message_lite.h | Explore in Territory

// 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: [email protected] (Wink Saville),
//          [email protected] (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 <climits>
#include <string>

#include <google/protobuf/stubs/common.h>
#include <google/protobuf/stubs/logging.h>
#include <google/protobuf/io/coded_stream.h>
#include <google/protobuf/arena.h>
#include <google/protobuf/stubs/once.h>
#include <google/protobuf/port.h>
#include <google/protobuf/stubs/strutil.h>
#include <google/protobuf/explicitly_constructed.h>
#include <google/protobuf/metadata_lite.h>
#include <google/protobuf/stubs/hash.h>  // TODO(b/211442718): cleanup

// clang-format off
#include <google/protobuf/port_def.inc>
// clang-format on

#ifdef SWIG
#error "You cannot SWIG proto headers"
#endif

namespace google {
namespace protobuf {

template <typename T>
class RepeatedPtrField;

class FastReflectionMessageMutator;
class FastReflectionStringSetter;
class Reflection;

namespace io {

class CodedInputStream;
class CodedOutputStream;
class ZeroCopyInputStream;
class ZeroCopyOutputStream;

}  // namespace io
namespace internal {

class SwapFieldHelper;

// See parse_context.h for explanation
class ParseContext;

class ExtensionSet;
class LazyField;
class RepeatedPtrFieldBase;
class TcParser;
class WireFormatLite;
class WeakFieldMap;

template <typename Type>
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) { … }

// 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) { … }

// 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) { … }

// Default empty string object. Don't use this directly. Instead, call
// GetEmptyString() to get the reference. This empty string is aligned with a
// minimum alignment of 8 bytes to match the requirement of ArenaStringPtr.
PROTOBUF_EXPORT extern ExplicitlyConstructedArenaString
    fixed_address_empty_string;


PROTOBUF_EXPORT constexpr const std::string& GetEmptyStringAlreadyInited() { … }

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 { … };

namespace internal {

template <bool alias>
bool MergeFromImpl(StringPiece input, MessageLite* msg,
                   MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<false>(StringPiece input,
                                          MessageLite* msg,
                                          MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<true>(StringPiece input,
                                         MessageLite* msg,
                                         MessageLite::ParseFlags parse_flags);

template <bool alias>
bool MergeFromImpl(io::ZeroCopyInputStream* input, MessageLite* msg,
                   MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<false>(io::ZeroCopyInputStream* input,
                                          MessageLite* msg,
                                          MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<true>(io::ZeroCopyInputStream* input,
                                         MessageLite* msg,
                                         MessageLite::ParseFlags parse_flags);

struct BoundedZCIS { … };

template <bool alias>
bool MergeFromImpl(BoundedZCIS input, MessageLite* msg,
                   MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<false>(BoundedZCIS input, MessageLite* msg,
                                          MessageLite::ParseFlags parse_flags);
extern template bool MergeFromImpl<true>(BoundedZCIS input, MessageLite* msg,
                                         MessageLite::ParseFlags parse_flags);

template <typename T>
struct SourceWrapper;

template <bool alias, typename T>
bool MergeFromImpl(const SourceWrapper<T>& input, MessageLite* msg,
                   MessageLite::ParseFlags parse_flags) { … }

}  // namespace internal

template <MessageLite::ParseFlags flags, typename T>
bool MessageLite::ParseFrom(const T& input) { … }

// ===================================================================
// 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 <typename T>
T* OnShutdownDelete(T* p) { … }

}  // namespace internal
}  // namespace protobuf
}  // namespace google

#include <google/protobuf/port_undef.inc>

#endif  // GOOGLE_PROTOBUF_MESSAGE_LITE_H__
chromium/third_party/protobuf/src/google/protobuf/message_lite.h
