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 #ifndef GOOGLE_PROTOBUF_UTIL_INTERNAL_OBJECT_WRITER_H__ 32 #define GOOGLE_PROTOBUF_UTIL_INTERNAL_OBJECT_WRITER_H__ 33 34 #include <cstdint> 35 36 #include <google/protobuf/stubs/common.h> 37 #include <google/protobuf/stubs/strutil.h> 38 39 // Must be included last. 40 #include <google/protobuf/port_def.inc> 41 42 namespace google { 43 namespace protobuf { 44 namespace util { 45 namespace converter { 46 47 48 class DataPiece; 49 50 // An ObjectWriter is an interface for writing a stream of events 51 // representing objects and collections. Implementation of this 52 // interface can be used to write an object stream to an in-memory 53 // structure, protobufs, JSON, XML, or any other output format 54 // desired. The ObjectSource interface is typically used as the 55 // source of an object stream. 56 // 57 // See JsonObjectWriter for a sample implementation of ObjectWriter 58 // and its use. 59 // 60 // Derived classes could be thread-unsafe. 61 // 62 // TODO(xinb): seems like a prime candidate to apply the RAII paradigm 63 // and get rid the need to call EndXXX(). 64 class PROTOBUF_EXPORT ObjectWriter { 65 public: ~ObjectWriter()66 virtual ~ObjectWriter() {} 67 68 // Starts an object. If the name is empty, the object will not be named. 69 virtual ObjectWriter* StartObject(StringPiece name) = 0; 70 71 // Ends an object. 72 virtual ObjectWriter* EndObject() = 0; 73 74 // Starts a list. If the name is empty, the list will not be named. 75 virtual ObjectWriter* StartList(StringPiece name) = 0; 76 77 // Ends a list. 78 virtual ObjectWriter* EndList() = 0; 79 80 // Renders a boolean value. 81 virtual ObjectWriter* RenderBool(StringPiece name, bool value) = 0; 82 83 // Renders an 32-bit integer value. 84 virtual ObjectWriter* RenderInt32(StringPiece name, int32_t value) = 0; 85 86 // Renders an 32-bit unsigned integer value. 87 virtual ObjectWriter* RenderUint32(StringPiece name, 88 uint32_t value) = 0; 89 90 // Renders a 64-bit integer value. 91 virtual ObjectWriter* RenderInt64(StringPiece name, int64_t value) = 0; 92 93 // Renders an 64-bit unsigned integer value. 94 virtual ObjectWriter* RenderUint64(StringPiece name, 95 uint64_t value) = 0; 96 97 98 // Renders a double value. 99 virtual ObjectWriter* RenderDouble(StringPiece name, double value) = 0; 100 // Renders a float value. 101 virtual ObjectWriter* RenderFloat(StringPiece name, float value) = 0; 102 103 // Renders a StringPiece value. This is for rendering strings. 104 virtual ObjectWriter* RenderString(StringPiece name, 105 StringPiece value) = 0; 106 107 // Renders a bytes value. 108 virtual ObjectWriter* RenderBytes(StringPiece name, StringPiece value) = 0; 109 110 // Renders a Null value. 111 virtual ObjectWriter* RenderNull(StringPiece name) = 0; 112 113 114 // Renders a DataPiece object to a ObjectWriter. 115 static void RenderDataPieceTo(const DataPiece& data, StringPiece name, 116 ObjectWriter* ow); 117 118 119 // Indicates whether this ObjectWriter has completed writing the root message, 120 // usually this means writing of one complete object. Subclasses must override 121 // this behavior appropriately. done()122 virtual bool done() { return false; } 123 set_use_strict_base64_decoding(bool value)124 void set_use_strict_base64_decoding(bool value) { 125 use_strict_base64_decoding_ = value; 126 } 127 use_strict_base64_decoding()128 bool use_strict_base64_decoding() const { 129 return use_strict_base64_decoding_; 130 } 131 132 protected: ObjectWriter()133 ObjectWriter() : use_strict_base64_decoding_(true) {} 134 135 private: 136 // If set to true, we use the stricter version of base64 decoding for byte 137 // fields by making sure decoded version encodes back to the original string. 138 bool use_strict_base64_decoding_; 139 140 // Do not add any data members to this class. 141 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ObjectWriter); 142 }; 143 144 } // namespace converter 145 } // namespace util 146 } // namespace protobuf 147 } // namespace google 148 149 #include <google/protobuf/port_undef.inc> 150 151 #endif // GOOGLE_PROTOBUF_UTIL_INTERNAL_OBJECT_WRITER_H__ 152