/*
- * 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) 2010-2016 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 "uloop.h"
-
-#ifdef USE_KQUEUE
-#include <sys/event.h>
-#endif
-#ifdef USE_EPOLL
-#include <sys/epoll.h>
-#endif
-
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <poll.h>
#include <string.h>
#include <fcntl.h>
-#include <signal.h>
#include <stdbool.h>
-#ifndef ARRAY_SIZE
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
-#endif
-#define ULOOP_MAX_EVENTS 10
-
-struct uloop_timeout *first_timeout;
-static int poll_fd;
-bool uloop_cancelled = false;
+#include "uloop.h"
+#include "utils.h"
#ifdef USE_KQUEUE
+#include <sys/event.h>
+#endif
+#ifdef USE_EPOLL
+#include <sys/epoll.h>
+#endif
+#include <sys/wait.h>
-int uloop_init(void)
-{
- poll_fd = kqueue();
- if (poll_fd < 0)
- return -1;
+struct uloop_fd_event {
+ struct uloop_fd *fd;
+ unsigned int events;
+};
- return 0;
-}
+struct uloop_fd_stack {
+ struct uloop_fd_stack *next;
+ struct uloop_fd *fd;
+ unsigned int events;
+};
+static struct uloop_fd_stack *fd_stack = NULL;
-static uint16_t get_flags(unsigned int flags, unsigned int mask)
-{
- uint16_t kflags = 0;
+#define ULOOP_MAX_EVENTS 10
- if (!(flags & mask))
- return EV_DELETE;
+static struct list_head timeouts = LIST_HEAD_INIT(timeouts);
+static struct list_head processes = LIST_HEAD_INIT(processes);
- kflags = EV_ADD;
- if (flags & ULOOP_EDGE_TRIGGER)
- kflags |= EV_CLEAR;
+static int poll_fd = -1;
+bool uloop_cancelled = false;
+bool uloop_handle_sigchld = true;
+static int uloop_status = 0;
+static bool do_sigchld = false;
- return kflags;
-}
+static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS];
+static int cur_fd, cur_nfds;
+static int uloop_run_depth = 0;
-static int register_poll(struct uloop_fd *fd, unsigned int flags)
-{
- struct timespec timeout = { 0, 0 };
- struct kevent ev[2];
- unsigned int changed;
- int nev = 0;
-
- changed = fd->kqflags ^ flags;
- if (changed & ULOOP_EDGE_TRIGGER)
- changed |= flags;
-
- if (changed & ULOOP_READ) {
- uint16_t kflags = get_flags(flags, ULOOP_READ);
- EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd);
- }
+int uloop_fd_add(struct uloop_fd *sock, unsigned int flags);
- if (changed & ULOOP_WRITE) {
- uint16_t kflags = get_flags(flags, ULOOP_WRITE);
- EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd);
- }
+#ifdef USE_KQUEUE
+#include "uloop-kqueue.c"
+#endif
- if (nev && (kevent(poll_fd, ev, nev, NULL, 0, &timeout) == -1))
- return -1;
+#ifdef USE_EPOLL
+#include "uloop-epoll.c"
+#endif
- fd->kqflags = flags;
- return 0;
+static void waker_consume(struct uloop_fd *fd, unsigned int events)
+{
+ char buf[4];
+
+ while (read(fd->fd, buf, 4) > 0)
+ ;
}
-int uloop_fd_delete(struct uloop_fd *sock)
+static int waker_pipe = -1;
+static struct uloop_fd waker_fd = {
+ .fd = -1,
+ .cb = waker_consume,
+};
+
+static void waker_init_fd(int fd)
{
- sock->registered = false;
- return register_poll(sock, 0);
+ fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
+ fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
}
-static void uloop_run_events(int timeout)
+static int waker_init(void)
{
- struct kevent events[ULOOP_MAX_EVENTS];
- struct timespec ts;
- int nfds, n;
-
- if (timeout > 0) {
- ts.tv_sec = timeout / 1000;
- ts.tv_nsec = timeout * 1000000;
- }
+ int fds[2];
- nfds = kevent(poll_fd, NULL, 0, events, ARRAY_SIZE(events), timeout > 0 ? &ts : NULL);
- for(n = 0; n < nfds; ++n)
- {
- struct uloop_fd *u = events[n].udata;
- unsigned int ev = 0;
+ if (waker_pipe >= 0)
+ return 0;
- if(events[n].flags & EV_ERROR) {
- u->error = true;
- uloop_fd_delete(u);
- }
+ if (pipe(fds) < 0)
+ return -1;
- if(events[n].filter == EVFILT_READ)
- ev |= ULOOP_READ;
- else if (events[n].filter == EVFILT_WRITE)
- ev |= ULOOP_WRITE;
+ waker_init_fd(fds[0]);
+ waker_init_fd(fds[1]);
+ waker_pipe = fds[1];
- if(events[n].flags & EV_EOF)
- u->eof = true;
- else if (!ev)
- continue;
+ waker_fd.fd = fds[0];
+ waker_fd.cb = waker_consume;
+ uloop_fd_add(&waker_fd, ULOOP_READ);
- if(u->cb)
- u->cb(u, ev);
- }
+ return 0;
}
-#endif
-
-#ifdef USE_EPOLL
-
-/**
- * FIXME: uClibc < 0.9.30.3 does not define EPOLLRDHUP for Linux >= 2.6.17
- */
-#ifndef EPOLLRDHUP
-#define EPOLLRDHUP 0x2000
-#endif
+static void uloop_setup_signals(bool add);
int uloop_init(void)
{
- poll_fd = epoll_create(32);
- if (poll_fd < 0)
+ if (uloop_init_pollfd() < 0)
+ return -1;
+
+ if (waker_init() < 0) {
+ uloop_done();
return -1;
+ }
+
+ uloop_setup_signals(true);
- fcntl(poll_fd, F_SETFD, fcntl(poll_fd, F_GETFD) | FD_CLOEXEC);
return 0;
}
-static int register_poll(struct uloop_fd *fd, unsigned int flags)
+static bool uloop_fd_stack_event(struct uloop_fd *fd, int events)
{
- struct epoll_event ev;
- int op = fd->registered ? EPOLL_CTL_MOD : EPOLL_CTL_ADD;
+ struct uloop_fd_stack *cur;
- memset(&ev, 0, sizeof(struct epoll_event));
+ /*
+ * 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;
- if (flags & ULOOP_READ)
- ev.events |= EPOLLIN | EPOLLRDHUP;
-
- if (flags & ULOOP_WRITE)
- ev.events |= EPOLLOUT;
-
- if (flags & ULOOP_EDGE_TRIGGER)
- ev.events |= EPOLLET;
+ for (cur = fd_stack; cur; cur = cur->next) {
+ if (cur->fd != fd)
+ continue;
- ev.data.fd = fd->fd;
- ev.data.ptr = fd;
+ if (events < 0)
+ cur->fd = NULL;
+ else
+ cur->events |= events | ULOOP_EVENT_BUFFERED;
- return epoll_ctl(poll_fd, op, fd->fd, &ev);
-}
+ return true;
+ }
-int uloop_fd_delete(struct uloop_fd *sock)
-{
- sock->registered = false;
- return epoll_ctl(poll_fd, EPOLL_CTL_DEL, sock->fd, 0);
+ return false;
}
static void uloop_run_events(int timeout)
{
- struct epoll_event events[ULOOP_MAX_EVENTS];
- int nfds, n;
+ 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;
+ }
- nfds = epoll_wait(poll_fd, events, ARRAY_SIZE(events), timeout);
- for(n = 0; n < nfds; ++n)
- {
- struct uloop_fd *u = events[n].data.ptr;
- unsigned int ev = 0;
+ while (cur_nfds > 0) {
+ struct uloop_fd_stack stack_cur;
+ unsigned int events;
