cc_generator.py revision 5c02ac1a9c1b504631c0a3d2b6e737b5d738bae1
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
5from code import Code
6from model import PropertyType
7import cpp_util
8import schema_util
9import util_cc_helper
10
11class CCGenerator(object):
12  def __init__(self, type_generator, cpp_namespace):
13    self._type_generator = type_generator
14    self._cpp_namespace = cpp_namespace
15
16  def Generate(self, namespace):
17    return _Generator(namespace,
18                      self._type_generator,
19                      self._cpp_namespace).Generate()
20
21
22class _Generator(object):
23  """A .cc generator for a namespace.
24  """
25  def __init__(self, namespace, cpp_type_generator, cpp_namespace):
26    self._namespace = namespace
27    self._type_helper = cpp_type_generator
28    self._cpp_namespace = cpp_namespace
29    self._target_namespace = (
30        self._type_helper.GetCppNamespaceName(self._namespace))
31    self._util_cc_helper = (
32        util_cc_helper.UtilCCHelper(self._type_helper))
33    self._generate_error_messages = namespace.compiler_options.get(
34        'generate_error_messages', False)
35
36  def Generate(self):
37    """Generates a Code object with the .cc for a single namespace.
38    """
39    c = Code()
40    (c.Append(cpp_util.CHROMIUM_LICENSE)
41      .Append()
42      .Append(cpp_util.GENERATED_FILE_MESSAGE % self._namespace.source_file)
43      .Append()
44      .Append(self._util_cc_helper.GetIncludePath())
45      .Append('#include "base/logging.h"')
46      .Append('#include "base/strings/string_number_conversions.h"')
47      .Append('#include "base/strings/utf_string_conversions.h"')
48      .Append('#include "%s/%s.h"' %
49              (self._namespace.source_file_dir, self._namespace.short_filename))
50      .Append('#include <set>')
51      .Cblock(self._type_helper.GenerateIncludes(include_soft=True))
52      .Append()
53      .Append('using base::UTF8ToUTF16;')
54      .Append()
55      .Concat(cpp_util.OpenNamespace(self._cpp_namespace))
56      .Cblock(self._type_helper.GetNamespaceStart())
57    )
58    if self._namespace.properties:
59      (c.Append('//')
60        .Append('// Properties')
61        .Append('//')
62        .Append()
63      )
64      for property in self._namespace.properties.values():
65        property_code = self._type_helper.GeneratePropertyValues(
66            property,
67            'const %(type)s %(name)s = %(value)s;',
68            nodoc=True)
69        if property_code:
70          c.Cblock(property_code)
71    if self._namespace.types:
72      (c.Append('//')
73        .Append('// Types')
74        .Append('//')
75        .Append()
76        .Cblock(self._GenerateTypes(None, self._namespace.types.values()))
77      )
78    if self._namespace.functions:
79      (c.Append('//')
80        .Append('// Functions')
81        .Append('//')
82        .Append()
83      )
84    for function in self._namespace.functions.values():
85      c.Cblock(self._GenerateFunction(function))
86    if self._namespace.events:
87      (c.Append('//')
88        .Append('// Events')
89        .Append('//')
90        .Append()
91      )
92      for event in self._namespace.events.values():
93        c.Cblock(self._GenerateEvent(event))
94    (c.Concat(self._type_helper.GetNamespaceEnd())
95      .Cblock(cpp_util.CloseNamespace(self._cpp_namespace))
96    )
97    c.Append()
98    return c
99
100  def _GenerateType(self, cpp_namespace, type_):
101    """Generates the function definitions for a type.
102    """
103    classname = cpp_util.Classname(schema_util.StripNamespace(type_.name))
104    c = Code()
105
106    if type_.functions:
107      # Wrap functions within types in the type's namespace.
