encounter
/
SDL
mirror of https://github.com/encounter/SDL.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Correct handling of sentinel events when polling without removing events 

Fixes https://github.com/libsdl-org/SDL/issues/5350
This commit is contained in:
Sam Lantinga 2022-02-21 11:35:31 -08:00
parent d90bd261f3
commit 6c531c4334
1 changed files with 34 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
src/events/SDL_events.c
View File

@ -660,7 +660,7 @@ static int
SDL_PeepEventsInternal(SDL_Event * events, int numevents, SDL_eventaction action,
Uint32 minType, Uint32 maxType, SDL_bool include_sentinel)
{
int i, used;
int i, used, sentinels_expected = 0;
/* Don't look after we've quit */
if (!SDL_AtomicGet(&SDL_EventQ.active)) {
@ -723,8 +723,15 @@ SDL_PeepEventsInternal(SDL_Event * events, int numevents, SDL_eventaction action
}
if (type == SDL_POLLSENTINEL) {
/* Special handling for the sentinel event */
if (!include_sentinel || SDL_AtomicGet(&SDL_sentinel_pending) > 0) {
/* Skip it, we don't want to include it or there's another one pending */
if (!include_sentinel) {
/* Skip it, we don't want to include it */
continue;
}
if (!events || action != SDL_GETEVENT) {
++sentinels_expected;
}
if (SDL_AtomicGet(&SDL_sentinel_pending) > sentinels_expected) {
/* Skip it, there's another one pending */
continue;
}
}
@ -991,6 +998,7 @@ SDL_WaitEventTimeout(SDL_Event * event, int timeout)
SDL_Window *wakeup_window;
Uint32 start, expiration;
SDL_bool include_sentinel = (timeout == 0) ? SDL_TRUE : SDL_FALSE;
int result;
/* If there isn't a poll sentinel event pending, pump events and add one */
if (SDL_AtomicGet(&SDL_sentinel_pending) == 0) {
@ -998,33 +1006,34 @@ SDL_WaitEventTimeout(SDL_Event * event, int timeout)
}
/* First check for existing events */
switch (SDL_PeepEventsInternal(event, 1, SDL_GETEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT, include_sentinel)) {
case -1:
result = SDL_PeepEventsInternal(event, 1, SDL_GETEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT, include_sentinel);
if (result < 0) {
return 0;
case 0:
}
if (include_sentinel) {
if (event) {
if (event->type == SDL_POLLSENTINEL) {
/* Reached the end of a poll cycle, and not willing to wait */
return 0;
}
} else {
/* Need to peek the next event to check for sentinel */
SDL_Event dummy;
if (SDL_PeepEventsInternal(&dummy, 1, SDL_PEEKEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT, SDL_TRUE) &&
dummy.type == SDL_POLLSENTINEL) {
SDL_PeepEventsInternal(&dummy, 1, SDL_GETEVENT, SDL_POLLSENTINEL, SDL_POLLSENTINEL, SDL_TRUE);
/* Reached the end of a poll cycle, and not willing to wait */
return 0;
}
}
}
if (result == 0) {
if (timeout == 0) {
/* No events available, and not willing to wait */
return 0;
}
break;
default:
if (include_sentinel) {
if (event) {
if (event->type == SDL_POLLSENTINEL) {
/* Reached the end of a poll cycle, and not willing to wait */
return 0;
}
} else {
/* Need to peek the next event to check for sentinel */
SDL_Event dummy;
if (SDL_PeepEventsInternal(&dummy, 1, SDL_PEEKEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT, SDL_TRUE) &&
dummy.type == SDL_POLLSENTINEL) {
/* Reached the end of a poll cycle, and not willing to wait */
return 0;
}
}
}
} else {
/* Has existing events */
return 1;
}