diff options
| -rw-r--r-- | src/xcb.h | 16 | ||||
| -rw-r--r-- | src/xcb_in.c | 14 |
2 files changed, 28 insertions, 2 deletions
@@ -272,6 +272,22 @@ xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c); xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c); /** + * @brief Returns the next event without reading from the connection. + * @param c: The connection to the X server. + * @return The next already queued event from the server. + * + * This is a version of xcb_poll_for_event that only examines the + * event queue for new events. The function doesn't try to read new + * events from the connection if no queued events are found. + * + * This function is useful for callers that know in advance that all + * interesting events have already been read from the connection. For + * example, callers might use xcb_wait_for_reply and be interested + * only of events that preceded a specific reply. + */ +xcb_generic_event_t *xcb_poll_for_queued_event(xcb_connection_t *c); + +/** * @brief Returns the next event or error that precedes the given request. * @param c: The connection to the X server. * @param request: The limiting sequence number. diff --git a/src/xcb_in.c b/src/xcb_in.c index 501e719..6107065 100644 --- a/src/xcb_in.c +++ b/src/xcb_in.c @@ -535,7 +535,7 @@ xcb_generic_event_t *xcb_wait_for_event(xcb_connection_t *c) return ret; } -xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c) +static xcb_generic_event_t *poll_for_next_event(xcb_connection_t *c, int queued) { xcb_generic_event_t *ret = 0; if(!c->has_error) @@ -543,13 +543,23 @@ xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c) pthread_mutex_lock(&c->iolock); /* FIXME: follow X meets Z architecture changes. */ ret = get_event(c); - if(!ret && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ + if(!ret && !queued && _xcb_in_read(c)) /* _xcb_in_read shuts down the connection on error */ ret = get_event(c); pthread_mutex_unlock(&c->iolock); } return ret; } +xcb_generic_event_t *xcb_poll_for_event(xcb_connection_t *c) +{ + return poll_for_next_event(c, 0); +} + +xcb_generic_event_t *xcb_poll_for_queued_event(xcb_connection_t *c) +{ + return poll_for_next_event(c, 1); +} + static xcb_generic_event_t *get_event_until(xcb_connection_t *c, uint64_t request) { if(c->in.events && XCB_SEQUENCE_COMPARE(c->in.events->sequence, <=, request)) |