[PATCH 1/4] string-list: allow passing NULL for `get_entry_index`

[shejialuo <shejialuo@gmail.com>]

Callers of `get_entry_index()` are required to pass a non-NULL
`exact_match` parameter to receive information about whether an exact
match is found. However, in some cases, callers only need the index
position.

Let's allow callers to pass NULL for the `exact_match` parameter
when they don't need this information, reducing unnecessary variable
declarations in calling code.

Signed-off-by: shejialuo <shejialuo@gmail.com>
---
 string-list.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/string-list.c b/string-list.c
index 343cf1ca90..bf358d1a5c 100644
--- a/string-list.c
+++ b/string-list.c
@@ -29,12 +29,14 @@ static size_t get_entry_index(const struct string_list *list, const char *string
 		else if (compare > 0)
 			left = middle + 1;
 		else {
-			*exact_match = 1;
+			if (exact_match)
+				*exact_match = 1;
 			return middle;
 		}
 	}
 
-	*exact_match = 0;
+	if (exact_match)
+		*exact_match = 0;
 	return right;
 }
 
-- 
2.51.0