diff options
Diffstat (limited to 'cwp/cr-os/fetch_gn_descs.py')
| -rwxr-xr-x | cwp/cr-os/fetch_gn_descs.py | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/cwp/cr-os/fetch_gn_descs.py b/cwp/cr-os/fetch_gn_descs.py new file mode 100755 index 00000000..60d331c5 --- /dev/null +++ b/cwp/cr-os/fetch_gn_descs.py @@ -0,0 +1,196 @@ +#!/usr/bin/env python3 +# -*- coding: utf-8 -*- +# Copyright 2020 The Chromium OS Authors. All rights reserved. +# Use of this source code is governed by a BSD-style license that can be +# found in the LICENSE file. + +"""Produces a JSON object of `gn desc`'s output for each given arch. + +A full Chromium checkout is required in order to run this script. + +The result is of the form: +{ + "arch1": { + "//gn:target": { + 'configs": ["bar"], + "sources": ["foo"] + } + } +} +""" + +from __future__ import print_function + +import argparse +import json +# pylint: disable=cros-logging-import +import logging +import os +import subprocess +import sys +import tempfile + + +def _find_chromium_root(search_from): + """Finds the chromium root directory from `search_from`.""" + current = search_from + while current != '/': + if os.path.isfile(os.path.join(current, '.gclient')): + return current + current = os.path.dirname(current) + raise ValueError( + "%s doesn't appear to be a Chromium subdirectory" % search_from) + + +def _create_gn_args_for(arch): + """Creates a `gn args` listing for the given architecture.""" + # FIXME(gbiv): is_chromeos_device = True would be nice to support, as well. + # Requires playing nicely with SimpleChrome though, and this should be "close + # enough" for now. + return '\n'.join(( + 'target_os = "chromeos"', + 'target_cpu = "%s"' % arch, + 'is_official_build = true', + 'is_chrome_branded = true', + )) + + +def _parse_gn_desc_output(output): + """Parses the output of `gn desc --format=json`. + + Args: + output: a seekable file containing the JSON output of `gn desc`. + + Returns: + A tuple of (warnings, gn_desc_json). + """ + warnings = [] + desc_json = None + while True: + start_pos = output.tell() + next_line = next(output, None) + if next_line is None: + raise ValueError('No JSON found in the given gn file') + + if next_line.lstrip().startswith('{'): + output.seek(start_pos) + desc_json = json.load(output) + break + + warnings.append(next_line) + + return ''.join(warnings).strip(), desc_json + + +def _run_gn_desc(in_dir, gn_args): + logging.info('Running `gn gen`...') + subprocess.check_call(['gn', 'gen', '.', '--args=' + gn_args], cwd=in_dir) + + logging.info('Running `gn desc`...') + with tempfile.TemporaryFile(mode='r+', encoding='utf-8') as f: + gn_command = ['gn', 'desc', '--format=json', '.', '//*:*'] + exit_code = subprocess.call(gn_command, stdout=f, cwd=in_dir) + f.seek(0) + if exit_code: + logging.error('gn failed; stdout:\n%s', f.read()) + raise subprocess.CalledProcessError(exit_code, gn_command) + warnings, result = _parse_gn_desc_output(f) + + if warnings: + logging.warning('Encountered warning(s) running `gn desc`:\n%s', warnings) + return result + + +def _fix_result(rename_out, out_dir, chromium_root, gn_desc): + """Performs postprocessing on `gn desc` JSON.""" + result = {} + + rel_out = '//' + os.path.relpath(out_dir, os.path.join(chromium_root, 'src')) + rename_out = rename_out if rename_out.endswith('/') else rename_out + '/' + + def fix_source_file(f): + if not f.startswith(rel_out): + return f + return rename_out + f[len(rel_out) + 1:] + + for target, info in gn_desc.items(): + sources = info.get('sources') + configs = info.get('configs') + if not sources or not configs: + continue + + result[target] = { + 'configs': configs, + 'sources': [fix_source_file(f) for f in sources], + } + + return result + + +def main(args): + known_arches = [ + 'arm', + 'arm64', + 'x64', + 'x86', + ] + + parser = argparse.ArgumentParser( + description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter) + parser.add_argument( + 'arch', + nargs='+', + help='Architecture(s) to fetch `gn desc`s for. ' + 'Supported ones are %s' % known_arches) + parser.add_argument( + '--output', required=True, help='File to write results to.') + parser.add_argument( + '--chromium_out_dir', + required=True, + help='Chromium out/ directory for us to use. This directory will ' + 'be clobbered by this script.') + parser.add_argument( + '--rename_out', + default='//out', + help='Directory to rename files in --chromium_out_dir to. ' + 'Default: %(default)s') + opts = parser.parse_args(args) + + logging.basicConfig( + format='%(asctime)s: %(levelname)s: %(filename)s:%(lineno)d: %(message)s', + level=logging.INFO, + ) + + arches = opts.arch + rename_out = opts.rename_out + for arch in arches: + if arch not in known_arches: + parser.error( + 'unknown architecture: %s; try one of %s' % (arch, known_arches)) + + results_file = os.path.realpath(opts.output) + out_dir = os.path.realpath(opts.chromium_out_dir) + chromium_root = _find_chromium_root(out_dir) + + os.makedirs(out_dir, exist_ok=True) + results = {} + for arch in arches: + logging.info('Getting `gn` desc for %s...', arch) + + results[arch] = _fix_result( + rename_out, out_dir, chromium_root, + _run_gn_desc( + in_dir=out_dir, + gn_args=_create_gn_args_for(arch), + )) + + os.makedirs(os.path.dirname(results_file), exist_ok=True) + + results_intermed = results_file + '.tmp' + with open(results_intermed, 'w', encoding='utf-8') as f: + json.dump(results, f) + os.rename(results_intermed, results_file) + + +if __name__ == '__main__': + sys.exit(main(sys.argv[1:])) |