andreacavalli/xserver-multidpi
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

os: Abandon loop after poll call when array of fds has changed

Browse Source 
If a file descriptor is added or removed from an ospoll callback, then
the arrays containing file descriptor information will have all of
their indices changed, so the loop state is no longer consistent. Just
bail out and let the caller come back around to try again.

Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
This commit is contained in:
Keith Packard 2016-08-13 09:02:15 -07:00
parent 7d6fffb601
commit 67fc5d68f9
1 changed files with 10 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
os/ospoll.c
View File

@ -82,6 +82,7 @@ struct ospoll {
struct ospollfd *osfds;
int num;
int size;
Bool changed;
};
#endif
@ -279,6 +280,7 @@ ospoll_add(struct ospoll *ospoll, int fd,
array_insert(ospoll->fds, ospoll->num, sizeof (ospoll->fds[0]), pos);
array_insert(ospoll->osfds, ospoll->num, sizeof (ospoll->osfds[0]), pos);
ospoll->num++;
ospoll->changed = TRUE;
ospoll->fds[pos].fd = fd;
ospoll->fds[pos].events = 0;
@ -316,6 +318,7 @@ ospoll_remove(struct ospoll *ospoll, int fd)
array_delete(ospoll->fds, ospoll->num, sizeof (ospoll->fds[0]), pos);
array_delete(ospoll->osfds, ospoll->num, sizeof (ospoll->osfds[0]), pos);
ospoll->num--;
ospoll->changed = TRUE;
#endif
}
}
@ -408,6 +411,7 @@ ospoll_wait(struct ospoll *ospoll, int timeout)
#endif
#if POLL
nready = xserver_poll(ospoll->fds, ospoll->num, timeout);
ospoll->changed = FALSE;
if (nready > 0) {
int f;
for (f = 0; f < ospoll->num; f++) {
@ -427,6 +431,12 @@ ospoll_wait(struct ospoll *ospoll, int timeout)
xevents |= X_NOTIFY_ERROR;
ospoll->osfds[f].callback(ospoll->fds[f].fd, xevents,
ospoll->osfds[f].data);
/* Check to see if the arrays have changed, and just go back
* around again
*/
if (ospoll->changed)
break;
}
}
}