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: [email protected] (Kenton Varda)
32// Based on original Protocol Buffers design by
33// Sanjay Ghemawat, Jeff Dean, and others.
34//
35// Defines Message, the abstract interface implemented by non-lite
36// protocol message objects. Although it's possible to implement this
37// interface manually, most users will use the protocol compiler to
38// generate implementations.
39//
40// Example usage:
41//
42// Say you have a message defined as:
43//
44// message Foo {
45// optional string text = 1;
46// repeated int32 numbers = 2;
47// }
48//
49// Then, if you used the protocol compiler to generate a class from the above
50// definition, you could use it like so:
51//
52// std::string data; // Will store a serialized version of the message.
53//
54// {
55// // Create a message and serialize it.
56// Foo foo;
57// foo.set_text("Hello World!");
58// foo.add_numbers(1);
59// foo.add_numbers(5);
60// foo.add_numbers(42);
61//
62// foo.SerializeToString(&data);
63// }
64//
65// {
66// // Parse the serialized message and check that it contains the
67// // correct data.
68// Foo foo;
69// foo.ParseFromString(data);
70//
71// assert(foo.text() == "Hello World!");
72// assert(foo.numbers_size() == 3);
73// assert(foo.numbers(0) == 1);
74// assert(foo.numbers(1) == 5);
75// assert(foo.numbers(2) == 42);
76// }
77//
78// {
79// // Same as the last block, but do it dynamically via the Message
80// // reflection interface.
81// Message* foo = new Foo;
82// const Descriptor* descriptor = foo->GetDescriptor();
83//
84// // Get the descriptors for the fields we're interested in and verify
85// // their types.
86// const FieldDescriptor* text_field = descriptor->FindFieldByName("text");
87// assert(text_field != nullptr);
88// assert(text_field->type() == FieldDescriptor::TYPE_STRING);
89// assert(text_field->label() == FieldDescriptor::LABEL_OPTIONAL);
90// const FieldDescriptor* numbers_field = descriptor->
91// FindFieldByName("numbers");
92// assert(numbers_field != nullptr);
93// assert(numbers_field->type() == FieldDescriptor::TYPE_INT32);
94// assert(numbers_field->label() == FieldDescriptor::LABEL_REPEATED);
95//
96// // Parse the message.
97// foo->ParseFromString(data);
98//
99// // Use the reflection interface to examine the contents.
100// const Reflection* reflection = foo->GetReflection();
101// assert(reflection->GetString(*foo, text_field) == "Hello World!");
102// assert(reflection->FieldSize(*foo, numbers_field) == 3);
103// assert(reflection->GetRepeatedInt32(*foo, numbers_field, 0) == 1);
104// assert(reflection->GetRepeatedInt32(*foo, numbers_field, 1) == 5);
105// assert(reflection->GetRepeatedInt32(*foo, numbers_field, 2) == 42);
106//
107// delete foo;
108// }
109
110#ifndef GOOGLE_PROTOBUF_MESSAGE_H__
111#define GOOGLE_PROTOBUF_MESSAGE_H__
112
113#include <iosfwd>
114#include <string>
115#include <type_traits>
116#include <vector>
117
118#include <google/protobuf/stubs/casts.h>
119#include <google/protobuf/stubs/common.h>
120#include <google/protobuf/arena.h>
121#include <google/protobuf/descriptor.h>
122#include <google/protobuf/generated_message_reflection.h>
123#include <google/protobuf/message_lite.h>
124#include <google/protobuf/port.h>
125
126
127#define GOOGLE_PROTOBUF_HAS_ONEOF
128#define GOOGLE_PROTOBUF_HAS_ARENAS
129
130#include <google/protobuf/port_def.inc>
131
132#ifdef SWIG
133#error "You cannot SWIG proto headers"
134#endif
135
136namespace google {
137namespace protobuf {
138
139// Defined in this file.
140class Message;
141class Reflection;
142class MessageFactory;
143
144// Defined in other files.
145class AssignDescriptorsHelper;
146class DynamicMessageFactory;
147class MapKey;
148class MapValueRef;
149class MapIterator;
150class MapReflectionTester;
151
152namespace internal {
153struct DescriptorTable;
154class MapFieldBase;
155}
156class UnknownFieldSet; // unknown_field_set.h
157namespace io {
158class ZeroCopyInputStream; // zero_copy_stream.h
159class ZeroCopyOutputStream; // zero_copy_stream.h
160class CodedInputStream; // coded_stream.h
161class CodedOutputStream; // coded_stream.h
162} // namespace io
163namespace python {
164class MapReflectionFriend; // scalar_map_container.h
165}
166namespace expr {
167class CelMapReflectionFriend; // field_backed_map_impl.cc
168}
169
170namespace internal {
171class MapFieldPrinterHelper; // text_format.cc
172}
173
174
175namespace internal {
176class ReflectionAccessor; // message.cc
177class ReflectionOps; // reflection_ops.h
178class MapKeySorter; // wire_format.cc
179class WireFormat; // wire_format.h
180class MapFieldReflectionTest; // map_test.cc
181} // namespace internal
182
183template <typename T>
184class RepeatedField; // repeated_field.h
185
186template <typename T>
187class RepeatedPtrField; // repeated_field.h
188
189// A container to hold message metadata.
190struct Metadata {
191 const Descriptor* descriptor;
192 const Reflection* reflection;
193};
194
195// Abstract interface for protocol messages.
196//
197// See also MessageLite, which contains most every-day operations. Message
198// adds descriptors and reflection on top of that.
199//
200// The methods of this class that are virtual but not pure-virtual have
201// default implementations based on reflection. Message classes which are
202// optimized for speed will want to override these with faster implementations,
203// but classes optimized for code size may be happy with keeping them. See
204// the optimize_for option in descriptor.proto.
205class PROTOBUF_EXPORT Message : public MessageLite {
206 public:
207 inline Message() {}
208 ~Message() override {}
209
210 // Basic Operations ------------------------------------------------
211
212 // Construct a new instance of the same type. Ownership is passed to the
213 // caller. (This is also defined in MessageLite, but is defined again here
214 // for return-type covariance.)
215 Message* New() const override = 0;
216
217 // Construct a new instance on the arena. Ownership is passed to the caller
218 // if arena is a nullptr. Default implementation allows for API compatibility
219 // during the Arena transition.
220 Message* New(Arena* arena) const override {
221 Message* message = New();
222 if (arena != nullptr) {
223 arena->Own(message);
224 }
225 return message;
226 }
227
228 // Make this message into a copy of the given message. The given message
229 // must have the same descriptor, but need not necessarily be the same class.
230 // By default this is just implemented as "Clear(); MergeFrom(from);".
231 virtual void CopyFrom(const Message& from);
232
233 // Merge the fields from the given message into this message. Singular
234 // fields will be overwritten, if specified in from, except for embedded
235 // messages which will be merged. Repeated fields will be concatenated.
