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#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <setjmp.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
static jmp_buf b;
static void
__attribute__ ((noinline))
f (void)
{
char buf[1000];
asm volatile ("" : "=m" (buf));
if (setjmp (b) != 0)
{
puts ("second longjmp succeeded");
exit (1);
}
}
static bool expected_to_fail;
static void
handler (int sig)
{
if (expected_to_fail)
_exit (0);
else
{
static const char msg[] = "unexpected longjmp failure\n";
TEMP_FAILURE_RETRY (write (STDOUT_FILENO, msg, sizeof (msg) - 1));
_exit (1);
}
}
int
main (void)
{
struct sigaction sa;
sa.sa_handler = handler;
sa.sa_flags = 0;
sigemptyset (&sa.sa_mask);
sigaction (SIGABRT, &sa, NULL);
/* Avoid all the buffer overflow messages on stderr. */
int fd = open (_PATH_DEVNULL, O_WRONLY);
if (fd == -1)
close (STDERR_FILENO);
else
{
dup2 (fd, STDERR_FILENO);
close (fd);
}
setenv ("LIBC_FATAL_STDERR_", "1", 1);
expected_to_fail = false;
if (setjmp (b) == 0)
{
longjmp (b, 1);
/* NOTREACHED */
printf ("first longjmp returned\n");
return 1;
}
expected_to_fail = true;
f ();
longjmp (b, 1);
puts ("second longjmp returned");
return 1;
}
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