1 /*-
2 * Copyright (c) 1990, 1993, 1995
3 * The Regents of the University of California.
4 * Copyright (c) 2005 Robert N. M. Watson
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 4. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)fifo_vnops.c 8.10 (Berkeley) 5/27/95
32 * $FreeBSD$
33 */
34
35 #include <sys/param.h>
36 #include <sys/event.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 #include <sys/filio.h>
40 #include <sys/fcntl.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/malloc.h>
45 #include <sys/poll.h>
46 #include <sys/proc.h> /* XXXKSE */
47 #include <sys/signalvar.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/sx.h>
51 #include <sys/systm.h>
52 #include <sys/un.h>
53 #include <sys/unistd.h>
54 #include <sys/vnode.h>
55 #include <fs/fifofs/fifo.h>
56
57 static fo_rdwr_t fifo_read_f;
58 static fo_rdwr_t fifo_write_f;
59 static fo_ioctl_t fifo_ioctl_f;
60 static fo_poll_t fifo_poll_f;
61 static fo_kqfilter_t fifo_kqfilter_f;
62 static fo_stat_t fifo_stat_f;
63 static fo_close_t fifo_close_f;
64
65 struct fileops fifo_ops_f = {
66 .fo_read = fifo_read_f,
67 .fo_write = fifo_write_f,
68 .fo_ioctl = fifo_ioctl_f,
69 .fo_poll = fifo_poll_f,
70 .fo_kqfilter = fifo_kqfilter_f,
71 .fo_stat = fifo_stat_f,
72 .fo_close = fifo_close_f,
73 .fo_flags = DFLAG_PASSABLE
74 };
75
76 /*
77 * This structure is associated with the FIFO vnode and stores
78 * the state associated with the FIFO.
79 */
80 struct fifoinfo {
81 struct socket *fi_readsock;
82 struct socket *fi_writesock;
83 long fi_readers;
84 long fi_writers;
85 };
86
87 static vop_print_t fifo_print;
88 static vop_open_t fifo_open;
89 static vop_close_t fifo_close;
90 static vop_ioctl_t fifo_ioctl;
91 static vop_kqfilter_t fifo_kqfilter;
92 static vop_pathconf_t fifo_pathconf;
93 static vop_advlock_t fifo_advlock;
94
95 static void filt_fifordetach(struct knote *kn);
96 static int filt_fiforead(struct knote *kn, long hint);
97 static void filt_fifowdetach(struct knote *kn);
98 static int filt_fifowrite(struct knote *kn, long hint);
99 static void filt_fifodetach_notsup(struct knote *kn);
100 static int filt_fifo_notsup(struct knote *kn, long hint);
101
102 static struct filterops fiforead_filtops =
103 { 1, NULL, filt_fifordetach, filt_fiforead };
104 static struct filterops fifowrite_filtops =
105 { 1, NULL, filt_fifowdetach, filt_fifowrite };
106 static struct filterops fifo_notsup_filtops =
107 { 1, NULL, filt_fifodetach_notsup, filt_fifo_notsup };
108
109 struct vop_vector fifo_specops = {
110 .vop_default = &default_vnodeops,
111
112 .vop_access = VOP_EBADF,
113 .vop_advlock = fifo_advlock,
114 .vop_close = fifo_close,
115 .vop_create = VOP_PANIC,
116 .vop_getattr = VOP_EBADF,
117 .vop_ioctl = fifo_ioctl,
118 .vop_kqfilter = fifo_kqfilter,
119 .vop_lease = VOP_NULL,
120 .vop_link = VOP_PANIC,
121 .vop_mkdir = VOP_PANIC,
122 .vop_mknod = VOP_PANIC,
123 .vop_open = fifo_open,
124 .vop_pathconf = fifo_pathconf,
125 .vop_print = fifo_print,
126 .vop_read = VOP_PANIC,
127 .vop_readdir = VOP_PANIC,
128 .vop_readlink = VOP_PANIC,
129 .vop_reallocblks = VOP_PANIC,
130 .vop_reclaim = VOP_NULL,
131 .vop_remove = VOP_PANIC,
132 .vop_rename = VOP_PANIC,
133 .vop_rmdir = VOP_PANIC,
134 .vop_setattr = VOP_EBADF,
135 .vop_symlink = VOP_PANIC,
136 .vop_write = VOP_PANIC,
137 };
138
139 struct mtx fifo_mtx;
140 MTX_SYSINIT(fifo, &fifo_mtx, "fifo mutex", MTX_DEF);
141
142 /*
143 * Dispose of fifo resources.
