__':
 136   sys.exit(main())