ubuntu18.04上安装protubuf3.19.4

1、下载protobuf

sudo wget https://github.com/protocolbuffers/protobuf/releases/download/v3.19.4/protobuf-all-3.19.4.tar.gz

2、解压protobuf

sudo tar -zxvf protobuf-all-3.19.4.tar.gz

3、编译安装

 cd protobuf-3.19.4
 sudo ./autogen.sh
 sudo ./configure --prefix=/usr/local  #--prefix指定安装目录||sudo ./configure --prefix=$/usr/local  #--prefix指定安装目录
 sudo make
 sudo make check
 sudo make install

4、配置环境变量和动态连接库
更改环境变量：

 sudo vim /etc/profile

在文件的末尾添加如下的两行: (把bin路径和pkgconfig路径添加到系统PATH)

 export PATH=P A T H : PATH:PATH:/usr/local/bin/
 export PKG_CONFIG_PATH=$/usr/local/lib/pkgconfig/

配置动态链接库
sudo vim /etc/ld.so.conf

/usr/local/protobuf/lib
$/usr/local/lib

更改完成之后ldconfig即可
{
a、在 Vim 编辑器中，移动光标到文件的末尾或你想插入内容的位置。
b、按下 i 键进入插入模式，并输入你想添加的新内容。
c、按下 Esc 键退出插入模式。
d、输入 :wq 命令，保存并退出文件。如果需要仅保存文件而不退出 Vim，可以输入 :w 命令。
}
5、查看是否安装成功
protoc --version
test.proc代码

syntax = "proto3";

package contacts;

message LoginRequest
{
    string name = 1;
    string pwd = 2;
}

编译test.proc

6、执行protobuf

test.proto protoc test.proto --cpp_out=./

main.cppdaima

#include
#include"test.pb.h"
#include
using namespace std;
#include "google/protobuf/io/zero_copy_stream_impl.h"
#include "google/protobuf/text_format.h"

int main()
{
    contacts::LoginRequest tmp;
    tmp.set_name("shengjie");
    tmp.set_pwd("123456");
    string str;
    tmp.SerializeToString(&str);
    cout<<"str:"<<str<<endl;
    return 0;
}

test.pb.c代码

// Generated by the protocol buffer compiler.  DO NOT EDIT!
// source: test.proto

#ifndef GOOGLE_PROTOBUF_INCLUDED_test_2eproto
#define GOOGLE_PROTOBUF_INCLUDED_test_2eproto

#include 
#include 

#include 
#if PROTOBUF_VERSION < 3019000
#error This file was generated by a newer version of protoc which is
#error incompatible with your Protocol Buffer headers. Please update
#error your headers.
#endif
#if 3019004 < PROTOBUF_MIN_PROTOC_VERSION
#error This file was generated by an older version of protoc which is
#error incompatible with your Protocol Buffer headers. Please
#error regenerate this file with a newer version of protoc.
#endif

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include   // IWYU pragma: export
#include   // IWYU pragma: export
#include 
// @@protoc_insertion_point(includes)
#include 
#define PROTOBUF_INTERNAL_EXPORT_test_2eproto
PROTOBUF_NAMESPACE_OPEN
namespace internal {
class AnyMetadata;
}  // namespace internal
PROTOBUF_NAMESPACE_CLOSE

