libubox/uloop-kqueue.c
Felix Fietkau 1257a38a6e uloop: revert signalfd support for now
It hasn't fixed the reported race condition and it introduced some new
issues.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
2016-05-19 10:59:48 +02:00

148 lines
3.3 KiB
C

/*
* uloop - event loop implementation
*
* Copyright (C) 2010-2016 Felix Fietkau <nbd@openwrt.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
int uloop_init(void)
{
struct timespec timeout = { 0, 0 };
struct kevent ev = {};
if (poll_fd >= 0)
return 0;
poll_fd = kqueue();
if (poll_fd < 0)
return -1;
EV_SET(&ev, SIGCHLD, EVFILT_SIGNAL, EV_ADD, 0, 0, 0);
kevent(poll_fd, &ev, 1, NULL, 0, &timeout);
return 0;
}
static uint16_t get_flags(unsigned int flags, unsigned int mask)
{
uint16_t kflags = 0;
if (!(flags & mask))
return EV_DELETE;
kflags = EV_ADD;
if (flags & ULOOP_EDGE_TRIGGER)
kflags |= EV_CLEAR;
return kflags;
}
static struct kevent events[ULOOP_MAX_EVENTS];
static int register_kevent(struct uloop_fd *fd, unsigned int flags)
{
struct timespec timeout = { 0, 0 };
struct kevent ev[2];
int nev = 0;
unsigned int fl = 0;
unsigned int changed;
uint16_t kflags;
if (flags & ULOOP_EDGE_DEFER)
flags &= ~ULOOP_EDGE_TRIGGER;
changed = flags ^ fd->flags;
if (changed & ULOOP_EDGE_TRIGGER)
changed |= flags;
if (changed & ULOOP_READ) {
kflags = get_flags(flags, ULOOP_READ);
EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd);
}
if (changed & ULOOP_WRITE) {
kflags = get_flags(flags, ULOOP_WRITE);
EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd);
}
if (!flags)
fl |= EV_DELETE;
fd->flags = flags;
if (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1)
return -1;
return 0;
}
static int register_poll(struct uloop_fd *fd, unsigned int flags)
{
if (flags & ULOOP_EDGE_TRIGGER)
flags |= ULOOP_EDGE_DEFER;
else
flags &= ~ULOOP_EDGE_DEFER;
return register_kevent(fd, flags);
}
static int __uloop_fd_delete(struct uloop_fd *fd)
{
return register_poll(fd, 0);
}
static int uloop_fetch_events(int timeout)
{
struct timespec ts;
int nfds, n;
if (timeout >= 0) {
ts.tv_sec = timeout / 1000;
ts.tv_nsec = (timeout % 1000) * 1000000;
}
nfds = kevent(poll_fd, NULL, 0, events, ARRAY_SIZE(events), timeout >= 0 ? &ts : NULL);
for (n = 0; n < nfds; n++) {
struct uloop_fd_event *cur = &cur_fds[n];
struct uloop_fd *u = events[n].udata;
unsigned int ev = 0;
cur->fd = u;
if (!u)
continue;
if (events[n].flags & EV_ERROR) {
u->error = true;
if (!(u->flags & ULOOP_ERROR_CB))
uloop_fd_delete(u);
}
if(events[n].filter == EVFILT_READ)
ev |= ULOOP_READ;
else if (events[n].filter == EVFILT_WRITE)
ev |= ULOOP_WRITE;
if (events[n].flags & EV_EOF)
u->eof = true;
else if (!ev)
cur->fd = NULL;
cur->events = ev;
if (u->flags & ULOOP_EDGE_DEFER) {
u->flags &= ~ULOOP_EDGE_DEFER;
u->flags |= ULOOP_EDGE_TRIGGER;
register_kevent(u, u->flags);
}
}
return nfds;
}