solanum-vs-hackint-and-char.../libratbox/src/epoll.c
2008-12-22 12:49:01 +03:00

577 lines
11 KiB
C

/*
* ircd-ratbox: A slightly useful ircd.
* epoll.c: Linux epoll 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
* Copyright (C) 2002 Aaron Sethman <androsyn@ratbox.org>
*
* 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: epoll.c 26294 2008-12-13 03:01:19Z androsyn $
*/
#define _GNU_SOURCE 1
#include <libratbox_config.h>
#include <ratbox_lib.h>
#include <commio-int.h>
#include <event-int.h>
#if defined(HAVE_EPOLL_CTL) && (HAVE_SYS_EPOLL_H)
#define USING_EPOLL
#include <fcntl.h>
#include <sys/epoll.h>
#if defined(HAVE_SIGNALFD) && (HAVE_SYS_SIGNALFD_H) && (USE_TIMER_CREATE) && (HAVE_SYS_UIO_H)
#include <signal.h>
#include <sys/signalfd.h>
#include <sys/uio.h>
#define EPOLL_SCHED_EVENT 1
#endif
#if defined(USE_TIMERFD_CREATE)
#include <sys/timerfd.h>
#endif
#define RTSIGNAL SIGRTMIN
struct epoll_info
{
int ep;
struct epoll_event *pfd;
int pfd_size;
};
static struct epoll_info *ep_info;
static int can_do_event;
static int can_do_timerfd;
/*
* rb_init_netio
*
* This is a needed exported function which will be called to initialise
* the network loop code.
*/
int
rb_init_netio_epoll(void)
{
can_do_event = 0; /* shut up gcc */
can_do_timerfd = 0;
ep_info = rb_malloc(sizeof(struct epoll_info));
ep_info->pfd_size = getdtablesize();
ep_info->ep = epoll_create(ep_info->pfd_size);
if(ep_info->ep < 0)
{
return -1;
}
rb_open(ep_info->ep, RB_FD_UNKNOWN, "epoll file descriptor");
ep_info->pfd = rb_malloc(sizeof(struct epoll_event) * ep_info->pfd_size);
return 0;
}
int
rb_setup_fd_epoll(rb_fde_t *F)
{
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_epoll(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
struct epoll_event ep_event;
int old_flags = F->pflags;
int op = -1;
lrb_assert(IsFDOpen(F));
/* Update the list, even though we're not using it .. */
if(type & RB_SELECT_READ)
{
if(handler != NULL)
F->pflags |= EPOLLIN;
else
F->pflags &= ~EPOLLIN;
F->read_handler = handler;
F->read_data = client_data;
}
if(type & RB_SELECT_WRITE)
{
if(handler != NULL)
F->pflags |= EPOLLOUT;
else
F->pflags &= ~EPOLLOUT;
F->write_handler = handler;
F->write_data = client_data;
}
if(old_flags == 0 && F->pflags == 0)
return;
else if(F->pflags <= 0)
op = EPOLL_CTL_DEL;
else if(old_flags == 0 && F->pflags > 0)
op = EPOLL_CTL_ADD;
else if(F->pflags != old_flags)
op = EPOLL_CTL_MOD;
if(op == -1)
return;
ep_event.events = F->pflags;
ep_event.data.ptr = F;
if(op == EPOLL_CTL_ADD || op == EPOLL_CTL_MOD)
ep_event.events |= EPOLLET;
if(epoll_ctl(ep_info->ep, op, F->fd, &ep_event) != 0)
{
rb_lib_log("rb_setselect_epoll(): epoll_ctl failed: %s", strerror(errno));
abort();
}
}
/*
* 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_epoll(long delay)
{
int num, i, flags, old_flags, op;
struct epoll_event ep_event;
int o_errno;
void *data;
num = epoll_wait(ep_info->ep, ep_info->pfd, ep_info->pfd_size, delay);
/* save errno as rb_set_time() will likely clobber it */
o_errno = errno;
rb_set_time();
errno = o_errno;
if(num < 0 && !rb_ignore_errno(o_errno))
return RB_ERROR;
if(num <= 0)
return RB_OK;
for(i = 0; i < num; i++)
{
PF *hdl;
rb_fde_t *F = ep_info->pfd[i].data.ptr;
