ref: 8ebe3f680e9f343a13bfcaaa2e17745b701ec0c8
parent: d1be5e163c98c99b3b610dc5f4715455d506ba22
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Thu Jan 2 20:40:17 EST 2014
alarm: skip timed out alarms when inserting in procalarm() (thanks erik)
from erik quanstros 9fans post:
i think the list insertion code needs a single-read
test that f->alarm != 0. to prevent the 0 from
acting like a fencepost. e.g. trying to insert -10 into
list -40 -30 0 -20.
if(alarms.head) {
l = &alarms.head;
for(f = *l; f; f = f->palarm) {
>> fw = f->alarm;
>> if(fw != 0 && (long)(fw - when) >= 0) {
up->palarm = f;
*l = up;
goto done;
}
l = &f->palarm;
}
*l = up;
}
--- a/sys/src/9/port/alarm.c
+++ b/sys/src/9/port/alarm.c
@@ -88,7 +88,8 @@
if(alarms.head) {l = &alarms.head;
for(f = *l; f; f = f->palarm) {- if((long)(f->alarm - when) >= 0) {+ time = f->alarm;
+ if(time != 0 && (long)(time - when) >= 0) {up->palarm = f;
*l = up;
goto done;
--
⑨