| #!/usr/bin/env python | 
 |  | 
 | # 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 hashlib | 
 | import os | 
 | import shutil | 
 | import stat | 
 | import sys | 
 | import urllib2 | 
 |  | 
 | os.chdir(os.path.join(os.path.dirname(__file__), os.pardir)) | 
 |  | 
 | dst = 'bin/gn.exe' if 'win32' in sys.platform else 'bin/gn' | 
 |  | 
 | sha1 = '2f27ff0b6118e5886df976da5effa6003d19d1ce' if 'linux'  in sys.platform else \ | 
 |        '9be792dd9010ce303a9c3a497a67bcc5ac8c7666' if 'darwin' in sys.platform else \ | 
 |        'eb69be2d984b4df60a8c21f598135991f0ad1742'  # Windows | 
 |  | 
 | def sha1_of_file(path): | 
 |   h = hashlib.sha1() | 
 |   if os.path.isfile(path): | 
 |     with open(path, 'rb') as f: | 
 |       h.update(f.read()) | 
 |   return h.hexdigest() | 
 |  | 
 | if sha1_of_file(dst) != sha1: | 
 |   with open(dst, 'wb') as f: | 
 |     f.write(urllib2.urlopen('https://chromium-gn.storage-download.googleapis.com/' + sha1).read()) | 
 |  | 
 |   os.chmod(dst, 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. | 
 | copy_path = 'buildtools/linux64/gn' if 'linux'  in sys.platform else \ | 
 |             'buildtools/mac/gn'     if 'darwin' in sys.platform else \ | 
 |             'buildtools/win/gn.exe' | 
 | if os.path.isdir(os.path.dirname(copy_path)): | 
 |   shutil.copy(dst, copy_path) |