elemental-ircd/libcharybdis/select.c

201 lines
4.6 KiB
C

/*
* ircd-ratbox: A slightly useful ircd.
* select.c: select() 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* $Id: select.c 3354 2007-04-03 09:21:31Z nenolod $
*/
#include "config.h"
#include "libcharybdis.h"
/*
* Note that this is only a single list - multiple lists is kinda pointless
* under select because the list size is a function of the highest FD :-)
* -- adrian
*/
fd_set select_readfds;
fd_set select_writefds;
/*
* You know, I'd rather have these local to comm_select but for some
* reason my gcc decides that I can't modify them at all..
* -- adrian
*/
fd_set tmpreadfds;
fd_set tmpwritefds;
static void select_update_selectfds(int fd, short event, PF * handler);
/* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* Private functions */
/*
* set and clear entries in the select array ..
*/
static void
select_update_selectfds(int fd, short event, PF * handler)
{
/* Update the read / write set */
if(event & COMM_SELECT_READ)
{
if(handler)
FD_SET(fd, &select_readfds);
else
FD_CLR(fd, &select_readfds);
}
if(event & COMM_SELECT_WRITE)
{
if(handler)
FD_SET(fd, &select_writefds);
else
FD_CLR(fd, &select_writefds);
}
}
/* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* Public functions */
/*
* init_netio
*
* This is a needed exported function which will be called to initialise
* the network loop code.
*/
void
init_netio(void)
{
FD_ZERO(&select_readfds);
FD_ZERO(&select_writefds);
}
/*
* comm_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
comm_setselect(int fd, fdlist_t list, unsigned int type, PF * handler,
void *client_data, time_t timeout)
{
fde_t *F = comm_locate_fd(fd);
s_assert(fd >= 0);
s_assert(F->flags.open);
if(type & COMM_SELECT_READ)
{
F->read_handler = handler;
F->read_data = client_data;
select_update_selectfds(fd, COMM_SELECT_READ, handler);
}
if(type & COMM_SELECT_WRITE)
{
F->write_handler = handler;
F->write_data = client_data;
select_update_selectfds(fd, COMM_SELECT_WRITE, handler);
}
if(timeout)
F->timeout = CurrentTime + (timeout / 1000);
}
/*
* 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.
*/
/*
* comm_select
*
* Do IO events
*/
int
comm_select(unsigned long delay)
{
int num;
int fd;
PF *hdl;
fde_t *F;
struct timeval to;
/* Copy over the read/write sets so we don't have to rebuild em */
memcpy(&tmpreadfds, &select_readfds, sizeof(fd_set));
memcpy(&tmpwritefds, &select_writefds, sizeof(fd_set));
for (;;)
{
to.tv_sec = 0;
to.tv_usec = delay * 1000;
num = select(highest_fd + 1, &tmpreadfds, &tmpwritefds, NULL, &to);
if(num >= 0)
break;
if(ignoreErrno(errno))
continue;
set_time();
/* error! */
return -1;
/* NOTREACHED */
}
set_time();
if(num == 0)
return 0;
/* XXX we *could* optimise by falling out after doing num fds ... */
for (fd = 0; fd < highest_fd + 1; fd++)
{
F = comm_locate_fd(fd);
if(FD_ISSET(fd, &tmpreadfds))
{
hdl = F->read_handler;
F->read_handler = NULL;
if(hdl)
hdl(fd, F->read_data);
}
if(F->flags.open == 0)
continue; /* Read handler closed us..go on */
if(FD_ISSET(fd, &tmpwritefds))
{
hdl = F->write_handler;
F->write_handler = NULL;
if(hdl)
hdl(fd, F->write_data);
}
if(F->read_handler == NULL)
select_update_selectfds(fd, COMM_SELECT_READ, NULL);
if(F->write_handler == NULL)
select_update_selectfds(fd, COMM_SELECT_WRITE, NULL);
}
return 0;
}