GN: Add environment variables for sysroot, toolchain

tools/gn.py

 #!/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 multiprocessing
 import os
 import subprocess
 import sys
 import time
 import utils
 
 HOST_OS = utils.GuessOS()
 HOST_ARCH = utils.GuessArchitecture()
 SCRIPT_DIR = os.path.dirname(sys.argv[0])
 DART_ROOT = os.path.realpath(os.path.join(SCRIPT_DIR, '..'))
 
+# Environment variables for default settings.
+DART_USE_ASAN = "DART_USE_ASAN"  # Use instead of --asan
+DART_USE_MSAN = "DART_USE_MSAN"  # Use instead of --msan
+DART_USE_TSAN = "DART_USE_TSAN"  # Use instead of --tsan
+DART_USE_WHEEZY = "DART_USE_WHEEZY"  # Use instread of --wheezy
+DART_USE_TOOLCHAIN = "DART_USE_TOOLCHAIN"  # Use instread of --toolchain-prefix
+DART_USE_SYSROOT = "DART_USE_SYSROOT"  # Use instead of --target-sysroot
+
+def use_asan():
+  return DART_USE_ASAN in os.environ
+
+
+def use_msan():
+  return DART_USE_MSAN in os.environ
+
+
+def use_tsan():
+  return DART_USE_TSAN in os.environ
+
+
+def use_wheezy():
+  return DART_USE_WHEEZY in os.environ
+
+
+def toolchain_prefix(args):
+  if args.toolchain_prefix:
+    return args.toolchain_prefix
+  return os.environ.get(DART_USE_TOOLCHAIN)
+
+
+def target_sysroot(args):
+  if args.target_sysroot:
+    return args.target_sysroot
+  return os.environ.get(DART_USE_SYSROOT)
+
 
 def get_out_dir(mode, arch, target_os):
   return utils.GetBuildRoot(HOST_OS, mode, arch, target_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)
@@ skipping 28 matching lines @@
 
 
 def host_os_for_gn(host_os):
   if host_os.startswith('macos'):
     return 'mac'
   if host_os.startswith('win'):
     return 'win'
   return host_os
 
 
+# Where string_map is formatted as X1=Y1,X2=Y2 etc.
+# If key is X1, returns Y1.
+def parse_string_map(key, string_map):
+  for m in string_map.split(','):
+    l = m.split('=')
+    if l[0] == key:
+      return l[1]
+  return None
+
+
 def to_gn_args(args, mode, arch, target_os):
   gn_args = {}
 
   host_os = host_os_for_gn(HOST_OS)
   if target_os == 'host':
     gn_args['target_os'] = host_os
   else:
     gn_args['target_os'] = target_os
 
   gn_args['dart_target_arch'] = arch
@@ skipping 53 matching lines @@
   gn_args['is_clang'] = args.clang and has_clang
 
   gn_args['is_asan'] = args.asan and gn_args['is_clang']
   gn_args['is_msan'] = args.msan and gn_args['is_clang']
   gn_args['is_tsan'] = args.tsan and gn_args['is_clang']
 
   # Setup the user-defined sysroot.
   if gn_args['target_os'] == 'linux' and args.wheezy:
     gn_args['dart_use_wheezy_sysroot'] = True
   else:
-    if args.target_sysroot:
-      gn_args['target_sysroot'] = args.target_sysroot
+    sysroot = target_sysroot(args)
+    if sysroot:
+      gn_args['target_sysroot'] = parse_string_map(arch, sysroot)
 
-    if args.toolchain_prefix:
-      gn_args['toolchain_prefix'] = args.toolchain_prefix
+    toolchain = toolchain_prefix(args)
+    if toolchain:
+      gn_args['toolchain_prefix'] = parse_string_map(arch, toolchain)
 
   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:
@@ skipping 57 matching lines @@
 
 def ide_switch(host_os):
   if host_os.startswith('win'):
     return '--ide=vs'
   elif host_os.startswith('mac'):
     return '--ide=xcode'
   else:
     return '--ide=json'
 
 
-# Environment variables for default settings.
-DART_USE_ASAN = "DART_USE_ASAN"
-DART_USE_MSAN = "DART_USE_MSAN"
-DART_USE_TSAN = "DART_USE_TSAN"
-DART_USE_WHEEZY = "DART_USE_WHEEZY"
-
-def use_asan():
-  return DART_USE_ASAN in os.environ
-
-def use_msan():
-  return DART_USE_MSAN in os.environ
-
-def use_tsan():
-  return DART_USE_TSAN in os.environ
-
-def use_wheezy():
-  return DART_USE_WHEEZY in os.environ
-
-
 def parse_args(args):
   args = args[1:]
   parser = argparse.ArgumentParser(
       description='A script to run `gn gen`.',
       formatter_class=argparse.ArgumentDefaultsHelpFormatter)
   common_group = parser.add_argument_group('Common Arguments')
   other_group = parser.add_argument_group('Other Arguments')
 
   common_group.add_argument('--arch', '-a',
       type=str,
@@ skipping 46 matching lines @@
   other_group.add_argument('--msan',
       help='Build with MSAN',
       default=use_msan(),
       action='store_true')
   other_group.add_argument('--no-msan',
       help='Disable MSAN',
       dest='msan',
       action='store_false')
   other_group.add_argument('--target-sysroot', '-s',
       type=str,
-      help='Path to the toolchain sysroot')
+      help='Comma-separated list of arch=/path/to/sysroot mappings')
   other_group.add_argument('--toolchain-prefix', '-t',
       type=str,
-      help='Path to the toolchain prefix')
+      help='Comma-separated list of arch=/path/to/toolchain-prefix mappings')
   other_group.add_argument('--tsan',
       help='Build with TSAN',
       default=use_tsan(),
       action='store_true')
   other_group.add_argument('--no-tsan',
       help='Disable TSAN',
       dest='tsan',
       action='store_false')
   other_group.add_argument('--wheezy',
       help='Use the Debian wheezy sysroot on Linux',
@@ skipping 67 matching lines @@
       return 1
 
   endtime = time.time()
   if args.verbose:
     print ("GN Time: %.3f seconds" % (endtime - starttime))
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))