108      (c.Append('namespace %s {' % classname)
109        .Append())
110      for function in type_.functions.values():
111        c.Cblock(self._GenerateFunction(function))
112      c.Append('}  // namespace %s' % classname)
113    elif type_.property_type == PropertyType.ARRAY:
114      c.Cblock(self._GenerateType(cpp_namespace, type_.item_type))
115    elif type_.property_type in (PropertyType.CHOICES,
116                                 PropertyType.OBJECT):
117      if cpp_namespace is None:
118        classname_in_namespace = classname
119      else:
120        classname_in_namespace = '%s::%s' % (cpp_namespace, classname)
121
122      if type_.property_type == PropertyType.OBJECT:
123        c.Cblock(self._GeneratePropertyFunctions(classname_in_namespace,
124                                                 type_.properties.values()))
125      else:
126        c.Cblock(self._GenerateTypes(classname_in_namespace, type_.choices))
127
128      (c.Append('%s::%s()' % (classname_in_namespace, classname))
129        .Cblock(self._GenerateInitializersAndBody(type_))
130        .Append('%s::~%s() {}' % (classname_in_namespace, classname))
131        .Append()
132      )
133      if type_.origin.from_json:
134        c.Cblock(self._GenerateTypePopulate(classname_in_namespace, type_))
135        if cpp_namespace is None:  # only generate for top-level types
136          c.Cblock(self._GenerateTypeFromValue(classname_in_namespace, type_))
137      if type_.origin.from_client:
138        c.Cblock(self._GenerateTypeToValue(classname_in_namespace, type_))
139    elif type_.property_type == PropertyType.ENUM:
140      (c.Cblock(self._GenerateEnumToString(cpp_namespace, type_))
141        .Cblock(self._GenerateEnumFromString(cpp_namespace, type_))
142      )
143
144    return c
145
146  def _GenerateInitializersAndBody(self, type_):
147    items = []
148    for prop in type_.properties.values():
149      if prop.optional:
150        continue
151
152      t = prop.type_
153      if t.property_type == PropertyType.INTEGER:
154        items.append('%s(0)' % prop.unix_name)
155      elif t.property_type == PropertyType.DOUBLE:
156        items.append('%s(0.0)' % prop.unix_name)
157      elif t.property_type == PropertyType.BOOLEAN:
158        items.append('%s(false)' % prop.unix_name)
159      elif (t.property_type == PropertyType.ANY or
160            t.property_type == PropertyType.ARRAY or
161            t.property_type == PropertyType.BINARY or  # mapped to std::string
162            t.property_type == PropertyType.CHOICES or
163            t.property_type == PropertyType.ENUM or
164            t.property_type == PropertyType.OBJECT or
165            t.property_type == PropertyType.FUNCTION or
166            t.property_type == PropertyType.REF or
167            t.property_type == PropertyType.STRING):
168        # TODO(miket): It would be nice to initialize CHOICES and ENUM, but we
169        # don't presently have the semantics to indicate which one of a set
170        # should be the default.
171        continue
172      else:
173        raise TypeError(t)
174
175    if items:
176      s = ': %s' % (', '.join(items))
177    else:
178      s = ''
179    s = s + ' {}'
180    return Code().Append(s)
181
182  def _GenerateTypePopulate(self, cpp_namespace, type_):
183    """Generates the function for populating a type given a pointer to it.
184
185    E.g for type "Foo", generates Foo::Populate()
186    """
187    classname = cpp_util.Classname(schema_util.StripNamespace(type_.name))
188    c = Code()
189    (c.Append('// static')
190      .Append('bool %(namespace)s::Populate(')
191      .Sblock('    %s) {' % self._GenerateParams(
192          ('const base::Value& value', '%(name)s* out'))))
193
194    if type_.property_type == PropertyType.CHOICES:
195      for choice in type_.choices:
196        (c.Sblock('if (%s) {' % self._GenerateValueIsTypeExpression('value',
197                                                                    choice))
198            .Concat(self._GeneratePopulateVariableFromValue(
199                choice,
200                '(&value)',
201                'out->as_%s' % choice.unix_name,
202                'false',
203                is_ptr=True))
204            .Append('return true;')
205          .Eblock('}')
206        )
207      (c.Concat(self._GenerateError(
208          '"expected %s, got " +  %s' %
209              (" or ".join(choice.name for choice in type_.choices),
210              self._util_cc_helper.GetValueTypeString('value'))))
211        .Append('return false;'))
212    elif type_.property_type == PropertyType.OBJECT:
213      (c.Sblock('if (!value.IsType(base::Value::TYPE_DICTIONARY)) {')
214        .Concat(self._GenerateError(
215          '"expected dictionary, got " + ' +
216          self._util_cc_helper.GetValueTypeString('value')))
217        .Append('return false;')
218        .Eblock('}'))
219
220      if type_.properties or type_.additional_properties is not None:
221        c.Append('const base::DictionaryValue* dict = '
222                     'static_cast<const base::DictionaryValue*>(&value);')
223        if self._generate_error_messages:
224            c.Append('std::set<std::string> keys;')
225      for prop in type_.properties.itervalues():
226        c.Concat(self._InitializePropertyToDefault(prop, 'out'))
227      for prop in type_.properties.itervalues():
228        if self._generate_error_messages:
229          c.Append('keys.insert("%s");' % (prop.name))
230        c.Concat(self._GenerateTypePopulateProperty(prop, 'dict', 'out'))
231      # Check for extra values.
232      if self._generate_error_messages:
233        (c.Sblock('for (base::DictionaryValue::Iterator it(*dict); '
234                       '!it.IsAtEnd(); it.Advance()) {')
235          .Sblock('if (!keys.count(it.key())) {')
236          .Concat(self._GenerateError('"found unexpected key \'" + '
237                                          'it.key() + "\'"'))
238          .Eblock('}')
239          .Eblock('}')
240        )
241      if type_.additional_properties is not None:
242        if type_.additional_properties.property_type == PropertyType.ANY:
243          c.Append('out->additional_properties.MergeDictionary(dict);')
244        else:
245          cpp_type = self._type_helper.GetCppType(type_.additional_properties,
246                                                  is_in_container=True)
247          (c.Append('for (base::DictionaryValue::Iterator it(*dict);')
248            .Sblock('     !it.IsAtEnd(); it.Advance()) {')
249              .Append('%s tmp;' % cpp_type)
250              .Concat(self._GeneratePopulateVariableFromValue(
251                  type_.additional_properties,
252                  '(&it.value())',
253                  'tmp',
254                  'false'))
255              .Append('out->additional_properties[it.key()] = tmp;')
256            .Eblock('}')
257          )
258      c.Append('return true;')
259    (c.Eblock('}')
260      .Substitute({'namespace': cpp_namespace, 'name': classname}))
261    return c
262
263  def _GenerateValueIsTypeExpression(self, var, type_):
264    real_type = self._type_helper.FollowRef(type_)
265    if real_type.property_type is PropertyType.CHOICES:
266      return '(%s)' % ' || '.join(self._GenerateValueIsTypeExpression(var,
267                                                                      choice)
268                                  for choice in real_type.choices)
269    return '%s.IsType(%s)' % (var, cpp_util.GetValueType(real_type))
270
271  def _GenerateTypePopulateProperty(self, prop, src, dst):
272    """Generate the code to populate a single property in a type.
