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 // Author: kenton (at) google.com (Kenton Varda) 32 // Based on original Protocol Buffers design by 33 // Sanjay Ghemawat, Jeff Dean, and others. 34 // 35 // This header is logically internal, but is made public because it is used 36 // from protocol-compiler-generated code, which may reside in other components. 37 38 #ifndef GOOGLE_PROTOBUF_GENERATED_MESSAGE_REFLECTION_H__ 39 #define GOOGLE_PROTOBUF_GENERATED_MESSAGE_REFLECTION_H__ 40 41 #include <string> 42 #include <vector> 43 #include <google/protobuf/stubs/common.h> 44 // TODO(jasonh): Remove this once the compiler change to directly include this 45 // is released to components. 46 #include <google/protobuf/generated_enum_reflection.h> 47 #include <google/protobuf/message.h> 48 #include <google/protobuf/unknown_field_set.h> 49 50 51 namespace google { 52 namespace upb { 53 namespace google_opensource { 54 class GMR_Handlers; 55 } // namespace google_opensource 56 } // namespace upb 57 58 namespace protobuf { 59 class DescriptorPool; 60 } 61 62 namespace protobuf { 63 namespace internal { 64 class DefaultEmptyOneof; 65 66 // Defined in this file. 67 class GeneratedMessageReflection; 68 69 // Defined in other files. 70 class ExtensionSet; // extension_set.h 71 72 // THIS CLASS IS NOT INTENDED FOR DIRECT USE. It is intended for use 73 // by generated code. This class is just a big hack that reduces code 74 // size. 75 // 76 // A GeneratedMessageReflection is an implementation of Reflection 77 // which expects all fields to be backed by simple variables located in 78 // memory. The locations are given using a base pointer and a set of 79 // offsets. 80 // 81 // It is required that the user represents fields of each type in a standard 82 // way, so that GeneratedMessageReflection can cast the void* pointer to 83 // the appropriate type. For primitive fields and string fields, each field 84 // should be represented using the obvious C++ primitive type. Enums and 85 // Messages are different: 86 // - Singular Message fields are stored as a pointer to a Message. These 87 // should start out NULL, except for in the default instance where they 88 // should start out pointing to other default instances. 89 // - Enum fields are stored as an int. This int must always contain 90 // a valid value, such that EnumDescriptor::FindValueByNumber() would 91 // not return NULL. 92 // - Repeated fields are stored as RepeatedFields or RepeatedPtrFields 93 // of whatever type the individual field would be. Strings and 94 // Messages use RepeatedPtrFields while everything else uses 95 // RepeatedFields. 96 class LIBPROTOBUF_EXPORT GeneratedMessageReflection : public Reflection { 97 public: 98 // Constructs a GeneratedMessageReflection. 99 // Parameters: 100 // descriptor: The descriptor for the message type being implemented. 101 // default_instance: The default instance of the message. This is only 102 // used to obtain pointers to default instances of embedded 103 // messages, which GetMessage() will return if the particular 104 // sub-message has not been initialized yet. (Thus, all 105 // embedded message fields *must* have non-NULL pointers 106 // in the default instance.) 107 // offsets: An array of ints giving the byte offsets, relative to 108 // the start of the message object, of each field. These can 109 // be computed at compile time using the 110 // GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET() macro, defined 111 // below. 112 // has_bits_offset: Offset in the message of an array of uint32s of size 113 // descriptor->field_count()/32, rounded up. This is a 114 // bitfield where each bit indicates whether or not the 115 // corresponding field of the message has been initialized. 116 // The bit for field index i is obtained by the expression: 117 // has_bits[i / 32] & (1 << (i % 32)) 118 // unknown_fields_offset: Offset in the message of the UnknownFieldSet for 119 // the message. 120 // extensions_offset: Offset in the message of the ExtensionSet for the 121 // message, or -1 if the message type has no extension 122 // ranges. 