Add a wrapper script which modifies the .isolate on the fly.

tools/isolate_driver.py

Index: tools/isolate_driver.py
diff --git a/tools/isolate_driver.py b/tools/isolate_driver.py
new file mode 100755
index 0000000000000000000000000000000000000000..4a20f22a4688b86e5310bc217c78fbbf8cc6a414
--- /dev/null
+++ b/tools/isolate_driver.py
@@ -0,0 +1,132 @@
+#!/usr/bin/env python
+# Copyright 2014 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.
+
+"""Adaptor script called through build/isolate.gypi.
+
+Creates a wrapping .isolate which 'includes' the original one, that can be
+consumed by tools/swarming_client/isolate.py. Path variables are determined
+based on the current working directory. The relative_cwd in the .isolated file
+is determined based on *the .isolate file that declare the 'command' variable to
+be used* so the wrapping .isolate doesn't affect this value.
+
+It packages all the dynamic libraries found in this wrapping .isolate. This is
+inefficient and non-deterministic. In the very near future, it will parse
+build.ninja, find back the root target and find all the dynamic libraries that
+are marked as a dependency to this target.
+"""
+
+import glob
+import os
+import posixpath
+import subprocess
+import sys
+
+TOOLS_DIR = os.path.dirname(os.path.abspath(__file__))
+SWARMING_CLIENT_DIR = os.path.join(TOOLS_DIR, 'swarming_client')
+SRC_DIR = os.path.dirname(TOOLS_DIR)
+
+sys.path.insert(0, SWARMING_CLIENT_DIR)
+
+import isolate_format
+
+
+
+# Location to grab binaries based on the OS.
+DYNAMIC_LIBRARIES = {
+  'darwin': '*.dylib',
+  'linux2': 'lib/*.so',
+  'win32': '*.dll',
+}
+
+
+def create_wrapper(args, isolate_index, isolated_index):
+  """Creates a wrapper .isolate that add dynamic libs.
+
+  The original .isolate is not modified.
+  """
+  cwd = os.getcwd()
+  isolate = args[isolate_index]
+  # The code assumes the .isolate file is always specified path-less in cwd. Fix
+  # if this assumption doesn't hold true.
+  assert os.path.basename(isolate) == isolate, isolate
+
+  # This will look like ../out/Debug. This is based against cwd. Note that this
+  # must equal the value provided as PRODUCT_DIR.
+  build_dir = os.path.dirname(args[isolated_index])
+
+  # This will look like chrome/unit_tests.isolate. It is based against SRC_DIR.
+  # It's used to calculate temp_isolate.
+  src_isolate = os.path.relpath(os.path.join(cwd, isolate), SRC_DIR)
+
+  # The wrapping .isolate. This will look like
+  # ../out/Debug/gen/chrome/unit_tests.isolate.
+  temp_isolate = os.path.join(build_dir, 'gen', src_isolate)
+  temp_isolate_dir = os.path.dirname(temp_isolate)
+
+  # Relative path between the new and old .isolate file.
+  isolate_relpath = os.path.relpath(
+      '.', temp_isolate_dir).replace(os.path.sep, '/')
+
+  # This will look like [../out/Debug/lib/libuser_prefs.so].
+  dynamic_libs = [
+    i.replace(os.path.sep, '/')
+    for i in glob.iglob(
+        os.path.join(build_dir, DYNAMIC_LIBRARIES[sys.platform]))
+  ]
+  # And now like ['<(PRODUCT_DIR)/lib/flibuser_prefs.so'].
+  rebased_libs = [
+    '<(PRODUCT_DIR)/%s' % i[len(build_dir)+1:]
+    for i in dynamic_libs
+  ]
+
+  # Now do actual wrapping .isolate.
+  out = {
+    'includes': [
+      posixpath.join(isolate_relpath, isolate),
+    ],
+    'variables': {
+      isolate_format.KEY_TRACKED: rebased_libs,
+    },
+  }
+  if not os.path.isdir(temp_isolate_dir):
+    os.makedirs(temp_isolate_dir)
+  comment = (
+      '# Warning: this file was AUTOGENERATED.\n'
+      '# DO NO EDIT.\n')
+  with open(temp_isolate, 'wb') as f:
+    isolate_format.print_all(comment, out, f)
+  if '--verbose' in args:
+    print('Added %d dynamic libs' % len(dynamic_libs))
+  args[isolate_index] = temp_isolate
+
+
+def main():
+  args = sys.argv[1:]
+  isolate = None
+  isolated = None
+  is_component = False
+  for i, arg in enumerate(args):
+    if arg == '--isolate':
+      isolate = i + 1
+    if arg == '--isolated':
+      isolated = i + 1
+    if arg == 'component=shared_library':
+      is_component = True
+  if isolate is None or isolated is None:
+    print >> sys.stderr, 'Internal failure'
+    return 1
+
+  if is_component:
+    create_wrapper(args, isolate, isolated)
+
+  swarming_client = os.path.join(SRC_DIR, 'tools', 'swarming_client')
+  sys.stdout.flush()
+  result = subprocess.call(
+      [sys.executable, os.path.join(swarming_client, 'isolate.py')] + args)
+  return result
+
+
+if __name__ == '__main__':
+  sys.exit(main())