1 /* Test mq_notify.
2    Copyright (C) 2004-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <mqueue.h>
22 #include <limits.h>
23 #include <signal.h>
24 #include <stdint.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <sys/mman.h>
29 #include <sys/time.h>
30 #include <sys/wait.h>
31 #include <time.h>
32 #include <unistd.h>
33 #include <support/check.h>
34 #include "tst-mqueue.h"
35 
36 #if _POSIX_THREADS && defined SIGRTMIN && defined SA_SIGINFO
37 # include <pthread.h>
38 
39 volatile int rtmin_cnt;
40 volatile pid_t rtmin_pid;
41 volatile uid_t rtmin_uid;
42 volatile int rtmin_code;
43 volatile union sigval rtmin_sigval;
44 
45 static void
rtmin_handler(int sig,siginfo_t * info,void * ctx)46 rtmin_handler (int sig, siginfo_t *info, void *ctx)
47 {
48   if (sig != SIGRTMIN)
49     abort ();
50   ++rtmin_cnt;
51   rtmin_pid = info->si_pid;
52   rtmin_uid = info->si_uid;
53   rtmin_code = info->si_code;
54   rtmin_sigval = info->si_value;
55 }
56 
57 #define mqsend(q) (mqsend) (q, __LINE__)
58 static int
59 (mqsend) (mqd_t q, int line)
60 {
61   char c;
62   if (mq_send (q, &c, 1, 1) != 0)
63     {
64       printf ("mq_send on line %d failed with: %m\n", line);
65       return 1;
66     }
67   return 0;
68 }
69 
70 #define mqrecv(q) (mqrecv) (q, __LINE__)
71 static int
72 (mqrecv) (mqd_t q, int line)
73 {
74   char c;
75   ssize_t rets = TEMP_FAILURE_RETRY (mq_receive (q, &c, 1, NULL));
76   if (rets != 1)
77     {
78       if (rets == -1)
79 	printf ("mq_receive on line %d failed with: %m\n", line);
80       else
81 	printf ("mq_receive on line %d returned %zd != 1\n",
82 		line, rets);
83       return 1;
84     }
85   return 0;
86 }
87 
88 struct thr_data
89 {
90   const char *name;
91   pthread_barrier_t *b3;
92   mqd_t q;
93 };
94 
95 static void *
thr(void * arg)96 thr (void *arg)
97 {
98   pthread_barrier_t *b3 = ((struct thr_data *)arg)->b3;
99   mqd_t q = ((struct thr_data *)arg)->q;
100   const char *name = ((struct thr_data *)arg)->name;
101   int result = 0;
102 
103   result |= mqrecv (q);
104 
105   (void) pthread_barrier_wait (b3);
106 
107   /* Child verifies SIGRTMIN has not been sent.  */
108 
109   (void) pthread_barrier_wait (b3);
110 
111   /* Parent calls mqsend (q), which should trigger notification.  */
112 
113   (void) pthread_barrier_wait (b3);
114 
115   if (rtmin_cnt != 2)
116     {
117       puts ("SIGRTMIN signal in thread did not arrive");
118       result = 1;
119     }
120   else if (rtmin_pid != getppid ()
121 	   || rtmin_uid != getuid ()
122 	   || rtmin_code != SI_MESGQ
123 	   || rtmin_sigval.sival_int != 0xdeadbeef)
124     {
125       printf ("unexpected siginfo_t fields: pid %u (%u), uid %u (%u), code %d (%d), si_int %d (%d)\n",
126 	      rtmin_pid, getppid (), rtmin_uid, getuid (),
127 	      rtmin_code, SI_MESGQ, rtmin_sigval.sival_int, 0xdeadbeef);
128       result = 1;
129     }
130 
131   struct sigevent ev;
132   memset (&ev, 0x82, sizeof (ev));
133   ev.sigev_notify = SIGEV_NONE;
134   if (mq_notify (q, &ev) != 0)
135     {
136       printf ("mq_notify in thread (q, { SIGEV_NONE }) failed with: %m\n");
137       result = 1;
138     }
139 
140   if (mq_notify (q, NULL) != 0)
141     {
142       printf ("mq_notify in thread (q, NULL) failed with: %m\n");
143       result = 1;
144     }
145 
146   result |= mqrecv (q);
147 
148   (void) pthread_barrier_wait (b3);
149 
150   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
151 
152   (void) pthread_barrier_wait (b3);
153 
154   if (mq_notify (q, NULL) != 0)