- if(events[n].events & EPOLLERR) {
- u->error = true;
- uloop_fd_delete(u);
- }
+ cur = &cur_fds[cur_fd++];
+ cur_nfds--;
- if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR)))
+ fd = cur->fd;
+ events = cur->events;
+ if (!fd)
continue;
- if(events[n].events & EPOLLRDHUP)
- u->eof = true;
-
- if(events[n].events & EPOLLIN)
- ev |= ULOOP_READ;
+ if (!fd->cb)
+ continue;
- if(events[n].events & EPOLLOUT)
- ev |= ULOOP_WRITE;
+ if (uloop_fd_stack_event(fd, cur->events))
+ continue;
- if(u->cb)
- u->cb(u, ev);
+ 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;
}
}
-#endif
-
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)
{
- struct uloop_timeout **head = &first_timeout;
- struct uloop_timeout *prev = NULL;
+ struct uloop_timeout *tmp;
+ struct list_head *h = &timeouts;
if (timeout->pending)
return -1;
- while (*head) {
- if (tv_diff(&(*head)->time, &timeout->time) > 0)
+ list_for_each_entry(tmp, &timeouts, list) {
+ if (tv_diff(&tmp->time, &timeout->time) > 0) {
+ h = &tmp->list;
break;
-
- prev = *head;
- head = &(*head)->next;
+ }
}
- timeout->prev = prev;
- timeout->next = *head;
- if (timeout->next)
- timeout->next->prev = timeout;
- *head = timeout;
+ list_add_tail(&timeout->list, h);
timeout->pending = true;
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;
+ time->tv_usec += (msecs % 1000) * 1000;
if (time->tv_usec > 1000000) {
time->tv_sec++;
- time->tv_usec %= 100000;
+ time->tv_usec -= 1000000;
}
return uloop_timeout_add(timeout);
if (!timeout->pending)
return -1;
- if (timeout->prev)
- timeout->prev->next = timeout->next;
- else
- first_timeout = timeout->next;
+ list_del(&timeout->list);
+ timeout->pending = false;
+
+ return 0;
+}
+
+int uloop_timeout_remaining(struct uloop_timeout *timeout)
+{
+ struct timeval now;
+
+ if (!timeout->pending)
+ return -1;
+
+ uloop_gettime(&now);
- if (timeout->next)
- timeout->next->prev = timeout->prev;
+ return tv_diff(&timeout->time, &now);
+}
- timeout->pending = false;
+int uloop_process_add(struct uloop_process *p)
+{
+ struct uloop_process *tmp;
+ struct list_head *h = &processes;
+
+ if (p->pending)
+ return -1;
+
+ list_for_each_entry(tmp, &processes, list) {
+ if (tmp->pid > p->pid) {
+ h = &tmp->list;
+ break;
+ }
+ }
+
+ list_add_tail(&p->list, h);
+ p->pending = true;
+
+ return 0;
+}
+
+int uloop_process_delete(struct uloop_process *p)
+{
+ if (!p->pending)
+ return -1;
+
+ list_del(&p->list);
+ p->pending = false;
return 0;
}
+static void uloop_handle_processes(void)
+{
+ struct uloop_process *p, *tmp;
+ pid_t pid;
+ int ret;
+
+ do_sigchld = false;
+
+ while (1) {
+ pid = waitpid(-1, &ret, WNOHANG);
+ if (pid < 0 && errno == EINTR)
+ continue;
+
+ if (pid <= 0)
+ return;
+
+ list_for_each_entry_safe(p, tmp, &processes, list) {
+ if (p->pid < pid)
+ continue;
+
+ if (p->pid > pid)
+ break;
+
+ uloop_process_delete(p);
+ p->cb(p, ret);
+ }
+ }
+
+}
+
+static void uloop_signal_wake(void)
+{
+ do {
+ if (write(waker_pipe, "w", 1) < 0) {
+ if (errno == EINTR)
