[unix-history] / sys / kern / fifo_vnops.c

/*
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)fifo_vnops.c	7.7 (Berkeley) 4/15/91
 *
 * PATCHES MAGIC                LEVEL   PATCH THAT GOT US HERE
 * --------------------         -----   ----------------------
 * CURRENT PATCH LEVEL:         1       00141
 * --------------------         -----   ----------------------
 *
 * 20 Apr 93	Jay Fenlason	1. fi_{readers|fi_writers} of fifoinfo init to 0
 *				2. fifo_open() was calling tsleep() without
 *				unlocking the inode of the fifo
 */

#ifdef	FIFO
#include "param.h"
#include "time.h"
#include "namei.h"
#include "vnode.h"
#include "socket.h"
#include "socketvar.h"
#include "stat.h"
#include "systm.h"
#include "ioctl.h"
#include "file.h"
#include "fifo.h"
#include "errno.h"
#include "malloc.h"

/*
 * This structure is associated with the FIFO vnode and stores
 * the state associated with the FIFO.
 */
struct fifoinfo {
	struct socket	*fi_readsock;
	struct socket	*fi_writesock;
	long		fi_readers;
	long		fi_writers;
};

struct vnodeops fifo_vnodeops = {
	fifo_lookup,		/* lookup */
	fifo_create,		/* create */
	fifo_mknod,		/* mknod */
	fifo_open,		/* open */
	fifo_close,		/* close */
	fifo_access,		/* access */
	fifo_getattr,		/* getattr */
	fifo_setattr,		/* setattr */
	fifo_read,		/* read */
	fifo_write,		/* write */
	fifo_ioctl,		/* ioctl */
	fifo_select,		/* select */
	fifo_mmap,		/* mmap */
	fifo_fsync,		/* fsync */
	fifo_seek,		/* seek */
	fifo_remove,		/* remove */
	fifo_link,		/* link */
	fifo_rename,		/* rename */
	fifo_mkdir,		/* mkdir */
	fifo_rmdir,		/* rmdir */
	fifo_symlink,		/* symlink */
	fifo_readdir,		/* readdir */
	fifo_readlink,		/* readlink */
	fifo_abortop,		/* abortop */
	fifo_inactive,		/* inactive */
	fifo_reclaim,		/* reclaim */
	fifo_lock,		/* lock */
	fifo_unlock,		/* unlock */
	fifo_bmap,		/* bmap */
	fifo_strategy,		/* strategy */
	fifo_print,		/* print */
	fifo_islocked,		/* islocked */
	fifo_advlock,		/* advlock */
};

/*
 * Trivial lookup routine that always fails.
 */
/* ARGSUSED */
fifo_lookup(vp, ndp, p)
	struct vnode *vp;
	struct nameidata *ndp;
	struct proc *p;
{

	ndp->ni_dvp = vp;
	ndp->ni_vp = NULL;
	return (ENOTDIR);
}

/*
 * Open called to set up a new instance of a fifo or
 * to find an active instance of a fifo.
 */
/* ARGSUSED */
fifo_open(vp, mode, cred, p)
	register struct vnode *vp;
	int mode;
	struct ucred *cred;
	struct proc *p;
{
	register struct fifoinfo *fip;
	struct socket *rso, *wso;
	int error;
	static char openstr[] = "fifo";

