diff options
Diffstat (limited to 'third_party/libwebrtc/build/landmines.py')
| -rwxr-xr-x | third_party/libwebrtc/build/landmines.py | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/third_party/libwebrtc/build/landmines.py b/third_party/libwebrtc/build/landmines.py new file mode 100755 index 0000000000..f5adf80f92 --- /dev/null +++ b/third_party/libwebrtc/build/landmines.py @@ -0,0 +1,151 @@ +#!/usr/bin/env python +# 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. + +""" +This script runs every gclient runhooks as the first hook (See DEPS). If it +detects that the build should be clobbered, it will delete the contents of the +build directory. + +A landmine is tripped when a builder checks out a different revision, and the +diff between the new landmines and the old ones is non-null. At this point, the +build is clobbered. + +Before adding or changing a landmine consider the consequences of doing so. +Doing so will wipe out every output directory on every Chrome developer's +machine. This can be particularly problematic on Windows where the directory +deletion may well fail (locked files, command prompt in the directory, etc.), +and generated .sln and .vcxproj files will be deleted. + +This output directory deletion will be repeated when going back and forth across +the change that added the landmine, adding to the cost. There are usually less +troublesome alternatives. +""" + +import difflib +import errno +import logging +import optparse +import os +import sys +import subprocess +import time + +import clobber +import landmine_utils + + +def get_build_dir(src_dir): + r""" + Returns the absolute path to the directory containing the build directories. + Examples: + 'C:\src\out' + '/b/s/w/ir/cache/builder/src/out' + """ + if 'CHROMIUM_OUT_DIR' in os.environ: + output_dir = os.environ.get('CHROMIUM_OUT_DIR').strip() + if not output_dir: + raise Error('CHROMIUM_OUT_DIR environment variable is set but blank!') + else: + output_dir = 'out' + return os.path.abspath(os.path.join(src_dir, output_dir)) + + +def clobber_if_necessary(new_landmines, src_dir, landmines_path): + """Does the work of setting, planting, and triggering landmines.""" + out_dir = get_build_dir(src_dir) + try: + os.makedirs(out_dir) + except OSError as e: + if e.errno == errno.EEXIST: + pass + + if os.path.exists(landmines_path): + with open(landmines_path, 'r') as f: + old_landmines = f.readlines() + if old_landmines != new_landmines: + old_date = time.ctime(os.stat(landmines_path).st_ctime) + diff = difflib.unified_diff(old_landmines, new_landmines, + fromfile='old_landmines', tofile='new_landmines', + fromfiledate=old_date, tofiledate=time.ctime(), n=0) + sys.stdout.write('Clobbering due to:\n') + sys.stdout.writelines(diff) + sys.stdout.flush() + + clobber.clobber(out_dir) + + # Save current set of landmines for next time. + with open(landmines_path, 'w') as f: + f.writelines(new_landmines) + + +def process_options(): + """Returns an options object containing the configuration for this script.""" + parser = optparse.OptionParser() + parser.add_option( + '-s', '--landmine-scripts', action='append', + help='Path to the script which emits landmines to stdout. The target ' + 'is passed to this script via option -t. Note that an extra ' + 'script can be specified via an env var EXTRA_LANDMINES_SCRIPT.') + parser.add_option('-d', '--src-dir', + help='Path of the source root dir. Overrides the default location of the ' + 'source root dir when calculating the build directory.') + parser.add_option( + '-l', + '--landmines-path', + help='Path to the landmines file to use (defaults to .landmines)') + parser.add_option('-v', '--verbose', action='store_true', + default=('LANDMINES_VERBOSE' in os.environ), + help=('Emit some extra debugging information (default off). This option ' + 'is also enabled by the presence of a LANDMINES_VERBOSE environment ' + 'variable.')) + + options, args = parser.parse_args() + + if args: + parser.error('Unknown arguments %s' % args) + + logging.basicConfig( + level=logging.DEBUG if options.verbose else logging.ERROR) + + if options.src_dir: + if not os.path.isdir(options.src_dir): + parser.error('Cannot find source root dir at %s' % options.src_dir) + logging.debug('Overriding source root dir. Using: %s', options.src_dir) + else: + options.src_dir = \ + os.path.dirname(os.path.dirname(os.path.realpath(__file__))) + + if not options.landmine_scripts: + options.landmine_scripts = [os.path.join(options.src_dir, 'build', + 'get_landmines.py')] + + extra_script = os.environ.get('EXTRA_LANDMINES_SCRIPT') + if extra_script: + options.landmine_scripts += [extra_script] + + return options + + +def main(): + options = process_options() + + landmines = [] + for s in options.landmine_scripts: + proc = subprocess.Popen([sys.executable, s], stdout=subprocess.PIPE, + universal_newlines=True) + output, _ = proc.communicate() + landmines.extend([('%s\n' % l.strip()) for l in output.splitlines()]) + if options.landmines_path: + landmines_path = options.landmines_path + else: + landmines_path = os.path.join(options.src_dir, '.landmines') + clobber_if_necessary(landmines, options.src_dir, + os.path.normpath(landmines_path)) + + return 0 + + +if __name__ == '__main__': + sys.exit(main()) |