libevent: split event_list

Rather than keeping poll events on the same list as events handled by
libevent, split the list in two.
This means we don't need POLL_FD to identify the poll events.
That, combined with the use of event_get_fd() means we don't need to
store the fd in the event struct.  Just the 'num' is sufficient.

Signed-off-by: NeilBrown <neil@brown.name>

diff --git a/lib-libevent.c b/lib-libevent.c
index ef5de4527be20e17f7768fde899522517cee169f..e8b2912137d77de5eac0bc4409e9eb15e37d01c9 100644 (file)
--- a/lib-libevent.c
+++ b/lib-libevent.c
@@ -25,9 +25,15 @@
 static struct map *libevent_map;
 DEF_LOOKUP_CMD(libevent_handle, libevent_map);
 
+enum {
+       EV_LIST,        /* Events handled by libevent */
+       POLL_LIST,      /* Events to poll before calling event_base_loop */
+       NR_LISTS
+};
+
 struct event_info {
        struct event_base *base;
-       struct list_head event_list;
+       struct list_head event_list[NR_LISTS];
        struct pane *home safe;
        int dont_block;
        int deactivated;
@@ -35,17 +41,14 @@ struct event_info {
                free, refresh, noblock;
 };
 
-/* A 'poll' event has fd of -2 */
-#define POLL_FD (-2)
 struct evt {
-       struct event *l safe;
+       struct event *l;
        struct pane *home safe;
        char *event safe;
        struct command *comm safe;
        struct list_head lst;
        int active;     /* Don't delete or free this event, it is running */
        int num;        /* signal or mseconds or fd */
-       int fd;
 };
 
 static void call_event(int thing, short sev, void *evv)
@@ -107,9 +110,11 @@ DEF_CB(libevent_read)
         * Presumably call_event() is now running and will clean up
         * soon.
         */
-       list_for_each_entry(ev, &ei->event_list, lst)
-               if (ci->num >= 0 && ev->fd == ci->num)
+       list_for_each_entry(ev, &ei->event_list[EV_LIST], lst) {
+               int fd = event_get_fd(ev->l);
+               if (fd >= 0 && ci->num >= 0 && fd == ci->num)
                        event_del(ev->l);
+       }
 
        ev = malloc(sizeof(*ev));
 
@@ -120,12 +125,11 @@ DEF_CB(libevent_read)
                                    call_event, ev);
        ev->home = ci->focus;
        ev->comm = command_get(ci->comm2);
-       ev->fd = ci->num;
        ev->num = ci->num;
        ev->active = 0;
        ev->event = "event:read";
        pane_add_notify(ei->home, ev->home, "Notify:Close");
-       list_add(&ev->lst, &ei->event_list);
+       list_add(&ev->lst, &ei->event_list[EV_LIST]);
        event_add(ev->l, NULL);
        return 1;
 }
@@ -143,11 +147,11 @@ DEF_CB(libevent_write)
         * Presumably call_event() is now running and will clean up
         * soon.
         */
-       list_for_each_entry(ev, &ei->event_list, lst)
-               if (ci->num >= 0 && ev->fd == ci->num) {
+       list_for_each_entry(ev, &ei->event_list[EV_LIST], lst) {
+               int fd = event_get_fd(ev->l);
+               if (fd >= 0 && ci->num >= 0 && fd == ci->num)
                        event_del(ev->l);
-                       ev->fd = -1;
-               }
+       }
 
        ev = malloc(sizeof(*ev));
 
@@ -158,12 +162,11 @@ DEF_CB(libevent_write)
                                    call_event, ev);
        ev->home = ci->focus;
        ev->comm = command_get(ci->comm2);
-       ev->fd = ci->num;
        ev->num = ci->num;
        ev->active = 0;
        ev->event = "event:write";
        pane_add_notify(ei->home, ev->home, "Notify:Close");
-       list_add(&ev->lst, &ei->event_list);
+       list_add(&ev->lst, &ei->event_list[EV_LIST]);
        event_add(ev->l, NULL);
        return 1;
 }
@@ -185,12 +188,11 @@ DEF_CB(libevent_signal)
                                    call_event, ev);
        ev->home = ci->focus;
        ev->comm = command_get(ci->comm2);
-       ev->fd = -1;
        ev->num = ci->num;
        ev->active = 0;
        ev->event = "event:signal";
        pane_add_notify(ei->home, ev->home, "Notify:Close");
-       list_add(&ev->lst, &ei->event_list);
+       list_add(&ev->lst, &ei->event_list[EV_LIST]);
        event_add(ev->l, NULL);
        return 1;
 }
@@ -213,12 +215,11 @@ DEF_CB(libevent_timer)
                                    call_timeout_event, ev);
        ev->home = ci->focus;
        ev->comm = command_get(ci->comm2);
-       ev->fd = -1;
        ev->num = ci->num;
        ev->active = 0;
        ev->event = "event:timer";
        pane_add_notify(ei->home, ev->home, "Notify:Close");
-       list_add(&ev->lst, &ei->event_list);
+       list_add(&ev->lst, &ei->event_list[EV_LIST]);
        tv.tv_sec = ev->num / 1000;
        tv.tv_usec = (ev->num % 1000) * 1000;
        event_add(ev->l, &tv);
@@ -238,14 +239,12 @@ DEF_CB(libevent_poll)
        if (!ei->base)
                ei->base = event_base_new();
 
-       ev->l = safe_cast NULL;
        ev->home = ci->focus;
        ev->comm = command_get(ci->comm2);
-       ev->fd = POLL_FD;
        ev->active = 0;
        ev->event = "event:poll";
        pane_add_notify(ei->home, ev->home, "Notify:Close");
-       list_add(&ev->lst, &ei->event_list);
+       list_add(&ev->lst, &ei->event_list[POLL_LIST]);
        return 1;
 }
 
