* SOFTWARE.
*/
+#include <assert.h>
#include <stddef.h>
#include <stdio.h>
#include <errno.h>
/** \cond INTERNAL */
+#define TIMER_REMOVED -2
+
+struct wl_event_loop;
+struct wl_event_source_interface;
+struct wl_event_source_timer;
+
+struct wl_event_source {
+ struct wl_event_source_interface *interface;
+ struct wl_event_loop *loop;
+ struct wl_list link;
+ void *data;
+ int fd;
+};
+
+struct wl_timer_heap {
+ struct wl_event_source base;
+ /* pointers to the user-visible event sources */
+ struct wl_event_source_timer **data;
+ int space, active, count;
+};
+
struct wl_event_loop {
int epoll_fd;
struct wl_list check_list;
struct wl_list destroy_list;
struct wl_signal destroy_signal;
+
+ struct wl_timer_heap timers;
};
struct wl_event_source_interface {
struct epoll_event *ep);
};
-struct wl_event_source {
- struct wl_event_source_interface *interface;
- struct wl_event_loop *loop;
- struct wl_list link;
- void *data;
- int fd;
-};
struct wl_event_source_fd {
struct wl_event_source base;
struct wl_event_source_timer {
struct wl_event_source base;
wl_event_loop_timer_func_t func;
+ struct wl_event_source_timer *next_due;
+ struct timespec deadline;
+ int heap_idx;
};
-/** \endcond */
+static int
+noop_dispatch(struct wl_event_source *source,
+ struct epoll_event *ep) {
+ return 0;
+}
+
+struct wl_event_source_interface timer_heap_source_interface = {
+ noop_dispatch,
+};
+
+static bool
+time_lt(struct timespec ta, struct timespec tb)
+{
+ if (ta.tv_sec != tb.tv_sec) {
+ return ta.tv_sec < tb.tv_sec;
+ }
+ return ta.tv_nsec < tb.tv_nsec;
+}
+
+static int
+set_timer(int timerfd, struct timespec deadline) {
+ struct itimerspec its;
+
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = 0;
+ its.it_value = deadline;
+ return timerfd_settime(timerfd, TFD_TIMER_ABSTIME, &its, NULL);
+}
+
+static int
+clear_timer(int timerfd)
+{
+ struct itimerspec its;
+
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = 0;
+ its.it_value.tv_sec = 0;
+ its.it_value.tv_nsec = 0;
+ return timerfd_settime(timerfd, 0, &its, NULL);
+}
+
+static void
+wl_timer_heap_init(struct wl_timer_heap *timers, struct wl_event_loop *loop)
+{
+ timers->base.fd = -1;
+ timers->base.data = NULL;
+ wl_list_init(&timers->base.link);
+ timers->base.interface = &timer_heap_source_interface;
+ timers->base.loop = loop;
+
+ loop->timers.data = NULL;
+ loop->timers.active = 0;
+ loop->timers.space = 0;
+ loop->timers.count = 0;
+}
+
+static void
+wl_timer_heap_release(struct wl_timer_heap *timers)
+{
+ if (timers->base.fd != -1) {
+ close(timers->base.fd);
+ }
+ free(timers->data);
+}
+
+static int
+wl_timer_heap_ensure_timerfd(struct wl_timer_heap *timers)
+{
+ struct epoll_event ep;
+ int timer_fd;
+
+ if (timers->base.fd != -1)
+ return 0;
+
+ memset(&ep, 0, sizeof ep);
+ ep.events = EPOLLIN;
+ ep.data.ptr = timers;
+
+ timer_fd = timerfd_create(CLOCK_MONOTONIC,
+ TFD_CLOEXEC | TFD_NONBLOCK);
+ if (timer_fd < 0)
+ return -1;
+
+ if (epoll_ctl(timers->base.loop->epoll_fd,
+ EPOLL_CTL_ADD, timer_fd, &ep) < 0) {
+ close(timer_fd);
