GN

gn.py

+#!/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 subprocess
+import sys
+
+def quiet(*cmd):
+  cmd = ' '.join(cmd).split()
+  subprocess.check_output(cmd)
+
+def loud(*cmd):
+  cmd = ' '.join(cmd).split()
+  ret = subprocess.call(cmd)
+  if ret != 0:
+    sys.exit(ret)
+
+def gn_path():
+  if 'linux' in sys.platform:
+    return 'buildtools/linux64/gn'
+  if 'darwin' in sys.platform:
+    return 'buildtools/mac/gn'
+  return 'buildtools/win/gn.exe'
+
+# Make sure we've got an up-to-date GN and Clang, and sysroot on Linux.
+quiet('download_from_google_storage',
+     '--no_resume --no_auth --bucket chromium-gn',
+     '-s ', gn_path() + '.sha1')
+quiet('python tools/clang/scripts/update.py --if-needed')
+if 'linux' in sys.platform:
+  quiet('python build/linux/sysroot_scripts/install-sysroot.py --arch=amd64')
+
+# Pass all our arguments over to the real GN binary.
+loud(gn_path(), *sys.argv[1:])