273
274    src: base::DictionaryValue*
275    dst: Type*
276    """
277    c = Code()
278    value_var = prop.unix_name + '_value'
279    c.Append('const base::Value* %(value_var)s = NULL;')
280    if prop.optional:
281      (c.Sblock(
282          'if (%(src)s->GetWithoutPathExpansion("%(key)s", &%(value_var)s)) {')
283        .Concat(self._GeneratePopulatePropertyFromValue(
284            prop, value_var, dst, 'false')))
285      underlying_type = self._type_helper.FollowRef(prop.type_)
286      if underlying_type.property_type == PropertyType.ENUM:
287        (c.Append('} else {')
288          .Append('%%(dst)s->%%(name)s = %s;' %
289              self._type_helper.GetEnumNoneValue(prop.type_)))
290      c.Eblock('}')
291    else:
292      (c.Sblock(
293          'if (!%(src)s->GetWithoutPathExpansion("%(key)s", &%(value_var)s)) {')
294        .Concat(self._GenerateError('"\'%%(key)s\' is required"'))
295        .Append('return false;')
296        .Eblock('}')
297        .Concat(self._GeneratePopulatePropertyFromValue(
298            prop, value_var, dst, 'false'))
299      )
300    c.Append()
301    c.Substitute({
302      'value_var': value_var,
303      'key': prop.name,
304      'src': src,
305      'dst': dst,
306      'name': prop.unix_name
307    })
308    return c
309
310  def _GenerateTypeFromValue(self, cpp_namespace, type_):
311    classname = cpp_util.Classname(schema_util.StripNamespace(type_.name))
312    c = Code()
313    (c.Append('// static')
314      .Append('scoped_ptr<%s> %s::FromValue(%s) {' % (classname,
315        cpp_namespace, self._GenerateParams(('const base::Value& value',))))
316      .Append('  scoped_ptr<%s> out(new %s());' % (classname, classname))
317      .Append('  if (!Populate(%s))' % self._GenerateArgs(
318          ('value', 'out.get()')))
319      .Append('    return scoped_ptr<%s>();' % classname)
320      .Append('  return out.Pass();')
321      .Append('}')
322    )
323    return c
324
325  def _GenerateTypeToValue(self, cpp_namespace, type_):
326    """Generates a function that serializes the type into a base::Value.
327    E.g. for type "Foo" generates Foo::ToValue()
328    """
329    if type_.property_type == PropertyType.OBJECT:
330      return self._GenerateObjectTypeToValue(cpp_namespace, type_)
331    elif type_.property_type == PropertyType.CHOICES:
332      return self._GenerateChoiceTypeToValue(cpp_namespace, type_)
333    else:
334      raise ValueError("Unsupported property type %s" % type_.type_)
335
336  def _GenerateObjectTypeToValue(self, cpp_namespace, type_):
337    """Generates a function that serializes an object-representing type
338    into a base::DictionaryValue.
339    """
340    c = Code()
341    (c.Sblock('scoped_ptr<base::DictionaryValue> %s::ToValue() const {' %
342          cpp_namespace)
343        .Append('scoped_ptr<base::DictionaryValue> value('
344                    'new base::DictionaryValue());')
345        .Append()
346    )
347
348    for prop in type_.properties.values():
349      prop_var = 'this->%s' % prop.unix_name
350      if prop.optional:
351        # Optional enum values are generated with a NONE enum value.
352        underlying_type = self._type_helper.FollowRef(prop.type_)
353        if underlying_type.property_type == PropertyType.ENUM:
354          c.Sblock('if (%s != %s) {' %
355              (prop_var,
356               self._type_helper.GetEnumNoneValue(prop.type_)))
357        else:
358          c.Sblock('if (%s.get()) {' % prop_var)
359
360      # ANY is a base::Value which is abstract and cannot be a direct member, so
361      # it will always be a pointer.
362      is_ptr = prop.optional or prop.type_.property_type == PropertyType.ANY
363      c.Append('value->SetWithoutPathExpansion("%s", %s);' % (
364          prop.name,
365          self._CreateValueFromType(prop.type_, prop_var, is_ptr=is_ptr)))
366
367      if prop.optional:
368        c.Eblock('}')
369
370    if type_.additional_properties is not None:
371      if type_.additional_properties.property_type == PropertyType.ANY:
372        c.Append('value->MergeDictionary(&additional_properties);')
373      else:
374        # Non-copyable types will be wrapped in a linked_ptr for inclusion in
375        # maps, so we need to unwrap them.
