From 01e78ed33327a4f8944f2b118f2c35dc237614e5 Mon Sep 17 00:00:00 2001
From: Teufelchen1 <bennet.blischke@haw-hamburg.de>
Date: Thu, 18 Apr 2024 17:18:01 +0200
Subject: [PATCH] cpu/esp: Handle format print errors

---
 cpu/esp_common/lib_printf.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/cpu/esp_common/lib_printf.c b/cpu/esp_common/lib_printf.c
index 538683ef3b61..78bfa6805090 100644
--- a/cpu/esp_common/lib_printf.c
+++ b/cpu/esp_common/lib_printf.c
@@ -46,6 +46,16 @@ static int _lib_printf(int level, const char* tag, const char* format, va_list a
 
     int len = vsnprintf(_printf_buf, PRINTF_BUFSIZ - 1, format, arg);
 
+    if (len < 0) {
+        ESP_EARLY_LOGI(tag, "Failed to format print");
+        return 0;
+    }
+
+    /* Did the output get truncated? */
+    if ((unsigned) len > PRINTF_BUFSIZ - 1) {
+        len = PRINTF_BUFSIZ - 1;
+    }
+
     /*
      * Since ESP_EARLY_LOG macros add a line break at the end, a terminating
      * line break in the output must be removed if there is one.