123 // pool: DescriptorPool to search for extension definitions. Only 124 // used by FindKnownExtensionByName() and 125 // FindKnownExtensionByNumber(). 126 // factory: MessageFactory to use to construct extension messages. 127 // object_size: The size of a message object of this type, as measured 128 // by sizeof(). 129 GeneratedMessageReflection(const Descriptor* descriptor, 130 const Message* default_instance, 131 const int offsets[], 132 int has_bits_offset, 133 int unknown_fields_offset, 134 int extensions_offset, 135 const DescriptorPool* pool, 136 MessageFactory* factory, 137 int object_size); 138 139 // Similar with the construction above. Call this construction if the 140 // message has oneof definition. 141 // Parameters: 142 // offsets: An array of ints giving the byte offsets. 143 // For each oneof field, the offset is relative to the 144 // default_oneof_instance. These can be computed at compile 145 // time using the 146 // PROTO2_GENERATED_DEFAULT_ONEOF_FIELD_OFFSET() macro. 147 // For each none oneof field, the offset is related to 148 // the start of the message object. These can be computed 149 // at compile time using the 150 // GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET() macro. 151 // Besides offsets for all fields, this array also contains 152 // offsets for oneof unions. The offset of the i-th oneof 153 // union is offsets[descriptor->field_count() + i]. 154 // default_oneof_instance: The default instance of the oneofs. It is a 155 // struct holding the default value of all oneof fields 156 // for this message. It is only used to obtain pointers 157 // to default instances of oneof fields, which Get 158 // methods will return if the field is not set. 159 // oneof_case_offset: Offset in the message of an array of uint32s of 160 // size descriptor->oneof_decl_count(). Each uint32 161 // indicates what field is set for each oneof. 162 // other parameters are the same with the construction above. 163 GeneratedMessageReflection(const Descriptor* descriptor, 164 const Message* default_instance, 165 const int offsets[], 166 int has_bits_offset, 167 int unknown_fields_offset, 168 int extensions_offset, 169 const void* default_oneof_instance, 170 int oneof_case_offset, 171 const DescriptorPool* pool, 172 MessageFactory* factory, 173 int object_size); 174 ~GeneratedMessageReflection(); 175 176 // implements Reflection ------------------------------------------- 177 178 const UnknownFieldSet& GetUnknownFields(const Message& message) const; 179 UnknownFieldSet* MutableUnknownFields(Message* message) const; 180 181 int SpaceUsed(const Message& message) const; 182 183 bool HasField(const Message& message, const FieldDescriptor* field) const; 184 int FieldSize(const Message& message, const FieldDescriptor* field) const; 185 void ClearField(Message* message, const FieldDescriptor* field) const; 186 bool HasOneof(const Message& message, 187 const OneofDescriptor* oneof_descriptor) const; 188 void ClearOneof(Message* message, const OneofDescriptor* field) const; 189 void RemoveLast(Message* message, const FieldDescriptor* field) const; 190 Message* ReleaseLast(Message* message, const FieldDescriptor* field) const; 191 void Swap(Message* message1, Message* message2) const; 192 void SwapFields(Message* message1, Message* message2, 193 const vector<const FieldDescriptor*>& fields) const; 194 void SwapElements(Message* message, const FieldDescriptor* field, 195 int index1, int index2) const; 196 void ListFields(const Message& message, 197 vector<const FieldDescriptor*>* output) const; 198 199 int32 GetInt32 (const Message& message, 200 const FieldDescriptor* field) const; 201 int64 GetInt64 (const Message& message, 202 const FieldDescriptor* field) const; 203 uint32 GetUInt32(const Message& message, 204 const FieldDescriptor* field) const; 205 uint64 GetUInt64(const Message& message, 206 const FieldDescriptor* field) const; 207 float GetFloat (const Message& message, 208 const FieldDescriptor* field) const; 209 double GetDouble(const Message& message, 210 const FieldDescriptor* field) const; 211 bool GetBool (const Message& message, 212 const FieldDescriptor* field) const; 213 string GetString(const Message& message, 214 const FieldDescriptor* field) const; 