Async scan + bugfixes (#947)

* Support asynchronous WiFi scan

* Fixed buffer overflow in getChipId

* ESP compatibility fixes

* fixup! ESP compatibility fixes

cores/rp2040/RP2040Support.h

@@ -325,7 +325,7 @@ public:
     }
 
     const char *getChipID() {
-        static char id[PICO_UNIQUE_BOARD_ID_SIZE_BYTES + 1] = { 0 };
+        static char id[2 * PICO_UNIQUE_BOARD_ID_SIZE_BYTES + 1] = { 0 };
         if (!id[0]) {
             pico_get_unique_board_id_string(id, sizeof(id));
         }

libraries/ArduinoOTA/src/ArduinoOTA.cpp

@@ -110,7 +110,7 @@ void ArduinoOTAClass::begin(bool useMDNS) {
     _useMDNS = useMDNS;
 
     if (!_hostname.length()) {
-        char tmp[15];
+        char tmp[2 * PICO_UNIQUE_BOARD_ID_SIZE_BYTES + 6];
         sprintf(tmp, "pico-%s", rp2040.getChipID());
         _hostname = tmp;
     }

libraries/WiFi/src/WiFiClass.cpp

@@ -44,17 +44,20 @@ const char* WiFiClass::firmwareVersion() {
     return PICO_SDK_VERSION_STRING;
 }
 
-void WiFiClass::mode(_wifiModeESP m) {
+void WiFiClass::mode(WiFiMode_t m) {
     _calledESP = true;
     switch (m) {
-    case WIFI_OFF:
+    case WiFiMode_t::WIFI_OFF:
         end();
         break;
-    case WIFI_AP:
-        _modeESP = WIFI_AP;
+    case WiFiMode_t::WIFI_AP:
+        _modeESP = WiFiMode_t::WIFI_AP;
         break;
-    case WIFI_STA:
-        _modeESP = WIFI_STA;
+    case WiFiMode_t::WIFI_STA:
+        _modeESP = WiFiMode_t::WIFI_STA;
+        break;
+    case WiFiMode_t::WIFI_AP_STA:
+        _modeESP = WiFiMode_t::WIFI_STA;
         break;
     }
 }
@@ -86,7 +89,7 @@ int WiFiClass::begin(const char* ssid, const char *passphrase) {
 
     _ssid = ssid;
     _password = passphrase;
-    _wifi.setSSID(ssid);
+    _wifi.setSSID(_ssid.c_str());
     _wifi.setPassword(passphrase);
     _wifi.setTimeout(_timeout);
     _wifi.setSTA();
@@ -123,7 +126,7 @@ uint8_t WiFiClass::beginAP(const char *ssid, const char* passphrase) {
 
     _ssid = ssid;
     _password = passphrase;
-    _wifi.setSSID(ssid);
+    _wifi.setSSID(_ssid.c_str());
     _wifi.setPassword(passphrase);
     _wifi.setTimeout(_timeout);
     _wifi.setAP();
@@ -234,7 +237,7 @@ const char *WiFiClass::getHostname() {
 
     return: one value of wl_status_t enum
 */
-int WiFiClass::disconnect(void) {
+int WiFiClass::disconnect(bool wifi_off __unused) {
     if (_dhcpServer) {
         dhcp_server_deinit(_dhcpServer);
         free(_dhcpServer);
@@ -300,7 +303,7 @@ IPAddress WiFiClass::gatewayIP() {
 
     return: ssid string
 */
-const char* WiFiClass::SSID() {
+const String &WiFiClass::SSID() {
     return _ssid;
 }
 
@@ -396,7 +399,7 @@ int WiFiClass::_scanCB(void *env, const cyw43_ev_scan_result_t *result) {
 
     return: Number of discovered networks
 */
-int8_t WiFiClass::scanNetworks() {
+int8_t WiFiClass::scanNetworks(bool async) {
     cyw43_wifi_scan_options_t scan_options;
     memset(&scan_options, 0, sizeof(scan_options));
     _scan.clear();
@@ -409,11 +412,27 @@ int8_t WiFiClass::scanNetworks() {
     if (err) {
         return 0;
     }
+    if (!async) {
         uint32_t now = millis();
         while (cyw43_wifi_scan_active(&cyw43_state) && (millis() - now < 10000)) {
             delay(10);
         }
         return _scan.size();
+    } else {
+        return -1;
+    }
+}
+
+int8_t WiFiClass::scanComplete() {
+    if (cyw43_wifi_scan_active(&cyw43_state)) {
+        return -1;
+    } else {
+        return _scan.size();
+    }
+}
+
+void WiFiClass::scanDelete() {
+    _scan.clear();
 }
 
 /*

libraries/WiFi/src/WiFiClass.h

@@ -35,7 +35,7 @@
 
 typedef void(*FeedHostProcessorWatchdogFuncPointer)();
 
-typedef enum { WIFI_STA, WIFI_AP, WIFI_OFF } _wifiModeESP; // For ESP8266 compatibility
+typedef enum { WIFI_OFF = 0, WIFI_STA = 1, WIFI_AP = 2, WIFI_AP_STA = 3 } WiFiMode_t; // For ESP8266 compatibility
 
 class WiFiClass {
 public:
@@ -46,7 +46,18 @@ public:
     */
     static const char* firmwareVersion();
 
-    void mode(_wifiModeESP m); // For ESP8266 compatibility
+    void mode(WiFiMode_t m); // For ESP8266 compatibility
+
+    WiFiMode_t getMode() {
+        if (_wifiHWInitted) {
+            if (_apMode) {
+                return WiFiMode_t::WIFI_AP;
+            } else {
+                return WiFiMode_t::WIFI_STA;
+            }
+        }
+        return WiFiMode_t::WIFI_OFF;
+    };
 
     /*  Start WiFi connection for OPEN networks
 
@@ -138,7 +149,7 @@ public:
     }
 
     String softAPSSID() {
-        return String(SSID());
+        return SSID();
     }
 
 
@@ -205,7 +216,7 @@ public:
 
         return: one value of wl_status_t enum
     */
-    int disconnect(void);
+    int disconnect(bool wifi_off = false);
 
     void end(void);
 
@@ -249,7 +260,7 @@ public:
 
         return: ssid string
     */
-    const char* SSID();
+    const String &SSID();
 
     /*
         Return the current BSSID associated with the network.
@@ -281,9 +292,23 @@ public:
     /*
         Start scan WiFi networks available
 
+        param async: whether to perform asynchronous scan
+
         return: Number of discovered networks
     */
-    int8_t scanNetworks();
+    int8_t scanNetworks(bool async = false);
+
+    /*
+        Return number of scanned WiFi networks
+
+        return: Number of discovered networks
+    */
+    int8_t scanComplete();
+
+    /*
+        Delete scan results
+    */
+    void scanDelete();
 
     /*
         Return the SSID discovered during the network scan.
@@ -357,8 +382,8 @@ public:
 
 private:
     int _timeout = 10000;
-    const char * _ssid = nullptr;
-    const char * _password = nullptr;
+    String _ssid;
+    String _password;
     bool _wifiHWInitted = false;
     bool _apMode = false;
 
@@ -371,7 +396,7 @@ private:
 
     // ESP compat
     bool _calledESP = false; // Should we behave like the ESP8266 for connect?
-    _wifiModeESP _modeESP = WIFI_STA;
+    WiFiMode_t _modeESP = WIFI_STA;
 };
 
 extern WiFiClass WiFi;