1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2020 Jan Kokem��ller
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/event.h>
33#include <sys/stat.h>
34
35#include <errno.h>
36#include <fcntl.h>
37#include <limits.h>
38#include <poll.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <time.h>
42#include <unistd.h>
43
44#include <atf-c.h>
45
46ATF_TC_WITHOUT_HEAD(fifo_kqueue__writes);
47ATF_TC_BODY(fifo_kqueue__writes, tc)
48{
49	int p[2] = { -1, -1 };
50
51	ATF_REQUIRE(mkfifo("testfifo", 0600) == 0);
52
53	ATF_REQUIRE((p[0] = open("testfifo",
54	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
55	ATF_REQUIRE((p[1] = open("testfifo",
56	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
57
58	int kq = kqueue();
59	ATF_REQUIRE(kq >= 0);
60
61	struct kevent kev[32];
62	EV_SET(&kev[0], p[1], EVFILT_WRITE, EV_ADD | EV_CLEAR, 0, 0, 0);
63	EV_SET(&kev[1], p[1], EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0);
64
65	ATF_REQUIRE(kevent(kq, kev, 2, NULL, 0, NULL) == 0);
66
67	/* A new writer should immediately get a EVFILT_WRITE event. */
68
69	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
70	    &(struct timespec) { 0, 0 }) == 1);
71	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
72	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
73	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
74	ATF_REQUIRE(kev[0].fflags == 0);
75	ATF_REQUIRE(kev[0].data == 16384);
76	ATF_REQUIRE(kev[0].udata == 0);
77
78	/* Filling up the pipe should make the EVFILT_WRITE disappear. */
79
80	char c = 0;
81	ssize_t r;
82	while ((r = write(p[1], &c, 1)) == 1) {
83	}
84	ATF_REQUIRE(r < 0);
85	ATF_REQUIRE(errno == EAGAIN || errno == EWOULDBLOCK);
86
87	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
88	    &(struct timespec) { 0, 0 }) == 0);
89
90	/* Reading (PIPE_BUF - 1) bytes will not trigger a EVFILT_WRITE yet. */
91
92	for (int i = 0; i < PIPE_BUF - 1; ++i) {
93		ATF_REQUIRE(read(p[0], &c, 1) == 1);
94	}
95
96	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
97	    &(struct timespec) { 0, 0 }) == 0);
98
99	/* Reading one additional byte triggers the EVFILT_WRITE. */
100
101	ATF_REQUIRE(read(p[0], &c, 1) == 1);
102
103	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
104	    &(struct timespec) { 0, 0 }) == 1);
105	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
106	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
107	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
108	ATF_REQUIRE(kev[0].fflags == 0);
109	ATF_REQUIRE(kev[0].data == PIPE_BUF);
110	ATF_REQUIRE(kev[0].udata == 0);
111
112	/*
113	 * Reading another byte triggers the EVFILT_WRITE again with a changed
114	 * 'data' field.
115	 */
116
117	ATF_REQUIRE(read(p[0], &c, 1) == 1);
118
119	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
120	    &(struct timespec) { 0, 0 }) == 1);
121	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
122	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
123	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
124	ATF_REQUIRE(kev[0].fflags == 0);
125	ATF_REQUIRE(kev[0].data == PIPE_BUF + 1);
126	ATF_REQUIRE(kev[0].udata == 0);
127
128	/*
129	 * Closing the read end should make a EV_EOF appear but leave the 'data'
130	 * field unchanged.
