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 // 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_EXTENSION_SET_H__ 39 #define GOOGLE_PROTOBUF_EXTENSION_SET_H__ 40 41 #include <vector> 42 #include <map> 43 #include <utility> 44 #include <string> 45 46 47 #include <google/protobuf/stubs/common.h> 48 49 namespace google { 50 51 namespace protobuf { 52 class Descriptor; // descriptor.h 53 class FieldDescriptor; // descriptor.h 54 class DescriptorPool; // descriptor.h 55 class MessageLite; // message_lite.h 56 class Message; // message.h 57 class MessageFactory; // message.h 58 class UnknownFieldSet; // unknown_field_set.h 59 namespace io { 60 class CodedInputStream; // coded_stream.h 61 class CodedOutputStream; // coded_stream.h 62 } 63 namespace internal { 64 class FieldSkipper; // wire_format_lite.h 65 class RepeatedPtrFieldBase; // repeated_field.h 66 } 67 template <typename Element> class RepeatedField; // repeated_field.h 68 template <typename Element> class RepeatedPtrField; // repeated_field.h 69 } 70 71 namespace protobuf { 72 namespace internal { 73 74 // Used to store values of type WireFormatLite::FieldType without having to 75 // #include wire_format_lite.h. Also, ensures that we use only one byte to 76 // store these values, which is important to keep the layout of 77 // ExtensionSet::Extension small. 78 typedef uint8 FieldType; 79 80 // A function which, given an integer value, returns true if the number 81 // matches one of the defined values for the corresponding enum type. This 82 // is used with RegisterEnumExtension, below. 83 typedef bool EnumValidityFunc(int number); 84 85 // Version of the above which takes an argument. This is needed to deal with 86 // extensions that are not compiled in. 87 typedef bool EnumValidityFuncWithArg(const void* arg, int number); 88 89 // Information about a registered extension. 90 struct ExtensionInfo { 91 inline ExtensionInfo() {} 92 inline ExtensionInfo(FieldType type_param, bool isrepeated, bool ispacked) 93 : type(type_param), is_repeated(isrepeated), is_packed(ispacked), 94 descriptor(NULL) {} 95 96 FieldType type; 97 bool is_repeated; 98 bool is_packed; 99 100 struct EnumValidityCheck { 101 EnumValidityFuncWithArg* func; 102 const void* arg; 103 }; 104 105 union { 106 EnumValidityCheck enum_validity_check; 107 const MessageLite* message_prototype; 108 }; 109 110 // The descriptor for this extension, if one exists and is known. May be 111 // NULL. Must not be NULL if the descriptor for the extension does not 112 // live in the same pool as the descriptor for the containing type. 113 const FieldDescriptor* descriptor; 114 }; 115 116 // Abstract interface for an object which looks up extension definitions. Used 117 // when parsing. 118 class LIBPROTOBUF_EXPORT ExtensionFinder { 119 public: 120 virtual ~ExtensionFinder(); 121 122 // Find the extension with the given containing type and number. 123 virtual bool Find(int number, ExtensionInfo* output) = 0; 124 }; 125 126 // Implementation of ExtensionFinder which finds extensions defined in .proto 127 // files which have been compiled into the binary. 128 class LIBPROTOBUF_EXPORT GeneratedExtensionFinder : public ExtensionFinder { 129 public: 130 GeneratedExtensionFinder(const MessageLite* containing_type) 131 : containing_type_(containing_type) {} 132 virtual ~GeneratedExtensionFinder() {} 133 134 // Returns true and fills in *output if found, otherwise returns false. 135 virtual bool Find(int number, ExtensionInfo* output); 136 137 private: 138 const MessageLite* containing_type_; 139 }; 140 141 // Note: extension_set_heavy.cc defines DescriptorPoolExtensionFinder for 142 // finding extensions from a DescriptorPool. 143 144 // This is an internal helper class intended for use within the protocol buffer 145 // library and generated classes. Clients should not use it directly. Instead, 146 // use the generated accessors such as GetExtension() of the class being 147 // extended. 148 // 149 // This class manages extensions for a protocol message object. The 150 // message's HasExtension(), GetExtension(), MutableExtension(), and 151 // ClearExtension() methods are just thin wrappers around the embedded 152 // ExtensionSet. When parsing, if a tag number is encountered which is 153 // inside one of the message type's extension ranges, the tag is passed 154 // off to the ExtensionSet for parsing. Etc. 155 class LIBPROTOBUF_EXPORT ExtensionSet { 156 public: 157 ExtensionSet(); 158 ~ExtensionSet(); 159 160 // These are called at startup by protocol-compiler-generated code to 161 // register known extensions. The registrations are used by ParseField() 162 // to look up extensions for parsed field numbers. Note that dynamic parsing 163 // does not use ParseField(); only protocol-compiler-generated parsing 164 // methods do. 165 static void RegisterExtension(const MessageLite* containing_type, 166 int number, FieldType type, 167 bool is_repeated, bool is_packed); 168 static void RegisterEnumExtension(const MessageLite* containing_type, 169 int number, FieldType type, 170 bool is_repeated, bool is_packed, 171 EnumValidityFunc* is_valid); 172 static void RegisterMessageExtension(const MessageLite* containing_type, 173 int number, FieldType type, 174 bool is_repeated, bool is_packed, 175 const MessageLite* prototype); 176 177 // ================================================================= 178 179 // Add all fields which are currently present to the given vector. This 180 // is useful to implement Reflection::ListFields(). 