1 /* Test of select() substitute.
2 Copyright (C) 2008-2021 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17 /* Written by Paolo Bonzini, 2008. */
21 #include <sys/socket.h>
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
28 #include <sys/ioctl.h>
33 #if defined _WIN32 && ! defined __CYGWIN__
34 # define WINDOWS_NATIVE
37 #ifdef HAVE_SYS_WAIT_H
38 # include <sys/wait.h>
41 #define TEST_PORT 12345
44 typedef int (*select_fn) (int, fd_set *, fd_set *, fd_set *, struct timeval *);
47 /* Minimal testing infrastructure. */
52 failed (const char *reason)
56 printf ("failed (%s)\n", reason);
60 test (void (*fn) (select_fn), select_fn my_select, const char *msg)
63 printf ("%s... ", msg);
74 /* Funny socket code. */
77 open_server_socket (void)
80 struct sockaddr_in ia;
82 s = socket (AF_INET, SOCK_STREAM, 0);
85 setsockopt (s, SOL_SOCKET, SO_REUSEPORT, &x, sizeof (x));
87 memset (&ia, 0, sizeof (ia));
88 ia.sin_family = AF_INET;
89 inet_pton (AF_INET, "127.0.0.1", &ia.sin_addr);
90 ia.sin_port = htons (TEST_PORT);
91 if (bind (s, (struct sockaddr *) &ia, sizeof (ia)) < 0)
97 if (listen (s, 1) < 0)
107 connect_to_socket (bool blocking)
110 struct sockaddr_in ia;
112 s = socket (AF_INET, SOCK_STREAM, 0);
114 memset (&ia, 0, sizeof (ia));
115 ia.sin_family = AF_INET;
116 inet_pton (AF_INET, "127.0.0.1", &ia.sin_addr);
117 ia.sin_port = htons (TEST_PORT);
121 #ifdef WINDOWS_NATIVE
122 unsigned long iMode = 1;
123 ioctl (s, FIONBIO, (char *) &iMode);
125 #elif defined F_GETFL
126 int oldflags = fcntl (s, F_GETFL, NULL);
128 if (!(oldflags & O_NONBLOCK))
129 fcntl (s, F_SETFL, oldflags | O_NONBLOCK);
133 if (connect (s, (struct sockaddr *) &ia, sizeof (ia)) < 0
134 && (blocking || errno != EINPROGRESS))
144 /* A slightly more convenient interface to select(2).
145 Waits until a specific event occurs on a file descriptor FD.
146 EV is a bit mask of events to look for:
147 SEL_IN - input can be polled without blocking,
148 SEL_OUT - output can be provided without blocking,
149 SEL_EXC - an exception occurred,
150 A maximum wait time is specified by TIMEOUT.
151 *TIMEOUT = { 0, 0 } means to return immediately,
152 TIMEOUT = NULL means to wait indefinitely. */
154 enum { SEL_IN = 1, SEL_OUT = 2, SEL_EXC = 4 };
157 do_select (int fd, int ev, struct timeval *timeout, select_fn my_select)
159 fd_set rfds, wfds, xfds;
171 r = my_select (fd + 1, &rfds, &wfds, &xfds, timeout);
176 if (FD_ISSET (fd, &rfds))
178 if (FD_ISSET (fd, &wfds))
180 if (FD_ISSET (fd, &xfds))
183 failed ("select returned 0");
185 failed ("select returned unrequested events");
191 do_select_nowait (int fd, int ev, select_fn my_select)
196 return do_select (fd, ev, &tv0, my_select);
200 do_select_wait (int fd, int ev, select_fn my_select)
202 return do_select (fd, ev, NULL, my_select);
206 /* Test select(2) for TTYs. */
210 test_tty (select_fn my_select)
212 if (do_select_nowait (0, SEL_IN, my_select) != 0)
214 if (do_select_nowait (0, SEL_OUT, my_select) == 0)
215 failed ("cannot write");
217 if (do_select_wait (0, SEL_IN, my_select) == 0)
218 failed ("return with infinite timeout");
221 if (do_select_nowait (0, SEL_IN, my_select) != 0)
222 failed ("can read after getc");
228 do_select_bad_nfd_nowait (int nfd, select_fn my_select)
234 return my_select (nfd, NULL, NULL, NULL, &tv0);
238 test_bad_nfd (select_fn my_select)
240 if (do_select_bad_nfd_nowait (-1, my_select) != -1 || errno != EINVAL)
241 failed ("invalid errno after negative nfds");
242 /* Can't test FD_SETSIZE + 1 for EINVAL, since some systems allow
243 dynamically larger set size by redefining FD_SETSIZE anywhere up
244 to the actual maximum fd. */
246 if (do_select_bad_nfd_nowait (FD_SETSIZE + 1, my_select) != -1
248 failed ("invalid errno after bogus nfds");
252 /* Test select(2) on invalid file descriptors. */
255 do_select_bad_fd (int fd, int ev, struct timeval *timeout, select_fn my_select)
257 fd_set rfds, wfds, xfds;
269 return my_select (fd + 1, &rfds, &wfds, &xfds, timeout);
270 /* In this case, when fd is invalid, on some platforms, the bit for fd
271 is left alone in the fd_set, whereas on other platforms it is cleared.