215 const string& GetStringReference(const Message& message, 216 const FieldDescriptor* field, 217 string* scratch) const; 218 const EnumValueDescriptor* GetEnum(const Message& message, 219 const FieldDescriptor* field) const; 220 const Message& GetMessage(const Message& message, 221 const FieldDescriptor* field, 222 MessageFactory* factory = NULL) const; 223 224 const FieldDescriptor* GetOneofFieldDescriptor( 225 const Message& message, 226 const OneofDescriptor* oneof_descriptor) const; 227 228 public: 229 void SetInt32 (Message* message, 230 const FieldDescriptor* field, int32 value) const; 231 void SetInt64 (Message* message, 232 const FieldDescriptor* field, int64 value) const; 233 void SetUInt32(Message* message, 234 const FieldDescriptor* field, uint32 value) const; 235 void SetUInt64(Message* message, 236 const FieldDescriptor* field, uint64 value) const; 237 void SetFloat (Message* message, 238 const FieldDescriptor* field, float value) const; 239 void SetDouble(Message* message, 240 const FieldDescriptor* field, double value) const; 241 void SetBool (Message* message, 242 const FieldDescriptor* field, bool value) const; 243 void SetString(Message* message, 244 const FieldDescriptor* field, 245 const string& value) const; 246 void SetEnum (Message* message, const FieldDescriptor* field, 247 const EnumValueDescriptor* value) const; 248 Message* MutableMessage(Message* message, const FieldDescriptor* field, 249 MessageFactory* factory = NULL) const; 250 void SetAllocatedMessage(Message* message, 251 Message* sub_message, 252 const FieldDescriptor* field) const; 253 Message* ReleaseMessage(Message* message, const FieldDescriptor* field, 254 MessageFactory* factory = NULL) const; 255 256 int32 GetRepeatedInt32 (const Message& message, 257 const FieldDescriptor* field, int index) const; 258 int64 GetRepeatedInt64 (const Message& message, 259 const FieldDescriptor* field, int index) const; 260 uint32 GetRepeatedUInt32(const Message& message, 261 const FieldDescriptor* field, int index) const; 262 uint64 GetRepeatedUInt64(const Message& message, 263 const FieldDescriptor* field, int index) const; 264 float GetRepeatedFloat (const Message& message, 265 const FieldDescriptor* field, int index) const; 266 double GetRepeatedDouble(const Message& message, 267 const FieldDescriptor* field, int index) const; 268 bool GetRepeatedBool (const Message& message, 269 const FieldDescriptor* field, int index) const; 270 string GetRepeatedString(const Message& message, 271 const FieldDescriptor* field, int index) const; 272 const string& GetRepeatedStringReference(const Message& message, 273 const FieldDescriptor* field, 274 int index, string* scratch) const; 275 const EnumValueDescriptor* GetRepeatedEnum(const Message& message, 276 const FieldDescriptor* field, 277 int index) const; 278 const Message& GetRepeatedMessage(const Message& message, 279 const FieldDescriptor* field, 280 int index) const; 281 282 // Set the value of a field. 283 void SetRepeatedInt32 (Message* message, 284 const FieldDescriptor* field, int index, int32 value) const; 285 void SetRepeatedInt64 (Message* message, 286 const FieldDescriptor* field, int index, int64 value) const; 287 void SetRepeatedUInt32(Message* message, 288 const FieldDescriptor* field, int index, uint32 value) const; 289 void SetRepeatedUInt64(Message* message, 290 const FieldDescriptor* field, int index, uint64 value) const; 291 void SetRepeatedFloat (Message* message, 292 const FieldDescriptor* field, int index, float value) const; 293 void SetRepeatedDouble(Message* message, 294 const FieldDescriptor* field, int index, double value) const; 295 void SetRepeatedBool (Message* message, 296 const FieldDescriptor* field, int index, bool value) const; 297 void SetRepeatedString(Message* message, 298 const FieldDescriptor* field, int index, 299 const string& value) const; 300 void SetRepeatedEnum(Message* message, const FieldDescriptor* field, 301 int index, const EnumValueDescriptor* value) const; 302 // Get a mutable pointer to a field with a message type. 303 Message* MutableRepeatedMessage(Message* message, 304 const FieldDescriptor* field, 305 int index) const; 306 307 void