/*
* uloop - event loop implementation
*
- * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org>
+ * 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
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;
+
#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 int uloop_status = 0;
static bool do_sigchld = false;
static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS];
static int cur_fd, cur_nfds;
+static int uloop_run_depth = 0;
-#ifdef USE_KQUEUE
-
-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;
+int uloop_fd_add(struct uloop_fd *sock, unsigned int flags);
- return kflags;
-}
+#ifdef USE_KQUEUE
+#include "uloop-kqueue.c"
+#endif
-static struct kevent events[ULOOP_MAX_EVENTS];
+#ifdef USE_EPOLL
+#include "uloop-epoll.c"
+#endif
-static int register_kevent(struct uloop_fd *fd, unsigned int flags)
+static void waker_consume(struct uloop_fd *fd, unsigned int events)
{
- 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);
- }
+ char buf[4];
- if (!flags)
- fl |= EV_DELETE;
-
- fd->flags = flags;
- if (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1)
- return -1;
-
- return 0;
+ while (read(fd->fd, buf, 4) > 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 waker_pipe = -1;
+static struct uloop_fd waker_fd = {
+ .fd = -1,
+ .cb = waker_consume,
+};
-static int __uloop_fd_delete(struct uloop_fd *fd)
+static void waker_init_fd(int fd)
{
- return register_poll(fd, 0);
+ fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
+ fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
}
-static int uloop_fetch_events(int timeout)
+static int waker_init(void)
{
- struct timespec ts;
- int nfds, n;
+ int fds[2];
- 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 (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)
- cur->fd = NULL;
+ waker_fd.fd = fds[0];
+ waker_fd.cb = waker_consume;
+ uloop_fd_add(&waker_fd, ULOOP_READ);
- 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;
+ 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)
{
- if (poll_fd >= 0)
- return 0;
-
- poll_fd = epoll_create(32);
- if (poll_fd < 0)
+ if (uloop_init_pollfd() < 0)
return -1;
- 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)
-{
- struct epoll_event ev;
- int op = fd->registered ? EPOLL_CTL_MOD : EPOLL_CTL_ADD;
-
- memset(&ev, 0, sizeof(struct epoll_event));
-
- if (flags & ULOOP_READ)
- ev.events |= EPOLLIN | EPOLLRDHUP;
-
- if (flags & ULOOP_WRITE)
- ev.events |= EPOLLOUT;
-
- if (flags & ULOOP_EDGE_TRIGGER)
- ev.events |= EPOLLET;
-
- ev.data.fd = fd->fd;
- ev.data.ptr = fd;
- fd->flags = flags;
-
- return epoll_ctl(poll_fd, op, fd->fd, &ev);
-}
+ if (waker_init() < 0) {
+ uloop_done();
+ return -1;
+ }
-static struct epoll_event events[ULOOP_MAX_EVENTS];
+ uloop_setup_signals(true);
-static int __uloop_fd_delete(struct uloop_fd *sock)
-{
- sock->flags = 0;
- return epoll_ctl(poll_fd, EPOLL_CTL_DEL, sock->fd, 0);
+ return 0;
}
-static int uloop_fetch_events(int timeout)
+static bool uloop_fd_stack_event(struct uloop_fd *fd, int events)
{
- int n, nfds;
+ struct uloop_fd_stack *cur;
- nfds = epoll_wait(poll_fd, events, ARRAY_SIZE(events), timeout);
- 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;
+ /*
+ * 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;
- cur->fd = u;
- if (!u)
+ for (cur = fd_stack; cur; cur = cur->next) {
+ if (cur->fd != fd)
continue;
- if (events[n].events & (EPOLLERR|EPOLLHUP)) {
- u->error = true;
- uloop_fd_delete(u);
- }
-
- if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP))) {
+ if (events < 0)
cur->fd = NULL;
- continue;
- }
+ else
+ cur->events |= events | ULOOP_EVENT_BUFFERED;
- if(events[n].events & EPOLLRDHUP)
- u->eof = true;
-
- if(events[n].events & EPOLLIN)
- ev |= ULOOP_READ;
-
- if(events[n].events & EPOLLOUT)
- ev |= ULOOP_WRITE;
-
- cur->events = ev;
+ return true;
}
- return nfds;
+ return false;
}
-#endif
-
static void uloop_run_events(int timeout)
{
struct uloop_fd_event *cur;
}
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;
- fd->cb(fd, cur->events);
+ 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;
}
}
sock->registered = true;
sock->eof = false;
+ sock->error = false;
out:
return ret;
{
int i;
- if (!fd->registered)
- return 0;
-
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);
}
if (timeout->pending)
uloop_timeout_cancel(timeout);
- uloop_gettime(&timeout->time);
+ 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);
while (1) {
pid = waitpid(-1, &ret, WNOHANG);
+ if (pid < 0 && errno == EINTR)
+ continue;
+
if (pid <= 0)
return;
}
+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;
+ void *new_handler = NULL;
- memset(&s, 0, sizeof(struct sigaction));
- s.sa_handler = uloop_handle_sigint;
- s.sa_flags = 0;
- sigaction(SIGINT, &s, NULL);
+ sigaction(signum, NULL, &s);
- if (uloop_handle_sigchld) {
- s.sa_handler = uloop_sigchld;
- sigaction(SIGCHLD, &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 (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)
uloop_process_delete(p);
}
-void uloop_run(void)
+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)
{
uloop_gettime(&tv);
uloop_process_timeouts(&tv);
- if (uloop_cancelled)
- break;
if (do_sigchld)
uloop_handle_processes();
- uloop_run_events(uloop_get_next_timeout(&tv));
+
+ 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)
{
- if (poll_fd < 0)
- return;
+ uloop_setup_signals(false);
+
+ if (poll_fd >= 0) {
+ close(poll_fd);
+ poll_fd = -1;
+ }
- 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();