Source to bsd/kern/sys_generic.c
/*
* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
*
* @[email protected]
*
* "Portions Copyright (c) 1999 Apple Computer, Inc. All Rights
* Reserved. This file contains Original Code and/or Modifications of
* Original Code as defined in and that are subject to the Apple Public
* Source License Version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. Please obtain a copy of the
* License at http://www.apple.com/publicsource and read it before using
* this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
* License for the specific language governing rights and limitations
* under the License."
*
* @[email protected]
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
*
* @(#)sys_generic.c 8.9 (Berkeley) 2/14/95
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <sys/proc.h>
#include <sys/socketvar.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/malloc.h>
#if KTRACE
#include <sys/ktrace.h>
#endif
#include <sys/mount.h>
#include <sys/protosw.h>
#include <sys/ev.h>
#include <sys/user.h>
#include <kern/kdebug.h>
/*
* Read system call.
*/
struct read_args {
int fd;
char *cbuf;
u_int nbyte;
};
/* ARGSUSED */
read(p, uap, retval)
struct proc *p;
register struct read_args *uap;
register_t *retval;
{
struct uio auio;
struct iovec aiov;
aiov.iov_base = (caddr_t)uap->cbuf;
aiov.iov_len = uap->nbyte;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_READ;
return (rwuio(p, uap->fd, &auio, UIO_READ, retval));
}
struct readv_args {
int fd;
struct iovec *iovp;
u_int iovcnt;
};
readv(p, uap, retval)
struct proc *p;
register struct readv_args *uap;
int *retval;
{
struct uio auio;
register struct iovec *iov;
int error;
struct iovec aiov[UIO_SMALLIOV];
if (uap->iovcnt > UIO_SMALLIOV) {
if (uap->iovcnt > UIO_MAXIOV)
return (EINVAL);
if ((iov = (struct iovec *)
kalloc(sizeof(struct iovec) * (uap->iovcnt))) == 0)
return (ENOMEM);
} else
iov = aiov;
auio.uio_iov = iov;
auio.uio_iovcnt = uap->iovcnt;
auio.uio_rw = UIO_READ;
error = copyin((caddr_t)uap->iovp, (caddr_t)iov,
uap->iovcnt * sizeof (struct iovec));
if (!error)
error = rwuio(p, uap->fd, &auio, UIO_READ, retval);
if (uap->iovcnt > UIO_SMALLIOV)
kfree(iov, sizeof(struct iovec)*uap->iovcnt);
return (error);
}
/*
* Write system call
*/
struct write_args {
int fd;
char *cbuf;
u_int nbyte;
};
write(p, uap, retval)
struct proc *p;
register struct write_args *uap;
int *retval;
{
struct uio auio;
struct iovec aiov;
aiov.iov_base = uap->cbuf;
aiov.iov_len = uap->nbyte;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_rw = UIO_WRITE;
return (rwuio(p, uap->fd, &auio, UIO_WRITE, retval));
}
struct writev_args {
int fd;
struct iovec *iovp;
u_int iovcnt;
};
writev(p, uap, retval)
struct proc *p;
register struct writev_args *uap;
int *retval;
{
struct uio auio;
register struct iovec *iov;
int error;
struct iovec aiov[UIO_SMALLIOV];
if (uap->iovcnt > UIO_SMALLIOV) {
if (uap->iovcnt > UIO_MAXIOV)
return (EINVAL);
if ((iov = (struct iovec *)
