/*
- * Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
- * Copyright (C) 2010 John Crispin <blogic@openwrt.org>
- * Copyright (C) 2010 Steven Barth <steven@midlink.org>
+ * uloop - event loop implementation
*
- * 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.
+ * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org>
*
- * 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.
+ * 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.
*/
-
#include <sys/time.h>
#include <sys/types.h>
#include <stdbool.h>
#include "uloop.h"
+#include "utils.h"
#ifdef USE_KQUEUE
#include <sys/event.h>
#endif
#include <sys/wait.h>
+struct uloop_fd_event {
+ struct uloop_fd *fd;
+ unsigned int events;
+};
+
+struct uloop_fd_stack {
+ struct uloop_fd_stack *next;
+ struct uloop_fd *fd;
+ unsigned int events;
+};
+
+static struct uloop_fd_stack *fd_stack = NULL;
-#ifndef ARRAY_SIZE
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
-#endif
#define ULOOP_MAX_EVENTS 10
static struct list_head timeouts = LIST_HEAD_INIT(timeouts);
static int poll_fd = -1;
bool uloop_cancelled = false;
-bool uloop_handle_sigchld = true;
static bool do_sigchld = false;
+
+static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS];
static int cur_fd, cur_nfds;
#ifdef USE_KQUEUE
int uloop_init(void)
{
+ struct timespec timeout = { 0, 0 };
+ struct kevent ev = {};
+
if (poll_fd >= 0)
return 0;
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 struct kevent events[ULOOP_MAX_EVENTS];
-static int register_poll(struct uloop_fd *fd, unsigned int flags)
+static int register_kevent(struct uloop_fd *fd, unsigned int flags)
{
struct timespec timeout = { 0, 0 };
struct kevent ev[2];
- unsigned int changed;
int nev = 0;
unsigned int fl = 0;
+ unsigned int changed;
+ uint16_t kflags;
- changed = fd->kqflags ^ flags;
+ if (flags & ULOOP_EDGE_DEFER)
+ flags &= ~ULOOP_EDGE_TRIGGER;
+
+ changed = flags ^ fd->flags;
if (changed & ULOOP_EDGE_TRIGGER)
changed |= flags;
if (changed & ULOOP_READ) {
- uint16_t kflags = get_flags(flags, ULOOP_READ);
+ kflags = get_flags(flags, ULOOP_READ);
EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd);
}
if (changed & ULOOP_WRITE) {
- uint16_t kflags = get_flags(flags, 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;
- if (nev && (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1))
+ fd->flags = flags;
+ if (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1)
return -1;
- fd->kqflags = flags;
return 0;
}
-int uloop_fd_delete(struct uloop_fd *sock)
+static int register_poll(struct uloop_fd *fd, unsigned int flags)
{
- int i;
-
- for (i = cur_fd + 1; i < cur_nfds; i++) {
- if (events[i].udata != sock)
- continue;
+ if (flags & ULOOP_EDGE_TRIGGER)
+ flags |= ULOOP_EDGE_DEFER;
+ else
+ flags &= ~ULOOP_EDGE_DEFER;
- events[i].udata = NULL;
- }
+ return register_kevent(fd, flags);
+}
- sock->registered = false;
- return register_poll(sock, 0);
+static int __uloop_fd_delete(struct uloop_fd *fd)
+{
+ return register_poll(fd, 0);
}
-static void uloop_run_events(int timeout)
+static int uloop_fetch_events(int timeout)
{
struct timespec ts;
int nfds, n;
- if (timeout > 0) {
+ 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)
- {
+ 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;
- uloop_fd_delete(u);
+ if (!(u->flags & ULOOP_ERROR_CB))
+ uloop_fd_delete(u);
}
if(events[n].filter == EVFILT_READ)
if (events[n].flags & EV_EOF)
u->eof = true;
else if (!ev)
- continue;
+ cur->fd = NULL;
- if (u->cb) {
- cur_fd = n;
- cur_nfds = nfds;
- u->cb(u, ev);
+ cur->events = ev;
+ if (u->flags & ULOOP_EDGE_DEFER) {
+ u->flags &= ~ULOOP_EDGE_DEFER;
