Fix warnings (#2881)

* Suppressed -Wunused-parameter and -Wunused-function by casting to void unused identifiers.

* Explicit initialization of all fields to suppress -Wmissing-field-initializers.

* Fixed signed/unsigned integer comparison.

* memset initialization of structs.

* More -Wunused-parameter fixes.

libraries/ESP8266WiFi/src/ESP8266WiFiGeneric.cpp

@@ -153,6 +153,7 @@ WiFiEventHandler ESP8266WiFiGenericClass::onStationModeGotIP(std::function<void(
 WiFiEventHandler ESP8266WiFiGenericClass::onStationModeDHCPTimeout(std::function<void(void)> f)
 {
     WiFiEventHandler handler = std::make_shared<WiFiEventHandlerOpaque>(WIFI_EVENT_STAMODE_DHCP_TIMEOUT, [f](System_Event_t* e){
+        (void) e;
         f();
     });
     sCbEventList.push_back(handler);
@@ -452,6 +453,7 @@ int ESP8266WiFiGenericClass::hostByName(const char* aHostname, IPAddress& aResul
  * @param callback_arg
  */
 void wifi_dns_found_callback(const char *name, ip_addr_t *ipaddr, void *callback_arg) {
+    (void) name;
     if(ipaddr) {
         (*reinterpret_cast<IPAddress*>(callback_arg)) = ipaddr->addr;
     }

libraries/ESP8266WiFi/src/WiFiClient.cpp

@@ -135,6 +135,7 @@ int WiFiClient::connect(IPAddress ip, uint16_t port)
 
 int8_t WiFiClient::_connected(void* pcb, int8_t err)
 {
+    (void) err;
     tcp_pcb* tpcb = reinterpret_cast<tcp_pcb*>(pcb);
     _client = new ClientContext(tpcb, 0, 0);
     _client->ref();
@@ -144,6 +145,7 @@ int8_t WiFiClient::_connected(void* pcb, int8_t err)
 
 void WiFiClient::_err(int8_t err)
 {
+    (void) err;
     DEBUGV(":err %d\r\n", err);
     esp_schedule();
 }
@@ -177,6 +179,7 @@ size_t WiFiClient::write(const uint8_t *buf, size_t size)
 
 size_t WiFiClient::write(Stream& stream, size_t unused)
 {
+    (void) unused;
     return WiFiClient::write(stream);
 }
 

libraries/ESP8266WiFi/src/WiFiClientSecure.cpp

@@ -214,6 +214,7 @@ public:
 
     static ClientContext* getIOContext(int fd)
     {
+        (void) fd;
         return s_io_ctx;
     }
 
@@ -623,6 +624,7 @@ extern "C" void ax_port_write() __attribute__ ((weak, alias("__ax_port_write")))
 
 extern "C" int __ax_get_file(const char *filename, uint8_t **buf)
 {
+    (void) filename;
     *buf = 0;
     return 0;
 }
@@ -637,6 +639,8 @@ extern "C" void ax_get_file() __attribute__ ((weak, alias("__ax_get_file")));
 
 extern "C" void* ax_port_malloc(size_t size, const char* file, int line)
 {
+    (void) file;
+    (void) line;
     void* result = malloc(size);
     if (result == nullptr) {
         DEBUG_TLS_MEM_PRINT("%s:%d malloc %d failed, left %d\r\n", file, line, size, ESP.getFreeHeap());
@@ -656,6 +660,8 @@ extern "C" void* ax_port_calloc(size_t size, size_t count, const char* file, int
 
 extern "C" void* ax_port_realloc(void* ptr, size_t size, const char* file, int line)
 {
+    (void) file;
+    (void) line;
     void* result = realloc(ptr, size);
     if (result == nullptr) {
         DEBUG_TLS_MEM_PRINT("%s:%d realloc %d failed, left %d\r\n", file, line, size, ESP.getFreeHeap());

libraries/ESP8266WiFi/src/WiFiServer.cpp

@@ -97,6 +97,7 @@ bool WiFiServer::hasClient() {
 }
 
 WiFiClient WiFiServer::available(byte* status) {
+    (void) status;
     if (_unclaimed) {
         WiFiClient result(_unclaimed);
         _unclaimed = _unclaimed->next();
@@ -134,6 +135,8 @@ size_t WiFiServer::write(uint8_t b) {
 size_t WiFiServer::write(const uint8_t *buffer, size_t size) {
     // write to all clients
     // not implemented
+    (void) buffer;
+    (void) size;
     return 0;
 }
 
@@ -149,6 +152,7 @@ T* slist_append_tail(T* head, T* item) {
 }
 
 int8_t WiFiServer::_accept(tcp_pcb* apcb, int8_t err) {
+    (void) err;
     DEBUGV("WS:ac\r\n");
     ClientContext* client = new ClientContext(apcb, &WiFiServer::_s_discard, this);
     _unclaimed = slist_append_tail(_unclaimed, client);
@@ -157,6 +161,7 @@ int8_t WiFiServer::_accept(tcp_pcb* apcb, int8_t err) {
 }
 
 void WiFiServer::_discard(ClientContext* client) {
+    (void) client;
     // _discarded = slist_append_tail(_discarded, client);
     DEBUGV("WS:dis\r\n");
 }

libraries/ESP8266WiFi/src/include/ClientContext.h

@@ -372,6 +372,8 @@ protected:
 
     err_t _sent(tcp_pcb* pcb, uint16_t len)
     {
+        (void) pcb;
+        (void) len;
         DEBUGV(":sent %d\r\n", len);
         _write_some_from_cb();
         return ERR_OK;
@@ -405,6 +407,8 @@ protected:
 
     recv_ret_t _recv(tcp_pcb* pcb, pbuf* pb, err_t err)
     {
+        (void) pcb;
+        (void) err;
         if(pb == 0) { // connection closed
             DEBUGV(":rcl\r\n");
             _cancel_write();
@@ -425,6 +429,7 @@ protected:
 
     void _error(err_t err)
     {
+        (void) err;
         DEBUGV(":er %d %08x\r\n", err, (uint32_t) _datasource);
         tcp_arg(_pcb, NULL);
         tcp_sent(_pcb, NULL);

libraries/ESP8266WiFi/src/include/DataSource.h

@@ -75,6 +75,7 @@ public:
 
     void release_buffer(const uint8_t* buffer, size_t size) override
     {
+        (void) buffer;
         _pos += size;
     }
 

libraries/ESP8266WiFi/src/include/UdpContext.h

@@ -330,6 +330,9 @@ private:
     void _recv(udp_pcb *upcb, pbuf *pb,
             ip_addr_t *addr, u16_t port)
     {
+        (void) upcb;
+        (void) addr;
+        (void) port;
         if (_rx_buf)
         {
             // there is some unread data