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/* Helper file for tst-{atexit,at_quick_exit,cxa_atexit,on_exit}.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#define MAX_ATEXIT 20 /* Large enough for current set of invocations. */
static char crumbs[MAX_ATEXIT];
static int next_slot = 0;
/* Helper: flush stdout and _exit. */
static void
_exit_with_flush (int code)
{
fflush (stdout);
_exit (code);
}
static void
fn0 (void)
{
crumbs[next_slot++] = '0';
}
static void
fn1 (void)
{
crumbs[next_slot++] = '1';
}
static void
fn2 (void)
{
crumbs[next_slot++] = '2';
ATEXIT (fn1);
}
static void
fn3 (void)
{
crumbs[next_slot++] = '3';
ATEXIT (fn2);
ATEXIT (fn0);
}
static void
fn_final (void)
{
/* Arbitrary sequence matching current registrations. */
const char expected[] = "3021121130211";
if (strcmp (crumbs, expected) == 0)
_exit_with_flush (0);
printf ("crumbs: %s\n", crumbs);
printf ("expected: %s\n", expected);
_exit_with_flush (1);
}
/* This is currently just a basic test to verify that exit handlers execute
in LIFO order, even when the handlers register additional new handlers.
TODO: Additional tests that we should do:
1. POSIX says we need to support at least ATEXIT_MAX
2. ... */
static int
do_test (void)
{
/* Register this first so it can verify expected order of the rest. */
ATEXIT (fn_final);
ATEXIT (fn1);
ATEXIT (fn3);
ATEXIT (fn1);
ATEXIT (fn2);
ATEXIT (fn1);
ATEXIT (fn3);
/* Verify that handlers registered above are inherited across fork. */
const pid_t child = fork ();
switch (child)
{
case -1:
printf ("fork: %m\n");
_exit_with_flush (3);
case 0: /* Child. */
break;
default:
{
int status;
const pid_t exited = waitpid (child, &status, 0);
if (child != exited)
{
printf ("unexpected child: %d, expected %d\n", exited, child);
_exit_with_flush (4);
}
if (status != 0)
{
if (WIFEXITED (status))
printf ("unexpected exit status %d from child %d\n",
WEXITSTATUS (status), child);
else if (WIFSIGNALED (status))
printf ("unexpected signal %d from child %d\n",
WTERMSIG (status), child);
else
printf ("unexpected status %d from child %d\n", status, child);
_exit_with_flush (5);
}
}
break;
}
EXIT (2); /* If we see this exit code, fn_final must have not worked. */
}
#define TEST_FUNCTION do_test
#include <support/test-driver.c>
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