musl/src/exit/exit.c

#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include "libc.h"
#include "atomic.h"
#include "syscall.h"

static void dummy()
{
}

/* __toread.c, __towrite.c, and atexit.c override these */
weak_alias(dummy, __funcs_on_exit);
weak_alias(dummy, __flush_on_exit);
weak_alias(dummy, __seek_on_exit);

_Noreturn void exit(int code)
{
	static int lock;

	/* If more than one thread calls exit, hang until _Exit ends it all */
	while (a_swap(&lock, 1)) __syscall(SYS_pause);

	__funcs_on_exit();
	if (libc.fini) libc.fini();
	if (libc.ldso_fini) libc.ldso_fini();
	__flush_on_exit();
	__seek_on_exit();

	_Exit(code);
	for(;;);
}