Thanks. We can improve on that a bit, by using one of the pointers to
indicate whether the storage is allocated, instead of requiring an extra
boolean for this information. I pushed the attached patch.
From c5a83dbb9596c98a260af9b545fc64a57b59be60 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email protected]>
Date: Wed, 23 Apr 2014 23:20:35 -0700
Subject: [PATCH] dfa: fix memory leak reintroduced by previous patch
Reported by Norihiro Tanaka in <http://bugs.gnu.org/17328#16>.
* src/dfa.c (dfaexec): Allocate mb_match_lens and mb_follows only
if not already allocated.
(free_mbdata): Null out mb_match_lens to mark it as being freed.
---
src/dfa.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/src/dfa.c b/src/dfa.c
index 42a9736..5dc0f09 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -426,7 +426,8 @@ struct dfa
position_set mb_follows; /* Follow set added by ANYCHAR and/or MBCSET
on demand. */
int *mb_match_lens; /* Array of length reduced by ANYCHAR and/or
- MBCSET. */
+ MBCSET. Null if mb_follows.elems has not
+ been allocated. */
};
/* Some macros for user access to dfa internals. */
@@ -3245,8 +3246,11 @@ dfaexec (struct dfa *d, char const *begin, char *end,
if (d->mb_cur_max > 1)
{
memset (&d->mbs, 0, sizeof d->mbs);
- d->mb_match_lens = xnmalloc (d->nleaves, sizeof *d->mb_match_lens);
- alloc_position_set (&d->mb_follows, d->nleaves);
+ if (! d->mb_match_lens)
+ {
+ d->mb_match_lens = xnmalloc (d->nleaves, sizeof *d->mb_match_lens);
+ alloc_position_set (&d->mb_follows, d->nleaves);
+ }
}
for (;;)
@@ -3422,6 +3426,7 @@ free_mbdata (struct dfa *d)
free (d->mbcsets);
free (d->mb_follows.elems);
free (d->mb_match_lens);
+ d->mb_match_lens = NULL;
}
/* Initialize the components of a dfa that the other routines don't
--
1.9.0
