如何使一个函数接受其他函数作为参数(没有已知参数) [英] How to make a function which receive other function as param (with no known parameters)

问题描述

以前，我问过如何用C语言编写一个将函数作为参数接收的函数.我得到了一个答案链接到问题，但是此解决方案基于参数函数的参数.我的意思是:

Previously I asked How to make a function which receive a function as param in C language. I get an answer Link to the question but this solution is based on the parameters of argument's function. I mean:

int functionToPassAsParameter (int arg1, int arg2){
    // do something
}

int functionWhichReceiveFunction (int (*f)(), int arg1, int arg2){
    // do something
    f(arg1, arg2);
    // do something
}

// How to call the function
functionWhichReceiveFunction (&functionToPassAsParameter, 1, 2);

我想要类似的东西

int functionToPassAsParameter (int arg1, int arg2){
    // do something
}

int functionWhichReceiveFunction ( f() ){
    // do something
    f();
    // do something
}

// How to call the function
functionWhichReceiveFunction ( functionToPassAsParameter(arg1, arg2) );

因此，当我调用函数时，我传递了正确的参数，但是当我定义接收其他函数的函数时，我没有指定要发送给它的参数.这有可能吗?

So, when I call the function, I pass the correctly params but when I define the function which receive the other function I do not specify which params I will send to it. Is that possible to make?

---

我想实现将任何功能传递给functionWhichReceiveFunction.像这样:

---

EDIT 1: I wanna achieve pass any function to functionWhichReceiveFunction. Something like:

int function_a (int param1, int param2) { /* Do something */ };
void function_b (char *arg1) { /* Do something */ };

// Call the function with two differents functions regardless return type nor params
int x = functionWhichReceiveFunction ( function_a(param1, param2) );
functionWhichReceiveFunction ( function_b(arg1) );

推荐答案

定义要传递的函数，以使用void *作为参数.这样，调用给定函数的函数就不需要了解有关参数的任何特定信息:

Define the function to be passed to take a void * as a parameter. That way the function that calls the given function doesn't need to know anything specific about the parameters:

struct params1 {
   int arg1;
   int arg2;
};

struct params2 {
   char *arg1;
   char *arg2;
};

int functionToPassAsParameter (void *param){
    struct params1 *args = params;
    // do something
}

int otherFunctionToPassAsParameter (void *param){
    struct params2 *args = params;
    // do something
}

int functionWhichReceiveFunction (int (*f)(void *), void *args) {
    // do something
    f(args);
    // do something
}

struct params1 p1 = { 1, 2 };
functionWhichReceiveFunction (&functionToPassAsParameter, &p1);
struct params2 p2 = { "abc", "def" };
functionWhichReceiveFunction (&otherFunctionToPassAsParameter, &p2);

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