Add WiFi close notifications (#799)

* Start adding support for WiFi notifications

* Add wifi closed notifications

* Add is_closed to ethernet

* Update gold

* Reflow comment

* Drop tabs

lib/core/events.toit

@@ -12,11 +12,14 @@ monitor ResourceState_:
   group: return group_
   resource: return resource_
 
+  set_callback callback/Lambda -> none:
+    callback_ = callback
+
   wait_for_state bits:
     return wait_for_state_ bits
 
   wait:
-    return wait_for_state_ 0xffffff
+    return wait_for_state_ 0x3fff_ffff
 
   clear:
     state_ = 0
@@ -29,15 +32,19 @@ monitor ResourceState_:
       unregister_monitor_notifier_ group_ resource_
       resource_ = null
       group_ = null
+      callback_ = null
       remove_finalizer this
 
   // Called on timeouts and when the state changes because of the call
   // to [register_object_notifier] in the constructor.
   notify_:
     resource := resource_
     if resource:
-      state := read_state_ group_ resource
-      state_ |= state
+      state := state_ | (read_state_ group_ resource)
+      state_ = state
+      callback := callback_
+      if callback:
+        callback.call state
     // Always call the super implementation to avoid getting
     // into a situation, where timeouts might be ignored.
     super
@@ -55,6 +62,7 @@ monitor ResourceState_:
 
   group_ := ?
   resource_ := ?
+  callback_/Lambda? := null
   state_ := 0
 
 read_state_ module id:

lib/net/ethernet.toit

@@ -166,6 +166,9 @@ class EthernetInterface_ implements net.Interface:
       return it.address
     unreachable
 
+  is_closed -> bool:
+    return not open_
+
   close -> none:
     if not open_: return
     open_ = false

lib/net/impl.toit

@@ -20,7 +20,6 @@ open -> net.Interface:
   if not service: throw "Network unavailable"
   return SystemInterface_ service service.connect
 
-// TODO(kasper): Find a way to listen for network closing.
 class SystemInterface_ extends NetworkResource implements net.Interface:
   // The proxy mask contains bits for all the operations that must be
   // proxied through the service client. The service definition tells the
@@ -33,7 +32,7 @@ class SystemInterface_ extends NetworkResource implements net.Interface:
     super service handle
 
   address -> net.IpAddress:
-    if not handle_: throw "Network closed"
+    if is_closed: throw "Network closed"
     if (proxy_mask_ & NetworkService.PROXY_ADDRESS) != 0: return super
     socket := Socket
     try:
@@ -45,13 +44,17 @@ class SystemInterface_ extends NetworkResource implements net.Interface:
     finally:
       socket.close
 
+  on_notified_ notification/any -> none:
+    if notification == NetworkService.NOTIFY_CLOSED:
+      task:: close
+
   resolve host/string -> List:
-    if not handle_: throw "Network closed"
+    if is_closed: throw "Network closed"
     if (proxy_mask_ & NetworkService.PROXY_RESOLVE) != 0: return super host
     return [dns.dns_lookup host]
 
   udp_open --port/int?=null -> udp.Socket:
-    if not handle_: throw "Network closed"
+    if is_closed: throw "Network closed"
     if (proxy_mask_ & NetworkService.PROXY_UDP) != 0: return super --port=port
     return Socket "0.0.0.0" (port ? port : 0)
 
@@ -61,14 +64,14 @@ class SystemInterface_ extends NetworkResource implements net.Interface:
         net.SocketAddress ips[0] port
 
   tcp_connect address/net.SocketAddress -> tcp.Socket:
-    if not handle_: throw "Network closed"
+    if is_closed: throw "Network closed"
     if (proxy_mask_ & NetworkService.PROXY_TCP) != 0: return super address
     result := TcpSocket
     result.connect address.ip.stringify address.port
     return result
 
   tcp_listen port/int -> tcp.ServerSocket:
-    if not handle_: throw "Network closed"
+    if is_closed: throw "Network closed"
     if (proxy_mask_ & NetworkService.PROXY_TCP) != 0: return super port
     result := TcpServerSocket
     result.listen "0.0.0.0" port

lib/net/net.toit

@@ -17,6 +17,8 @@ open -> Interface:
 
 interface Interface implements udp.Interface tcp.Interface:
   address -> IpAddress
+  is_closed -> bool
+
   resolve host/string -> List
 
   udp_open -> udp.Socket
@@ -26,4 +28,4 @@ interface Interface implements udp.Interface tcp.Interface:
   tcp_connect address/SocketAddress -> tcp.Socket
   tcp_listen port/int -> tcp.ServerSocket
 
-  close
+  close -> none

lib/system/api/network.toit

@@ -35,6 +35,12 @@ interface NetworkService:
   static SOCKET_OPTION_UDP_BROADCAST /int ::= 0
   static SOCKET_OPTION_TCP_NO_DELAY  /int ::= 100
 