144 */
145 static void
146 fifo_cleanup(struct vnode *vp)
147 {
148 struct fifoinfo *fip = vp->v_fifoinfo;
149
150 ASSERT_VOP_LOCKED(vp, "fifo_cleanup");
151 if (fip->fi_readers == 0 && fip->fi_writers == 0) {
152 vp->v_fifoinfo = NULL;
153 (void)soclose(fip->fi_readsock);
154 (void)soclose(fip->fi_writesock);
155 FREE(fip, M_VNODE);
156 }
157 }
158
159 /*
160 * Open called to set up a new instance of a fifo or
161 * to find an active instance of a fifo.
162 */
163 /* ARGSUSED */
164 static int
165 fifo_open(ap)
166 struct vop_open_args /* {
167 struct vnode *a_vp;
168 int a_mode;
169 struct ucred *a_cred;
170 struct thread *a_td;
171 int a_fdidx;
172 } */ *ap;
173 {
174 struct vnode *vp = ap->a_vp;
175 struct fifoinfo *fip;
176 struct thread *td = ap->a_td;
177 struct ucred *cred = ap->a_cred;
178 struct file *fp = ap->a_fp;
179 struct socket *rso, *wso;
180 int error;
181
182 ASSERT_VOP_ELOCKED(vp, "fifo_open");
183 if (fp == NULL)
184 return (EINVAL);
185 if ((fip = vp->v_fifoinfo) == NULL) {
186 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
187 error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0, cred, td);
188 if (error)
189 goto fail1;
190 fip->fi_readsock = rso;
191 error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0, cred, td);
192 if (error)
193 goto fail2;
194 fip->fi_writesock = wso;
195 error = soconnect2(wso, rso);
196 if (error) {
197 (void)soclose(wso);
198 fail2:
199 (void)soclose(rso);
200 fail1:
201 free(fip, M_VNODE);
202 return (error);
203 }
204 fip->fi_readers = fip->fi_writers = 0;
205 wso->so_snd.sb_lowat = PIPE_BUF;
206 SOCKBUF_LOCK(&rso->so_rcv);
207 rso->so_rcv.sb_state |= SBS_CANTRCVMORE;
208 SOCKBUF_UNLOCK(&rso->so_rcv);
209 KASSERT(vp->v_fifoinfo == NULL,
210 ("fifo_open: v_fifoinfo race"));
211 vp->v_fifoinfo = fip;
212 }
213
214 /*
215 * General access to fi_readers and fi_writers is protected using
216 * the vnode lock.
217 *
218 * Protect the increment of fi_readers and fi_writers and the
219 * associated calls to wakeup() with the fifo mutex in addition
220 * to the vnode lock. This allows the vnode lock to be dropped
221 * for the msleep() calls below, and using the fifo mutex with
222 * msleep() prevents the wakeup from being missed.
