git_bootstrap.py: add a switch to controll client bitness

bootstrap/win/git_bootstrap.py

 # Copyright 2016 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.
 
 import argparse
 import fnmatch
 import logging
 import os
 import shutil
 import subprocess
@@ skipping 25 matching lines @@
 
 def clean_up_old_git_installations(git_directory):
   """Removes git installations other than |git_directory|."""
   for entry in fnmatch.filter(os.listdir(ROOT_DIR), 'git-*_bin'):
     full_entry = os.path.join(ROOT_DIR, entry)
     if full_entry != git_directory:
       logging.info('Cleaning up old git installation %r', entry)
       shutil.rmtree(full_entry, ignore_errors=True)
 
 
-def bootstrap_cipd(cipd_directory):
+def bootstrap_cipd(cipd_directory, cipd_platform):
   """Bootstraps CIPD client into |cipd_directory|."""
   _check_call([
       sys.executable,
       os.path.join(ROOT_DIR, 'recipe_modules', 'cipd', 'resources',
                    'bootstrap.py'),
-      '--platform', 'windows-amd64',
+      '--platform', cipd_platform,
       '--dest-directory', cipd_directory
   ])
 
 
 def cipd_install(args, dest_directory, package, version):
   """Installs CIPD |package| at |version| into |dest_directory|."""
   manifest_file = tempfile.mktemp()
   try:
     with open(manifest_file, 'w') as f:
       f.write('%s %s\n' % (package, version))
@@ skipping 33 matching lines @@
       if os.path.relpath(git_directory, ROOT_DIR) not in f.read():
         return True
   if not os.path.exists(os.path.join(
       git_directory, 'etc', 'profile.d', 'python.sh')):
     return True
   return False
 
 
 def install_git(args, git_version, git_directory):
   """Installs |git_version| into |git_directory|."""
+  cipd_platform = 'windows-%s' % ('amd64' if args.bits == 64 else '386')
   if not args.cipd_client:
-    bootstrap_cipd(ROOT_DIR)
+    bootstrap_cipd(ROOT_DIR, cipd_platform)
     args.cipd_client = os.path.join(ROOT_DIR, 'cipd')
   temp_dir = tempfile.mkdtemp()
   try:
     cipd_install(args,
                  temp_dir,
-                 'infra/depot_tools/git_installer/windows-amd64',
+                 'infra/depot_tools/git_installer/%s' % cipd_platform,
                  'v' + git_version.replace('.', '_'))
 
     if not os.path.exists(git_directory):
       os.makedirs(git_directory)
 
     # 7-zip has weird expectations for command-line syntax. Pass it as a string
     # to avoid subprocess module quoting breaking it. Also double-escape
     # backslashes in paths.
     _check_call(' '.join([
       os.path.join(temp_dir, 'git-installer.exe'),
@@ skipping 38 matching lines @@
   # TODO(phajdan.jr): consider replacing the call with python code.
   _check_call([
       'xcopy', '/i', '/q', '/d', '/y',
       os.path.join(ROOT_DIR, 'man', 'html', '*'),
       os.path.join(git_directory, 'mingw64', 'share', 'doc', 'git-doc')],
       stdout=DEVNULL)
 
 
 def main(argv):
   parser = argparse.ArgumentParser()
+  parser.add_argument('--bits', type=int, choices=(32,64), default=64,
+                      help='Bitness of the client to install.')
   parser.add_argument('--cipd-client', help='Path to CIPD client binary.')
   parser.add_argument('--cipd-cache-directory',
                       help='Path to CIPD cache directory.')
   parser.add_argument('--force', action='store_true',
                       help='Always re-install git.')
   parser.add_argument('--verbose', action='store_true')
   args = parser.parse_args(argv)
 
   if os.environ.get('WIN_TOOLS_FORCE') == '1':
     args.force = True
 
   logging.basicConfig(level=logging.INFO if args.verbose else logging.WARN)
 
   git_version = get_target_git_version()
-  git_directory = os.path.join(ROOT_DIR, 'git-%s-64_bin' % git_version)
+  git_directory = os.path.join(
+      ROOT_DIR, 'git-%s-%s_bin' % (git_version, args.bits))
 
   clean_up_old_git_installations(git_directory)
 
   if need_to_install_git(args, git_directory):
     install_git(args, git_version, git_directory)
 
   sync_git_help_files(git_directory)
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))