1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
14 */
15
16 #include <err.h>
17 #include <errno.h>
18 #include <limits.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <sys/debug.h>
22 #include <sys/eventfd.h>
23 #include <unistd.h>
24
25 static int
readn(int fd,uint_t n)26 readn(int fd, uint_t n)
27 {
28 uint_t i;
29 int failures = 0;
30
31 for (i = 0; i < n; i++) {
32 eventfd_t v = 0xdeadbeef;
33 int ret;
34
35 ret = eventfd_read(fd, &v);
36 if (ret != 0) {
37 warn("Reading %u/%u got ret %d (expected 0)",
38 i + 1, n, ret);
39 failures++;
40 } else if (v != 1) {
41 warnx("Reading %u/%u got value %"PRIu64" (expected 1)",
42 i + 1, n, v);
43 failures++;
44 }
45 }
46
47 return (failures);
48 }
49
50 static int
check_nosem(int fd)51 check_nosem(int fd)
52 {
53 eventfd_t v = 0xdeadbeef;
54 int failures = 0;
55 int ret;
56
57 ret = eventfd_read(fd, &v);
58
59 if (ret != -1) {
60 warnx("no semaphores read got ret %d (expected -1)", ret);
61 failures++;
62 }
63
64 if (errno != EAGAIN) {
65 warn("no semaphores read expected EAGAIN but got");
66 failures++;
67 }
68
69 if (v != 0xdeadbeef) {
70 warnx("no semaphores read modified value to %"PRIx64, v);
71 failures++;
72 }
73
74 return (failures);
75 }
76
77 static int
check_badwrite(int fd)78 check_badwrite(int fd)
79 {
80 int failures = 0;
81 int ret;
82
83 ret = eventfd_write(fd, ULLONG_MAX);
84
85 if (ret != -1) {
86 warnx("bad write got ret %d (expected -1)", ret);
87 failures++;
88 }
89
90 if (errno != EINVAL) {
91 warn("bad write expected EINVAL but got");
92 failures++;
93 }
94
95 return (failures);
96 }
97
98 int
main(void)99 main(void)
100 {
101 int fd, failures = 0;
102
103 /* Test eventfd semaphore semantics */
104 fd = eventfd(2, EFD_NONBLOCK | EFD_CLOEXEC | EFD_SEMAPHORE);
105 if (fd == -1)
106 err(EXIT_FAILURE, "Could not create eventfd semaphore");
107
108 /* Consume the available semaphores */
109 failures += readn(fd, 2);
110
111 /* The next read should return -1/EAGAIN */
112 failures += check_nosem(fd);
113
114 /* Return two + three semaphores */
115 if (eventfd_write(fd, 2) != 0) {
116 warn("Error while returning two semaphores");
117 failures++;
118 }
119 if (eventfd_write(fd, 3) != 0) {
120 warn("Error while returning three semaphores");
121 failures++;
122 }
123
124 /* Consume the available semaphores */
125 failures += readn(fd, 5);
126
127 /* The next read should return -1/EAGAIN */
128 failures += check_nosem(fd);
129
130 /*
131 * Check that a writing too large a value results in an error from
132 * eventfd_write() - testing that an error from the underlying write()
133 * is passed back.
134 */
135 failures += check_badwrite(fd);
136
137 VERIFY0(close(fd));
138
139 return (failures == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
140 }
141