// Internal implementation detail -- do not use these members.
struct TableStruct_test_2eproto {
  static const ::PROTOBUF_NAMESPACE_ID::internal::ParseTableField entries[]
    PROTOBUF_SECTION_VARIABLE(protodesc_cold);
  static const ::PROTOBUF_NAMESPACE_ID::internal::AuxiliaryParseTableField aux[]
    PROTOBUF_SECTION_VARIABLE(protodesc_cold);
  static const ::PROTOBUF_NAMESPACE_ID::internal::ParseTable schema[1]
    PROTOBUF_SECTION_VARIABLE(protodesc_cold);
  static const ::PROTOBUF_NAMESPACE_ID::internal::FieldMetadata field_metadata[];
  static const ::PROTOBUF_NAMESPACE_ID::internal::SerializationTable serialization_table[];
  static const uint32_t offsets[];
};
extern const ::PROTOBUF_NAMESPACE_ID::internal::DescriptorTable descriptor_table_test_2eproto;
namespace contacts {
class LoginRequest;
struct LoginRequestDefaultTypeInternal;
extern LoginRequestDefaultTypeInternal _LoginRequest_default_instance_;
}  // namespace contacts
PROTOBUF_NAMESPACE_OPEN
template<> ::contacts::LoginRequest* Arena::CreateMaybeMessage<::contacts::LoginRequest>(Arena*);
PROTOBUF_NAMESPACE_CLOSE
namespace contacts {

// ===================================================================

class LoginRequest final :
    public ::PROTOBUF_NAMESPACE_ID::Message /* @@protoc_insertion_point(class_definition:contacts.LoginRequest) */ {
 public:
  inline LoginRequest() : LoginRequest(nullptr) {}
  ~LoginRequest() override;
  explicit constexpr LoginRequest(::PROTOBUF_NAMESPACE_ID::internal::ConstantInitialized);

  LoginRequest(const LoginRequest& from);
  LoginRequest(LoginRequest&& from) noexcept
    : LoginRequest() {
    *this = ::std::move(from);
  }

  inline LoginRequest& operator=(const LoginRequest& from) {
    CopyFrom(from);
    return *this;
  }
  inline LoginRequest& operator=(LoginRequest&& from) noexcept {
    if (this == &from) return *this;
    if (GetOwningArena() == from.GetOwningArena()
  #ifdef PROTOBUF_FORCE_COPY_IN_MOVE
        && GetOwningArena() != nullptr
  #endif  // !PROTOBUF_FORCE_COPY_IN_MOVE
    ) {
      InternalSwap(&from);
    } else {
      CopyFrom(from);
    }
    return *this;
  }

  static const ::PROTOBUF_NAMESPACE_ID::Descriptor* descriptor() {
    return GetDescriptor();
  }
  static const ::PROTOBUF_NAMESPACE_ID::Descriptor* GetDescriptor() {
    return default_instance().GetMetadata().descriptor;
  }
  static const ::PROTOBUF_NAMESPACE_ID::Reflection* GetReflection() {
    return default_instance().GetMetadata().reflection;
  }
  static const LoginRequest& default_instance() {
    return *internal_default_instance();
  }
  static inline const LoginRequest* internal_default_instance() {
    return reinterpret_cast<const LoginRequest*>(
               &_LoginRequest_default_instance_);
  }
  static constexpr int kIndexInFileMessages =
    0;

  friend void swap(LoginRequest& a, LoginRequest& b) {
    a.Swap(&b);
  }
  inline void Swap(LoginRequest* other) {
    if (other == this) return;
  #ifdef PROTOBUF_FORCE_COPY_IN_SWAP
    if (GetOwningArena() != nullptr &&
        GetOwningArena() == other->GetOwningArena()) {
   #else  // PROTOBUF_FORCE_COPY_IN_SWAP
    if (GetOwningArena() == other->GetOwningArena()) {
  #endif  // !PROTOBUF_FORCE_COPY_IN_SWAP
      InternalSwap(other);
    } else {
      ::PROTOBUF_NAMESPACE_ID::internal::GenericSwap(this, other);
    }
  }
  void UnsafeArenaSwap(LoginRequest* other) {
    if (other == this) return;
    GOOGLE_DCHECK(GetOwningArena() == other->GetOwningArena());
    InternalSwap(other);
  }

