1 2 #include <sys/types.h> 3 #include <sys/event.h> 4 #include <sys/select.h> 5 #include <sys/wait.h> 6 #include <err.h> 7 #include <fcntl.h> 8 #include <mqueue.h> 9 #include <signal.h> 10 #include <stdio.h> 11 #include <stdlib.h> 12 #include <unistd.h> 13 14 #define MQNAME "/mytstqueue4" 15 #define LOOPS 1000 16 #define PRIO 10 17 18 static void 19 sighandler(int sig __unused) 20 { 21 write(1, "timeout\n", 8); 22 _exit(1); 23 } 24 25 int 26 main(void) 27 { 28 struct kevent kev; 29 struct mq_attr attr; 30 mqd_t mq; 31 int kq, status; 32 pid_t pid; 33 34 mq_unlink(MQNAME); 35 36 attr.mq_maxmsg = 5; 37 attr.mq_msgsize = 128; 38 mq = mq_open(MQNAME, O_CREAT | O_RDWR | O_EXCL, 0666, &attr); 39 if (mq == (mqd_t) -1) 40 err(1, "mq_open()"); 41 status = mq_getattr(mq, &attr); 42 if (status) 43 err(1, "mq_getattr()"); 44 pid = fork(); 45 if (pid == 0) { /* child */ 46 char *buf; 47 int j, i; 48 unsigned int prio; 49 50 mq_close(mq); 51 kq = kqueue(); 52 mq = mq_open(MQNAME, O_RDWR); 53 if (mq == (mqd_t)-1) 54 err(1, "child: mq_open"); 55 EV_SET(&kev, mq_getfd_np(mq), EVFILT_READ, EV_ADD, 0, 0, 0); 56 status = kevent(kq, &kev, 1, NULL, 0, NULL); 57 if (status == -1) 58 err(1, "child: kevent"); 59 buf = malloc(attr.mq_msgsize); 60 for (j = 0; j < LOOPS; ++j) { 61 alarm(3); 62 status = kevent(kq, NULL, 0, &kev, 1, NULL); 63 if (status != 1) 64 err(1, "child: kevent 2"); 65 status = mq_receive(mq, buf, attr.mq_msgsize, &prio); 66 if (status == -1) 67 err(2, "child: mq_receive"); 68 for (i = 0; i < attr.mq_msgsize; ++i) 69 if (buf[i] != i) 70 err(3, "child: message data corrupted"); 71 if (prio != PRIO) 72 err(4, "child: priority is incorrect: %d", 73 prio); 74 } 75 alarm(0); 76 free(buf); 77 mq_close(mq); 78 return (0); 79 } else if (pid == -1) { 80 err(1, "fork()"); 81 } else { 82 char *buf; 83 int i, j; 84 85 signal(SIGALRM, sighandler); 86 kq = kqueue(); 87 EV_SET(&kev, mq_getfd_np(mq), EVFILT_WRITE, EV_ADD, 0, 0, 0); 88 status = kevent(kq, &kev, 1, NULL, 0, NULL); 89 if (status == -1) 90 err(1, "kevent"); 91 buf = malloc(attr.mq_msgsize); 92 for (j = 0; j < LOOPS; ++j) { 93 for (i = 0; i < attr.mq_msgsize; ++i) { 94 buf[i] = i; 95 } 96 alarm(3); 97 status = kevent(kq, NULL, 0, &kev, 1, NULL); 98 if (status != 1) 99 err(1, "child: kevent 2"); 100 status = mq_send(mq, buf, attr.mq_msgsize, PRIO); 101 if (status) { 102 err(2, "mq_send()"); 103 } 104 } 105 free(buf); 106 alarm(3); 107 wait(&status); 108 alarm(0); 109 } 110 status = mq_close(mq); 111 if (status) 112 err(1, "mq_close"); 113 mq_unlink(MQNAME); 114 return (0); 115 } 116