+ u->flags |= ULOOP_EDGE_TRIGGER;
+ register_kevent(u, u->flags);
}
}
- cur_nfds = 0;
+ return nfds;
}
#endif
ev.data.fd = fd->fd;
ev.data.ptr = fd;
+ fd->flags = flags;
return epoll_ctl(poll_fd, op, fd->fd, &ev);
}
static struct epoll_event events[ULOOP_MAX_EVENTS];
-int uloop_fd_delete(struct uloop_fd *sock)
+static int __uloop_fd_delete(struct uloop_fd *sock)
{
- int i;
-
- for (i = cur_fd + 1; i < cur_nfds; i++) {
- if (events[i].data.ptr != sock)
- continue;
-
- events[i].data.ptr = NULL;
- }
- sock->registered = false;
+ sock->flags = 0;
return epoll_ctl(poll_fd, EPOLL_CTL_DEL, sock->fd, 0);
}
-static void uloop_run_events(int timeout)
+static int uloop_fetch_events(int timeout)
{
int n, nfds;
nfds = epoll_wait(poll_fd, events, ARRAY_SIZE(events), timeout);
- for(n = 0; n < nfds; ++n)
- {
+ for (n = 0; n < nfds; ++n) {
+ struct uloop_fd_event *cur = &cur_fds[n];
struct uloop_fd *u = events[n].data.ptr;
unsigned int ev = 0;
+ cur->fd = u;
if (!u)
continue;
- if(events[n].events & (EPOLLERR|EPOLLHUP)) {
+ if (events[n].events & (EPOLLERR|EPOLLHUP)) {
u->error = true;
- uloop_fd_delete(u);
+ if (!(u->flags & ULOOP_ERROR_CB))
+ uloop_fd_delete(u);
}
- if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP)))
+ if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP))) {
+ cur->fd = NULL;
continue;
+ }
if(events[n].events & EPOLLRDHUP)
u->eof = true;
if(events[n].events & EPOLLOUT)
ev |= ULOOP_WRITE;
- if(u->cb) {
- cur_fd = n;
- cur_nfds = nfds;
- u->cb(u, ev);
- }
+ cur->events = ev;
}
- cur_nfds = 0;
+
+ return nfds;
}
#endif
+static bool uloop_fd_stack_event(struct uloop_fd *fd, int events)
+{
+ struct uloop_fd_stack *cur;
+
+ /*
+ * Do not buffer events for level-triggered fds, they will keep firing.
+ * Caller needs to take care of recursion issues.
+ */
+ if (!(fd->flags & ULOOP_EDGE_TRIGGER))
+ return false;
+
+ for (cur = fd_stack; cur; cur = cur->next) {
+ if (cur->fd != fd)
+ continue;
+
+ if (events < 0)
+ cur->fd = NULL;
+ else
+ cur->events |= events | ULOOP_EVENT_BUFFERED;
+
+ return true;
+ }
+
+ return false;
+}
+
+static void uloop_run_events(int timeout)
+{
+ struct uloop_fd_event *cur;
+ struct uloop_fd *fd;
+
+ if (!cur_nfds) {
+ cur_fd = 0;
+ cur_nfds = uloop_fetch_events(timeout);
+ if (cur_nfds < 0)
+ cur_nfds = 0;
+ }
+
+ while (cur_nfds > 0) {
+ struct uloop_fd_stack stack_cur;
+ unsigned int events;
+
+ cur = &cur_fds[cur_fd++];
+ cur_nfds--;
+
+ fd = cur->fd;
+ events = cur->events;
+ if (!fd)
+ continue;
+
+ if (!fd->cb)
+ continue;
+
+ if (uloop_fd_stack_event(fd, cur->events))
+ continue;
+
+ stack_cur.next = fd_stack;
+ stack_cur.fd = fd;
+ fd_stack = &stack_cur;
+ do {
+ stack_cur.events = 0;
+ fd->cb(fd, events);
+ events = stack_cur.events & ULOOP_EVENT_MASK;
+ } while (stack_cur.fd && events);
+ fd_stack = stack_cur.next;
+
+ return;
+ }
+}
+
int uloop_fd_add(struct uloop_fd *sock, unsigned int flags)
{
unsigned int fl;
int ret;
+ if (!(flags & (ULOOP_READ | ULOOP_WRITE)))
+ return uloop_fd_delete(sock);
+
if (!sock->registered && !(flags & ULOOP_BLOCKING)) {
fl = fcntl(sock->fd, F_GETFL, 0);
fl |= O_NONBLOCK;
sock->registered = true;
sock->eof = false;
+ sock->error = false;
out:
return ret;
}
+int uloop_fd_delete(struct uloop_fd *fd)
+{
+ int i;
+
+ for (i = 0; i < cur_nfds; i++) {
+ if (cur_fds[cur_fd + i].fd != fd)
+ continue;
+
+ cur_fds[cur_fd + i].fd = NULL;
+ }
+
+ if (!fd->registered)
+ return 0;
+
+ fd->registered = false;
+ uloop_fd_stack_event(fd, -1);
+ return __uloop_fd_delete(fd);
+}
+
static int tv_diff(struct timeval *t1, struct timeval *t2)
{
- if (t1->tv_sec != t2->tv_sec)
- return (t1->tv_sec - t2->tv_sec) * 1000;