236 // The given message must be of the same type as this message (i.e. the
237 // exact same class).
238 virtual void MergeFrom(const Message& from);
239
240 // Verifies that IsInitialized() returns true. GOOGLE_CHECK-fails otherwise, with
241 // a nice error message.
242 void CheckInitialized() const;
243
244 // Slowly build a list of all required fields that are not set.
245 // This is much, much slower than IsInitialized() as it is implemented
246 // purely via reflection. Generally, you should not call this unless you
247 // have already determined that an error exists by calling IsInitialized().
248 void FindInitializationErrors(std::vector<std::string>* errors) const;
249
250 // Like FindInitializationErrors, but joins all the strings, delimited by
251 // commas, and returns them.
252 std::string InitializationErrorString() const override;
253
254 // Clears all unknown fields from this message and all embedded messages.
255 // Normally, if unknown tag numbers are encountered when parsing a message,
256 // the tag and value are stored in the message's UnknownFieldSet and
257 // then written back out when the message is serialized. This allows servers
258 // which simply route messages to other servers to pass through messages
259 // that have new field definitions which they don't yet know about. However,
260 // this behavior can have security implications. To avoid it, call this
261 // method after parsing.
262 //
263 // See Reflection::GetUnknownFields() for more on unknown fields.
264 virtual void DiscardUnknownFields();
265
266 // Computes (an estimate of) the total number of bytes currently used for
267 // storing the message in memory. The default implementation calls the
268 // Reflection object's SpaceUsed() method.
269 //
270 // SpaceUsed() is noticeably slower than ByteSize(), as it is implemented
271 // using reflection (rather than the generated code implementation for
272 // ByteSize()). Like ByteSize(), its CPU time is linear in the number of
273 // fields defined for the proto.
274 virtual size_t SpaceUsedLong() const;
275
276 PROTOBUF_DEPRECATED_MSG("Please use SpaceUsedLong() instead")
277 int SpaceUsed() const { return internal::ToIntSize(SpaceUsedLong()); }
278
279 // Debugging & Testing----------------------------------------------
280
281 // Generates a human readable form of this message, useful for debugging
282 // and other purposes.
283 std::string DebugString() const;
284 // Like DebugString(), but with less whitespace.
285 std::string ShortDebugString() const;
286 // Like DebugString(), but do not escape UTF-8 byte sequences.
287 std::string Utf8DebugString() const;
288 // Convenience function useful in GDB. Prints DebugString() to stdout.
289 void PrintDebugString() const;
290
291 // Reflection-based methods ----------------------------------------
292 // These methods are pure-virtual in MessageLite, but Message provides
293 // reflection-based default implementations.
294
295 std::string GetTypeName() const override;
296 void Clear() override;
297 bool IsInitialized() const override;
298 void CheckTypeAndMergeFrom(const MessageLite& other) override;
299#if GOOGLE_PROTOBUF_ENABLE_EXPERIMENTAL_PARSER
300 // Reflective parser
301 const char* _InternalParse(const char* ptr,
302 internal::ParseContext* ctx) override;
303#else
304 bool MergePartialFromCodedStream(io::CodedInputStream* input) override;
305#endif
306 size_t ByteSizeLong() const override;
307 void SerializeWithCachedSizes(io::CodedOutputStream* output) const override;
308
309 private:
310 // This is called only by the default implementation of ByteSize(), to
311 // update the cached size. If you override ByteSize(), you do not need
312 // to override this. If you do not override ByteSize(), you MUST override
313 // this; the default implementation will crash.
314 //
315 // The method is private because subclasses should never call it; only
316 // override it. Yes, C++ lets you do that. Crazy, huh?
317 virtual void SetCachedSize(int size) const;
318
319 public:
320 // Introspection ---------------------------------------------------
321
322
323 // Get a non-owning pointer to a Descriptor for this message's type. This
324 // describes what fields the message contains, the types of those fields, etc.
325 // This object remains property of the Message.
326 const Descriptor* GetDescriptor() const { return GetMetadata().descriptor; }
327
328 // Get a non-owning pointer to the Reflection interface for this Message,
329 // which can be used to read and modify the fields of the Message dynamically
330 // (in other words, without knowing the message type at compile time). This
331 // object remains property of the Message.
332 //
333 // This method remains virtual in case a subclass does not implement
334 // reflection and wants to override the default behavior.
335 const Reflection* GetReflection() const { return GetMetadata().reflection; }
336
337 protected:
338 // Get a struct containing the metadata for the Message. Most subclasses only
339 // need to implement this method, rather than the GetDescriptor() and
340 // GetReflection() wrappers.
341 virtual Metadata GetMetadata() const = 0;
342
343
344 private:
345 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Message);
346};
347
348namespace internal {
349// Forward-declare interfaces used to implement RepeatedFieldRef.
350// These are protobuf internals that users shouldn't care about.
351class RepeatedFieldAccessor;
352} // namespace internal
353
354// Forward-declare RepeatedFieldRef templates. The second type parameter is
355// used for SFINAE tricks. Users should ignore it.
356template <typename T, typename Enable = void>
357class RepeatedFieldRef;
358
359template <typename T, typename Enable = void>
360class MutableRepeatedFieldRef;
361
362// This interface contains methods that can be used to dynamically access
363// and modify the fields of a protocol message. Their semantics are
364// similar to the accessors the protocol compiler generates.
365//
366// To get the Reflection for a given Message, call Message::GetReflection().
367//
368// This interface is separate from Message only for efficiency reasons;
369// the vast majority of implementations of Message will share the same
370// implementation of Reflection (GeneratedMessageReflection,
371// defined in generated_message.h), and all Messages of a particular class
372// should share the same Reflection object (though you should not rely on
373// the latter fact).
374//
375// There are several ways that these methods can be used incorrectly. For
376// example, any of the following conditions will lead to undefined
377// results (probably assertion failures):
378// - The FieldDescriptor is not a field of this message type.
379// - The method called is not appropriate for the field's type. For
380// each field type in FieldDescriptor::TYPE_*, there is only one
381// Get*() method, one Set*() method, and one Add*() method that is
382// valid for that type. It should be obvious which (except maybe
383// for TYPE_BYTES, which are represented using strings in C++).
384// - A Get*() or Set*() method for singular fields is called on a repeated
385// field.
386// - GetRepeated*(), SetRepeated*(), or Add*() is called on a non-repeated
387// field.
388// - The Message object passed to any method is not of the right type for
389// this Reflection object (i.e. message.GetReflection() != reflection).
390//
391// You might wonder why there is not any abstract representation for a field
392// of arbitrary type. E.g., why isn't there just a "GetField()" method that
393// returns "const Field&", where "Field" is some class with accessors like
394// "GetInt32Value()". The problem is that someone would have to deal with
395// allocating these Field objects. For generated message classes, having to
396// allocate space for an additional object to wrap every field would at least
397// double the message's memory footprint, probably worse. Allocating the
398// objects on-demand, on the other hand, would be expensive and prone to
399// memory leaks. So, instead we ended up with this flat interface.