155     {
156       printf ("second mq_notify in thread (q, NULL) failed with: %m\n");
157       result = 1;
158     }
159 
160   (void) pthread_barrier_wait (b3);
161 
162   /* Parent calls mqsend (q), which should not trigger notification.  */
163 
164   (void) pthread_barrier_wait (b3);
165 
166   /* Child verifies SIGRTMIN has not been received.  */
167   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
168 
169   (void) pthread_barrier_wait (b3);
170 
171   mqd_t q4 = mq_open (name, O_RDONLY);
172   if (q4 == (mqd_t) -1)
173     {
174       printf ("mq_open in thread failed with: %m\n");
175       result = 1;
176     }
177 
178   if (mq_notify (q4, NULL) != 0)
179     {
180       printf ("mq_notify in thread (q4, NULL) failed with: %m\n");
181       result = 1;
182     }
183 
184   if (mq_close (q4) != 0)
185     {
186       printf ("mq_close in thread failed with: %m\n");
187       result = 1;
188     }
189 
190   (void) pthread_barrier_wait (b3);
191 
192   /* Parent calls mqsend (q), which should not trigger notification.  */
193 
194   (void) pthread_barrier_wait (b3);
195 
196   /* Child verifies SIGRTMIN has not been received.  */
197   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
198 
199   (void) pthread_barrier_wait (b3);
200 
201   mqd_t q5 = mq_open (name, O_WRONLY);
202   if (q5 == (mqd_t) -1)
203     {
204       printf ("mq_open O_WRONLY in thread failed with: %m\n");
205       result = 1;
206     }
207 
208   if (mq_notify (q5, NULL) != 0)
209     {
210       printf ("mq_notify in thread (q5, NULL) failed with: %m\n");
211       result = 1;
212     }
213 
214   if (mq_close (q5) != 0)
215     {
216       printf ("mq_close in thread failed with: %m\n");
217       result = 1;
218     }
219 
220   (void) pthread_barrier_wait (b3);
221 
222   /* Parent calls mqsend (q), which should not trigger notification.  */
223 
224   (void) pthread_barrier_wait (b3);
225 
226   /* Child verifies SIGRTMIN has not been received.  */
227 
228   return (void *) (long) result;
229 }
230 
231 static void
do_child(const char * name,pthread_barrier_t * b2,pthread_barrier_t * b3,mqd_t q)232 do_child (const char *name, pthread_barrier_t *b2, pthread_barrier_t *b3,
233 	  mqd_t q)
234 {
235   int result = 0;
236 
237   struct sigevent ev;
238   memset (&ev, 0x55, sizeof (ev));
239   ev.sigev_notify = SIGEV_SIGNAL;
240   ev.sigev_signo = SIGRTMIN;
241   ev.sigev_value.sival_ptr = &ev;
242   if (mq_notify (q, &ev) == 0)
243     {
244       puts ("first mq_notify in child (q, { SIGEV_SIGNAL }) unexpectedly succeeded");
245       result = 1;
246     }
247   else if (errno != EBUSY)
248     {
249       printf ("first mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
250       result = 1;
251     }
252 
253   (void) pthread_barrier_wait (b2);
254 
255   /* Parent calls mqsend (q), which makes notification available.  */
256 
257   (void) pthread_barrier_wait (b2);
258 
259   rtmin_cnt = 0;
260 
261   if (mq_notify (q, &ev) != 0)
262     {
263       printf ("second mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
264       result = 1;
265     }
266 
267   if (rtmin_cnt != 0)
268     {
269       puts ("SIGRTMIN signal in child caught too early");
270       result = 1;
271     }
272 
273   (void) pthread_barrier_wait (b2);
274 
275   /* Parent unsuccessfully attempts to mq_notify.  */
276   /* Parent calls mqsend (q), which makes notification available
277      and triggers a signal in the child.  */