  // implements Message ----------------------------------------------

  LoginRequest* New(::PROTOBUF_NAMESPACE_ID::Arena* arena = nullptr) const final {
    return CreateMaybeMessage<LoginRequest>(arena);
  }
  using ::PROTOBUF_NAMESPACE_ID::Message::CopyFrom;
  void CopyFrom(const LoginRequest& from);
  using ::PROTOBUF_NAMESPACE_ID::Message::MergeFrom;
  void MergeFrom(const LoginRequest& from);
  private:
  static void MergeImpl(::PROTOBUF_NAMESPACE_ID::Message* to, const ::PROTOBUF_NAMESPACE_ID::Message& from);
  public:
  PROTOBUF_ATTRIBUTE_REINITIALIZES void Clear() final;
  bool IsInitialized() const final;

  size_t ByteSizeLong() const final;
  const char* _InternalParse(const char* ptr, ::PROTOBUF_NAMESPACE_ID::internal::ParseContext* ctx) final;
  uint8_t* _InternalSerialize(
      uint8_t* target, ::PROTOBUF_NAMESPACE_ID::io::EpsCopyOutputStream* stream) const final;
  int GetCachedSize() const final { return _cached_size_.Get(); }

  private:
  void SharedCtor();
  void SharedDtor();
  void SetCachedSize(int size) const final;
  void InternalSwap(LoginRequest* other);

  private:
  friend class ::PROTOBUF_NAMESPACE_ID::internal::AnyMetadata;
  static ::PROTOBUF_NAMESPACE_ID::StringPiece FullMessageName() {
    return "contacts.LoginRequest";
  }
  protected:
  explicit LoginRequest(::PROTOBUF_NAMESPACE_ID::Arena* arena,
                       bool is_message_owned = false);
  private:
  static void ArenaDtor(void* object);
  inline void RegisterArenaDtor(::PROTOBUF_NAMESPACE_ID::Arena* arena);
  public:

  static const ClassData _class_data_;
  const ::PROTOBUF_NAMESPACE_ID::Message::ClassData*GetClassData() const final;

  ::PROTOBUF_NAMESPACE_ID::Metadata GetMetadata() const final;

  // nested types ----------------------------------------------------

  // accessors -------------------------------------------------------

  enum : int {
    kNameFieldNumber = 1,
    kPwdFieldNumber = 2,
  };
  // string name = 1;
  void clear_name();
  const std::string& name() const;
  template <typename ArgT0 = const std::string&, typename... ArgT>
  void set_name(ArgT0&& arg0, ArgT... args);
  std::string* mutable_name();
  PROTOBUF_NODISCARD std::string* release_name();
  void set_allocated_name(std::string* name);
  private:
  const std::string& _internal_name() const;
  inline PROTOBUF_ALWAYS_INLINE void _internal_set_name(const std::string& value);
  std::string* _internal_mutable_name();
  public:

  // string pwd = 2;
  void clear_pwd();
  const std::string& pwd() const;
  template <typename ArgT0 = const std::string&, typename... ArgT>
  void set_pwd(ArgT0&& arg0, ArgT... args);
  std::string* mutable_pwd();
  PROTOBUF_NODISCARD std::string* release_pwd();
  void set_allocated_pwd(std::string* pwd);
  private:
  const std::string& _internal_pwd() const;
  inline PROTOBUF_ALWAYS_INLINE void _internal_set_pwd(const std::string& value);
  std::string* _internal_mutable_pwd();
  public:

  // @@protoc_insertion_point(class_scope:contacts.LoginRequest)
 private:
  class _Internal;

  template <typename T> friend class ::PROTOBUF_NAMESPACE_ID::Arena::InternalHelper;
  typedef void InternalArenaConstructable_;
  typedef void DestructorSkippable_;
  ::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr name_;
  ::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr pwd_;
  mutable ::PROTOBUF_NAMESPACE_ID::internal::CachedSize _cached_size_;
  friend struct ::TableStruct_test_2eproto;
};
// ===================================================================