376        needs_unwrap = (
377            not self._type_helper.IsCopyable(type_.additional_properties))
378        cpp_type = self._type_helper.GetCppType(type_.additional_properties,
379                                                is_in_container=True)
380        (c.Sblock('for (std::map<std::string, %s>::const_iterator it =' %
381                      cpp_util.PadForGenerics(cpp_type))
382          .Append('       additional_properties.begin();')
383          .Append('   it != additional_properties.end(); ++it) {')
384          .Append('value->SetWithoutPathExpansion(it->first, %s);' %
385              self._CreateValueFromType(
386                  type_.additional_properties,
387                  '%sit->second' % ('*' if needs_unwrap else '')))
388          .Eblock('}')
389        )
390
391    return (c.Append()
392             .Append('return value.Pass();')
393           .Eblock('}'))
394
395  def _GenerateChoiceTypeToValue(self, cpp_namespace, type_):
396    """Generates a function that serializes a choice-representing type
397    into a base::Value.
398    """
399    c = Code()
400    c.Sblock('scoped_ptr<base::Value> %s::ToValue() const {' % cpp_namespace)
401    c.Append('scoped_ptr<base::Value> result;')
402    for choice in type_.choices:
403      choice_var = 'as_%s' % choice.unix_name
404      (c.Sblock('if (%s) {' % choice_var)
405          .Append('DCHECK(!result) << "Cannot set multiple choices for %s";' %
406                      type_.unix_name)
407          .Append('result.reset(%s);' %
408                      self._CreateValueFromType(choice, '*%s' % choice_var))
409        .Eblock('}')
410      )
411    (c.Append('DCHECK(result) << "Must set at least one choice for %s";' %
412                  type_.unix_name)
413      .Append('return result.Pass();')
414      .Eblock('}')
415    )
416    return c
417
418  def _GenerateFunction(self, function):
419    """Generates the definitions for function structs.
420    """
421    c = Code()
422
423    # TODO(kalman): use function.unix_name not Classname.
424    function_namespace = cpp_util.Classname(function.name)
425    # Windows has a #define for SendMessage, so to avoid any issues, we need
426    # to not use the name.
427    if function_namespace == 'SendMessage':
428      function_namespace = 'PassMessage'
429    (c.Append('namespace %s {' % function_namespace)
430      .Append()
431    )
432
433    # Params::Populate function
434    if function.params:
435      c.Concat(self._GeneratePropertyFunctions('Params', function.params))
436      (c.Append('Params::Params() {}')
437        .Append('Params::~Params() {}')
438        .Append()
439        .Cblock(self._GenerateFunctionParamsCreate(function))
440      )
441
442    # Results::Create function
443    if function.callback:
444      c.Concat(self._GenerateCreateCallbackArguments('Results',
445                                                     function.callback))
446
447    c.Append('}  // namespace %s' % function_namespace)
448    return c
449
450  def _GenerateEvent(self, event):
451    # TODO(kalman): use event.unix_name not Classname.
452    c = Code()
453    event_namespace = cpp_util.Classname(event.name)
454    (c.Append('namespace %s {' % event_namespace)
455      .Append()
456      .Cblock(self._GenerateEventNameConstant(None, event))
457      .Cblock(self._GenerateCreateCallbackArguments(None, event))
458      .Append('}  // namespace %s' % event_namespace)
459    )
460    return c
461
462  def _CreateValueFromType(self, type_, var, is_ptr=False):
463    """Creates a base::Value given a type. Generated code passes ownership
464    to caller.
465
466    var: variable or variable*
467
468    E.g for std::string, generate new base::StringValue(var)
469    """
470    underlying_type = self._type_helper.FollowRef(type_)
471    if (underlying_type.property_type == PropertyType.CHOICES or
472        underlying_type.property_type == PropertyType.OBJECT):
473      if is_ptr:
474        return '(%s)->ToValue().release()' % var
475      else:
476        return '(%s).ToValue().release()' % var
477    elif (underlying_type.property_type == PropertyType.ANY or
478          underlying_type.property_type == PropertyType.FUNCTION):
479      if is_ptr:
480        vardot = '(%s)->' % var
481      else:
482        vardot = '(%s).' % var
483      return '%sDeepCopy()' % vardot
484    elif underlying_type.property_type == PropertyType.ENUM:
485      return 'new base::StringValue(ToString(%s))' % var
486    elif underlying_type.property_type == PropertyType.BINARY:
487      if is_ptr:
488        vardot = var + '->'
489      else:
490        vardot = var + '.'
