1 /* $NetBSD: t_empty.c,v 1.2 2024/08/23 07:13:50 rin Exp $ */
2
3 /*-
4 * Copyright (c) 2021 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __RCSID("$NetBSD: t_empty.c,v 1.2 2024/08/23 07:13:50 rin Exp $");
31
32 #include <sys/event.h>
33 #include <sys/socket.h>
34 #include <sys/time.h>
35 #include <sys/types.h>
36
37 #include <netinet/in.h>
38
39 #include <err.h>
40 #include <errno.h>
41 #include <fcntl.h>
42 #include <stdbool.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <unistd.h>
46
47 #include <atf-c.h>
48
49 static void
test_empty(int readfd,int writefd,bool is_tcp)50 test_empty(int readfd, int writefd, bool is_tcp)
51 {
52 struct timespec ts = { 0, 0 };
53 struct kevent event;
54 int kq, error, sndbufsize;
55 char buf[1024] = { 0 };
56 ssize_t rv;
57
58 ATF_REQUIRE((kq = kqueue()) >= 0);
59
60 EV_SET(&event, writefd, EVFILT_EMPTY, EV_ADD, 0, 0, NULL);
61 ATF_REQUIRE(kevent(kq, &event, 1, NULL, 0, NULL) == 0);
62
63 /* Check that EMPTY is true. */
64 memset(&event, 0, sizeof(event));
65 ATF_REQUIRE(kevent(kq, NULL, 0, &event, 1, &ts) == 1);
66 ATF_REQUIRE(event.ident == (uintptr_t)writefd);
67 ATF_REQUIRE(event.filter == EVFILT_EMPTY);
68
69 if (is_tcp) {
70 /*
71 * Get the write socket buffer size so that we can set
72 * the read socket buffer size to something larger
73 * later on.
74 */
75 socklen_t slen = sizeof(sndbufsize);
76 ATF_REQUIRE(getsockopt(writefd, SOL_SOCKET,
77 SO_SNDBUF, &sndbufsize, &slen) == 0);
78
79 /*
80 * Set the receive buffer size to 1, slamming shut
81 * the TCP receive window, thus trapping all of the
82 * data in the sender's queue.
83 */
84 int val = 1;
85 ATF_REQUIRE(setsockopt(readfd, SOL_SOCKET,
86 SO_RCVBUF, &val, sizeof(val)) == 0);
87 }
88
89 /* Write until the write buffer is full. */
90 for (rv = 0; rv != -1;) {
91 rv = write(writefd, buf, sizeof(buf));
92 error = errno;
93 ATF_REQUIRE(rv > 0 || (rv == -1 && error == EAGAIN));
94 }
95
96 /* Check that EMPTY is false. */
97 ATF_REQUIRE(kevent(kq, NULL, 0, &event, 1, &ts) == 0);
98
99 if (is_tcp) {
100 /*
101 * Set the receive buffer size to something larger than
102 * the sender's send buffer.
103 */
104 int val = sndbufsize + 128;
105 ATF_REQUIRE(setsockopt(readfd, SOL_SOCKET,
106 SO_RCVBUF, &val, sizeof(val)) == 0);
107 }
108
109 /* Read all of the data that's available. */
110 for (rv = 0; rv != -1;) {
111 rv = read(readfd, buf, sizeof(buf));
112 error = errno;
113 ATF_REQUIRE(rv > 0 || (rv == -1 && error == EAGAIN));
114 }
115
116 /*
117 * Check that EMPTY is true. Check a few times (TCP might
118 * not drain immediately).
119 */
120 if (is_tcp) {
121 for (rv = 0; rv < 5; rv++) {
122 if (kevent(kq, NULL, 0, &event, 1, &ts) == 1) {
123 break;
124 }
125 }
126 sleep(1);
127 }
128 memset(&event, 0, sizeof(event));
129 ATF_REQUIRE(kevent(kq, NULL, 0, &event, 1, &ts) == 1);
130 ATF_REQUIRE(event.ident == (uintptr_t)writefd);
131 ATF_REQUIRE(event.filter == EVFILT_EMPTY);
132 }
133
134 ATF_TC(sock_tcp);
ATF_TC_HEAD(sock_tcp,tc)135 ATF_TC_HEAD(sock_tcp, tc)
136 {
137 atf_tc_set_md_var(tc, "descr",
138 "Test EVFILT_EMPTY with TCP sockets.");
139 }
140
ATF_TC_BODY(sock_tcp,tc)141 ATF_TC_BODY(sock_tcp, tc)
142 {
143 int readsock, writesock;
144 socklen_t slen;
145
146 ATF_REQUIRE((readsock =
147 socket(PF_INET, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP)) != -1);
148 ATF_REQUIRE((writesock =
149 socket(PF_INET, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP)) != -1);
150
151 struct sockaddr_in sin = {
152 .sin_len = sizeof(sin),
153 .sin_family = AF_INET,
154 .sin_port = 0, /* no need to swap 0 */
155 .sin_addr = { .s_addr = htonl(INADDR_LOOPBACK) },
156 };
157 ATF_REQUIRE(bind(readsock, (struct sockaddr *)&sin,
158 sizeof(sin)) == 0);
159 ATF_REQUIRE(listen(readsock, 1) == 0);
160 slen = sizeof(sin);
161 ATF_REQUIRE(getsockname(readsock, (struct sockaddr *)&sin, &slen) == 0);
162
163 ATF_REQUIRE_ERRNO(EINPROGRESS,
164 connect(writesock, (struct sockaddr *)&sin, sizeof(sin)) == -1);
165
166 /* XXX Avoid race between connect(2) and accept(2). */
167 sleep(1);
168
169 slen = sizeof(sin);
170 ATF_REQUIRE((readsock = accept(readsock, (struct sockaddr *)&sin,
171 &slen)) != -1);
172
173 test_empty(readsock, writesock, true);
174 }
175
ATF_TP_ADD_TCS(tp)176 ATF_TP_ADD_TCS(tp)
177 {
178 ATF_TP_ADD_TC(tp, sock_tcp);
179
180 return atf_no_error();
181 }
182