kalloc(sizeof(struct iovec) * (uap->iovcnt))) == 0)
return (ENOMEM);
} else
iov = aiov;
auio.uio_iov = iov;
auio.uio_iovcnt = uap->iovcnt;
auio.uio_rw = UIO_WRITE;
error = copyin((caddr_t)uap->iovp, (caddr_t)iov,
uap->iovcnt * sizeof (struct iovec));
if (!error)
error = rwuio(p, uap->fd, &auio, UIO_WRITE, retval);
if (uap->iovcnt > UIO_SMALLIOV)
kfree(iov, sizeof(struct iovec)*uap->iovcnt);
return (error);
}
rwuio(p, fdes, uio, rw, retval)
struct proc *p;
int fdes;
register struct uio *uio;
enum uio_rw rw;
int *retval;
{
register struct file *fp;
register struct iovec *iov;
int i, count, flag, error;
if (error = fdgetf(p, fdes, &fp))
return (error);
if ((fp->f_flag&(rw==UIO_READ ? FREAD : FWRITE)) == 0) {
return(EBADF);
}
uio->uio_resid = 0;
uio->uio_segflg = UIO_USERSPACE;
uio->uio_procp = p;
iov = uio->uio_iov;
for (i = 0; i < uio->uio_iovcnt; i++) {
if (iov->iov_len < 0) {
return(EINVAL);
}
uio->uio_resid += iov->iov_len;
if (uio->uio_resid < 0) {
return(EINVAL);
}
iov++;
}
count = uio->uio_resid;
if (rw == UIO_READ) {
if (error = (*fp->f_ops->fo_read)(fp, uio, fp->f_cred))
if (uio->uio_resid != count && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
} else {
if (error = (*fp->f_ops->fo_write)(fp, uio, fp->f_cred)) {
if (uio->uio_resid != count && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
if (error == EPIPE)
psignal(p, SIGPIPE);
}
}
*retval = count - uio->uio_resid;
return(error);
}
/*
* Ioctl system call
*/
struct ioctl_args {
int fd;
u_long com;
caddr_t data;
};
/* ARGSUSED */
ioctl(p, uap, retval)
struct proc *p;
register struct ioctl_args *uap;
register_t *retval;
{
register struct file *fp;
register u_long com;
register int error;
register u_int size;
caddr_t data, memp;
int tmp;
#define STK_PARAMS 128
char stkbuf[STK_PARAMS];
if (error = fdgetf(p, uap->fd, &fp))
return (error);
if ((fp->f_flag & (FREAD | FWRITE)) == 0)
return (EBADF);
/*### LD 6/11/97 Hack Alert: this is to get AppleTalk to work
* while implementing an ATioctl system call
*/
#if NETAT
{
extern int appletalk_inited;
if (appletalk_inited && ((uap->com & 0x0000FFFF) == 0xff99)) {
#ifdef APPLETALK_DEBUG
kprintf("ioctl: special AppleTalk \n");
#endif
error = (*fp->f_ops->fo_ioctl)(fp, uap->com, uap->data, p);
return(error);
}
}
#endif /* NETAT */
switch (com = uap->com) {
case FIONCLEX:
*fdflags(p, uap->fd) &= ~UF_EXCLOSE;
return (0);
case FIOCLEX:
*fdflags(p, uap->fd) |= UF_EXCLOSE;
return (0);
}
/*
* Interpret high order word to find amount of data to be
* copied to/from the user's address space.
*/
size = IOCPARM_LEN(com);
if (size > IOCPARM_MAX)
return (ENOTTY);
memp = NULL;
if (size > sizeof (stkbuf)) {
if ((memp = (caddr_t)kalloc(size)) == 0)
return(ENOMEM);
data = memp;
} else
data = stkbuf;
if (com&IOC_IN) {
if (size) {
error = copyin(uap->data, data, (u_int)size);
if (error) {
if (memp)
kfree(memp, size);
return (error);
}
} else
*(caddr_t *)data = uap->data;
} else if ((com&IOC_OUT) && size)
/*
* Zero the buffer so the user always
* gets back something deterministic.
