xref: /freebsd/sys/contrib/openzfs/tests/zfs-tests/tests/functional/libzfs/many_fds.c (revision 61145dc2b94f12f6a47344fb9aac702321880e43)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * CDDL HEADER START
4  *
5  * The contents of this file are subject to the terms of the
6  * Common Development and Distribution License (the "License").
7  * You may not use this file except in compliance with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright (C) 2015 STRATO AG.
25  */
26 #include <err.h>
27 #include <fcntl.h>
28 #include <libzfs.h>
29 #include <sys/resource.h>
30 #include <sys/stat.h>
31 #include <sys/types.h>
32 #include <unistd.h>
33 
34 /*
35  * Check if libzfs works with more than 255 held file handles.
36  */
37 int
main(void)38 main(void)
39 {
40 	struct rlimit limit = {
41 		.rlim_cur = 64 * 1024,
42 		.rlim_max = 64 * 1024,
43 	};
44 	if (setrlimit(RLIMIT_NOFILE, &limit) != 0)
45 		err(1, "setrlimit()");
46 
47 	int fd = open("/dev/null", O_RDONLY);
48 	if (fd == -1)
49 			err(1, "open()");
50 	for (int i = 0; i < limit.rlim_cur / 2; ++i)
51 		if (dup(fd) == -1)
52 			err(1, "dup()");
53 
54 	libzfs_handle_t *h = libzfs_init();
55 	if (h == NULL)
56 		err(1, "libzfs_init()");
57 
58 	libzfs_fini(h);
59 }
60