tevent: Fix epoll_mod_event() to cope with modifying a multiplexed fde event.

Signed-off-by: Jeremy Allison <jra@samba.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

diff --git a/lib/tevent/tevent_epoll.c b/lib/tevent/tevent_epoll.c
index 97130db0a7d19459b5645ad7f1e8f39277fbade7..d8c10507011718d8a1b09a60dec51000457fff56 100644 (file)
--- a/lib/tevent/tevent_epoll.c
+++ b/lib/tevent/tevent_epoll.c
@@ -480,23 +480,43 @@ static void epoll_del_event(struct epoll_event_context *epoll_ev, struct tevent_
 */
 static void epoll_mod_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)
 {
+       struct tevent_fd *mpx_fde = NULL;
        struct epoll_event event;
        int ret;
 
        fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
        fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
 
+       if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_MPX) {
+               /*
+                * This is a multiplexed fde, we need to include both
+                * flags in the modified event.
+                */
+               mpx_fde = talloc_get_type_abort(fde->additional_data,
+                                               struct tevent_fd);
+
+               mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
+               mpx_fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
+       }
+
        ZERO_STRUCT(event);
        event.events = epoll_map_flags(fde->flags);
+       if (mpx_fde != NULL) {
+               event.events |= epoll_map_flags(mpx_fde->flags);
+       }
        event.data.ptr = fde;
        ret = epoll_ctl(epoll_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event);
        if (ret != 0 && errno == EBADF) {
                tevent_debug(epoll_ev->ev, TEVENT_DEBUG_ERROR,
                             "EPOLL_CTL_MOD EBADF for "
-                            "fde[%p] fd[%d] - disabling\n",
-                            fde, fde->fd);
+                            "fde[%p] mpx_fde[%p] fd[%d] - disabling\n",
+                            fde, mpx_fde, fde->fd);
                DLIST_REMOVE(epoll_ev->ev->fd_events, fde);
                fde->event_ctx = NULL;
+               if (mpx_fde != NULL) {
+                       DLIST_REMOVE(epoll_ev->ev->fd_events, mpx_fde);
+                       mpx_fde->event_ctx = NULL;
+               }
                return;
        } else if (ret != 0) {
                epoll_panic(epoll_ev, "EPOLL_CTL_MOD failed", false);
@@ -508,6 +528,16 @@ static void epoll_mod_event(struct epoll_event_context *epoll_ev, struct tevent_
        if (fde->flags & TEVENT_FD_READ) {
                fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
        }
+
+       if (mpx_fde == NULL) {
+               return;
+       }
+
+       mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
+       /* only if we want to read we want to tell the event handler about errors */
+       if (mpx_fde->flags & TEVENT_FD_READ) {
+               mpx_fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
+       }
 }
 
 static void epoll_update_event(struct epoll_event_context *epoll_ev, struct tevent_fd *fde)