old_flags = F->pflags;
if(ep_info->pfd[i].events & (EPOLLIN | EPOLLHUP | EPOLLERR))
{
hdl = F->read_handler;
data = F->read_data;
F->read_handler = NULL;
F->read_data = NULL;
if(hdl)
{
hdl(F, data);
}
}
if(!IsFDOpen(F))
continue;
if(ep_info->pfd[i].events & (EPOLLOUT | EPOLLHUP | EPOLLERR))
{
hdl = F->write_handler;
data = F->write_data;
F->write_handler = NULL;
F->write_data = NULL;
if(hdl)
{
hdl(F, data);
}
}
if(!IsFDOpen(F))
continue;
flags = 0;
if(F->read_handler != NULL)
flags |= EPOLLIN;
if(F->write_handler != NULL)
flags |= EPOLLOUT;
if(old_flags != flags)
{
if(flags == 0)
op = EPOLL_CTL_DEL;
else
op = EPOLL_CTL_MOD;
F->pflags = ep_event.events = flags;
ep_event.data.ptr = F;
if(op == EPOLL_CTL_MOD || op == EPOLL_CTL_ADD)
ep_event.events |= EPOLLET;
if(epoll_ctl(ep_info->ep, op, F->fd, &ep_event) != 0)
{
rb_lib_log("rb_select_epoll(): epoll_ctl failed: %s",
strerror(errno));
}
}
}
return RB_OK;
}
#ifdef EPOLL_SCHED_EVENT
int
rb_epoll_supports_event(void)
{
/* try to detect at runtime if everything we need actually works */
timer_t timer;
struct sigevent ev;
int fd;
sigset_t set;
if(can_do_event == 1)
return 1;
if(can_do_event == -1)
return 0;
#ifdef USE_TIMERFD_CREATE
if((fd = timerfd_create(CLOCK_REALTIME, 0)) >= 0)
{
close(fd);
can_do_event = 1;
can_do_timerfd = 1;
return 1;
}
#endif
ev.sigev_signo = SIGVTALRM;
ev.sigev_notify = SIGEV_SIGNAL;
if(timer_create(CLOCK_REALTIME, &ev, &timer) != 0)
{
can_do_event = -1;
return 0;
}
timer_delete(timer);
sigemptyset(&set);
fd = signalfd(-1, &set, 0);
if(fd < 0)
{
can_do_event = -1;
return 0;
}
close(fd);
can_do_event = 1;
return 1;
}
/* bleh..work around a glibc header bug on 32bit systems */
struct our_signalfd_siginfo
{
uint32_t signo;
int32_t err;
int32_t code;
uint32_t pid;
uint32_t uid;
int32_t fd;
uint32_t tid;
uint32_t band;
uint32_t overrun;
uint32_t trapno;
int32_t status;
int32_t svint;
uint64_t svptr;
uint64_t utime;
uint64_t stime;
uint64_t addr;
uint8_t pad[48];
};
#define SIGFDIOV_COUNT 16
static void
signalfd_handler(rb_fde_t *F, void *data)
{
static struct our_signalfd_siginfo fdsig[SIGFDIOV_COUNT];
static struct iovec iov[SIGFDIOV_COUNT];
struct ev_entry *ev;
int ret, x;
for(x = 0; x < SIGFDIOV_COUNT; x++)
{
iov[x].iov_base = &fdsig[x];
iov[x].iov_len = sizeof(struct our_signalfd_siginfo);
}
while(1)
{
ret = readv(rb_get_fd(F), iov, SIGFDIOV_COUNT);
if(ret == 0 || (ret < 0 && !rb_ignore_errno(errno)))
{
rb_close(F);
rb_epoll_init_event();
return;
}
if(ret < 0)
{
rb_setselect(F, RB_SELECT_READ, signalfd_handler, NULL);
return;
}
for(x = 0; x < ret / (int)sizeof(struct our_signalfd_siginfo); x++)
{
#if __WORDSIZE == 32 && defined(__sparc__)
uint32_t *q = (uint32_t *)&fdsig[x].svptr;
ev = (struct ev_entry *)q[0];
#else
ev = (struct ev_entry *)(uintptr_t)(fdsig[x].svptr);
#endif
if(ev == NULL)
continue;
rb_run_event(ev);
}
}
}
void
rb_epoll_init_event(void)
{
sigset_t ss;
rb_fde_t *F;
int sfd;
rb_epoll_supports_event();
if(!can_do_timerfd)
{
sigemptyset(&ss);
sigaddset(&ss, RTSIGNAL);
sigprocmask(SIG_BLOCK, &ss, 0);
sigemptyset(&ss);
sigaddset(&ss, RTSIGNAL);
sfd = signalfd(-1, &ss, 0);
if(sfd == -1)
{
can_do_event = -1;
return;
}
F = rb_open(sfd, RB_FD_UNKNOWN, "signalfd");
