2 * Copyright 2014 Google Inc. All rights reserved.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #ifndef FLATBUFFERS_CODE_GENERATORS_H_
18 #define FLATBUFFERS_CODE_GENERATORS_H_
23 #include "flatbuffers/idl.h"
25 namespace flatbuffers {
27 // Utility class to assist in generating code through use of text templates.
30 // CodeWriter code("\t");
31 // code.SetValue("NAME", "Foo");
32 // code += "void {{NAME}}() { printf("%s", "{{NAME}}"); }";
33 // code.SetValue("NAME", "Bar");
34 // code += "void {{NAME}}() { printf("%s", "{{NAME}}"); }";
35 // std::cout << code.ToString() << std::endl;
38 // void Foo() { printf("%s", "Foo"); }
39 // void Bar() { printf("%s", "Bar"); }
42 CodeWriter(std::string pad = std::string())
43 : pad_(pad), cur_ident_lvl_(0), ignore_ident_(false) {}
45 // Clears the current "written" code.
51 // Associates a key with a value. All subsequent calls to operator+=, where
52 // the specified key is contained in {{ and }} delimiters will be replaced by
54 void SetValue(const std::string &key, const std::string &value) {
55 value_map_[key] = value;
58 std::string GetValue(const std::string &key) const {
59 const auto it = value_map_.find(key);
60 return it == value_map_.end() ? "" : it->second;
63 // Appends the given text to the generated code as well as a newline
64 // character. Any text within {{ and }} delimeters is replaced by values
65 // previously stored in the CodeWriter by calling SetValue above. The newline
66 // will be suppressed if the text ends with the \\ character.
67 void operator+=(std::string text);
69 // Returns the current contents of the CodeWriter as a std::string.
70 std::string ToString() const { return stream_.str(); }
72 // Increase ident level for writing code
73 void IncrementIdentLevel() { cur_ident_lvl_++; }
74 // Decrease ident level for writing code
75 void DecrementIdentLevel() {
76 if (cur_ident_lvl_) cur_ident_lvl_--;
80 std::map<std::string, std::string> value_map_;
81 std::stringstream stream_;
86 // Add ident padding (tab or space) based on ident level
87 void AppendIdent(std::stringstream &stream);
92 virtual bool generate() = 0;
94 static std::string NamespaceDir(const Parser &parser, const std::string &path,
98 BaseGenerator(const Parser &parser, const std::string &path,
99 const std::string &file_name, std::string qualifying_start,
100 std::string qualifying_separator)
103 file_name_(file_name),
104 qualifying_start_(qualifying_start),
105 qualifying_separator_(qualifying_separator) {}
106 virtual ~BaseGenerator() {}
109 BaseGenerator &operator=(const BaseGenerator &);
110 BaseGenerator(const BaseGenerator &);
112 std::string NamespaceDir(const Namespace &ns) const;
114 static const char *FlatBuffersGeneratedWarning();
116 static std::string FullNamespace(const char *separator, const Namespace &ns);
118 static std::string LastNamespacePart(const Namespace &ns);
120 // tracks the current namespace for early exit in WrapInNameSpace
121 // c++, java and csharp returns a different namespace from
122 // the following default (no early exit, always fully qualify),
123 // which works for js and php
124 virtual const Namespace *CurrentNameSpace() const { return nullptr; }
126 // Ensure that a type is prefixed with its namespace even within
127 // its own namespace to avoid conflict between generated method
128 // names and similarly named classes or structs
129 std::string WrapInNameSpace(const Namespace *ns,
130 const std::string &name) const;
132 std::string WrapInNameSpace(const Definition &def) const;
134 std::string GetNameSpace(const Definition &def) const;
136 const Parser &parser_;
137 const std::string &path_;
138 const std::string &file_name_;
139 const std::string qualifying_start_;
140 const std::string qualifying_separator_;
143 struct CommentConfig {
144 const char *first_line;
145 const char *content_line_prefix;
146 const char *last_line;
149 extern void GenComment(const std::vector<std::string> &dc,
150 std::string *code_ptr, const CommentConfig *config,
151 const char *prefix = "");
153 class FloatConstantGenerator {
155 virtual ~FloatConstantGenerator() {}
156 std::string GenFloatConstant(const FieldDef &field) const;
159 virtual std::string Value(double v, const std::string &src) const = 0;
160 virtual std::string Inf(double v) const = 0;
161 virtual std::string NaN(double v) const = 0;
163 virtual std::string Value(float v, const std::string &src) const = 0;
164 virtual std::string Inf(float v) const = 0;
165 virtual std::string NaN(float v) const = 0;
168 std::string GenFloatConstantImpl(const FieldDef &field) const;
171 class SimpleFloatConstantGenerator : public FloatConstantGenerator {
173 SimpleFloatConstantGenerator(const char *nan_number,
174 const char *pos_inf_number,
175 const char *neg_inf_number);
178 std::string Value(double v,
179 const std::string &src) const FLATBUFFERS_OVERRIDE;
180 std::string Inf(double v) const FLATBUFFERS_OVERRIDE;
181 std::string NaN(double v) const FLATBUFFERS_OVERRIDE;
183 std::string Value(float v, const std::string &src) const FLATBUFFERS_OVERRIDE;
184 std::string Inf(float v) const FLATBUFFERS_OVERRIDE;
185 std::string NaN(float v) const FLATBUFFERS_OVERRIDE;
187 const std::string nan_number_;
188 const std::string pos_inf_number_;
189 const std::string neg_inf_number_;
192 // C++, C#, Java like generator.
193 class TypedFloatConstantGenerator : public FloatConstantGenerator {
195 TypedFloatConstantGenerator(const char *double_prefix,
196 const char *single_prefix, const char *nan_number,
197 const char *pos_inf_number,
198 const char *neg_inf_number = "");
201 std::string Value(double v,
202 const std::string &src) const FLATBUFFERS_OVERRIDE;
203 std::string Inf(double v) const FLATBUFFERS_OVERRIDE;
205 std::string NaN(double v) const FLATBUFFERS_OVERRIDE;
207 std::string Value(float v, const std::string &src) const FLATBUFFERS_OVERRIDE;
208 std::string Inf(float v) const FLATBUFFERS_OVERRIDE;
209 std::string NaN(float v) const FLATBUFFERS_OVERRIDE;
211 std::string MakeNaN(const std::string &prefix) const;
212 std::string MakeInf(bool neg, const std::string &prefix) const;
214 const std::string double_prefix_;
215 const std::string single_prefix_;
216 const std::string nan_number_;
217 const std::string pos_inf_number_;
218 const std::string neg_inf_number_;
221 } // namespace flatbuffers
223 #endif // FLATBUFFERS_CODE_GENERATORS_H_