+ return -1;
+ }
+
+ timers->base.fd = timer_fd;
+ return 0;
+}
+
+static int
+wl_timer_heap_reserve(struct wl_timer_heap *timers)
+{
+ struct wl_event_source_timer **n;
+ int new_space;
+
+ if (timers->count + 1 > timers->space) {
+ new_space = timers->space >= 8 ? timers->space * 2 : 8;
+ n = realloc(timers->data, (size_t)new_space * sizeof(*n));
+ if (!n) {
+ wl_log("Allocation failure when expanding timer list");
+ return -1;
+ }
+ timers->data = n;
+ timers->space = new_space;
+ }
+
+ timers->count++;
+ return 0;
+}
+
+static void
+wl_timer_heap_unreserve(struct wl_timer_heap *timers)
+{
+ struct wl_event_source_timer **n;
+
+ timers->count--;
+
+ if (timers->space >= 16 && timers->space >= 4 * timers->count) {
+ n = realloc(timers->data, (size_t)timers->space / 2 * sizeof(*n));
+ if (!n) {
+ wl_log("Reallocation failure when shrinking timer list");
+ return;
+ }
+ timers->data = n;
+ timers->space = timers->space / 2;
+ }
+}
+
+static int
+heap_set(struct wl_event_source_timer **data,
+ struct wl_event_source_timer *a,
+ int idx)
+{
+ int tmp;
+
+ tmp = a->heap_idx;
+ a->heap_idx = idx;
+ data[a->heap_idx] = a;
+
+ return tmp;
+}
+
+static void
+heap_sift_down(struct wl_event_source_timer **data,
+ int num_active,
+ struct wl_event_source_timer *source)
+{
+ struct wl_event_source_timer *child, *other_child;
+ int cursor_idx;
+ struct timespec key;
+
+ cursor_idx = source->heap_idx;
+ key = source->deadline;
+ while (1) {
+ int lchild_idx = cursor_idx * 2 + 1;
+
+ if (lchild_idx >= num_active) {
+ break;
+ }
+
+ child = data[lchild_idx];
+ if (lchild_idx + 1 < num_active) {
+ other_child = data[lchild_idx + 1];
+ if (time_lt(other_child->deadline, child->deadline))
+ child = other_child;
+ }
+
+ if (time_lt(child->deadline, key))
+ cursor_idx = heap_set(data, child, cursor_idx);
+ else
+ break;
+ }
+
+ heap_set(data, source, cursor_idx);
+}
+
+static void
+heap_sift_up(struct wl_event_source_timer **data,
+ struct wl_event_source_timer *source)
+{
+ int cursor_idx;
+ struct timespec key;
+
+ cursor_idx = source->heap_idx;
+ key = source->deadline;
+ while (cursor_idx > 0) {
+ struct wl_event_source_timer *parent =
+ data[(cursor_idx - 1) / 2];
+
+ if (time_lt(key, parent->deadline))
+ cursor_idx = heap_set(data, parent, cursor_idx);
+ else
+ break;
+ }
+ heap_set(data, source, cursor_idx);
+}
+
+/* requires timer be armed */
+static void
+wl_timer_heap_disarm(struct wl_timer_heap *timers,
+ struct wl_event_source_timer *source)
+{
+ struct wl_event_source_timer *last_end_evt;
+ int old_source_idx;
+
+ assert(source->heap_idx >= 0);
+
+ old_source_idx = source->heap_idx;
+ source->heap_idx = -1;
+ source->deadline.tv_sec = 0;
+ source->deadline.tv_nsec = 0;
+
+ last_end_evt = timers->data[timers->active - 1];
+ timers->data[timers->active - 1] = NULL;
+ timers->active--;
+
+ if (old_source_idx == timers->active)
+ return;
+
+ timers->data[old_source_idx] = last_end_evt;
+ last_end_evt->heap_idx = old_source_idx;
+
+ /* Move the displaced (active) element to its proper place.