AddInt32 (Message* message, 308 const FieldDescriptor* field, int32 value) const; 309 void AddInt64 (Message* message, 310 const FieldDescriptor* field, int64 value) const; 311 void AddUInt32(Message* message, 312 const FieldDescriptor* field, uint32 value) const; 313 void AddUInt64(Message* message, 314 const FieldDescriptor* field, uint64 value) const; 315 void AddFloat (Message* message, 316 const FieldDescriptor* field, float value) const; 317 void AddDouble(Message* message, 318 const FieldDescriptor* field, double value) const; 319 void AddBool (Message* message, 320 const FieldDescriptor* field, bool value) const; 321 void AddString(Message* message, 322 const FieldDescriptor* field, const string& value) const; 323 void AddEnum(Message* message, 324 const FieldDescriptor* field, 325 const EnumValueDescriptor* value) const; 326 Message* AddMessage(Message* message, const FieldDescriptor* field, 327 MessageFactory* factory = NULL) const; 328 329 const FieldDescriptor* FindKnownExtensionByName(const string& name) const; 330 const FieldDescriptor* FindKnownExtensionByNumber(int number) const; 331 332 protected: 333 virtual void* MutableRawRepeatedField( 334 Message* message, const FieldDescriptor* field, FieldDescriptor::CppType, 335 int ctype, const Descriptor* desc) const; 336 337 private: 338 friend class GeneratedMessage; 339 340 // To parse directly into a proto2 generated class, the class GMR_Handlers 341 // needs access to member offsets and hasbits. 342 friend class LIBPROTOBUF_EXPORT upb::google_opensource::GMR_Handlers; 343 344 const Descriptor* descriptor_; 345 const Message* default_instance_; 346 const void* default_oneof_instance_; 347 const int* offsets_; 348 349 int has_bits_offset_; 350 int oneof_case_offset_; 351 int unknown_fields_offset_; 352 int extensions_offset_; 353 int object_size_; 354 355 const DescriptorPool* descriptor_pool_; 356 MessageFactory* message_factory_; 357 358 template <typename Type> 359 inline const Type& GetRaw(const Message& message, 360 const FieldDescriptor* field) const; 361 template <typename Type> 362 inline Type* MutableRaw(Message* message, 363 const FieldDescriptor* field) const; 364 template <typename Type> 365 inline const Type& DefaultRaw(const FieldDescriptor* field) const; 366 template <typename Type> 367 inline const Type& DefaultOneofRaw(const FieldDescriptor* field) const; 368 369 inline const uint32* GetHasBits(const Message& message) const; 370 inline uint32* MutableHasBits(Message* message) const; 371 inline uint32 GetOneofCase( 372 const Message& message, 373 const OneofDescriptor* oneof_descriptor) const; 374 inline uint32* MutableOneofCase( 375 Message* message, 376 const OneofDescriptor* oneof_descriptor) const; 377 inline const ExtensionSet& GetExtensionSet(const Message& message) const; 378 inline ExtensionSet* MutableExtensionSet(Message* message) const; 379 380 inline bool HasBit(const Message& message, 381 const FieldDescriptor* field) const; 382 inline void SetBit(Message* message, 383 const FieldDescriptor* field) const; 384 inline void ClearBit(Message* message, 385 const FieldDescriptor* field) const; 386 inline void SwapBit(Message* message1, 387 Message* message2, 388 const FieldDescriptor* field) const; 389 390 // This function only swaps the field. Should swap corresponding has_bit 391 // before or after using this function. 392 void SwapField(Message* message1, 393 Message* message2, 394 const FieldDescriptor* field) const; 395 396 void SwapOneofField(Message* message1, 397 Message* message2, 398 const OneofDescriptor* oneof_descriptor) const; 399 400 inline bool HasOneofField(const Message& message, 401 const FieldDescriptor* field) const; 402 inline void SetOneofCase(Message* message, 403 const FieldDescriptor* field) const; 404 inline void ClearOneofField(Message* message, 405 const FieldDescriptor* field) const; 406 407 template <typename Type> 408 inline const Type& GetField(const Message& message, 409 const FieldDescriptor* field) const; 410 template <typename Type> 411 inline void SetField(Message* message, 412 const FieldDescriptor* field, const Type& value) const; 413 template <typename Type> 414 inline