From a600f265e1f9439dedd2c52114a3d12f300d8203 Mon Sep 17 00:00:00 2001
From: dmiller <dmiller@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Fri, 17 Jul 2026 21:56:29 +0000
Subject: [PATCH] Replace repeated strcat with Snprintf

---
 main.cc | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/main.cc b/main.cc
index a9bab3223..bdfd3d918 100644
--- a/main.cc
+++ b/main.cc
@@ -142,13 +142,22 @@ int main(int argc, char *argv[]) {
 
  try {
   if ((cptr = getenv("NMAP_ARGS"))) {
-    if (Snprintf(command, sizeof(command), "nmap %s", cptr) >= (int) sizeof(command)) {
-        error("Warning: NMAP_ARGS variable is too long, truncated");
+    char *tail = command;
+    int rem = sizeof(command);
+    int n = Snprintf(tail, rem, "nmap %s", cptr);
+    if (n >= rem) {
+        fatal("NMAP_ARGS variable is too long");
     }
+    tail += n;
+    rem -= n;
     /* copy rest of command-line arguments */
-    for (i = 1; i < argc && strlen(command) + strlen(argv[i]) + 1 < sizeof(command); i++) {
-      strcat(command, " ");
-      strcat(command, argv[i]);
+    for (i = 1; i < argc; i++) {
+      n = Snprintf(tail, rem, " %s", argv[i]);
+      if (n >= rem) {
+        fatal("NMAP_ARGS and command line together exceed %lu bytes", sizeof(command));
+      }
+      tail += n;
+      rem -= n;
     }
     myargc = arg_parse(command, &myargv);
     if (myargc < 1) {