1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) International Business Machines  Corp., 2001
4 * Copyright (c) 2022 SUSE LLC Avinesh Kumar <avinesh.kumar@suse.com>
5 */
6
7/*\
8 * [Description]
9 *
10 * Verify that open(2) fails with EMFILE when per-process limit on the number
11 * of open file descriptors has been reached.
12 */
13
14#include <stdio.h>
15#include <stdlib.h>
16#include "tst_test.h"
17
18#define FNAME "open04"
19
20static int fds_limit, first, i;
21static int *fds;
22static char fname[20];
23
24static void setup(void)
25{
26	int fd;
27
28	fds_limit = getdtablesize();
29	first = SAFE_OPEN(FNAME, O_RDWR | O_CREAT, 0777);
30
31	fds = SAFE_MALLOC(sizeof(int) * (fds_limit - first));
32	fds[0] = first;
33
34	for (i = first + 1; i < fds_limit; i++) {
35		sprintf(fname, FNAME ".%d", i);
36		fd = open(fname, O_RDWR | O_CREAT, 0777);
37		if (fd == -1) {
38			if (errno != EMFILE)
39				tst_brk(TBROK, "Expected EMFILE but got %d", errno);
40			fds_limit = i;
41			break;
42		}
43		fds[i - first] = fd;
44	}
45}
46
47static void run(void)
48{
49	sprintf(fname, FNAME ".%d", fds_limit);
50	TST_EXP_FAIL2(open(fname, O_RDWR | O_CREAT, 0777), EMFILE);
51}
52
53static void cleanup(void)
54{
55	if (!first || !fds)
56		return;
57
58	for (i = first; i < fds_limit; i++)
59		SAFE_CLOSE(fds[i - first]);
60
61	if (fds)
62		free(fds);
63}
64
65static struct tst_test test = {
66	.test_all = run,
67	.setup = setup,
68	.cleanup = cleanup,
69	.needs_tmpdir = 1
70};
71