| // Protocol Buffers - Google's data interchange format |
| // Copyright 2008 Google Inc. |
| // http://code.google.com/p/protobuf/ |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Author: kenton@google.com (Kenton Varda) |
| // Based on original Protocol Buffers design by |
| // Sanjay Ghemawat, Jeff Dean, and others. |
| // |
| // Utility class for writing text to a ZeroCopyOutputStream. |
| |
| #ifndef GOOGLE_PROTOBUF_IO_PRINTER_H__ |
| #define GOOGLE_PROTOBUF_IO_PRINTER_H__ |
| |
| #include <string> |
| #include <map> |
| #include <google/protobuf/stubs/common.h> |
| |
| namespace google { |
| namespace protobuf { |
| namespace io { |
| |
| class ZeroCopyOutputStream; // zero_copy_stream.h |
| |
| // This simple utility class assists in code generation. It basically |
| // allows the caller to define a set of variables and then output some |
| // text with variable substitutions. Example usage: |
| // |
| // Printer printer(output, '$'); |
| // map<string, string> vars; |
| // vars["name"] = "Bob"; |
| // printer.Print(vars, "My name is $name$."); |
| // |
| // The above writes "My name is Bob." to the output stream. |
| // |
| // Printer aggressively enforces correct usage, crashing (with assert failures) |
| // in the case of undefined variables. This helps greatly in debugging code |
| // which uses it. This class is not intended to be used by production servers. |
| class LIBPROTOBUF_EXPORT Printer { |
| public: |
| // Create a printer that writes text to the given output stream. Use the |
| // given character as the delimiter for variables. |
| Printer(ZeroCopyOutputStream* output, char variable_delimiter); |
| ~Printer(); |
| |
| // Print some text after applying variable substitutions. If a particular |
| // variable in the text is not defined, this will crash. Variables to be |
| // substituted are identified by their names surrounded by delimiter |
| // characters (as given to the constructor). The variable bindings are |
| // defined by the given map. |
| void Print(const map<string, string>& variables, const char* text); |
| |
| // Like the first Print(), except the substitutions are given as parameters. |
| void Print(const char* text); |
| // Like the first Print(), except the substitutions are given as parameters. |
| void Print(const char* text, const char* variable, const string& value); |
| // Like the first Print(), except the substitutions are given as parameters. |
| void Print(const char* text, const char* variable1, const string& value1, |
| const char* variable2, const string& value2); |
| // TODO(kenton): Overloaded versions with more variables? Two seems |
| // to be enough. |
| |
| // Indent text by two spaces. After calling Indent(), two spaces will be |
| // inserted at the beginning of each line of text. Indent() may be called |
| // multiple times to produce deeper indents. |
| void Indent(); |
| |
| // Reduces the current indent level by two spaces, or crashes if the indent |
| // level is zero. |
| void Outdent(); |
| |
| // True if any write to the underlying stream failed. (We don't just |
| // crash in this case because this is an I/O failure, not a programming |
| // error.) |
| bool failed() const { return failed_; } |
| |
| private: |
| // Write some text to the output buffer. |
| void Write(const char* data, int size); |
| |
| const char variable_delimiter_; |
| |
| ZeroCopyOutputStream* const output_; |
| char* buffer_; |
| int buffer_size_; |
| |
| string indent_; |
| bool at_start_of_line_; |
| bool failed_; |
| |
| GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Printer); |
| }; |
| |
| } // namespace io |
| } // namespace protobuf |
| |
| } // namespace google |
| #endif // GOOGLE_PROTOBUF_IO_PRINTER_H__ |