bin/fetch-gn

#!/usr/bin/env python3

# Copyright 2016 Google Inc.
#
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import os
import platform
import shutil
import stat
import sys
import tempfile
import zipfile

from urllib.request import urlopen

os.chdir(os.path.join(os.path.dirname(__file__), os.pardir))

gnzip = os.path.join(tempfile.mkdtemp(), 'gn.zip')
with open(gnzip, 'wb') as f:
  OS  = {'darwin': 'mac', 'linux': 'linux', 'linux2': 'linux', 'win32': 'windows'}[sys.platform]
  cpu = {'aarch64': 'arm64', 'amd64': 'amd64', 'arm64': 'arm64', 'x86_64': 'amd64'}[platform.machine().lower()]

  rev = 'b2afae122eeb6ce09c52d63f67dc53fc517dbdc8'
  url = 'https://chrome-infra-packages.appspot.com/dl/gn/gn/{}-{}/+/git_revision:{}'.format(
          OS,cpu,rev)
  f.write(urlopen(url).read())

gn_filename = 'gn.exe' if 'win32' in sys.platform else 'gn'
with zipfile.ZipFile(gnzip, 'r') as f:
  f.extract(gn_filename, 'bin')

gn_path = os.path.join('bin', gn_filename)

os.chmod(gn_path,
         stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR |
         stat.S_IRGRP                | stat.S_IXGRP |
         stat.S_IROTH                | stat.S_IXOTH )

# We'll also copy to a path that depot_tools' GN wrapper will expect to find the binary.
depot_tools_gn_dir = os.path.join('third_party', 'gn')
os.makedirs(depot_tools_gn_dir, exist_ok=True)
shutil.copy(gn_path, os.path.join(depot_tools_gn_dir, gn_filename))