181 void AppendToList(const Descriptor* containing_type, 182 const DescriptorPool* pool, 183 vector<const FieldDescriptor*>* output) const; 184 185 // ================================================================= 186 // Accessors 187 // 188 // Generated message classes include type-safe templated wrappers around 189 // these methods. Generally you should use those rather than call these 190 // directly, unless you are doing low-level memory management. 191 // 192 // When calling any of these accessors, the extension number requested 193 // MUST exist in the DescriptorPool provided to the constructor. Otheriwse, 194 // the method will fail an assert. Normally, though, you would not call 195 // these directly; you would either call the generated accessors of your 196 // message class (e.g. GetExtension()) or you would call the accessors 197 // of the reflection interface. In both cases, it is impossible to 198 // trigger this assert failure: the generated accessors only accept 199 // linked-in extension types as parameters, while the Reflection interface 200 // requires you to provide the FieldDescriptor describing the extension. 201 // 202 // When calling any of these accessors, a protocol-compiler-generated 203 // implementation of the extension corresponding to the number MUST 204 // be linked in, and the FieldDescriptor used to refer to it MUST be 205 // the one generated by that linked-in code. Otherwise, the method will 206 // die on an assert failure. The message objects returned by the message 207 // accessors are guaranteed to be of the correct linked-in type. 208 // 209 // These methods pretty much match Reflection except that: 210 // - They're not virtual. 211 // - They identify fields by number rather than FieldDescriptors. 212 // - They identify enum values using integers rather than descriptors. 213 // - Strings provide Mutable() in addition to Set() accessors. 214 215 bool Has(int number) const; 216 int ExtensionSize(int number) const; // Size of a repeated extension. 217 int NumExtensions() const; // The number of extensions 218 FieldType ExtensionType(int number) const; 219 void ClearExtension(int number); 220 221 // singular fields ------------------------------------------------- 222 223 int32 GetInt32 (int number, int32 default_value) const; 224 int64 GetInt64 (int number, int64 default_value) const; 225 uint32 GetUInt32(int number, uint32 default_value) const; 226 uint64 GetUInt64(int number, uint64 default_value) const; 227 float GetFloat (int number, float default_value) const; 228 double GetDouble(int number, double default_value) const; 229 bool GetBool (int number, bool default_value) const; 230 int GetEnum (int number, int default_value) const; 231 const string & GetString (int number, const string& default_value) const; 232 const MessageLite& GetMessage(int number, 233 const MessageLite& default_value) const; 234 const MessageLite& GetMessage(int number, const Descriptor* message_type, 235 MessageFactory* factory) const; 236 237 // |descriptor| may be NULL so long as it is known that the descriptor for 238 // the extension lives in the same pool as the descriptor for the containing 239 // type. 240 #define desc const FieldDescriptor* descriptor // avoid line wrapping 241 void SetInt32 (int number, FieldType type, int32 value, desc); 242 void SetInt64 (int number, FieldType type, int64 value, desc); 243 void SetUInt32(int number, FieldType type, uint32 value, desc); 244 void SetUInt64(int number, FieldType type, uint64 value, desc); 245 void SetFloat (int number, FieldType type, float value, desc); 246 void SetDouble(int number, FieldType type, double value, desc); 247 void SetBool (int number, FieldType type, bool value, desc); 248 void SetEnum (int number, FieldType type, int value, desc); 249 void SetString(int number, FieldType type, const string& value, desc); 250 string * MutableString (int number, FieldType type, desc); 251 MessageLite* MutableMessage(int number, FieldType type, 252 const MessageLite& prototype, desc); 253 MessageLite* MutableMessage(const FieldDescriptor* decsriptor, 254 MessageFactory* factory); 255 // Adds the given message to the ExtensionSet, taking ownership of the 256 // message object. Existing message with the same number will be deleted. 257 // If "message" is NULL, this is equivalent to "ClearExtension(number)". 