400class PROTOBUF_EXPORT Reflection final {
401 public:
402 // Get the UnknownFieldSet for the message. This contains fields which
403 // were seen when the Message was parsed but were not recognized according
404 // to the Message's definition.
405 const UnknownFieldSet& GetUnknownFields(const Message& message) const;
406 // Get a mutable pointer to the UnknownFieldSet for the message. This
407 // contains fields which were seen when the Message was parsed but were not
408 // recognized according to the Message's definition.
409 UnknownFieldSet* MutableUnknownFields(Message* message) const;
410
411 // Estimate the amount of memory used by the message object.
412 size_t SpaceUsedLong(const Message& message) const;
413
414 PROTOBUF_DEPRECATED_MSG("Please use SpaceUsedLong() instead")
415 int SpaceUsed(const Message& message) const {
416 return internal::ToIntSize(SpaceUsedLong(message));
417 }
418
419 // Check if the given non-repeated field is set.
420 bool HasField(const Message& message, const FieldDescriptor* field) const;
421
422 // Get the number of elements of a repeated field.
423 int FieldSize(const Message& message, const FieldDescriptor* field) const;
424
425 // Clear the value of a field, so that HasField() returns false or
426 // FieldSize() returns zero.
427 void ClearField(Message* message, const FieldDescriptor* field) const;
428
429 // Check if the oneof is set. Returns true if any field in oneof
430 // is set, false otherwise.
431 bool HasOneof(const Message& message,
432 const OneofDescriptor* oneof_descriptor) const;
433
434 void ClearOneof(Message* message,
435 const OneofDescriptor* oneof_descriptor) const;
436
437 // Returns the field descriptor if the oneof is set. nullptr otherwise.
438 const FieldDescriptor* GetOneofFieldDescriptor(
439 const Message& message, const OneofDescriptor* oneof_descriptor) const;
440
441 // Removes the last element of a repeated field.
442 // We don't provide a way to remove any element other than the last
443 // because it invites inefficient use, such as O(n^2) filtering loops
444 // that should have been O(n). If you want to remove an element other
445 // than the last, the best way to do it is to re-arrange the elements
446 // (using Swap()) so that the one you want removed is at the end, then
447 // call RemoveLast().
448 void RemoveLast(Message* message, const FieldDescriptor* field) const;
449 // Removes the last element of a repeated message field, and returns the
450 // pointer to the caller. Caller takes ownership of the returned pointer.
451 Message* ReleaseLast(Message* message, const FieldDescriptor* field) const;
452
453 // Swap the complete contents of two messages.
454 void Swap(Message* message1, Message* message2) const;
455
456 // Swap fields listed in fields vector of two messages.
457 void SwapFields(Message* message1, Message* message2,
458 const std::vector<const FieldDescriptor*>& fields) const;
459
460 // Swap two elements of a repeated field.
461 void SwapElements(Message* message, const FieldDescriptor* field, int index1,
462 int index2) const;
463
464 // List all fields of the message which are currently set, except for unknown
465 // fields, but including extension known to the parser (i.e. compiled in).
466 // Singular fields will only be listed if HasField(field) would return true
467 // and repeated fields will only be listed if FieldSize(field) would return
468 // non-zero. Fields (both normal fields and extension fields) will be listed
469 // ordered by field number.
470 // Use Reflection::GetUnknownFields() or message.unknown_fields() to also get
471 // access to fields/extensions unknown to the parser.
472 void ListFields(const Message& message,
473 std::vector<const FieldDescriptor*>* output) const;
474
475 // Singular field getters ------------------------------------------
476 // These get the value of a non-repeated field. They return the default
477 // value for fields that aren't set.
478
479 int32 GetInt32(const Message& message, const FieldDescriptor* field) const;
480 int64 GetInt64(const Message& message, const FieldDescriptor* field) const;
481 uint32 GetUInt32(const Message& message, const FieldDescriptor* field) const;
482 uint64 GetUInt64(const Message& message, const FieldDescriptor* field) const;
483 float GetFloat(const Message& message, const FieldDescriptor* field) const;
484 double GetDouble(const Message& message, const FieldDescriptor* field) const;
485 bool GetBool(const Message& message, const FieldDescriptor* field) const;
486 std::string GetString(const Message& message,
487 const FieldDescriptor* field) const;
488 const EnumValueDescriptor* GetEnum(const Message& message,
489 const FieldDescriptor* field) const;
490
491 // GetEnumValue() returns an enum field's value as an integer rather than
492 // an EnumValueDescriptor*. If the integer value does not correspond to a
493 // known value descriptor, a new value descriptor is created. (Such a value
494 // will only be present when the new unknown-enum-value semantics are enabled
495 // for a message.)
496 int GetEnumValue(const Message& message, const FieldDescriptor* field) const;
497
498 // See MutableMessage() for the meaning of the "factory" parameter.
499 const Message& GetMessage(const Message& message,
500 const FieldDescriptor* field,
501 MessageFactory* factory = nullptr) const;
502
503 // Get a string value without copying, if possible.
504 //
505 // GetString() necessarily returns a copy of the string. This can be
506 // inefficient when the std::string is already stored in a std::string object
507 // in the underlying message. GetStringReference() will return a reference to
508 // the underlying std::string in this case. Otherwise, it will copy the
509 // string into *scratch and return that.
510 //
511 // Note: It is perfectly reasonable and useful to write code like:
512 // str = reflection->GetStringReference(message, field, &str);
513 // This line would ensure that only one copy of the string is made
514 // regardless of the field's underlying representation. When initializing
515 // a newly-constructed string, though, it's just as fast and more
516 // readable to use code like:
517 // std::string str = reflection->GetString(message, field);
518 const std::string& GetStringReference(const Message& message,
519 const FieldDescriptor* field,
520 std::string* scratch) const;
521
522
523 // Singular field mutators -----------------------------------------
524 // These mutate the value of a non-repeated field.
525
526 void SetInt32(Message* message, const FieldDescriptor* field,
527 int32 value) const;
528 void SetInt64(Message* message, const FieldDescriptor* field,
529 int64 value) const;
530 void SetUInt32(Message* message, const FieldDescriptor* field,
531 uint32 value) const;
532 void SetUInt64(Message* message, const FieldDescriptor* field,
533 uint64 value) const;
534 void SetFloat(Message* message, const FieldDescriptor* field,
535 float value) const;
536 void SetDouble(Message* message, const FieldDescriptor* field,
537 double value) const;
538 void SetBool(Message* message, const FieldDescriptor* field,
539 bool value) const;
540 void SetString(Message* message, const FieldDescriptor* field,
541 const std::string& value) const;
542 void SetEnum(Message* message, const FieldDescriptor* field,
543 const EnumValueDescriptor* value) const;
544 // Set an enum field's value with an integer rather than EnumValueDescriptor.