223 */
224 mtx_lock(&fifo_mtx);
225 if (ap->a_mode & FREAD) {
226 fip->fi_readers++;
227 if (fip->fi_readers == 1) {
228 SOCKBUF_LOCK(&fip->fi_writesock->so_snd);
229 fip->fi_writesock->so_snd.sb_state &= ~SBS_CANTSENDMORE;
230 SOCKBUF_UNLOCK(&fip->fi_writesock->so_snd);
231 if (fip->fi_writers > 0) {
232 wakeup(&fip->fi_writers);
233 sowwakeup(fip->fi_writesock);
234 }
235 }
236 }
237 if (ap->a_mode & FWRITE) {
238 if ((ap->a_mode & O_NONBLOCK) && fip->fi_readers == 0) {
239 mtx_unlock(&fifo_mtx);
240 return (ENXIO);
241 }
242 fip->fi_writers++;
243 if (fip->fi_writers == 1) {
244 SOCKBUF_LOCK(&fip->fi_readsock->so_rcv);
245 fip->fi_readsock->so_rcv.sb_state &= ~SBS_CANTRCVMORE;
246 SOCKBUF_UNLOCK(&fip->fi_readsock->so_rcv);
247 if (fip->fi_readers > 0) {
248 wakeup(&fip->fi_readers);
249 sorwakeup(fip->fi_readsock);
250 }
251 }
252 }
253 if ((ap->a_mode & O_NONBLOCK) == 0) {
254 if ((ap->a_mode & FREAD) && fip->fi_writers == 0) {
255 VOP_UNLOCK(vp, 0, td);
256 error = msleep(&fip->fi_readers, &fifo_mtx,
257 PDROP | PCATCH | PSOCK, "fifoor", 0);
258 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
259 if (error) {
260 fip->fi_readers--;
261 if (fip->fi_readers == 0) {
262 socantsendmore(fip->fi_writesock);
263 fifo_cleanup(vp);
264 }
265 return (error);
266 }
267 mtx_lock(&fifo_mtx);
268 /*
269 * We must have got woken up because we had a writer.
270 * That (and not still having one) is the condition
271 * that we must wait for.
272 */
273 }
274 if ((ap->a_mode & FWRITE) && fip->fi_readers == 0) {
275 VOP_UNLOCK(vp, 0, td);
276 error = msleep(&fip->fi_writers, &fifo_mtx,
277 PDROP | PCATCH | PSOCK, "fifoow", 0);
278 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
279 if (error) {
280 fip->fi_writers--;
281 if (fip->fi_writers == 0) {
282 socantrcvmore(fip->fi_readsock);
283 fifo_cleanup(vp);
284 }
285 return (error);
286 }
287 /*
288 * We must have got woken up because we had
289 * a reader. That (and not still having one)
290 * is the condition that we must wait for.
291 */
292 mtx_lock(&fifo_mtx);
293 }
294 }
295 mtx_unlock(&fifo_mtx);
296 KASSERT(fp != NULL, ("can't fifo/vnode bypass"));
297 FILE_LOCK(fp);
298 KASSERT(fp->f_ops == &badfileops, ("not badfileops in fifo_open"));
299 fp->f_data = fip;
300 fp->f_ops = &fifo_ops_f;
301 FILE_UNLOCK(fp);
302 return (0);
303 }
304
305 /*
306 * Now unused vnode ioctl routine.
307 */
308 /* ARGSUSED */
309 static int
310 fifo_ioctl(ap)
311 struct vop_ioctl_args /* {
312 struct vnode *a_vp;
313 u_long a_command;
314 caddr_t a_data;
315 int a_fflag;
316 struct ucred *a_cred;
317 struct thread *a_td;
318 } */ *ap;
319 {
320
321 printf("WARNING: fifo_ioctl called unexpectedly\n");
322 return (ENOTTY);
323 }
324
325 /*
326 * Now unused vnode kqfilter routine.