// ===================================================================

#ifdef __GNUC__
  #pragma GCC diagnostic push
  #pragma GCC diagnostic ignored "-Wstrict-aliasing"
#endif  // __GNUC__
// LoginRequest

// string name = 1;
inline void LoginRequest::clear_name() {
  name_.ClearToEmpty();
}
inline const std::string& LoginRequest::name() const {
  // @@protoc_insertion_point(field_get:contacts.LoginRequest.name)
  return _internal_name();
}
template <typename ArgT0, typename... ArgT>
inline PROTOBUF_ALWAYS_INLINE
void LoginRequest::set_name(ArgT0&& arg0, ArgT... args) {
 
 name_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, static_cast<ArgT0 &&>(arg0), args..., GetArenaForAllocation());
  // @@protoc_insertion_point(field_set:contacts.LoginRequest.name)
}
inline std::string* LoginRequest::mutable_name() {
  std::string* _s = _internal_mutable_name();
  // @@protoc_insertion_point(field_mutable:contacts.LoginRequest.name)
  return _s;
}
inline const std::string& LoginRequest::_internal_name() const {
  return name_.Get();
}
inline void LoginRequest::_internal_set_name(const std::string& value) {
  
  name_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, value, GetArenaForAllocation());
}
inline std::string* LoginRequest::_internal_mutable_name() {
  
  return name_.Mutable(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, GetArenaForAllocation());
}
inline std::string* LoginRequest::release_name() {
  // @@protoc_insertion_point(field_release:contacts.LoginRequest.name)
  return name_.Release(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), GetArenaForAllocation());
}
inline void LoginRequest::set_allocated_name(std::string* name) {
  if (name != nullptr) {
    
  } else {
    
  }
  name_.SetAllocated(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), name,
      GetArenaForAllocation());
#ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
  if (name_.IsDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited())) {
    name_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
  }
#endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
  // @@protoc_insertion_point(field_set_allocated:contacts.LoginRequest.name)
}

// string pwd = 2;
inline void LoginRequest::clear_pwd() {
  pwd_.ClearToEmpty();
}
inline const std::string& LoginRequest::pwd() const {
  // @@protoc_insertion_point(field_get:contacts.LoginRequest.pwd)
  return _internal_pwd();
}
template <typename ArgT0, typename... ArgT>
inline PROTOBUF_ALWAYS_INLINE
void LoginRequest::set_pwd(ArgT0&& arg0, ArgT... args) {
 
 pwd_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, static_cast<ArgT0 &&>(arg0), args..., GetArenaForAllocation());
  // @@protoc_insertion_point(field_set:contacts.LoginRequest.pwd)
}
inline std::string* LoginRequest::mutable_pwd() {
  std::string* _s = _internal_mutable_pwd();
  // @@protoc_insertion_point(field_mutable:contacts.LoginRequest.pwd)
  return _s;
}
inline const std::string& LoginRequest::_internal_pwd() const {
  return pwd_.Get();
}
inline void LoginRequest::_internal_set_pwd(const std::string& value) {
  
  pwd_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, value, GetArenaForAllocation());
}
inline std::string* LoginRequest::_internal_mutable_pwd() {
  
  return pwd_.Mutable(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, GetArenaForAllocation());
}
inline std::string* LoginRequest::release_pwd() {
  // @@protoc_insertion_point(field_release:contacts.LoginRequest.pwd)
  return pwd_.Release(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), GetArenaForAllocation());
}
inline void LoginRequest::set_allocated_pwd(std::string* pwd) {
  if (pwd != nullptr) {
    
  } else {
    
  }
  pwd_.SetAllocated(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), pwd,
      GetArenaForAllocation());
#ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
  if (pwd_.IsDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited())) {
    pwd_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
  }
#endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
  // @@protoc_insertion_point(field_set_allocated:contacts.LoginRequest.pwd)
}

#ifdef __GNUC__
  #pragma GCC diagnostic pop
#endif  // __GNUC__

// @@protoc_insertion_point(namespace_scope)