545 // For proto3 this is just setting the enum field to the value specified, for
546 // proto2 it's more complicated. If value is a known enum value the field is
547 // set as usual. If the value is unknown then it is added to the unknown field
548 // set. Note this matches the behavior of parsing unknown enum values.
549 // If multiple calls with unknown values happen than they are all added to the
550 // unknown field set in order of the calls.
551 void SetEnumValue(Message* message, const FieldDescriptor* field,
552 int value) const;
553
554 // Get a mutable pointer to a field with a message type. If a MessageFactory
555 // is provided, it will be used to construct instances of the sub-message;
556 // otherwise, the default factory is used. If the field is an extension that
557 // does not live in the same pool as the containing message's descriptor (e.g.
558 // it lives in an overlay pool), then a MessageFactory must be provided.
559 // If you have no idea what that meant, then you probably don't need to worry
560 // about it (don't provide a MessageFactory). WARNING: If the
561 // FieldDescriptor is for a compiled-in extension, then
562 // factory->GetPrototype(field->message_type()) MUST return an instance of
563 // the compiled-in class for this type, NOT DynamicMessage.
564 Message* MutableMessage(Message* message, const FieldDescriptor* field,
565 MessageFactory* factory = nullptr) const;
566 // Replaces the message specified by 'field' with the already-allocated object
567 // sub_message, passing ownership to the message. If the field contained a
568 // message, that message is deleted. If sub_message is nullptr, the field is
569 // cleared.
570 void SetAllocatedMessage(Message* message, Message* sub_message,
571 const FieldDescriptor* field) const;
572 // Releases the message specified by 'field' and returns the pointer,
573 // ReleaseMessage() will return the message the message object if it exists.
574 // Otherwise, it may or may not return nullptr. In any case, if the return
575 // value is non-null, the caller takes ownership of the pointer.
576 // If the field existed (HasField() is true), then the returned pointer will
577 // be the same as the pointer returned by MutableMessage().
578 // This function has the same effect as ClearField().
579 Message* ReleaseMessage(Message* message, const FieldDescriptor* field,
580 MessageFactory* factory = nullptr) const;
581
582
583 // Repeated field getters ------------------------------------------
584 // These get the value of one element of a repeated field.
585
586 int32 GetRepeatedInt32(const Message& message, const FieldDescriptor* field,
587 int index) const;
588 int64 GetRepeatedInt64(const Message& message, const FieldDescriptor* field,
589 int index) const;
590 uint32 GetRepeatedUInt32(const Message& message, const FieldDescriptor* field,
591 int index) const;
592 uint64 GetRepeatedUInt64(const Message& message, const FieldDescriptor* field,
593 int index) const;
594 float GetRepeatedFloat(const Message& message, const FieldDescriptor* field,
595 int index) const;
596 double GetRepeatedDouble(const Message& message, const FieldDescriptor* field,
597 int index) const;
598 bool GetRepeatedBool(const Message& message, const FieldDescriptor* field,
599 int index) const;
600 std::string GetRepeatedString(const Message& message,
601 const FieldDescriptor* field, int index) const;
602 const EnumValueDescriptor* GetRepeatedEnum(const Message& message,
603 const FieldDescriptor* field,
604 int index) const;
605 // GetRepeatedEnumValue() returns an enum field's value as an integer rather
606 // than an EnumValueDescriptor*. If the integer value does not correspond to a
607 // known value descriptor, a new value descriptor is created. (Such a value
608 // will only be present when the new unknown-enum-value semantics are enabled
609 // for a message.)
610 int GetRepeatedEnumValue(const Message& message, const FieldDescriptor* field,
611 int index) const;
612 const Message& GetRepeatedMessage(const Message& message,
613 const FieldDescriptor* field,
614 int index) const;
615
616 // See GetStringReference(), above.
617 const std::string& GetRepeatedStringReference(const Message& message,
618 const FieldDescriptor* field,
619 int index,
620 std::string* scratch) const;
621
622
623 // Repeated field mutators -----------------------------------------
624 // These mutate the value of one element of a repeated field.
625
626 void SetRepeatedInt32(Message* message, const FieldDescriptor* field,
627 int index, int32 value) const;
628 void SetRepeatedInt64(Message* message, const FieldDescriptor* field,
629 int index, int64 value) const;
630 void SetRepeatedUInt32(Message* message, const FieldDescriptor* field,
631 int index, uint32 value) const;
632 void SetRepeatedUInt64(Message* message, const FieldDescriptor* field,
633 int index, uint64 value) const;
634 void SetRepeatedFloat(Message* message, const FieldDescriptor* field,
635 int index, float value) const;
636 void SetRepeatedDouble(Message* message, const FieldDescriptor* field,
637 int index, double value) const;
638 void SetRepeatedBool(Message* message, const FieldDescriptor* field,
639 int index, bool value) const;
640 void SetRepeatedString(Message* message, const FieldDescriptor* field,
641 int index, const std::string& value) const;
642 void SetRepeatedEnum(Message* message, const FieldDescriptor* field,
643 int index, const EnumValueDescriptor* value) const;
644 // Set an enum field's value with an integer rather than EnumValueDescriptor.
645 // For proto3 this is just setting the enum field to the value specified, for
646 // proto2 it's more complicated. If value is a known enum value the field is
647 // set as usual. If the value is unknown then it is added to the unknown field
648 // set. Note this matches the behavior of parsing unknown enum values.
649 // If multiple calls with unknown values happen than they are all added to the
650 // unknown field set in order of the calls.
651 void SetRepeatedEnumValue(Message* message, const FieldDescriptor* field,
652 int index, int value) const;
653 // Get a mutable pointer to an element of a repeated field with a message
654 // type.
655 Message* MutableRepeatedMessage(Message* message,
656 const FieldDescriptor* field,
657 int index) const;
658
659
660 // Repeated field adders -------------------------------------------
661 // These add an element to a repeated field.
662
663 void AddInt32(Message* message, const FieldDescriptor* field,
664 int32 value) const;
665 void AddInt64(Message* message, const FieldDescriptor* field,
666 int64 value) const;
667 void AddUInt32(Message* message, const FieldDescriptor* field,
668 uint32 value) const;
669 void AddUInt64(Message* message, const FieldDescriptor* field,
670 uint64 value) const;
671 void AddFloat(Message* message, const FieldDescriptor* field,
672 float value) const;
673 void AddDouble(Message* message, const FieldDescriptor* field,
674 double value) const;
675 void AddBool(Message* message, const FieldDescriptor* field,
676 bool value) const;
677 void AddString(Message* message, const FieldDescriptor* field,
678 const std::string& value) const;
679 void AddEnum(Message* message, const FieldDescriptor* field,
680 const EnumValueDescriptor* value) const;
681 // Add an integer value to a repeated enum field rather than
682 // EnumValueDescriptor. For proto3 this is just setting the enum field to the
683 // value specified, for proto2 it's more complicated. If value is a known enum
684 // value the field is set as usual. If the value is unknown then it is added
685 // to the unknown field set. Note this matches the behavior of parsing unknown
686 // enum values. If multiple calls with unknown values happen than they are all
687 // added to the unknown field set in order of the calls.
