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 <[email protected]>
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
20 static int fds_limit, first, i;
21 static int *fds;
22 static char fname[20];
23
setup(void)24 static 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
run(void)47 static 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
cleanup(void)53 static 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
65 static struct tst_test test = {
66 .test_all = run,
67 .setup = setup,
68 .cleanup = cleanup,
69 .needs_tmpdir = 1
70 };
71