tools/json_schema_compiler/cpp_bundle_generator.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import code
   6 import cpp_util
   7 from model import Platforms
   8 from schema_util import CapitalizeFirstLetter
   9 from schema_util import JsFunctionNameToClassName
  10
  11 import json
  12 import os
  13 import re
  14
  15
  16 def _RemoveDescriptions(node):
  17   """Returns a copy of |schema| with "description" fields removed.
  18   """
  19   if isinstance(node, dict):
  20     result = {}
  21     for key, value in node.items():
  22       # Some schemas actually have properties called "description", so only
  23       # remove descriptions that have string values.
  24       if key == 'description' and isinstance(value, basestring):
  25         continue
  26       result[key] = _RemoveDescriptions(value)
  27     return result
  28   if isinstance(node, list):
  29     return [_RemoveDescriptions(v) for v in node]
  30   return node
  31
  32
  33 class CppBundleGenerator(object):
  34   """This class contains methods to generate code based on multiple schemas.
  35   """
  36
  37   def __init__(self,
  38                root,
  39                model,
  40                api_defs,
  41                cpp_type_generator,
  42                cpp_namespace_pattern,
  43                source_file_dir,
  44                impl_dir):
  45     self._root = root
  46     self._model = model
  47     self._api_defs = api_defs
  48     self._cpp_type_generator = cpp_type_generator
  49     self._source_file_dir = source_file_dir
  50     self._impl_dir = impl_dir
  51
  52     # Hack: assume that the C++ namespace for the bundle is the namespace of the
  53     # files without the last component of the namespace. A cleaner way to do
  54     # this would be to make it a separate variable in the gyp file.
  55     self._cpp_namespace = cpp_namespace_pattern.rsplit('::', 1)[0]
  56
  57     self.api_cc_generator = _APICCGenerator(self)
  58     self.api_h_generator = _APIHGenerator(self)
  59     self.schemas_cc_generator = _SchemasCCGenerator(self)
  60     self.schemas_h_generator = _SchemasHGenerator(self)
  61
  62   def _GenerateHeader(self, file_base, body_code):
  63     """Generates a code.Code object for a header file
  64
  65     Parameters:
  66     - |file_base| - the base of the filename, e.g. 'foo' (for 'foo.h')
  67     - |body_code| - the code to put in between the multiple inclusion guards"""
  68     c = code.Code()
  69     c.Append(cpp_util.CHROMIUM_LICENSE)
  70     c.Append()
  71     c.Append(cpp_util.GENERATED_BUNDLE_FILE_MESSAGE % self._source_file_dir)
  72     ifndef_name = cpp_util.GenerateIfndefName(
  73         '%s/%s.h' % (self._source_file_dir, file_base))
  74     c.Append()
  75     c.Append('#ifndef %s' % ifndef_name)
  76     c.Append('#define %s' % ifndef_name)
  77     c.Append()
  78     c.Concat(body_code)
  79     c.Append()
  80     c.Append('#endif  // %s' % ifndef_name)
  81     c.Append()
  82     return c
  83
  84   def _GetPlatformIfdefs(self, model_object):
  85     """Generates the "defined" conditional for an #if check if |model_object|
  86     has platform restrictions. Returns None if there are no restrictions.
  87     """
  88     if model_object.platforms is None:
  89       return None
  90     ifdefs = []
  91     for platform in model_object.platforms:
  92       if platform == Platforms.CHROMEOS:
  93         ifdefs.append('defined(OS_CHROMEOS)')
  94       elif platform == Platforms.LINUX:
  95         ifdefs.append('defined(OS_LINUX)')
  96       elif platform == Platforms.MAC:
  97         ifdefs.append('defined(OS_MACOSX)')
  98       elif platform == Platforms.WIN:
  99         ifdefs.append('defined(OS_WIN)')
 100       else:
 101         raise ValueError("Unsupported platform ifdef: %s" % platform.name)
 102     return ' || '.join(ifdefs)
 103
 104   def _GenerateRegisterFunctions(self, namespace_name, function):
 105     c = code.Code()
 106     function_ifdefs = self._GetPlatformIfdefs(function)
 107     if function_ifdefs is not None:
 108       c.Append("#if %s" % function_ifdefs, indent_level=0)
 109
 110     function_name = JsFunctionNameToClassName(namespace_name, function.name)
 111     c.Append("registry->RegisterFunction<%sFunction>();" % (
 112         function_name))
 113
 114     if function_ifdefs is not None:
 115       c.Append("#endif  // %s" % function_ifdefs, indent_level=0)
 116     return c
 117
 118   def _GenerateFunctionRegistryRegisterAll(self):
 119     c = code.Code()
 120     c.Append('// static')
 121     c.Sblock('void GeneratedFunctionRegistry::RegisterAll('
 122                  'ExtensionFunctionRegistry* registry) {')
 123     for namespace in self._model.namespaces.values():
 124       namespace_ifdefs = self._GetPlatformIfdefs(namespace)
