Factor the test for \0 in grep patterns into a function. Since commit
9eceddeec6 ("Use kwset in grep", 2011-08-21) any pattern containing a
\0 is considered fixed as regcomp() can't handle it.
This limitation was never documented, and other some regular
expression engines are capable of compiling a pattern containing a
\0. Factoring this out makes a subsequent change which does that
smaller.
See a previous commit in this series ("grep: add tests to fix blind
spots with \0 patterns", 2017-04-21) for further details & rationale.
While I'm at it make the comment conform to the style guide, i.e. add
an opening "/*\n".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
---
grep.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/grep.c b/grep.c
index bf6c2494fd..79eb681c6e 100644
--- a/grep.c
+++ b/grep.c
@@ -321,6 +321,18 @@ static NORETURN void compile_regexp_failed(const struct grep_pat *p,
die("%s'%s': %s", where, p->pattern, error);
}
+static int has_null(const char *s, size_t len)
+{
+ /*
+ * regcomp cannot accept patterns with NULs so when using it
+ * we consider any pattern containing a NUL fixed.
+ */
+ if (memchr(s, 0, len))
+ return 1;
+
+ return 0;
+}
+
#ifdef USE_LIBPCRE
static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
{
@@ -394,12 +406,6 @@ static int is_fixed(const char *s, size_t len)
{
size_t i;
- /* regcomp cannot accept patterns with NULs so we
- * consider any pattern containing a NUL fixed.
- */
- if (memchr(s, 0, len))
- return 1;
-
for (i = 0; i < len; i++) {
if (is_regex_special(s[i]))
return 0;
@@ -451,7 +457,7 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
* simple string match using kws. p->fixed tells us if we
* want to use kws.
*/
- if (opt->fixed || is_fixed(p->pattern, p->patternlen))
+ if (opt->fixed || has_null(p->pattern, p->patternlen) || is_fixed(p->pattern, p->patternlen))
p->fixed = !icase || ascii_only;
else
p->fixed = 0;
--
2.11.0