+ continue;
+ }
+ break;
+ } while (1);
+}
+
static void uloop_handle_sigint(int signo)
{
+ uloop_status = signo;
uloop_cancelled = true;
+ uloop_signal_wake();
+}
+
+static void uloop_sigchld(int signo)
+{
+ do_sigchld = true;
+ uloop_signal_wake();
+}
+
+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_setup_signals(void)
+static void uloop_ignore_signal(int signum, bool ignore)
{
struct sigaction s;
- memset(&s, 0, sizeof(struct sigaction));
- s.sa_handler = uloop_handle_sigint;
- s.sa_flags = 0;
- sigaction(SIGINT, &s, NULL);
+ void *new_handler = NULL;
+
+ sigaction(signum, NULL, &s);
+
+ 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 (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);
+
+ if (uloop_handle_sigchld)
+ 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;
int diff;
- if (!first_timeout)
+ if (list_empty(&timeouts))
return -1;
- diff = tv_diff(&first_timeout->time, tv);
+ timeout = list_first_entry(&timeouts, struct uloop_timeout, list);
+ diff = tv_diff(&timeout->time, tv);
if (diff < 0)
return 0;
static void uloop_process_timeouts(struct timeval *tv)
{
- struct uloop_timeout *timeout;
+ struct uloop_timeout *t;
+
+ while (!list_empty(&timeouts)) {
+ t = list_first_entry(&timeouts, struct uloop_timeout, list);
- while (first_timeout) {
- if (tv_diff(&first_timeout->time, tv) > 0)
+ if (tv_diff(&t->time, tv) > 0)
break;
- timeout = first_timeout;
- uloop_timeout_cancel(timeout);
- if (timeout->cb)
- timeout->cb(timeout);
+ uloop_timeout_cancel(t);
+ if (t->cb)
+ t->cb(t);
}
}
-void uloop_run(void)
+static void uloop_clear_timeouts(void)
{
+ struct uloop_timeout *t, *tmp;
+
+ list_for_each_entry_safe(t, tmp, &timeouts, list)
+ uloop_timeout_cancel(t);
+}
+
+static void uloop_clear_processes(void)
+{
+ struct uloop_process *p, *tmp;
+
+ list_for_each_entry_safe(p, tmp, &processes, list)
+ uloop_process_delete(p);
+}
+
+bool uloop_cancelling(void)
+{
+ return uloop_run_depth > 0 && uloop_cancelled;
+}
+
+int uloop_run_timeout(int timeout)
+{
+ int next_time = 0;
struct timeval tv;
- uloop_setup_signals();
- while(!uloop_cancelled)
+ uloop_run_depth++;
+
+ uloop_status = 0;
+ uloop_cancelled = false;
+ while (!uloop_cancelled)
{
- gettimeofday(&tv, NULL);
+ uloop_gettime(&tv);
uloop_process_timeouts(&tv);
- uloop_run_events(uloop_get_next_timeout(&tv));
+
+ if (do_sigchld)
+ uloop_handle_processes();
+
+ if (uloop_cancelled)
+ break;
+
+ uloop_gettime(&tv);
+
+ next_time = uloop_get_next_timeout(&tv);
+ if (timeout >= 0 && timeout < next_time)
+ next_time = timeout;
+ uloop_run_events(next_time);
}
+
+ --uloop_run_depth;
+
+ return uloop_status;
}
void uloop_done(void)
{
- close(poll_fd);
+ uloop_setup_signals(false);
+
+ if (poll_fd >= 0) {
+ close(poll_fd);
+ poll_fd = -1;
+ }
+
+ if (waker_pipe >= 0) {
+ uloop_fd_delete(&waker_fd);
+ close(waker_pipe);
+ close(waker_fd.fd);
+ waker_pipe = -1;
+ }
+
+ uloop_clear_timeouts();
+ uloop_clear_processes();
}
projects / project / libubox.git / blobdiff