688 void AddEnumValue(Message* message, const FieldDescriptor* field,
689 int value) const;
690 // See MutableMessage() for comments on the "factory" parameter.
691 Message* AddMessage(Message* message, const FieldDescriptor* field,
692 MessageFactory* factory = nullptr) const;
693
694 // Appends an already-allocated object 'new_entry' to the repeated field
695 // specified by 'field' passing ownership to the message.
696 void AddAllocatedMessage(Message* message, const FieldDescriptor* field,
697 Message* new_entry) const;
698
699
700 // Get a RepeatedFieldRef object that can be used to read the underlying
701 // repeated field. The type parameter T must be set according to the
702 // field's cpp type. The following table shows the mapping from cpp type
703 // to acceptable T.
704 //
705 // field->cpp_type() T
706 // CPPTYPE_INT32 int32
707 // CPPTYPE_UINT32 uint32
708 // CPPTYPE_INT64 int64
709 // CPPTYPE_UINT64 uint64
710 // CPPTYPE_DOUBLE double
711 // CPPTYPE_FLOAT float
712 // CPPTYPE_BOOL bool
713 // CPPTYPE_ENUM generated enum type or int32
714 // CPPTYPE_STRING std::string
715 // CPPTYPE_MESSAGE generated message type or google::protobuf::Message
716 //
717 // A RepeatedFieldRef object can be copied and the resulted object will point
718 // to the same repeated field in the same message. The object can be used as
719 // long as the message is not destroyed.
720 //
721 // Note that to use this method users need to include the header file
722 // "net/proto2/public/reflection.h" (which defines the RepeatedFieldRef
723 // class templates).
724 template <typename T>
725 RepeatedFieldRef<T> GetRepeatedFieldRef(const Message& message,
726 const FieldDescriptor* field) const;
727
728 // Like GetRepeatedFieldRef() but return an object that can also be used
729 // manipulate the underlying repeated field.
730 template <typename T>
731 MutableRepeatedFieldRef<T> GetMutableRepeatedFieldRef(
732 Message* message, const FieldDescriptor* field) const;
733
734 // DEPRECATED. Please use Get(Mutable)RepeatedFieldRef() for repeated field
735 // access. The following repeated field accesors will be removed in the
736 // future.
737 //
738 // Repeated field accessors -------------------------------------------------
739 // The methods above, e.g. GetRepeatedInt32(msg, fd, index), provide singular
740 // access to the data in a RepeatedField. The methods below provide aggregate
741 // access by exposing the RepeatedField object itself with the Message.
742 // Applying these templates to inappropriate types will lead to an undefined
743 // reference at link time (e.g. GetRepeatedField<***double>), or possibly a
744 // template matching error at compile time (e.g. GetRepeatedPtrField<File>).
745 //
746 // Usage example: my_doubs = refl->GetRepeatedField<double>(msg, fd);
747
748 // DEPRECATED. Please use GetRepeatedFieldRef().
749 //
750 // for T = Cord and all protobuf scalar types except enums.
751 template <typename T>
752 PROTOBUF_DEPRECATED_MSG("Please use GetRepeatedFieldRef() instead")
753 const RepeatedField<T>& GetRepeatedField(const Message&,
754 const FieldDescriptor*) const;
755
756 // DEPRECATED. Please use GetMutableRepeatedFieldRef().
757 //
758 // for T = Cord and all protobuf scalar types except enums.
759 template <typename T>
760 PROTOBUF_DEPRECATED_MSG("Please use GetMutableRepeatedFieldRef() instead")
761 RepeatedField<T>* MutableRepeatedField(Message*,
762 const FieldDescriptor*) const;
763
764 // DEPRECATED. Please use GetRepeatedFieldRef().
765 //
766 // for T = std::string, google::protobuf::internal::StringPieceField
767 // google::protobuf::Message & descendants.
768 template <typename T>
769 PROTOBUF_DEPRECATED_MSG("Please use GetRepeatedFieldRef() instead")
770 const RepeatedPtrField<T>& GetRepeatedPtrField(const Message&,
771 const FieldDescriptor*) const;
772
773 // DEPRECATED. Please use GetMutableRepeatedFieldRef().
774 //
775 // for T = std::string, google::protobuf::internal::StringPieceField
776 // google::protobuf::Message & descendants.
777 template <typename T>
778 PROTOBUF_DEPRECATED_MSG("Please use GetMutableRepeatedFieldRef() instead")
779 RepeatedPtrField<T>* MutableRepeatedPtrField(Message*,
780 const FieldDescriptor*) const;
781
782 // Extensions ----------------------------------------------------------------
783
784 // Try to find an extension of this message type by fully-qualified field
785 // name. Returns nullptr if no extension is known for this name or number.
786 PROTOBUF_DEPRECATED_MSG(
787 "Please use DescriptorPool::FindExtensionByPrintableName instead")
788 const FieldDescriptor* FindKnownExtensionByName(
789 const std::string& name) const;
790
791 // Try to find an extension of this message type by field number.
792 // Returns nullptr if no extension is known for this name or number.
793 PROTOBUF_DEPRECATED_MSG(
794 "Please use DescriptorPool::FindExtensionByNumber instead")
795 const FieldDescriptor* FindKnownExtensionByNumber(int number) const;
796
797 // Feature Flags -------------------------------------------------------------
798
799 // Does this message support storing arbitrary integer values in enum fields?
800 // If |true|, GetEnumValue/SetEnumValue and associated repeated-field versions
801 // take arbitrary integer values, and the legacy GetEnum() getter will
802 // dynamically create an EnumValueDescriptor for any integer value without
803 // one. If |false|, setting an unknown enum value via the integer-based
804 // setters results in undefined behavior (in practice, GOOGLE_DCHECK-fails).
805 //
806 // Generic code that uses reflection to handle messages with enum fields
807 // should check this flag before using the integer-based setter, and either
808 // downgrade to a compatible value or use the UnknownFieldSet if not. For
809 // example:
810 //
811 // int new_value = GetValueFromApplicationLogic();
812 // if (reflection->SupportsUnknownEnumValues()) {
813 // reflection->SetEnumValue(message, field, new_value);
814 // } else {
815 // if (field_descriptor->enum_type()->
816 // FindValueByNumber(new_value) != nullptr) {
817 // reflection->SetEnumValue(message, field, new_value);
818 // } else if (emit_unknown_enum_values) {
819 // reflection->MutableUnknownFields(message)->AddVarint(
820 // field->number(), new_value);
821 // } else {
822 // // convert value to a compatible/default value.
