wakealarmd: move timer event from connection to global state.

Rather than having a separate timer event for each active
connection, we now have a single timer event for all connections.

As we keep a sorted list of connections, this is just as easy to work
with.

And it allows us to re-establish the timer after a suspend/resume.
This is needed as the timer might be made more slack by suspend.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/wakealarmd.c b/wakealarmd.c
index 243ef5e2126204e1907dd954492252e389d294ad..8640fb372b226065db2db4721a8b4f47d6c579cd 100644 (file)
--- a/wakealarmd.c
+++ b/wakealarmd.c
@@ -38,7 +38,6 @@
 
 struct conn {
        struct event    ev;
-       struct event    tev;
        time_t          stamp;  /* When to wake */
        int             active; /* stamp has passed */
        struct conn     *next;  /* sorted by 'stamp' */
@@ -47,6 +46,7 @@ struct conn {
 
 struct state {
        struct event    ev;
+       struct event    tev;
        int             disablefd;
        int             disabled;
        void            *watcher;
@@ -54,6 +54,7 @@ struct state {
        int             active_count;
 };
 
+static void do_timeout(int fd, short ev, void *data);
 static void add_han(struct conn *han)
 {
        struct state *state = han->state;
@@ -67,18 +68,9 @@ static void add_han(struct conn *han)
        han->next = *hanp;
        *hanp = han;
 
-       time(&now);
-       if (now < han->stamp) {
-               tv.tv_sec = han->stamp - now;
-               tv.tv_usec = 0;
-               evtimer_add(&han->tev, &tv);
-               han->active = 0;
-       } else {
-               if (!han->active) {
-                       han->active = 1;
-                       state->active_count++;
-               }
-       }
+       if (event_get_base(&state->tev))
+               evtimer_del(&state->tev);
+       do_timeout(0, 0, (void*)state);
 }
 
 static void del_han(struct conn *han)
@@ -92,6 +84,7 @@ static void del_han(struct conn *han)
        if (*hanp == han) {
                *hanp = han->next;
                if (han->active) {
+                       han->active = 0;
                        state->active_count--;
                        if (state->active_count == 0
                            && state->disabled) {
@@ -105,7 +98,6 @@ static void del_han(struct conn *han)
 static void destroy_han(struct conn *han)
 {
        event_del(&han->ev);
-       event_del(&han->tev);
        free(han);
 }
 
@@ -126,20 +118,29 @@ static void do_read(int fd, short ev, void *data)
        }
        del_han(han);
        han->stamp = atol(buf);
-       add_han(han);
        sprintf(buf, "%lld\n", (long long)han->stamp);
        write(fd, buf, strlen(buf));
+       add_han(han);
 }
 
 static void do_timeout(int fd, short ev, void *data)
 {
-       struct conn *han = data;
+       struct state *state = data;
+       struct conn *han;
+       time_t now = time(0);
 
-       if (!han->active) {
-               han->active = 1;
-               han->state->active_count++;
+       for (han = state->conns; han && han->stamp <= now; han = han->next)
+               if (!han->active) {
+                       han->active = 1;
+                       han->state->active_count++;
+                       write(EVENT_FD(&han->ev), "Now\n", 4);
+               }
+       if (han) {
+               struct timeval tv;
+               tv.tv_sec = han->stamp - now;
+               tv.tv_usec = 0;
+               evtimer_add(&state->tev, &tv);
        }
-       write(EVENT_FD(&han->ev), "Now\n", 4);
 }
 
 static void do_accept(int fd, short ev, void *data)
@@ -162,7 +163,6 @@ static void do_accept(int fd, short ev, void *data)
        han->next = state->conns;
        state->conns = han;
 
-       evtimer_set(&han->tev, do_timeout, han);
        event_set(&han->ev, newfd, EV_READ | EV_PERSIST, do_read, han);
        event_add(&han->ev, NULL);
        write(newfd, "0\n", 2);
@@ -175,6 +175,8 @@ static int do_suspend(void *data)
 
        time(&now);
 
+       if (event_get_base(&state->tev))
+               evtimer_del(&state->tev);
        /* active_count must be zero */
        if (state->conns == NULL)
                return 1;
@@ -199,6 +201,13 @@ static int do_suspend(void *data)
        return 1;
 }
 
+static void do_resume(void *data)
+{
+       struct state *state = data;
+
+       do_timeout(0, 0, (void*)state);
+}
+
 int main(int argc, char *argv[])
 {
        struct state st;
@@ -219,9 +228,10 @@ int main(int argc, char *argv[])
        listen(s, 20);
 
        event_init();
-       st.watcher = suspend_watch(do_suspend, NULL, &st);
+       st.watcher = suspend_watch(do_suspend, do_resume, &st);
        event_set(&st.ev, s, EV_READ | EV_PERSIST, do_accept, &st);
        event_add(&st.ev, NULL);
+       evtimer_set(&st.tev, do_timeout, &st);
 
        event_loop(0);
        exit(0);