c++ 在使用动态库时，是否有更好的方法来定义多个函数定义？

7gyucuyw 于 2024-01-09 发布在其他

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下面的代码清单工作得很好--但由于我仍在尝试C++沃茨，我想知道是否有更好的--更通用的--方法来定义每个函数定义。
我计划使用动态库作为一种游戏插件系统，并且正在考虑使用类似std：：map<functionName，functionPtr>类型的安排来跟踪每个插件可用的每个函数。但是我不知道如何实现每个函数定义的不同。

#include <cassert>
#include <iostream>
#include <dlfcn.h>
//
// How could I encapsulate these in a consistent way?
//
typedef bool        (*logfileOpen_type)(const std::string &newFileName);    // logfile_open
typedef void        (*logfileWrite_type)(const std::string &logText);       //logfile_write
typedef void        (*logfileClose_type)();                //logfile_close
typedef std::string (*logfileError_type)();                //logFile_getLastError
typedef bool        (*logfileActive_type)();               //logFile_enabled
int main()
{
    // Load a dynamic plugin.
    auto libHandle = dlopen("./libPluginLogfile.so", RTLD_LAZY);
    assert(libHandle != nullptr);
    if (libHandle != nullptr)
        printf("INFO: Plugin successfully loaded.\n");
    else
    {
        printf("ERROR: Plugin failed to load.\n");
        exit(-1);
    }
    // Get the address of the desired function
    auto openFunction = (logfileOpen_type) dlsym(libHandle, "logFile_open");
    if (openFunction == nullptr)
        printf("Unable to find function [ %s ] [ %s ]\n", "logFile_open", dlerror());
    auto writeFunction = (logfileWrite_type) dlsym(libHandle, "logFile_write");
    if (writeFunction == nullptr)
        printf("Unable to find function [ %s ] [ %s ]\n", "logFile_write", dlerror());
    auto closeFunction = (logfileClose_type) dlsym(libHandle, "logFile_close");
    if (closeFunction == nullptr)
        printf("Unable to find function [ %s ] [ %s ]\n", "logFile_close", dlerror());
    auto getErrorFunction = (logfileError_type) dlsym(libHandle, "logFile_getLastError");
    if (getErrorFunction == nullptr)
        printf("Unable to find function [ %s ] [ %s ]\n", "logFile_getLastError", dlerror());
    auto getEnabledFunction = (logfileActive_type) dlsym(libHandle, "logFile_enabled");
    if (getEnabledFunction == nullptr)
        printf("Unable to find function [ %s ] [ %s ]\n", "logFile_enabled", dlerror());
    openFunction("logfile.log");
    writeFunction("Writing to the logfile.");
    writeFunction(".. and a second line.");
    closeFunction();
    dlclose(libHandle);
    std::cout << "INFO: Plugin Unloaded." << std::endl;
    return 0;
}