258 void SetAllocatedMessage(int number, FieldType type, 259 const FieldDescriptor* descriptor, 260 MessageLite* message); 261 MessageLite* ReleaseMessage(int number, const MessageLite& prototype); 262 MessageLite* ReleaseMessage(const FieldDescriptor* descriptor, 263 MessageFactory* factory); 264 #undef desc 265 266 // repeated fields ------------------------------------------------- 267 268 void* MutableRawRepeatedField(int number); 269 270 int32 GetRepeatedInt32 (int number, int index) const; 271 int64 GetRepeatedInt64 (int number, int index) const; 272 uint32 GetRepeatedUInt32(int number, int index) const; 273 uint64 GetRepeatedUInt64(int number, int index) const; 274 float GetRepeatedFloat (int number, int index) const; 275 double GetRepeatedDouble(int number, int index) const; 276 bool GetRepeatedBool (int number, int index) const; 277 int GetRepeatedEnum (int number, int index) const; 278 const string & GetRepeatedString (int number, int index) const; 279 const MessageLite& GetRepeatedMessage(int number, int index) const; 280 281 void SetRepeatedInt32 (int number, int index, int32 value); 282 void SetRepeatedInt64 (int number, int index, int64 value); 283 void SetRepeatedUInt32(int number, int index, uint32 value); 284 void SetRepeatedUInt64(int number, int index, uint64 value); 285 void SetRepeatedFloat (int number, int index, float value); 286 void SetRepeatedDouble(int number, int index, double value); 287 void SetRepeatedBool (int number, int index, bool value); 288 void SetRepeatedEnum (int number, int index, int value); 289 void SetRepeatedString(int number, int index, const string& value); 290 string * MutableRepeatedString (int number, int index); 291 MessageLite* MutableRepeatedMessage(int number, int index); 292 293 #define desc const FieldDescriptor* descriptor // avoid line wrapping 294 void AddInt32 (int number, FieldType type, bool packed, int32 value, desc); 295 void AddInt64 (int number, FieldType type, bool packed, int64 value, desc); 296 void AddUInt32(int number, FieldType type, bool packed, uint32 value, desc); 297 void AddUInt64(int number, FieldType type, bool packed, uint64 value, desc); 298 void AddFloat (int number, FieldType type, bool packed, float value, desc); 299 void AddDouble(int number, FieldType type, bool packed, double value, desc); 300 void AddBool (int number, FieldType type, bool packed, bool value, desc); 301 void AddEnum (int number, FieldType type, bool packed, int value, desc); 302 void AddString(int number, FieldType type, const string& value, desc); 303 string * AddString (int number, FieldType type, desc); 304 MessageLite* AddMessage(int number, FieldType type, 305 const MessageLite& prototype, desc); 306 MessageLite* AddMessage(const FieldDescriptor* descriptor, 307 MessageFactory* factory); 308 #undef desc 309 310 void RemoveLast(int number); 311 MessageLite* ReleaseLast(int number); 312 void SwapElements(int number, int index1, int index2); 313 314 // ----------------------------------------------------------------- 315 // TODO(kenton): Hardcore memory management accessors 316 317 // ================================================================= 318 // convenience methods for implementing methods of Message 319 // 320 // These could all be implemented in terms of the other methods of this 321 // class, but providing them here helps keep the generated code size down. 322 323 void Clear(); 324 void MergeFrom(const ExtensionSet& other); 325 void Swap(ExtensionSet* other); 326 bool IsInitialized() const; 327 328 // Parses a single extension from the input. The input should start out 329 // positioned immediately after the tag. 330 bool ParseField(uint32 tag, io::CodedInputStream* input, 331 ExtensionFinder* extension_finder, 332 FieldSkipper* field_skipper); 333 334 // Specific versions for lite or full messages (constructs the appropriate 335 // FieldSkipper automatically). |containing_type| is the default 336 // instance for the containing message; it is used only to look up the 337 // extension by number. See RegisterExtension(), above. Unlike the other 338 // methods of ExtensionSet, this only works for generated message types -- 339 // it looks up extensions registered using RegisterExtension(). 340 bool ParseField(uint32 tag, io::CodedInputStream* input, 341 const MessageLite* containing_type, 342 UnknownFieldSet* unknown_fields); 343 bool ParseFieldHeavy(uint32 tag, io::CodedInputStream* input, 344 const Message* containing_type, 345 UnknownFieldSet* unknown_fields); 346 347 // Parse an entire message in MessageSet format. Such messages have no 348 // fields, only extensions. 349 bool ParseMessageSet(io::CodedInputStream* input, 350 ExtensionFinder* extension_finder, 351 FieldSkipper* field_skipper); 352 353 // Specific versions for lite or full messages (constructs the appropriate 354 // FieldSkipper automatically). 355 bool ParseMessageSet(io::CodedInputStream* input, 356 const MessageLite* containing_type, 357 UnknownFieldSet* unknown_fields); 358 bool ParseMessageSetHeavy(io::CodedInputStream* input, 359 const Message* containing_type, 360 UnknownFieldSet* unknown_fields); 361 362 // Write all extension fields with field numbers in the range 363 // [start_field_number, end_field_number) 364 // to the output stream, using the cached sizes computed when ByteSize() was 365 // last called. Note that the range bounds are inclusive-exclusive. 366 void SerializeWithCachedSizes(int start_field_number, 367 int end_field_number, 368 io::CodedOutputStream* output) const; 369 370 // Same as SerializeWithCachedSizes, but without any bounds checking. 371 // The caller must ensure that target has sufficient capacity for the 372 // serialized extensions. 