#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "common.h"
#include "serversignal.h"

static volatile sig_atomic_t graceful=0;

int main(int argc, char *argv[])
{
signal_init();
int max_worker= 5;

int child = 0;
while(!graceful&&!child){
if(max_worker>0){
switch(fork()){
case -1:
return -1;
break;
case 0:
child =1;
break;
default:
printf("child creat\n");
max_worker--;
break;
}
}else{
int status =0;
if( -1 != wait(&status)){
max_worker++;
printf("parent wakeup\n");
}
}
}

if(!child){
printf("quit kill children first\n");
kill(0, SIGINT);
sleep(20);
}else{
sleep(5);
printf("child quit\n");
}

return 0;
}

void server_graceful_set(int g)
{
if(g>0){
g=1;
}else{
g=0;
}
graceful=g;
}
int server_graceful_get()
{
return graceful;
}

#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "serversignal.h"
#include "server.h"

typedef void (*SIG_HANLDER) (int sig);

struct server_signal{
int sig;
SIG_HANLDER handler;
};

static int signal_handler(int sig);

#define SIG_MAP_GEN(sig, hanlder) {sig, hanlder},

#define SIG_MAP(XX)\
{\
XX(SIGINT, signal_handler)\
XX(SIGHUP, signal_handler)\
XX(0, NULL)\
}\

int signal_init()
{
int index =0;
struct server_signal signals[]=SIG_MAP(SIG_MAP_GEN);

while(signals[index].sig != 0){
struct sigaction act;
memset(&act, 0, sizeof(struct sigaction));
act.sa_handler=(signals[index].handler);
sigemptyset(&act.sa_mask);
sigaction(signals[index].sig, &act, NULL);
index++;
}

return 0;
}

static int signal_handler(int sig)
{
int status=0;
switch(sig){
case SIGINT:
server_graceful_set(1);
break;
case SIGHUP:
printf("sighup\n");
break;
case SIGCHLD:
if(server_graceful_get() == 1){
while(wait(&status)>0){};
}
break;
default:
break;
}
return 0;
}

#ifndef COMMON_H_INCLUDED#define COMMON_H_INCLUDED#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <signal.h>#include <sys/socket.h>#include <sys/types.h>#include <string.h>typedef enum {    true =1,    false =0}boolean;enum logmode{    SERVER_LOG_FILE=0,    SERVER_LOG_STDERR};struct server{    enum logmode svlogmode;};#define ASSERT(p)    do{        if(!p){            printf("assert error at %s , %d .\n", __FILE__, __LINE__);        }    }while(0)#endif // COMMON_H_INCLUDED