NetBSD/lib/libevent/poll.c

246 lines
5.7 KiB
C

/* $NetBSD: poll.c,v 1.6 2005/04/17 07:20:00 provos Exp $ */
/* $OpenBSD: poll.c,v 1.2 2002/06/25 15:50:15 mickey Exp $ */
/*
* Copyright 2000-2003 Niels Provos <provos@citi.umich.edu>
* 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 Niels Provos.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <sys/_time.h>
#endif
#include <sys/queue.h>
#include <sys/tree.h>
#include <poll.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include "event.h"
#include "event-internal.h"
#include "evsignal.h"
#include "log.h"
extern volatile sig_atomic_t evsignal_caught;
struct pollop {
int event_count; /* Highest number alloc */
struct pollfd *event_set;
struct event **event_back;
sigset_t evsigmask;
};
void *poll_init (void);
int poll_add (void *, struct event *);
int poll_del (void *, struct event *);
int poll_recalc (struct event_base *, void *, int);
int poll_dispatch (struct event_base *, void *, struct timeval *);
struct eventop pollops = {
"poll",
poll_init,
poll_add,
poll_del,
poll_recalc,
poll_dispatch
};
void *
poll_init(void)
{
struct pollop *pollop;
/* Disable kqueue when this environment variable is set */
if (getenv("EVENT_NOPOLL"))
return (NULL);
if (!(pollop = calloc(1, sizeof(struct pollop))))
return (NULL);
evsignal_init(&pollop->evsigmask);
return (pollop);
}
/*
* Called with the highest fd that we know about. If it is 0, completely
* recalculate everything.
*/
int
poll_recalc(struct event_base *base, void *arg, int max)
{
struct pollop *pop = arg;
return (evsignal_recalc(&pop->evsigmask));
}
int
poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
{
int res, i, count, sec, nfds;
struct event *ev;
struct pollop *pop = arg;
count = pop->event_count;
nfds = 0;
TAILQ_FOREACH(ev, &base->eventqueue, ev_next) {
if (nfds + 1 >= count) {
if (count < 32)
count = 32;
else
count *= 2;
/* We need more file descriptors */
pop->event_set = realloc(pop->event_set,
count * sizeof(struct pollfd));
if (pop->event_set == NULL) {
event_warn("realloc");
return (-1);
}
pop->event_back = realloc(pop->event_back,
count * sizeof(struct event *));
if (pop->event_back == NULL) {
event_warn("realloc");
return (-1);
}
pop->event_count = count;
}
if (ev->ev_events & EV_WRITE) {
struct pollfd *pfd = &pop->event_set[nfds];
pfd->fd = ev->ev_fd;
pfd->events = POLLOUT;
pfd->revents = 0;
pop->event_back[nfds] = ev;
nfds++;
}
if (ev->ev_events & EV_READ) {
struct pollfd *pfd = &pop->event_set[nfds];
pfd->fd = ev->ev_fd;
pfd->events = POLLIN;
pfd->revents = 0;
pop->event_back[nfds] = ev;
nfds++;
}
}
if (evsignal_deliver(&pop->evsigmask) == -1)
return (-1);
sec = tv->tv_sec * 1000 + (tv->tv_usec + 999) / 1000;
res = poll(pop->event_set, nfds, sec);
if (evsignal_recalc(&pop->evsigmask) == -1)
return (-1);
if (res == -1) {
if (errno != EINTR) {
event_warn("poll");
return (-1);
}
evsignal_process();
return (0);
} else if (evsignal_caught)
evsignal_process();
event_debug(("%s: poll reports %d", __func__, res));
if (res == 0)
return (0);
for (i = 0; i < nfds; i++) {
int what = pop->event_set[i].revents;
res = 0;
/* If the file gets closed notify */
if (what & POLLHUP)
what |= POLLIN|POLLOUT;
if (what & POLLERR)
what |= POLLIN|POLLOUT;
if (what & POLLIN)
res |= EV_READ;
if (what & POLLOUT)
res |= EV_WRITE;
if (res == 0)
continue;
ev = pop->event_back[i];
res &= ev->ev_events;
if (res) {
if (!(ev->ev_events & EV_PERSIST))
event_del(ev);
event_active(ev, res, 1);
}
}
return (0);
}
int
poll_add(void *arg, struct event *ev)
{
struct pollop *pop = arg;
if (ev->ev_events & EV_SIGNAL)
return (evsignal_add(&pop->evsigmask, ev));
return (0);
}
/*
* Nothing to be done here.
*/
int
poll_del(void *arg, struct event *ev)
{
struct pollop *pop = arg;
if (!(ev->ev_events & EV_SIGNAL))
return (0);
return (evsignal_del(&pop->evsigmask, ev));
}