webrtc ios client 原始碼拉取和編譯

環境

• Mac 10.13.1
• Xcode 9.1
• 翻牆代理：Lantern 4.4.1 (20171120.170626)
• Python 2.7.10

設定 git 代理

#設定git代理
$ git config --global http.proxy http://127.0.0.1:xxxx
$ git config --global https.proxy https://127.0.0.1:xxxx
#清空git代理
$ git config --global --unset http.proxy
$ git config --global
 
 --unset https.proxy

• 注意：代理地址的埠要用Lantern代理監聽的埠地址

安裝 Depot_tools

• git 命令獲取 depot_tools：

$ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git

• 配置壞境變數

$ echo -e "\nexport PATH=$PWD/depot_tools:$PATH" >> $HOME/.bash_profile
$ echo -e "\nexport DEPOT_TOOLS_UPDATE=0"
 
 >> $HOME/.bash_profile
$ source $HOME/.bash_profile

• 檢測配置是否成功

$ echo $PATH

安裝 ninja

• ninja 是 WebRTC 的編譯工具，我們需要對其進行編譯，步驟如下：

$ git clone git://github.com/martine/ninja.git
$ cd ninja/
$ ./bootstrap.py

• 複製到系統目錄（也可配置壞境變數）

$ sudo cp ninja /usr/local/bin/
$ sudo chmod a+rx /usr/local
 
/bin/ninja

設定 boto 代理

• 建立http_proxy.boto檔案，在裡面輸入如下內容：

[Boto] 
proxy=127.0.0.1
proxy_port=xxxx #此埠號為Lantern的監聽的埠號

• 配置壞境變數

$ echo -e "\nexport NO_AUTH_BOTO_CONFIG=$PWD/http_proxy.boto" >> $HOME/.bash_profile
$ source $HOME/.bash_profile

• 檢測配置是否成功

$ echo $NO_AUTH_BOTO_CONFIG

下載原始碼

$ export GYP_DEFINES="OS=ios"
$ fetch --nohooks webrtc_ios
$ gclient sync -r 6f21dc245689c29730002da09534a8d275e6aa92 --force
$ gclient runhooks

上面的 commit id 是 M62 版本最後一次 commit id，可以從 Release Notes 中找到，可替換成自己所需的版本的 commit id 或者直接使用最新的 commit id，如果gclient sync失敗，請再次gclient sync

程式碼編譯

$ gn gen out/ios --args='target_os="ios" additional_target_cpus=["arm"] target_cpu="arm64"' --ide=xcode
# gn gen out/Default --args="target_os=\"win\" target_cpu=\"x86\" is_debug=false" –ide=vs2017 
# windows版本
$ open -a Xcode.app out/ios/all.xcworkspace

編譯Webrtc.framework動態庫

$ ./tools_webrtc/ios/build_ios_libs.sh #編譯完成後會在src資料夾下生成一個out_ios_libs的資料夾，編譯好的動態庫就在裡面

看一下編譯指令碼build_ios_libs.py 如下：

#!/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.)
"""

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__))
SRC_DIR = os.path.abspath(os.path.join(SCRIPT_DIR, '..', '..'))
sys.path.append(os.path.join(SRC_DIR, 'build'))
import find_depot_tools

SDK_OUTPUT_DIR = os.path.join(SRC_DIR, 'out_ios_libs') #編譯動態庫的輸出路徑，可以自己修改
SDK_LIB_NAME = 'librtc_sdk_objc.a'
SDK_FRAMEWORK_NAME = 'WebRTC.framework' #動態庫的名稱，可自己修改

DEFAULT_ARCHS = ENABLED_ARCHS = ['arm64', 'arm', 'x64', 'x86'] #支援的指令集
IOS_DEPLOYMENT_TARGET = '9.0' #支援的iOS系統版本
LIBVPX_BUILD_VP9 = False #是否編譯VP9

sys.path.append(os.path.join(SCRIPT_DIR, '..', 'libs'))
from generate_licenses import LicenseBuilder


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('--arch', nargs='+', default=DEFAULT_ARCHS,
      choices=ENABLED_ARCHS,
      help='Architectures to build. Defaults to %(default)s.')
  parser.add_argument('-c', '--clean', action='store_true', default=False,
      help='Removes the previously generated build output, if any.')
  parser.add_argument('-p', '--purify', action='store_true', default=False,
      help='Purifies the previously generated build output by '
           'removing the temporary results used when (re)building.')
  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.')
  parser.add_argument('--use-goma', action='store_true', default=False,
      help='Use goma to build.')
  parser.add_argument('--extra-gn-args', default=[], nargs='*',
      help='Additional GN args to be used during Ninja generation.')

