From 9a800b5622b0feec879c3f5c81f7af5a8640e57c Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Sat, 14 Dec 2013 05:08:15 +0100 Subject: [PATCH] event: instead of reset the revents field when we get new revents data from epoll, OR it in --- src/libsystemd-bus/sd-event.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/src/libsystemd-bus/sd-event.c b/src/libsystemd-bus/sd-event.c index 94813950b..bf8b0fcf6 100644 --- a/src/libsystemd-bus/sd-event.c +++ b/src/libsystemd-bus/sd-event.c @@ -1569,12 +1569,21 @@ static int event_arm_timer( return 0; } -static int process_io(sd_event *e, sd_event_source *s, uint32_t events) { +static int process_io(sd_event *e, sd_event_source *s, uint32_t revents) { assert(e); assert(s); assert(s->type == SOURCE_IO); - s->io.revents = events; + /* If the event source was already pending, we just OR in the + * new revents, otherwise we reset the value. The ORing is + * necessary to handle EPOLLONESHOT events properly where + * readability might happen independently of writability, and + * we need to keep track of both */ + + if (s->pending) + s->io.revents |= revents; + else + s->io.revents = revents; return source_set_pending(s, true); } -- 2.30.2