491      return ('base::BinaryValue::CreateWithCopiedBuffer(%sdata(), %ssize())' %
492              (vardot, vardot))
493    elif underlying_type.property_type == PropertyType.ARRAY:
494      return '%s.release()' % self._util_cc_helper.CreateValueFromArray(
495          underlying_type,
496          var,
497          is_ptr)
498    elif underlying_type.property_type.is_fundamental:
499      if is_ptr:
500        var = '*%s' % var
501      if underlying_type.property_type == PropertyType.STRING:
502        return 'new base::StringValue(%s)' % var
503      else:
504        return 'new base::FundamentalValue(%s)' % var
505    else:
506      raise NotImplementedError('Conversion of %s to base::Value not '
507                                'implemented' % repr(type_.type_))
508
509  def _GenerateParamsCheck(self, function, var):
510    """Generates a check for the correct number of arguments when creating
511    Params.
512    """
513    c = Code()
514    num_required = 0
515    for param in function.params:
516      if not param.optional:
517        num_required += 1
518    if num_required == len(function.params):
519      c.Sblock('if (%(var)s.GetSize() != %(total)d) {')
520    elif not num_required:
521      c.Sblock('if (%(var)s.GetSize() > %(total)d) {')
522    else:
523      c.Sblock('if (%(var)s.GetSize() < %(required)d'
524          ' || %(var)s.GetSize() > %(total)d) {')
525    (c.Concat(self._GenerateError(
526        '"expected %%(total)d arguments, got " '
527        '+ base::IntToString(%%(var)s.GetSize())'))
528      .Append('return scoped_ptr<Params>();')
529      .Eblock('}')
530      .Substitute({
531        'var': var,
532        'required': num_required,
533        'total': len(function.params),
534    }))
535    return c
536
537  def _GenerateFunctionParamsCreate(self, function):
538    """Generate function to create an instance of Params. The generated
539    function takes a base::ListValue of arguments.
540
541    E.g for function "Bar", generate Bar::Params::Create()
542    """
543    c = Code()
544    (c.Append('// static')
545      .Sblock('scoped_ptr<Params> Params::Create(%s) {' % self._GenerateParams(
546        ['const base::ListValue& args']))
547      .Concat(self._GenerateParamsCheck(function, 'args'))
548      .Append('scoped_ptr<Params> params(new Params());')
549    )
550
551    for param in function.params:
552      c.Concat(self._InitializePropertyToDefault(param, 'params'))
553
554    for i, param in enumerate(function.params):
555      # Any failure will cause this function to return. If any argument is
556      # incorrect or missing, those following it are not processed. Note that
557      # for optional arguments, we allow missing arguments and proceed because
558      # there may be other arguments following it.
559      failure_value = 'scoped_ptr<Params>()'
560      c.Append()
561      value_var = param.unix_name + '_value'
562      (c.Append('const base::Value* %(value_var)s = NULL;')
563        .Append('if (args.Get(%(i)s, &%(value_var)s) &&')
564        .Sblock('    !%(value_var)s->IsType(base::Value::TYPE_NULL)) {')
565        .Concat(self._GeneratePopulatePropertyFromValue(
566            param, value_var, 'params', failure_value))
567        .Eblock('}')
568      )
569      if not param.optional:
570        (c.Sblock('else {')
571          .Concat(self._GenerateError('"\'%%(key)s\' is required"'))
572          .Append('return %s;' % failure_value)
573          .Eblock('}'))
574      c.Substitute({'value_var': value_var, 'i': i, 'key': param.name})
575    (c.Append()
576      .Append('return params.Pass();')
577      .Eblock('}')
578      .Append()
579    )
580
581    return c
582
583  def _GeneratePopulatePropertyFromValue(self,
584                                         prop,
585                                         src_var,
586                                         dst_class_var,
587                                         failure_value):
588    """Generates code to populate property |prop| of |dst_class_var| (a
589    pointer) from a Value*. See |_GeneratePopulateVariableFromValue| for
590    semantics.
591    """
592    return self._GeneratePopulateVariableFromValue(prop.type_,
593                                                   src_var,
594                                                   '%s->%s' % (dst_class_var,
595                                                               prop.unix_name),
596                                                   failure_value,
597                                                   is_ptr=prop.optional)
598
599  def _GeneratePopulateVariableFromValue(self,
600                                         type_,
601                                         src_var,
602                                         dst_var,
603                                         failure_value,
604                                         is_ptr=False):
605    """Generates code to populate a variable |dst_var| of type |type_| from a
606    Value* at |src_var|. The Value* is assumed to be non-NULL. In the generated
607    code, if |dst_var| fails to be populated then Populate will return
608    |failure_value|.
609    """
610    c = Code()
611
612    underlying_type = self._type_helper.FollowRef(type_)
613
614    if underlying_type.property_type.is_fundamental:
615      if is_ptr:
616        (c.Append('%(cpp_type)s temp;')
617          .Sblock('if (!%s) {' % cpp_util.GetAsFundamentalValue(
618                      self._type_helper.FollowRef(type_), src_var, '&temp'))
619          .Concat(self._GenerateError(
620            '"\'%%(key)s\': expected ' + '%s, got " + %s' % (
621                type_.name,
622                self._util_cc_helper.GetValueTypeString(
623                    '%%(src_var)s', True)))))
624        c.Append('%(dst_var)s.reset();')
625        if not self._generate_error_messages:
626          c.Append('return %(failure_value)s;')
627        (c.Eblock('}')
628          .Append('else')
629          .Append('  %(dst_var)s.reset(new %(cpp_type)s(temp));')
630        )
631      else:
632        (c.Sblock('if (!%s) {' % cpp_util.GetAsFundamentalValue(
633                      self._type_helper.FollowRef(type_),
634                      src_var,
635                      '&%s' % dst_var))
636          .Concat(self._GenerateError(
637            '"\'%%(key)s\': expected ' + '%s, got " + %s' % (
638                type_.name,
639                self._util_cc_helper.GetValueTypeString(
640                    '%%(src_var)s', True))))
641          .Append('return %(failure_value)s;')
642          .Eblock('}')
643        )
644    elif underlying_type.property_type == PropertyType.OBJECT:
645      if is_ptr:
646        (c.Append('const base::DictionaryValue* dictionary = NULL;')
647          .Sblock('if (!%(src_var)s->GetAsDictionary(&dictionary)) {')
648          .Concat(self._GenerateError(
649            '"\'%%(key)s\': expected dictionary, got " + ' +
650            self._util_cc_helper.GetValueTypeString('%%(src_var)s', True))))
651        # If an optional property fails to populate, the population can still
652        # succeed with a warning. If no error messages are generated, this
653        # warning is not set and we fail out instead.
