rpms
/
systemd
2
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
systemd/0045-sd-event-split-run-int...

245 lines
7.8 KiB
Diff
Raw Blame History

From c45a5a74465a39280b855f9d720b2ab4779a47fa Mon Sep 17 00:00:00 2001
From: Tom Gundersen <teg@jklm.no>
Date: Fri, 15 Aug 2014 18:49:29 +0200
Subject: [PATCH] sd-event: split run into prepare/wait/dispatch
This will allow sd-event to be integrated into an external event loop, which
in turn will allow (say) glib-based applications to use our various libraries,
without manually integrating each of them (bus, rtnl, dhcp, ...).
The external event-loop should integrate sd-event int he following way:
Every iteration must start with a call to sd_event_prepare(), which will
return 0 if no event sources are ready to be processed, a positive value if
they are and a negative value on error. sd_event_prepare() may only be called
following sd_event_dispatch(); a call to sd_event_wait() indicating that no
sources are ready to be dispatched; or a failed call to sd_event_dispatch() or
sd_event_wait().
A successful call to sd_event_prepare() indicating that no event sources are
ready to be dispatched must be followed by a call to sd_event_wait(),
which will return 0 if it timed out without event sources being ready to
be processed, a negative value on error and a positive value otherwise.
sd_event_wait() may only be called following a successful call to
sd_event_prepare() indicating that no event sources are ready to be dispatched.
If sd_event_wait() indicates that some events sources are ready to be
dispatched, it must be followed by a call to sd_event_dispatch(). This
is the only time sd_event_dispatch() may be called.
---
src/libsystemd/sd-event/sd-event.c | 122 +++++++++++++++++++++++++++++--------
src/systemd/sd-event.h | 5 ++
2 files changed, 102 insertions(+), 25 deletions(-)
diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
index e062997a80..a71962c24c 100644
--- a/src/libsystemd/sd-event/sd-event.c
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -2210,12 +2210,8 @@ static int process_watchdog(sd_event *e) {
return arm_watchdog(e);
}
-_public_ int sd_event_run(sd_event *e, uint64_t timeout) {
- struct epoll_event *ev_queue;
- unsigned ev_queue_max;
- sd_event_source *p;
- int r, i, m;
- bool timedout;
+_public_ int sd_event_prepare(sd_event *e) {
+ int r;
assert_return(e, -EINVAL);
assert_return(!event_pid_changed(e), -ECHILD);
@@ -2223,38 +2219,60 @@ _public_ int sd_event_run(sd_event *e, uint64_t timeout) {
assert_return(e->state == SD_EVENT_PASSIVE, -EBUSY);
if (e->exit_requested)
- return dispatch_exit(e);
+ goto pending;
- sd_event_ref(e);
e->iteration++;
- e->state = SD_EVENT_RUNNING;
r = event_prepare(e);
if (r < 0)
- goto finish;
+ return r;
r = event_arm_timer(e, &e->realtime);
if (r < 0)
- goto finish;
+ return r;
r = event_arm_timer(e, &e->boottime);
if (r < 0)
- goto finish;
+ return r;
r = event_arm_timer(e, &e->monotonic);
if (r < 0)
- goto finish;
+ return r;
r = event_arm_timer(e, &e->realtime_alarm);
if (r < 0)
- goto finish;
+ return r;
r = event_arm_timer(e, &e->boottime_alarm);
if (r < 0)
- goto finish;
+ return r;
if (event_next_pending(e) || e->need_process_child)
