Add not listening check in WiFiServer::available()

In case WiFi interface goes down and all sockets are closed.

Author: sandeepmistry

src/WiFiServer.cpp

@@ -46,6 +46,11 @@ uint8_t WiFiServer::begin(uint8_t opt)
 	addr.sin_port = _htons(_port);
 	addr.sin_addr.s_addr = 0;
 
+	if (_socket != -1) {
+		WiFiSocket.close(_socket);
+		_socket = -1;
+	}
+
 	// Open TCP server socket.
 	if ((_socket = WiFiSocket.create(AF_INET, SOCK_STREAM, opt)) < 0) {
 		return 0;
@@ -74,6 +79,10 @@ WiFiClient WiFiServer::available(uint8_t* status)
 		*status = 0;
 	}
 
+	if (_socket != -1 && !WiFiSocket.listening(_socket)) {
+		_socket = -1;
+	}
+
 	if (_socket != -1) {
 		SOCKET child = WiFiSocket.accepted(_socket);
 

src/utility/WiFiSocket.cpp

@@ -165,6 +165,13 @@ uint8 WiFiSocketClass::connected(SOCKET sock)
 	return (_info[sock].state == SOCKET_STATE_CONNECTED);
 }
 
+uint8 WiFiSocketClass::listening(SOCKET sock)
+{
+	m2m_wifi_handle_events(NULL);
+
+	return (_info[sock].state == SOCKET_STATE_LISTENING);
+}
+
 int WiFiSocketClass::available(SOCKET sock)
 {
 	m2m_wifi_handle_events(NULL);

src/utility/WiFiSocket.h

@@ -39,6 +39,7 @@ class WiFiSocketClass {
   sint8 setopt(SOCKET socket, uint8 u8Level, uint8 option_name, const void *option_value, uint16 u16OptionLen);
   sint8 connect(SOCKET sock, struct sockaddr *pstrAddr, uint8 u8AddrLen);
   uint8 connected(SOCKET sock);
+  uint8 listening(SOCKET sock);
   int available(SOCKET sock);
   int peek(SOCKET sock);
   int read(SOCKET sock, uint8_t* buf, size_t size);