	if ((mode & (FREAD|FWRITE)) == (FREAD|FWRITE))
		return (EINVAL);
	if ((fip = vp->v_fifoinfo) == NULL) {
		MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK);
		vp->v_fifoinfo = fip;
		fip->fi_readers = fip->fi_writers = 0;
		if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		fip->fi_readsock = rso;
		if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
			(void)soclose(rso);
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		fip->fi_writesock = wso;
		if (error = unp_connect2(wso, rso)) {
			(void)soclose(wso);
			(void)soclose(rso);
			free(fip, M_VNODE);
			vp->v_fifoinfo = NULL;
			return (error);
		}
		wso->so_state |= SS_CANTRCVMORE;
		rso->so_state |= SS_CANTSENDMORE;
	}
	error = 0;
	if (mode & FREAD) {
		fip->fi_readers++;
		if (fip->fi_readers == 1) {
			fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
			if (fip->fi_writers > 0)
				wakeup((caddr_t)&fip->fi_writers);
		}
		if (mode & O_NONBLOCK)
			return (0);
		while (fip->fi_writers == 0) {
			VOP_UNLOCK(vp);
			error = tsleep((caddr_t)&fip->fi_readers, PSOCK | PCATCH,
			    		openstr, 0);
			VOP_LOCK(vp);
			if (error)
				break;
		}
	} else {
		fip->fi_writers++;
		if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
			error = ENXIO;
		} else {
			if (fip->fi_writers == 1) {
				fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
				if (fip->fi_readers > 0)
					wakeup((caddr_t)&fip->fi_readers);
			}
			while (fip->fi_readers == 0) {
				VOP_UNLOCK(vp);
				error = tsleep((caddr_t)&fip->fi_writers,
				    		PSOCK | PCATCH, openstr, 0);
				VOP_LOCK(vp);
				if (error)
					break;
			}
		}
	}
	if (error)
		fifo_close(vp, mode, cred, p);
	return (error);
}

/*
 * Vnode op for read
 */
/* ARGSUSED */
fifo_read(vp, uio, ioflag, cred)
	struct vnode *vp;
	register struct uio *uio;
	int ioflag;
	struct ucred *cred;
{
	register struct socket *rso = vp->v_fifoinfo->fi_readsock;
	int error, startresid;

#ifdef DIAGNOSTIC
	if (uio->uio_rw != UIO_READ)
		panic("fifo_read mode");
#endif
	if (uio->uio_resid == 0)
		return (0);
	if (ioflag & IO_NDELAY)
		rso->so_state |= SS_NBIO;
	startresid = uio->uio_resid;
	VOP_UNLOCK(vp);
	error = soreceive(rso, (struct mbuf **)0, uio, (int *)0,
		(struct mbuf **)0, (struct mbuf **)0);
	VOP_LOCK(vp);
	/*
	 * Clear EOF indication after first such return.
	 */
	if (uio->uio_resid == startresid)
		rso->so_state &= ~SS_CANTRCVMORE;
	if (ioflag & IO_NDELAY)
		rso->so_state &= ~SS_NBIO;
	return (error);
}

/*
 * Vnode op for write
 */
/* ARGSUSED */
fifo_write(vp, uio, ioflag, cred)
	struct vnode *vp;
	register struct uio *uio;
	int ioflag;
	struct ucred *cred;
{
	struct socket *wso = vp->v_fifoinfo->fi_writesock;
	int error;

#ifdef DIAGNOSTIC
	if (uio->uio_rw != UIO_WRITE)
		panic("fifo_write mode");
#endif
	if (ioflag & IO_NDELAY)
		wso->so_state |= SS_NBIO;
	VOP_UNLOCK(vp);
	error = sosend(wso, (struct mbuf *)0, uio, 0, (struct mbuf *)0, 0);
	VOP_LOCK(vp);
	if (ioflag & IO_NDELAY)
		wso->so_state &= ~SS_NBIO;
	return (error);
}

/*
 * Device ioctl operation.
 */
/* ARGSUSED */
fifo_ioctl(vp, com, data, fflag, cred, p)
	struct vnode *vp;
	int com;
	caddr_t data;
	int fflag;
	struct ucred *cred;
	struct proc *p;
{
	struct file filetmp;
	int error;

	if (com == FIONBIO)
		return (0);
	if (fflag & FREAD)
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	else
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	return (soo_ioctl(&filetmp, com, data, p));
}

