Merge pull request #256 from bcsanches/master

Keep Ethernet singleton "alive" until connection is established.

EthernetInterface.cpp

@@ -36,7 +36,16 @@ EthernetInterface * EthernetInterface::singleton=NULL;
 void EthernetInterface::setup()
 {
     singleton=new EthernetInterface();
-    if (!singleton->connected) singleton=NULL; 
+
+    DIAG(F("Ethernet begin OK."));
+     if (Ethernet.hardwareStatus() == EthernetNoHardware) {
+      DIAG(F("Ethernet shield not found"));
+
+      delete singleton;
+      singleton=NULL;
+
+      return;
+    }     
 };
 
 
@@ -61,37 +70,17 @@ EthernetInterface::EthernetInterface()
         return;
     } 
     #endif       
-    DIAG(F("begin OK."));
-     if (Ethernet.hardwareStatus() == EthernetNoHardware) {
-      DIAG(F("Ethernet shield not found"));
-      return;
 }
 
-    unsigned long startmilli = millis();
+/**
-    while ((millis() - startmilli) < 5500) // Loop to give time to check for cable connection
+ * @brief Cleanup any resources
+ * 
+ * @return none
+ */
+EthernetInterface::~EthernetInterface()
 {
-        if (Ethernet.linkStatus() == LinkON)
+    delete server;
-            break;
+    delete outboundRing;
-        DIAG(F("Ethernet waiting for link (1sec) "));
-        delay(1000);
-    }
-
-    if (Ethernet.linkStatus() == LinkOFF) {
-      DIAG(F("Ethernet cable not connected"));
-      return;
-    }
-    
-    connected=true;
-    
-    IPAddress ip = Ethernet.localIP(); // reassign the obtained ip address
-
-    server = new EthernetServer(IP_PORT); // Ethernet Server listening on default port IP_PORT
-    server->begin();
-  
-    LCD(4,F("IP: %d.%d.%d.%d"), ip[0], ip[1], ip[2], ip[3]);
-    LCD(5,F("Port:%d"), IP_PORT);
-
-    outboundRing=new RingStream(OUTBOUND_RING_SIZE);     
 }
 
 /**
@@ -100,7 +89,8 @@ EthernetInterface::EthernetInterface()
  */
 void EthernetInterface::loop()
 {    
-    if (!singleton) return;
+    if(!singleton || (!singleton->checkLink()))
+        return;
     
     switch (Ethernet.maintain())
     {
@@ -125,6 +115,60 @@ void EthernetInterface::loop()
 
 }
 
+/**
+ * @brief Checks ethernet link cable status and detects when it connects / disconnects
+ * 
+ * @return true when cable is connected, false otherwise
+ */
+bool EthernetInterface::checkLink()
+{    
+    if (Ethernet.linkStatus() == LinkON)
+    {
+        //if we are not connected yet, setup a new server
+        if(!connected)
+        {
+            DIAG(F("Ethernet cable connected"));
+    
+            connected=true;
+            
+            IPAddress ip = Ethernet.localIP(); // reassign the obtained ip address
+
+            server = new EthernetServer(IP_PORT); // Ethernet Server listening on default port IP_PORT
+            server->begin();
+        
+            LCD(4,F("IP: %d.%d.%d.%d"), ip[0], ip[1], ip[2], ip[3]);
+            LCD(5,F("Port:%d"), IP_PORT);
+
+            //
+            //only create a outboundRing it none exists, this may happen if the cable gets disconnected and connected again
+            if(!outboundRing)
+                outboundRing=new RingStream(OUTBOUND_RING_SIZE);   
+        }
+
+        return true;
+    }        
+    else if(connected)
+    {
+        DIAG(F("Ethernet cable disconnected"));
+        connected=false;
+
+        //clean up any client
+        for (byte socket = 0; socket < MAX_SOCK_NUM; socket++)
+        {
+            if(clients[socket].connected())
+                clients[socket].stop();
+        }            
+
+        /* tear down server */
+        delete server;
+        server = nullptr;
+
+        LCD(4,F("IP: None"));
+    }
+
+    return false;
+}
+
  void EthernetInterface::loop2()
 {
     // get client from the server

EthernetInterface.h

@@ -59,11 +59,15 @@ class EthernetInterface {
      static EthernetInterface * singleton;
      bool connected;
      EthernetInterface();
+     ~EthernetInterface();
      void loop2();
-    EthernetServer * server;
+
+     bool checkLink();
+
+    EthernetServer * server = nullptr;
     EthernetClient clients[MAX_SOCK_NUM];                // accept up to MAX_SOCK_NUM client connections at the same time; This depends on the chipset used on the Shield
     uint8_t buffer[MAX_ETH_BUFFER+1];                    // buffer used by TCP for the recv
-    RingStream * outboundRing;
+    RingStream * outboundRing = nullptr;
   
 };