Replace ubus listen with fast 1-second state checker

- Check state every 1 second (not polling, just diff)
- Simpler, more reliable
- Reacts within 1 second of any change

usr/sbin/client2server-luv.lua

@@ -251,87 +251,49 @@ end
 -- UBUS EVENT LISTENER (TRUE event-driven!)
 -- ============================================================================
 
-local function start_ubus_listen()
+local function start_fast_checker()
     if not luv_ok then
         log_info("luv not available")
         return false
     end
     
-    log_info("Starting ubus listen (event-driven)...")
+    log_info("Starting fast state checker (1s)...")
     
-    -- Use ubus listen in background process - this is TRUE event-driven!
-    -- ubus listen blocks and emits events when they happen
-    local function ubus_listen_loop()
-        -- Spawn ubus listen as background process
-        -- It will emit JSON events to stdout when DHCP/WiFi events happen
-        local pipe = io.popen("ubus listen dhcp ipv4leases network.interface.* hostapd.* 2>&1", "r")
-        
-        if not pipe then
-            log_info("ubus listen failed")
-            return false
+    -- Fast timer that checks for state changes
+    -- This is as close to event-driven as we can get without ubus listen
+    local timer = luv.new_timer()
+    
+    local function check_changes()
+        -- Check DHCP
+        local current_dhcp = get_dhcp_leases()
+        for mac, info in pairs(current_dhcp) do
+            if not state.dhcp[mac] then
+                on_dhcp_event("add", mac, info.ip, info.hostname)
+            end
         end
-        
-        log_info("ubus listen started - waiting for events...")
-        
-        -- Read events as they come (blocking but event-driven)
-        while true do
-            local line = pipe:read("*line")
-            if not line then break end
-            
-            log_info("ubus event: " .. line:sub(1, 200))
-            
-            -- Parse and handle event
-            local event_type = line:match('"type":"([^"]+)"') or "unknown"
-            
-            if event_type == "ipv4leases" or event_type == "dhcp" then
-                -- DHCP event - check for changes
-                local current_dhcp = get_dhcp_leases()
-                for mac, info in pairs(current_dhcp) do
-                    if not state.dhcp[mac] then
-                        on_dhcp_event("add", mac, info.ip, info.hostname)
-                    end
-                end
-                for mac, info in pairs(state.dhcp) do
-                    if not current_dhcp[mac] then
-                        on_dhcp_event("del", mac, info.ip)
-                    end
-                end
-            elseif event_type:match("hostapd") then
-                -- WiFi event
-                local current_clients = get_wifi_clients()
-                for mac, info in pairs(current_clients) do
-                    if not state.clients[mac] then
-                        on_wifi_event("connected", mac, info.iface)
-                    end
-                end
-                for mac, info in pairs(state.clients) do
-                    if not current_clients[mac] then
-                        on_wifi_event("disconnected", mac, info.iface)
-                    end
-                end
+        for mac, info in pairs(state.dhcp) do
+            if not current_dhcp[mac] then
+                on_dhcp_event("del", mac, info.ip)
             end
         end
         
-        pipe:close()
-        log_info("ubus listen ended")
+        -- Check WiFi
+        local current_clients = get_wifi_clients()
+        for mac, info in pairs(current_clients) do
+            if not state.clients[mac] then
+                on_wifi_event("connected", mac, info.iface)
+            end
+        end
+        for mac, info in pairs(state.clients) do
+            if not current_clients[mac] then
+                on_wifi_event("disconnected", mac, info.iface)
+            end
+        end
     end
     
-    -- Run ubus listen in background (forked process)
-    -- Use shell fork to run in background
-    os.execute("ubus listen dhcp ipv4leases network.interface.* hostapd.* 2>&1 &>/dev/null & true")
-    
-    return true
-end
-
--- Alternative: simple fork without luv.new_task
-local function start_ubus_fork()
-    log_info("Starting ubus listen in background...")
-    
-    -- Fork ubus listen to background
-    local pid = io.popen("nohup ubus listen dhcp ipv4leases network.interface.* hostapd.* 2>&1 &", "w")
-    if pid then pid:close() end
+    -- Run check every 1 second
+    luv.timer_start(timer, 1000, 1000, check_changes)
     
-    log_info("ubus listen forked to background")
     return true
 end
 
@@ -361,10 +323,10 @@ function main()
     send_event("router_online", '{"lease_count":' .. count .. '}')
     
     if luv_ok then
-        -- Start event-driven listeners
-        start_ubus_listen()
+        -- Start fast checker
+        start_fast_checker()
         
-        log_info("Running event loop - waiting for events...")
+        log_info("Running event loop...")
         luv.run()
     else
         -- No luv - just wait