327 */
328 /* ARGSUSED */
329 static int
330 fifo_kqfilter(ap)
331 struct vop_kqfilter_args /* {
332 struct vnode *a_vp;
333 struct knote *a_kn;
334 } */ *ap;
335 {
336
337 printf("WARNING: fifo_kqfilter called unexpectedly\n");
338 return (EINVAL);
339 }
340
341 static void
342 filt_fifordetach(struct knote *kn)
343 {
344 struct socket *so = (struct socket *)kn->kn_hook;
345
346 SOCKBUF_LOCK(&so->so_rcv);
347 knlist_remove(&so->so_rcv.sb_sel.si_note, kn, 1);
348 if (knlist_empty(&so->so_rcv.sb_sel.si_note))
349 so->so_rcv.sb_flags &= ~SB_KNOTE;
350 SOCKBUF_UNLOCK(&so->so_rcv);
351 }
352
353 static int
354 filt_fiforead(struct knote *kn, long hint)
355 {
356 struct socket *so = (struct socket *)kn->kn_hook;
357
358 SOCKBUF_LOCK_ASSERT(&so->so_rcv);
359 kn->kn_data = so->so_rcv.sb_cc;
360 if (so->so_rcv.sb_state & SBS_CANTRCVMORE) {
361 kn->kn_flags |= EV_EOF;
362 return (1);
363 } else {
364 kn->kn_flags &= ~EV_EOF;
365 return (kn->kn_data > 0);
366 }
367 }
368
369 static void
370 filt_fifowdetach(struct knote *kn)
371 {
372 struct socket *so = (struct socket *)kn->kn_hook;
373
374 SOCKBUF_LOCK(&so->so_snd);
375 knlist_remove(&so->so_snd.sb_sel.si_note, kn, 1);
376 if (knlist_empty(&so->so_snd.sb_sel.si_note))
377 so->so_snd.sb_flags &= ~SB_KNOTE;
378 SOCKBUF_UNLOCK(&so->so_snd);
379 }
380
381 static int
382 filt_fifowrite(struct knote *kn, long hint)
383 {
384 struct socket *so = (struct socket *)kn->kn_hook;
385
386 SOCKBUF_LOCK_ASSERT(&so->so_snd);
387 kn->kn_data = sbspace(&so->so_snd);
388 if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
389 kn->kn_flags |= EV_EOF;
390 return (1);
391 } else {
392 kn->kn_flags &= ~EV_EOF;
393 return (kn->kn_data >= so->so_snd.sb_lowat);
394 }
395 }
396
397 static void
398 filt_fifodetach_notsup(struct knote *kn)
399 {
400
401 }
402
403 static int
404 filt_fifo_notsup(struct knote *kn, long hint)
405 {
406
407 return (0);
408 }
409
410 /*
411 * Device close routine
412 */
413 /* ARGSUSED */
414 static int
415 fifo_close(ap)
416 struct vop_close_args /* {
417 struct vnode *a_vp;
418 int a_fflag;
419 struct ucred *a_cred;
420 struct thread *a_td;
421 } */ *ap;
422 {
423 struct vnode *vp = ap->a_vp;
424 struct fifoinfo *fip = vp->v_fifoinfo;
425
426 ASSERT_VOP_LOCKED(vp, "fifo_close");
427 if (fip == NULL) {
428 printf("fifo_close: no v_fifoinfo %p\n", vp);
429 return (0);
430 }
431 if (ap->a_fflag & FREAD) {
432 fip->fi_readers--;
433 if (fip->fi_readers == 0)
434 socantsendmore(fip->fi_writesock);
435 }
436 if (ap->a_fflag & FWRITE) {
437 fip->fi_writers--;
438 if (fip->fi_writers == 0)
439 socantrcvmore(fip->fi_readsock);
440 }
441 fifo_cleanup(vp);
442 return (0);
443 }
444
445 /*
446 * Print out internal contents of a fifo vnode.
447 */
448 int
449 fifo_printinfo(vp)
450 struct vnode *vp;
451 {
452 register struct fifoinfo *fip = vp->v_fifoinfo;
453
454 if (fip == NULL){
455 printf(", NULL v_fifoinfo");
456 return (0);
457 }
458 printf(", fifo with %ld readers and %ld writers",
459 fip->fi_readers, fip->fi_writers);
460 return (0);
461 }
462
463 /*
464 * Print out the contents of a fifo vnode.
465 */
466 static int
467 fifo_print(ap)
468 struct vop_print_args /* {
469 struct vnode *a_vp;
470 } */ *ap;
471 {
472 fifo_printinfo(ap->a_vp);
473 printf("\n");
474 return (0);
475 }
476
477 /*
478 * Return POSIX pathconf information applicable to fifo's.
479 */
480 static int
481 fifo_pathconf(ap)
482 struct vop_pathconf_args /* {
483 struct vnode *a_vp;
484 int a_name;
485 int *a_retval;
486 } */ *ap;
487 {
488
489 switch (ap->a_name) {
490 case _PC_LINK_MAX:
491 *ap->a_retval = LINK_MAX;
492 return (0);
493 case _PC_PIPE_BUF:
494 *ap->a_retval = PIPE_BUF;
495 return (0);
496 case _PC_CHOWN_RESTRICTED:
497 *ap->a_retval = 1;
498 return (0);
499 default:
500 return (EINVAL);
501 }
502 /* NOTREACHED */
503 }
504
505 /*
506 * Fifo advisory byte-level locks.