}  // namespace contacts

// @@protoc_insertion_point(global_scope)

#include 
#endif  // GOOGLE_PROTOBUF_INCLUDED_GOOGLE_PROTOBUF_INCLUDED_test_2eproto

test.pb.ccd代码

// Generated by the protocol buffer compiler.  DO NOT EDIT!
// source: test.proto

#include "test.pb.h"

#include 

#include 
#include 
#include 
#include 
#include 
#include 
#include 
// @@protoc_insertion_point(includes)
#include 

PROTOBUF_PRAGMA_INIT_SEG
namespace contacts {
constexpr LoginRequest::LoginRequest(
  ::PROTOBUF_NAMESPACE_ID::internal::ConstantInitialized)
  : name_(&::PROTOBUF_NAMESPACE_ID::internal::fixed_address_empty_string)
  , pwd_(&::PROTOBUF_NAMESPACE_ID::internal::fixed_address_empty_string){}
struct LoginRequestDefaultTypeInternal {
  constexpr LoginRequestDefaultTypeInternal()
    : _instance(::PROTOBUF_NAMESPACE_ID::internal::ConstantInitialized{}) {}
  ~LoginRequestDefaultTypeInternal() {}
  union {
    LoginRequest _instance;
  };
};
PROTOBUF_ATTRIBUTE_NO_DESTROY PROTOBUF_CONSTINIT LoginRequestDefaultTypeInternal _LoginRequest_default_instance_;
}  // namespace contacts
static ::PROTOBUF_NAMESPACE_ID::Metadata file_level_metadata_test_2eproto[1];
static constexpr ::PROTOBUF_NAMESPACE_ID::EnumDescriptor const** file_level_enum_descriptors_test_2eproto = nullptr;
static constexpr ::PROTOBUF_NAMESPACE_ID::ServiceDescriptor const** file_level_service_descriptors_test_2eproto = nullptr;

const uint32_t TableStruct_test_2eproto::offsets[] PROTOBUF_SECTION_VARIABLE(protodesc_cold) = {
  ~0u,  // no _has_bits_
  PROTOBUF_FIELD_OFFSET(::contacts::LoginRequest, _internal_metadata_),
  ~0u,  // no _extensions_
  ~0u,  // no _oneof_case_
  ~0u,  // no _weak_field_map_
  ~0u,  // no _inlined_string_donated_
  PROTOBUF_FIELD_OFFSET(::contacts::LoginRequest, name_),
  PROTOBUF_FIELD_OFFSET(::contacts::LoginRequest, pwd_),
};
static const ::PROTOBUF_NAMESPACE_ID::internal::MigrationSchema schemas[] PROTOBUF_SECTION_VARIABLE(protodesc_cold) = {
  { 0, -1, -1, sizeof(::contacts::LoginRequest)},
};

static ::PROTOBUF_NAMESPACE_ID::Message const * const file_default_instances[] = {
  reinterpret_cast<const ::PROTOBUF_NAMESPACE_ID::Message*>(&::contacts::_LoginRequest_default_instance_),
};

const char descriptor_table_protodef_test_2eproto[] PROTOBUF_SECTION_VARIABLE(protodesc_cold) =
  "\n\ntest.proto\022\010contacts\")\n\014LoginRequest\022\014"
  "\n\004name\030\001 \001(\t\022\013\n\003pwd\030\002 \001(\tb\006proto3"
  ;
static ::PROTOBUF_NAMESPACE_ID::internal::once_flag descriptor_table_test_2eproto_once;
const ::PROTOBUF_NAMESPACE_ID::internal::DescriptorTable descriptor_table_test_2eproto = {
  false, false, 73, descriptor_table_protodef_test_2eproto, "test.proto", 
  &descriptor_table_test_2eproto_once, nullptr, 0, 1,
  schemas, file_default_instances, TableStruct_test_2eproto::offsets,
  file_level_metadata_test_2eproto, file_level_enum_descriptors_test_2eproto, file_level_service_descriptors_test_2eproto,
};
PROTOBUF_ATTRIBUTE_WEAK const ::PROTOBUF_NAMESPACE_ID::internal::DescriptorTable* descriptor_table_test_2eproto_getter() {
  return &descriptor_table_test_2eproto;
}