131	 */
132
133	ATF_REQUIRE(close(p[0]) == 0);
134
135	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev), NULL) == 1);
136	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
137	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
138	ATF_REQUIRE(kev[0].flags == (EV_CLEAR | EV_EOF));
139	ATF_REQUIRE(kev[0].fflags == 0);
140	ATF_REQUIRE(kev[0].data == PIPE_BUF + 1);
141	ATF_REQUIRE(kev[0].udata == 0);
142
143	ATF_REQUIRE(close(kq) == 0);
144	ATF_REQUIRE(close(p[1]) == 0);
145}
146
147ATF_TC_WITHOUT_HEAD(fifo_kqueue__connecting_reader);
148ATF_TC_BODY(fifo_kqueue__connecting_reader, tc)
149{
150	int p[2] = { -1, -1 };
151
152	ATF_REQUIRE(mkfifo("testfifo", 0600) == 0);
153
154	ATF_REQUIRE((p[0] = open("testfifo",
155	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
156	ATF_REQUIRE((p[1] = open("testfifo",
157	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
158
159	int kq = kqueue();
160	ATF_REQUIRE(kq >= 0);
161
162	struct kevent kev[32];
163	EV_SET(&kev[0], p[1], EVFILT_WRITE, EV_ADD | EV_CLEAR, 0, 0, 0);
164	EV_SET(&kev[1], p[1], EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0);
165
166	ATF_REQUIRE(kevent(kq, kev, 2, NULL, 0, NULL) == 0);
167
168	/* A new writer should immediately get a EVFILT_WRITE event. */
169
170	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
171	    &(struct timespec) { 0, 0 }) == 1);
172	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
173	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
174	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
175	    &(struct timespec) { 0, 0 }) == 0);
176
177	/*
178	 * Filling the pipe, reading (PIPE_BUF + 1) bytes, then closing the
179	 * read end leads to a EVFILT_WRITE with EV_EOF set.
180	 */
181
182	char c = 0;
183	ssize_t r;
184	while ((r = write(p[1], &c, 1)) == 1) {
185	}
186	ATF_REQUIRE(r < 0);
187	ATF_REQUIRE(errno == EAGAIN || errno == EWOULDBLOCK);
188
189	for (int i = 0; i < PIPE_BUF + 1; ++i) {
190		ATF_REQUIRE(read(p[0], &c, 1) == 1);
191	}
192
193	ATF_REQUIRE(close(p[0]) == 0);
194
195	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev), NULL) == 1);
196	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
197	ATF_REQUIRE((kev[0].flags & EV_EOF) != 0);
198	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
199	    &(struct timespec) { 0, 0 }) == 0);
200
201	/* Opening the reader again must trigger the EVFILT_WRITE. */
202
203	ATF_REQUIRE((p[0] = open("testfifo",
204	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
205
206	r = kevent(kq, NULL, 0, kev, nitems(kev), &(struct timespec) { 1, 0 });
207	ATF_REQUIRE(r == 1);
208	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[1]);
209	ATF_REQUIRE(kev[0].filter == EVFILT_WRITE);
210	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
211	ATF_REQUIRE(kev[0].fflags == 0);
212	ATF_REQUIRE(kev[0].data == PIPE_BUF + 1);
213	ATF_REQUIRE(kev[0].udata == 0);
214	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
215	    &(struct timespec) { 0, 0 }) == 0);
216
217	ATF_REQUIRE(close(kq) == 0);
218	ATF_REQUIRE(close(p[0]) == 0);
219	ATF_REQUIRE(close(p[1]) == 0);
220}
221
222/* Check that EVFILT_READ behaves sensibly on a FIFO reader. */
223ATF_TC_WITHOUT_HEAD(fifo_kqueue__reads);
224ATF_TC_BODY(fifo_kqueue__reads, tc)
225{
226	struct kevent kev[32];
227	ssize_t bytes, i, n;
228	int kq, p[2];
229	char c;
230
231	ATF_REQUIRE(mkfifo("testfifo", 0600) == 0);
232
233	ATF_REQUIRE((p[0] = open("testfifo",
234	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
235	ATF_REQUIRE((p[1] = open("testfifo",
236	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
237
238	bytes = 0;
239	c = 0;
240	while ((n = write(p[1], &c, 1)) == 1)