373 // 374 // Returns a pointer past the last written byte. 375 uint8* SerializeWithCachedSizesToArray(int start_field_number, 376 int end_field_number, 377 uint8* target) const; 378 379 // Like above but serializes in MessageSet format. 380 void SerializeMessageSetWithCachedSizes(io::CodedOutputStream* output) const; 381 uint8* SerializeMessageSetWithCachedSizesToArray(uint8* target) const; 382 383 // Returns the total serialized size of all the extensions. 384 int ByteSize() const; 385 386 // Like ByteSize() but uses MessageSet format. 387 int MessageSetByteSize() const; 388 389 // Returns (an estimate of) the total number of bytes used for storing the 390 // extensions in memory, excluding sizeof(*this). If the ExtensionSet is 391 // for a lite message (and thus possibly contains lite messages), the results 392 // are undefined (might work, might crash, might corrupt data, might not even 393 // be linked in). It's up to the protocol compiler to avoid calling this on 394 // such ExtensionSets (easy enough since lite messages don't implement 395 // SpaceUsed()). 396 int SpaceUsedExcludingSelf() const; 397 398 private: 399 400 // Interface of a lazily parsed singular message extension. 401 class LIBPROTOBUF_EXPORT LazyMessageExtension { 402 public: 403 LazyMessageExtension() {} 404 virtual ~LazyMessageExtension() {} 405 406 virtual LazyMessageExtension* New() const = 0; 407 virtual const MessageLite& GetMessage( 408 const MessageLite& prototype) const = 0; 409 virtual MessageLite* MutableMessage(const MessageLite& prototype) = 0; 410 virtual void SetAllocatedMessage(MessageLite *message) = 0; 411 virtual MessageLite* ReleaseMessage(const MessageLite& prototype) = 0; 412 413 virtual bool IsInitialized() const = 0; 414 virtual int ByteSize() const = 0; 415 virtual int SpaceUsed() const = 0; 416 417 virtual void MergeFrom(const LazyMessageExtension& other) = 0; 418 virtual void Clear() = 0; 419 420 virtual bool ReadMessage(const MessageLite& prototype, 421 io::CodedInputStream* input) = 0; 422 virtual void WriteMessage(int number, 423 io::CodedOutputStream* output) const = 0; 424 virtual uint8* WriteMessageToArray(int number, uint8* target) const = 0; 425 private: 426 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(LazyMessageExtension); 427 }; 428 struct Extension { 429 // The order of these fields packs Extension into 24 bytes when using 8 430 // byte alignment. Consider this when adding or removing fields here. 431 union { 432 int32 int32_value; 433 int64 int64_value; 434 uint32 uint32_value; 435 uint64 uint64_value; 436 float float_value; 437 double double_value; 438 bool bool_value; 439 int enum_value; 440 string* string_value; 441 MessageLite* message_value; 442 LazyMessageExtension* lazymessage_value; 443 444 RepeatedField <int32 >* repeated_int32_value; 445 RepeatedField <int64 >* repeated_int64_value; 446 RepeatedField <uint32 >* repeated_uint32_value; 447 RepeatedField <uint64 >* repeated_uint64_value; 448 RepeatedField <float >* repeated_float_value; 449 RepeatedField <double >* repeated_double_value; 450 RepeatedField <bool >* repeated_bool_value; 451 RepeatedField <int >* repeated_enum_value; 452 RepeatedPtrField<string >* repeated_string_value; 453 RepeatedPtrField<MessageLite>* repeated_message_value; 454 }; 455 456 FieldType type; 457 bool is_repeated; 458 459 // For singular types, indicates if the extension is "cleared". This 460 // happens when an extension is set and then later cleared by the caller. 461 // We want to keep the Extension object around for reuse, so instead of 462 // removing it from the map, we just set is_cleared = true. This has no 463 // meaning for repeated types; for those, the size of the RepeatedField 464 // simply becomes zero when cleared. 465 bool is_cleared : 4; 466 467 // For singular message types, indicates whether lazy parsing is enabled 468 // for this extension. This field is only valid when type == TYPE_MESSAGE 469 // and !is_repeated because we only support lazy parsing for singular 470 // message types currently. If is_lazy = true, the extension is stored in 471 // lazymessage_value. Otherwise, the extension will be message_value. 472 bool is_lazy : 4; 473 474 // For repeated types, this indicates if the [packed=true] option is set. 475 bool is_packed; 476 477 // For packed fields, the size of the packed data is recorded here when 478 // ByteSize() is called then used during serialization. 479 // TODO(kenton): Use atomic<int> when C++ supports it. 480 mutable int cached_size; 481 482 // The descriptor for this extension, if one exists and is known. May be 483 // NULL. Must not be NULL if the descriptor for the extension does not 484 // live in the same pool as the descriptor for the containing type. 485 const FieldDescriptor* descriptor; 486 487 // Some helper methods for operations on a single Extension. 488 void SerializeFieldWithCachedSizes( 489 int number, 490 io::CodedOutputStream* output) const; 491 uint8* SerializeFieldWithCachedSizesToArray( 492 int number, 493 uint8* target) const; 494 void SerializeMessageSetItemWithCachedSizes( 495 int number, 496 io::CodedOutputStream* output) const; 497 uint8* SerializeMessageSetItemWithCachedSizesToArray( 498 int number, 499 uint8* target) const; 500 int ByteSize(int number) const; 501 int MessageSetItemByteSize(int number) const; 502 void Clear(); 503 int GetSize() const; 504 void Free(); 505 int SpaceUsedExcludingSelf() const; 506 }; 507 508 509 // Returns true and fills field_number and extension if extension is found. 