*/
bzero(data, size);
else if (com&IOC_VOID)
*(caddr_t *)data = uap->data;
switch (com) {
case FIONBIO:
if (tmp = *(int *)data)
fp->f_flag |= FNONBLOCK;
else
fp->f_flag &= ~FNONBLOCK;
error = (*fp->f_ops->fo_ioctl)(fp, FIONBIO, (caddr_t)&tmp, p);
break;
case FIOASYNC:
if (tmp = *(int *)data)
fp->f_flag |= FASYNC;
else
fp->f_flag &= ~FASYNC;
error = (*fp->f_ops->fo_ioctl)(fp, FIOASYNC, (caddr_t)&tmp, p);
break;
case FIOSETOWN:
tmp = *(int *)data;
if (fp->f_type == DTYPE_SOCKET) {
((struct socket *)fp->f_data)->so_pgid = tmp;
error = 0;
break;
}
if (tmp <= 0) {
tmp = -tmp;
} else {
struct proc *p1 = pfind(tmp);
if (p1 == 0) {
error = ESRCH;
break;
}
tmp = p1->p_pgrp->pg_id;
}
error = (*fp->f_ops->fo_ioctl)
(fp, (int)TIOCSPGRP, (caddr_t)&tmp, p);
break;
case FIOGETOWN:
if (fp->f_type == DTYPE_SOCKET) {
error = 0;
*(int *)data = ((struct socket *)fp->f_data)->so_pgid;
break;
}
error = (*fp->f_ops->fo_ioctl)(fp, TIOCGPGRP, data, p);
*(int *)data = -*(int *)data;
break;
default:
error = (*fp->f_ops->fo_ioctl)(fp, com, data, p);
/*
* Copy any data to user, size was
* already set and checked above.
*/
if (error == 0 && (com&IOC_OUT) && size)
error = copyout(data, uap->data, (u_int)size);
break;
}
if (memp)
kfree(memp, size);
return (error);
}
int selwait, nselcoll;
/*
* Select system call.
*/
struct select_args {
u_int nd;
fd_set *in;
fd_set *ou;
fd_set *ex;
struct timeval *tv;
};
select(p, uap, retval)
register struct proc *p;
register struct select_args *uap;
register_t *retval;
{
fd_set ibits[3], obits[3];
struct timeval atv;
int s, ncoll, error = 0, timo;
u_int ni;
struct thread *th;
struct uthread *uth;
th = current_thread();
uth = th->_uthread;
bzero((caddr_t)ibits, sizeof(ibits));
bzero((caddr_t)obits, sizeof(obits));
if (uap->nd > FD_SETSIZE)
return (EINVAL);
if (uap->nd > p->p_fd->fd_nfiles) {
/* forgiving; slightly wrong */
uap->nd = p->p_fd->fd_nfiles;
}
ni = howmany(uap->nd, NFDBITS) * sizeof(fd_mask);
#define getbits(name, x) \
if (uap->name && (error = copyin((caddr_t)uap->name, \
(caddr_t)&ibits[x], ni))) \
goto done;
getbits(in, 0);
getbits(ou, 1);
getbits(ex, 2);
#undef getbits
if (uap->tv) {
error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
sizeof (atv));
if (error)
goto done;
if (itimerfix(&atv)) {
error = EINVAL;
goto done;
}
s = splhigh();
timeradd(&atv, &time, &atv);
timo = hzto(&atv);
splx(s);
} else
timo = 0;
retry:
ncoll = nselcoll;
p->p_flag |= P_SELECT;
error = selscan(p, ibits, obits, uap->nd, retval);
if (error || *retval)
goto done;
s = splhigh();
/* this should be timercmp(&time, &atv, >=) */
if (uap->tv && (time.tv_sec > atv.tv_sec ||
time.tv_sec == atv.tv_sec && time.tv_usec >= atv.tv_usec)) {
splx(s);
goto done;
}
/*
* To effect a poll, the timeout argument should be
* non-nil, pointing to a zero-valued timeval structure.