 125       if namespace_ifdefs is not None:
 126         c.Append("#if %s" % namespace_ifdefs, indent_level=0)
 127
 128       namespace_name = CapitalizeFirstLetter(namespace.name.replace(
 129           "experimental.", ""))
 130       for function in namespace.functions.values():
 131         if function.nocompile:
 132           continue
 133         c.Concat(self._GenerateRegisterFunctions(namespace.name, function))
 134
 135       for type_ in namespace.types.values():
 136         for function in type_.functions.values():
 137           if function.nocompile:
 138             continue
 139           namespace_types_name = JsFunctionNameToClassName(
 140                 namespace.name, type_.name)
 141           c.Concat(self._GenerateRegisterFunctions(namespace_types_name,
 142                                                    function))
 143
 144       if namespace_ifdefs is not None:
 145         c.Append("#endif  // %s" % namespace_ifdefs, indent_level=0)
 146     c.Eblock("}")
 147     return c
 148
 149
 150 class _APIHGenerator(object):
 151   """Generates the header for API registration / declaration"""
 152   def __init__(self, cpp_bundle):
 153     self._bundle = cpp_bundle
 154
 155   def Generate(self, _):  # namespace not relevant, this is a bundle
 156     c = code.Code()
 157
 158     c.Append('#include <string>')
 159     c.Append()
 160     c.Append('#include "base/basictypes.h"')
 161     c.Append()
 162     c.Append("class ExtensionFunctionRegistry;")
 163     c.Append()
 164     c.Concat(cpp_util.OpenNamespace(self._bundle._cpp_namespace))
 165     c.Append()
 166     c.Append('class GeneratedFunctionRegistry {')
 167     c.Sblock(' public:')
 168     c.Append('static void RegisterAll('
 169                  'ExtensionFunctionRegistry* registry);')
 170     c.Eblock('};')
 171     c.Append()
 172     c.Concat(cpp_util.CloseNamespace(self._bundle._cpp_namespace))
 173     return self._bundle._GenerateHeader('generated_api', c)
 174
 175
 176 class _APICCGenerator(object):
 177   """Generates a code.Code object for the generated API .cc file"""
 178
 179   def __init__(self, cpp_bundle):
 180     self._bundle = cpp_bundle
 181
 182   def Generate(self, _):  # namespace not relevant, this is a bundle
 183     c = code.Code()
 184     c.Append(cpp_util.CHROMIUM_LICENSE)
 185     c.Append()
 186     c.Append('#include "%s"' % (
 187         os.path.join(self._bundle._impl_dir,
 188                      'generated_api_registration.h')))
 189     c.Append()
 190     for namespace in self._bundle._model.namespaces.values():
 191       namespace_name = namespace.unix_name.replace("experimental_", "")
 192       implementation_header = namespace.compiler_options.get(
 193           "implemented_in",
 194           "%s/%s/%s_api.h" % (self._bundle._impl_dir,
 195                               namespace_name,
 196                               namespace_name))
 197       if not os.path.exists(
 198           os.path.join(self._bundle._root,
 199                        os.path.normpath(implementation_header))):
 200         if "implemented_in" in namespace.compiler_options:
 201           raise ValueError('Header file for namespace "%s" specified in '
 202                           'compiler_options not found: %s' %
 203                           (namespace.unix_name, implementation_header))
 204         continue
 205       ifdefs = self._bundle._GetPlatformIfdefs(namespace)
 206       if ifdefs is not None:
 207         c.Append("#if %s" % ifdefs, indent_level=0)
 208
 209       c.Append('#include "%s"' % implementation_header)
 210
 211       if ifdefs is not None:
 212         c.Append("#endif  // %s" % ifdefs, indent_level=0)
 213     c.Append()
 214     c.Append('#include '
 215                  '"extensions/browser/extension_function_registry.h"')
 216     c.Append()
 217     c.Concat(cpp_util.OpenNamespace(self._bundle._cpp_namespace))
 218     c.Append()
 219     c.Concat(self._bundle._GenerateFunctionRegistryRegisterAll())
 220     c.Append()
 221     c.Concat(cpp_util.CloseNamespace(self._bundle._cpp_namespace))
 222     c.Append()
 223     return c
 224
 225
 226 class _SchemasHGenerator(object):
 227   """Generates a code.Code object for the generated schemas .h file"""
 228   def __init__(self, cpp_bundle):
 229     self._bundle = cpp_bundle
 230
 231   def Generate(self, _):  # namespace not relevant, this is a bundle
 232     c = code.Code()
 233     c.Append('#include <map>')
 234     c.Append('#include <string>')
 235     c.Append()
 236     c.Append('#include "base/strings/string_piece.h"')
 237     c.Append()
 238     c.Concat(cpp_util.OpenNamespace(self._bundle._cpp_namespace))
 239     c.Append()
 240     c.Append('class GeneratedSchemas {')
 241     c.Sblock(' public:')
 242     c.Append('// Determines if schema named |name| is generated.')
