elemental-ircd/libratbox/src/devpoll.c

300 lines
6.7 KiB
C

/*
* ircd-ratbox: A slightly useful ircd.
* s_bsd_devpoll.c: /dev/poll compatible network routines.
*
* Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
* Copyright (C) 1996-2002 Hybrid Development Team
* Copyright (C) 2001 Adrian Chadd <adrian@creative.net.au>
* Copyright (C) 2002-2005 ircd-ratbox development team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
* USA
*
* $Id: devpoll.c 26254 2008-12-10 04:04:38Z androsyn $
*/
#include <libratbox_config.h>
#include <ratbox_lib.h>
#include <commio-int.h>
#include <fcntl.h>
#if defined(HAVE_DEVPOLL) && (HAVE_SYS_DEVPOLL_H)
#include <sys/devpoll.h>
static int dpfd;
static int maxfd;
static short *fdmask;
static void devpoll_update_events(rb_fde_t *, short, PF *);
static void devpoll_write_update(int, int);
int
rb_setup_fd_devpoll(rb_fde_t *F)
{
return 0;
}
/*
* Write an update to the devpoll filter.
* See, we end up having to do a seperate (?) remove before we do an
* add of a new polltype, so we have to have this function seperate from
* the others.
*/
static void
devpoll_write_update(int fd, int events)
{
struct pollfd pollfds[1]; /* Just to be careful */
int retval;
/* Build the pollfd entry */
pollfds[0].revents = 0;
pollfds[0].fd = fd;
pollfds[0].events = events;
/* Write the thing to our poll fd */
retval = write(dpfd, &pollfds[0], sizeof(struct pollfd));
if(retval != sizeof(struct pollfd))
rb_lib_log("devpoll_write_update: dpfd write failed %d: %s", errno,
strerror(errno));
/* Done! */
}
static void
devpoll_update_events(rb_fde_t *F, short filter, PF * handler)
{
int update_required = 0;
int fd = rb_get_fd(F);
int cur_mask = fdmask[fd];
PF *cur_handler;
fdmask[fd] = 0;
switch (filter)
{
case RB_SELECT_READ:
cur_handler = F->read_handler;
if(handler)
fdmask[fd] |= POLLRDNORM;
else
fdmask[fd] &= ~POLLRDNORM;
if(F->write_handler)
fdmask[fd] |= POLLWRNORM;
break;
case RB_SELECT_WRITE:
cur_handler = F->write_handler;
if(handler)
fdmask[fd] |= POLLWRNORM;
else
fdmask[fd] &= ~POLLWRNORM;
if(F->read_handler)
fdmask[fd] |= POLLRDNORM;
break;
default:
return;
break;
}
if(cur_handler == NULL && handler != NULL)
update_required++;
else if(cur_handler != NULL && handler == NULL)
update_required++;
if(cur_mask != fdmask[fd])
update_required++;
if(update_required)
{
/*
* Ok, we can call devpoll_write_update() here now to re-build the
* fd struct. If we end up with nothing on this fd, it won't write
* anything.
*/
if(fdmask[fd])
{
devpoll_write_update(fd, POLLREMOVE);
devpoll_write_update(fd, fdmask[fd]);
}
else
devpoll_write_update(fd, POLLREMOVE);
}
}
/* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* Public functions */
/*
* rb_init_netio
*
* This is a needed exported function which will be called to initialise
* the network loop code.
*/
int
rb_init_netio_devpoll(void)
{
dpfd = open("/dev/poll", O_RDWR);
if(dpfd < 0)
{
return errno;
}
maxfd = getdtablesize() - 2; /* This makes more sense than HARD_FDLIMIT */
fdmask = rb_malloc(sizeof(fdmask) * maxfd + 1);
rb_open(dpfd, RB_FD_UNKNOWN, "/dev/poll file descriptor");
return 0;
}
/*
* rb_setselect
*
* This is a needed exported function which will be called to register
* and deregister interest in a pending IO state for a given FD.
*/
void
rb_setselect_devpoll(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
lrb_assert(IsFDOpen(F));
if(type & RB_SELECT_READ)
{
devpoll_update_events(F, RB_SELECT_READ, handler);
F->read_handler = handler;
F->read_data = client_data;
}
if(type & RB_SELECT_WRITE)
{
devpoll_update_events(F, RB_SELECT_WRITE, handler);
F->write_handler = handler;
F->write_data = client_data;
}
}
/*
* Check all connections for new connections and input data that is to be
* processed. Also check for connections with data queued and whether we can
* write it out.
*/
/*
* rb_select
*
* Called to do the new-style IO, courtesy of squid (like most of this
* new IO code). This routine handles the stuff we've hidden in
* rb_setselect and fd_table[] and calls callbacks for IO ready
* events.
*/
int
rb_select_devpoll(long delay)
{
int num, i;
struct pollfd pollfds[maxfd];
struct dvpoll dopoll;
do
{
for(;;)
{
dopoll.dp_timeout = delay;
dopoll.dp_nfds = maxfd;
dopoll.dp_fds = &pollfds[0];
num = ioctl(dpfd, DP_POLL, &dopoll);
if(num >= 0)
break;
if(rb_ignore_errno(errno))
break;
rb_set_time();
return RB_ERROR;
}
rb_set_time();
if(num == 0)
continue;
for(i = 0; i < num; i++)
{
int fd = dopoll.dp_fds[i].fd;
PF *hdl = NULL;
rb_fde_t *F = rb_find_fd(fd);
if((dopoll.dp_fds[i].revents & (POLLRDNORM | POLLIN | POLLHUP |
POLLERR))
&& (dopoll.dp_fds[i].events & (POLLRDNORM | POLLIN)))
{
if((hdl = F->read_handler) != NULL)
{
F->read_handler = NULL;
hdl(F, F->read_data);
/*
* this call used to be with a NULL pointer, BUT
* in the devpoll case we only want to update the
* poll set *if* the handler changes state (active ->
* NULL or vice versa.)
*/
devpoll_update_events(F, RB_SELECT_READ, F->read_handler);
}
}
if(!IsFDOpen(F))
continue; /* Read handler closed us..go on to do something more useful */
if((dopoll.dp_fds[i].revents & (POLLWRNORM | POLLOUT | POLLHUP |
POLLERR))
&& (dopoll.dp_fds[i].events & (POLLWRNORM | POLLOUT)))
{
if((hdl = F->write_handler) != NULL)
{
F->write_handler = NULL;
hdl(F, F->write_data);
/* See above similar code in the read case */
devpoll_update_events(F,
RB_SELECT_WRITE, F->write_handler);
}
}
}
return RB_OK;
}
while(0);
/* XXX Get here, we broke! */
return 0;
}
#else /* /dev/poll not supported */
int
rb_init_netio_devpoll(void)
{
return ENOSYS;
}
void
rb_setselect_devpoll(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
errno = ENOSYS;
return;
}
int
rb_select_devpoll(long delay)
{
errno = ENOSYS;
return -1;
}
int
rb_setup_fd_devpoll(rb_fde_t *F)
{
errno = ENOSYS;
return -1;
}
#endif