+ * Only one of sift-down and sift-up will have any effect */
+ heap_sift_down(timers->data, timers->active, last_end_evt);
+ heap_sift_up(timers->data, last_end_evt);
+}
+
+/* requires timer be disarmed */
+static void
+wl_timer_heap_arm(struct wl_timer_heap *timers,
+ struct wl_event_source_timer *source,
+ struct timespec deadline)
+{
+ assert(source->heap_idx == -1);
+
+ source->deadline = deadline;
+ timers->data[timers->active] = source;
+ source->heap_idx = timers->active;
+ timers->active++;
+ heap_sift_up(timers->data, source);
+}
+
+
+static int
+wl_timer_heap_dispatch(struct wl_timer_heap *timers)
+{
+ struct timespec now;
+ struct wl_event_source_timer *root;
+ struct wl_event_source_timer *list_cursor = NULL, *list_tail = NULL;
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ while (timers->active > 0) {
+ root = timers->data[0];
+ if (time_lt(now, root->deadline))
+ break;
+
+ wl_timer_heap_disarm(timers, root);
+
+ if (list_cursor == NULL)
+ list_cursor = root;
+ else
+ list_tail->next_due = root;
+ list_tail = root;
+ }
+ if (list_tail)
+ list_tail->next_due = NULL;
+
+ if (timers->active > 0) {
+ if (set_timer(timers->base.fd, timers->data[0]->deadline) < 0)
+ return -1;
+ } else {
+ if (clear_timer(timers->base.fd) < 0)
+ return -1;
+ }
+
+ /* Execute precisely the functions for events before `now`, in order.
+ * Because wl_event_loop_dispatch ignores return codes, do the same
+ * here as well */
+ for (; list_cursor; list_cursor = list_cursor->next_due) {
+ if (list_cursor->base.fd != TIMER_REMOVED)
+ list_cursor->func(list_cursor->base.data);
+ }
+
+ return 0;
+}
static int
wl_event_source_timer_dispatch(struct wl_event_source *source,
struct epoll_event *ep)
{
- struct wl_event_source_timer *timer_source =
- (struct wl_event_source_timer *) source;
- uint64_t expires;
- int len;
-
- len = read(source->fd, &expires, sizeof expires);
- if (!(len == -1 && errno == EAGAIN) && len != sizeof expires)
- /* Is there anything we can do here? Will this ever happen? */
- wl_log("timerfd read error: %s\n", strerror(errno));
+ struct wl_event_source_timer *timer;
- return timer_source->func(timer_source->base.data);
+ timer = wl_container_of(source, timer, base);
+ return timer->func(timer->base.data);
}
struct wl_event_source_interface timer_source_interface = {
wl_event_source_timer_dispatch,
};
+/** \endcond */
+
/** Create a timer event source
*
* \param loop The event loop that will process the new source.
{
struct wl_event_source_timer *source;
+ if (wl_timer_heap_ensure_timerfd(&loop->timers) < 0)
+ return NULL;
+
source = malloc(sizeof *source);
if (source == NULL)
return NULL;
source->base.interface = &timer_source_interface;
- source->base.fd = timerfd_create(CLOCK_MONOTONIC,
- TFD_CLOEXEC | TFD_NONBLOCK);
+ source->base.fd = -1;
source->func = func;
+ source->base.loop = loop;
+ source->base.data = data;
+ wl_list_init(&source->base.link);
+ source->next_due = NULL;
+ source->deadline.tv_sec = 0;
+ source->deadline.tv_nsec = 0;
+ source->heap_idx = -1;
- return add_source(loop, &source->base, WL_EVENT_READABLE, data);
+ if (wl_timer_heap_reserve(&loop->timers) < 0) {
+ free(source);
+ return NULL;
+ }
+
+ return &source->base;
}
/** Arm or disarm a timer
WL_EXPORT int
wl_event_source_timer_update(struct wl_event_source *source, int ms_delay)
{
- struct itimerspec its;
+ struct wl_event_source_timer *tsource =