241		bytes++;
242	ATF_REQUIRE(n < 0);
243	ATF_REQUIRE(errno == EAGAIN || errno == EWOULDBLOCK);
244	ATF_REQUIRE(bytes > 1);
245
246	for (i = 0; i < bytes / 2; i++)
247		ATF_REQUIRE(read(p[0], &c, 1) == 1);
248	bytes -= i;
249
250	kq = kqueue();
251	ATF_REQUIRE(kq >= 0);
252
253	EV_SET(&kev[0], p[0], EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0);
254
255	ATF_REQUIRE(kevent(kq, kev, 1, NULL, 0, NULL) == 0);
256
257	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
258	    &(struct timespec){ 0, 0 }) == 1);
259	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[0]);
260	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
261	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
262	ATF_REQUIRE(kev[0].fflags == 0);
263	ATF_REQUIRE(kev[0].data == bytes);
264	ATF_REQUIRE(kev[0].udata == 0);
265
266	while (bytes-- > 0)
267		ATF_REQUIRE(read(p[0], &c, 1) == 1);
268	n = read(p[0], &c, 1);
269	ATF_REQUIRE(n < 0);
270	ATF_REQUIRE(errno == EAGAIN || errno == EWOULDBLOCK);
271
272	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
273	    &(struct timespec) { 0, 0 }) == 0);
274
275	ATF_REQUIRE(close(kq) == 0);
276	ATF_REQUIRE(close(p[0]) == 0);
277	ATF_REQUIRE(close(p[1]) == 0);
278}
279
280ATF_TC_WITHOUT_HEAD(fifo_kqueue__read_eof_wakeups);
281ATF_TC_BODY(fifo_kqueue__read_eof_wakeups, tc)
282{
283	int p[2] = { -1, -1 };
284
285	ATF_REQUIRE(mkfifo("testfifo", 0600) == 0);
286
287	ATF_REQUIRE((p[0] = open("testfifo",
288	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
289	ATF_REQUIRE((p[1] = open("testfifo",
290	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
291
292	int kq = kqueue();
293	ATF_REQUIRE(kq >= 0);
294
295	struct kevent kev[32];
296
297	EV_SET(&kev[0], p[0], EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0);
298	ATF_REQUIRE(kevent(kq, kev, 1, NULL, 0, NULL) == 0);
299
300	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
301	    &(struct timespec) { 0, 0 }) == 0);
302
303	/*
304	 * Closing the writer must trigger a EVFILT_READ edge with EV_EOF set.
305	 */
306
307	ATF_REQUIRE(close(p[1]) == 0);
308
309	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
310	    &(struct timespec) { 0, 0 }) == 1);
311	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[0]);
312	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
313	ATF_REQUIRE(kev[0].flags == (EV_EOF | EV_CLEAR));
314	ATF_REQUIRE(kev[0].fflags == 0);
315	ATF_REQUIRE(kev[0].data == 0);
316	ATF_REQUIRE(kev[0].udata == 0);
317
318	/*
319	 * Trying to read from a closed pipe should not trigger EVFILT_READ
320	 * edges.
321	 */
322
323	char c;
324	ATF_REQUIRE(read(p[0], &c, 1) == 0);
325
326	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
327	    &(struct timespec) { 0, 0 }) == 0);
328
329	ATF_REQUIRE(close(kq) == 0);
330	ATF_REQUIRE(close(p[0]) == 0);
331}
332
333ATF_TC_WITHOUT_HEAD(fifo_kqueue__read_eof_state_when_reconnecting);
334ATF_TC_BODY(fifo_kqueue__read_eof_state_when_reconnecting, tc)
335{
336	int p[2] = { -1, -1 };
337
338	ATF_REQUIRE(mkfifo("testfifo", 0600) == 0);
339
340	ATF_REQUIRE((p[0] = open("testfifo",
341	    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
342	ATF_REQUIRE((p[1] = open("testfifo",
343	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
344
345	int kq = kqueue();
346	ATF_REQUIRE(kq >= 0);
347
348	struct kevent kev[32];
349
350	EV_SET(&kev[0], p[0], EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, 0);
351	ATF_REQUIRE(kevent(kq, kev, 1, NULL, 0, NULL) == 0);
352
353	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
354	    &(struct timespec) { 0, 0 }) == 0);
355
356	/*
357	 * Closing the writer must trigger a EVFILT_READ edge with EV_EOF set.
