Rewrite iOS FAT libraries build script in Python

tools-webrtc/ios/build_ios_libs.py

Index: tools-webrtc/ios/build_ios_libs.py
diff --git a/tools-webrtc/ios/build_ios_libs.py b/tools-webrtc/ios/build_ios_libs.py
new file mode 100755
index 0000000000000000000000000000000000000000..550c7a1b70bcda95f7329d8319a3d7758be2c83c
--- /dev/null
+++ b/tools-webrtc/ios/build_ios_libs.py
@@ -0,0 +1,221 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+#
+# Use of this source code is governed by a BSD-style license
+# that can be found in the LICENSE file in the root of the source
+# tree. An additional intellectual property rights grant can be found
+# in the file PATENTS.  All contributing project authors may
+# be found in the AUTHORS file in the root of the source tree.
+
+"""WebRTC iOS FAT libraries build script.
+Each architecture is compiled separately before being merged together.
+By default, the library is created in out_ios_libs/. (Change with -o.)
+The headers will be copied to out_ios_libs/include.
+"""
+
+import argparse
+import distutils.dir_util
+import logging
+import os
+import shutil
+import subprocess
+import sys
+
+
+os.environ['PATH'] = '/usr/libexec' + os.pathsep + os.environ['PATH']
+
+SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+WEBRTC_BASE_DIR = os.path.abspath(os.path.join(SCRIPT_DIR, '..', '..'))
+SDK_OUTPUT_DIR = os.path.join(WEBRTC_BASE_DIR, 'out_ios_libs')
+SDK_LIB_NAME = 'librtc_sdk_objc.a'
+SDK_FRAMEWORK_NAME = 'WebRTC.framework'
+
+ENABLED_ARCHITECTURES = ['arm', 'arm64', 'x64']
+IOS_DEPLOYMENT_TARGET = '8.0'
+LIBVPX_BUILD_VP9 = False
+CUSTOM_GN_OPTS = [] # example: ['some_option=foo bar', 'other_option=true']
+
+
+def _ParseArgs():
+  parser = argparse.ArgumentParser(description=__doc__)
+  parser.add_argument('-b', '--build_type', default='framework',
+      choices=['framework', 'static_only'],
+      help='The build type. Can be "framework" or "static_only". '
+           'Defaults to "framework".')
+  parser.add_argument('--build_config', default='release',
+      choices=['debug', 'release'],
+      help='The build config. Can be "debug" or "release". '
+           'Defaults to "release".')
+  parser.add_argument('-c', '--clean', action='store_true', default=False,
+      help='Removes the previously generated build output, if any.')
+  parser.add_argument('-o', '--output-dir', default=SDK_OUTPUT_DIR,
+      help='Specifies a directory to output the build artifacts to. '
+           'If specified together with -c, deletes the dir.')
+  parser.add_argument('-r', '--revision', type=int, default=0,
+      help='Specifies a revision number to embed if building the framework.')
+  parser.add_argument('-e', '--bitcode', action='store_true', default=False,
+      help='Compile with bitcode.')
+  parser.add_argument('--verbose', action='store_true', default=False,
+      help='Debug logging.')
+  return parser.parse_args()
+
+
+def _RunCommand(cmd):
+  logging.debug('Running: %r', cmd)
+  subprocess.check_call(cmd)
+
+
+def _CleanArtifacts(output_dir):
+  if os.path.isdir(output_dir):
+    logging.info('Deleting %s', output_dir)
+    shutil.rmtree(output_dir)
+
+
+def BuildWebRTC(output_dir, target_arch, flavor, build_type,
+                ios_deployment_target, libvpx_build_vp9, use_bitcode,
+                custom_gn_options=()):
+  output_dir = os.path.join(output_dir, target_arch + '_libs')
+  gn_args = ['target_os="ios"', 'ios_enable_code_signing=false',
+             'use_xcode_clang=true', 'is_component_build=false']
+
+  # Add flavor option.
+  if flavor == 'debug':
+    gn_args.append('is_debug=true')
+  elif flavor == 'release':
+    gn_args.append('is_debug=false')
+  else:
+    raise ValueError('Unexpected flavor type: %s' % flavor)
+
+  gn_args.append('target_cpu="%s"' % target_arch)
+
+  gn_args.append('ios_deployment_target="%s"' % ios_deployment_target)
+
+  gn_args.append('rtc_libvpx_build_vp9=' +
+                 ('true' if libvpx_build_vp9 else 'false'))
+
+  gn_args.append('enable_ios_bitcode=' +
+                 ('true' if use_bitcode else 'false'))
+
+  gn_args.extend(custom_gn_options)
+
+  # Generate static or dynamic.
+  if build_type == 'static_only':
+    gn_target_name = 'rtc_sdk_objc'
+  elif build_type == 'framework':
+    gn_target_name = 'rtc_sdk_framework_objc'
+    gn_args.append('enable_dsyms=true')
+    gn_args.append('enable_stripping=true')
+  else:
+    raise ValueError('Build type "%s" is not supported.' % build_type)
+
+  logging.info('Building WebRTC with args: %s', ' '.join(gn_args))
+  cmd = ['gn', 'gen', output_dir,
+         '--args=' + ' '.join(gn_args)]
+  _RunCommand(cmd)
+  logging.info('Building target: %s', gn_target_name)
+  cmd = ['ninja', '-C', output_dir, gn_target_name]
+  _RunCommand(cmd)
+
+  # Strip debug symbols to reduce size.
