1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc.  All rights reserved.
3// http://code.google.com/p/protobuf/
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions are
7// met:
8//
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10// notice, this list of conditions and the following disclaimer.
11//     * Redistributions in binary form must reproduce the above
12// copyright notice, this list of conditions and the following disclaimer
13// in the documentation and/or other materials provided with the
14// distribution.
15//     * Neither the name of Google Inc. nor the names of its
16// contributors may be used to endorse or promote products derived from
17// this software without specific prior written permission.
18//
19// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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29// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31// Author: kenton@google.com (Kenton Varda)
32//  Based on original Protocol Buffers design by
33//  Sanjay Ghemawat, Jeff Dean, and others.
34
35#ifndef GOOGLE_PROTOBUF_COMPILER_CPP_FIELD_H__
36#define GOOGLE_PROTOBUF_COMPILER_CPP_FIELD_H__
37
38#include <map>
39#include <string>
40
41#include <google/protobuf/stubs/common.h>
42#include <google/protobuf/descriptor.h>
43#include <google/protobuf/compiler/cpp/cpp_options.h>
44
45namespace google {
46namespace protobuf {
47  namespace io {
48    class Printer;             // printer.h
49  }
50}
51
52namespace protobuf {
53namespace compiler {
54namespace cpp {
55
56// Helper function: set variables in the map that are the same for all
57// field code generators.
58// ['name', 'index', 'number', 'classname', 'declared_type', 'tag_size',
59// 'deprecation'].
60void SetCommonFieldVariables(const FieldDescriptor* descriptor,
61                             map<string, string>* variables,
62                             const Options& options);
63
64class FieldGenerator {
65 public:
66  FieldGenerator() {}
67  virtual ~FieldGenerator();
68
69  // Generate lines of code declaring members fields of the message class
70  // needed to represent this field.  These are placed inside the message
71  // class.
72  virtual void GeneratePrivateMembers(io::Printer* printer) const = 0;
73
74  // Generate prototypes for all of the accessor functions related to this
75  // field.  These are placed inside the class definition.
76  virtual void GenerateAccessorDeclarations(io::Printer* printer) const = 0;
77
78  // Generate inline definitions of accessor functions for this field.
79  // These are placed inside the header after all class definitions.
80  virtual void GenerateInlineAccessorDefinitions(
81    io::Printer* printer) const = 0;
82
83  // Generate definitions of accessors that aren't inlined.  These are
84  // placed somewhere in the .cc file.
85  // Most field types don't need this, so the default implementation is empty.
86  virtual void GenerateNonInlineAccessorDefinitions(
87    io::Printer* printer) const {}
88
89  // Generate lines of code (statements, not declarations) which clear the
90  // field.  This is used to define the clear_$name$() method as well as
91  // the Clear() method for the whole message.
92  virtual void GenerateClearingCode(io::Printer* printer) const = 0;
93
94  // Generate lines of code (statements, not declarations) which merges the
95  // contents of the field from the current message to the target message,
96  // which is stored in the generated code variable "from".
97  // This is used to fill in the MergeFrom method for the whole message.
98  // Details of this usage can be found in message.cc under the
99  // GenerateMergeFrom method.
100  virtual void GenerateMergingCode(io::Printer* printer) const = 0;
101
102  // Generate lines of code (statements, not declarations) which swaps
103  // this field and the corresponding field of another message, which
104  // is stored in the generated code variable "other". This is used to
105  // define the Swap method. Details of usage can be found in
106  // message.cc under the GenerateSwap method.
107  virtual void GenerateSwappingCode(io::Printer* printer) const = 0;
108
109  // Generate initialization code for private members declared by
110  // GeneratePrivateMembers(). These go into the message class's SharedCtor()
111  // method, invoked by each of the generated constructors.
112  virtual void GenerateConstructorCode(io::Printer* printer) const = 0;
113
114  // Generate any code that needs to go in the class's SharedDtor() method,
115  // invoked by the destructor.
116  // Most field types don't need this, so the default implementation is empty.
117  virtual void GenerateDestructorCode(io::Printer* printer) const {}
118
119  // Generate code that allocates the fields's default instance.
120  virtual void GenerateDefaultInstanceAllocator(io::Printer* printer) const {}
121
122  // Generate code that should be run when ShutdownProtobufLibrary() is called,
123  // to delete all dynamically-allocated objects.
124  virtual void GenerateShutdownCode(io::Printer* printer) const {}
125
126  // Generate lines to decode this field, which will be placed inside the
127  // message's MergeFromCodedStream() method.
128  virtual void GenerateMergeFromCodedStream(io::Printer* printer) const = 0;
129
130  // Generate lines to decode this field from a packed value, which will be
131  // placed inside the message's MergeFromCodedStream() method.
132  virtual void GenerateMergeFromCodedStreamWithPacking(io::Printer* printer)
133      const;
134
135  // Generate lines to serialize this field, which are placed within the
136  // message's SerializeWithCachedSizes() method.
137  virtual void GenerateSerializeWithCachedSizes(io::Printer* printer) const = 0;
138
139  // Generate lines to serialize this field directly to the array "target",
140  // which are placed within the message's SerializeWithCachedSizesToArray()
141  // method. This must also advance "target" past the written bytes.
142  virtual void GenerateSerializeWithCachedSizesToArray(
143      io::Printer* printer) const = 0;
144
145  // Generate lines to compute the serialized size of this field, which
146  // are placed in the message's ByteSize() method.
147  virtual void GenerateByteSize(io::Printer* printer) const = 0;
148
149 private:
150  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGenerator);
151};
152
153// Convenience class which constructs FieldGenerators for a Descriptor.
154class FieldGeneratorMap {
155 public:
156  explicit FieldGeneratorMap(const Descriptor* descriptor, const Options& options);
157  ~FieldGeneratorMap();
158
159  const FieldGenerator& get(const FieldDescriptor* field) const;
160
161 private:
162  const Descriptor* descriptor_;
163  scoped_array<scoped_ptr<FieldGenerator> > field_generators_;
164
165  static FieldGenerator* MakeGenerator(const FieldDescriptor* field,
166                                       const Options& options);
167
168  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGeneratorMap);
169};
170
171
172}  // namespace cpp
173}  // namespace compiler
174}  // namespace protobuf
175
176}  // namespace google
177#endif  // GOOGLE_PROTOBUF_COMPILER_CPP_FIELD_H__
178