/* ARGSUSED */
fifo_select(vp, which, fflag, cred, p)
	struct vnode *vp;
	int which, fflag;
	struct ucred *cred;
	struct proc *p;
{
	struct file filetmp;
	int error;

	if (fflag & FREAD)
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	else
		filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	return (soo_select(&filetmp, which, p));
}

/*
 * This is a noop, simply returning what one has been given.
 */
fifo_bmap(vp, bn, vpp, bnp)
	struct vnode *vp;
	daddr_t bn;
	struct vnode **vpp;
	daddr_t *bnp;
{

	if (vpp != NULL)
		*vpp = vp;
	if (bnp != NULL)
		*bnp = bn;
	return (0);
}

/*
 * At the moment we do not do any locking.
 */
/* ARGSUSED */
fifo_lock(vp)
	struct vnode *vp;
{

	return (0);
}

/* ARGSUSED */
fifo_unlock(vp)
	struct vnode *vp;
{

	return (0);
}

/*
 * Device close routine
 */
/* ARGSUSED */
fifo_close(vp, fflag, cred, p)
	register struct vnode *vp;
	int fflag;
	struct ucred *cred;
	struct proc *p;
{
	register struct fifoinfo *fip = vp->v_fifoinfo;
	int error1, error2;

	if (fflag & FWRITE) {
		fip->fi_writers--;
		if (fip->fi_writers == 0)
			socantrcvmore(fip->fi_readsock);
	} else {
		fip->fi_readers--;
		if (fip->fi_readers == 0)
			socantsendmore(fip->fi_writesock);
	}
	if (vp->v_usecount > 1)
		return (0);
	error1 = soclose(fip->fi_readsock);
	error2 = soclose(fip->fi_writesock);
	FREE(fip, M_VNODE);
	vp->v_fifoinfo = NULL;
	if (error1)
		return (error1);
	return (error2);
}

/*
 * Print out the contents of a fifo vnode.
 */
fifo_print(vp)
	struct vnode *vp;
{

	printf("tag VT_NON");
	fifo_printinfo(vp);
	printf("\n");
}

/*
 * Print out internal contents of a fifo vnode.
 */
fifo_printinfo(vp)
	struct vnode *vp;
{
	register struct fifoinfo *fip = vp->v_fifoinfo;

	printf(", fifo with %d readers and %d writers",
		fip->fi_readers, fip->fi_writers);
}

/*
 * Fifo failed operation
 */
fifo_ebadf()
{

	return (EBADF);
}

/*
 * Fifo advisory byte-level locks.
 */
/* ARGSUSED */
fifo_advlock(vp, id, op, fl, flags)
	struct vnode *vp;
	caddr_t id;
	int op;
	struct flock *fl;
	int flags;
{