*/
if (uap->tv && (timo == 0)) {
splx(s);
goto done;
}
if ((p->p_flag & P_SELECT) == 0 || nselcoll != ncoll) {
splx(s);
goto retry;
}
p->p_flag &= ~P_SELECT;
error = tsleep((caddr_t)&selwait, PSOCK | PCATCH, "select", timo);
splx(s);
if (error == 0)
goto retry;
done:
p->p_flag &= ~P_SELECT;
/* select is not restarted after signals... */
if (error == ERESTART)
error = EINTR;
if (error == EWOULDBLOCK)
error = 0;
#define putbits(name, x) \
if (uap->name && (error2 = copyout((caddr_t)&obits[x], \
(caddr_t)uap->name, ni))) \
error = error2;
if (error == 0) {
int error2;
putbits(in, 0);
putbits(ou, 1);
putbits(ex, 2);
#undef putbits
}
return (error);
}
selscan(p, ibits, obits, nfd, retval)
struct proc *p;
fd_set *ibits, *obits;
int nfd;
register_t *retval;
{
register struct filedesc *fdp = p->p_fd;
register int msk, i, j, fd;
register fd_mask bits;
struct file *fp;
int n = 0;
static int flag[3] = { FREAD, FWRITE, 0 };
for (msk = 0; msk < 3; msk++) {
for (i = 0; i < nfd; i += NFDBITS) {
bits = ibits[msk].fds_bits[i/NFDBITS];
while ((j = ffs(bits)) && (fd = i + --j) < nfd) {
bits &= ~(1 << j);
fp = fdp->fd_ofiles[fd];
if (fp == NULL || (fdp->fd_ofileflags[fd] &
UF_RESERVED))
return (EBADF);
if ((*fp->f_ops->fo_select)(fp, flag[msk], p)) {
FD_SET(fd, &obits[msk]);
n++;
}
}
}
}
*retval = n;
return (0);
}
/*ARGSUSED*/
seltrue(dev, flag, p)
dev_t dev;
int flag;
struct proc *p;
{
return (1);
}
/*
* Record a select request.
*/
void
selrecord(selector, sip)
struct proc *selector;
struct selinfo *sip;
{
int oldpri = splhigh();
thread_t my_thread = current_thread();
thread_t selthread;
selthread = sip->si_thread;
if (selthread == my_thread) {
splx(oldpri);
return;
}
if (selthread && selthread->active &&
selthread->wait_event == (caddr_t)&selwait) {
sip->si_flags |= SI_COLL;
splx(oldpri);
}
else {
sip->si_thread = my_thread;
splx(oldpri);
thread_deallocate(selthread);
thread_reference(sip->si_thread);
}
return;
}
void
selwakeup(sip)
register struct selinfo *sip;
{
register thread_t the_thread = (thread_t)sip->si_thread;
int oldpri;
if (the_thread == 0)
return;
if (sip->si_flags & SI_COLL) {
nselcoll++;
sip->si_flags &= ~SI_COLL;
wakeup((caddr_t)&selwait);
}
oldpri = splhigh();
if (the_thread->active) {
/* protect p_flag minimally at splsched() */
if (the_thread->wait_event == &selwait)
clear_wait(the_thread, THREAD_AWAKENED, TRUE);
if (the_thread->task->proc)
the_thread->task->proc->p_flag &= ~P_SELECT;
}
thread_deallocate_interrupt(the_thread);
sip->si_thread = 0;
splx(oldpri);
}
void selthreadclear(sip)
register struct selinfo *sip;
{
if (sip->si_thread)
thread_deallocate_interrupt(sip->si_thread);
}
/*
* called upon socket close. deque and free all events for
* the socket
*/
evsofree(struct socket *sp)
{
struct eventqelt *eqp, *next;
if (sp == NULL) return;
for (eqp = sp->so_evlist.tqh_first; eqp != NULL; eqp = next) {
next = eqp->ee_slist.tqe_next;
evprocdeque(eqp->ee_proc, eqp); // remove from proc q if there
TAILQ_REMOVE(&sp->so_evlist, eqp, ee_slist); // remove from socket q
FREE(eqp, M_TEMP);
}
}
#define DBG_EVENT 0x10
#define DBG_POST 0x10
#define DBG_WATCH 0x11
#define DBG_WAIT 0x12
#define DBG_MOD 0x13
#define DBG_EWAKEUP 0x14
#define DBG_MISC_POST MISCDBG_CODE(DBG_EVENT,DBG_POST)
#define DBG_MISC_WATCH MISCDBG_CODE(DBG_EVENT,DBG_WATCH)
#define DBG_MISC_WAIT MISCDBG_CODE(DBG_EVENT,DBG_WAIT)
#define DBG_MISC_MOD MISCDBG_CODE(DBG_EVENT,DBG_MOD)
#define DBG_MISC_EWAKEUP MISCDBG_CODE(DBG_EVENT,DBG_EWAKEUP)
/*
* enque this event if it's not already queued. wakeup
the proc if we do queue this event to it.
