fix: print correct address in accept() debug log for IPv6

darkhttpd.c

@@ -1360,11 +1360,22 @@ static void accept_connection(void) {
     }
     LIST_INSERT_HEAD(&connlist, conn, entries);
 
-    if (debug)
-        printf("accepted connection from %s:%u (fd %d)\n",
-               inet_ntoa(addrin.sin_addr),
-               ntohs(addrin.sin_port),
-               conn->socket);
+    if (debug) {
+#ifdef HAVE_INET6
+        if (inet6) {
+            printf("accepted connection from [%s]:%u (fd %d)\n",
+                   get_address_text(&addrin6.sin6_addr),
+                   ntohs(addrin6.sin6_port),
+                   conn->socket);
+        } else
+#endif
+        {
+            printf("accepted connection from %s:%u (fd %d)\n",
+                   inet_ntoa(addrin.sin_addr),
+                   ntohs(addrin.sin_port),
+                   conn->socket);
+        }
+    }
 
     /* Try to read straight away rather than going through another iteration
      * of the select() loop.

devel/run-tests

@@ -59,6 +59,38 @@ runtests() {
   # Should exit immediately.
   ./a.out $DIR --port $PORT --ipv6 --addr 127.0.0.1 2>&1 | grep -F "malformed --addr argument" > /dev/null || exit 1
 
+  echo "===> run IPv6 accept() debug log test (regression: was printing garbage IPv4 address)"
+  ./a.out $DIR --port $PORT --ipv6 --addr ::1 \
+    >test.out.ipv6debug 2>>test.out.stderr &
+  PID=$!
+  kill -0 $PID || exit 1
+  $PYTHON -c "
+import socket, sys, time
+for _ in range(50):
+    try:
+        s = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
+        s.settimeout(2)
+        s.connect(('::1', $PORT, 0, 0))
+        s.send(b'GET / HTTP/1.0\r\nConnection: close\r\n\r\n')
+        try: s.recv(65536)
+        except: pass
+        s.close()
+        sys.exit(0)
+    except OSError:
+        s.close()
+        time.sleep(0.05)
+print('FAIL: could not connect to IPv6 server', file=sys.stderr)
+sys.exit(1)
+  " || { kill $PID; exit 1; }
+  kill $PID
+  wait $PID
+  grep -qF "accepted connection from [::1]:" test.out.ipv6debug || {
+    echo "FAIL: IPv6 debug accept log should contain [::1]:PORT but got:"
+    cat test.out.ipv6debug
+    exit 1
+  }
+  rm -f test.out.ipv6debug
+
   echo "===> run tests against a basic instance (generates darkhttpd.gcda)"
   ./a.out $DIR --port $PORT --addr $ADDR --log test.out.log \
     >>test.out.stdout 2>>test.out.stderr &