278   /* Parent successfully calls mq_notify SIGEV_SIGNAL.  */
279 
280   (void) pthread_barrier_wait (b2);
281 
282   if (rtmin_cnt != 1)
283     {
284       puts ("SIGRTMIN signal in child did not arrive");
285       result = 1;
286     }
287   else if (rtmin_pid != getppid ()
288 	   || rtmin_uid != getuid ()
289 	   || rtmin_code != SI_MESGQ
290 	   || rtmin_sigval.sival_ptr != &ev)
291     {
292       printf ("unexpected siginfo_t fields: pid %u (%u), uid %u (%u), code %d (%d), si_ptr %p (%p)\n",
293 	      rtmin_pid, getppid (), rtmin_uid, getuid (),
294 	      rtmin_code, SI_MESGQ, rtmin_sigval.sival_ptr, &ev);
295       result = 1;
296     }
297 
298   result |= mqsend (q);
299 
300   (void) pthread_barrier_wait (b2);
301 
302   /* Parent verifies caught SIGRTMIN.  */
303 
304   mqd_t q2 = mq_open (name, O_RDWR);
305   if (q2 == (mqd_t) -1)
306     {
307       printf ("mq_open in child failed with: %m\n");
308       result = 1;
309     }
310 
311   (void) pthread_barrier_wait (b2);
312 
313   /* Parent mq_open's another mqd_t for the same queue (q3).  */
314 
315   memset (&ev, 0x11, sizeof (ev));
316   ev.sigev_notify = SIGEV_SIGNAL;
317   ev.sigev_signo = SIGRTMIN;
318   ev.sigev_value.sival_ptr = &ev;
319   if (mq_notify (q2, &ev) != 0)
320     {
321       printf ("mq_notify in child (q2, { SIGEV_SIGNAL }) failed with: %m\n");
322       result = 1;
323     }
324 
325   (void) pthread_barrier_wait (b2);
326 
327   /* Parent unsuccessfully attempts to mq_notify { SIGEV_NONE } on q.  */
328 
329   (void) pthread_barrier_wait (b2);
330 
331   if (mq_close (q2) != 0)
332     {
333       printf ("mq_close failed: %m\n");
334       result = 1;
335     }
336 
337   (void) pthread_barrier_wait (b2);
338 
339   /* Parent successfully calls mq_notify { SIGEV_NONE } on q3.  */
340 
341   (void) pthread_barrier_wait (b2);
342 
343   memset (&ev, 0xbb, sizeof (ev));
344   ev.sigev_notify = SIGEV_SIGNAL;
345   ev.sigev_signo = SIGRTMIN;
346   ev.sigev_value.sival_ptr = &b2;
347   if (mq_notify (q, &ev) == 0)
348     {
349       puts ("third mq_notify in child (q, { SIGEV_SIGNAL }) unexpectedly succeeded");
350       result = 1;
351     }
352   else if (errno != EBUSY)
353     {
354       printf ("third mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
355       result = 1;
356     }
357 
358   (void) pthread_barrier_wait (b2);
359 
360   /* Parent calls mq_close on q3, which makes the queue available again for
361      notification.  */
362 
363   (void) pthread_barrier_wait (b2);
364 
365   memset (&ev, 0x13, sizeof (ev));
366   ev.sigev_notify = SIGEV_NONE;
367   if (mq_notify (q, &ev) != 0)
368     {
369       printf ("mq_notify in child (q, { SIGEV_NONE }) failed with: %m\n");
370       result = 1;
371     }
372 
373   if (mq_notify (q, NULL) != 0)
374     {
375       printf ("mq_notify in child (q, NULL) failed with: %m\n");
376       result = 1;
377     }
378 
379   (void) pthread_barrier_wait (b2);
380 
381   struct thr_data thr_data = { .name = name, .b3 = b3, .q = q };
382   pthread_t th;
383   int ret = pthread_create (&th, NULL, thr, &thr_data);
384   if (ret)
385     {
386       errno = ret;
387       printf ("pthread_created failed with: %m\n");
388       result = 1;
389     }
390 
391   /* Wait till thr calls mq_receive on the empty queue q and blocks on it.  */
392   sleep (1);
393 
394   memset (&ev, 0x5f, sizeof (ev));
395   ev.sigev_notify = SIGEV_SIGNAL;
396   ev.sigev_signo = SIGRTMIN;
397   ev.sigev_value.sival_int = 0xdeadbeef;
398   if (mq_notify (q, &ev) != 0)