272 So, don't check the bit for fd here. */
276 do_select_bad_fd_nowait (int fd, int ev, select_fn my_select)
281 return do_select_bad_fd (fd, ev, &tv0, my_select);
285 test_bad_fd (select_fn my_select)
287 /* This tests fails on OSF/1 and native Windows, even with fd = 16. */
288 #if !(defined __osf__ || defined WINDOWS_NATIVE)
291 /* On Linux, Mac OS X, *BSD, values of fd like 99 or 399 are discarded
292 by the kernel early and therefore do *not* lead to EBADF, as required
294 # if defined __linux__ || (defined __APPLE__ && defined __MACH__) || (defined __FreeBSD__ || defined __DragonFly__) || defined __OpenBSD__ || defined __NetBSD__
299 /* Even on the best POSIX compliant platforms, values of fd >= FD_SETSIZE
300 require an nfds argument that is > FD_SETSIZE and thus may lead to EINVAL,
302 if (fd >= FD_SETSIZE)
306 if (do_select_bad_fd_nowait (fd, SEL_IN, my_select) == 0 || errno != EBADF)
307 failed ("invalid fd among rfds");
308 if (do_select_bad_fd_nowait (fd, SEL_OUT, my_select) == 0 || errno != EBADF)
309 failed ("invalid fd among wfds");
310 if (do_select_bad_fd_nowait (fd, SEL_EXC, my_select) == 0 || errno != EBADF)
311 failed ("invalid fd among xfds");
316 /* Test select(2) for unconnected nonblocking sockets. */
319 test_connect_first (select_fn my_select)
321 int s = open_server_socket ();
322 struct sockaddr_in ia;
327 if (do_select_nowait (s, SEL_IN | SEL_EXC, my_select) != 0)
328 failed ("can read, socket not connected");
330 c1 = connect_to_socket (false);
332 if (do_select_wait (s, SEL_IN | SEL_EXC, my_select) != SEL_IN)
333 failed ("expecting readability on passive socket");
334 if (do_select_nowait (s, SEL_IN | SEL_EXC, my_select) != SEL_IN)
335 failed ("expecting readability on passive socket");
337 addrlen = sizeof (ia);
338 c2 = accept (s, (struct sockaddr *) &ia, &addrlen);
339 ASSERT (close (s) == 0);
340 ASSERT (close (c1) == 0);
341 ASSERT (close (c2) == 0);
345 /* Test select(2) for unconnected blocking sockets. */
348 test_accept_first (select_fn my_select)
350 #ifndef WINDOWS_NATIVE
351 int s = open_server_socket ();
352 struct sockaddr_in ia;
363 addrlen = sizeof (ia);
364 c = accept (s, (struct sockaddr *) &ia, &addrlen);
365 ASSERT (close (s) == 0);
366 ASSERT (write (c, "foo", 3) == 3);
367 ASSERT (read (c, buf, 3) == 3);
368 shutdown (c, SHUT_RD);
369 ASSERT (close (c) == 0);
374 ASSERT (close (s) == 0);
375 c = connect_to_socket (true);
376 if (do_select_nowait (c, SEL_OUT, my_select) != SEL_OUT)
377 failed ("cannot write after blocking connect");
378 ASSERT (write (c, "foo", 3) == 3);
380 if (do_select_wait (c, SEL_IN, my_select) != SEL_IN)
381 failed ("cannot read data left in the socket by closed process");
382 ASSERT (read (c, buf, 3) == 3);
383 ASSERT (write (c, "foo", 3) == 3);
384 (void) close (c); /* may fail with errno = ECONNRESET */
390 /* Common code for pipes and connected sockets. */
393 test_pair (int rd, int wd, select_fn my_select)
396 if (do_select_wait (wd, SEL_IN | SEL_OUT | SEL_EXC, my_select) != SEL_OUT)
397 failed ("expecting writability before writing");
398 if (do_select_nowait (wd, SEL_IN | SEL_OUT | SEL_EXC, my_select) != SEL_OUT)
399 failed ("expecting writability before writing");
401 ASSERT (write (wd, "foo", 3) == 3);
402 if (do_select_wait (rd, SEL_IN, my_select) != SEL_IN)
403 failed ("expecting readability after writing");
404 if (do_select_nowait (rd, SEL_IN, my_select) != SEL_IN)
405 failed ("expecting readability after writing");
407 ASSERT (read (rd, buf, 3) == 3);
411 /* Test select(2) on connected sockets. */
414 test_socket_pair (select_fn my_select)
416 struct sockaddr_in ia;
418 socklen_t addrlen = sizeof (ia);
419 int s = open_server_socket ();
420 int c1 = connect_to_socket (false);
421 int c2 = accept (s, (struct sockaddr *) &ia, &addrlen);
423 ASSERT (close (s) == 0);
425 test_pair (c1, c2, my_select);
426 ASSERT (close (c1) == 0);
427 ASSERT (write (c2, "foo", 3) == 3);
428 (void) close (c2); /* may fail with errno = ECONNRESET */
432 /* Test select(2) on pipes. */
435 test_pipe (select_fn my_select)
439 ASSERT (pipe (fd) == 0);
440 test_pair (fd[0], fd[1], my_select);
441 ASSERT (close (fd[0]) == 0);
442 ASSERT (close (fd[1]) == 0);
449 test_function (select_fn my_select)
454 printf ("Please press Enter\n");
455 test (test_tty, "TTY", my_select);
458 result += test (test_bad_nfd, my_select, "Invalid nfd test");
459 result += test (test_bad_fd, my_select, "Invalid fd test");
460 result += test (test_connect_first, my_select, "Unconnected socket test");
461 result += test (test_socket_pair, my_select, "Connected sockets test");
462 result += test (test_accept_first, my_select, "General socket test with fork");
463 result += test (test_pipe, my_select, "Pipe test");