ESP8266: Timeout if chip keeps returning errors

The ESP chip returns timeout, but keeps trying to connect, so we want to
keep track of time ourselves, instead of relying on the chip's timeout.
This fixes failing WIFI-CONNECT-SECURE-FAIL test.

Author: michalpasztamobica

components/wifi/esp8266-driver/ESP8266Interface.cpp

@@ -184,13 +184,20 @@ void ESP8266Interface::_connect_async()
         return;
     }
     _connect_retval = _esp.connect(ap_ssid, ap_pass);
+    int timeleft_ms = ESP8266_INTERFACE_CONNECT_TIMEOUT_MS - _conn_timer.read_ms();
     if (_connect_retval == NSAPI_ERROR_OK || _connect_retval == NSAPI_ERROR_AUTH_FAILURE
-            || _connect_retval == NSAPI_ERROR_NO_SSID) {
+            || _connect_retval == NSAPI_ERROR_NO_SSID
+            || ((_if_blocking == true) && (timeleft_ms <= 0))) {
         _connect_event_id = 0;
+        _conn_timer.stop();
+        if (timeleft_ms <= 0) {
+            _connect_retval = NSAPI_ERROR_CONNECTION_TIMEOUT;
+        }
         _if_connected.notify_all();
     } else {
         // Postpone to give other stuff time to run
-        _connect_event_id = _global_event_queue->call_in(ESP8266_CONNECT_TIMEOUT, callback(this, &ESP8266Interface::_connect_async));
+        _connect_event_id = _global_event_queue->call_in(ESP8266_INTERFACE_CONNECT_INTERVAL_MS,
+                                                         callback(this, &ESP8266Interface::_connect_async));
         if (!_connect_event_id) {
             MBED_ERROR(MBED_MAKE_ERROR(MBED_MODULE_DRIVER, MBED_ERROR_CODE_ENOMEM), \
                        "ESP8266Interface::_connect_async(): unable to add event to queue. Increase \"events.shared-eventsize\"\n");
@@ -233,6 +240,9 @@ int ESP8266Interface::connect()
 
     _connect_retval = NSAPI_ERROR_NO_CONNECTION;
     MBED_ASSERT(!_connect_event_id);
+    _conn_timer.stop();
+    _conn_timer.reset();
+    _conn_timer.start();
     _connect_event_id = _global_event_queue->call(callback(this, &ESP8266Interface::_connect_async));
 
     if (!_connect_event_id) {

components/wifi/esp8266-driver/ESP8266Interface.h

@@ -19,6 +19,7 @@
 
 #if DEVICE_SERIAL && DEVICE_INTERRUPTIN && defined(MBED_CONF_EVENTS_PRESENT) && defined(MBED_CONF_NSAPI_PRESENT) && defined(MBED_CONF_RTOS_PRESENT)
 #include "drivers/DigitalOut.h"
+#include "drivers/Timer.h"
 #include "ESP8266/ESP8266.h"
 #include "events/EventQueue.h"
 #include "events/mbed_shared_queues.h"
@@ -34,6 +35,9 @@
 
 #define ESP8266_SOCKET_COUNT 5
 
+#define ESP8266_INTERFACE_CONNECT_INTERVAL_MS (5000)
+#define ESP8266_INTERFACE_CONNECT_TIMEOUT_MS (2 * ESP8266_CONNECT_TIMEOUT + ESP8266_INTERFACE_CONNECT_INTERVAL_MS)
+
 #ifdef TARGET_FF_ARDUINO
 #ifndef MBED_CONF_ESP8266_TX
 #define MBED_CONF_ESP8266_TX D1
@@ -94,6 +98,9 @@ class ESP8266Interface : public NetworkStack, public WiFiInterface {
      *
      *  Attempts to connect to a WiFi network.
      *
+     *  If interface is configured blocking it will timeout after up to
+     *  ESP8266_INTERFACE_CONNECT_TIMEOUT_MS + ESP8266_CONNECT_TIMEOUT ms.
+     *
      *  @param ssid      Name of the network to connect to
      *  @param pass      Security passphrase to connect to the network
      *  @param security  Type of encryption for connection (Default: NSAPI_SECURITY_NONE)
@@ -408,6 +415,7 @@ class ESP8266Interface : public NetworkStack, public WiFiInterface {
 
     // connect status reporting
     nsapi_error_t _conn_status_to_error();
+    mbed::Timer _conn_timer;
 
     // Drivers's socket info
     struct _sock_info {