From f95ae569879390bb6521636764857e413fde17ca Mon Sep 17 00:00:00 2001
From: Jonathan Lassoff <jof@thejof.com>
Date: Sun, 21 Apr 2024 17:18:27 -0700
Subject: [PATCH] is_callsign(): Check size of callsign before indexing into it

---
 Radio.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Radio.cpp b/Radio.cpp
index 0c2ae989..06301f60 100644
--- a/Radio.cpp
+++ b/Radio.cpp
@@ -85,7 +85,7 @@ namespace Radio
 
   bool is_callsign (QString const& callsign)
   {
-    if ((!callsign.at(1).isDigit() && callsign.size () == 2) || callsign == "F" || callsign == "G" || callsign == "I" || callsign == "K" || callsign == "W") {
+    if ((callsign.size() > 1 && !callsign.at(1).isDigit() && callsign.size() == 2) || callsign == "F" || callsign == "G" || callsign == "I" || callsign == "K" || callsign == "W") {
         auto call = callsign + "0";
         return call.contains (valid_callsign_regexp);
     }