对 boost::serialization 的未定义引用

Question

我正在尝试使用 boost::asio 创建一些具有序列化结构的简单服务器。但是，在我的项目中尝试使用 boost::archives 时，我遇到了一些链接器错误。我得到很多未定义的引用。你能帮我找出错误吗？

src/libserver.a(session.cpp.o): In function `boost::archive::text_iarchive::text_iarchive(std::istream&, unsigned int)':
session.cpp:(.text._ZN5boost7archive13text_iarchiveC2ERSij[_ZN5boost7archive13text_iarchiveC5ERSij]+0x25): undefined reference to `boost::archive::text_iarchive_impl<boost::archive::text_iarchive>::text_iarchive_impl(std::istream&, unsigned int)'

我的项目结构如下：

.
├── CMakeLists.txt
├── main.cpp
└── src
    ├── CMakeLists.txt
    ├── server.cpp
    ├── server.hpp
    ├── session.cpp
    └── session.hpp

我的根 CMakeLists.txt

cmake_minimum_required(VERSION 3.5)
project(mainServer)

set(Boost_USE_STATIC_LIBS OFF)
set(Boost_USE_MULTITHREADED ON)
set(Boost_USE_STATIC_RUNTIME OFF)

add_subdirectory(src)

find_package(Boost 1.65.1.0 REQUIRED system)

if(Boost_FOUND)
    include_directories(${Boost_INCLUDE_DIRS})
    add_executable(mainServer main.cpp)
    target_link_libraries(mainServer ${Boost_LIBRARIES})
    target_link_libraries(mainServer server)
endif()

还有我的 src CMakeLists.txt

add_library(
    server
    server.cpp
    session.cpp
)

set_target_properties(server PROPERTIES LINKER_LANGUAGE CXX)
target_include_directories(server PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")

以及在 session.hpp 中产生链接错误的代码

#pragma once

#include <boost/asio.hpp>
#include <string>
#include <deque>
#include <memory>
#include <message/message.hpp>
#include <boost/tuple/tuple.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <boost/bind/bind.hpp>

class Session : public std::enable_shared_from_this<Session>
{
public:
    Session(boost::asio::ip::tcp::socket socket) : socket(std::move(socket))
    {
    }

    void run();
    void printMessage(const boost::system::error_code &e);
    boost::asio::streambuf stream_buf;

private:
    boost::asio::ip::tcp::socket socket;
    common::message::Message msg;

    template <typename Handler>
    void readMsg(Handler handler)
    {
        void (Session::*f)(
            const boost::system::error_code &,
            common::message::Message &, boost::tuple<Handler>) = &Session::handle_read_header<common::message::Message, Handler>;
        boost::asio::async_read(socket, boost::asio::buffer(inboundHeader),
                                boost::bind(f,
                                            this, boost::asio::placeholders::error, boost::ref(msg),
                                            boost::make_tuple(handler)));
    }

    template <typename T, typename Handler>
    void handle_read_header(const boost::system::error_code &e,
                            T &t, boost::tuple<Handler> handler)
    {
        if (e)
        {
            boost::get<0>(handler)(e);
        }
        else
        {
            std::istringstream is(std::string(inboundHeader, headerLength));
            std::size_t inbound_data_size = 0;
            if (!(is >> std::hex >> inbound_data_size))
            {
                boost::system::error_code error(boost::asio::error::invalid_argument);
                boost::get<0>(handler)(error);
                return;
            }

            inboundData.resize(inbound_data_size);
            void (Session::*f)(
                const boost::system::error_code &,
                T &, boost::tuple<Handler>) = &Session::handle_read_data<T, Handler>;
            boost::asio::async_read(socket, boost::asio::buffer(inboundData),
                                    boost::bind(f, this,
                                                boost::asio::placeholders::error, boost::ref(t), handler));
        }
    }

    template <typename T, typename Handler>
    void handle_read_data(const boost::system::error_code &e,
                          T &t, boost::tuple<Handler> handler)
    {
        if (e)
        {
            boost::get<0>(handler)(e);
        }
        else
        {
            try
            {
                std::string archive_data(&inboundData[0], inboundData.size());
                std::istringstream archive_stream(archive_data);
                boost::archive::text_iarchive archive(archive_stream);
                archive >> t;
            }
            catch (std::exception &e)
            {
                boost::system::error_code error(boost::asio::error::invalid_argument);
                boost::get<0>(handler)(error);
                return;
            }
            boost::get<0>(handler)(e);
        }
    }

    static const size_t headerLength{8};
    std::string outboundHeader;
    std::string outboundData;
    char inboundHeader[headerLength];
    std::vector<char> inboundData;
};

Answer 1

序列化是一个预编译库，因此您必须将它包含在您的 find 命令中： find_package(Boost 1.65.1.0 REQUIRED system serialization)

只搜索 Boost 和 Boost::system 只会包含 boost 和系统库的头文件，而不包含序列化库的二进制文件。 它编译的原因是，序列化标头包含在 Boost::boost 中，但它无法链接，因为您没有链接到实现。