507 */
508 /* ARGSUSED */
509 static int
510 fifo_advlock(ap)
511 struct vop_advlock_args /* {
512 struct vnode *a_vp;
513 caddr_t a_id;
514 int a_op;
515 struct flock *a_fl;
516 int a_flags;
517 } */ *ap;
518 {
519
520 return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL);
521 }
522
523 static int
524 fifo_close_f(struct file *fp, struct thread *td)
525 {
526
527 return (vnops.fo_close(fp, td));
528 }
529
530 /*
531 * The implementation of ioctl() for named fifos is complicated by the fact
532 * that we permit O_RDWR fifo file descriptors, meaning that the actions of
533 * ioctls may have to be applied to both the underlying sockets rather than
534 * just one. The original implementation simply forward the ioctl to one
535 * or both sockets based on fp->f_flag. We now consider each ioctl
536 * separately, as the composition effect requires careful ordering.
537 *
538 * We do not blindly pass all ioctls through to the socket in order to avoid
539 * providing unnecessary ioctls that might be improperly depended on by
540 * applications (such as socket-specific, routing, and interface ioctls).
541 *
542 * Unlike sys_pipe.c, fifos do not implement the deprecated TIOCSPGRP and
543 * TIOCGPGRP ioctls. Earlier implementations of fifos did forward SIOCSPGRP
544 * and SIOCGPGRP ioctls, so we might need to re-add those here.
545 */
546 static int
547 fifo_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred,
548 struct thread *td)
549 {
550 struct fifoinfo *fi;
551 struct file filetmp; /* Local, so need not be locked. */
552 int error;
553
554 error = ENOTTY;
555 fi = fp->f_data;
556
557 switch (com) {
558 case FIONBIO:
559 /*
560 * Non-blocking I/O is implemented at the fifo layer using
561 * MSG_NBIO, so does not need to be forwarded down the stack.
562 */
563 return (0);
564
565 case FIOASYNC:
566 case FIOSETOWN:
567 case FIOGETOWN:
568 /*
569 * These socket ioctls don't have any ordering requirements,
570 * so are called in an arbitrary order, and only on the
571 * sockets indicated by the file descriptor rights.
572 *
573 * XXXRW: If O_RDWR and the read socket accepts an ioctl but
574 * the write socket doesn't, the socketpair is left in an
575 * inconsistent state.
576 */
577 if (fp->f_flag & FREAD) {
578 filetmp.f_data = fi->fi_readsock;
579 filetmp.f_cred = cred;
580 error = soo_ioctl(&filetmp, com, data, cred, td);
581 if (error)
582 return (error);
583 }
584 if (fp->f_flag & FWRITE) {
585 filetmp.f_data = fi->fi_writesock;
586 filetmp.f_cred = cred;
587 error = soo_ioctl(&filetmp, com, data, cred, td);
588 }
589 return (error);
590
591 case FIONREAD:
592 /*
593 * FIONREAD will return 0 for non-readable descriptors, and
594 * the results of FIONREAD on the read socket for readable
595 * descriptors.
596 */
597 if (!(fp->f_flag & FREAD)) {
598 *(int *)data = 0;
599 return (0);
600 }
601 filetmp.f_data = fi->fi_readsock;
602 filetmp.f_cred = cred;
603 return (soo_ioctl(&filetmp, com, data, cred, td));
604
605 default:
606 return (ENOTTY);
607 }
608 }
609
610 /*
611 * Because fifos are now a file descriptor layer object, EVFILT_VNODE is not
612 * implemented. Likely, fifo_kqfilter() should be removed, and
613 * fifo_kqfilter_f() should know how to forward the request to the underling
614 * vnode using f_vnode in the file descriptor here.
615 */
616 static int
617 fifo_kqfilter_f(struct file *fp, struct knote *kn)
618 {
619 struct fifoinfo *fi;
620 struct socket *so;
621 struct sockbuf *sb;
622
623 fi = fp->f_data;
624
625 /*
626 * If a filter is requested that is not supported by this file
627 * descriptor, don't return an error, but also don't ever generate an
628 * event.