+ wl_container_of(source, tsource, base);
+ struct wl_timer_heap *timers = &tsource->base.loop->timers;
- its.it_interval.tv_sec = 0;
- its.it_interval.tv_nsec = 0;
- its.it_value.tv_sec = ms_delay / 1000;
- its.it_value.tv_nsec = (ms_delay % 1000) * 1000 * 1000;
- if (timerfd_settime(source->fd, 0, &its, NULL) < 0)
- return -1;
+ if (ms_delay > 0) {
+ struct timespec deadline;
+
+ clock_gettime(CLOCK_MONOTONIC, &deadline);
+
+ deadline.tv_nsec += (ms_delay % 1000) * 1000000L;
+ deadline.tv_sec += ms_delay / 1000;
+ if (deadline.tv_nsec >= 1000000000L) {
+ deadline.tv_nsec -= 1000000000L;
+ deadline.tv_sec += 1;
+ }
+
+ if (tsource->heap_idx == -1) {
+ wl_timer_heap_arm(timers, tsource, deadline);
+ } else if (time_lt(deadline, tsource->deadline)) {
+ tsource->deadline = deadline;
+ heap_sift_up(timers->data, tsource);
+ } else {
+ tsource->deadline = deadline;
+ heap_sift_down(timers->data, timers->active, tsource);
+ }
+
+ if (tsource->heap_idx == 0) {
+ /* Only update the timerfd if the new deadline is
+ * the earliest */
+ if (set_timer(timers->base.fd, deadline) < 0)
+ return -1;
+ }
+ } else {
+ if (tsource->heap_idx == -1)
+ return 0;
+ wl_timer_heap_disarm(timers, tsource);
+
+ if (timers->active == 0) {
+ /* Only update the timerfd if this was the last
+ * active timer */
+ if (clear_timer(timers->base.fd) < 0)
+ return -1;
+ }
+ }
return 0;
}
source->fd = -1;
}
+ if (source->interface == &timer_source_interface &&
+ source->fd != TIMER_REMOVED) {
+ /* Disarm the timer (and the loop's timerfd, if necessary),
+ * before removing its space in the loop timer heap */
+ wl_event_source_timer_update(source, 0);
+ wl_timer_heap_unreserve(&loop->timers);
+ /* Set the fd field to to indicate that the timer should NOT
+ * be dispatched in `wl_event_loop_dispatch` */
+ source->fd = TIMER_REMOVED;
+ }
+
wl_list_remove(&source->link);
wl_list_insert(&loop->destroy_list, &source->link);
wl_signal_init(&loop->destroy_signal);
+ wl_timer_heap_init(&loop->timers, loop);
+
return loop;
}
wl_signal_emit(&loop->destroy_signal, loop);
wl_event_loop_process_destroy_list(loop);
+ wl_timer_heap_release(&loop->timers);
close(loop->epoll_fd);
free(loop);
}
*
* \param loop The event loop whose sources to wait for.
* \param timeout The polling timeout in milliseconds.
- * \return 0 for success, -1 for polling error.
+ * \return 0 for success, -1 for polling (or timer update) error.
*
* All the associated event sources are polled. This function blocks until
* any event source delivers an event (idle sources excluded), or the timeout
struct epoll_event ep[32];
struct wl_event_source *source;
int i, count;
+ bool has_timers = false;
wl_event_loop_dispatch_idle(loop);
for (i = 0; i < count; i++) {
source = ep[i].data.ptr;
+ if (source == &loop->timers.base)
+ has_timers = true;
+ }
+
+ if (has_timers) {
+ /* Dispatch timer sources before non-timer sources, so that
+ * the non-timer sources can not cancel (by calling
+ * `wl_event_source_timer_update`) the dispatching of the timers
+ * (Note that timer sources also can't cancel pending non-timer
+ * sources, since epoll_wait has already been called) */
+ if (wl_timer_heap_dispatch(&loop->timers) < 0)
+ return -1;
+ }
+
+ for (i = 0; i < count; i++) {
+ source = ep[i].data.ptr;
if (source->fd != -1)
source->interface->dispatch(source, &ep[i]);
}
projects / platform / upstream / wayland.git / commitdiff