654        if not self._generate_error_messages:
655          c.Append('return %(failure_value)s;')
656        (c.Eblock('}')
657          .Sblock('else {')
658          .Append('scoped_ptr<%(cpp_type)s> temp(new %(cpp_type)s());')
659          .Append('if (!%%(cpp_type)s::Populate(%s)) {' % self._GenerateArgs(
660            ('*dictionary', 'temp.get()')))
661          .Append('  return %(failure_value)s;')
662        )
663        (c.Append('}')
664          .Append('else')
665          .Append('  %(dst_var)s = temp.Pass();')
666          .Eblock('}')
667        )
668      else:
669        (c.Append('const base::DictionaryValue* dictionary = NULL;')
670          .Sblock('if (!%(src_var)s->GetAsDictionary(&dictionary)) {')
671          .Concat(self._GenerateError(
672            '"\'%%(key)s\': expected dictionary, got " + ' +
673            self._util_cc_helper.GetValueTypeString('%%(src_var)s', True)))
674          .Append('return %(failure_value)s;')
675          .Eblock('}')
676          .Append('if (!%%(cpp_type)s::Populate(%s)) {' % self._GenerateArgs(
677            ('*dictionary', '&%(dst_var)s')))
678          .Append('  return %(failure_value)s;')
679          .Append('}')
680        )
681    elif underlying_type.property_type == PropertyType.FUNCTION:
682      if is_ptr:
683        c.Append('%(dst_var)s.reset(new base::DictionaryValue());')
684    elif underlying_type.property_type == PropertyType.ANY:
685      c.Append('%(dst_var)s.reset(%(src_var)s->DeepCopy());')
686    elif underlying_type.property_type == PropertyType.ARRAY:
687      # util_cc_helper deals with optional and required arrays
688      (c.Append('const base::ListValue* list = NULL;')
689        .Sblock('if (!%(src_var)s->GetAsList(&list)) {')
690          .Concat(self._GenerateError(
691            '"\'%%(key)s\': expected list, got " + ' +
692            self._util_cc_helper.GetValueTypeString('%%(src_var)s', True)))
693      )
694      if is_ptr and self._generate_error_messages:
695        c.Append('%(dst_var)s.reset();')
696      else:
697        c.Append('return %(failure_value)s;')
698      c.Eblock('}')
699      c.Sblock('else {')
700      item_type = self._type_helper.FollowRef(underlying_type.item_type)
701      if item_type.property_type == PropertyType.ENUM:
702        c.Concat(self._GenerateListValueToEnumArrayConversion(
703                     item_type,
704                     'list',
705                     dst_var,
706                     failure_value,
707                     is_ptr=is_ptr))
708      else:
709        (c.Sblock('if (!%s) {' % self._util_cc_helper.PopulateArrayFromList(
710              underlying_type,
711              'list',
712              dst_var,
713              is_ptr)))
714        c.Concat(self._GenerateError(
715            '"unable to populate array \'%%(parent_key)s\'"'))
716        if is_ptr and self._generate_error_messages:
717          c.Append('%(dst_var)s.reset();')
718        else:
719          c.Append('return %(failure_value)s;')
720        c.Eblock('}')
721      c.Eblock('}')
722    elif underlying_type.property_type == PropertyType.CHOICES:
723      if is_ptr:
724        (c.Append('scoped_ptr<%(cpp_type)s> temp(new %(cpp_type)s());')
725          .Append('if (!%%(cpp_type)s::Populate(%s))' % self._GenerateArgs(
726            ('*%(src_var)s', 'temp.get()')))
727          .Append('  return %(failure_value)s;')
728          .Append('%(dst_var)s = temp.Pass();')
729        )
730      else:
731        (c.Append('if (!%%(cpp_type)s::Populate(%s))' % self._GenerateArgs(
732            ('*%(src_var)s', '&%(dst_var)s')))
733          .Append('  return %(failure_value)s;'))
734    elif underlying_type.property_type == PropertyType.ENUM:
735      c.Concat(self._GenerateStringToEnumConversion(underlying_type,
736                                                    src_var,
737                                                    dst_var,
738                                                    failure_value))
739    elif underlying_type.property_type == PropertyType.BINARY:
740      (c.Append('const base::BinaryValue* binary_value = NULL;')
741        .Sblock('if (!%(src_var)s->IsType(base::Value::TYPE_BINARY)) {')
742        .Concat(self._GenerateError(
743          '"\'%%(key)s\': expected binary, got " + ' +
744          self._util_cc_helper.GetValueTypeString('%%(src_var)s', True)))
745      )
746      if not self._generate_error_messages:
747        c.Append('return %(failure_value)s;')
748      (c.Eblock('}')
749        .Sblock('else {')
750        .Append(' binary_value =')
751        .Append('   static_cast<const base::BinaryValue*>(%(src_var)s);')
752      )
753      if is_ptr:
754        (c.Append('%(dst_var)s.reset(')
755          .Append('    new std::string(binary_value->GetBuffer(),')