629 */
630 if ((kn->kn_filter == EVFILT_READ) && !(fp->f_flag & FREAD)) {
631 kn->kn_fop = &fifo_notsup_filtops;
632 return (0);
633 }
634
635 if ((kn->kn_filter == EVFILT_WRITE) && !(fp->f_flag & FWRITE)) {
636 kn->kn_fop = &fifo_notsup_filtops;
637 return (0);
638 }
639
640 switch (kn->kn_filter) {
641 case EVFILT_READ:
642 kn->kn_fop = &fiforead_filtops;
643 so = fi->fi_readsock;
644 sb = &so->so_rcv;
645 break;
646 case EVFILT_WRITE:
647 kn->kn_fop = &fifowrite_filtops;
648 so = fi->fi_writesock;
649 sb = &so->so_snd;
650 break;
651 default:
652 return (EINVAL);
653 }
654
655 kn->kn_hook = (caddr_t)so;
656
657 SOCKBUF_LOCK(sb);
658 knlist_add(&sb->sb_sel.si_note, kn, 1);
659 sb->sb_flags |= SB_KNOTE;
660 SOCKBUF_UNLOCK(sb);
661
662 return (0);
663 }
664
665 static int
666 fifo_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td)
667 {
668 struct fifoinfo *fip;
669 struct file filetmp;
670 int levents, revents = 0;
671
672 fip = fp->f_data;
673 levents = events &
674 (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | POLLRDBAND);
675 if ((fp->f_flag & FREAD) && levents) {
676 /*
677 * If POLLIN or POLLRDNORM is requested and POLLINIGNEOF is
678 * not, then convert the first two to the last one. This
679 * tells the socket poll function to ignore EOF so that we
680 * block if there is no writer (and no data). Callers can
681 * set POLLINIGNEOF to get non-blocking behavior.
682 */
683 if (levents & (POLLIN | POLLRDNORM) &&
684 !(levents & POLLINIGNEOF)) {
685 levents &= ~(POLLIN | POLLRDNORM);
686 levents |= POLLINIGNEOF;
687 }
688
689 filetmp.f_data = fip->fi_readsock;
690 filetmp.f_cred = cred;
691 revents |= soo_poll(&filetmp, levents, cred, td);
692
693 /* Reverse the above conversion. */
694 if ((revents & POLLINIGNEOF) && !(events & POLLINIGNEOF)) {
695 revents |= (events & (POLLIN | POLLRDNORM));
696 revents &= ~POLLINIGNEOF;
697 }
698 }
699 levents = events & (POLLOUT | POLLWRNORM | POLLWRBAND);
700 if ((fp->f_flag & FWRITE) && levents) {
701 filetmp.f_data = fip->fi_writesock;
702 filetmp.f_cred = cred;
703 revents |= soo_poll(&filetmp, levents, cred, td);
704 }
705 return (revents);
706 }
707
708 static int
709 fifo_read_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td)
710 {
711 struct fifoinfo *fip;
712 int sflags;
713
714 fip = fp->f_data;
715 KASSERT(uio->uio_rw == UIO_READ,("fifo_read mode"));
716 if (uio->uio_resid == 0)
717 return (0);
718 sflags = (fp->f_flag & FNONBLOCK) ? MSG_NBIO : 0;
719 return (soreceive(fip->fi_readsock, NULL, uio, NULL, NULL, &sflags));
720 }
721
722 static int
723 fifo_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td)
724 {
725
726 return (vnops.fo_stat(fp, sb, cred, td));
727 }
728
729 static int
730 fifo_write_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td)
731 {
732 struct fifoinfo *fip;
733 int sflags;
734
735 fip = fp->f_data;
736 KASSERT(uio->uio_rw == UIO_WRITE,("fifo_write mode"));
737 sflags = (fp->f_flag & FNONBLOCK) ? MSG_NBIO : 0;
738 return (sosend(fip->fi_writesock, NULL, uio, 0, NULL, sflags, td));
739 }
Cache object: b0393a072275737858a76344b277471f
|