// Protocol Buffers - Google's data interchange format // Copyright 2008 Google Inc. All rights reserved. // https://developers.google.com/protocol-buffers/ // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // Authors: wink@google.com (Wink Saville), // kenton@google.com (Kenton Varda) // Based on original Protocol Buffers design by // Sanjay Ghemawat, Jeff Dean, and others. // // Defines MessageLite, the abstract interface implemented by all (lite // and non-lite) protocol message objects. #ifndef GOOGLE_PROTOBUF_MESSAGE_LITE_H__ #define GOOGLE_PROTOBUF_MESSAGE_LITE_H__ #include #include #include #include #include #include #include #include #include #include #include #ifdef SWIG #error "You cannot SWIG proto headers" #endif namespace google { namespace protobuf { template class RepeatedPtrField; class FastReflectionMessageMutator; class FastReflectionStringSetter; class Reflection; namespace io { class CodedInputStream; class CodedOutputStream; class ZeroCopyInputStream; class ZeroCopyOutputStream; } // namespace io namespace internal { class SwapFieldHelper; // Tag type used to invoke the constinit constructor overload of some classes. // Such constructors are internal implementation details of the library. struct ConstantInitialized { explicit ConstantInitialized() = default; }; // See parse_context.h for explanation class ParseContext; class ExtensionSet; class LazyField; class RepeatedPtrFieldBase; class TcParserBase; class WireFormatLite; class WeakFieldMap; template class GenericTypeHandler; // defined in repeated_field.h // We compute sizes as size_t but cache them as int. This function converts a // computed size to a cached size. Since we don't proceed with serialization // if the total size was > INT_MAX, it is not important what this function // returns for inputs > INT_MAX. However this case should not error or // GOOGLE_CHECK-fail, because the full size_t resolution is still returned from // ByteSizeLong() and checked against INT_MAX; we can catch the overflow // there. inline int ToCachedSize(size_t size) { return static_cast(size); } // We mainly calculate sizes in terms of size_t, but some functions that // compute sizes return "int". These int sizes are expected to always be // positive. This function is more efficient than casting an int to size_t // directly on 64-bit platforms because it avoids making the compiler emit a // sign extending instruction, which we don't want and don't want to pay for. inline size_t FromIntSize(int size) { // Convert to unsigned before widening so sign extension is not necessary. return static_cast(size); } // For cases where a legacy function returns an integer size. We GOOGLE_DCHECK() // that the conversion will fit within an integer; if this is false then we // are losing information. inline int ToIntSize(size_t size) { GOOGLE_DCHECK_LE(size, static_cast(INT_MAX)); return static_cast(size); } // This type wraps a variable whose constructor and destructor are explicitly // called. It is particularly useful for a global variable, without its // constructor and destructor run on start and end of the program lifetime. // This circumvents the initial construction order fiasco, while keeping // the address of the empty string a compile time constant. // // Pay special attention to the initialization state of the object. // 1. The object is "uninitialized" to begin with. // 2. Call Construct() or DefaultConstruct() only if the object is // uninitialized. After the call, the object becomes "initialized". // 3. Call get() and get_mutable() only if the object is initialized. // 4. Call Destruct() only if the object is initialized. // After the call, the object becomes uninitialized. template class ExplicitlyConstructed { public: void DefaultConstruct() { new (&union_) T(); } template void Construct(Args&&... args) { new (&union_) T(std::forward(args)...); } void Destruct() { get_mutable()->~T(); } constexpr const T& get() const { return reinterpret_cast(union_); } T* get_mutable() { return reinterpret_cast(&union_); } private: // Prefer c++14 aligned_storage, but for compatibility this will do. union AlignedUnion { alignas(T) char space[sizeof(T)]; int64_t align_to_int64; void* align_to_ptr; } union_; }; // Default empty string object. Don't use this directly. Instead, call // GetEmptyString() to get the reference. PROTOBUF_EXPORT extern ExplicitlyConstructed fixed_address_empty_string; PROTOBUF_EXPORT constexpr const std::string& GetEmptyStringAlreadyInited() { return fixed_address_empty_string.get(); } PROTOBUF_EXPORT size_t StringSpaceUsedExcludingSelfLong(const std::string& str); } // namespace internal // Interface to light weight protocol messages. // // This interface is implemented by all