358	 */
359
360	ATF_REQUIRE(close(p[1]) == 0);
361
362	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
363	    &(struct timespec) { 0, 0 }) == 1);
364	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[0]);
365	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
366	ATF_REQUIRE(kev[0].flags == (EV_EOF | EV_CLEAR));
367	ATF_REQUIRE(kev[0].fflags == 0);
368	ATF_REQUIRE(kev[0].data == 0);
369	ATF_REQUIRE(kev[0].udata == 0);
370
371	/* A new reader shouldn't see the EOF flag. */
372
373	{
374		int new_reader;
375		ATF_REQUIRE((new_reader = open("testfifo",
376		    O_RDONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
377
378		int new_kq = kqueue();
379		ATF_REQUIRE(new_kq >= 0);
380
381		struct kevent new_kev[32];
382		EV_SET(&new_kev[0], new_reader, EVFILT_READ, EV_ADD | EV_CLEAR,
383		    0, 0, 0);
384		ATF_REQUIRE(kevent(new_kq, new_kev, 1, NULL, 0, NULL) == 0);
385
386		ATF_REQUIRE(kevent(new_kq, NULL, 0, new_kev, nitems(new_kev),
387		    &(struct timespec) { 0, 0 }) == 0);
388
389		ATF_REQUIRE(close(new_kq) == 0);
390		ATF_REQUIRE(close(new_reader) == 0);
391	}
392
393	/*
394	 * Simply reopening the writer does not trigger the EVFILT_READ again --
395	 * EV_EOF should be cleared, but there is no data yet so the filter
396	 * does not trigger.
397	 */
398
399	ATF_REQUIRE((p[1] = open("testfifo",
400	    O_WRONLY | O_CLOEXEC | O_NONBLOCK)) >= 0);
401
402	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
403	    &(struct timespec) { 0, 0 }) == 0);
404
405	/* Writing a byte should trigger a EVFILT_READ. */
406
407	char c = 0;
408	ATF_REQUIRE(write(p[1], &c, 1) == 1);
409
410	ATF_REQUIRE(kevent(kq, NULL, 0, kev, nitems(kev),
411	    &(struct timespec) { 0, 0 }) == 1);
412	ATF_REQUIRE(kev[0].ident == (uintptr_t)p[0]);
413	ATF_REQUIRE(kev[0].filter == EVFILT_READ);
414	ATF_REQUIRE(kev[0].flags == EV_CLEAR);
415	ATF_REQUIRE(kev[0].fflags == 0);
416	ATF_REQUIRE(kev[0].data == 1);
417	ATF_REQUIRE(kev[0].udata == 0);
418
419	ATF_REQUIRE(close(kq) == 0);
420	ATF_REQUIRE(close(p[0]) == 0);
421	ATF_REQUIRE(close(p[1]) == 0);
422}
423
424ATF_TP_ADD_TCS(tp)
425{
426	ATF_TP_ADD_TC(tp, fifo_kqueue__writes);
427	ATF_TP_ADD_TC(tp, fifo_kqueue__connecting_reader);
428	ATF_TP_ADD_TC(tp, fifo_kqueue__reads);
429	ATF_TP_ADD_TC(tp, fifo_kqueue__read_eof_wakeups);
430	ATF_TP_ADD_TC(tp, fifo_kqueue__read_eof_state_when_reconnecting);
431
432	return atf_no_error();
433}
434