*/
evprocenque(struct eventqelt *eqp)
{
struct proc *p;
assert(eqp);
if (eqp->ee_flags & EV_QUEUED) {
return;
}
eqp->ee_flags |= EV_QUEUED;
eqp->ee_eventmask = 0; // disarm
p = eqp->ee_proc;
TAILQ_INSERT_TAIL(&p->p_evlist, eqp, ee_plist);
KERNEL_DEBUG(DBG_MISC_EWAKEUP,0,0,0,eqp,0);
wakeup(&p->p_evlist);
}
/*
* given either a sockbuf or a socket run down the
* event list and queue ready events found
*/
postevent(struct socket *sp, struct sockbuf *sb, int event)
{
int mask;
struct eventqelt *evq;
if (sb) sp = sb->sb_so;
if (!sp || sp->so_evlist.tqh_first == NULL) return;
KERNEL_DEBUG(DBG_MISC_POST|DBG_FUNC_START, 0,0,0,0,0);
for (evq = sp->so_evlist.tqh_first;
evq != NULL; evq = evq->ee_slist.tqe_next) {
mask = 0;
/* ready for reading:
- byte cnt >= receive low water mark
- read-half of conn closed
- conn pending for listening sock
- socket error pending
ready for writing
- byte cnt avail >= send low water mark
- write half of conn closed
- socket error pending
- non-blocking conn completed successfully
exception pending
- out of band data
- sock at out of band mark
*/
switch (event & EV_DMASK) {
case EV_RWBYTES:
case EV_OOB:
if (event & EV_OOB) {
if ((evq->ee_eventmask & EV_EX)) {
if (sp->so_oobmark || ((sp->so_state & SS_RCVATMARK))) {
mask |= EV_EX|EV_OOB;
}
}
}
if (event & EV_RWBYTES) {
if ((evq->ee_eventmask & EV_RE) && soreadable(sp)) {
mask |= EV_RE;
evq->ee_req.er_rcnt = sp->so_rcv.sb_cc;
}
if ((evq->ee_eventmask & EV_WR) && sowriteable(sp)) {
mask |= EV_WR;
evq->ee_req.er_wcnt = sbspace(&sp->so_snd);
}
}
break;
case EV_RCONN:
if ((evq->ee_eventmask & EV_RE)) {
evq->ee_req.er_rcnt = sp->so_qlen + 1; // incl this one
mask |= EV_RE|EV_RCONN;
}
break;
case EV_WCONN:
if ((evq->ee_eventmask & EV_WR)) {
mask |= EV_WR|EV_WCONN;
}
break;
case EV_RCLOSED:
if ((evq->ee_eventmask & EV_RE)) {
mask |= EV_RE|EV_RCLOSED;
break;
}
case EV_WCLOSED:
if ((evq->ee_eventmask & EV_WR)) {
mask |= EV_WR|EV_WCLOSED;
break;
}
case EV_FIN:
if (evq->ee_eventmask & EV_EX) {
mask |= EV_EX|EV_FIN;
break;
}
case EV_RESET:
if (evq->ee_eventmask & EV_EX) {
mask |= EV_EX|EV_RESET;
break;
}
default:
return;
} /* switch */
if (mask) {
evq->ee_req.er_eventbits |= mask;
evprocenque(evq);
}
}
KERNEL_DEBUG(DBG_MISC_POST|DBG_FUNC_END, 0,0,0,0,0);
}
/*
* remove and return the first event (eqp=NULL) or a specific
* event, or return NULL if no events found
*/
struct eventqelt *
evprocdeque(struct proc *p, struct eventqelt *eqp)
{
if (eqp && ((eqp->ee_flags & EV_QUEUED) == NULL))
return(NULL);
if (p->p_evlist.tqh_first == NULL)
return(NULL);
if (eqp == NULL) { // remove first
eqp = p->p_evlist.tqh_first;
}
TAILQ_REMOVE(&p->p_evlist, eqp, ee_plist);
eqp->ee_flags &= ~EV_QUEUED;
return(eqp);
}
struct evwatch_args {
struct eventreq *u_req;
int u_eventmask;
};
/*
* watchevent system call. user passes us an event to watch
* for. we malloc an event object, initialize it, and queue
* it to the open socket. when the event occurs, postevent()
* will enque it back to our proc where we can retrieve it
* via waitevent().
