#include "fcgi_stdio.h"
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>

static int busy = 0; // busy processing request?
static int end_program = 0; // flag to terminate process

// Handle termination signal by setting flag
void signal_handler(int sig) {
    if (sig == SIGTERM) {
        // if not busy, exit now. If busy, exit when the main loop ends
        if (busy == 0) exit(0);
        end_program = 1;
        return;
    }
}

// Main FCGI process
void main(void) {
    // Set termination signal handler
    struct sigaction psa;
    memset (&psa, 0, sizeof (psa));
    psa.sa_handler = signal_handler;
    sigaction(SIGTERM, &psa, NULL);


    // main FCGI request-processing loop, simply display Hello world page each time
    while (FCGI_Accept() >= 0)   {
        busy = 1; // program busy now

        printf("Content-type: text/html\r\n"
           "\r\n"
           "<title>Hello World!</title>"
           "<h1>Hello there!</h1>");

        busy = 0; // program no longer busy
        // exit graceful at the end of request processing loop
        if (end_program) exit(0);
    }
 }