823 // new_value = CompatibleDowngrade(new_value);
824 // reflection->SetEnumValue(message, field, new_value);
825 // }
826 // }
827 bool SupportsUnknownEnumValues() const;
828
829 // Returns the MessageFactory associated with this message. This can be
830 // useful for determining if a message is a generated message or not, for
831 // example:
832 // if (message->GetReflection()->GetMessageFactory() ==
833 // google::protobuf::MessageFactory::generated_factory()) {
834 // // This is a generated message.
835 // }
836 // It can also be used to create more messages of this type, though
837 // Message::New() is an easier way to accomplish this.
838 MessageFactory* GetMessageFactory() const;
839
840 private:
841 // Obtain a pointer to a Repeated Field Structure and do some type checking:
842 // on field->cpp_type(),
843 // on field->field_option().ctype() (if ctype >= 0)
844 // of field->message_type() (if message_type != nullptr).
845 // We use 2 routine rather than 4 (const vs mutable) x (scalar vs pointer).
846 void* MutableRawRepeatedField(Message* message, const FieldDescriptor* field,
847 FieldDescriptor::CppType, int ctype,
848 const Descriptor* message_type) const;
849
850 const void* GetRawRepeatedField(const Message& message,
851 const FieldDescriptor* field,
852 FieldDescriptor::CppType cpptype, int ctype,
853 const Descriptor* message_type) const;
854
855 // The following methods are used to implement (Mutable)RepeatedFieldRef.
856 // A Ref object will store a raw pointer to the repeated field data (obtained
857 // from RepeatedFieldData()) and a pointer to a Accessor (obtained from
858 // RepeatedFieldAccessor) which will be used to access the raw data.
859
860 // Returns a raw pointer to the repeated field
861 //
862 // "cpp_type" and "message_type" are deduced from the type parameter T passed
863 // to Get(Mutable)RepeatedFieldRef. If T is a generated message type,
864 // "message_type" should be set to its descriptor. Otherwise "message_type"
865 // should be set to nullptr. Implementations of this method should check
866 // whether "cpp_type"/"message_type" is consistent with the actual type of the
867 // field. We use 1 routine rather than 2 (const vs mutable) because it is
868 // protected and it doesn't change the message.
869 void* RepeatedFieldData(Message* message, const FieldDescriptor* field,
870 FieldDescriptor::CppType cpp_type,
871 const Descriptor* message_type) const;
872
873 // The returned pointer should point to a singleton instance which implements
874 // the RepeatedFieldAccessor interface.
875 const internal::RepeatedFieldAccessor* RepeatedFieldAccessor(
876 const FieldDescriptor* field) const;
877
878 const Descriptor* const descriptor_;
879 const internal::ReflectionSchema schema_;
880 const DescriptorPool* const descriptor_pool_;
881 MessageFactory* const message_factory_;
882
883 // Last non weak field index. This is an optimization when most weak fields
884 // are at the end of the containing message. If a message proto doesn't
885 // contain weak fields, then this field equals descriptor_->field_count().
886 int last_non_weak_field_index_;
887
888 template <typename T, typename Enable>
889 friend class RepeatedFieldRef;
890 template <typename T, typename Enable>
891 friend class MutableRepeatedFieldRef;
892 friend class ::PROTOBUF_NAMESPACE_ID::MessageLayoutInspector;
893 friend class ::PROTOBUF_NAMESPACE_ID::AssignDescriptorsHelper;
894 friend class DynamicMessageFactory;
895 friend class python::MapReflectionFriend;
896#define GOOGLE_PROTOBUF_HAS_CEL_MAP_REFLECTION_FRIEND
897 friend class expr::CelMapReflectionFriend;
898 friend class internal::MapFieldReflectionTest;
899 friend class internal::MapKeySorter;
900 friend class internal::WireFormat;
901 friend class internal::ReflectionOps;
902 // Needed for implementing text format for map.
903 friend class internal::MapFieldPrinterHelper;
904 friend class internal::ReflectionAccessor;
905
906 Reflection(const Descriptor* descriptor,
907 const internal::ReflectionSchema& schema,
908 const DescriptorPool* pool, MessageFactory* factory);
909
910 // Special version for specialized implementations of string. We can't
911 // call MutableRawRepeatedField directly here because we don't have access to
912 // FieldOptions::* which are defined in descriptor.pb.h. Including that
913 // file here is not possible because it would cause a circular include cycle.
914 // We use 1 routine rather than 2 (const vs mutable) because it is private
915 // and mutable a repeated string field doesn't change the message.
916 void* MutableRawRepeatedString(Message* message, const FieldDescriptor* field,
917 bool is_string) const;
918
919 friend class MapReflectionTester;
920 // Returns true if key is in map. Returns false if key is not in map field.
921 bool ContainsMapKey(const Message& message, const FieldDescriptor* field,
922 const MapKey& key) const;
923
924 // If key is in map field: Saves the value pointer to val and returns
925 // false. If key in not in map field: Insert the key into map, saves
926 // value pointer to val and retuns true.
927 bool InsertOrLookupMapValue(Message* message, const FieldDescriptor* field,
928 const MapKey& key, MapValueRef* val) const;
929
930 // Delete and returns true if key is in the map field. Returns false
931 // otherwise.
932 bool DeleteMapValue(Message* message, const FieldDescriptor* field,
933 const MapKey& key) const;
934
935 // Returns a MapIterator referring to the first element in the map field.
936 // If the map field is empty, this function returns the same as
937 // reflection::MapEnd. Mutation to the field may invalidate the iterator.
938 MapIterator MapBegin(Message* message, const FieldDescriptor* field) const;
939
940 // Returns a MapIterator referring to the theoretical element that would
941 // follow the last element in the map field. It does not point to any
942 // real element. Mutation to the field may invalidate the iterator.
943 MapIterator MapEnd(Message* message, const FieldDescriptor* field) const;
944
945 // Get the number of <key, value> pair of a map field. The result may be
946 // different from FieldSize which can have duplicate keys.
947 int MapSize(const Message& message, const FieldDescriptor* field) const;
948
949 // Help method for MapIterator.