rb_set_nb(F);
signalfd_handler(F, NULL);
}
}
static int
rb_epoll_sched_event_signalfd(struct ev_entry *event, int when)
{
timer_t *id;
struct sigevent ev;
struct itimerspec ts;
memset(&ev, 0, sizeof(&ev));
event->comm_ptr = rb_malloc(sizeof(timer_t));
id = event->comm_ptr;
ev.sigev_notify = SIGEV_SIGNAL;
ev.sigev_signo = RTSIGNAL;
ev.sigev_value.sival_ptr = event;
if(timer_create(CLOCK_REALTIME, &ev, id) < 0)
{
rb_lib_log("timer_create: %s\n", strerror(errno));
return 0;
}
memset(&ts, 0, sizeof(ts));
ts.it_value.tv_sec = when;
ts.it_value.tv_nsec = 0;
if(event->frequency != 0)
ts.it_interval = ts.it_value;
if(timer_settime(*id, 0, &ts, NULL) < 0)
{
rb_lib_log("timer_settime: %s\n", strerror(errno));
return 0;
}
return 1;
}
#ifdef USE_TIMERFD_CREATE
static void
rb_read_timerfd(rb_fde_t *F, void *data)
{
struct ev_entry *event = (struct ev_entry *)data;
int retlen;
uint64_t count;
if(event == NULL)
{
rb_close(F);
return;
}
retlen = rb_read(F, &count, sizeof(count));
if(retlen == 0 || (retlen < 0 && !rb_ignore_errno(errno)))
{
rb_close(F);
rb_lib_log("rb_read_timerfd: timerfd[%s] closed on error: %s", event->name,
strerror(errno));
return;
}
rb_setselect(F, RB_SELECT_READ, rb_read_timerfd, event);
rb_run_event(event);
}
static int
rb_epoll_sched_event_timerfd(struct ev_entry *event, int when)
{
struct itimerspec ts;
static char buf[FD_DESC_SZ + 8];
int fd;
rb_fde_t *F;
if((fd = timerfd_create(CLOCK_REALTIME, 0)) < 0)
{
rb_lib_log("timerfd_create: %s\n", strerror(errno));
return 0;
}
memset(&ts, 0, sizeof(ts));
ts.it_value.tv_sec = when;
ts.it_value.tv_nsec = 0;
if(event->frequency != 0)
ts.it_interval = ts.it_value;
if(timerfd_settime(fd, 0, &ts, NULL) < 0)
{
rb_lib_log("timerfd_settime: %s\n", strerror(errno));
close(fd);
return 0;
}
rb_snprintf(buf, sizeof(buf), "timerfd: %s", event->name);
F = rb_open(fd, RB_FD_UNKNOWN, buf);
rb_set_nb(F);
event->comm_ptr = F;
rb_setselect(F, RB_SELECT_READ, rb_read_timerfd, event);
return 1;
}
#endif
int
rb_epoll_sched_event(struct ev_entry *event, int when)
{
#ifdef USE_TIMERFD_CREATE
if(can_do_timerfd)
{
return rb_epoll_sched_event_timerfd(event, when);
}
#endif
return rb_epoll_sched_event_signalfd(event, when);
}
void
rb_epoll_unsched_event(struct ev_entry *event)
{
#ifdef USE_TIMERFD_CREATE
if(can_do_timerfd)
{
rb_close((rb_fde_t *)event->comm_ptr);
event->comm_ptr = NULL;
return;
}
#endif
timer_delete(*((timer_t *) event->comm_ptr));
rb_free(event->comm_ptr);
event->comm_ptr = NULL;
}
#endif /* EPOLL_SCHED_EVENT */
#else /* epoll not supported here */
int
rb_init_netio_epoll(void)
{
return ENOSYS;
}
void
rb_setselect_epoll(rb_fde_t *F, unsigned int type, PF * handler, void *client_data)
{
errno = ENOSYS;
return;
}
int
rb_select_epoll(long delay)
{
errno = ENOSYS;
return -1;
}
int
rb_setup_fd_epoll(rb_fde_t *F)
{
errno = ENOSYS;
return -1;
}
#endif
#if !defined(USING_EPOLL) || !defined(EPOLL_SCHED_EVENT)
void
rb_epoll_init_event(void)
{
return;
}
int
rb_epoll_sched_event(struct ev_entry *event, int when)
{
errno = ENOSYS;
return -1;
}
void
rb_epoll_unsched_event(struct ev_entry *event)
{
return;
}
int
rb_epoll_supports_event(void)
{
errno = ENOSYS;
return 0;
}
#endif /* !USING_EPOLL || !EPOLL_SCHED_EVENT */