From 24c3bfb681463a2b6d7de7efdc9a2e279440541f Mon Sep 17 00:00:00 2001
From: 0x1eef <0x1eef@protonmail.com>
Date: Fri, 25 Aug 2023 18:25:20 -0300
Subject: [PATCH] Handle 'str' being NULL

---
 src/isinetaddr.c       | 3 ++-
 test/isinetaddr_test.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/isinetaddr.c b/src/isinetaddr.c
index 87146af..125096e 100644
--- a/src/isinetaddr.c
+++ b/src/isinetaddr.c
@@ -19,8 +19,9 @@ isinetaddr(const char *str)
 {
   char buf[4];
   int i = 0, j = 0, k = 0;
-  size_t len = strnlen(str, 16);
+  size_t len;
 
+  len = str == NULL ? 0 : strnlen(str, 16);
   for(size_t l = 0; l < len; l++) {
     if (str[l] == '.') {
       if (inrange(buf)) {
diff --git a/test/isinetaddr_test.c b/test/isinetaddr_test.c
index 325a78c..1ee63de 100644
--- a/test/isinetaddr_test.c
+++ b/test/isinetaddr_test.c
@@ -18,7 +18,8 @@ const char *invalid[] = {
   "192.168.1.1..",
   "192.168.1.1a",
   "555555555555555555555555555555555",
-  ""
+  "",
+  NULL
 };
 
 int