build/rmdir_and_stamp.py

   1 #!/usr/bin/env python
   2 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """Wipes out a directory recursively and then touches a stamp file.
   7
   8 This odd pairing of operations is used to support build scripts which
   9 slurp up entire directories (e.g. build/android/javac.py when handling
  10 generated sources) as inputs.
  11
  12 The general pattern of use is:
  13
  14   - Add a target which generates |gen_sources| into |out_path| from |inputs|.
  15   - Include |stamp_file| as an input for that target or any of its rules which
  16     generate files in |out_path|.
  17   - Add an action which depends on |inputs| and which outputs |stamp_file|;
  18     the action should run this script and pass |out_path| and |stamp_file| as
  19     its arguments.
  20
  21 The net result is that you will force |out_path| to be wiped and all
  22 |gen_sources| to be regenerated any time any file in |inputs| changes.
  23
  24 See //third_party/mojo/mojom_bindings_generator.gypi for an example use case.
  25
  26 """
  27
  28 import errno
  29 import os
  30 import shutil
  31 import sys
  32
  33
  34 def Main(dst_dir, stamp_file):
  35   try:
  36     shutil.rmtree(os.path.normpath(dst_dir))
  37   except OSError as e:
  38     # Ignore only "not found" errors.
  39     if e.errno != errno.ENOENT:
  40       raise e
  41   with open(stamp_file, 'a'):
  42     os.utime(stamp_file, None)
  43
  44 if __name__ == '__main__':
  45   sys.exit(Main(sys.argv[1], sys.argv[2]))