756          .Append('                    binary_value->GetSize()));')
757        )
758      else:
759        (c.Append('%(dst_var)s.assign(binary_value->GetBuffer(),')
760          .Append('                   binary_value->GetSize());')
761        )
762      c.Eblock('}')
763    else:
764      raise NotImplementedError(type_)
765    if c.IsEmpty():
766      return c
767    return Code().Sblock('{').Concat(c.Substitute({
768      'cpp_type': self._type_helper.GetCppType(type_),
769      'src_var': src_var,
770      'dst_var': dst_var,
771      'failure_value': failure_value,
772      'key': type_.name,
773      'parent_key': type_.parent.name,
774    })).Eblock('}')
775
776  def _GenerateListValueToEnumArrayConversion(self,
777                                              item_type,
778                                              src_var,
779                                              dst_var,
780                                              failure_value,
781                                              is_ptr=False):
782    """Returns Code that converts a ListValue of string constants from
783    |src_var| into an array of enums of |type_| in |dst_var|. On failure,
784    returns |failure_value|.
785    """
786    c = Code()
787    accessor = '.'
788    if is_ptr:
789      accessor = '->'
790      cpp_type = self._type_helper.GetCppType(item_type, is_in_container=True)
791      c.Append('%s.reset(new std::vector<%s>);' %
792                   (dst_var, cpp_util.PadForGenerics(cpp_type)))
793    (c.Sblock('for (base::ListValue::const_iterator it = %s->begin(); '
794                   'it != %s->end(); ++it) {' % (src_var, src_var))
795      .Append('%s tmp;' % self._type_helper.GetCppType(item_type))
796      .Concat(self._GenerateStringToEnumConversion(item_type,
797                                                   '(*it)',
798                                                   'tmp',
799                                                   failure_value))
800      .Append('%s%spush_back(tmp);' % (dst_var, accessor))
801      .Eblock('}')
802    )
803    return c
804
805  def _GenerateStringToEnumConversion(self,
806                                      type_,
807                                      src_var,
808                                      dst_var,
809                                      failure_value):
810    """Returns Code that converts a string type in |src_var| to an enum with
811    type |type_| in |dst_var|. In the generated code, if |src_var| is not
812    a valid enum name then the function will return |failure_value|.
813    """
814    if type_.property_type != PropertyType.ENUM:
815      raise TypeError(type_)
816    c = Code()
817    enum_as_string = '%s_as_string' % type_.unix_name
818    cpp_type_namespace = ''
819    if type_.namespace != self._namespace:
820      cpp_type_namespace = '%s::' % type_.namespace.unix_name
821    cpp_type_name = self._type_helper.GetCppType(type_)
822    (c.Append('std::string %s;' % enum_as_string)
823      .Sblock('if (!%s->GetAsString(&%s)) {' % (src_var, enum_as_string))
824      .Concat(self._GenerateError(
825        '"\'%%(key)s\': expected string, got " + ' +
826        self._util_cc_helper.GetValueTypeString('%%(src_var)s', True)))
827      .Append('return %s;' % failure_value)
828      .Eblock('}')
829      .Append('%s = %sParse%s(%s);' % (dst_var,
830                                       cpp_type_namespace,
831                                       cpp_util.Classname(type_.name),
832                                       enum_as_string))
833      .Sblock('if (%s == %s%s) {' % (dst_var,
834                                     cpp_type_namespace,
835                                     self._type_helper.GetEnumNoneValue(type_)))
836      .Concat(self._GenerateError(
837        '\"\'%%(key)s\': expected \\"' +
838        '\\" or \\"'.join(
839            enum_value.name
840            for enum_value in self._type_helper.FollowRef(type_).enum_values) +
841        '\\", got \\"" + %s + "\\""' % enum_as_string))
842      .Append('return %s;' % failure_value)
843      .Eblock('}')
844      .Substitute({'src_var': src_var, 'key': type_.name})
845    )
846    return c
847
848  def _GeneratePropertyFunctions(self, namespace, params):
849    """Generates the member functions for a list of parameters.
850    """
851    return self._GenerateTypes(namespace, (param.type_ for param in params))
852
853  def _GenerateTypes(self, namespace, types):
854    """Generates the member functions for a list of types.
855    """
856    c = Code()
857    for type_ in types:
858      c.Cblock(self._GenerateType(namespace, type_))
859    return c
860
861  def _GenerateEnumToString(self, cpp_namespace, type_):
862    """Generates ToString() which gets the string representation of an enum.