protocol message objects. Non-lite // messages additionally implement the Message interface, which is a // subclass of MessageLite. Use MessageLite instead when you only need // the subset of features which it supports -- namely, nothing that uses // descriptors or reflection. You can instruct the protocol compiler // to generate classes which implement only MessageLite, not the full // Message interface, by adding the following line to the .proto file: // // option optimize_for = LITE_RUNTIME; // // This is particularly useful on resource-constrained systems where // the full protocol buffers runtime library is too big. // // Note that on non-constrained systems (e.g. servers) when you need // to link in lots of protocol definitions, a better way to reduce // total code footprint is to use optimize_for = CODE_SIZE. This // will make the generated code smaller while still supporting all the // same features (at the expense of speed). optimize_for = LITE_RUNTIME // is best when you only have a small number of message types linked // into your binary, in which case the size of the protocol buffers // runtime itself is the biggest problem. // // Users must not derive from this class. Only the protocol compiler and // the internal library are allowed to create subclasses. class PROTOBUF_EXPORT MessageLite { public: constexpr MessageLite() {} virtual ~MessageLite() = default; // Basic Operations ------------------------------------------------ // Get the name of this message type, e.g. "foo.bar.BazProto". virtual std::string GetTypeName() const = 0; // Construct a new instance of the same type. Ownership is passed to the // caller. virtual MessageLite* New() const = 0; // Construct a new instance on the arena. Ownership is passed to the caller // if arena is a NULL. Default implementation for backwards compatibility. virtual MessageLite* New(Arena* arena) const; // Same as GetOwningArena. Arena* GetArena() const { return GetOwningArena(); } // Get a pointer that may be equal to this message's arena, or may not be. // If the value returned by this method is equal to some arena pointer, then // this message is on that arena; however, if this message is on some arena, // this method may or may not return that arena's pointer. As a tradeoff, // this method may be more efficient than GetArena(). The intent is to allow // underlying representations that use e.g. tagged pointers to sometimes // store the arena pointer directly, and sometimes in a more indirect way, // and allow a fastpath comparison against the arena pointer when it's easy // to obtain. void* GetMaybeArenaPointer() const { return _internal_metadata_.raw_arena_ptr(); } // Clear all fields of the message and set them to their default values. // Clear() avoids freeing memory, assuming that any memory allocated // to hold parts of the message will be needed again to hold the next // message. If you actually want to free the memory used by a Message, // you must delete it. virtual void Clear() = 0; // Quickly check if all required fields have values set. virtual bool IsInitialized() const = 0; // This is not implemented for Lite messages -- it just returns "(cannot // determine missing fields for lite message)". However, it is implemented // for full messages. See message.h. virtual std::string InitializationErrorString() const; // If |other| is the exact same class as this, calls MergeFrom(). Otherwise, // results are undefined (probably crash). virtual void CheckTypeAndMergeFrom(const MessageLite& other) = 0; // These methods return a human-readable summary of the message. Note that // since the MessageLite interface does not support reflection, there is very // little information that these methods can provide. They are shadowed by // methods of the same name on the Message interface which provide much more // information. The methods here are intended primarily to facilitate code // reuse for logic that needs to interoperate with both full and lite protos. // // The format of the returned string is subject to change, so please do not // assume it will remain stable over time. std::string DebugString() const; std::string ShortDebugString() const { return DebugString(); } // MessageLite::DebugString is already Utf8 Safe. This is to add compatibility // with Message. std::string Utf8DebugString() const { return DebugString(); } // Parsing --------------------------------------------------------- // Methods for parsing in protocol buffer format. Most of these are // just simple wrappers around MergeFromCodedStream(). Clear() will be // called before merging the input. // Fill the message with a protocol buffer parsed from the given input // stream. Returns false on a read error or if the input is in the wrong // format. A successful return does not indicate the entire input is // consumed, ensure you call ConsumedEntireMessage() to check that if // applicable. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromCodedStream( io::CodedInputStream* input); // Like ParseFromCodedStream(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromCodedStream( io::CodedInputStream* input); // Read a protocol buffer from the given zero-copy input stream. If // successful, the entire input will be consumed. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromZeroCopyStream( io::ZeroCopyInputStream* input); // Like ParseFromZeroCopyStream(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromZeroCopyStream( io::ZeroCopyInputStream* input); // Parse a protocol buffer from a file descriptor. If successful, the entire // input will be consumed. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromFileDescriptor( int file_descriptor); // Like ParseFromFileDescriptor(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromFileDescriptor( int file_descriptor); // Parse a protocol buffer from a C++ istream. If successful, the entire // input will be consumed. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromIstream(std::istream* input); // Like ParseFromIstream(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromIstream( std::istream* input); // Read a protocol buffer from the given zero-copy input stream, expecting // the message to be exactly "size" bytes long. If successful, exactly // this many bytes will have been consumed from the input. bool MergePartialFromBoundedZeroCopyStream(io::ZeroCopyInputStream* input, int size); // Like ParseFromBoundedZeroCopyStream(), but accepts messages that are // missing required fields. bool MergeFromBoundedZeroCopyStream(io::ZeroCopyInputStream* input, int size); PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromBoundedZeroCopyStream( io::ZeroCopyInputStream* input, int size); // Like ParseFromBoundedZeroCopyStream(), but accepts messages that are // missing required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromBoundedZeroCopyStream( io::ZeroCopyInputStream* input, int size); // Parses a protocol buffer contained in a string. Returns true on success. // This function takes a string in the (non-human-readable) binary wire // format, matching the encoding output by MessageLite::SerializeToString(). // If you'd like to convert a human-readable string into a protocol buffer // object, see google::protobuf::TextFormat::ParseFromString(). PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromString(ConstStringParam data); // Like ParseFromString(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromString( ConstStringParam data); // Parse a protocol buffer contained in an array of bytes. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParseFromArray(const void* data, int size); // Like ParseFromArray(), but accepts messages that are missing // required fields. PROTOBUF_ATTRIBUTE_REINITIALIZES bool ParsePartialFromArray(const void* data, int size); // Reads a protocol buffer from the stream and merges it into this // Message. Singular fields read from the what is // already in the Message and repeated fields are appended to those // already present. // // It is the responsibility of the caller to call input->LastTagWas() // (for groups) or input->ConsumedEntireMessage() (for non-groups) after // this returns to verify that the message's end was delimited correctly. // // ParseFromCodedStream() is implemented as Clear() followed by // MergeFromCodedStream(). bool MergeFromCodedStream(io::CodedInputStream* input); // Like MergeFromCodedStream(), but succeeds even if required fields are // missing in the input. // // MergeFromCodedStream() is just implemented as MergePartialFromCodedStream() // followed by IsInitialized(). bool MergePartialFromCodedStream(io::CodedInputStream* input); // Merge a protocol buffer contained in a string. bool MergeFromString(ConstStringParam data); // Serialization --------------------------------------------------- // Methods for serializing in protocol buffer format. Most of these // are just simple wrappers around ByteSize() and SerializeWithCachedSizes(). // Write a protocol buffer of this message to the given output. Returns // false on a write error. If the message is missing required fields, // this may GOOGLE_CHECK-fail. bool SerializeToCodedStream(io::CodedOutputStream* output) const; // Like SerializeToCodedStream(), but allows missing required fields. bool SerializePartialToCodedStream(io::CodedOutputStream* output) const; // Write the message to the given zero-copy output stream. All required // fields must be set. bool