Add iOS support to mac_toolchain download script.

build/mac_toolchain.py

 #!/usr/bin/env python
 # Copyright 2016 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.
 
 """
 If should_use_hermetic_xcode.py emits "1", and the current toolchain is out of
 date:
   * Downloads the hermetic mac toolchain
     * Requires gsutil to be configured.
   * Accepts the license.
     * If xcode-select and xcodebuild are not passwordless in sudoers, requires
       user interaction.
 """
 
 import os
 import plistlib
 import shutil
 import subprocess
 import sys
 import tarfile
 import time
 import tempfile
 import urllib2
 
 # This can be changed after running /build/package_mac_toolchain.py.
-TOOLCHAIN_REVISION = '5B1008'
-TOOLCHAIN_SUB_REVISION = 3
-TOOLCHAIN_VERSION = '%s-%s' % (TOOLCHAIN_REVISION, TOOLCHAIN_SUB_REVISION)
+MAC_TOOLCHAIN_VERSION = '5B1008'
+MAC_TOOLCHAIN_SUB_REVISION = 3
+MAC_TOOLCHAIN_VERSION = '%s-%s' % (MAC_TOOLCHAIN_VERSION,
+                                   MAC_TOOLCHAIN_SUB_REVISION)
+IOS_TOOLCHAIN_VERSION = '8B62'
+IOS_TOOLCHAIN_SUB_REVISION = 1
+IOS_TOOLCHAIN_VERSION = '%s-%s' % (IOS_TOOLCHAIN_VERSION,
+                                   IOS_TOOLCHAIN_SUB_REVISION)
+
+# Absolute path to src/ directory.
+REPO_ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+# Absolute path to a file with gclient solutions.
+GCLIENT_CONFIG = os.path.join(os.path.dirname(REPO_ROOT), '.gclient')
 
 BASE_DIR = os.path.abspath(os.path.dirname(__file__))
 TOOLCHAIN_BUILD_DIR = os.path.join(BASE_DIR, 'mac_files', 'Xcode.app')
 STAMP_FILE = os.path.join(BASE_DIR, 'mac_files', 'toolchain_build_revision')
 TOOLCHAIN_URL = 'gs://chrome-mac-sdk/'
 
+def IsIOSPlatform():
+  try:
+    env = {}
+    execfile(GCLIENT_CONFIG, env, env)
+    if 'ios' in env.get('target_os', []):
+      return True
+  except:
+    pass
+  return False
+
 
 def ReadStampFile():
   """Return the contents of the stamp file, or '' if it doesn't exist."""
   try:
     with open(STAMP_FILE, 'r') as f:
       return f.read().rstrip()
   except IOError:
     return ''
 
 
@@ skipping 119 matching lines @@
 
 
 def main():
   if sys.platform != 'darwin':
     return 0
 
   if not _UseHermeticToolchain():
     print 'Using local toolchain.'
     return 0
 
-  toolchain_revision = os.environ.get('MAC_TOOLCHAIN_REVISION',
-                                      TOOLCHAIN_VERSION)
-  if ReadStampFile() == toolchain_revision:
-    print 'Toolchain (%s) is already up to date.' % toolchain_revision
+  if IsIOSPlatform():
+    default_version = IOS_TOOLCHAIN_VERSION
+    toolchain_filename = 'ios-toolchain-%s.tgz'
+  else:
+    default_version = MAC_TOOLCHAIN_VERSION
+    toolchain_filename = 'toolchain-%s.tgz'
+
+  toolchain_version = os.environ.get('MAC_TOOLCHAIN_REVISION',
+                                      default_version)
+
+  if ReadStampFile() == toolchain_version:
+    print 'Toolchain (%s) is already up to date.' % toolchain_version
     AcceptLicense()
     return 0
 
   if not CanAccessToolchainBucket():
     RequestGsAuthentication()
     return 1
 
   # Reset the stamp file in case the build is unsuccessful.
   WriteStampFile('')
 
-  toolchain_file = '%s.tgz' % toolchain_revision
+  toolchain_file = '%s.tgz' % toolchain_version
   toolchain_full_url = TOOLCHAIN_URL + toolchain_file
 
-  print 'Updating toolchain to %s...' % toolchain_revision
+  print 'Updating toolchain to %s...' % toolchain_version
   try:
-    toolchain_file = 'toolchain-%s.tgz' % toolchain_revision
+    toolchain_file = toolchain_filename % toolchain_version
     toolchain_full_url = TOOLCHAIN_URL + toolchain_file
     DownloadAndUnpack(toolchain_full_url, TOOLCHAIN_BUILD_DIR)
     AcceptLicense()
 
-    print 'Toolchain %s unpacked.' % toolchain_revision
-    WriteStampFile(toolchain_revision)
+    print 'Toolchain %s unpacked.' % toolchain_version
+    WriteStampFile(toolchain_version)
     return 0
   except Exception as e:
     print 'Failed to download toolchain %s.' % toolchain_file
     print 'Exception %s' % e
     print 'Exiting.'
     return 1
 
 if __name__ == '__main__':
   sys.exit(main())