elemental-ircd/libratbox/src/select.c

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/*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
* USA
*
*/
#define FD_SETSIZE 65535
#include <libratbox_config.h>
#include <ratbox_lib.h>
#include <commio-int.h>
#if defined(HAVE_SELECT) || defined(_WIN32)
#ifdef _WIN32
#define MY_FD_SET(x, y) FD_SET((SOCKET)x, y)
#define MY_FD_CLR(x, y) FD_CLR((SOCKET)x, y)
#else
#define MY_FD_SET(x, y) FD_SET(x, y)
#define MY_FD_CLR(x, y) FD_CLR(x, y)
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
/*
* 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
*/
static fd_set select_readfds;
static fd_set select_writefds;
/*
* You know, I'd rather have these local to rb_select but for some
* reason my gcc decides that I can't modify them at all..
* -- adrian
*/
static fd_set tmpreadfds;
static fd_set tmpwritefds;
static int rb_maxfd = -1;
static void select_update_selectfds(rb_fde_t *F, short event, PF * handler);
/* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* Private functions */
/*
* set and clear entries in the select array ..
*/
static void
select_update_selectfds(rb_fde_t *F, short event, PF * handler)
{
/* Update the read / write set */
if(event & RB_SELECT_READ) {
if(handler) {
MY_FD_SET(F->fd, &select_readfds);
F->pflags |= RB_SELECT_READ;
} else {
MY_FD_CLR(F->fd, &select_readfds);
F->pflags &= ~RB_SELECT_READ;
}
}
if(event & RB_SELECT_WRITE) {
if(handler) {
MY_FD_SET(F->fd, &select_writefds);
F->pflags |= RB_SELECT_WRITE;
} else {
MY_FD_CLR(F->fd, &select_writefds);
F->pflags &= ~RB_SELECT_WRITE;
}
}
if(F->pflags & (RB_SELECT_READ | RB_SELECT_WRITE)) {
if(F->fd > rb_maxfd) {
rb_maxfd = F->fd;
}
} else if(F->fd <= rb_maxfd) {
while(rb_maxfd >= 0 && !FD_ISSET(rb_maxfd, &select_readfds)
&& !FD_ISSET(rb_maxfd, &select_writefds))
rb_maxfd--;
}
}
/* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
/* Public functions */
int
rb_setup_fd_select(rb_fde_t *F)
{
return 0;
}
/*
* rb_init_netio
*
* This is a needed exported function which will be called to initialise
* the network loop code.
*/
extern int rb_maxconnections;
int
rb_init_netio_select(void)
{
if(rb_maxconnections > FD_SETSIZE)
rb_maxconnections = FD_SETSIZE; /* override this */
FD_ZERO(&select_readfds);
FD_ZERO(&select_writefds);
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_select(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
lrb_assert(IsFDOpen(F));
if(type & RB_SELECT_READ) {
F->read_handler = handler;
F->read_data = client_data;
select_update_selectfds(F, RB_SELECT_READ, handler);
}
if(type & RB_SELECT_WRITE) {
F->write_handler = handler;
F->write_data = client_data;
select_update_selectfds(F, RB_SELECT_WRITE, handler);
}
}
/*
* 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
*
* Do IO events
*/
int
rb_select_select(long delay)
{
int num;
int fd;
PF *hdl;
rb_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(rb_maxfd + 1, &tmpreadfds, &tmpwritefds, NULL, &to);
if(num >= 0)
break;
if(rb_ignore_errno(errno))
continue;
rb_set_time();
/* error! */
return -1;
/* NOTREACHED */
}
rb_set_time();
if(num == 0)
return 0;
/* XXX we *could* optimise by falling out after doing num fds ... */
for(fd = 0; fd < rb_maxfd + 1; fd++) {
F = rb_find_fd(fd);
if(F == NULL)
continue;
if(FD_ISSET(fd, &tmpreadfds)) {
hdl = F->read_handler;
F->read_handler = NULL;
if(hdl)
hdl(F, F->read_data);
}
if(!IsFDOpen(F))
continue; /* Read handler closed us..go on */
if(FD_ISSET(fd, &tmpwritefds)) {
hdl = F->write_handler;
F->write_handler = NULL;
if(hdl)
hdl(F, F->write_data);
}
if(F->read_handler == NULL)
select_update_selectfds(F, RB_SELECT_READ, NULL);
if(F->write_handler == NULL)
select_update_selectfds(F, RB_SELECT_WRITE, NULL);
}
return 0;
}
#else /* select not supported..what sort of garbage is this? */
int
rb_init_netio_select(void)
{
return ENOSYS;
}
void
rb_setselect_select(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
errno = ENOSYS;
return;
}
int
rb_select_select(long delay)
{
errno = ENOSYS;
return -1;
}
int
rb_setup_fd_select(rb_fde_t *F)
{
errno = ENOSYS;
return -1;
}
#endif