- else
- return (t1->tv_usec - t2->tv_usec) / 1000;
+ return
+ (t1->tv_sec - t2->tv_sec) * 1000 +
+ (t1->tv_usec - t2->tv_usec) / 1000;
}
int uloop_timeout_add(struct uloop_timeout *timeout)
return 0;
}
+static void uloop_gettime(struct timeval *tv)
+{
+ struct timespec ts;
+
+ clock_gettime(CLOCK_MONOTONIC, &ts);
+ tv->tv_sec = ts.tv_sec;
+ tv->tv_usec = ts.tv_nsec / 1000;
+}
+
int uloop_timeout_set(struct uloop_timeout *timeout, int msecs)
{
struct timeval *time = &timeout->time;
if (timeout->pending)
uloop_timeout_cancel(timeout);
- gettimeofday(&timeout->time, NULL);
+ uloop_gettime(time);
time->tv_sec += msecs / 1000;
time->tv_usec += (msecs % 1000) * 1000;
if (time->tv_usec > 1000000) {
time->tv_sec++;
- time->tv_usec %= 1000000;
+ time->tv_usec -= 1000000;
}
return uloop_timeout_add(timeout);
return 0;
}
+int uloop_timeout_remaining(struct uloop_timeout *timeout)
+{
+ struct timeval now;
+
+ if (!timeout->pending)
+ return -1;
+
+ uloop_gettime(&now);
+
+ return tv_diff(&timeout->time, &now);
+}
+
int uloop_process_add(struct uloop_process *p)
{
struct uloop_process *tmp;
do_sigchld = true;
}
-static void uloop_setup_signals(void)
+static void uloop_install_handler(int signum, void (*handler)(int), struct sigaction* old, bool add)
+{
+ struct sigaction s;
+ struct sigaction *act;
+
+ act = NULL;
+ sigaction(signum, NULL, &s);
+
+ if (add) {
+ if (s.sa_handler == SIG_DFL) { /* Do not override existing custom signal handlers */
+ memcpy(old, &s, sizeof(struct sigaction));
+ s.sa_handler = handler;
+ s.sa_flags = 0;
+ act = &s;
+ }
+ }
+ else if (s.sa_handler == handler) { /* Do not restore if someone modified our handler */
+ act = old;
+ }
+
+ if (act != NULL)
+ sigaction(signum, act, NULL);
+}
+
+static void uloop_ignore_signal(int signum, bool ignore)
{
struct sigaction s;
+ void *new_handler = NULL;
+
+ sigaction(signum, NULL, &s);
- memset(&s, 0, sizeof(struct sigaction));
- s.sa_handler = uloop_handle_sigint;
- s.sa_flags = 0;
- sigaction(SIGINT, &s, NULL);
+ if (ignore) {
+ if (s.sa_handler == SIG_DFL) /* Ignore only if there isn't any custom handler */
+ new_handler = SIG_IGN;
+ } else {
+ if (s.sa_handler == SIG_IGN) /* Restore only if noone modified our SIG_IGN */
+ new_handler = SIG_DFL;
+ }
- if (uloop_handle_sigchld) {
- s.sa_handler = uloop_sigchld;
- sigaction(SIGCHLD, &s, NULL);
+ if (new_handler) {
+ s.sa_handler = new_handler;
+ s.sa_flags = 0;
+ sigaction(signum, &s, NULL);
}
}
+static void uloop_setup_signals(bool add)
+{
+ static struct sigaction old_sigint, old_sigchld, old_sigterm;
+
+ uloop_install_handler(SIGINT, uloop_handle_sigint, &old_sigint, add);
+ uloop_install_handler(SIGTERM, uloop_handle_sigint, &old_sigterm, add);
+ uloop_install_handler(SIGCHLD, uloop_sigchld, &old_sigchld, add);
+
+ uloop_ignore_signal(SIGPIPE, add);
+}
+
static int uloop_get_next_timeout(struct timeval *tv)
{
struct uloop_timeout *timeout;
void uloop_run(void)
{
+ static int recursive_calls = 0;
struct timeval tv;
- uloop_setup_signals();
+ /*
+ * Handlers are only updated for the first call to uloop_run() (and restored
+ * when this call is done).
+ */
+ if (!recursive_calls++)
+ uloop_setup_signals(true);
+
+ uloop_cancelled = false;
while(!uloop_cancelled)
{
- gettimeofday(&tv, NULL);
+ uloop_gettime(&tv);
uloop_process_timeouts(&tv);
- if (uloop_cancelled)
- break;
if (do_sigchld)
uloop_handle_processes();
+
+ if (uloop_cancelled)
+ break;
+
+ uloop_gettime(&tv);
uloop_run_events(uloop_get_next_timeout(&tv));
}
+
+ if (!--recursive_calls)
+ uloop_setup_signals(false);
}
void uloop_done(void)
projects / project / libubox.git / blobdiff