399     {
400       printf ("fourth mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
401       result = 1;
402     }
403 
404   /* Ensure the thr thread gets the signal, not us.  */
405   sigset_t set;
406   sigemptyset (&set);
407   sigaddset (&set, SIGRTMIN);
408   if (pthread_sigmask (SIG_BLOCK, &set, NULL))
409     {
410       printf ("Failed to block SIGRTMIN in child: %m\n");
411       result = 1;
412     }
413 
414   (void) pthread_barrier_wait (b2);
415 
416   /* Parent calls mqsend (q), which should wake up mqrecv (q)
417      in the thread but no notification should be sent.  */
418 
419   (void) pthread_barrier_wait (b3);
420 
421   if (rtmin_cnt != 1)
422     {
423       puts ("SIGRTMIN signal caught while thr was blocked on mq_receive");
424       result = 1;
425     }
426 
427   (void) pthread_barrier_wait (b3);
428 
429   /* Parent calls mqsend (q), which should trigger notification.  */
430 
431   (void) pthread_barrier_wait (b3);
432 
433   /* Thread verifies SIGRTMIN has been received.  */
434   /* Thread calls mq_notify (q, { SIGEV_NONE }) to verify notification is now
435      available for registration.  */
436   /* Thread calls mq_notify (q, NULL).  */
437 
438   (void) pthread_barrier_wait (b3);
439 
440   memset (&ev, 0x6a, sizeof (ev));
441   ev.sigev_notify = SIGEV_SIGNAL;
442   ev.sigev_signo = SIGRTMIN;
443   ev.sigev_value.sival_ptr = do_child;
444   if (mq_notify (q, &ev) != 0)
445     {
446       printf ("fifth mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
447       result = 1;
448     }
449 
450   (void) pthread_barrier_wait (b3);
451 
452   /* Thread calls mq_notify (q, NULL), which should unregister the above
453      notification.  */
454 
455   (void) pthread_barrier_wait (b3);
456 
457   /* Parent calls mqsend (q), which should not trigger notification.  */
458 
459   (void) pthread_barrier_wait (b3);
460 
461   if (rtmin_cnt != 2)
462     {
463       puts ("SIGRTMIN signal caught while notification has been disabled");
464       result = 1;
465     }
466 
467   memset (&ev, 0x7b, sizeof (ev));
468   ev.sigev_notify = SIGEV_SIGNAL;
469   ev.sigev_signo = SIGRTMIN;
470   ev.sigev_value.sival_ptr = thr;
471   if (mq_notify (q, &ev) != 0)
472     {
473       printf ("sixth mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
474       result = 1;
475     }
476 
477   (void) pthread_barrier_wait (b3);
478 
479   /* Thread opens a new O_RDONLY mqd_t (q4).  */
480   /* Thread calls mq_notify (q4, NULL), which should unregister the above
481      notification.  */
482   /* Thread calls mq_close (q4).  */
483 
484   (void) pthread_barrier_wait (b3);
485 
486   /* Parent calls mqsend (q), which should not trigger notification.  */
487 
488   (void) pthread_barrier_wait (b3);
489 
490   if (rtmin_cnt != 2)
491     {
492       puts ("SIGRTMIN signal caught while notification has been disabled");
493       result = 1;
494     }
495 
496   memset (&ev, 0xe1, sizeof (ev));
497   ev.sigev_notify = SIGEV_SIGNAL;
498   ev.sigev_signo = SIGRTMIN;
499   ev.sigev_value.sival_int = 127;
500   if (mq_notify (q, &ev) != 0)
501     {
502       printf ("seventh mq_notify in child (q, { SIGEV_SIGNAL }) failed with: %m\n");
503       result = 1;
504     }
505 
506   (void) pthread_barrier_wait (b3);
507 
508   /* Thread opens a new O_WRONLY mqd_t (q5).  */
509   /* Thread calls mq_notify (q5, NULL), which should unregister the above
510      notification.  */
511   /* Thread calls mq_close (q5).  */
512 