- timeout = 0;
+ goto pending;
+
+ e->state = SD_EVENT_PREPARED;
+
+ return 0;
+
+pending:
+ e->state = SD_EVENT_PREPARED;
+ return sd_event_wait(e, 0);
+}
+
+_public_ int sd_event_wait(sd_event *e, uint64_t timeout) {
+ struct epoll_event *ev_queue;
+ unsigned ev_queue_max;
+ int r, m, i;
+
+ assert_return(e, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(e->state == SD_EVENT_PREPARED, -EBUSY);
+
+ if (e->exit_requested) {
+ e->state = SD_EVENT_PENDING;
+ return 1;
+ }
ev_queue_max = CLAMP(e->n_sources, 1U, EPOLL_QUEUE_MAX);
ev_queue = newa(struct epoll_event, ev_queue_max);
@@ -2262,12 +2280,16 @@ _public_ int sd_event_run(sd_event *e, uint64_t timeout) {
m = epoll_wait(e->epoll_fd, ev_queue, ev_queue_max,
timeout == (uint64_t) -1 ? -1 : (int) ((timeout + USEC_PER_MSEC - 1) / USEC_PER_MSEC));
if (m < 0) {
- r = errno == EAGAIN || errno == EINTR ? 1 : -errno;
+ if (errno == EINTR) {
+ e->state = SD_EVENT_PENDING;
+ return 1;
+ }
+
+ r = -errno;
+
goto finish;
}
- timedout = m == 0;
-
dual_timestamp_get(&e->timestamp);
e->timestamp_boottime = now(CLOCK_BOOTTIME);
@@ -2324,21 +2346,71 @@ _public_ int sd_event_run(sd_event *e, uint64_t timeout) {
goto finish;
}
- p = event_next_pending(e);
- if (!p) {
- r = !timedout;
- goto finish;
+ if (event_next_pending(e)) {
+ e->state = SD_EVENT_PENDING;
+
+ return 1;
}
- r = source_dispatch(p);
+ r = 0;
finish:
e->state = SD_EVENT_PASSIVE;
- sd_event_unref(e);
return r;
}
+_public_ int sd_event_dispatch(sd_event *e) {
+ sd_event_source *p;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(e->state == SD_EVENT_PENDING, -EBUSY);
+
+ if (e->exit_requested)
+ return dispatch_exit(e);
+
+ p = event_next_pending(e);
+ if (p) {
+ sd_event_ref(e);
+
+ e->state = SD_EVENT_RUNNING;
+ r = source_dispatch(p);
+ e->state = SD_EVENT_PASSIVE;
+
+ sd_event_unref(e);
+
+ return r;
+ }
+
+ e->state = SD_EVENT_PASSIVE;
+
+ return 1;
+}
+
+_public_ int sd_event_run(sd_event *e, uint64_t timeout) {
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(e->state == SD_EVENT_PASSIVE, -EBUSY);
+
+ r = sd_event_prepare(e);
+ if (r > 0)
+ return sd_event_dispatch(e);
+ else if (r < 0)
+ return r;
+
+ r = sd_event_wait(e, timeout);
+ if (r > 0)
+ return sd_event_dispatch(e);
+ else
+ return r;
+}
+
_public_ int sd_event_loop(sd_event *e) {
int r;
diff --git a/src/systemd/sd-event.h b/src/systemd/sd-event.h
index d96852a763..8e013b33f6 100644
--- a/src/systemd/sd-event.h
+++ b/src/systemd/sd-event.h
@@ -52,6 +52,8 @@ enum {
enum {
SD_EVENT_PASSIVE,
+ SD_EVENT_PREPARED,
+ SD_EVENT_PENDING,
SD_EVENT_RUNNING,
SD_EVENT_EXITING,
SD_EVENT_FINISHED
@@ -84,6 +86,9 @@ int sd_event_add_defer(sd_event *e, sd_event_source **s, sd_event_handler_t call
int sd_event_add_post(sd_event *e, sd_event_source **s, sd_event_handler_t callback, void *userdata);
int sd_event_add_exit(sd_event *e, sd_event_source **s, sd_event_handler_t callback, void *userdata);
+int sd_event_prepare(sd_event *e);
+int sd_event_wait(sd_event *e, uint64_t timeout);
+int sd_event_dispatch(sd_event *e);
int sd_event_run(sd_event *e, uint64_t timeout);
int sd_event_loop(sd_event *e);
int sd_event_exit(sd_event *e, int code);
Reference in New Issue View Git Blame Copy Permalink