Re: [PATCH v4 2/2] grep/pcre2: better support invalid UTF-8 haystacks

On Sun, Jan 24 2021, Ramsay Jones wrote:

On 24/01/2021 13:53, Ramsay Jones wrote:
[snip]

quoted

quoted

diff --git a/grep.c b/grep.c
index efeb6dc58d..e329f19877 100644
--- a/grep.c
+++ b/grep.c

@@ -492,7 +492,13 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 	}
 	if (!opt->ignore_locale && is_utf8_locale() && has_non_ascii(p->pattern) &&
 	    !(!opt->ignore_case && (p->fixed || p->is_fixed)))
-		options |= PCRE2_UTF;
+		options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF);
+
+	if (PCRE2_MATCH_INVALID_UTF &&
+	    options & (PCRE2_UTF | PCRE2_CASELESS) &&
+	    !(PCRE2_MAJOR >= 10 && PCRE2_MAJOR >= 36))

                                   ^^^^^^^^^^^^^^^^^^
I assume that this should be s/_MAJOR/_MINOR/. ;-)

Oops on the s/MAJOR/MINOR/g. Well spotted, I think I'll wait a bit more
for other comments for a re-roll.

Perhaps Junio can be kind and do the s/_MAJOR/_MINOR/ fixup in the
meantime to save be from spamming the list too much...

FWIW I have tested this on a verion without PCRE2_MATCH_INVALID_UTF, but
I think I did that by manually editing the "PCRE2_UTF" line above, and
then wrote this bug.

Although, perhaps you want:

            !(((PCRE2_MAJOR * 100) + PCRE2_MINOR) >= 1036)

... or something similar.

Probably better to use pcre2_config(PCRE2_CONFIG_VERSION) at that point
and versioncmp() the string.

FWIW we used this pattern (I added) before with PCRE, see e87de7cab4
(grep: un-break building with PCRE < 8.32, 2017-05-25).

And if you want to be clever ((PCRE2_MAJOR) | ((PCRE2_MINOR) << 16)) is
probably better, then you can get it out with bit operations :)