513   (void) pthread_barrier_wait (b3);
514 
515   /* Parent calls mqsend (q), which should not trigger notification.  */
516 
517   (void) pthread_barrier_wait (b3);
518 
519   if (rtmin_cnt != 2)
520     {
521       puts ("SIGRTMIN signal caught while notification has been disabled");
522       result = 1;
523     }
524 
525   /* Reenable test signals before cleaning up the thread.  */
526   if (pthread_sigmask (SIG_UNBLOCK, &set, NULL))
527     {
528       printf ("Failed to unblock SIGRTMIN in child: %m\n");
529       result = 1;
530     }
531 
532   void *thr_ret;
533   ret = pthread_join (th, &thr_ret);
534   if (ret)
535     {
536       errno = ret;
537       printf ("pthread_join failed: %m\n");
538       result = 1;
539     }
540   else if (thr_ret)
541     result = 1;
542 
543   if (mq_close (q) != 0)
544     {
545       printf ("mq_close failed: %m\n");
546       result = 1;
547     }
548 
549   exit (result);
550 }
551 
552 #define TEST_FUNCTION do_test ()
553 static int
do_test(void)554 do_test (void)
555 {
556   int result = 0;
557 
558   char tmpfname[] = "/tmp/tst-mqueue5-barrier.XXXXXX";
559   int fd = mkstemp (tmpfname);
560   if (fd == -1)
561     {
562       printf ("cannot open temporary file: %m\n");
563       return 1;
564     }
565 
566   /* Make sure it is always removed.  */
567   unlink (tmpfname);
568 
569   /* Create one page of data.  */
570   size_t ps = sysconf (_SC_PAGESIZE);
571   char data[ps];
572   memset (data, '\0', ps);
573 
574   /* Write the data to the file.  */
575   if (write (fd, data, ps) != (ssize_t) ps)
576     {
577       puts ("short write");
578       return 1;
579     }
580 
581   void *mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
582   if (mem == MAP_FAILED)
583     {
584       printf ("mmap failed: %m\n");
585       return 1;
586     }
587 
588   pthread_barrier_t *b2;
589   b2 = (pthread_barrier_t *) (((uintptr_t) mem + __alignof (pthread_barrier_t))
590 			      & ~(__alignof (pthread_barrier_t) - 1));
591 
592   pthread_barrier_t *b3;
593   b3 = b2 + 1;
594 
595   pthread_barrierattr_t a;
596   if (pthread_barrierattr_init (&a) != 0)
597     {
598       puts ("barrierattr_init failed");
599       return 1;
600     }
601 
602   if (pthread_barrierattr_setpshared (&a, PTHREAD_PROCESS_SHARED) != 0)
603     {
604       puts ("barrierattr_setpshared failed, could not test");
605       return 0;
606     }
607 
608   if (pthread_barrier_init (b2, &a, 2) != 0)
609     {
610       puts ("barrier_init failed");
611       return 1;
612     }
613 
614   if (pthread_barrier_init (b3, &a, 3) != 0)
615     {
616       puts ("barrier_init failed");
617       return 1;
618     }
619 
620   if (pthread_barrierattr_destroy (&a) != 0)
621     {
622       puts ("barrierattr_destroy failed");
623       return 1;
624     }
625 
626   char name[sizeof "/tst-mqueue5-" + sizeof (pid_t) * 3];
627   snprintf (name, sizeof (name), "/tst-mqueue5-%u", getpid ());
628 
629   struct mq_attr attr = { .mq_maxmsg = 1, .mq_msgsize = 1 };
630   mqd_t q = mq_open (name, O_CREAT | O_EXCL | O_RDWR, 0600, &attr);
631 
632   if (q == (mqd_t) -1)
633     {
634       if (errno == ENOSYS)
635 	FAIL_UNSUPPORTED ("mq_open not supported");
636 
637       printf ("mq_open failed with: %m\n");
638       return 1;
639     }
640 
641   add_temp_mq (name);
642 
643   struct sigevent ev;
644   memset (&ev, 0xaa, sizeof (ev));
645   ev.sigev_notify = SIGEV_NONE;
646   if (mq_notify (q, &ev) != 0)
647     {
648       printf ("mq_notify (q, { SIGEV_NONE }) failed with: %m\n");
