third_party/WebKit/Source/build/scripts/make_runtime_features.py

   1 #!/usr/bin/env python
   2 # Copyright (C) 2013 Google Inc. All rights reserved.
   3 #
   4 # Redistribution and use in source and binary forms, with or without
   5 # modification, are permitted provided that the following conditions are
   6 # met:
   7 #
   8 #     * Redistributions of source code must retain the above copyright
   9 # notice, this list of conditions and the following disclaimer.
  10 #     * Redistributions in binary form must reproduce the above
  11 # copyright notice, this list of conditions and the following disclaimer
  12 # in the documentation and/or other materials provided with the
  13 # distribution.
  14 #     * Neither the name of Google Inc. nor the names of its
  15 # contributors may be used to endorse or promote products derived from
  16 # this software without specific prior written permission.
  17 #
  18 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29
  30 import sys
  31
  32 import in_generator
  33 import name_utilities
  34 from name_utilities import lower_first
  35 import template_expander
  36
  37
  38 class RuntimeFeatureWriter(in_generator.Writer):
  39     class_name = 'RuntimeEnabledFeatures'
  40     filters = {
  41         'enable_conditional': name_utilities.enable_conditional_if_endif,
  42     }
  43
  44     # FIXME: valid_values and defaults should probably roll into one object.
  45     valid_values = {
  46         'status': ['stable', 'experimental', 'test', 'deprecated'],
  47     }
  48     defaults = {
  49         'condition': None,
  50         'implied_by': [],
  51         'depends_on': [],
  52         'custom': False,
  53         'status': None,
  54     }
  55
  56     _status_aliases = {
  57         'deprecated': 'test',
  58     }
  59
  60     def __init__(self, in_file_path):
  61         super(RuntimeFeatureWriter, self).__init__(in_file_path)
  62         self._outputs = {(self.class_name + '.h'): self.generate_header,
  63                          (self.class_name + '.cpp'): self.generate_implementation,
  64                         }
  65
  66         self._features = self.in_file.name_dictionaries
  67         # Make sure the resulting dictionaries have all the keys we expect.
  68         for feature in self._features:
  69             feature['first_lowered_name'] = lower_first(feature['name'])
  70             feature['status'] = self._status_aliases.get(feature['status'], feature['status'])
  71             # Most features just check their isFooEnabled bool
  72             # but some depend on or are implied by other bools.
  73             enabled_condition = 'is%sEnabled' % feature['name']
  74             assert not feature['implied_by'] or not feature['depends_on'], 'Only one of implied_by and depends_on is allowed'
  75             for implied_by_name in feature['implied_by']:
  76                 enabled_condition += ' || is%sEnabled' % implied_by_name
  77             for dependant_name in feature['depends_on']:
  78                 enabled_condition += ' && is%sEnabled' % dependant_name
  79             feature['enabled_condition'] = enabled_condition
  80         self._non_custom_features = filter(lambda feature: not feature['custom'], self._features)
  81
  82     def _feature_sets(self):
  83         # Another way to think of the status levels is as "sets of features"
  84         # which is how we're referring to them in this generator.
  85         return [status for status in self.valid_values['status'] if status not in self._status_aliases]
  86
  87     @template_expander.use_jinja(class_name + '.h.tmpl', filters=filters)
  88     def generate_header(self):
  89         return {
  90             'features': self._features,
  91             'feature_sets': self._feature_sets(),
  92         }
  93
  94     @template_expander.use_jinja(class_name + '.cpp.tmpl', filters=filters)
  95     def generate_implementation(self):
  96         return {
  97             'features': self._features,
  98             'feature_sets': self._feature_sets(),
  99         }
 100
 101
 102 if __name__ == '__main__':
 103     in_generator.Maker(RuntimeFeatureWriter).main(sys.argv)