  return parser.parse_args()


def _RunCommand(cmd):
  logging.debug('Running: %r', cmd)
  subprocess.check_call(cmd, cwd=SRC_DIR)


def _CleanArtifacts(output_dir):
  if os.path.isdir(output_dir):
    logging.info('Deleting %s', output_dir)
    shutil.rmtree(output_dir)


def _CleanTemporary(output_dir, architectures):
  if os.path.isdir(output_dir):
    logging.info('Removing temporary build files.')
    for arch in architectures:
      arch_lib_path = os.path.join(output_dir, arch + '_libs')
      if os.path.isdir(arch_lib_path):
        shutil.rmtree(arch_lib_path)


def BuildWebRTC(output_dir, target_arch, flavor, gn_target_name,
                ios_deployment_target, libvpx_build_vp9, use_bitcode,
                use_goma, extra_gn_args, static_only):
  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.append('use_goma=' + ('true' if use_goma else 'false'))

  args_string = ' '.join(gn_args + extra_gn_args)
  logging.info('Building WebRTC with args: %s', args_string)

  cmd = [
    sys.executable,
    os.path.join(find_depot_tools.DEPOT_TOOLS_PATH, 'gn.py'),
    'gen',
    output_dir,
    '--args=' + args_string,
  ]
  _RunCommand(cmd)
  logging.info('Building target: %s', gn_target_name)

  cmd = [
    os.path.join(find_depot_tools.DEPOT_TOOLS_PATH, 'ninja'),
    '-C',
    output_dir,
    gn_target_name,
  ]
  if use_goma:
    cmd.extend(['-j', '200'])
  _RunCommand(cmd)

  # Strip debug symbols to reduce size.
  if static_only:
    gn_target_path = os.path.join(output_dir, 'obj', '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

  architectures = list(args.arch)
  gn_args = args.extra_gn_args

  if args.purify:
    _CleanTemporary(args.output_dir, architectures)
    return 0

  # Ignoring x86 except for static libraries for now because of a GN build issue
  # where the generated dynamic framework has the wrong architectures.
  if 'x86' in architectures and args.build_type != 'static_only':
    architectures.remove('x86')

  # Generate static or dynamic.
  if args.build_type == 'static_only':
    gn_target_name = 'rtc_sdk_objc'
  elif args.build_type == 'framework':
    gn_target_name = 'framework_objc'
    if not args.bitcode:
      gn_args.append('enable_dsyms=true')
    gn_args.append('enable_stripping=true')
  else:
    raise ValueError('Build type "%s" is not supported.' % args.build_type)


  # Build all architectures.
  for arch in architectures:
    BuildWebRTC(args.output_dir, arch, args.build_config, gn_target_name,
                IOS_DEPLOYMENT_TARGET, LIBVPX_BUILD_VP9, args.bitcode,
                args.use_goma, gn_args, args.build_type == 'static_only')

  # Create FAT archive.
  if args.build_type == 'static_only':
    lib_paths = [os.path.join(args.output_dir, arch + '_libs', SDK_LIB_NAME)
                 for arch in architectures]
    out_lib_path = os.path.join(args.output_dir, SDK_LIB_NAME)
    # Combine the slices.
    cmd = ['lipo'] + lib_paths + ['-create', '-output', out_lib_path]
    _RunCommand(cmd)

  elif args.build_type == 'framework':
    lib_paths = [os.path.join(args.output_dir, arch + '_libs')
                 for arch in architectures]

    # Combine the slices.
    dylib_path = os.path.join(SDK_FRAMEWORK_NAME, 'WebRTC')
    # Dylibs will be combined, all other files are the same across archs.
    # Use distutils instead of shutil to support merging folders.
    distutils.dir_util.copy_tree(
        os.path.join(lib_paths[0], SDK_FRAMEWORK_NAME),
        os.path.join(args.output_dir, SDK_FRAMEWORK_NAME))
    logging.info('Merging framework slices.')
    dylib_paths = [os.path.join(path, dylib_path) for path in lib_paths]
    out_dylib_path = os.path.join(args.output_dir, dylib_path)
    try:
      os.remove(out_dylib_path)
    except OSError:
      pass
    cmd = ['lipo'] + dylib_paths + ['-create', '-output', out_dylib_path]
    _RunCommand(cmd)

    # Merge the dSYM slices.
    lib_dsym_dir_path = os.path.join(lib_paths[0], 'WebRTC.dSYM')
    if os.path.isdir(lib_dsym_dir_path):
      distutils.dir_util.copy_tree(lib_dsym_dir_path,
                                   os.path.join(args.output_dir, 'WebRTC.dSYM'))
      logging.info('Merging dSYM slices.')
      dsym_path = os.path.join('WebRTC.dSYM', 'Contents', 'Resources', 'DWARF',
                               'WebRTC')
      lib_dsym_paths = [os.path.join(path, dsym_path) for path in lib_paths]
      out_dsym_path = os.path.join(args.output_dir, dsym_path)
      try:
        os.remove(out_dsym_path)
      except OSError:
        pass
      cmd = ['lipo'] + lib_dsym_paths + ['-create', '-output', out_dsym_path]
      _RunCommand(cmd)

    # Generate the license file.
    ninja_dirs = [os.path.join(args.output_dir, arch + '_libs')
                  for arch in architectures]
    gn_target_full_name = '//sdk:' + gn_target_name
    builder = LicenseBuilder(ninja_dirs, [gn_target_full_name])
    builder.GenerateLicenseText(
        os.path.join(args.output_dir, SDK_FRAMEWORK_NAME))


    # 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())