1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc.  All rights reserved.
3// http://code.google.com/p/protobuf/
4//
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18//
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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
44namespace google {
45namespace protobuf {
46  namespace io {
47    class Printer;             // printer.h
48  }
49}
50
51namespace protobuf {
52namespace compiler {
53namespace cpp {
54
55// Helper function: set variables in the map that are the same for all
56// field code generators.
57// ['name', 'index', 'number', 'classname', 'declared_type', 'tag_size',
58// 'deprecation'].
59void SetCommonFieldVariables(const FieldDescriptor* descriptor,
60                             map<string, string>* variables);
61
62class FieldGenerator {
63 public:
64  FieldGenerator() {}
65  virtual ~FieldGenerator();
66
67  // Generate lines of code declaring members fields of the message class
68  // needed to represent this field.  These are placed inside the message
69  // class.
70  virtual void GeneratePrivateMembers(io::Printer* printer) const = 0;
71
72  // Generate prototypes for all of the accessor functions related to this
73  // field.  These are placed inside the class definition.
74  virtual void GenerateAccessorDeclarations(io::Printer* printer) const = 0;
75
76  // Generate inline definitions of accessor functions for this field.
77  // These are placed inside the header after all class definitions.
78  virtual void GenerateInlineAccessorDefinitions(
79    io::Printer* printer) const = 0;
80
81  // Generate definitions of accessors that aren't inlined.  These are
82  // placed somewhere in the .cc file.
83  // Most field types don't need this, so the default implementation is empty.
84  virtual void GenerateNonInlineAccessorDefinitions(
85    io::Printer* printer) const {}
86
87  // Generate lines of code (statements, not declarations) which clear the
88  // field.  This is used to define the clear_$name$() method as well as
89  // the Clear() method for the whole message.
90  virtual void GenerateClearingCode(io::Printer* printer) const = 0;
91
92  // Generate lines of code (statements, not declarations) which merges the
93  // contents of the field from the current message to the target message,
94  // which is stored in the generated code variable "from".
95  // This is used to fill in the MergeFrom method for the whole message.
96  // Details of this usage can be found in message.cc under the
97  // GenerateMergeFrom method.
98  virtual void GenerateMergingCode(io::Printer* printer) const = 0;
99
100  // Generate lines of code (statements, not declarations) which swaps
101  // this field and the corresponding field of another message, which
102  // is stored in the generated code variable "other". This is used to
103  // define the Swap method. Details of usage can be found in
104  // message.cc under the GenerateSwap method.
105  virtual void GenerateSwappingCode(io::Printer* printer) const = 0;
106
107  // Generate initialization code for private members declared by
108  // GeneratePrivateMembers(). These go into the message class's SharedCtor()
109  // method, invoked by each of the generated constructors.
110  virtual void GenerateConstructorCode(io::Printer* printer) const = 0;
111
112  // Generate any code that needs to go in the class's SharedDtor() method,
113  // invoked by the destructor.
114  // Most field types don't need this, so the default implementation is empty.
115  virtual void GenerateDestructorCode(io::Printer* printer) const {}
116
117  // Generate lines to decode this field, which will be placed inside the
118  // message's MergeFromCodedStream() method.
119  virtual void GenerateMergeFromCodedStream(io::Printer* printer) const = 0;
120
121  // Generate lines to decode this field from a packed value, which will be
122  // placed inside the message's MergeFromCodedStream() method.
123  virtual void GenerateMergeFromCodedStreamWithPacking(io::Printer* printer)
124      const;
125
126  // Generate lines to serialize this field, which are placed within the
127  // message's SerializeWithCachedSizes() method.
128  virtual void GenerateSerializeWithCachedSizes(io::Printer* printer) const = 0;
129
130  // Generate lines to serialize this field directly to the array "target",
131  // which are placed within the message's SerializeWithCachedSizesToArray()
132  // method. This must also advance "target" past the written bytes.
133  virtual void GenerateSerializeWithCachedSizesToArray(
134      io::Printer* printer) const = 0;
135
136  // Generate lines to compute the serialized size of this field, which
137  // are placed in the message's ByteSize() method.
138  virtual void GenerateByteSize(io::Printer* printer) const = 0;
139
140 private:
141  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGenerator);
142};
143
144// Convenience class which constructs FieldGenerators for a Descriptor.
145class FieldGeneratorMap {
146 public:
147  explicit FieldGeneratorMap(const Descriptor* descriptor);
148  ~FieldGeneratorMap();
149
150  const FieldGenerator& get(const FieldDescriptor* field) const;
151
152 private:
153  const Descriptor* descriptor_;
154  scoped_array<scoped_ptr<FieldGenerator> > field_generators_;
155
156  static FieldGenerator* MakeGenerator(const FieldDescriptor* field);
157
158  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FieldGeneratorMap);
159};
160
161
162}  // namespace cpp
163}  // namespace compiler
164}  // namespace protobuf
165
166}  // namespace google
167#endif  // GOOGLE_PROTOBUF_COMPILER_CPP_FIELD_H__
168