IDL compiler: Pickle interface information

Source/bindings/scripts/compute_dependencies.py

 #!/usr/bin/python
 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
@@ skipping 12 matching lines @@
 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import optparse
 import os
+import cPickle as pickle
 import posixpath
 import re
 import string
 
 
 class IdlBadFilenameError(Exception):
     """Raised if an IDL filename disagrees with the interface name in the file."""
     pass
 
 
 class IdlInterfaceFileNotFoundError(Exception):
     """Raised if the IDL file implementing an interface cannot be found."""
     pass
 
 
 def parse_options():
     parser = optparse.OptionParser()
     parser.add_option('--event-names-file', help='output file')
     parser.add_option('--main-idl-files-list', help='file listing main (compiled to Blink) IDL files')
     parser.add_option('--support-idl-files-list', help='file listing support IDL files (not compiled to Blink, e.g. testing)')
     parser.add_option('--interface-dependencies-file', help='output file')
+    parser.add_option('--interfaces-info-file', help='output pickle file')
     parser.add_option('--bindings-derived-sources-file', help='output file')
     parser.add_option('--window-constructors-file', help='output file')
     parser.add_option('--workerglobalscope-constructors-file', help='output file')
     parser.add_option('--sharedworkerglobalscope-constructors-file', help='output file')
     parser.add_option('--dedicatedworkerglobalscope-constructors-file', help='output file')
     parser.add_option('--serviceworkerglobalscope-constructors-file', help='output file')
     parser.add_option('--write-file-only-if-changed', type='int', help='if true, do not write an output file if it would be identical to the existing one, which avoids unnecessary rebuilds in ninja')
     options, args = parser.parse_args()
     if options.event_names_file is None:
         parser.error('Must specify an output file using --event-names-file.')
     if options.interface_dependencies_file is None:
         parser.error('Must specify an output file using --interface-dependencies-file.')
+    if options.interfaces_info_file is None:
+        parser.error('Must specify an output file using --interfaces-info-file.')
     if options.bindings_derived_sources_file is None:
         parser.error('Must specify an output file using --bindings-derived-sources-file.')
     if options.window_constructors_file is None:
         parser.error('Must specify an output file using --window-constructors-file.')
     if options.workerglobalscope_constructors_file is None:
         parser.error('Must specify an output file using --workerglobalscope-constructors-file.')
     if options.sharedworkerglobalscope_constructors_file is None:
         parser.error('Must specify an output file using --sharedworkerglobalscope-constructors-file.')
     if options.dedicatedworkerglobalscope_constructors_file is None:
         parser.error('Must specify an output file using --dedicatedworkerglobalscope-constructors-file.')
@@ skipping 269 matching lines @@
         event_names[interface_name_to_idl_file['Event']] = interface_extended_attribute['Event']
     for interface, parent in parent_interface.iteritems():
         while parent in parent_interface:
             parent = parent_interface[parent]
         if parent == 'Event':
             event_names[interface_name_to_idl_file[interface]] = interface_extended_attribute[interface]
 
     return interfaces, dependencies, bindings_derived_sources, global_constructors, event_names
 
 
-def write_dependency_file(filename, dependencies, only_if_changed):
+def write_dependency_file(dependencies_filename, interfaces_info_filename, dependencies, only_if_changed):
     """Write the interface dependencies file.
 
     The format is as follows:
 
     Document.idl P.idl
     Event.idl
     Window.idl Q.idl R.idl S.idl
     ...
 
     The above indicates that:
     Document.idl depends on P.idl,
     Event.idl depends on no other IDL files, and
     Window.idl depends on Q.idl, R.idl, and S.idl.
 
     An IDL that is a dependency of another IDL (e.g. P.idl) does not have its
     own line in the dependency file.
     """
+    # FIXME: remove text format once Perl gone (Python uses pickle)
     lines = ['%s %s\n' % (idl_file, ' '.join(sorted(dependency_files)))
              for idl_file, dependency_files in sorted(dependencies.iteritems())]
-    write_file(lines, filename, only_if_changed)
+    write_file(lines, dependencies_filename, only_if_changed)
+
+    if not interfaces_info_filename:
+        return
+    interfaces = {}
+    for idl_filename, dependency_files in dependencies.iteritems():
+        idl_basename = os.path.basename(idl_filename)
+        interface_name, _ = os.path.splitext(idl_basename)
+        interfaces[interface_name] = dependency_files
+
+    if only_if_changed and os.path.isfile(interfaces_info_filename):
+        with open(interfaces_info_filename, 'r+') as pickle_file:
+            if pickle.load(pickle_file) == interfaces:
+                return
+            pickle_file.seek(0)
+            pickle.dump(interfaces, pickle_file)
+        return
+    with open(interfaces_info_filename, 'w') as pickle_file:
+        pickle.dump(interfaces, pickle_file)
 
 
 def main():
     options = parse_options()
     with open(options.main_idl_files_list) as idl_files_list:
         main_idl_files = [string.rstrip(line, '\n') for line in idl_files_list]
     with open(options.support_idl_files_list) as idl_files_list:
         support_idl_files = [string.rstrip(line, '\n') for line in idl_files_list]
     only_if_changed = options.write_file_only_if_changed
     global_constructors_filenames = {
         'Window': options.window_constructors_file,
         'WorkerGlobalScope': options.workerglobalscope_constructors_file,
         'SharedWorkerGlobalScope': options.sharedworkerglobalscope_constructors_file,
         'DedicatedWorkerGlobalScope': options.dedicatedworkerglobalscope_constructors_file,
         'ServiceWorkerGlobalScope': options.serviceworkerglobalscope_constructors_file,
         }
 
     interfaces, dependencies, bindings_derived_sources, global_constructors, event_names = parse_idl_files(main_idl_files, support_idl_files, global_constructors_filenames)
 
-    write_dependency_file(options.interface_dependencies_file, dependencies, only_if_changed)
-    write_dependency_file(options.bindings_derived_sources_file, bindings_derived_sources, only_if_changed)
+    write_dependency_file(options.interface_dependencies_file, options.interfaces_info_file, dependencies, only_if_changed)
+    write_dependency_file(options.bindings_derived_sources_file, None, bindings_derived_sources, only_if_changed)
     for interface_name, filename in global_constructors_filenames.iteritems():
         if interface_name in interfaces:
             generate_global_constructors_partial_interface(interface_name, filename, global_constructors[interface_name], only_if_changed)
     generate_event_names_file(options.event_names_file, event_names, only_if_changed)
 
 
 if __name__ == '__main__':
     main()