950 friend class MapIterator;
951 internal::MapFieldBase* MutableMapData(Message* message,
952 const FieldDescriptor* field) const;
953
954 const internal::MapFieldBase* GetMapData(const Message& message,
955 const FieldDescriptor* field) const;
956
957 template <class T>
958 const T& GetRawNonOneof(const Message& message,
959 const FieldDescriptor* field) const;
960 template <class T>
961 T* MutableRawNonOneof(Message* message, const FieldDescriptor* field) const;
962
963 template <typename Type>
964 const Type& GetRaw(const Message& message,
965 const FieldDescriptor* field) const;
966 template <typename Type>
967 inline Type* MutableRaw(Message* message, const FieldDescriptor* field) const;
968 template <typename Type>
969 inline const Type& DefaultRaw(const FieldDescriptor* field) const;
970
971 inline const uint32* GetHasBits(const Message& message) const;
972 inline uint32* MutableHasBits(Message* message) const;
973 inline uint32 GetOneofCase(const Message& message,
974 const OneofDescriptor* oneof_descriptor) const;
975 inline uint32* MutableOneofCase(
976 Message* message, const OneofDescriptor* oneof_descriptor) const;
977 inline const internal::ExtensionSet& GetExtensionSet(
978 const Message& message) const;
979 inline internal::ExtensionSet* MutableExtensionSet(Message* message) const;
980 inline Arena* GetArena(Message* message) const;
981
982 inline const internal::InternalMetadataWithArena&
983 GetInternalMetadataWithArena(const Message& message) const;
984
985 internal::InternalMetadataWithArena* MutableInternalMetadataWithArena(
986 Message* message) const;
987
988 inline bool IsInlined(const FieldDescriptor* field) const;
989
990 inline bool HasBit(const Message& message,
991 const FieldDescriptor* field) const;
992 inline void SetBit(Message* message, const FieldDescriptor* field) const;
993 inline void ClearBit(Message* message, const FieldDescriptor* field) const;
994 inline void SwapBit(Message* message1, Message* message2,
995 const FieldDescriptor* field) const;
996
997 // This function only swaps the field. Should swap corresponding has_bit
998 // before or after using this function.
999 void SwapField(Message* message1, Message* message2,
1000 const FieldDescriptor* field) const;
1001
1002 void SwapOneofField(Message* message1, Message* message2,
1003 const OneofDescriptor* oneof_descriptor) const;
1004
1005 inline bool HasOneofField(const Message& message,
1006 const FieldDescriptor* field) const;
1007 inline void SetOneofCase(Message* message,
1008 const FieldDescriptor* field) const;
1009 inline void ClearOneofField(Message* message,
1010 const FieldDescriptor* field) const;
1011
1012 template <typename Type>
1013 inline const Type& GetField(const Message& message,
1014 const FieldDescriptor* field) const;
1015 template <typename Type>
1016 inline void SetField(Message* message, const FieldDescriptor* field,
1017 const Type& value) const;
1018 template <typename Type>
1019 inline Type* MutableField(Message* message,
1020 const FieldDescriptor* field) const;
1021 template <typename Type>
1022 inline const Type& GetRepeatedField(const Message& message,
1023 const FieldDescriptor* field,
1024 int index) const;
1025 template <typename Type>
1026 inline const Type& GetRepeatedPtrField(const Message& message,
1027 const FieldDescriptor* field,
1028 int index) const;
1029 template <typename Type>
1030 inline void SetRepeatedField(Message* message, const FieldDescriptor* field,
1031 int index, Type value) const;
1032 template <typename Type>
1033 inline Type* MutableRepeatedField(Message* message,
1034 const FieldDescriptor* field,
1035 int index) const;
1036 template <typename Type>
1037 inline void AddField(Message* message, const FieldDescriptor* field,
1038 const Type& value) const;
1039 template <typename Type>
1040 inline Type* AddField(Message* message, const FieldDescriptor* field) const;
1041
1042 int GetExtensionNumberOrDie(const Descriptor* type) const;
1043
1044 // Internal versions of EnumValue API perform no checking. Called after checks
1045 // by public methods.
1046 void SetEnumValueInternal(Message* message, const FieldDescriptor* field,
1047 int value) const;
1048 void SetRepeatedEnumValueInternal(Message* message,
1049 const FieldDescriptor* field, int index,
1050 int value) const;
1051 void AddEnumValueInternal(Message* message, const FieldDescriptor* field,
1052 int value) const;
1053
1054 Message* UnsafeArenaReleaseMessage(Message* message,
1055 const FieldDescriptor* field,
1056 MessageFactory* factory = nullptr) const;
1057
1058 void UnsafeArenaSetAllocatedMessage(Message* message, Message* sub_message,
1059 const FieldDescriptor* field) const;
1060
1061 friend inline // inline so nobody can call this function.
1062 void
1063 RegisterAllTypesInternal(const Metadata* file_level_metadata, int size);
1064
1065 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Reflection);
1066};
1067
1068// Abstract interface for a factory for message objects.
1069class PROTOBUF_EXPORT MessageFactory {
1070 public:
1071 inline MessageFactory() {}
1072 virtual ~MessageFactory();
1073
1074 // Given a Descriptor, gets or constructs the default (prototype) Message
1075 // of that type. You can then call that message's New() method to construct
1076 // a mutable message of that type.
1077 //
1078 // Calling this method twice with the same Descriptor returns the same
1079 // object. The returned object remains property of the factory. Also, any
1080 // objects created by calling the prototype's New() method share some data
1081 // with the prototype, so these must be destroyed before the MessageFactory
1082 // is destroyed.
1083 //
1084 // The given descriptor must outlive the returned message, and hence must
1085 // outlive the MessageFactory.
1086 //
1087 // Some implementations do not support all types. GetPrototype() will
1088 // return nullptr if the descriptor passed in is not supported.
1089 //
1090 // This method may or may not be thread-safe depending on the implementation.
1091 // Each implementation should document its own degree thread-safety.
1092 virtual const Message* GetPrototype(const Descriptor* type) = 0;
1093
1094 // Gets a MessageFactory which supports all generated, compiled-in messages.
1095 // In other words, for any compiled-in type FooMessage, the following is true:
1096 // MessageFactory::generated_factory()->GetPrototype(
1097 // FooMessage::descriptor()) == FooMessage::default_instance()
1098 // This factory supports all types which are found in
1099 // DescriptorPool::generated_pool(). If given a descriptor from any other
1100 // pool, GetPrototype() will return nullptr. (You can also check if a
1101 // descriptor is for a generated message by checking if
1102 // descriptor->file()->pool() == DescriptorPool::generated_pool().)
1103 //
1104 // This factory is 100% thread-safe; calling GetPrototype() does not modify
1105 // any shared data.
1106 //
1107 // This factory is a singleton. The caller must not delete the object.
1108 static MessageFactory* generated_factory();
1109
1110 // For internal use only: Registers a .proto file at static initialization
1111 // time, to be placed in generated_factory. The first time GetPrototype()
1112 // is called with a descriptor from this file, |register_messages| will be
1113 // called, with the file name as the parameter. It must call
1114 // InternalRegisterGeneratedMessage() (below) to register each message type
1115 // in the file. This strange mechanism is necessary because descriptors are
1116 // built lazily, so we can't register types by their descriptor until we
1117 // know that the descriptor exists. |filename| must be a permanent string.
