Link applications with -Wl,-ObjC to keep Objective-C implementations availabl...

build/mac/make_ib_classes.py

-#!/usr/bin/python
-
-# Copyright (c) 2009 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.
-
-# Usage: make_ib_classes.py output.mm input.xib [...]
-#
-# Generates an Objective-C++ file at output.mm referencing each class described
-# in input.xib.
-#
-# This script is useful when building an application containing .nib or .xib
-# files that reference Objective-C classes that may not be referenced by other
-# code in the application.  The intended use case is when the .nib and .xib
-# files refer to classes that are built into a static library that gets linked
-# into the main executable.  If nothing in the main executable references those
-# classes, the linker will not include them in its output (without -all_load or
-# -ObjC).  Using this script, references to such classes are created, such that

[Mark Mentovai, 2009/02/28 00:50:12]

See?

-# if output.mm is compiled into the application itself, it will provide the
-# class references and cause the linker to bring the required code into the
-# executable.
-#
-# If your application is structured in the above way, and you're plagued with
-# messages like:
-#   app[12345:101] Unknown class `MyApp' in nib file, using `NSObject' instead.
-# then this script may be right for you.
-
-
-import errno
-import os
-import os.path
-import re
-import subprocess
-import sys
-
-
-# Patterns used by ListIBClasses
-
-# A pattern that matches the line preceding a class name.
-_class_re = re.compile('<key>class</key>$')
-
-# A pattern that matches the line with a class name; match group 1 should be
-# the class name.
-_class_name_re = re.compile('<string>(.*)</string>$')
-
-# A pattern that matches class names to exclude from the output.  This includes
-# various Cocoa classes.
-_forbidden_class_re = re.compile('^(NS|IB|FirstResponder$|WebView$)')
-
-def ListIBClasses(ib_path, class_names=None):
-  """Returns a list of class names referenced by ib_path.
-
-  ib_path is a path to an Interface Builder document.  It may be a .nib or a
-  .xib.
-
-  This function calls "ibtool --classes" to get the list of class names.
-  ibtool's output is in XML plist format.  Rather than doing proper structured
-  plist scanning, this function relies on the fact that plists are serialized
-  to XML in a consistent way, and simply takes the string value names of any
-  dictionary key named "class" as class names.
-
-  class_names may be specified as an existing list to use.  This is helpful
-  when this function will be called several times for multiple nib/xib files.
-  """
-  if class_names == None:
-    class_names = []
-
-  # When running within an Xcode build, use the tools from that Xcode
-  # installation.
-  developer_tools_dir = os.getenv('DEVELOPER_BIN_DIR', '/usr/bin')
-  ibtool_path = os.path.join(developer_tools_dir, 'ibtool')
-  ibtool_command = [ibtool_path, '--classes', ib_path]
-
-  ibtool = subprocess.Popen(ibtool_command, stdout=subprocess.PIPE)
-
-  ibtool_output = ibtool.communicate()[0]
-
-  ibtool_rv = ibtool.returncode
-  assert ibtool_rv == 0
-
-  # Loop through the output, looking for "class" keys.  The string value on
-  # any line following a "class" key is taken as a class name.
-  is_class_name = False
-  for line in ibtool_output.splitlines():
-    if is_class_name:
-      class_name = _class_name_re.search(line).group(1)
-      is_class_name = False
-      if not class_name in class_names and \
-         not _forbidden_class_re.search(class_name):
-        class_names.append(class_name)
-    elif _class_re.search(line):
-      is_class_name = True
-
-  return class_names
-
-
-def main(args):
-  assert len(args) > 2
-  (script_path, output_path) = args[0:2]
-  assert output_path.endswith('.mm')
-  input_paths = args[2:]
-
-  try:
-    os.unlink(output_path)
-  except OSError, e:
-    if e.errno != errno.ENOENT:
-      raise
-
-  class_names = []
-
-  # Get the class names for all desired files.
-  for input_path in input_paths:
-    ListIBClasses(input_path, class_names)
-
-  class_names.sort()
-
-  # Write the requested output file.  Each class is referenced simply by
-  # calling its +class function.  In order to do this, each class needs a
-  # bogus @interface to tell the compiler that it's an NSObject subclass.
-  # #import NSObject.h to get the definition of NSObject without bringing in
-  # other headers that might provide real declarations.
-
-  output_file = open(output_path, 'w')
-  print >>output_file, \
-"""// This file was generated by %s.  Do not edit.
-
-#import <Foundation/NSObject.h>
-""" % os.path.basename(script_path)
-
-  for class_name in class_names:
-    print >>output_file, '@interface %s : NSObject\n@end' % class_name
-
-  print >>output_file, '\nnamespace {\n\nvoid IBClasses() {'
-
-  for class_name in class_names:
-    print >>output_file, '  [%s class];' % class_name
-
-  print >>output_file, '}\n\n}  // namespace'
-
-  output_file.close()
-
-  return 0
-
-
-if __name__ == '__main__':
-  sys.exit(main(sys.argv))