WiFiServerStream fix & host connection callback

- fixed client accept in WiFiServerStream
- added host connection callback hook to notfiy connect and disconnect

Author: jnsbyr

utility/WiFiClientStream.h

@@ -15,12 +15,12 @@
   See file LICENSE.txt for further informations on licensing terms.
 
   Parts of this class are based on
-  
+
   - EthernetClientStream - Copyright (C) 2013 Norbert Truchsess. All rights reserved.
-  
+
   published under the same license.
 
-  Last updated April 15th, 2016
+  Last updated April 17th, 2016
  */
 
 #ifndef WIFI_CLIENT_STREAM_H
@@ -55,9 +55,14 @@ class WiFiClientStream : public WiFiStream
       if( millis() - _time_connect >= MILLIS_RECONNECT )
       {
         _connected = _client.connect( _remote_ip, _port );
-        if( !_connected ) {
+        if( !_connected )
+        {
           _time_connect = millis();
         }
+        else if ( _currentHostConnectionCallback )
+        {
+          (*_currentHostConnectionCallback)(HOST_CONNECTION_CONNECTED);
+        }
       }
     }
 
@@ -87,6 +92,10 @@ class WiFiClientStream : public WiFiStream
     if( _client)
     {
       _client.stop();
+      if ( _currentHostConnectionCallback )
+      {
+        (*_currentHostConnectionCallback)(HOST_CONNECTION_DISCONNECTED);
+      }
     }
     _connected = false;
     _time_connect = millis();

utility/WiFiServerStream.h

@@ -20,7 +20,7 @@
 
   published under the same license.
 
-  Last updated April 16th, 2016
+  Last updated April 17th, 2016
  */
 
 #ifndef WIFI_SERVER_STREAM_H
@@ -49,8 +49,12 @@ class WiFiServerStream : public WiFiStream
 
     // passive TCP connect (accept)
     WiFiClient newClient = _server.available();
-    if( !_client ) return false;  // could this work on all platforms? if( !(_client && _client.connected()) ) return false;
+    if( !newClient ) return false;
     _client = newClient;
+    if ( _currentHostConnectionCallback )
+    {
+      (*_currentHostConnectionCallback)(HOST_CONNECTION_CONNECTED);
+    }
 
     return true;
   }
@@ -90,6 +94,10 @@ class WiFiServerStream : public WiFiStream
     if( _client)
     {
       _client.stop();
+      if ( _currentHostConnectionCallback )
+      {
+        (*_currentHostConnectionCallback)(HOST_CONNECTION_DISCONNECTED);
+      }
     }
     _connected = false;
   }

utility/WiFiStream.h

@@ -15,20 +15,29 @@
 
   See file LICENSE.txt for further informations on licensing terms.
 
-  Last updated April 15th, 2016
+  Last updated April 17th, 2016
  */
- 
+
 #ifndef WIFI_STREAM_H
 #define WIFI_STREAM_H
 
 #include <inttypes.h>
 #include <Stream.h>
 
+#define HOST_CONNECTION_DISCONNECTED 0
+#define HOST_CONNECTION_CONNECTED    1
+
+extern "C" {
+  // callback function types
+  typedef void (*hostConnectionCallbackFunction)(byte);
+}
+
 class WiFiStream : public Stream
 {
 protected:
   WiFiClient _client;
   bool _connected = false;
+  hostConnectionCallbackFunction _currentHostConnectionCallback;
 
   //configuration members
   IPAddress _local_ip;                // DHCP
@@ -54,6 +63,7 @@ class WiFiStream : public Stream
   /** constructor for TCP client */
   WiFiStream(IPAddress server_ip, uint16_t server_port) : _remote_ip(server_ip), _port(server_port) {}
 
+  inline void attach( hostConnectionCallbackFunction newFunction ) { _currentHostConnectionCallback = newFunction; }
 
 /******************************************************************************
  *           network configuration