863    """
864    c = Code()
865    classname = cpp_util.Classname(schema_util.StripNamespace(type_.name))
866
867    if cpp_namespace is not None:
868      c.Append('// static')
869    maybe_namespace = '' if cpp_namespace is None else '%s::' % cpp_namespace
870
871    c.Sblock('std::string %sToString(%s enum_param) {' %
872                 (maybe_namespace, classname))
873    c.Sblock('switch (enum_param) {')
874    for enum_value in self._type_helper.FollowRef(type_).enum_values:
875      (c.Append('case %s: ' % self._type_helper.GetEnumValue(type_, enum_value))
876        .Append('  return "%s";' % enum_value.name))
877    (c.Append('case %s:' % self._type_helper.GetEnumNoneValue(type_))
878      .Append('  return "";')
879      .Eblock('}')
880      .Append('NOTREACHED();')
881      .Append('return "";')
882      .Eblock('}')
883    )
884    return c
885
886  def _GenerateEnumFromString(self, cpp_namespace, type_):
887    """Generates FromClassNameString() which gets an enum from its string
888    representation.
889    """
890    c = Code()
891    classname = cpp_util.Classname(schema_util.StripNamespace(type_.name))
892
893    if cpp_namespace is not None:
894      c.Append('// static')
895    maybe_namespace = '' if cpp_namespace is None else '%s::' % cpp_namespace
896
897    c.Sblock('%s%s %sParse%s(const std::string& enum_string) {' %
898                 (maybe_namespace, classname, maybe_namespace, classname))
899    for i, enum_value in enumerate(
900          self._type_helper.FollowRef(type_).enum_values):
901      # This is broken up into all ifs with no else ifs because we get
902      # "fatal error C1061: compiler limit : blocks nested too deeply"
903      # on Windows.
904      (c.Append('if (enum_string == "%s")' % enum_value.name)
905        .Append('  return %s;' %
906            self._type_helper.GetEnumValue(type_, enum_value)))
907    (c.Append('return %s;' % self._type_helper.GetEnumNoneValue(type_))
908      .Eblock('}')
909    )
910    return c
911
912  def _GenerateCreateCallbackArguments(self, function_scope, callback):
913    """Generate all functions to create Value parameters for a callback.
914
915    E.g for function "Bar", generate Bar::Results::Create
916    E.g for event "Baz", generate Baz::Create
917
918    function_scope: the function scope path, e.g. Foo::Bar for the function
919                    Foo::Bar::Baz(). May be None if there is no function scope.
920    callback: the Function object we are creating callback arguments for.
921    """
922    c = Code()
923    params = callback.params
924    c.Concat(self._GeneratePropertyFunctions(function_scope, params))
925
926    (c.Sblock('scoped_ptr<base::ListValue> %(function_scope)s'
927                  'Create(%(declaration_list)s) {')
928      .Append('scoped_ptr<base::ListValue> create_results('
929              'new base::ListValue());')
930    )
931    declaration_list = []
932    for param in params:
933      declaration_list.append(cpp_util.GetParameterDeclaration(
934          param, self._type_helper.GetCppType(param.type_)))
935      c.Append('create_results->Append(%s);' %
936          self._CreateValueFromType(param.type_, param.unix_name))
937    c.Append('return create_results.Pass();')
938    c.Eblock('}')
939    c.Substitute({
940        'function_scope': ('%s::' % function_scope) if function_scope else '',
941        'declaration_list': ', '.join(declaration_list),
942        'param_names': ', '.join(param.unix_name for param in params)
943    })
944    return c
945
946  def _GenerateEventNameConstant(self, function_scope, event):
947    """Generates a constant string array for the event name.
948    """
949    c = Code()
950    c.Append('const char kEventName[] = "%s.%s";' % (
951                 self._namespace.name, event.name))
952    return c
953
954  def _InitializePropertyToDefault(self, prop, dst):
955    """Initialize a model.Property to its default value inside an object.
956
957    E.g for optional enum "state", generate dst->state = STATE_NONE;
958
959    dst: Type*
960    """
961    c = Code()
962    underlying_type = self._type_helper.FollowRef(prop.type_)
963    if (underlying_type.property_type == PropertyType.ENUM and
964        prop.optional):
965      c.Append('%s->%s = %s;' % (
966        dst,
967        prop.unix_name,
968        self._type_helper.GetEnumNoneValue(prop.type_)))
969    return c
970
971  def _GenerateError(self, body):
972    """Generates an error message pertaining to population failure.
973
974    E.g 'expected bool, got int'
975    """
976    c = Code()
977    if not self._generate_error_messages:
978      return c
979    (c.Append('if (error) {')
980      .Append('  if (error->length())')
981      .Append('    error->append(UTF8ToUTF16("; "));')
982      .Append('  error->append(UTF8ToUTF16(%s));' % body)
983      .Append('}')
984      .Append('else')
985      .Append('  *error = UTF8ToUTF16(%s);' % body))
986    return c
987
988  def _GenerateParams(self, params):
989    """Builds the parameter list for a function, given an array of parameters.
990    """
991    if self._generate_error_messages:
992      params = list(params) + ['base::string16* error']
993    return ', '.join(str(p) for p in params)
994
995  def _GenerateArgs(self, args):
996    """Builds the argument list for a function, given an array of arguments.
997    """
998    if self._generate_error_messages:
999      args = list(args) + ['error']
1000    return ', '.join(str(a) for a in args)
1001