510 bool FindExtensionInfoFromTag(uint32 tag, ExtensionFinder* extension_finder, 511 int* field_number, ExtensionInfo* extension); 512 513 // Parses a single extension from the input. The input should start out 514 // positioned immediately after the wire tag. This method is called in 515 // ParseField() after field number is extracted from the wire tag and 516 // ExtensionInfo is found by the field number. 517 bool ParseFieldWithExtensionInfo(int field_number, 518 const ExtensionInfo& extension, 519 io::CodedInputStream* input, 520 FieldSkipper* field_skipper); 521 522 // Like ParseField(), but this method may parse singular message extensions 523 // lazily depending on the value of FLAGS_eagerly_parse_message_sets. 524 bool ParseFieldMaybeLazily(uint32 tag, io::CodedInputStream* input, 525 ExtensionFinder* extension_finder, 526 FieldSkipper* field_skipper); 527 528 // Gets the extension with the given number, creating it if it does not 529 // already exist. Returns true if the extension did not already exist. 530 bool MaybeNewExtension(int number, const FieldDescriptor* descriptor, 531 Extension** result); 532 533 // Parse a single MessageSet item -- called just after the item group start 534 // tag has been read. 535 bool ParseMessageSetItem(io::CodedInputStream* input, 536 ExtensionFinder* extension_finder, 537 FieldSkipper* field_skipper); 538 539 540 // Hack: RepeatedPtrFieldBase declares ExtensionSet as a friend. This 541 // friendship should automatically extend to ExtensionSet::Extension, but 542 // unfortunately some older compilers (e.g. GCC 3.4.4) do not implement this 543 // correctly. So, we must provide helpers for calling methods of that 544 // class. 545 546 // Defined in extension_set_heavy.cc. 547 static inline int RepeatedMessage_SpaceUsedExcludingSelf( 548 RepeatedPtrFieldBase* field); 549 550 // The Extension struct is small enough to be passed by value, so we use it 551 // directly as the value type in the map rather than use pointers. We use 552 // a map rather than hash_map here because we expect most ExtensionSets will 553 // only contain a small number of extensions whereas hash_map is optimized 554 // for 100 elements or more. Also, we want AppendToList() to order fields 555 // by field number. 556 std::map<int, Extension> extensions_; 557 558 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ExtensionSet); 559 }; 560 561 // These are just for convenience... 562 inline void ExtensionSet::SetString(int number, FieldType type, 563 const string& value, 564 const FieldDescriptor* descriptor) { 565 MutableString(number, type, descriptor)->assign(value); 566 } 567 inline void ExtensionSet::SetRepeatedString(int number, int index, 568 const string& value) { 569 MutableRepeatedString(number, index)->assign(value); 570 } 571 inline void ExtensionSet::AddString(int number, FieldType type, 572 const string& value, 573 const FieldDescriptor* descriptor) { 574 AddString(number, type, descriptor)->assign(value); 575 } 576 577 // =================================================================== 578 // Glue for generated extension accessors 579 580 // ------------------------------------------------------------------- 581 // Template magic 582 583 // First we have a set of classes representing "type traits" for different 584 // field types. A type traits class knows how to implement basic accessors 585 // for extensions of a particular type given an ExtensionSet. The signature 586 // for a type traits class looks like this: 587 // 588 // class TypeTraits { 589 // public: 590 // typedef ? ConstType; 591 // typedef ? MutableType; 592 // 593 // static inline ConstType Get(int number, const ExtensionSet& set); 594 // static inline void Set(int number, ConstType value, ExtensionSet* set); 595 // static inline MutableType Mutable(int number, ExtensionSet* set); 596 // 597 // // Variants for repeated fields. 598 // static inline ConstType Get(int number, const ExtensionSet& set, 599 // int index); 600 // static inline void Set(int number, int index, 601 // ConstType value, ExtensionSet* set); 602 // static inline MutableType Mutable(int number, int index, 603 // ExtensionSet* set); 604 // static inline void Add(int number, ConstType value, ExtensionSet* set); 605 // static inline MutableType Add(int number, ExtensionSet* set); 606 // }; 607 // 608 // Not all of these methods make sense for all field types. For example, the 609 // "Mutable" methods only make sense for strings and messages, and the 610 // repeated methods only make sense for repeated types. So, each type 611 // traits class implements only the set of methods from this signature that it 612 // actually supports. This will cause a compiler error if the user tries to 613 // access an extension using a method that doesn't make sense for its type. 614 // For example, if "foo" is an extension of type "optional int32", then if you 615 // try to write code like: 616 // my_message.MutableExtension(foo) 617 // you will get a compile error because PrimitiveTypeTraits<int32> does not 618 // have a "Mutable()" method. 