類似 nginx 編譯時產生函數鍊錶

#pragma once
typedef int (*pt)(void);
void init_2();

#include <iostream>
#include "common.h"
using namespace std;
static pt next_pt;
extern pt top_pt;
int filter_2()
{
    cout<<"filter_2"<<endl;
    if(next_pt)
        next_pt();
}
static void filter_2_init()
{
    next_pt = top_pt;
    top_pt = filter_2; 
}
void init_2()
{
    filter_2_init();
}

#include <iostream>
#include "common.h"
using namespace std;
static pt next_pt;
pt top_pt;

static int filter_1()
{
    cout<<"filter_1"<<endl;    
    if(next_pt)
        next_pt();
}
static void filter_init()
{
    next_pt = top_pt;
    top_pt = filter_1;
}
void init_1()
{
    filter_init();
}
int main()
{
    init_1();
    init_2();
    top_pt();
    return 0;
}