1 #include <sys/types.h>
2 #include <sys/socket.h>
3 #include <sys/time.h>
4 #include <sys/un.h>
5
6 #include <err.h>
7 #include <errno.h>
8 #include <signal.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <unistd.h>
13
14 #define READ_BLOCK_TIME 5 /* unit: sec */
15
16 static void
sig_alarm(int sig __unused)17 sig_alarm(int sig __unused)
18 {
19 #define PANIC_STRING "read blocks\n"
20
21 write(2, PANIC_STRING, strlen(PANIC_STRING));
22 abort();
23 }
24
25 int
main(void)26 main(void)
27 {
28 struct itimerval it;
29 int s[2], n, error;
30 char buf;
31
32 if (socketpair(AF_UNIX, SOCK_DGRAM | SOCK_NONBLOCK, 0, s) < 0)
33 err(1, "socketpair failed");
34
35 memset(&it, 0, sizeof(it));
36 it.it_value.tv_sec = READ_BLOCK_TIME;
37 if (signal(SIGALRM, sig_alarm) == SIG_ERR)
38 err(1, "signal failed");
39 if (setitimer(ITIMER_REAL, &it, NULL) < 0)
40 err(1, "setitimer failed");
41
42 n = read(s[0], &buf, 1);
43 if (n < 0) {
44 error = errno;
45 if (error != EAGAIN) {
46 warnx("invalid errno %d", error);
47 abort();
48 }
49 } else {
50 warnx("read0 works");
51 abort();
52 }
53
54 n = read(s[1], &buf, 1);
55 if (n < 0) {
56 error = errno;
57 if (error != EAGAIN) {
58 warnx("invalid errno %d", error);
59 abort();
60 }
61 } else {
62 warnx("read1 works");
63 abort();
64 }
65
66 fprintf(stderr, "passed\n");
67 exit(0);
68 }
69