649       result = 1;
650     }
651 
652   if (mq_notify (q, &ev) == 0)
653     {
654       puts ("second mq_notify (q, { SIGEV_NONE }) unexpectedly succeeded");
655       result = 1;
656     }
657   else if (errno != EBUSY)
658     {
659       printf ("second mq_notify (q, { SIGEV_NONE }) failed with: %m\n");
660       result = 1;
661     }
662 
663   result |= mqsend (q);
664 
665   if (mq_notify (q, &ev) != 0)
666     {
667       printf ("third mq_notify (q, { SIGEV_NONE }) failed with: %m\n");
668       result = 1;
669     }
670 
671   result |= mqrecv (q);
672 
673   if (mq_notify (q, NULL) != 0)
674     {
675       printf ("mq_notify (q, NULL) failed with: %m\n");
676       result = 1;
677     }
678 
679   if (mq_notify (q, NULL) != 0)
680     {
681       /* Implementation-defined behaviour, so don't fail,
682 	 just inform.  */
683       printf ("second mq_notify (q, NULL) failed with: %m\n");
684     }
685 
686   struct sigaction sa = { .sa_sigaction = rtmin_handler,
687 			  .sa_flags = SA_SIGINFO };
688   sigemptyset (&sa.sa_mask);
689   sigaction (SIGRTMIN, &sa, NULL);
690 
691   memset (&ev, 0x55, sizeof (ev));
692   ev.sigev_notify = SIGEV_SIGNAL;
693   ev.sigev_signo = SIGRTMIN;
694   ev.sigev_value.sival_int = 26;
695   if (mq_notify (q, &ev) != 0)
696     {
697       printf ("mq_notify (q, { SIGEV_SIGNAL }) failed with: %m\n");
698       result = 1;
699     }
700 
701   ev.sigev_value.sival_ptr = &ev;
702   if (mq_notify (q, &ev) == 0)
703     {
704       puts ("second mq_notify (q, { SIGEV_SIGNAL }) unexpectedly succeeded");
705       result = 1;
706     }
707   else if (errno != EBUSY)
708     {
709       printf ("second mq_notify (q, { SIGEV_SIGNAL }) failed with: %m\n");
710       result = 1;
711     }
712 
713   if (rtmin_cnt != 0)
714     {
715       puts ("SIGRTMIN signal caught too early");
716       result = 1;
717     }
718 
719   result |= mqsend (q);
720 
721   if (rtmin_cnt != 1)
722     {
723       puts ("SIGRTMIN signal did not arrive");
724       result = 1;
725     }
726   else if (rtmin_pid != getpid ()
727 	   || rtmin_uid != getuid ()
728 	   || rtmin_code != SI_MESGQ
729 	   || rtmin_sigval.sival_int != 26)
730     {
731       printf ("unexpected siginfo_t fields: pid %u (%u), uid %u (%u), code %d (%d), si_int %d (26)\n",
732 	      rtmin_pid, getpid (), rtmin_uid, getuid (),
733 	      rtmin_code, SI_MESGQ, rtmin_sigval.sival_int);
734       result = 1;
735     }
736 
737   ev.sigev_value.sival_int = 75;
738   if (mq_notify (q, &ev) != 0)
739     {
740       printf ("third mq_notify (q, { SIGEV_SIGNAL }) failed with: %m\n");
741       result = 1;
742     }
743 
744   result |= mqrecv (q);
745 
746   if (mq_notify (q, NULL) != 0)
747     {
748       printf ("mq_notify (q, NULL) failed with: %m\n");
749       result = 1;
750     }
751 
752   memset (&ev, 0x33, sizeof (ev));
753   ev.sigev_notify = SIGEV_NONE;
754   if (mq_notify (q, &ev) != 0)
755     {
756       printf ("fourth mq_notify (q, { SIGEV_NONE }) failed with: %m\n");
757       result = 1;
758     }
759 
760   pid_t pid = fork ();
761   if (pid == -1)
762     {
763       printf ("fork () failed: %m\n");
764       mq_unlink (name);
765       return 1;
766     }
767 
768   if (pid == 0)
769     do_child (name, b2, b3, q);
770 
771   /* Child unsuccessfully attempts to mq_notify.  */
772 
773   (void) pthread_barrier_wait (b2);
774 
775   result |= mqsend (q);
776 
777   (void) pthread_barrier_wait (b2);
778 