	return (EOPNOTSUPP);
}

/*
 * Fifo bad operation
 */
fifo_badop()
{

	panic("fifo_badop called");
	/* NOTREACHED */
}
#endif	/*FIFO*/
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1990 The Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*
	33	* @(#)fifo_vnops.c 7.7 (Berkeley) 4/15/91
	34	*
	35	* PATCHES MAGIC LEVEL PATCH THAT GOT US HERE
	36	* -------------------- ----- ----------------------
	37	* CURRENT PATCH LEVEL: 1 00141
	38	* -------------------- ----- ----------------------
	39	*
	40	* 20 Apr 93 Jay Fenlason 1. fi_{readers\|fi_writers} of fifoinfo init to 0
	41	* 2. fifo_open() was calling tsleep() without
	42	* unlocking the inode of the fifo
	43	*/
	44
cfdfcf49	45	#ifdef FIFO
15637ed4 RG	46	#include "param.h"
	47	#include "time.h"
	48	#include "namei.h"
	49	#include "vnode.h"
	50	#include "socket.h"
	51	#include "socketvar.h"
	52	#include "stat.h"
	53	#include "systm.h"
	54	#include "ioctl.h"
	55	#include "file.h"
	56	#include "fifo.h"
	57	#include "errno.h"
	58	#include "malloc.h"
	59
	60	/*
	61	* This structure is associated with the FIFO vnode and stores
	62	* the state associated with the FIFO.
	63	*/
	64	struct fifoinfo {
	65	struct socket *fi_readsock;
	66	struct socket *fi_writesock;
	67	long fi_readers;
	68	long fi_writers;
	69	};
	70
	71	struct vnodeops fifo_vnodeops = {
	72	fifo_lookup, /* lookup */
	73	fifo_create, /* create */
	74	fifo_mknod, /* mknod */
	75	fifo_open, /* open */
	76	fifo_close, /* close */
	77	fifo_access, /* access */
	78	fifo_getattr, /* getattr */
	79	fifo_setattr, /* setattr */
	80	fifo_read, /* read */
	81	fifo_write, /* write */
	82	fifo_ioctl, /* ioctl */
	83	fifo_select, /* select */
	84	fifo_mmap, /* mmap */
	85	fifo_fsync, /* fsync */
	86	fifo_seek, /* seek */
	87	fifo_remove, /* remove */
	88	fifo_link, /* link */
	89	fifo_rename, /* rename */
	90	fifo_mkdir, /* mkdir */
	91	fifo_rmdir, /* rmdir */
	92	fifo_symlink, /* symlink */
	93	fifo_readdir, /* readdir */
	94	fifo_readlink, /* readlink */
	95	fifo_abortop, /* abortop */
	96	fifo_inactive, /* inactive */
	97	fifo_reclaim, /* reclaim */
	98	fifo_lock, /* lock */
	99	fifo_unlock, /* unlock */
	100	fifo_bmap, /* bmap */
	101	fifo_strategy, /* strategy */
	102	fifo_print, /* print */
	103	fifo_islocked, /* islocked */
	104	fifo_advlock, /* advlock */
	105	};
	106
	107	/*
	108	* Trivial lookup routine that always fails.
	109	*/
110	/* ARGSUSED */
111	fifo_lookup(vp, ndp, p)
112	struct vnode *vp;
113	struct nameidata *ndp;
114	struct proc *p;
115	{
116
117	ndp->ni_dvp = vp;
118	ndp->ni_vp = NULL;
119	return (ENOTDIR);
120	}
121
122	/*
123	* Open called to set up a new instance of a fifo or
124	* to find an active instance of a fifo.
125	*/
126	/* ARGSUSED */
127	fifo_open(vp, mode, cred, p)
128	register struct vnode *vp;
129	int mode;
130	struct ucred *cred;
131	struct proc *p;
132	{
133	register struct fifoinfo *fip;
134	struct socket rso, wso;
135	int error;
136	static char openstr[] = "fifo";
137
138	if ((mode & (FREAD\|FWRITE)) == (FREAD\|FWRITE))
139	return (EINVAL);
140	if ((fip = vp->v_fifoinfo) == NULL) {
141	MALLOC(fip, struct fifoinfo , sizeof(fip), M_VNODE, M_WAITOK);
142	vp->v_fifoinfo = fip;
143	fip->fi_readers = fip->fi_writers = 0;