 243     c.Append('static bool IsGenerated(std::string name);')
 244     c.Append()
 245     c.Append('// Gets the API schema named |name|.')
 246     c.Append('static base::StringPiece Get(const std::string& name);')
 247     c.Eblock('};')
 248     c.Append()
 249     c.Concat(cpp_util.CloseNamespace(self._bundle._cpp_namespace))
 250     return self._bundle._GenerateHeader('generated_schemas', c)
 251
 252
 253 def _FormatNameAsConstant(name):
 254   """Formats a name to be a C++ constant of the form kConstantName"""
 255   name = '%s%s' % (name[0].upper(), name[1:])
 256   return 'k%s' % re.sub('_[a-z]',
 257                         lambda m: m.group(0)[1].upper(),
 258                         name.replace('.', '_'))
 259
 260
 261 class _SchemasCCGenerator(object):
 262   """Generates a code.Code object for the generated schemas .cc file"""
 263
 264   def __init__(self, cpp_bundle):
 265     self._bundle = cpp_bundle
 266
 267   def Generate(self, _):  # namespace not relevant, this is a bundle
 268     c = code.Code()
 269     c.Append(cpp_util.CHROMIUM_LICENSE)
 270     c.Append()
 271     c.Append('#include "%s"' % (os.path.join(self._bundle._source_file_dir,
 272                                              'generated_schemas.h')))
 273     c.Append()
 274     c.Append('#include "base/lazy_instance.h"')
 275     c.Append()
 276     c.Append('namespace {')
 277     for api in self._bundle._api_defs:
 278       namespace = self._bundle._model.namespaces[api.get('namespace')]
 279       # JSON parsing code expects lists of schemas, so dump a singleton list.
 280       json_content = json.dumps([_RemoveDescriptions(api)],
 281                                 separators=(',', ':'))
 282       # Escape all double-quotes and backslashes. For this to output a valid
 283       # JSON C string, we need to escape \ and ". Note that some schemas are
 284       # too large to compile on windows. Split the JSON up into several
 285       # strings, since apparently that helps.
 286       max_length = 8192
 287       segments = [json_content[i:i + max_length].replace('\\', '\\\\')
 288                                                 .replace('"', '\\"')
 289                   for i in xrange(0, len(json_content), max_length)]
 290       c.Append('const char %s[] = "%s";' %
 291           (_FormatNameAsConstant(namespace.name), '" "'.join(segments)))
 292     c.Append('}')
 293     c.Concat(cpp_util.OpenNamespace(self._bundle._cpp_namespace))
 294     c.Append()
 295     c.Sblock('struct Static {')
 296     c.Sblock('Static() {')
 297     for api in self._bundle._api_defs:
 298       namespace = self._bundle._model.namespaces[api.get('namespace')]
 299       c.Append('schemas["%s"] = %s;' % (namespace.name,
 300                                         _FormatNameAsConstant(namespace.name)))
 301     c.Eblock('}')
 302     c.Append()
 303     c.Append('std::map<std::string, const char*> schemas;')
 304     c.Eblock('};')
 305     c.Append()
 306     c.Append('base::LazyInstance<Static> g_lazy_instance;')
 307     c.Append()
 308     c.Append('// static')
 309     c.Sblock('base::StringPiece GeneratedSchemas::Get('
 310                   'const std::string& name) {')
 311     c.Append('return IsGenerated(name) ? '
 312              'g_lazy_instance.Get().schemas[name] : "";')
 313     c.Eblock('}')
 314     c.Append()
 315     c.Append('// static')
 316     c.Sblock('bool GeneratedSchemas::IsGenerated(std::string name) {')
 317     c.Append('return g_lazy_instance.Get().schemas.count(name) > 0;')
 318     c.Eblock('}')
 319     c.Append()
 320     c.Concat(cpp_util.CloseNamespace(self._bundle._cpp_namespace))
 321     c.Append()
 322     return c