GN: make relocation packing work

build/android/gyp/pack_arm_relocations.py

 #!/usr/bin/env python
 #
 # Copyright 2014 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.
 
 """Pack ARM relative relocations in a library (or copy unchanged).
 
 If --enable-packing and --configuration-name=='Release', invoke the
 relocation_packer tool to pack the .rel.dyn or .rela.dyn section in the given
@@ skipping 17 matching lines @@
 import sys
 import tempfile
 
 from util import build_utils
 
 def PackArmLibraryRelocations(android_pack_relocations,
                               android_objcopy,
                               has_relocations_with_addends,
                               library_path,
                               output_path):
-  if not build_utils.IsTimeStale(output_path, [library_path]):
-    return
-
   # Select an appropriate name for the section we add.
   if has_relocations_with_addends:
     new_section = '.android.rela.dyn'
   else:
     new_section = '.android.rel.dyn'
 
   # Copy and add a 'NULL' packed relocations section for the packing tool.
   with tempfile.NamedTemporaryFile() as stream:
     stream.write('NULL')
     stream.flush()
     objcopy_command = [android_objcopy,
                        '--add-section', '%s=%s' % (new_section, stream.name),
                        library_path, output_path]
     build_utils.CheckOutput(objcopy_command)
 
   # Pack R_ARM_RELATIVE relocations.
   pack_command = [android_pack_relocations, output_path]
   build_utils.CheckOutput(pack_command)
 
 
 def CopyArmLibraryUnchanged(library_path, output_path):
-  if not build_utils.IsTimeStale(output_path, [library_path]):
-    return
-
   shutil.copy(library_path, output_path)
 
 
 def main(args):
   args = build_utils.ExpandFileArgs(args)
   parser = optparse.OptionParser()
+  build_utils.AddDepfileOption(parser)
+  parser.add_option('--clear-dir', action='store_true',
+                    help='If set, the destination directory will be deleted '
+                    'before copying files to it. This is highly recommended to '
+                    'ensure that no stale files are left in the directory.')
 
   parser.add_option('--configuration-name',
       default='Release',
       help='Gyp configuration name (i.e. Debug, Release)')
   parser.add_option('--enable-packing',
       choices=['0', '1'],
       help=('Pack relocations if 1 and configuration name is \'Release\','
             ' otherwise plain file copy'))
   parser.add_option('--has-relocations-with-addends',
       choices=['0', '1'],
@@ skipping 14 matching lines @@
   parser.add_option('--stamp', help='Path to touch on success')
 
   options, _ = parser.parse_args(args)
   enable_packing = (options.enable_packing == '1' and
                     options.configuration_name == 'Release')
   has_relocations_with_addends = (options.has_relocations_with_addends == '1')
   exclude_packing_set = set(shlex.split(options.exclude_packing_list))
 
   libraries = build_utils.ParseGypList(options.libraries)
 
+  if options.clear_dir:
+    build_utils.DeleteDirectory(options.packed_libraries_dir)
+
   build_utils.MakeDirectory(options.packed_libraries_dir)
 
   for library in libraries:
     library_path = os.path.join(options.stripped_libraries_dir, library)
-    output_path = os.path.join(options.packed_libraries_dir, library)
+    output_path = os.path.join(
+        options.packed_libraries_dir, os.path.basename(library))
 
     if enable_packing and library not in exclude_packing_set:
       PackArmLibraryRelocations(options.android_pack_relocations,
                                 options.android_objcopy,
                                 has_relocations_with_addends,
                                 library_path,
                                 output_path)
     else:
       CopyArmLibraryUnchanged(library_path, output_path)
 
+  if options.depfile:
+    build_utils.WriteDepfile(
+        options.depfile,
+        libraries + build_utils.GetPythonDependencies())
+
   if options.stamp:
     build_utils.Touch(options.stamp)
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))