lib: implement wcsnlen

This will come in handy for implementing %ls in the follow up commit.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20211122084732.2597109-19-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 9 insertions, 0 deletions

diff --git a/lib/wchar.c b/lib/wchar.c
index 3be228b5a7..250538dd85 100644
--- a/lib/wchar.c
+++ b/lib/wchar.c
@@ -28,6 +28,15 @@ size_t wcslen(const wchar_t *s)
 	return len;
 }
 
+size_t wcsnlen(const wchar_t * s, size_t count)
+{
+	const wchar_t *sc;
+
+	for (sc = s; count-- && *sc != L'\0'; ++sc)
+		/* nothing */;
+	return sc - s;
+}
+
 wchar_t *strdup_wchar(const wchar_t *src)
 {
 	int len = wcslen(src);