619 620 // ------------------------------------------------------------------- 621 // PrimitiveTypeTraits 622 623 // Since the ExtensionSet has different methods for each primitive type, 624 // we must explicitly define the methods of the type traits class for each 625 // known type. 626 template <typename Type> 627 class PrimitiveTypeTraits { 628 public: 629 typedef Type ConstType; 630 631 static inline ConstType Get(int number, const ExtensionSet& set, 632 ConstType default_value); 633 static inline void Set(int number, FieldType field_type, 634 ConstType value, ExtensionSet* set); 635 }; 636 637 template <typename Type> 638 class RepeatedPrimitiveTypeTraits { 639 public: 640 typedef Type ConstType; 641 642 static inline Type Get(int number, const ExtensionSet& set, int index); 643 static inline void Set(int number, int index, Type value, ExtensionSet* set); 644 static inline void Add(int number, FieldType field_type, 645 bool is_packed, Type value, ExtensionSet* set); 646 }; 647 648 #define PROTOBUF_DEFINE_PRIMITIVE_TYPE(TYPE, METHOD) \ 649 template<> inline TYPE PrimitiveTypeTraits<TYPE>::Get( \ 650 int number, const ExtensionSet& set, TYPE default_value) { \ 651 return set.Get##METHOD(number, default_value); \ 652 } \ 653 template<> inline void PrimitiveTypeTraits<TYPE>::Set( \ 654 int number, FieldType field_type, TYPE value, ExtensionSet* set) { \ 655 set->Set##METHOD(number, field_type, value, NULL); \ 656 } \ 657 \ 658 template<> inline TYPE RepeatedPrimitiveTypeTraits<TYPE>::Get( \ 659 int number, const ExtensionSet& set, int index) { \ 660 return set.GetRepeated##METHOD(number, index); \ 661 } \ 662 template<> inline void RepeatedPrimitiveTypeTraits<TYPE>::Set( \ 663 int number, int index, TYPE value, ExtensionSet* set) { \ 664 set->SetRepeated##METHOD(number, index, value); \ 665 } \ 666 template<> inline void RepeatedPrimitiveTypeTraits<TYPE>::Add( \ 667 int number, FieldType field_type, bool is_packed, \ 668 TYPE value, ExtensionSet* set) { \ 669 set->Add##METHOD(number, field_type, is_packed, value, NULL); \ 670 } 671 672 PROTOBUF_DEFINE_PRIMITIVE_TYPE( int32, Int32) 673 PROTOBUF_DEFINE_PRIMITIVE_TYPE( int64, Int64) 674 PROTOBUF_DEFINE_PRIMITIVE_TYPE(uint32, UInt32) 675 PROTOBUF_DEFINE_PRIMITIVE_TYPE(uint64, UInt64) 676 PROTOBUF_DEFINE_PRIMITIVE_TYPE( float, Float) 677 PROTOBUF_DEFINE_PRIMITIVE_TYPE(double, Double) 678 PROTOBUF_DEFINE_PRIMITIVE_TYPE( bool, Bool) 679 680 #undef PROTOBUF_DEFINE_PRIMITIVE_TYPE 681 682 // ------------------------------------------------------------------- 683 // StringTypeTraits 684 685 // Strings support both Set() and Mutable(). 686 class LIBPROTOBUF_EXPORT StringTypeTraits { 687 public: 688 typedef const string& ConstType; 689 typedef string* MutableType; 690 691 static inline const string& Get(int number, const ExtensionSet& set, 692 ConstType default_value) { 693 return set.GetString(number, default_value); 694 } 695 static inline void Set(int number, FieldType field_type, 696 const string& value, ExtensionSet* set) { 697 set->SetString(number, field_type, value, NULL); 698 } 699 static inline string* Mutable(int number, FieldType field_type, 700 ExtensionSet* set) { 701 return set->MutableString(number, field_type, NULL); 702 } 703 }; 704 705 class LIBPROTOBUF_EXPORT RepeatedStringTypeTraits { 706 public: 707 typedef const string& ConstType; 708 typedef string* MutableType; 709 710 static inline const string& Get(int number, const ExtensionSet& set, 711 int index) { 712 return set.GetRepeatedString(number, index); 713 } 714 static inline void Set(int number, int index, 715 const string& value, ExtensionSet* set) { 716 set->SetRepeatedString(number, index, value); 717 } 718 static inline string* Mutable(int number, int index, ExtensionSet* set) { 719 return set->MutableRepeatedString(number, index); 720 } 721 static inline void Add(int number, FieldType field_type, 722 bool /*is_packed*/, const string& value, 723 ExtensionSet* set) { 724 set->AddString(number, field_type, value, NULL); 725 } 726 static inline string* Add(int number, FieldType field_type, 727 ExtensionSet* set) { 728 return set->AddString(number, field_type, NULL); 729 } 730 }; 731 732 // ------------------------------------------------------------------- 733 // EnumTypeTraits 734 735 // ExtensionSet represents enums using integers internally, so we have to 736 // static_cast around. 