[PATCH 3/3] grep: avoid leak of chartables in PCRE2

["Carlo Marcelo Arenas Belón" <carenas@gmail.com>]

94da9193a6 ("grep: add support for PCRE v2", 2017-06-01) introduced
a small memory leak visible with valgrind in t7813.

Complete the creation of a PCRE2 specific variable that was missing from
the original change and free the generated table just like it is done
for PCRE1.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
---
 grep.c | 7 ++++---
 grep.h | 1 +
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/grep.c b/grep.c
index e748a6d68c..3e14ec91a6 100644
--- a/grep.c
+++ b/grep.c
@@ -524,7 +524,6 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 	PCRE2_UCHAR errbuf[256];
 	PCRE2_SIZE erroffset;
 	int options = PCRE2_MULTILINE;
-	const uint8_t *character_tables = NULL;
 	int jitret;
 	int patinforet;
 	size_t jitsizearg;
@@ -535,9 +534,10 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 
 	if (opt->ignore_case) {
 		if (has_non_ascii(p->pattern)) {
-			character_tables = pcre2_maketables(pcre2_global_context);
+			p->pcre2_tables = pcre2_maketables(pcre2_global_context);
 			p->pcre2_compile_context = pcre2_compile_context_create(NULL);
-			pcre2_set_character_tables(p->pcre2_compile_context, character_tables);
+			pcre2_set_character_tables(p->pcre2_compile_context,
+							p->pcre2_tables);
 		}
 		options |= PCRE2_CASELESS;
 	}
@@ -642,6 +642,7 @@ static void free_pcre2_pattern(struct grep_pat *p)
 	pcre2_match_data_free(p->pcre2_match_data);
 	pcre2_jit_stack_free(p->pcre2_jit_stack);
 	pcre2_match_context_free(p->pcre2_match_context);
+	free((void *)p->pcre2_tables);
 }
 #else /* !USE_LIBPCRE2 */
 static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)
diff --git a/grep.h b/grep.h
index 526c2db9ef..533165c21a 100644
--- a/grep.h
+++ b/grep.h
@@ -96,6 +96,7 @@ struct grep_pat {
 	pcre2_compile_context *pcre2_compile_context;
 	pcre2_match_context *pcre2_match_context;
 	pcre2_jit_stack *pcre2_jit_stack;
+	const uint8_t *pcre2_tables;
 	uint32_t pcre2_jit_on;
 	kwset_t kws;
 	unsigned fixed:1;
-- 
2.23.0.rc1