*
* should this prevent duplicate events on same socket?
*/
int
watchevent(p, uap, retval)
struct proc *p;
struct evwatch_args *uap;
register_t *retval;
{
struct eventqelt *eqp = (struct eventqelt *)0;
struct eventqelt *np;
struct eventreq *erp;
struct file *fp;
struct socket *sp;
int error;
// get a qelt and fill with users req
MALLOC(eqp, struct eventqelt *, sizeof(struct eventqelt), M_TEMP, M_WAITOK);
if (!eqp) panic("can't MALLOC eqp");
erp = &eqp->ee_req;
// get users request pkt
if (error = copyin((caddr_t)uap->u_req, (caddr_t)erp,
sizeof(struct eventreq))) {
FREE(eqp, M_TEMP);
KERNEL_DEBUG(DBG_MISC_WATCH|DBG_FUNC_END, 0,0,0,0,0);
return(error);
}
KERNEL_DEBUG(DBG_MISC_WATCH|DBG_FUNC_START, 0,
erp->er_handle,uap->u_eventmask,eqp,0);
// validate, freeing qelt if errors
error = 0;
if (erp->er_type != EV_FD) {
error = EINVAL;
} else if (erp->er_handle < 0) {
error = EBADF;
} else if (erp->er_handle > p->p_fd->fd_nfiles) {
error = EBADF;
} else if ((fp = *fdfile(p, erp->er_handle)) == NULL) {
error = EBADF;
} else if (fp->f_type != DTYPE_SOCKET) {
error = EINVAL;
}
if (error) {
FREE(eqp,M_TEMP);
KERNEL_DEBUG(DBG_MISC_WATCH|DBG_FUNC_END, 0,0,0,0,0);
return(error);
}
erp->er_rcnt = erp->er_wcnt = erp->er_eventbits = 0;
eqp->ee_proc = p;
eqp->ee_eventmask = uap->u_eventmask & EV_MASK;
eqp->ee_flags = 0;
sp = (struct socket *)fp->f_data;
assert(sp != NULL);
// only allow one watch per file per proc
for (np = sp->so_evlist.tqh_first; np != NULL; np = np->ee_slist.tqe_next) {
if (np->ee_proc == p) {
FREE(eqp,M_TEMP);
KERNEL_DEBUG(DBG_MISC_WATCH|DBG_FUNC_END, 0,0,0,0,0);
return(EINVAL);
}
}
TAILQ_INSERT_TAIL(&sp->so_evlist, eqp, ee_slist);
postevent(sp, 0, EV_RWBYTES); // catch existing events
KERNEL_DEBUG(DBG_MISC_WATCH|DBG_FUNC_END, 0,0,0,0,0);
return(0);
}
struct evwait_args {
struct eventreq *u_req;
struct timeval *tv;
};
/*
* waitevent system call.
