1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc.  All rights reserved.
3// https://developers.google.com/protocol-buffers/
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//
9//     * Redistributions of source code must retain the above copyright
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
23// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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 <memory>
40#include <string>
41
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
64void SetCommonOneofFieldVariables(const FieldDescriptor* descriptor,
65                                  map<string, string>* variables);
66
67class FieldGenerator {
68 public:
69  FieldGenerator() {}
70  virtual ~FieldGenerator();
71
72  // Generate lines of code declaring members fields of the message class
73  // needed to represent this field.  These are placed inside the message
74  // class.
75  virtual void GeneratePrivateMembers(io::Printer* printer) const = 0;
76
77  // Generate static default variable for this field. These are placed inside
78  // the message class. Most field types don't need this, so the default
79  // implementation is empty.
80  virtual void GenerateStaticMembers(io::Printer* printer) const {}
81
82  // Generate prototypes for all of the accessor functions related to this
83  // field.  These are placed inside the class definition.
84  virtual void GenerateAccessorDeclarations(io::Printer* printer) const = 0;
85
86  // Generate inline definitions of accessor functions for this field.
87  // These are placed inside the header after all class definitions.
88  virtual void GenerateInlineAccessorDefinitions(
89    io::Printer* printer) const = 0;
90
91  // Generate definitions of accessors that aren't inlined.  These are
92  // placed somewhere in the .cc file.
93  // Most field types don't need this, so the default implementation is empty.
94  virtual void GenerateNonInlineAccessorDefinitions(
95    io::Printer* printer) const {}
96
97  // Generate lines of code (statements, not declarations) which clear the
98  // field.  This is used to define the clear_$name$() method as well as
99  // the Clear() method for the whole message.
100  virtual void GenerateClearingCode(io::Printer* printer) const = 0;
101
102  // Generate lines of code (statements, not declarations) which merges the
103  // contents of the field from the current message to the target message,
104  // which is stored in the generated code variable "from".
105  // This is used to fill in the MergeFrom method for the whole message.
106  // Details of this usage can be found in message.cc under the
107  // GenerateMergeFrom method.
108  virtual void GenerateMergingCode(io::Printer* printer) const = 0;
109
110  // Generate lines of code (statements, not declarations) which swaps
111  // this field and the corresponding field of another message, which
112  // is stored in the generated code variable "other". This is used to
113  // define the Swap method. Details of usage can be found in
114  // message.cc under the GenerateSwap method.
115  virtual void GenerateSwappingCode(io::Printer* printer) const = 0;
116
117  // Generate initialization code for private members declared by
118  // GeneratePrivateMembers(). These go into the message class's SharedCtor()
119  // method, invoked by each of the generated constructors.
120  virtual void GenerateConstructorCode(io::Printer* printer) const = 0;
121
122  // Generate any code that needs to go in the class's SharedDtor() method,
123  // invoked by the destructor.
124  // Most field types don't need this, so the default implementation is empty.
125  virtual void GenerateDestructorCode(io::Printer* printer) const {}
126
127  // Generate code that allocates the fields's default instance.
128  virtual void GenerateDefaultInstanceAllocator(io::Printer* printer) const {}
129
130  // Generate code that should be run when ShutdownProtobufLibrary() is called,
131  // to delete all dynamically-allocated objects.
132  virtual void GenerateShutdownCode(io::Printer* printer) const {}
133
134  // Generate lines to decode this field, which will be placed inside the
135  // message's MergeFromCodedStream() method.
136  virtual void GenerateMergeFromCodedStream(io::Printer* printer) const = 0;
137
138  // Generate lines to decode this field from a packed value, which will be
139  // placed inside the message's MergeFromCodedStream() method.
140  virtual void GenerateMergeFromCodedStreamWithPacking(io::Printer* printer)
141      const;
142
143  // Generate lines to serialize this field, which are placed within the
144  // message's SerializeWithCachedSizes() method.
145  virtual void GenerateSerializeWithCachedSizes(io::Printer* printer) const = 0;
146
147  // Generate lines to serialize this field directly to the array "target",
148  // which are placed within the message's SerializeWithCachedSizesToArray()
149  // method. This must also advance "target" past the written bytes.
150  virtual void GenerateSerializeWithCachedSizesToArray(
151      io::Printer* printer) const = 0;
152
153  // Generate lines to compute the serialized size of this field, which
154  // are placed in the message's ByteSize() method.
155  virtual void GenerateByteSize(io::Printer* printer) const = 0;
156
157 private:
158  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGenerator);
159};
160
161// Convenience class which constructs FieldGenerators for a Descriptor.
162class FieldGeneratorMap {
163 public:
164  explicit FieldGeneratorMap(const Descriptor* descriptor, const Options& options);
165  ~FieldGeneratorMap();
166
167  const FieldGenerator& get(const FieldDescriptor* field) const;
168
169 private:
170  const Descriptor* descriptor_;
171  scoped_array<scoped_ptr<FieldGenerator> > field_generators_;
172
173  static FieldGenerator* MakeGenerator(const FieldDescriptor* field,
174                                       const Options& options);
175
176  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGeneratorMap);
177};
178
179
180}  // namespace cpp
181}  // namespace compiler
182}  // namespace protobuf
183
184}  // namespace google
185#endif  // GOOGLE_PROTOBUF_COMPILER_CPP_FIELD_H__
186