source: azure_iot_hub/trunk/musl-1.1.18/src/exit/at_quick_exit.c@ 389

#include <stdlib.h>
#include "libc.h"

#define COUNT 32

static void (*funcs[COUNT])(void);
static int count;
static volatile int lock[2];

void __funcs_on_quick_exit()
{
        void (*func)(void);
        LOCK(lock);
        while (count > 0) {
                func = funcs[--count];
                UNLOCK(lock);
                func();
                LOCK(lock);
        }
}

int at_quick_exit(void (*func)(void))
{
        if (count == 32) return -1;
        LOCK(lock);
        funcs[count++] = func;
        UNLOCK(lock);
        return 0;
}