1 // Protocol Buffers - Google's data interchange format 2 // Copyright 2008 Google Inc. All rights reserved. 3 // http://code.google.com/p/protobuf/ 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 (at) google.com (Kenton Varda) 32 // atenasio (at) google.com (Chris Atenasio) (ZigZag transform) 33 // Based on original Protocol Buffers design by 34 // Sanjay Ghemawat, Jeff Dean, and others. 35 // 36 // This header is logically internal, but is made public because it is used 37 // from protocol-compiler-generated code, which may reside in other components. 38 39 #ifndef GOOGLE_PROTOBUF_WIRE_FORMAT_H__ 40 #define GOOGLE_PROTOBUF_WIRE_FORMAT_H__ 41 42 #include <string> 43 #include <google/protobuf/stubs/common.h> 44 #include <google/protobuf/descriptor.pb.h> 45 #include <google/protobuf/descriptor.h> 46 #include <google/protobuf/message.h> 47 #include <google/protobuf/wire_format_lite.h> 48 49 // Do UTF-8 validation on string type in Debug build only 50 #ifndef NDEBUG 51 #define GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED 52 #endif 53 54 namespace google { 55 namespace protobuf { 56 namespace io { 57 class CodedInputStream; // coded_stream.h 58 class CodedOutputStream; // coded_stream.h 59 } 60 class UnknownFieldSet; // unknown_field_set.h 61 } 62 63 namespace protobuf { 64 namespace internal { 65 66 // This class is for internal use by the protocol buffer library and by 67 // protocol-complier-generated message classes. It must not be called 68 // directly by clients. 69 // 70 // This class contains code for implementing the binary protocol buffer 71 // wire format via reflection. The WireFormatLite class implements the 72 // non-reflection based routines. 73 // 74 // This class is really a namespace that contains only static methods 75 class LIBPROTOBUF_EXPORT WireFormat { 76 public: 77 78 // Given a field return its WireType 79 static inline WireFormatLite::WireType WireTypeForField( 80 const FieldDescriptor* field); 81 82 // Given a FieldSescriptor::Type return its WireType 83 static inline WireFormatLite::WireType WireTypeForFieldType( 84 FieldDescriptor::Type type); 85 86 // Compute the byte size of a tag. For groups, this includes both the start 87 // and end tags. 88 static inline int TagSize(int field_number, FieldDescriptor::Type type); 89 90 // These procedures can be used to implement the methods of Message which 91 // handle parsing and serialization of the protocol buffer wire format 92 // using only the Reflection interface. When you ask the protocol 93 // compiler to optimize for code size rather than speed, it will implement 94 // those methods in terms of these procedures. Of course, these are much 95 // slower than the specialized implementations which the protocol compiler 96 // generates when told to optimize for speed. 97 98 // Read a message in protocol buffer wire format. 99 // 100 // This procedure reads either to the end of the input stream or through 101 // a WIRETYPE_END_GROUP tag ending the message, whichever comes first. 102 // It returns false if the input is invalid. 103 // 104 // Required fields are NOT checked by this method. You must call 105 // IsInitialized() on the resulting message yourself. 106 static bool ParseAndMergePartial(io::CodedInputStream* input, 107 Message* message); 108 109 // Serialize a message in protocol buffer wire format. 110 // 111 // Any embedded messages within the message must have their correct sizes 112 // cached. However, the top-level message need not; its size is passed as 113 // a parameter to this procedure. 114 // 115 // These return false iff the underlying stream returns a write error. 116 static void SerializeWithCachedSizes( 117 const Message& message, 118 int size, io::CodedOutputStream* output); 119 120 // Implements Message::ByteSize() via reflection. WARNING: The result 121 // of this method is *not* cached anywhere. However, all embedded messages 122 // will have their ByteSize() methods called, so their sizes will be cached. 123 // Therefore, calling this method is sufficient to allow you to call 124 // WireFormat::SerializeWithCachedSizes() on the same object. 125 static int ByteSize(const Message& message); 126 127 // ----------------------------------------------------------------- 128 // Helpers for dealing with unknown fields 129 130 // Skips a field value of the given WireType. The input should start 131 // positioned immediately after the tag. If unknown_fields is non-NULL, 132 // the contents of the field will be added to it. 133 static bool SkipField(io::CodedInputStream* input, uint32 tag, 134 UnknownFieldSet* unknown_fields); 135 136 // Reads and ignores a message from the input. If unknown_fields is non-NULL, 137 // the contents will be added to it. 138 static bool SkipMessage(io::CodedInputStream* input, 139 UnknownFieldSet* unknown_fields); 140 141 // Write the contents of an UnknownFieldSet to the output. 142 static void SerializeUnknownFields(const UnknownFieldSet& unknown_fields, 143 io::CodedOutputStream* output); 144 // Same as above, except writing directly to the provided buffer. 145 // Requires that the buffer have sufficient capacity for 146 // ComputeUnknownFieldsSize(unknown_fields). 147 // 148 // Returns a pointer past the last written byte. 149 static uint8* SerializeUnknownFieldsToArray( 150 const UnknownFieldSet& unknown_fields, 151 uint8* target); 152 153 // Same thing except for messages that have the message_set_wire_format 154 // option. 