+  if build_type == 'static_only':
+    gn_target_path = os.path.join(output_dir, 'obj', 'webrtc', 'sdk',
+                                  'lib%s.a' % gn_target_name)
+    cmd = ['strip', '-S', gn_target_path, '-o',
+           os.path.join(output_dir, 'lib%s.a' % gn_target_name)]
+    _RunCommand(cmd)
+
+
+def main():
+  args = _ParseArgs()
+
+  logging.basicConfig(level=logging.DEBUG if args.verbose else logging.INFO)
+
+  if args.clean:
+    _CleanArtifacts(args.output_dir)
+    return 0
+
+  # Build all architectures.
+  for arch in ENABLED_ARCHITECTURES:
+    BuildWebRTC(args.output_dir, arch, args.build_config, args.build_type,
+                IOS_DEPLOYMENT_TARGET, LIBVPX_BUILD_VP9, args.bitcode,
+                CUSTOM_GN_OPTS)
+
+  # Ignoring x86 except for static libraries for now because of a GN build issue
+  # where the generated dynamic framework has the wrong architectures.
+
+  # Create FAT archive.
+  if args.build_type == 'static_only':
+    BuildWebRTC(args.output_dir, 'x86', args.build_config, args.build_type,
+                IOS_DEPLOYMENT_TARGET, LIBVPX_BUILD_VP9, args.bitcode,
+                CUSTOM_GN_OPTS)
+
+    arm_lib_path = os.path.join(args.output_dir, 'arm_libs', SDK_LIB_NAME)
+    arm64_lib_path = os.path.join(args.output_dir, 'arm64_libs', SDK_LIB_NAME)
+    x64_lib_path = os.path.join(args.output_dir, 'x64_libs', SDK_LIB_NAME)
+    x86_lib_path = os.path.join(args.output_dir, 'x86_libs', SDK_LIB_NAME)
+
+    # Combine the slices.
+    cmd = ['lipo', arm_lib_path, arm64_lib_path, x64_lib_path, x86_lib_path,
+           '-create', '-output', os.path.join(args.output_dir, SDK_LIB_NAME)]
+    _RunCommand(cmd)
+
+  elif args.build_type == 'framework':
+    arm_lib_path = os.path.join(args.output_dir, 'arm_libs')
+    arm64_lib_path = os.path.join(args.output_dir, 'arm64_libs')
+    x64_lib_path = os.path.join(args.output_dir, 'x64_libs')
+
+    # Combine the slices.
+    dylib_path = os.path.join(SDK_FRAMEWORK_NAME, 'WebRTC')
+    # Use distutils instead of shutil to support merging folders.
+    distutils.dir_util.copy_tree(
+        os.path.join(arm64_lib_path, SDK_FRAMEWORK_NAME),
+        os.path.join(args.output_dir, SDK_FRAMEWORK_NAME))
+    try:
+      os.remove(os.path.join(args.output_dir, dylib_path))
+    except OSError:
+      pass
+    logging.info('Merging framework slices.')
+    cmd = ['lipo', os.path.join(arm_lib_path, dylib_path),
+           os.path.join(arm64_lib_path, dylib_path),
+           os.path.join(x64_lib_path, dylib_path),
+           '-create', '-output', os.path.join(args.output_dir, dylib_path)]
+    _RunCommand(cmd)
+
+    # Merge the dSYM slices.
+    dsym_path = os.path.join('WebRTC.dSYM', 'Contents', 'Resources', 'DWARF',
+                             'WebRTC')
+    distutils.dir_util.copy_tree(os.path.join(arm64_lib_path, 'WebRTC.dSYM'),
+                                 os.path.join(args.output_dir, 'WebRTC.dSYM'))
+    try:
+      os.remove(os.path.join(args.output_dir, dsym_path))
+    except OSError:
+      pass
+    logging.info('Merging dSYM slices.')
+    cmd = ['lipo', os.path.join(arm_lib_path, dsym_path),
+           os.path.join(arm64_lib_path, dsym_path),
+           os.path.join(x64_lib_path, dsym_path),
+           '-create', '-output', os.path.join(args.output_dir, dsym_path)]
+    _RunCommand(cmd)
+
+    # Modify the version number.
+    # Format should be <Branch cut MXX>.<Hotfix #>.<Rev #>.
+    # e.g. 55.0.14986 means branch cut 55, no hotfixes, and revision 14986.
+    infoplist_path = os.path.join(args.output_dir, SDK_FRAMEWORK_NAME,
+                                  'Info.plist')
+    cmd = ['PlistBuddy', '-c',
+           'Print :CFBundleShortVersionString', infoplist_path]
+    major_minor = subprocess.check_output(cmd).strip()
+    version_number = '%s.%s' % (major_minor, args.revision)
+    logging.info('Substituting revision number: %s', version_number)
+    cmd = ['PlistBuddy', '-c',
+           'Set :CFBundleVersion ' + version_number, infoplist_path]
+    _RunCommand(cmd)
+    _RunCommand(['plutil', '-convert', 'binary1', infoplist_path])
+
+  logging.info('Done.')
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())