src/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 section in the given library
  11 files.  This step is inserted after the libraries are stripped.  Packing
  12 adds a new .android.rel.dyn section to the file and reduces the size of
  13 .rel.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                               library_path,
  36                               output_path):
  37   if not build_utils.IsTimeStale(output_path, [library_path]):
  38     return
  39
  40   # Copy and add a 'NULL' .android.rel.dyn section for the packing tool.
  41   with tempfile.NamedTemporaryFile() as stream:
  42     stream.write('NULL')
  43     stream.flush()
  44     objcopy_command = [android_objcopy,
  45                        '--add-section', '.android.rel.dyn=%s' % stream.name,
  46                        library_path, output_path]
  47     build_utils.CheckOutput(objcopy_command)
  48
  49   # Pack R_ARM_RELATIVE relocations.
  50   pack_command = [android_pack_relocations, output_path]
  51   build_utils.CheckOutput(pack_command)
  52
  53
  54 def CopyArmLibraryUnchanged(library_path, output_path):
  55   if not build_utils.IsTimeStale(output_path, [library_path]):
  56     return
  57
  58   shutil.copy(library_path, output_path)
  59
  60
  61 def main(args):
  62   args = build_utils.ExpandFileArgs(args)
  63   parser = optparse.OptionParser()
  64
  65   parser.add_option('--configuration-name',
  66       default='Release',
  67       help='Gyp configuration name (i.e. Debug, Release)')
  68   parser.add_option('--enable-packing',
  69       choices=['0', '1'],
  70       help=('Pack relocations if 1 and configuration name is \'Release\','
  71             ' otherwise plain file copy'))
  72   parser.add_option('--exclude-packing-list',
  73       default='',
  74       help='Names of any libraries explicitly not packed')
  75   parser.add_option('--android-pack-relocations',
  76       help='Path to the ARM relocations packer binary')
  77   parser.add_option('--android-objcopy',
  78       help='Path to the toolchain\'s objcopy binary')
  79   parser.add_option('--stripped-libraries-dir',
  80       help='Directory for stripped libraries')
  81   parser.add_option('--packed-libraries-dir',
  82       help='Directory for packed libraries')
  83   parser.add_option('--libraries',
  84       help='List of libraries')
  85   parser.add_option('--stamp', help='Path to touch on success')
  86
  87   options, _ = parser.parse_args(args)
  88   enable_packing = (options.enable_packing == '1' and
  89                     options.configuration_name == 'Release')
  90   exclude_packing_set = set(shlex.split(options.exclude_packing_list))
  91
  92   libraries = build_utils.ParseGypList(options.libraries)
  93
  94   build_utils.MakeDirectory(options.packed_libraries_dir)
  95
  96   for library in libraries:
  97     library_path = os.path.join(options.stripped_libraries_dir, library)
  98     output_path = os.path.join(options.packed_libraries_dir, library)
  99
 100     if enable_packing and library not in exclude_packing_set:
 101       PackArmLibraryRelocations(options.android_pack_relocations,
 102                                 options.android_objcopy,
 103                                 library_path,
 104                                 output_path)
 105     else:
 106       CopyArmLibraryUnchanged(library_path, output_path)
 107
 108   if options.stamp:
 109     build_utils.Touch(options.stamp)
 110
 111   return 0
 112
 113
 114 if __name__ == '__main__':
 115   sys.exit(main(sys.argv[1:]))