init: do not count file descriptors for HTTPServer if -server=0

src/init.cpp

@@ -1084,6 +1084,10 @@ bool AppInitParameterInteraction(const ArgsManager& args)
     if (user_rpc_max_connections < 1) {
         return InitError(Untranslated("-rpcmaxconnections must be greater than zero. Use -server=0 to disable HTTP."));
     }
+    if (!args.GetBoolArg("-server", false)) {
+        num_rpc_bind = 0;
+        user_rpc_max_connections = 0;
+    }
 
     // Reserve enough FDs to account for the bare minimum, plus any manual connections, plus the bound interfaces.
     // Every element is an int >= 0 so summing in int64_t cannot overflow.

test/functional/feature_init.py

@@ -408,6 +408,16 @@ class InitTest(BitcoinTestFramework):
                 match=ErrorMatch.PARTIAL_REGEX
             )
 
+        # Start without the HTTP server to ensure that -rpcmaxconnections is ignored
+        with node.assert_debug_log(
+            expected_msgs = ["net thread start"],
+            unexpected_msgs = ["Initialized HTTP server"],
+            timeout = 10
+        ):
+            node.start(extra_args=[f"-rpcmaxconnections={2**64}", "-server=0"])
+        # No HTTP server, no RPC `stop`
+        node.kill_process()
+
     def run_test(self):
         self.init_pid_test()
         self.init_stress_test_interrupt()