| #!/usr/bin/env python |
| # Copyright 2015 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 provides methods for clobbering build directories.""" |
| |
| import argparse |
| import os |
| import shutil |
| import subprocess |
| import sys |
| |
| |
| def extract_gn_build_commands(build_ninja_file): |
| """Extracts from a build.ninja the commands to run GN. |
| |
| The commands to run GN are the gn rule and build.ninja build step at the |
| top of the build.ninja file. We want to keep these when deleting GN builds |
| since we want to preserve the command-line flags to GN. |
| |
| On error, returns the empty string.""" |
| result = "" |
| with open(build_ninja_file, 'r') as f: |
| # Read until the third blank line. The first thing GN writes to the file |
| # is "ninja_required_version = x.y.z", then the "rule gn" and the third |
| # is the section for "build build.ninja", separated by blank lines. |
| num_blank_lines = 0 |
| while num_blank_lines < 3: |
| line = f.readline() |
| if len(line) == 0: |
| return '' # Unexpected EOF. |
| result += line |
| if line[0] == '\n': |
| num_blank_lines = num_blank_lines + 1 |
| return result |
| |
| |
| def delete_dir(build_dir): |
| if os.path.islink(build_dir): |
| return |
| # For unknown reasons (anti-virus?) rmtree of Chromium build directories |
| # often fails on Windows. |
| if sys.platform.startswith('win'): |
| subprocess.check_call(['rmdir', '/s', '/q', build_dir], shell=True) |
| else: |
| shutil.rmtree(build_dir) |
| |
| |
| def delete_build_dir(build_dir): |
| # GN writes a build.ninja.d file. Note that not all GN builds have args.gn. |
| build_ninja_d_file = os.path.join(build_dir, 'build.ninja.d') |
| if not os.path.exists(build_ninja_d_file): |
| delete_dir(build_dir) |
| return |
| |
| # GN builds aren't automatically regenerated when you sync. To avoid |
| # messing with the GN workflow, erase everything but the args file, and |
| # write a dummy build.ninja file that will automatically rerun GN the next |
| # time Ninja is run. |
| build_ninja_file = os.path.join(build_dir, 'build.ninja') |
| build_commands = extract_gn_build_commands(build_ninja_file) |
| |
| try: |
| gn_args_file = os.path.join(build_dir, 'args.gn') |
| with open(gn_args_file, 'r') as f: |
| args_contents = f.read() |
| except IOError: |
| args_contents = '' |
| |
| e = None |
| try: |
| # delete_dir and os.mkdir() may fail, such as when chrome.exe is running, |
| # and we still want to restore args.gn/build.ninja/build.ninja.d, so catch |
| # the exception and rethrow it later. |
| delete_dir(build_dir) |
| os.mkdir(build_dir) |
| except Exception as e: |
| pass |
| |
| # Put back the args file (if any). |
| if args_contents != '': |
| with open(gn_args_file, 'w') as f: |
| f.write(args_contents) |
| |
| # Write the build.ninja file sufficiently to regenerate itself. |
| with open(os.path.join(build_dir, 'build.ninja'), 'w') as f: |
| if build_commands != '': |
| f.write(build_commands) |
| else: |
| # Couldn't parse the build.ninja file, write a default thing. |
| f.write('''rule gn |
| command = gn -q gen //out/%s/ |
| description = Regenerating ninja files |
| |
| build build.ninja: gn |
| generator = 1 |
| depfile = build.ninja.d |
| ''' % (os.path.split(build_dir)[1])) |
| |
| # Write a .d file for the build which references a nonexistant file. This |
| # will make Ninja always mark the build as dirty. |
| with open(build_ninja_d_file, 'w') as f: |
| f.write('build.ninja: nonexistant_file.gn\n') |
| |
| if e: |
| # Rethrow the exception we caught earlier. |
| raise e |
| |
| def clobber(out_dir): |
| """Clobber contents of build directory. |
| |
| Don't delete the directory itself: some checkouts have the build directory |
| mounted.""" |
| for f in os.listdir(out_dir): |
| path = os.path.join(out_dir, f) |
| if os.path.isfile(path): |
| os.unlink(path) |
| elif os.path.isdir(path): |
| delete_build_dir(path) |
| |
| |
| def main(): |
| parser = argparse.ArgumentParser() |
| parser.add_argument('out_dir', help='The output directory to clobber') |
| args = parser.parse_args() |
| clobber(args.out_dir) |
| return 0 |
| |
| |
| if __name__ == '__main__': |
| sys.exit(main()) |