Thanks, I installed that, along with the attached patch which improves
it slightly by avoiding a test of the returned value of memrchr in a
context where memrchr cannot return NULL, plus I redid the while-control
to make it a bit clearer when the loop terminates.
From ad6ca9bb54ae2a9811c889c990ea67d67919a4f4 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email protected]>
Date: Fri, 9 May 2014 14:48:47 -0700
Subject: [PATCH] grep: minor improvements to retry-DFA-superset patch
* src/dfasearch.c (EGexecute): Avoid unnecessary test in a context
where memrchr cannot return a null pointer.
---
src/dfasearch.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/src/dfasearch.c b/src/dfasearch.c
index 9fb7449..77b4e3e 100644
--- a/src/dfasearch.c
+++ b/src/dfasearch.c
@@ -284,23 +284,18 @@ EGexecute (char const *buf, size_t size, size_t
*match_size,
/* Try matching with the superset of DFA, if it's defined. */
if (superset && !exact_kwset_match)
{
- while (true)
+ /* Keep using the superset while it reports multiline
+ potential matches; this is more likely to be fast
+ than falling back to KWset would be. */
+ while ((next_beg = dfaexec (superset, dfa_beg, (char *) end, 1,
+ &count, NULL))
+ && next_beg != end
+ && count != 0)
{
- next_beg = dfaexec (superset, dfa_beg, (char *) end, 1,
- &count, NULL);
- /* If there's no match, or if we've matched the sentinel,
- we're done. */
- if (next_beg == NULL || next_beg == end)
- break;
-
- if (count == 0)
- break;
+ /* Try to match in just one line. */
count = 0;
-
- /* If dfaexec may match in multiple lines, try to
- match in one line. */
beg = memrchr (buf, eol, next_beg - buf);
- beg = beg ? beg + 1 : buf;
+ beg++;
dfa_beg = beg;
}
if (next_beg == NULL || next_beg == end)
@@ -310,6 +305,7 @@ EGexecute (char const *buf, size_t size, size_t *match_size,
end = memchr (next_beg, eol, buflim - next_beg);
end = end ? end + 1 : buflim;
}
+
/* Try matching with DFA. */
next_beg = dfaexec (dfa, dfa_beg, (char *) end, 0, &count, &backref);
--
1.9.0