// Force running AddDescriptors() at dynamic initialization time.
PROTOBUF_ATTRIBUTE_INIT_PRIORITY static ::PROTOBUF_NAMESPACE_ID::internal::AddDescriptorsRunner dynamic_init_dummy_test_2eproto(&descriptor_table_test_2eproto);
namespace contacts {

// ===================================================================

class LoginRequest::_Internal {
 public:
};

LoginRequest::LoginRequest(::PROTOBUF_NAMESPACE_ID::Arena* arena,
                         bool is_message_owned)
  : ::PROTOBUF_NAMESPACE_ID::Message(arena, is_message_owned) {
  SharedCtor();
  if (!is_message_owned) {
    RegisterArenaDtor(arena);
  }
  // @@protoc_insertion_point(arena_constructor:contacts.LoginRequest)
}
LoginRequest::LoginRequest(const LoginRequest& from)
  : ::PROTOBUF_NAMESPACE_ID::Message() {
  _internal_metadata_.MergeFrom<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>(from._internal_metadata_);
  name_.UnsafeSetDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
  #ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
    name_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
  #endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
  if (!from._internal_name().empty()) {
    name_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, from._internal_name(), 
      GetArenaForAllocation());
  }
  pwd_.UnsafeSetDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
  #ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
    pwd_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
  #endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
  if (!from._internal_pwd().empty()) {
    pwd_.Set(::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::EmptyDefault{}, from._internal_pwd(), 
      GetArenaForAllocation());
  }
  // @@protoc_insertion_point(copy_constructor:contacts.LoginRequest)
}

inline void LoginRequest::SharedCtor() {
name_.UnsafeSetDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
#ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
  name_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
#endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
pwd_.UnsafeSetDefault(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
#ifdef PROTOBUF_FORCE_COPY_DEFAULT_STRING
  pwd_.Set(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(), "", GetArenaForAllocation());
#endif // PROTOBUF_FORCE_COPY_DEFAULT_STRING
}

LoginRequest::~LoginRequest() {
  // @@protoc_insertion_point(destructor:contacts.LoginRequest)
  if (GetArenaForAllocation() != nullptr) return;
  SharedDtor();
  _internal_metadata_.Delete<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>();
}

inline void LoginRequest::SharedDtor() {
  GOOGLE_DCHECK(GetArenaForAllocation() == nullptr);
  name_.DestroyNoArena(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
  pwd_.DestroyNoArena(&::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited());
}

void LoginRequest::ArenaDtor(void* object) {
  LoginRequest* _this = reinterpret_cast< LoginRequest* >(object);
  (void)_this;
}
void LoginRequest::RegisterArenaDtor(::PROTOBUF_NAMESPACE_ID::Arena*) {
}
void LoginRequest::SetCachedSize(int size) const {
  _cached_size_.Set(size);
}

void LoginRequest::Clear() {
// @@protoc_insertion_point(message_clear_start:contacts.LoginRequest)
  uint32_t cached_has_bits = 0;
  // Prevent compiler warnings about cached_has_bits being unused
  (void) cached_has_bits;

  name_.ClearToEmpty();
  pwd_.ClearToEmpty();
  _internal_metadata_.Clear<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>();
}