144	if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) {
145	free(fip, M_VNODE);
146	vp->v_fifoinfo = NULL;
147	return (error);
148	}
149	fip->fi_readsock = rso;
150	if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) {
151	(void)soclose(rso);
152	free(fip, M_VNODE);
153	vp->v_fifoinfo = NULL;
154	return (error);
155	}
156	fip->fi_writesock = wso;
157	if (error = unp_connect2(wso, rso)) {
158	(void)soclose(wso);
159	(void)soclose(rso);
160	free(fip, M_VNODE);
161	vp->v_fifoinfo = NULL;
162	return (error);
163	}
164	wso->so_state \|= SS_CANTRCVMORE;
165	rso->so_state \|= SS_CANTSENDMORE;
166	}
167	error = 0;
168	if (mode & FREAD) {
169	fip->fi_readers++;
170	if (fip->fi_readers == 1) {
171	fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
172	if (fip->fi_writers > 0)
173	wakeup((caddr_t)&fip->fi_writers);
174	}
175	if (mode & O_NONBLOCK)
176	return (0);
177	while (fip->fi_writers == 0) {
178	VOP_UNLOCK(vp);
179	error = tsleep((caddr_t)&fip->fi_readers, PSOCK \| PCATCH,
180	openstr, 0);
181	VOP_LOCK(vp);
182	if (error)
183	break;
184	}
185	} else {
186	fip->fi_writers++;
187	if (fip->fi_readers == 0 && (mode & O_NONBLOCK)) {
188	error = ENXIO;
189	} else {
190	if (fip->fi_writers == 1) {
191	fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
192	if (fip->fi_readers > 0)
193	wakeup((caddr_t)&fip->fi_readers);
194	}
195	while (fip->fi_readers == 0) {
196	VOP_UNLOCK(vp);
197	error = tsleep((caddr_t)&fip->fi_writers,
198	PSOCK \| PCATCH, openstr, 0);
199	VOP_LOCK(vp);
200	if (error)
201	break;
202	}
203	}
204	}
205	if (error)
206	fifo_close(vp, mode, cred, p);
207	return (error);
208	}
209
210	/*
211	* Vnode op for read
212	*/
213	/* ARGSUSED */
214	fifo_read(vp, uio, ioflag, cred)
215	struct vnode *vp;
216	register struct uio *uio;
217	int ioflag;
218	struct ucred *cred;
219	{
220	register struct socket *rso = vp->v_fifoinfo->fi_readsock;
221	int error, startresid;
222
223	#ifdef DIAGNOSTIC
224	if (uio->uio_rw != UIO_READ)
225	panic("fifo_read mode");
226	#endif
227	if (uio->uio_resid == 0)
228	return (0);
229	if (ioflag & IO_NDELAY)
230	rso->so_state \|= SS_NBIO;
231	startresid = uio->uio_resid;
232	VOP_UNLOCK(vp);
233	error = soreceive(rso, (struct mbuf *)0, uio, (int )0,
234	(struct mbuf )0, (struct mbuf )0);
235	VOP_LOCK(vp);
236	/*
237	* Clear EOF indication after first such return.
238	*/
239	if (uio->uio_resid == startresid)
240	rso->so_state &= ~SS_CANTRCVMORE;
241	if (ioflag & IO_NDELAY)
242	rso->so_state &= ~SS_NBIO;
243	return (error);
244	}
245
246	/*
247	* Vnode op for write
248	*/
249	/* ARGSUSED */
250	fifo_write(vp, uio, ioflag, cred)
251	struct vnode *vp;
252	register struct uio *uio;
253	int ioflag;
254	struct ucred *cred;
255	{
256	struct socket *wso = vp->v_fifoinfo->fi_writesock;
257	int error;
258
259	#ifdef DIAGNOSTIC
260	if (uio->uio_rw != UIO_WRITE)
261	panic("fifo_write mode");
262	#endif
263	if (ioflag & IO_NDELAY)
264	wso->so_state \|= SS_NBIO;
265	VOP_UNLOCK(vp);
8604ac85	266	error = sosend(wso, (struct mbuf )0, uio, 0, (struct mbuf )0, 0);
15637ed4 RG	267	VOP_LOCK(vp);
	268	if (ioflag & IO_NDELAY)
	269	wso->so_state &= ~SS_NBIO;
	270	return (error);
	271	}
	272
	273	/*
	274	* Device ioctl operation.
