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-rwxr-xr-xthird_party/libwebrtc/build/clobber.py134
1 files changed, 134 insertions, 0 deletions
diff --git a/third_party/libwebrtc/build/clobber.py b/third_party/libwebrtc/build/clobber.py
new file mode 100755
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+++ b/third_party/libwebrtc/build/clobber.py
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+#!/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('''ninja_required_version = 1.7.2
+
+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())