SerializeToZeroCopyStream(io::ZeroCopyOutputStream* output) const; // Like SerializeToZeroCopyStream(), but allows missing required fields. bool SerializePartialToZeroCopyStream(io::ZeroCopyOutputStream* output) const; // Serialize the message and store it in the given string. All required // fields must be set. bool SerializeToString(std::string* output) const; // Like SerializeToString(), but allows missing required fields. bool SerializePartialToString(std::string* output) const; // Serialize the message and store it in the given byte array. All required // fields must be set. bool SerializeToArray(void* data, int size) const; // Like SerializeToArray(), but allows missing required fields. bool SerializePartialToArray(void* data, int size) const; // Make a string encoding the message. Is equivalent to calling // SerializeToString() on a string and using that. Returns the empty // string if SerializeToString() would have returned an error. // Note: If you intend to generate many such strings, you may // reduce heap fragmentation by instead re-using the same string // object with calls to SerializeToString(). std::string SerializeAsString() const; // Like SerializeAsString(), but allows missing required fields. std::string SerializePartialAsString() const; // Serialize the message and write it to the given file descriptor. All // required fields must be set. bool SerializeToFileDescriptor(int file_descriptor) const; // Like SerializeToFileDescriptor(), but allows missing required fields. bool SerializePartialToFileDescriptor(int file_descriptor) const; // Serialize the message and write it to the given C++ ostream. All // required fields must be set. bool SerializeToOstream(std::ostream* output) const; // Like SerializeToOstream(), but allows missing required fields. bool SerializePartialToOstream(std::ostream* output) const; // Like SerializeToString(), but appends to the data to the string's // existing contents. All required fields must be set. bool AppendToString(std::string* output) const; // Like AppendToString(), but allows missing required fields. bool AppendPartialToString(std::string* output) const; // Computes the serialized size of the message. This recursively calls // ByteSizeLong() on all embedded messages. // // ByteSizeLong() is generally linear in the number of fields defined for the // proto. virtual size_t ByteSizeLong() const = 0; // Legacy ByteSize() API. PROTOBUF_DEPRECATED_MSG("Please use ByteSizeLong() instead") int ByteSize() const { return internal::ToIntSize(ByteSizeLong()); } // Serializes the message without recomputing the size. The message must not // have changed since the last call to ByteSize(), and the value returned by // ByteSize must be non-negative. Otherwise the results are undefined. void SerializeWithCachedSizes(io::CodedOutputStream* output) const { output->SetCur(_InternalSerialize(output->Cur(), output->EpsCopy())); } // Functions below here are not part of the public interface. It isn't // enforced, but they should be treated as private, and will be private // at some future time. Unfortunately the implementation of the "friend" // keyword in GCC is broken at the moment, but we expect it will be fixed. // Like SerializeWithCachedSizes, but writes directly to *target, returning // a pointer to the byte immediately after the last byte written. "target" // must point at a byte array of at least ByteSize() bytes. Whether to use // deterministic serialization, e.g., maps in sorted order, is determined by // CodedOutputStream::IsDefaultSerializationDeterministic(). uint8_t* SerializeWithCachedSizesToArray(uint8_t* target) const; // Returns the result of the last call to ByteSize(). An embedded message's // size is needed both to serialize it (because embedded messages are // length-delimited) and to compute the outer message's size. Caching // the size avoids computing it multiple times. // // ByteSize() does not automatically use the cached size when available // because this would require invalidating it every time the message was // modified, which would be too hard and expensive. (E.g. if a deeply-nested // sub-message is changed, all of its parents' cached sizes would need to be // invalidated, which is too much work for an otherwise inlined setter // method.) virtual int GetCachedSize() const = 0; virtual const char* _InternalParse(const char* /*ptr*/, internal::ParseContext* /*ctx*/) { return nullptr; } protected: template static T* CreateMaybeMessage(Arena* arena) { return Arena::CreateMaybeMessage(arena); } inline explicit MessageLite(Arena* arena, bool is_message_owned = false) : _internal_metadata_(arena, is_message_owned) {} // Returns the arena, if any, that directly owns this message and its internal // memory (Arena::Own