Type* MutableField(Message* message, 415 const FieldDescriptor* field) const; 416 template <typename Type> 417 inline const Type& GetRepeatedField(const Message& message, 418 const FieldDescriptor* field, 419 int index) const; 420 template <typename Type> 421 inline const Type& GetRepeatedPtrField(const Message& message, 422 const FieldDescriptor* field, 423 int index) const; 424 template <typename Type> 425 inline void SetRepeatedField(Message* message, 426 const FieldDescriptor* field, int index, 427 Type value) const; 428 template <typename Type> 429 inline Type* MutableRepeatedField(Message* message, 430 const FieldDescriptor* field, 431 int index) const; 432 template <typename Type> 433 inline void AddField(Message* message, 434 const FieldDescriptor* field, const Type& value) const; 435 template <typename Type> 436 inline Type* AddField(Message* message, 437 const FieldDescriptor* field) const; 438 439 int GetExtensionNumberOrDie(const Descriptor* type) const; 440 441 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(GeneratedMessageReflection); 442 }; 443 444 // Returns the offset of the given field within the given aggregate type. 445 // This is equivalent to the ANSI C offsetof() macro. However, according 446 // to the C++ standard, offsetof() only works on POD types, and GCC 447 // enforces this requirement with a warning. In practice, this rule is 448 // unnecessarily strict; there is probably no compiler or platform on 449 // which the offsets of the direct fields of a class are non-constant. 450 // Fields inherited from superclasses *can* have non-constant offsets, 451 // but that's not what this macro will be used for. 452 // 453 // Note that we calculate relative to the pointer value 16 here since if we 454 // just use zero, GCC complains about dereferencing a NULL pointer. We 455 // choose 16 rather than some other number just in case the compiler would 456 // be confused by an unaligned pointer. 457 #define GOOGLE_PROTOBUF_GENERATED_MESSAGE_FIELD_OFFSET(TYPE, FIELD) \ 458 static_cast<int>( \ 459 reinterpret_cast<const char*>( \ 460 &reinterpret_cast<const TYPE*>(16)->FIELD) - \ 461 reinterpret_cast<const char*>(16)) 462 463 #define PROTO2_GENERATED_DEFAULT_ONEOF_FIELD_OFFSET(ONEOF, FIELD) \ 464 static_cast<int>( \ 465 reinterpret_cast<const char*>(&(ONEOF->FIELD)) \ 466 - reinterpret_cast<const char*>(ONEOF)) 467 468 // There are some places in proto2 where dynamic_cast would be useful as an 469 // optimization. For example, take Message::MergeFrom(const Message& other). 470 // For a given generated message FooMessage, we generate these two methods: 471 // void MergeFrom(const FooMessage& other); 472 // void MergeFrom(const Message& other); 473 // The former method can be implemented directly in terms of FooMessage's 474 // inline accessors, but the latter method must work with the reflection 475 // interface. However, if the parameter to the latter method is actually of 476 // type FooMessage, then we'd like to be able to just call the other method 477 // as an optimization. So, we use dynamic_cast to check this. 478 // 479 // That said, dynamic_cast requires RTTI, which many people like to disable 480 // for performance and code size reasons. When RTTI is not available, we 481 // still need to produce correct results. So, in this case we have to fall 482 // back to using reflection, which is what we would have done anyway if the 483 // objects were not of the exact same class. 484 // 485 // dynamic_cast_if_available() implements this logic. If RTTI is 486 // enabled, it does a dynamic_cast. If RTTI is disabled, it just returns 487 // NULL. 488 // 489 // If you need to compile without RTTI, simply #define GOOGLE_PROTOBUF_NO_RTTI. 490 // On MSVC, this should be detected automatically. 491 template<typename To, typename From> 492 inline To dynamic_cast_if_available(From from) { 493 #if defined(GOOGLE_PROTOBUF_NO_RTTI) || (defined(_MSC_VER)&&!defined(_CPPRTTI)) 494 return NULL; 495 #else 496 return dynamic_cast<To>(from); 497 #endif 498 } 499 500 } // namespace internal 501 } // namespace protobuf 502 503 } // namespace google 504 #endif // GOOGLE_PROTOBUF_GENERATED_MESSAGE_REFLECTION_H__ 505