155 static void SerializeUnknownMessageSetItems( 156 const UnknownFieldSet& unknown_fields, 157 io::CodedOutputStream* output); 158 // Same as above, except writing directly to the provided buffer. 159 // Requires that the buffer have sufficient capacity for 160 // ComputeUnknownMessageSetItemsSize(unknown_fields). 161 // 162 // Returns a pointer past the last written byte. 163 static uint8* SerializeUnknownMessageSetItemsToArray( 164 const UnknownFieldSet& unknown_fields, 165 uint8* target); 166 167 // Compute the size of the UnknownFieldSet on the wire. 168 static int ComputeUnknownFieldsSize(const UnknownFieldSet& unknown_fields); 169 170 // Same thing except for messages that have the message_set_wire_format 171 // option. 172 static int ComputeUnknownMessageSetItemsSize( 173 const UnknownFieldSet& unknown_fields); 174 175 176 // Helper functions for encoding and decoding tags. (Inlined below and in 177 // _inl.h) 178 // 179 // This is different from MakeTag(field->number(), field->type()) in the case 180 // of packed repeated fields. 181 static uint32 MakeTag(const FieldDescriptor* field); 182 183 // Parse a single field. The input should start out positioned immidately 184 // after the tag. 185 static bool ParseAndMergeField( 186 uint32 tag, 187 const FieldDescriptor* field, // May be NULL for unknown 188 Message* message, 189 io::CodedInputStream* input); 190 191 // Serialize a single field. 192 static void SerializeFieldWithCachedSizes( 193 const FieldDescriptor* field, // Cannot be NULL 194 const Message& message, 195 io::CodedOutputStream* output); 196 197 // Compute size of a single field. If the field is a message type, this 198 // will call ByteSize() for the embedded message, insuring that it caches 199 // its size. 200 static int FieldByteSize( 201 const FieldDescriptor* field, // Cannot be NULL 202 const Message& message); 203 204 // Parse/serialize a MessageSet::Item group. Used with messages that use 205 // opion message_set_wire_format = true. 206 static bool ParseAndMergeMessageSetItem( 207 io::CodedInputStream* input, 208 Message* message); 209 static void SerializeMessageSetItemWithCachedSizes( 210 const FieldDescriptor* field, 211 const Message& message, 212 io::CodedOutputStream* output); 213 static int MessageSetItemByteSize( 214 const FieldDescriptor* field, 215 const Message& message); 216 217 // Computes the byte size of a field, excluding tags. For packed fields, it 218 // only includes the size of the raw data, and not the size of the total 219 // length, but for other length-delimited types, the size of the length is 220 // included. 221 static int FieldDataOnlyByteSize( 222 const FieldDescriptor* field, // Cannot be NULL 223 const Message& message); 224 225 enum Operation { 226 PARSE, 227 SERIALIZE, 228 }; 229 230 // Verifies that a string field is valid UTF8, logging an error if not. 231 static void VerifyUTF8String(const char* data, int size, Operation op); 232 233 private: 234 // Verifies that a string field is valid UTF8, logging an error if not. 235 static void VerifyUTF8StringFallback( 236 const char* data, 237 int size, 238 Operation op); 239 240 241 242 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(WireFormat); 243 }; 244 245 // Subclass of FieldSkipper which saves skipped fields to an UnknownFieldSet. 246 class LIBPROTOBUF_EXPORT UnknownFieldSetFieldSkipper : public FieldSkipper { 247 public: 248 UnknownFieldSetFieldSkipper(UnknownFieldSet* unknown_fields) 249 : unknown_fields_(unknown_fields) {} 250 virtual ~UnknownFieldSetFieldSkipper() {} 251 252 // implements FieldSkipper ----------------------------------------- 253 virtual bool SkipField(io::CodedInputStream* input, uint32 tag); 254 virtual bool SkipMessage(io::CodedInputStream* input); 255 virtual void SkipUnknownEnum(int field_number, int value); 256 257 protected: 258 UnknownFieldSet* unknown_fields_; 259 }; 260 261 // inline methods ==================================================== 262 263 inline WireFormatLite::WireType WireFormat::WireTypeForField( 264 const FieldDescriptor* field) { 265 if (field->options().packed()) { 266 return WireFormatLite::WIRETYPE_LENGTH_DELIMITED; 267 } else { 268 return WireTypeForFieldType(field->type()); 269 } 270 } 271 272 inline WireFormatLite::WireType WireFormat::WireTypeForFieldType( 273 FieldDescriptor::Type type) { 274 // Some compilers don't like enum -> enum casts, so we implicit_cast to 275 // int first. 276 return WireFormatLite::WireTypeForFieldType( 277 static_cast<WireFormatLite::FieldType>( 278 implicit_cast<int>(type))); 279 } 280 281 inline uint32 WireFormat::MakeTag(const FieldDescriptor* field) { 282 return WireFormatLite::MakeTag(field->number(), WireTypeForField(field)); 283 } 284 285 inline int WireFormat::TagSize(int field_number, FieldDescriptor::Type type) { 286 // Some compilers don't like enum -> enum casts, so we implicit_cast to 287 // int first. 288 return WireFormatLite::TagSize(field_number, 289 static_cast<WireFormatLite::FieldType>( 290 implicit_cast<int>(type))); 291 } 292 293 inline void WireFormat::VerifyUTF8String(const char* data, int size, 294 WireFormat::Operation op) { 295 #ifdef GOOGLE_PROTOBUF_UTF8_VALIDATION_ENABLED 296 WireFormat::VerifyUTF8StringFallback(data, size, op); 297 #else 298 // Avoid the compiler warning about unsued variables. 299 (void)data; (void)size; (void)op; 300 #endif 301 } 302 303 304 } // namespace internal 305 } // namespace protobuf 306 307 } // namespace google 308 #endif // GOOGLE_PROTOBUF_WIRE_FORMAT_H__ 309