779   /* Child successfully calls mq_notify SIGEV_SIGNAL now.  */
780 
781   result |= mqrecv (q);
782 
783   (void) pthread_barrier_wait (b2);
784 
785   memset (&ev, 0xbb, sizeof (ev));
786   ev.sigev_notify = SIGEV_SIGNAL;
787   ev.sigev_signo = SIGRTMIN;
788   ev.sigev_value.sival_int = 15;
789   if (mq_notify (q, &ev) == 0)
790     {
791       puts ("fourth mq_notify (q, { SIGEV_SIGNAL }) unexpectedly succeeded");
792       result = 1;
793     }
794   else if (errno != EBUSY)
795     {
796       printf ("fourth mq_notify (q, { SIGEV_SIGNAL }) failed with: %m\n");
797       result = 1;
798     }
799 
800   result |= mqsend (q);
801 
802   if (mq_notify (q, &ev) != 0)
803     {
804       printf ("fifth mq_notify (q, { SIGEV_SIGNAL }) failed with: %m\n");
805       result = 1;
806     }
807 
808   if (rtmin_cnt != 1)
809     {
810       puts ("SIGRTMIN signal caught too early");
811       result = 1;
812     }
813 
814   result |= mqrecv (q);
815 
816   (void) pthread_barrier_wait (b2);
817 
818   /* Child verifies caught SIGRTMIN signal.  */
819   /* Child calls mq_send (q) which triggers SIGRTMIN signal here.  */
820 
821   (void) pthread_barrier_wait (b2);
822 
823   /* Child mq_open's another mqd_t for the same queue (q2).  */
824 
825   if (rtmin_cnt != 2)
826     {
827       puts ("SIGRTMIN signal did not arrive");
828       result = 1;
829     }
830   else if (rtmin_pid != pid
831 	   || rtmin_uid != getuid ()
832 	   || rtmin_code != SI_MESGQ
833 	   || rtmin_sigval.sival_int != 15)
834     {
835       printf ("unexpected siginfo_t fields: pid %u (%u), uid %u (%u), code %d (%d), si_int %d (15)\n",
836 	      rtmin_pid, pid, rtmin_uid, getuid (),
837 	      rtmin_code, SI_MESGQ, rtmin_sigval.sival_int);
838       result = 1;
839     }
840 
841   result |= mqrecv (q);
842 
843   (void) pthread_barrier_wait (b2);
844 
845   /* Child successfully calls mq_notify { SIGEV_SIGNAL } on q2.  */
846 
847   (void) pthread_barrier_wait (b2);
848 
849   memset (&ev, 0xbb, sizeof (ev));
850   ev.sigev_notify = SIGEV_NONE;
851   if (mq_notify (q, &ev) == 0)
852     {
853       puts ("fifth mq_notify (q, { SIGEV_NONE }) unexpectedly succeeded");
854       result = 1;
855     }
856   else if (errno != EBUSY)
857     {
858       printf ("fifth mq_notify (q, { SIGEV_NONE }) failed with: %m\n");
859       result = 1;
860     }
861 
862   (void) pthread_barrier_wait (b2);
863 
864   /* Child calls mq_close on q2, which makes the queue available again for
865      notification.  */
866 
867   mqd_t q3 = mq_open (name, O_RDWR);
868   if (q3 == (mqd_t) -1)
869     {
870       printf ("mq_open q3 in parent failed with: %m\n");
871       result = 1;
872     }
873 
874   (void) pthread_barrier_wait (b2);
875 
876   memset (&ev, 0x12, sizeof (ev));
877   ev.sigev_notify = SIGEV_NONE;
878   if (mq_notify (q3, &ev) != 0)
879     {
880       printf ("mq_notify (q3, { SIGEV_NONE }) failed with: %m\n");
881       result = 1;
882     }
883 
884   (void) pthread_barrier_wait (b2);
885 
886   /* Child unsuccessfully attempts to mq_notify { SIGEV_SIGNAL } on q.  */
887 
888   (void) pthread_barrier_wait (b2);
889 
890   if (mq_close (q3) != 0)
891     {
892       printf ("mq_close failed: %m\n");
893       result = 1;
894     }
895 
896   (void) pthread_barrier_wait (b2);
897 
898   /* Child successfully calls mq_notify { SIGEV_NONE } on q.  */
899   /* Child successfully calls mq_notify NULL on q.  */
900 
901   (void) pthread_barrier_wait (b2);
902 
903   /* Child creates new thread.  */