1118 static void InternalRegisterGeneratedFile(
1119 const google::protobuf::internal::DescriptorTable* table);
1120
1121 // For internal use only: Registers a message type. Called only by the
1122 // functions which are registered with InternalRegisterGeneratedFile(),
1123 // above.
1124 static void InternalRegisterGeneratedMessage(const Descriptor* descriptor,
1125 const Message* prototype);
1126
1127
1128 private:
1129 GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageFactory);
1130};
1131
1132#define DECLARE_GET_REPEATED_FIELD(TYPE) \
1133 template <> \
1134 PROTOBUF_EXPORT const RepeatedField<TYPE>& \
1135 Reflection::GetRepeatedField<TYPE>(const Message& message, \
1136 const FieldDescriptor* field) const; \
1137 \
1138 template <> \
1139 PROTOBUF_EXPORT RepeatedField<TYPE>* Reflection::MutableRepeatedField<TYPE>( \
1140 Message * message, const FieldDescriptor* field) const;
1141
1142DECLARE_GET_REPEATED_FIELD(int32)
1143DECLARE_GET_REPEATED_FIELD(int64)
1144DECLARE_GET_REPEATED_FIELD(uint32)
1145DECLARE_GET_REPEATED_FIELD(uint64)
1146DECLARE_GET_REPEATED_FIELD(float)
1147DECLARE_GET_REPEATED_FIELD(double)
1148DECLARE_GET_REPEATED_FIELD(bool)
1149
1150#undef DECLARE_GET_REPEATED_FIELD
1151
1152// Tries to downcast this message to a generated message type. Returns nullptr
1153// if this class is not an instance of T. This works even if RTTI is disabled.
1154//
1155// This also has the effect of creating a strong reference to T that will
1156// prevent the linker from stripping it out at link time. This can be important
1157// if you are using a DynamicMessageFactory that delegates to the generated
1158// factory.
1159template <typename T>
1160const T* DynamicCastToGenerated(const Message* from) {
1161 // Compile-time assert that T is a generated type that has a
1162 // default_instance() accessor, but avoid actually calling it.
1163 const T& (*get_default_instance)() = &T::default_instance;
1164 (void)get_default_instance;
1165
1166 // Compile-time assert that T is a subclass of google::protobuf::Message.
1167 const Message* unused = static_cast<T*>(nullptr);
1168 (void)unused;
1169
1170#ifdef GOOGLE_PROTOBUF_NO_RTTI
1171 bool ok = T::default_instance().GetReflection() == from->GetReflection();
1172 return ok ? down_cast<const T*>(from) : nullptr;
1173#else
1174 return dynamic_cast<const T*>(from);
1175#endif
1176}
1177
1178template <typename T>
1179T* DynamicCastToGenerated(Message* from) {
1180 const Message* message_const = from;
1181 return const_cast<T*>(DynamicCastToGenerated<T>(message_const));
1182}
1183
1184// Call this function to ensure that this message's reflection is linked into
1185// the binary:
1186//
1187// google::protobuf::LinkMessageReflection<FooMessage>();
1188//
1189// This will ensure that the following lookup will succeed:
1190//
1191// DescriptorPool::generated_pool()->FindMessageTypeByName("FooMessage");
1192//
1193// As a side-effect, it will also guarantee that anything else from the same
1194// .proto file will also be available for lookup in the generated pool.
1195//
1196// This function does not actually register the message, so it does not need
1197// to be called before the lookup. However it does need to occur in a function
1198// that cannot be stripped from the binary (ie. it must be reachable from main).
1199//
1200// Best practice is to call this function as close as possible to where the
1201// reflection is actually needed. This function is very cheap to call, so you
1202// should not need to worry about its runtime overhead except in the tightest
1203// of loops (on x86-64 it compiles into two "mov" instructions).
1204template <typename T>
1205void LinkMessageReflection() {
1206 typedef const T& GetDefaultInstanceFunction();
1207 GetDefaultInstanceFunction* volatile unused = &T::default_instance;
1208 (void)&unused; // Use address to avoid an extra load of volatile variable.
1209}
1210
1211// =============================================================================
1212// Implementation details for {Get,Mutable}RawRepeatedPtrField. We provide
1213// specializations for <std::string>, <StringPieceField> and <Message> and
1214// handle everything else with the default template which will match any type
1215// having a method with signature "static const google::protobuf::Descriptor*
1216// descriptor()". Such a type presumably is a descendant of google::protobuf::Message.
1217
1218template <>
1219inline const RepeatedPtrField<std::string>&
1220Reflection::GetRepeatedPtrField<std::string>(
1221 const Message& message, const FieldDescriptor* field) const {
1222 return *static_cast<RepeatedPtrField<std::string>*>(
1223 MutableRawRepeatedString(const_cast<Message*>(&message), field, true));
1224}
1225
1226template <>
1227inline RepeatedPtrField<std::string>*
1228Reflection::MutableRepeatedPtrField<std::string>(
1229 Message* message, const FieldDescriptor* field) const {
1230 return static_cast<RepeatedPtrField<std::string>*>(
1231 MutableRawRepeatedString(message, field, true));
1232}
1233
1234
1235// -----
1236
1237template <>
1238inline const RepeatedPtrField<Message>& Reflection::GetRepeatedPtrField(
1239 const Message& message, const FieldDescriptor* field) const {
1240 return *static_cast<const RepeatedPtrField<Message>*>(GetRawRepeatedField(
1241 message, field, FieldDescriptor::CPPTYPE_MESSAGE, -1, nullptr));
1242}
1243
1244template <>
1245inline RepeatedPtrField<Message>* Reflection::MutableRepeatedPtrField(
1246 Message* message, const FieldDescriptor* field) const {
1247 return static_cast<RepeatedPtrField<Message>*>(MutableRawRepeatedField(
1248 message, field, FieldDescriptor::CPPTYPE_MESSAGE, -1, nullptr));
1249}
1250
1251template <typename PB>
1252inline const RepeatedPtrField<PB>& Reflection::GetRepeatedPtrField(
1253 const Message& message, const FieldDescriptor* field) const {
1254 return *static_cast<const RepeatedPtrField<PB>*>(
1255 GetRawRepeatedField(message, field, FieldDescriptor::CPPTYPE_MESSAGE, -1,
1256 PB::default_instance().GetDescriptor()));
1257}
1258
1259template <typename PB>
1260inline RepeatedPtrField<PB>* Reflection::MutableRepeatedPtrField(
1261 Message* message, const FieldDescriptor* field) const {
1262 return static_cast<RepeatedPtrField<PB>*>(
1263 MutableRawRepeatedField(message, field, FieldDescriptor::CPPTYPE_MESSAGE,
1264 -1, PB::default_instance().GetDescriptor()));
1265}
1266} // namespace protobuf
1267} // namespace google
1268
1269#include <google/protobuf/port_undef.inc>
1270
1271#endif // GOOGLE_PROTOBUF_MESSAGE_H__
1272