+  /**
+  The notification constants are used as arguments to $ServiceResource.notify_
+    and consequently $ServiceResourceProxy.on_notified_.
+  */
+  static NOTIFY_CLOSED /int ::= 200
+
   // The connect call returns a handle to the network resource and
   // the proxy mask bits in a list. The proxy mask bits indicate
   // which operations the service definition wants the client to

lib/system/services.toit

@@ -253,6 +253,9 @@ abstract class ServiceResourceProxy:
     if _handle_ & 1 == 1:
       ServiceResourceProxyManager_.instance.register client_.id _handle_ this
 
+  is_closed -> bool:
+    return _handle_ == null
+
   handle_ -> int:
     return _handle_
 

src/resources/wifi_esp32.cc

@@ -36,9 +36,10 @@ namespace toit {
 
 enum {
   WIFI_CONNECTED    = 1 << 0,
-  WIFI_DHCP_SUCCESS = 1 << 1,
-  WIFI_DISCONNECTED = 1 << 2,
-  WIFI_RETRY        = 1 << 3,
+  WIFI_IP_ASSIGNED  = 1 << 1,
+  WIFI_IP_LOST      = 1 << 2,
+  WIFI_DISCONNECTED = 1 << 3,
+  WIFI_RETRY        = 1 << 4,
 };
 
 const int kInvalidWifi = -1;
@@ -117,11 +118,12 @@ class WifiEvents : public SystemResource {
     FATAL_IF_NOT_ESP_OK(esp_wifi_stop());
   }
 
-  uint8_t disconnect_reason() { return _disconnect_reason; }
+  uint8 disconnect_reason() const { return _disconnect_reason; }
+  void set_disconnect_reason(uint8 reason) { _disconnect_reason = reason; }
 
  private:
   friend class WifiResourceGroup;
-  uint8_t _disconnect_reason;
+  uint8 _disconnect_reason;
 };
 
 class IPEvents : public SystemResource {
@@ -135,7 +137,7 @@ class IPEvents : public SystemResource {
     free(_ip);
   }
 
-  const char* ip() {
+  const char* ip() const {
     return _ip;
   }
 
@@ -164,7 +166,7 @@ uint32_t WifiResourceGroup::on_event(Resource* resource, word data, uint32_t sta
           state |= WIFI_DISCONNECTED;
           break;
       }
-      static_cast<WifiEvents*>(resource)->_disconnect_reason = reason;
+      static_cast<WifiEvents*>(resource)->set_disconnect_reason(reason);
       break;
     }
 
@@ -175,34 +177,46 @@ uint32_t WifiResourceGroup::on_event(Resource* resource, word data, uint32_t sta
     case WIFI_EVENT_STA_STOP:
       break;
 
+    case WIFI_EVENT_STA_BEACON_TIMEOUT:
+      // The beacon timeout mechanism is used by ESP32 station to detect whether the AP
+      // is alive or not. If the station continuously loses 60 beacons of the connected
+      // AP, the beacon timeout happens.
+      //
+      // After the beacon times out, the station sends 5 probe requests to the AP. If
+      // still no probe response or beacon is received from AP, the station disconnects
+      // from the AP and raises the WIFI_EVENT_STA_DISCONNECTED event.
+      break;
+
     case IP_EVENT_STA_GOT_IP: {
       ip_event_got_ip_t* event = reinterpret_cast<ip_event_got_ip_t*>(system_event->event_data);
       uint32_t addr = event->ip_info.ip.addr;
-      sprintf(static_cast<IPEvents*>(resource)->_ip,
+      sprintf(
+          static_cast<IPEvents*>(resource)->_ip,
 #ifdef CONFIG_IDF_TARGET_ESP32C3
-              "%lu.%lu.%lu.%lu",
+          "%lu.%lu.%lu.%lu",
 #else
-	      "%d.%d.%d.%d",
+          "%d.%d.%d.%d",
 #endif
-              (addr >> 0) & 0xff,
-              (addr >> 8) & 0xff,
-              (addr >> 16) & 0xff,
-              (addr >> 24) & 0xff);
-      state |= WIFI_DHCP_SUCCESS;
+          (addr >> 0) & 0xff,
+          (addr >> 8) & 0xff,
+          (addr >> 16) & 0xff,
+          (addr >> 24) & 0xff);
+      state |= WIFI_IP_ASSIGNED;
       break;
     }
 
     case IP_EVENT_STA_LOST_IP:
+      state |= WIFI_IP_LOST;
       break;
 
     default:
       printf(
 #ifdef CONFIG_IDF_TARGET_ESP32C3
-        "unhandled WiFi event: %lu\n",
+          "unhandled WiFi event: %lu\n",
 #else
-	"unhandled Wifi event: %d\n",
+          "unhandled WiFi event: %d\n",
 #endif
-        system_event->id
+          system_event->id
       );
   }