737 template <typename Type, bool IsValid(int)> 738 class EnumTypeTraits { 739 public: 740 typedef Type ConstType; 741 742 static inline ConstType Get(int number, const ExtensionSet& set, 743 ConstType default_value) { 744 return static_cast<Type>(set.GetEnum(number, default_value)); 745 } 746 static inline void Set(int number, FieldType field_type, 747 ConstType value, ExtensionSet* set) { 748 GOOGLE_DCHECK(IsValid(value)); 749 set->SetEnum(number, field_type, value, NULL); 750 } 751 }; 752 753 template <typename Type, bool IsValid(int)> 754 class RepeatedEnumTypeTraits { 755 public: 756 typedef Type ConstType; 757 758 static inline ConstType Get(int number, const ExtensionSet& set, int index) { 759 return static_cast<Type>(set.GetRepeatedEnum(number, index)); 760 } 761 static inline void Set(int number, int index, 762 ConstType value, ExtensionSet* set) { 763 GOOGLE_DCHECK(IsValid(value)); 764 set->SetRepeatedEnum(number, index, value); 765 } 766 static inline void Add(int number, FieldType field_type, 767 bool is_packed, ConstType value, ExtensionSet* set) { 768 GOOGLE_DCHECK(IsValid(value)); 769 set->AddEnum(number, field_type, is_packed, value, NULL); 770 } 771 }; 772 773 // ------------------------------------------------------------------- 774 // MessageTypeTraits 775 776 // ExtensionSet guarantees that when manipulating extensions with message 777 // types, the implementation used will be the compiled-in class representing 778 // that type. So, we can static_cast down to the exact type we expect. 779 template <typename Type> 780 class MessageTypeTraits { 781 public: 782 typedef const Type& ConstType; 783 typedef Type* MutableType; 784 785 static inline ConstType Get(int number, const ExtensionSet& set, 786 ConstType default_value) { 787 return static_cast<const Type&>( 788 set.GetMessage(number, default_value)); 789 } 790 static inline MutableType Mutable(int number, FieldType field_type, 791 ExtensionSet* set) { 792 return static_cast<Type*>( 793 set->MutableMessage(number, field_type, Type::default_instance(), NULL)); 794 } 795 static inline void SetAllocated(int number, FieldType field_type, 796 MutableType message, ExtensionSet* set) { 797 set->SetAllocatedMessage(number, field_type, NULL, message); 798 } 799 static inline MutableType Release(int number, FieldType field_type, 800 ExtensionSet* set) { 801 return static_cast<Type*>(set->ReleaseMessage( 802 number, Type::default_instance())); 803 } 804 }; 805 806 template <typename Type> 807 class RepeatedMessageTypeTraits { 808 public: 809 typedef const Type& ConstType; 810 typedef Type* MutableType; 811 812 static inline ConstType Get(int number, const ExtensionSet& set, int index) { 813 return static_cast<const Type&>(set.GetRepeatedMessage(number, index)); 814 } 815 static inline MutableType Mutable(int number, int index, ExtensionSet* set) { 816 return static_cast<Type*>(set->MutableRepeatedMessage(number, index)); 817 } 818 static inline MutableType Add(int number, FieldType field_type, 819 ExtensionSet* set) { 820 return static_cast<Type*>( 821 set->AddMessage(number, field_type, Type::default_instance(), NULL)); 822 } 823 }; 824 825 // ------------------------------------------------------------------- 826 // ExtensionIdentifier 827 828 // This is the type of actual extension objects. E.g. if you have: 829 // extends Foo with optional int32 bar = 1234; 830 // then "bar" will be defined in C++ as: 831 // ExtensionIdentifier<Foo, PrimitiveTypeTraits<int32>, 1, false> bar(1234); 832 // 833 // Note that we could, in theory, supply the field number as a template 834 // parameter, and thus make an instance of ExtensionIdentifier have no 835 // actual contents. However, if we did that, then using at extension 836 // identifier would not necessarily cause the compiler to output any sort 837 // of reference to any simple defined in the extension's .pb.o file. Some 838 // linkers will actually drop object files that are not explicitly referenced, 839 // but that would be bad because it would cause this extension to not be 840 // registered at static initialization, and therefore using it would crash. 841 842 template <typename ExtendeeType, typename TypeTraitsType, 843 FieldType field_type, bool is_packed> 844 class ExtensionIdentifier { 845 public: 846 typedef TypeTraitsType TypeTraits; 847 typedef ExtendeeType Extendee; 848 849 ExtensionIdentifier(int number, typename TypeTraits::ConstType default_value) 850 : number_(number), default_value_(default_value) {} 851 inline int number() const { return number_; } 852 typename TypeTraits::ConstType default_value() const { 853 return default_value_; 854 } 855 856 private: 857 const int number_; 858 typename TypeTraits::ConstType default_value_; 859 }; 860 861 // ------------------------------------------------------------------- 862 // Generated accessors 863 864 // This macro should be expanded in the context of a generated type which 865 // has extensions. 866 // 867 // We use "_proto_TypeTraits" as a type name below because "TypeTraits" 868 // causes problems if the class has a nested message or enum type with that 869 // name and "_TypeTraits" is technically reserved for the C++ library since 870 // it starts with an underscore followed by a capital letter. 871 // 872 // For similar reason, we use "_field_type" and "_is_packed" as parameter names 873 // below, so that "field_type" and "is_packed" can be used as field names. 