build/android/gyp/pack_arm_relocations.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2014 The Chromium Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6
   7 """Pack ARM relative relocations in a library (or copy unchanged).
   8
   9 If --enable-packing and --configuration-name=='Release', invoke the
  10 relocation_packer tool to pack the .rel.dyn or .rela.dyn section in the given
  11 library files.  This step is inserted after the libraries are stripped.
  12 Packing adds a new .android.rel.dyn or .android.rela.dyn section to the file
  13 and reduces the size of .rel.dyn or .rela.dyn accordingly.
  14
  15 Currently packing only understands ARM32 shared libraries.  For all other
  16 architectures --enable-packing should be set to zero.  In this case the
  17 script copies files verbatim, with no attempt to pack relative relocations.
  18
  19 Any library listed in --exclude-packing-list is also copied verbatim,
  20 irrespective of any --enable-packing setting.  Typically this would be
  21 'libchromium_android_linker.so'.
  22 """
  23
  24 import optparse
  25 import os
  26 import shlex
  27 import shutil
  28 import sys
  29 import tempfile
  30
  31 from util import build_utils
  32
  33 def PackArmLibraryRelocations(android_pack_relocations,
  34                               android_objcopy,
  35                               has_relocations_with_addends,
  36                               library_path,
  37                               output_path):
  38   # Select an appropriate name for the section we add.
  39   if has_relocations_with_addends:
  40     new_section = '.android.rela.dyn'
  41   else:
  42     new_section = '.android.rel.dyn'
  43
  44   # Copy and add a 'NULL' packed relocations section for the packing tool.
  45   with tempfile.NamedTemporaryFile() as stream:
  46     stream.write('NULL')
  47     stream.flush()
  48     objcopy_command = [android_objcopy,
  49                        '--add-section', '%s=%s' % (new_section, stream.name),
  50                        library_path, output_path]
  51     build_utils.CheckOutput(objcopy_command)
  52
  53   # Pack R_ARM_RELATIVE relocations.
  54   pack_command = [android_pack_relocations, output_path]
  55   build_utils.CheckOutput(pack_command)
  56
  57
  58 def CopyArmLibraryUnchanged(library_path, output_path):
  59   shutil.copy(library_path, output_path)
  60
  61
  62 def main(args):
  63   args = build_utils.ExpandFileArgs(args)
  64   parser = optparse.OptionParser()
  65   build_utils.AddDepfileOption(parser)
  66   parser.add_option('--clear-dir', action='store_true',
  67                     help='If set, the destination directory will be deleted '
  68                     'before copying files to it. This is highly recommended to '
  69                     'ensure that no stale files are left in the directory.')
  70
  71   parser.add_option('--configuration-name',
  72       default='Release',
  73       help='Gyp configuration name (i.e. Debug, Release)')
  74   parser.add_option('--enable-packing',
  75       choices=['0', '1'],
  76       help=('Pack relocations if 1 and configuration name is \'Release\','
  77             ' otherwise plain file copy'))
  78   parser.add_option('--has-relocations-with-addends',
  79       choices=['0', '1'],
  80       help=('Pack into \'.android.rela.dyn\' if 1, else \'.android.rel.dyn\''))
  81   parser.add_option('--exclude-packing-list',
  82       default='',
  83       help='Names of any libraries explicitly not packed')
  84   parser.add_option('--android-pack-relocations',
  85       help='Path to the ARM relocations packer binary')
  86   parser.add_option('--android-objcopy',
  87       help='Path to the toolchain\'s objcopy binary')
  88   parser.add_option('--stripped-libraries-dir',
  89       help='Directory for stripped libraries')
  90   parser.add_option('--packed-libraries-dir',
  91       help='Directory for packed libraries')
  92   parser.add_option('--libraries', action='append',
  93       help='List of libraries')
  94   parser.add_option('--stamp', help='Path to touch on success')
  95
  96   options, _ = parser.parse_args(args)
  97   enable_packing = (options.enable_packing == '1' and
  98                     options.configuration_name == 'Release')
  99   has_relocations_with_addends = (options.has_relocations_with_addends == '1')
 100   exclude_packing_set = set(shlex.split(options.exclude_packing_list))
 101
 102   libraries = []
 103   for libs_arg in options.libraries:
 104     libraries += build_utils.ParseGypList(libs_arg)
 105
 106   if options.clear_dir:
 107     build_utils.DeleteDirectory(options.packed_libraries_dir)
 108
 109   build_utils.MakeDirectory(options.packed_libraries_dir)
 110
 111   for library in libraries:
 112     library_path = os.path.join(options.stripped_libraries_dir, library)
 113     output_path = os.path.join(
 114         options.packed_libraries_dir, os.path.basename(library))
 115
 116     if enable_packing and library not in exclude_packing_set:
 117       PackArmLibraryRelocations(options.android_pack_relocations,
 118                                 options.android_objcopy,
 119                                 has_relocations_with_addends,
 120                                 library_path,
 121                                 output_path)
 122     else:
 123       CopyArmLibraryUnchanged(library_path, output_path)
 124
 125   if options.depfile:
 126     build_utils.WriteDepfile(
 127         options.depfile,
 128         libraries + build_utils.GetPythonDependencies())
 129
 130   if options.stamp:
 131     build_utils.Touch(options.stamp)
 132
 133   return 0
 134
 135
 136 if __name__ == '__main__':
 137   sys.exit(main(sys.argv[1:]))