Starting work on full GN build

tools/gn.py

Index: tools/gn.py
diff --git a/tools/gn.py b/tools/gn.py
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+++ b/tools/gn.py
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+#!/usr/bin/env python
+# Copyright 2016 The Dart 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.
+
+import argparse
+import subprocess
+import sys
+import os
+import utils
+
+HOST_OS = utils.GuessOS()
+HOST_ARCH = utils.GuessArchitecture()
+HOST_CPUS = utils.GuessCpus()
+SCRIPT_DIR = os.path.dirname(sys.argv[0])
+DART_ROOT = os.path.realpath(os.path.join(SCRIPT_DIR, '..'))
+
+def get_out_dir(args):
+  return utils.GetBuildRoot(HOST_OS, args.mode, args.arch, args.os)
+
+def to_command_line(gn_args):
+  def merge(key, value):
+    if type(value) is bool:
+      return '%s=%s' % (key, 'true' if value else 'false')
+    return '%s="%s"' % (key, value)
+  return [merge(x, y) for x, y in gn_args.iteritems()]
+
+def host_cpu_for_arch(arch):
+  if arch in ['ia32', 'arm', 'armv6', 'armv5te', 'mips',
+              'simarm', 'simarmv6', 'simarmv5te', 'simmips', 'simdbc']:
+    return 'x86'
+  if arch in ['x64', 'arm64', 'simarm64', 'simdbc64']:
+    return 'x64'
+
+def target_cpu_for_arch(arch, os):
+  if arch in ['ia32', 'simarm', 'simarmv6', 'simarmv5te', 'simmips']:
+    return 'x86'
+  if arch in ['simarm64']:
+    return 'x64'
+  if arch == 'mips':
+    return 'mipsel'
+  if arch == 'simdbc':
+    return 'arm' if os == 'android' else 'x86'
+  if arch == 'simdbc64':
+    return 'arm64' if os == 'android' else 'x64'
+  return arch
+
+def to_gn_args(args):
+  gn_args = {}
+
+  if args.os == 'host':
+    gn_args['target_os'] = HOST_OS
+  else:
+    gn_args['target_os'] = args.os
+
+  gn_args['dart_target_arch'] = args.arch
+  gn_args['target_cpu'] = target_cpu_for_arch(args.arch, args.os)
+  gn_args['host_cpu'] = host_cpu_for_arch(args.arch)
+
+  # TODO(zra): This is for the observatory, which currently builds using the
+  # checked-in sdk. If/when the observatory no longer builds with the
+  # checked-in sdk, this can be removed.
+  gn_args['dart_host_pub_exe'] = os.path.join(
+      DART_ROOT, 'tools', 'sdks', HOST_OS, 'dart-sdk', 'bin', 'pub')
+
+  # For Fuchsia support, the default is to not compile in the root
+  # certificates.
+  gn_args['dart_use_fallback_root_certificates'] = True
+
+  gn_args['dart_zlib_path'] = "//runtime/bin/zlib"
+
+  gn_args['is_debug'] = args.mode == 'debug'
+  gn_args['is_release'] = args.mode == 'release'
+  gn_args['is_product'] = args.mode == 'product'
+  gn_args['dart_debug'] = args.mode == 'debug'
+
+  # This setting is only meaningful for Flutter. Standalone builds of the VM
+  # should leave this set to 'develop', which causes the build to defer to
+  # 'is_debug', 'is_release' and 'is_product'.
+  gn_args['dart_runtime_mode'] = 'develop'
+
+  gn_args['is_clang'] = args.clang and args.os not in ['android']
+
+  if args.target_sysroot:
+    gn_args['target_sysroot'] = args.target_sysroot
+
+  if args.toolchain_prefix:
+    gn_args['toolchain_prefix'] = args.toolchain_prefix
+
+  goma_dir = os.environ.get('GOMA_DIR')
+  goma_home_dir = os.path.join(os.getenv('HOME', ''), 'goma')
+  if args.goma and goma_dir:
+    gn_args['use_goma'] = True
+    gn_args['goma_dir'] = goma_dir
+  elif args.goma and os.path.exists(goma_home_dir):
+    gn_args['use_goma'] = True
+    gn_args['goma_dir'] = goma_home_dir
+  else:
+    gn_args['use_goma'] = False
+    gn_args['goma_dir'] = None
+
+  return gn_args
+
+def parse_args(args):
+  args = args[1:]
+  parser = argparse.ArgumentParser(description='A script run` gn gen`.')
+
+  parser.add_argument('--mode', '-m',
+      type=str,
+      choices=['debug', 'release', 'product'],
+      default='debug')
+  parser.add_argument('--os',
+      type=str,
+      choices=['host', 'android'],
+      default='host')
+  parser.add_argument('--arch', '-a',
+      type=str,
+      choices=['ia32', 'x64', 'simarm', 'arm', 'simarmv6', 'armv6',
+               'simarmv5te', 'armv5te', 'simmips', 'mips', 'simarm64', 'arm64',
+               'simdbc', 'simdbc64'],
+      default='x64')
+
+  parser.add_argument('--goma', default=True, action='store_true')
+  parser.add_argument('--no-goma', dest='goma', action='store_false')
+
+  parser.add_argument('--clang', default=True, action='store_true')
+  parser.add_argument('--no-clang', dest='clang', action='store_false')
+
+  parser.add_argument('--target-sysroot', '-s', type=str)
+  parser.add_argument('--toolchain-prefix', '-t', type=str)
+
+  return parser.parse_args(args)
+
+def main(argv):
+  args = parse_args(argv)
+
+  if sys.platform.startswith(('cygwin', 'win')):
+    subdir = 'win'
+  elif sys.platform == 'darwin':
+    subdir = 'mac'
+  elif sys.platform.startswith('linux'):
+     subdir = 'linux64'
+  else:
+    raise Error('Unknown platform: ' + sys.platform)
+
+  command = [
+    '%s/buildtools/%s/gn' % (DART_ROOT, subdir),
+    'gen',
+    '--check'
+  ]
+  gn_args = to_command_line(to_gn_args(args))
+  out_dir = get_out_dir(args)
+  print "gn gen --check in %s" % out_dir
+  command.append(out_dir)
+  command.append('--args=%s' % ' '.join(gn_args))
+  return subprocess.call(command, cwd=DART_ROOT)
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv))