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 a hook. If it detects that the build should
   8 be clobbered, it will touch the file <build_dir>/.landmine_triggered. The
   9 various build scripts will then check for the presence of this file and clobber
  10 accordingly. The script will also emit the reasons for the clobber to stdout.
  11
  12 A landmine is tripped when a builder checks out a different revision, and the
  13 diff between the new landmines and the old ones is non-null. At this point, the
  14 build is clobbered.
  15 """
  16
  17 import difflib
  18 import gyp_helper
  19 import logging
  20 import optparse
  21 import os
  22 import sys
  23 import subprocess
  24 import time
  25
  26 import landmine_utils
  27
  28
  29 SRC_DIR = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))
  30
  31
  32 def get_target_build_dir(build_tool, target, is_iphone=False):
  33   """
  34   Returns output directory absolute path dependent on build and targets.
  35   Examples:
  36     r'c:\b\build\slave\win\build\src\out\Release'
  37     '/mnt/data/b/build/slave/linux/build/src/out/Debug'
  38     '/b/build/slave/ios_rel_device/build/src/xcodebuild/Release-iphoneos'
  39
  40   Keep this function in sync with tools/build/scripts/slave/compile.py
  41   """
  42   ret = None
  43   if build_tool == 'xcode':
  44     ret = os.path.join(SRC_DIR, 'xcodebuild',
  45         target + ('-iphoneos' if is_iphone else ''))
  46   elif build_tool in ['make', 'ninja', 'ninja-ios']:  # TODO: Remove ninja-ios.
  47     ret = os.path.join(SRC_DIR, 'out', target)
  48   elif build_tool in ['msvs', 'vs', 'ib']:
  49     ret = os.path.join(SRC_DIR, 'build', target)
  50   else:
  51     raise NotImplementedError('Unexpected GYP_GENERATORS (%s)' % build_tool)
  52   return os.path.abspath(ret)
  53
  54
  55 def set_up_landmines(target, new_landmines):
  56   """Does the work of setting, planting, and triggering landmines."""
  57   out_dir = get_target_build_dir(landmine_utils.builder(), target,
  58                                  landmine_utils.platform() == 'ios')
  59
  60   landmines_path = os.path.join(out_dir, '.landmines')
  61   if not os.path.exists(out_dir):
  62     os.makedirs(out_dir)
  63
  64   if not os.path.exists(landmines_path):
  65     with open(landmines_path, 'w') as f:
  66       f.writelines(new_landmines)
  67   else:
  68     triggered = os.path.join(out_dir, '.landmines_triggered')
  69     with open(landmines_path, 'r') as f:
  70       old_landmines = f.readlines()
  71     if old_landmines != new_landmines:
  72       old_date = time.ctime(os.stat(landmines_path).st_ctime)
  73       diff = difflib.unified_diff(old_landmines, new_landmines,
  74           fromfile='old_landmines', tofile='new_landmines',
  75           fromfiledate=old_date, tofiledate=time.ctime(), n=0)
  76
  77       with open(triggered, 'w') as f:
  78         f.writelines(diff)
  79     elif os.path.exists(triggered):
  80       # Remove false triggered landmines.
  81       os.remove(triggered)
  82
  83
  84 def process_options():
  85   """Returns a list of landmine emitting scripts."""
  86   parser = optparse.OptionParser()
  87   parser.add_option(
  88       '-s', '--landmine-scripts', action='append',
  89       default=[os.path.join(SRC_DIR, 'build', 'get_landmines.py')],
  90       help='Path to the script which emits landmines to stdout. The target '
  91            'is passed to this script via option -t. Note that an extra '
  92            'script can be specified via an env var EXTRA_LANDMINES_SCRIPT.')
  93   parser.add_option('-v', '--verbose', action='store_true',
  94       default=('LANDMINES_VERBOSE' in os.environ),
  95       help=('Emit some extra debugging information (default off). This option '
  96           'is also enabled by the presence of a LANDMINES_VERBOSE environment '
  97           'variable.'))
  98
  99   options, args = parser.parse_args()
 100
 101   if args:
 102     parser.error('Unknown arguments %s' % args)
 103
 104   logging.basicConfig(
 105       level=logging.DEBUG if options.verbose else logging.ERROR)
 106
 107   extra_script = os.environ.get('EXTRA_LANDMINES_SCRIPT')
 108   if extra_script:
 109     return options.landmine_scripts + [extra_script]
 110   else:
 111     return options.landmine_scripts
 112
 113
 114 def main():
 115   landmine_scripts = process_options()
 116   gyp_helper.apply_chromium_gyp_env()
 117
 118   for target in ('Debug', 'Release', 'Debug_x64', 'Release_x64'):
 119     landmines = []
 120     for s in landmine_scripts:
 121       proc = subprocess.Popen([sys.executable, s, '-t', target],
 122                               stdout=subprocess.PIPE)
 123       output, _ = proc.communicate()
 124       landmines.extend([('%s\n' % l.strip()) for l in output.splitlines()])
 125     set_up_landmines(target, landmines)
 126
 127   return 0
 128
 129
 130 if __name__ == '__main__':
 131   sys.exit(main())