	275	*/
	276	/* ARGSUSED */
	277	fifo_ioctl(vp, com, data, fflag, cred, p)
	278	struct vnode *vp;
	279	int com;
	280	caddr_t data;
	281	int fflag;
	282	struct ucred *cred;
	283	struct proc *p;
	284	{
	285	struct file filetmp;
	286	int error;
	287
	288	if (com == FIONBIO)
	289	return (0);
	290	if (fflag & FREAD)
	291	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	292	else
	293	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	294	return (soo_ioctl(&filetmp, com, data, p));
	295	}
	296
	297	/* ARGSUSED */
	298	fifo_select(vp, which, fflag, cred, p)
	299	struct vnode *vp;
	300	int which, fflag;
	301	struct ucred *cred;
	302	struct proc *p;
	303	{
	304	struct file filetmp;
	305	int error;
	306
	307	if (fflag & FREAD)
	308	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_readsock;
	309	else
	310	filetmp.f_data = (caddr_t)vp->v_fifoinfo->fi_writesock;
	311	return (soo_select(&filetmp, which, p));
	312	}
	313
	314	/*
	315	* This is a noop, simply returning what one has been given.
	316	*/
	317	fifo_bmap(vp, bn, vpp, bnp)
	318	struct vnode *vp;
	319	daddr_t bn;
	320	struct vnode **vpp;
	321	daddr_t *bnp;
	322	{
	323
	324	if (vpp != NULL)
	325	*vpp = vp;
	326	if (bnp != NULL)
	327	*bnp = bn;
	328	return (0);
	329	}
	330
331	/*
332	* At the moment we do not do any locking.
333	*/
334	/* ARGSUSED */
335	fifo_lock(vp)
336	struct vnode *vp;
337	{
338
339	return (0);
340	}
341
342	/* ARGSUSED */
343	fifo_unlock(vp)
344	struct vnode *vp;
345	{
346
347	return (0);
348	}
349
350	/*
351	* Device close routine
352	*/
353	/* ARGSUSED */
354	fifo_close(vp, fflag, cred, p)
355	register struct vnode *vp;
356	int fflag;
357	struct ucred *cred;
358	struct proc *p;
359	{
360	register struct fifoinfo *fip = vp->v_fifoinfo;
361	int error1, error2;
362
363	if (fflag & FWRITE) {
364	fip->fi_writers--;
365	if (fip->fi_writers == 0)
366	socantrcvmore(fip->fi_readsock);
367	} else {
368	fip->fi_readers--;
369	if (fip->fi_readers == 0)
370	socantsendmore(fip->fi_writesock);
371	}
372	if (vp->v_usecount > 1)
373	return (0);
374	error1 = soclose(fip->fi_readsock);
375	error2 = soclose(fip->fi_writesock);
376	FREE(fip, M_VNODE);
377	vp->v_fifoinfo = NULL;
378	if (error1)
379	return (error1);
380	return (error2);
381	}
382
383	/*
384	* Print out the contents of a fifo vnode.
385	*/
386	fifo_print(vp)
387	struct vnode *vp;
388	{
389
390	printf("tag VT_NON");
391	fifo_printinfo(vp);
392	printf("\n");
393	}
394
395	/*
396	* Print out internal contents of a fifo vnode.
397	*/
398	fifo_printinfo(vp)
399	struct vnode *vp;
400	{
401	register struct fifoinfo *fip = vp->v_fifoinfo;
402
403	printf(", fifo with %d readers and %d writers",
404	fip->fi_readers, fip->fi_writers);
405	}
406
407	/*
408	* Fifo failed operation
409	*/
410	fifo_ebadf()
411	{
412
413	return (EBADF);
414	}
415
416	/*
417	* Fifo advisory byte-level locks.
418	*/
419	/* ARGSUSED */
420	fifo_advlock(vp, id, op, fl, flags)
421	struct vnode *vp;
422	caddr_t id;
423	int op;
424	struct flock *fl;
425	int flags;
426	{
427
428	return (EOPNOTSUPP);
429	}
430
431	/*
432	* Fifo bad operation
433	*/
434	fifo_badop()
435	{
436
437	panic("fifo_badop called");
438	/* NOTREACHED */
439	}
cfdfcf49	440	#endif /FIFO/