From 9f329101a1767e63e0d9dbc1a758f4775c2f2fc9 Mon Sep 17 00:00:00 2001
From: jonny_ji7 <jonny@wwad.de>
Date: Mon, 22 Aug 2022 22:22:45 +0200
Subject: [PATCH] Fix bug display lib: random characters flickering

Fix bug in display library where random chars were written to display even
though the array has ended.
Resulting in random character appearing briefly when only first display got written.

-> stop loop when 0-termination of char array is reached
---
 components/max7219/max7219.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/components/max7219/max7219.c b/components/max7219/max7219.c
index fd8939c..5a59893 100644
--- a/components/max7219/max7219.c
+++ b/components/max7219/max7219.c
@@ -236,7 +236,7 @@ esp_err_t max7219_draw_text_7seg(max7219_t *dev, uint8_t pos, const char *s)
 {
     CHECK_ARG(dev && s);
 
-    while (s && pos < dev->digits)
+    while (*s != '\0' && pos < dev->digits)
     {
         uint8_t c = get_char(dev, *s);
         if (*(s + 1) == '.')