* bug#8310: update-game-score -r logic broken with MAX_SCORES
@ 2011-03-21 7:37 Paul Eggert
0 siblings, 0 replies; only message in thread
From: Paul Eggert @ 2011-03-21 7:37 UTC (permalink / raw)
To: 8310
Here's a bug found by gcc -Wstrict-overflow (GCC 4.5.2) this one in
in update-game-score -r. I plan to install the following patch.
update-game-score: fix bug with -r
* update-game-score.c (main): Don't set 'scores' to garbage when
-r is specified and scorecount != MAX_SCORES. This bug was
introduced in the 2002-04-10 change, and was found with gcc
-Wstrict-overflow (GCC 4.5.2, x86-64).
=== modified file 'lib-src/update-game-score.c'
--- lib-src/update-game-score.c 2011-02-21 18:06:25 +0000
+++ lib-src/update-game-score.c 2011-03-21 07:17:22 +0000
@@ -242,13 +242,15 @@
push_score (&scores, &scorecount, newscore, user_id, newdata);
sort_scores (scores, scorecount, reverse);
/* Limit the number of scores. If we're using reverse sorting, then
- we should increment the beginning of the array, to skip over the
- *smallest* scores. Otherwise, we just decrement the number of
- scores, since the smallest will be at the end. */
+ also increment the beginning of the array, to skip over the
+ *smallest* scores. Otherwise, just decrementing the number of
+ scores suffices, since the smallest is at the end. */
if (scorecount > MAX_SCORES)
- scorecount -= (scorecount - MAX_SCORES);
- if (reverse)
- scores += (scorecount - MAX_SCORES);
+ {
+ if (reverse)
+ scores += (scorecount - MAX_SCORES);
+ scorecount = MAX_SCORES;
+ }
if (write_scores (scorefile, scores, scorecount) < 0)
{
unlock_file (scorefile, lockstate);
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2011-03-21 7:37 bug#8310: update-game-score -r logic broken with MAX_SCORES Paul Eggert
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