@@ -255,6 +254,7 @@ DEF_CB(libevent_run)
        struct event_base *b = ei->base;
        int dont_block = ei->dont_block;
        struct evt *ev;
+       int i;
 
        ei->dont_block = 0;
 
@@ -268,38 +268,39 @@ DEF_CB(libevent_run)
        }
 
        /* First run any 'poll' events */
-       list_for_each_entry(ev, &ei->event_list, lst)
-               if (ev->fd == POLL_FD) {
-                       ev->active = 1;
-                       if (comm_call(ev->comm, "callback:poll", ev->home,
-                                     POLL_FD) >= 1)
-                               dont_block = True;
-                       if (ev->active == 2) {
-                               list_del(&ev->lst);
-                               command_put(ev->comm);
-                               free(ev);
-                               break;
-                       } else
-                               ev->active = 0;
-                       if (dont_block)
-                               /* Other things might have been removed from list */
-                               break;
-               }
+       list_for_each_entry(ev, &ei->event_list[POLL_LIST], lst) {
+               ev->active = 1;
+               if (comm_call(ev->comm, "callback:poll", ev->home,
+                             -1) >= 1)
+                       dont_block = True;
+               if (ev->active == 2) {
+                       list_del(&ev->lst);
+                       command_put(ev->comm);
+                       free(ev);
+                       break;
+               } else
+                       ev->active = 0;
+               if (dont_block)
+                       /* Other things might have been removed from list */
+                       break;
+       }
 
        /* Disable any alarm set by python (or other interpreter) */
        alarm(0);
        event_base_loop(b, EVLOOP_ONCE | (dont_block ? EVLOOP_NONBLOCK : 0));
        if (ei->base == b)
                return 1;
-       while (!list_empty(&ei->event_list)) {
-               ev = list_first_entry(&ei->event_list, struct evt, lst);
-               list_del(&ev->lst);
-               if (ev->fd != POLL_FD) {
-                       event_del(ev->l);
-                       event_free(ev->l);
+       for (i = 0 ; i < NR_LISTS; i++) {
+               while (!list_empty(&ei->event_list[i])) {
+                       ev = list_first_entry(&ei->event_list[i], struct evt, lst);
+                       list_del(&ev->lst);
+                       if (i == EV_LIST) {
+                               event_del(ev->l);
+                               event_free(ev->l);
+                       }
+                       command_put(ev->comm);
+                       free(ev);
                }
-               command_put(ev->comm);
-               free(ev);
        }
        event_base_free(b);
        return Efail;
@@ -321,22 +322,25 @@ DEF_CB(libevent_free)
        struct evt *ev;
        struct list_head *tmp;
        struct event_info *ei = container_of(ci->comm, struct event_info, free);
-
-       list_for_each_entry_safe(ev, tmp, &ei->event_list, lst)
-               if (ev->home == ci->focus &&
-                   (ci->comm2 == NULL || ev->comm == ci->comm2)) {
-                       list_del_init(&ev->lst);
-                       if (ev->active)
-                               ev->active = 2;
-                       else {
-                               if (ev->fd != POLL_FD) {
-                                       event_del(ev->l);
-                                       event_free(ev->l);
+       int i;
+
+       for (i = 0; i < NR_LISTS; i++) {
+               list_for_each_entry_safe(ev, tmp, &ei->event_list[i], lst)
+                       if (ev->home == ci->focus &&
+                           (ci->comm2 == NULL || ev->comm == ci->comm2)) {
+                               list_del_init(&ev->lst);
+                               if (ev->active)
+                                       ev->active = 2;
+                               else {
+                                       if (i == EV_LIST) {
+                                               event_del(ev->l);
+                                               event_free(ev->l);
+                                       }
+                                       command_put(ev->comm);
+                                       free(ev);
                                }
-                               command_put(ev->comm);
-                               free(ev);
                        }
-               }
+       }
        return 1;
 }
 
@@ -346,18 +350,21 @@ DEF_CB(libevent_refresh)
        struct list_head *tmp;
        struct event_info *ei = container_of(ci->comm, struct event_info, refresh);
        struct list_head old;
-
-       list_add(&old, &ei->event_list);
-       list_del_init(&ei->event_list);
-       list_for_each_entry_safe(ev, tmp, &old, lst) {
-               if (ev->fd != POLL_FD) {
-                       event_del(ev->l);
-                       event_free(ev->l);
+       int i;
+
+       for (i = 0; i < NR_LISTS; i++) {
+               list_add(&old, &ei->event_list[i]);
+               list_del_init(&ei->event_list[i]);
+               list_for_each_entry_safe(ev, tmp, &old, lst) {
+                       if (i == EV_LIST) {
+                               event_del(ev->l);
+                               event_free(ev->l);
+                       }
+                       list_del(&ev->lst);
+                       call_comm(ev->event, ev->home, ev->comm, ev->num);
+                       command_put(ev->comm);
+                       free(ev);
                }
-               list_del(&ev->lst);
-               call_comm(ev->event, ev->home, ev->comm, ev->num);
-               command_put(ev->comm);
-               free(ev);
        }
        return Efallthrough;
 }
@@ -383,9 +390,11 @@ DEF_CMD(libevent_activate)
 {
        struct event_info *ei;
        struct pane *p;
+       int i;
 
        alloc(ei, pane);
-       INIT_LIST_HEAD(&ei->event_list);
+       for (i = 0; i < NR_LISTS; i++)
+               INIT_LIST_HEAD(&ei->event_list[i]);
        ei->read = libevent_read;
        ei->write = libevent_write;
        ei->signal = libevent_signal;