* grabs the next waiting event for this proc and returns
* it. if no events, user can request to sleep with timeout
* or poll mode (tv=NULL);
*/
int
waitevent(p, uap, retval)
struct proc *p;
struct evwait_args *uap;
register_t *retval;
{
int error = 0;
struct eventqelt *eqp;
int timo;
struct timeval atv;
int s;
if (uap->tv) {
error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
sizeof (atv));
if (error)
return(error);
if (itimerfix(&atv)) {
error = EINVAL;
return(error);
}
s = splhigh();
timeradd(&atv, &time, &atv);
timo = hzto(&atv);
splx(s);
} else
timo = 0;
KERNEL_DEBUG(DBG_MISC_WAIT|DBG_FUNC_START, 0,0,0,0,0);
retry:
s = splhigh();
if ((eqp = evprocdeque(p,NULL)) != NULL) {
splx(s);
error = copyout((caddr_t)&eqp->ee_req, (caddr_t)uap->u_req,
sizeof(struct eventreq));
KERNEL_DEBUG(DBG_MISC_WAIT|DBG_FUNC_END, 0,
eqp->ee_req.er_handle,eqp->ee_req.er_eventbits,eqp,0);
return(error);
} else {
if (uap->tv && (timo == 0)) {
splx(s);
*retval = 1; // poll failed
return(error);
}
KERNEL_DEBUG(DBG_MISC_WAIT, 1,0,0,0,0);
error = tsleep(&p->p_evlist, PSOCK | PCATCH, "waitevent", timo);
KERNEL_DEBUG(DBG_MISC_WAIT, 0,0,2,p->p_evlist.tqh_first,0);
splx(s);
if (error == 0)
goto retry;
if (error == ERESTART)
error = EINTR;
if (error == EWOULDBLOCK) {
*retval = 1;
error = 0;
}
}
KERNEL_DEBUG(DBG_MISC_WAIT|DBG_FUNC_END, 0,0,0,0,0);
return(error);
}
struct modwatch_args {
struct eventreq *u_req;
int u_eventmask;
};
/*
* modwatch system call. user passes in event to modify.
* if we find it we reset the event bits and que/deque event
* it needed.
*/
int
modwatch(p, uap, retval)
struct proc *p;
struct modwatch_args *uap;
register_t *retval;
{
struct eventreq er;
struct eventreq *erp = &er;
struct eventqelt *evq;
int error;
struct file *fp;
struct socket *sp;
int flag;
// get users request pkt
if (error = copyin((caddr_t)uap->u_req, (caddr_t)erp,
sizeof(struct eventreq))) return(error);
if (erp->er_type != EV_FD) return(EINVAL);
if (erp->er_handle < 0) return(EBADF);
if (erp->er_handle > p->p_fd->fd_nfiles) return(EBADF);
if ((fp = *fdfile(p, erp->er_handle)) == NULL)
return(EBADF);
if (fp->f_type != DTYPE_SOCKET) return(EINVAL); // for now must be sock
sp = (struct socket *)fp->f_data;
assert(sp != NULL);
// locate event if possible
for (evq = sp->so_evlist.tqh_first;
evq != NULL; evq = evq->ee_slist.tqe_next) {
if (evq->ee_proc == p) break;
}
if (evq == NULL) {
return(EINVAL);
}
if (uap->u_eventmask == EV_RM) {
evprocdeque(p, evq);
TAILQ_REMOVE(&sp->so_evlist, evq, ee_slist);
FREE(evq, M_TEMP);
return(0);
}
switch (uap->u_eventmask & EV_MASK) {
case 0:
flag = 0;
break;
case EV_RE:
case EV_WR:
case EV_RE|EV_WR:
flag = EV_RWBYTES;
break;
case EV_EX:
flag = EV_OOB;
break;
case EV_EX|EV_RE:
case EV_EX|EV_WR:
case EV_EX|EV_RE|EV_WR:
flag = EV_OOB|EV_RWBYTES;
break;
default:
return(EINVAL);
}
evq->ee_eventmask = uap->u_eventmask & EV_MASK;
evprocdeque(p, evq);
evq->ee_req.er_eventbits = 0;
postevent(sp, 0, flag);
return(0);
}