874 #define GOOGLE_PROTOBUF_EXTENSION_ACCESSORS(CLASSNAME) \ 875 /* Has, Size, Clear */ \ 876 template <typename _proto_TypeTraits, \ 877 ::google::protobuf::internal::FieldType _field_type, \ 878 bool _is_packed> \ 879 inline bool HasExtension( \ 880 const ::google::protobuf::internal::ExtensionIdentifier< \ 881 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) const { \ 882 return _extensions_.Has(id.number()); \ 883 } \ 884 \ 885 template <typename _proto_TypeTraits, \ 886 ::google::protobuf::internal::FieldType _field_type, \ 887 bool _is_packed> \ 888 inline void ClearExtension( \ 889 const ::google::protobuf::internal::ExtensionIdentifier< \ 890 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) { \ 891 _extensions_.ClearExtension(id.number()); \ 892 } \ 893 \ 894 template <typename _proto_TypeTraits, \ 895 ::google::protobuf::internal::FieldType _field_type, \ 896 bool _is_packed> \ 897 inline int ExtensionSize( \ 898 const ::google::protobuf::internal::ExtensionIdentifier< \ 899 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) const { \ 900 return _extensions_.ExtensionSize(id.number()); \ 901 } \ 902 \ 903 /* Singular accessors */ \ 904 template <typename _proto_TypeTraits, \ 905 ::google::protobuf::internal::FieldType _field_type, \ 906 bool _is_packed> \ 907 inline typename _proto_TypeTraits::ConstType GetExtension( \ 908 const ::google::protobuf::internal::ExtensionIdentifier< \ 909 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) const { \ 910 return _proto_TypeTraits::Get(id.number(), _extensions_, \ 911 id.default_value()); \ 912 } \ 913 \ 914 template <typename _proto_TypeTraits, \ 915 ::google::protobuf::internal::FieldType _field_type, \ 916 bool _is_packed> \ 917 inline typename _proto_TypeTraits::MutableType MutableExtension( \ 918 const ::google::protobuf::internal::ExtensionIdentifier< \ 919 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) { \ 920 return _proto_TypeTraits::Mutable(id.number(), _field_type, \ 921 &_extensions_); \ 922 } \ 923 \ 924 template <typename _proto_TypeTraits, \ 925 ::google::protobuf::internal::FieldType _field_type, \ 926 bool _is_packed> \ 927 inline void SetExtension( \ 928 const ::google::protobuf::internal::ExtensionIdentifier< \ 929 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 930 typename _proto_TypeTraits::ConstType value) { \ 931 _proto_TypeTraits::Set(id.number(), _field_type, value, &_extensions_); \ 932 } \ 933 \ 934 template <typename _proto_TypeTraits, \ 935 ::google::protobuf::internal::FieldType _field_type, \ 936 bool _is_packed> \ 937 inline void SetAllocatedExtension( \ 938 const ::google::protobuf::internal::ExtensionIdentifier< \ 939 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 940 typename _proto_TypeTraits::MutableType value) { \ 941 _proto_TypeTraits::SetAllocated(id.number(), _field_type, \ 942 value, &_extensions_); \ 943 } \ 944 template <typename _proto_TypeTraits, \ 945 ::google::protobuf::internal::FieldType _field_type, \ 946 bool _is_packed> \ 947 inline typename _proto_TypeTraits::MutableType ReleaseExtension( \ 948 const ::google::protobuf::internal::ExtensionIdentifier< \ 949 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) { \ 950 return _proto_TypeTraits::Release(id.number(), _field_type, \ 951 &_extensions_); \ 952 } \ 953 \ 954 /* Repeated accessors */ \ 955 template <typename _proto_TypeTraits, \ 956 ::google::protobuf::internal::FieldType _field_type, \ 957 bool _is_packed> \ 958 inline typename _proto_TypeTraits::ConstType GetExtension( \ 959 const ::google::protobuf::internal::ExtensionIdentifier< \ 960 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 961 int index) const { \ 962 return _proto_TypeTraits::Get(id.number(), _extensions_, index); \ 963 } \ 964 \ 965 template <typename _proto_TypeTraits, \ 966 ::google::protobuf::internal::FieldType _field_type, \ 967 bool _is_packed> \ 968 inline typename _proto_TypeTraits::MutableType MutableExtension( \ 969 const ::google::protobuf::internal::ExtensionIdentifier< \ 970 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 971 int index) { \ 972 return _proto_TypeTraits::Mutable(id.number(), index, &_extensions_); \ 973 } \ 974 \ 975 template <typename _proto_TypeTraits, \ 976 ::google::protobuf::internal::FieldType _field_type, \ 977 bool _is_packed> \ 978 inline void SetExtension( \ 979 const ::google::protobuf::internal::ExtensionIdentifier< \ 980 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 981 int index, typename _proto_TypeTraits::ConstType value) { \ 982 _proto_TypeTraits::Set(id.number(), index, value, &_extensions_); \ 983 } \ 984 \ 985 template <typename _proto_TypeTraits, \ 986 ::google::protobuf::internal::FieldType _field_type, \ 987 bool _is_packed> \ 988 inline typename _proto_TypeTraits::MutableType AddExtension( \ 989 const ::google::protobuf::internal::ExtensionIdentifier< \ 990 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id) { \ 991 return _proto_TypeTraits::Add(id.number(), _field_type, &_extensions_); \ 992 } \ 993 \ 994 template <typename _proto_TypeTraits, \ 995 ::google::protobuf::internal::FieldType _field_type, \ 996 bool _is_packed> \ 997 inline void AddExtension( \ 998 const ::google::protobuf::internal::ExtensionIdentifier< \ 999 CLASSNAME, _proto_TypeTraits, _field_type, _is_packed>& id, \ 1000 typename _proto_TypeTraits::ConstType value) { \ 1001 _proto_TypeTraits::Add(id.number(), _field_type, _is_packed, \ 1002 value, &_extensions_); \ 1003 } 1004 1005 } // namespace internal 1006 } // namespace protobuf 1007 1008 } // namespace google 1009 #endif // GOOGLE_PROTOBUF_EXTENSION_SET_H__ 1010