904   /* Thread blocks on mqrecv (q).  */
905   /* Child sleeps for 1sec so that thread has time to reach that point.  */
906   /* Child successfully calls mq_notify { SIGEV_SIGNAL } on q.  */
907 
908   (void) pthread_barrier_wait (b2);
909 
910   result |= mqsend (q);
911 
912   (void) pthread_barrier_wait (b3);
913 
914   /* Child verifies SIGRTMIN has not been sent.  */
915 
916   (void) pthread_barrier_wait (b3);
917 
918   result |= mqsend (q);
919 
920   (void) pthread_barrier_wait (b3);
921 
922   /* Thread verifies SIGRTMIN has been caught.  */
923   /* Thread calls mq_notify (q, { SIGEV_NONE }) to verify notification is now
924      available for registration.  */
925   /* Thread calls mq_notify (q, NULL).  */
926 
927   (void) pthread_barrier_wait (b3);
928 
929   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
930 
931   (void) pthread_barrier_wait (b3);
932 
933   /* Thread calls mq_notify (q, NULL). */
934 
935   (void) pthread_barrier_wait (b3);
936 
937   result |= mqsend (q);
938   result |= mqrecv (q);
939 
940   (void) pthread_barrier_wait (b3);
941 
942   /* Child verifies SIGRTMIN has not been sent.  */
943   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
944 
945   (void) pthread_barrier_wait (b3);
946 
947   /* Thread opens a new O_RDONLY mqd_t (q4).  */
948   /* Thread calls mq_notify (q4, NULL). */
949   /* Thread calls mq_close (q4).  */
950 
951   (void) pthread_barrier_wait (b3);
952 
953   result |= mqsend (q);
954   result |= mqrecv (q);
955 
956   (void) pthread_barrier_wait (b3);
957 
958   /* Child verifies SIGRTMIN has not been sent.  */
959   /* Child calls mq_notify (q, { SIGEV_SIGNAL }).  */
960 
961   (void) pthread_barrier_wait (b3);
962 
963   /* Thread opens a new O_WRONLY mqd_t (q5).  */
964   /* Thread calls mq_notify (q5, NULL). */
965   /* Thread calls mq_close (q5).  */
966 
967   (void) pthread_barrier_wait (b3);
968 
969   result |= mqsend (q);
970   result |= mqrecv (q);
971 
972   (void) pthread_barrier_wait (b3);
973 
974   /* Child verifies SIGRTMIN has not been sent.  */
975 
976   int status;
977   if (TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)) != pid)
978     {
979       puts ("waitpid failed");
980       kill (pid, SIGKILL);
981       result = 1;
982     }
983   else if (!WIFEXITED (status) || WEXITSTATUS (status))
984     {
985       printf ("child failed with status %d\n", status);
986       result = 1;
987     }
988 
989   if (mq_unlink (name) != 0)
990     {
991       printf ("mq_unlink failed: %m\n");
992       result = 1;
993     }
994 
995   if (mq_close (q) != 0)
996     {
997       printf ("mq_close failed: %m\n");
998       result = 1;
999     }
1000 
1001   if (mq_notify (q, NULL) == 0)
1002     {
1003       puts ("mq_notify on closed mqd_t unexpectedly succeeded");
1004       result = 1;
1005     }
1006   else if (errno != EBADF)
1007     {
1008       printf ("mq_notify on closed mqd_t did not fail with EBADF: %m\n");
1009       result = 1;
1010     }
1011 
1012   memset (&ev, 0x55, sizeof (ev));
1013   ev.sigev_notify = SIGEV_NONE;
1014   if (mq_notify (q, &ev) == 0)
1015     {
1016       puts ("mq_notify on closed mqd_t unexpectedly succeeded");
1017       result = 1;
1018     }
1019   else if (errno != EBADF)
1020     {
1021       printf ("mq_notify on closed mqd_t did not fail with EBADF: %m\n");
1022       result = 1;
1023     }
1024 
1025   return result;
1026 }
1027 #else
1028 # define TEST_FUNCTION 0
1029 #endif
1030 
1031 #include "../test-skeleton.c"
1032