const char* LoginRequest::_InternalParse(const char* ptr, ::PROTOBUF_NAMESPACE_ID::internal::ParseContext* ctx) {
#define CHK_(x) if (PROTOBUF_PREDICT_FALSE(!(x))) goto failure
  while (!ctx->Done(&ptr)) {
    uint32_t tag;
    ptr = ::PROTOBUF_NAMESPACE_ID::internal::ReadTag(ptr, &tag);
    switch (tag >> 3) {
      // string name = 1;
      case 1:
        if (PROTOBUF_PREDICT_TRUE(static_cast<uint8_t>(tag) == 10)) {
          auto str = _internal_mutable_name();
          ptr = ::PROTOBUF_NAMESPACE_ID::internal::InlineGreedyStringParser(str, ptr, ctx);
          CHK_(::PROTOBUF_NAMESPACE_ID::internal::VerifyUTF8(str, "contacts.LoginRequest.name"));
          CHK_(ptr);
        } else
          goto handle_unusual;
        continue;
      // string pwd = 2;
      case 2:
        if (PROTOBUF_PREDICT_TRUE(static_cast<uint8_t>(tag) == 18)) {
          auto str = _internal_mutable_pwd();
          ptr = ::PROTOBUF_NAMESPACE_ID::internal::InlineGreedyStringParser(str, ptr, ctx);
          CHK_(::PROTOBUF_NAMESPACE_ID::internal::VerifyUTF8(str, "contacts.LoginRequest.pwd"));
          CHK_(ptr);
        } else
          goto handle_unusual;
        continue;
      default:
        goto handle_unusual;
    }  // switch
  handle_unusual:
    if ((tag == 0) || ((tag & 7) == 4)) {
      CHK_(ptr);
      ctx->SetLastTag(tag);
      goto message_done;
    }
    ptr = UnknownFieldParse(
        tag,
        _internal_metadata_.mutable_unknown_fields<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>(),
        ptr, ctx);
    CHK_(ptr != nullptr);
  }  // while
message_done:
  return ptr;
failure:
  ptr = nullptr;
  goto message_done;
#undef CHK_
}

uint8_t* LoginRequest::_InternalSerialize(
    uint8_t* target, ::PROTOBUF_NAMESPACE_ID::io::EpsCopyOutputStream* stream) const {
  // @@protoc_insertion_point(serialize_to_array_start:contacts.LoginRequest)
  uint32_t cached_has_bits = 0;
  (void) cached_has_bits;

  // string name = 1;
  if (!this->_internal_name().empty()) {
    ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::VerifyUtf8String(
      this->_internal_name().data(), static_cast<int>(this->_internal_name().length()),
      ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::SERIALIZE,
      "contacts.LoginRequest.name");
    target = stream->WriteStringMaybeAliased(
        1, this->_internal_name(), target);
  }

  // string pwd = 2;
  if (!this->_internal_pwd().empty()) {
    ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::VerifyUtf8String(
      this->_internal_pwd().data(), static_cast<int>(this->_internal_pwd().length()),
      ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::SERIALIZE,
      "contacts.LoginRequest.pwd");
    target = stream->WriteStringMaybeAliased(
        2, this->_internal_pwd(), target);
  }

  if (PROTOBUF_PREDICT_FALSE(_internal_metadata_.have_unknown_fields())) {
    target = ::PROTOBUF_NAMESPACE_ID::internal::WireFormat::InternalSerializeUnknownFieldsToArray(
        _internal_metadata_.unknown_fields<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>(::PROTOBUF_NAMESPACE_ID::UnknownFieldSet::default_instance), target, stream);
  }
  // @@protoc_insertion_point(serialize_to_array_end:contacts.LoginRequest)
  return target;
}

size_t LoginRequest::ByteSizeLong() const {
// @@protoc_insertion_point(message_byte_size_start:contacts.LoginRequest)
  size_t total_size = 0;

  uint32_t cached_has_bits = 0;
  // Prevent compiler warnings about cached_has_bits being unused
  (void) cached_has_bits;

  // string name = 1;
  if (!this->_internal_name().empty()) {
    total_size += 1 +
      ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::StringSize(
        this->_internal_name());
  }