is different in that the arena doesn't directly own the // internal memory). This method is used in proto's implementation for // swapping, moving and setting allocated, for deciding whether the ownership // of this message or its internal memory could be changed. Arena* GetOwningArena() const { return _internal_metadata_.owning_arena(); } // Returns the arena, used for allocating internal objects(e.g., child // messages, etc), or owning incoming objects (e.g., set allocated). Arena* GetArenaForAllocation() const { return _internal_metadata_.arena(); } internal::InternalMetadata _internal_metadata_; public: enum ParseFlags { kMerge = 0, kParse = 1, kMergePartial = 2, kParsePartial = 3, kMergeWithAliasing = 4, kParseWithAliasing = 5, kMergePartialWithAliasing = 6, kParsePartialWithAliasing = 7 }; template bool ParseFrom(const T& input); // Fast path when conditions match (ie. non-deterministic) // uint8_t* _InternalSerialize(uint8_t* ptr) const; virtual uint8_t* _InternalSerialize( uint8_t* ptr, io::EpsCopyOutputStream* stream) const = 0; // Identical to IsInitialized() except that it logs an error message. bool IsInitializedWithErrors() const { if (IsInitialized()) return true; LogInitializationErrorMessage(); return false; } private: // TODO(gerbens) make this a pure abstract function virtual const void* InternalGetTable() const { return NULL; } friend class FastReflectionMessageMutator; friend class FastReflectionStringSetter; friend class Message; friend class Reflection; friend class internal::ExtensionSet; friend class internal::LazyField; friend class internal::SwapFieldHelper; friend class internal::TcParserBase; friend class internal::WeakFieldMap; friend class internal::WireFormatLite; template friend class Arena::InternalHelper; template friend class internal::GenericTypeHandler; void LogInitializationErrorMessage() const; bool MergeFromImpl(io::CodedInputStream* input, ParseFlags parse_flags); GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageLite); }; namespace internal { template bool MergeFromImpl(StringPiece input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(StringPiece input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(StringPiece input, MessageLite* msg, MessageLite::ParseFlags parse_flags); template bool MergeFromImpl(io::ZeroCopyInputStream* input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(io::ZeroCopyInputStream* input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(io::ZeroCopyInputStream* input, MessageLite* msg, MessageLite::ParseFlags parse_flags); struct BoundedZCIS { io::ZeroCopyInputStream* zcis; int limit; }; template bool MergeFromImpl(BoundedZCIS input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(BoundedZCIS input, MessageLite* msg, MessageLite::ParseFlags parse_flags); extern template bool MergeFromImpl(BoundedZCIS input, MessageLite* msg, MessageLite::ParseFlags parse_flags); template struct SourceWrapper; template bool MergeFromImpl(const SourceWrapper& input, MessageLite* msg, MessageLite::ParseFlags parse_flags) { return input.template MergeInto(msg, parse_flags); } } // namespace internal template bool MessageLite::ParseFrom(const T& input) { if (flags & kParse) Clear(); constexpr bool alias = (flags & kMergeWithAliasing) != 0; return internal::MergeFromImpl(input, this, flags); } // =================================================================== // Shutdown support. // Shut down the entire protocol buffers library, deleting all static-duration // objects allocated by the library or by generated .pb.cc files. // // There are two reasons you might want to call this: // * You use a draconian definition of "memory leak" in which you expect // every single malloc() to have a corresponding free(), even for objects // which live until program exit. // * You are writing a dynamically-loaded library which needs to clean up // after itself when the library is unloaded. // // It is safe to call this multiple times. However, it is not safe to use // any other part of the protocol buffers library after // ShutdownProtobufLibrary() has been called. Furthermore this call is not // thread safe, user needs to synchronize multiple calls. PROTOBUF_EXPORT void ShutdownProtobufLibrary(); namespace internal { // Register a function to be called when ShutdownProtocolBuffers() is called. PROTOBUF_EXPORT void OnShutdown(void (*func)()); // Run an arbitrary function on an arg PROTOBUF_EXPORT void OnShutdownRun(void (*f)(const void*), const void* arg); template T* OnShutdownDelete(T* p) { OnShutdownRun([](const void* pp) { delete static_cast(pp); }, p); return p; } } // namespace internal } // namespace protobuf } // namespace google #include #endif // GOOGLE_PROTOBUF_MESSAGE_LITE_H__