  // string pwd = 2;
  if (!this->_internal_pwd().empty()) {
    total_size += 1 +
      ::PROTOBUF_NAMESPACE_ID::internal::WireFormatLite::StringSize(
        this->_internal_pwd());
  }

  return MaybeComputeUnknownFieldsSize(total_size, &_cached_size_);
}

const ::PROTOBUF_NAMESPACE_ID::Message::ClassData LoginRequest::_class_data_ = {
    ::PROTOBUF_NAMESPACE_ID::Message::CopyWithSizeCheck,
    LoginRequest::MergeImpl
};
const ::PROTOBUF_NAMESPACE_ID::Message::ClassData*LoginRequest::GetClassData() const { return &_class_data_; }

void LoginRequest::MergeImpl(::PROTOBUF_NAMESPACE_ID::Message* to,
                      const ::PROTOBUF_NAMESPACE_ID::Message& from) {
  static_cast<LoginRequest *>(to)->MergeFrom(
      static_cast<const LoginRequest &>(from));
}


void LoginRequest::MergeFrom(const LoginRequest& from) {
// @@protoc_insertion_point(class_specific_merge_from_start:contacts.LoginRequest)
  GOOGLE_DCHECK_NE(&from, this);
  uint32_t cached_has_bits = 0;
  (void) cached_has_bits;

  if (!from._internal_name().empty()) {
    _internal_set_name(from._internal_name());
  }
  if (!from._internal_pwd().empty()) {
    _internal_set_pwd(from._internal_pwd());
  }
  _internal_metadata_.MergeFrom<::PROTOBUF_NAMESPACE_ID::UnknownFieldSet>(from._internal_metadata_);
}

void LoginRequest::CopyFrom(const LoginRequest& from) {
// @@protoc_insertion_point(class_specific_copy_from_start:contacts.LoginRequest)
  if (&from == this) return;
  Clear();
  MergeFrom(from);
}

bool LoginRequest::IsInitialized() const {
  return true;
}

void LoginRequest::InternalSwap(LoginRequest* other) {
  using std::swap;
  auto* lhs_arena = GetArenaForAllocation();
  auto* rhs_arena = other->GetArenaForAllocation();
  _internal_metadata_.InternalSwap(&other->_internal_metadata_);
  ::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::InternalSwap(
      &::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(),
      &name_, lhs_arena,
      &other->name_, rhs_arena
  );
  ::PROTOBUF_NAMESPACE_ID::internal::ArenaStringPtr::InternalSwap(
      &::PROTOBUF_NAMESPACE_ID::internal::GetEmptyStringAlreadyInited(),
      &pwd_, lhs_arena,
      &other->pwd_, rhs_arena
  );
}

::PROTOBUF_NAMESPACE_ID::Metadata LoginRequest::GetMetadata() const {
  return ::PROTOBUF_NAMESPACE_ID::internal::AssignDescriptors(
      &descriptor_table_test_2eproto_getter, &descriptor_table_test_2eproto_once,
      file_level_metadata_test_2eproto[0]);
}

// @@protoc_insertion_point(namespace_scope)
}  // namespace contacts
PROTOBUF_NAMESPACE_OPEN
template<> PROTOBUF_NOINLINE ::contacts::LoginRequest* Arena::CreateMaybeMessage< ::contacts::LoginRequest >(Arena* arena) {
  return Arena::CreateMessageInternal< ::contacts::LoginRequest >(arena);
}
PROTOBUF_NAMESPACE_CLOSE

// @@protoc_insertion_point(global_scope)
#include 

main.cpp test.proto
编译：test.proto protoc test.proto --cpp_out=./
g++ main.cpp test.pb.cc -I/usr/local/include -L/usr/local/lib -lprotobuf 

7、执行main.cpp代码

g++ main.cpp test.pb.cc -I/usr/local/include -L/usr/local/lib -lprotobuf 

8、查看ubuntu的版本：lsb_release -a，cat /etc/issue
9、查看内核版本：uname -r