1) Converted ping status codes to enum;

2) Changed ping_cb to reflect new status code enum;
3) Removed pingGateway() method;
4) Corrected bug where ping(const char* hostname, uint8_t ttl) returned WL_PING_ERROR when host was unresolved instead of WL_PING_UNKNOWN_HOST;
5) Updated WiFiPing example sketch.

Author: PKGeorgiev

examples/WiFiPing/WiFiPing.ino

@@ -10,7 +10,7 @@
 
  created 13 July 2010
  by dlf (Metodo2 srl)
- modified 13 May 2016
+ modified 09 June 2016
  by Petar Georgiev
  */
 #include <SPI.h>
@@ -64,14 +64,10 @@ void loop() {
   pingResult = WiFi.ping(hostName);
 
   if (pingResult == WL_PING_SUCCESS){
-    Serial.println("SUCCESS");
+    Serial.println("SUCCESS!");
   } else {
-    switch (pingResult){
-      case WL_PING_DEST_UNREACHABLE: { Serial.println("Destination host unreachable"); }; break;
-      case WL_PING_TIMEOUT: { Serial.println("Request Timed Out"); }; break;
-      case WL_PING_UNKNOWN_HOST: { Serial.println("Unable to resolve hostname to IP Address"); }; break;
-      case WL_PING_ERROR: { Serial.println("Internal error"); }; break;  
-    };      
+	Serial.print("FAILED! Error code: ");
+	Serial.println(pingResult);     
   };
 
   delay(3000);

src/WiFi.cpp

@@ -148,13 +148,31 @@ static void resolve_cb(uint8_t * /* hostName */, uint32_t hostIp)
 }
 
 static void ping_cb(uint32 u32IPAddr, uint32 u32RTT, uint8 u8ErrorCode) {
-  if (u8ErrorCode == 0)
-    if (WiFi._resolve == u32IPAddr)
-      WiFi._resolve = WL_PING_SUCCESS;
-    else
-      WiFi._resolve = WL_PING_DEST_UNREACHABLE;
-  else
-    WiFi._resolve = u8ErrorCode;
+	switch(u8ErrorCode){
+		
+		// PING_ERR_SUCCESS
+		case 0: {
+			// Ensure that reply IP address matches requested IP address
+			if (WiFi._resolve == u32IPAddr)
+			  WiFi._resolve = WL_PING_SUCCESS;
+			else
+			  // Another network device replied to the our ICMP request
+			  WiFi._resolve = WL_PING_DEST_UNREACHABLE;			
+		}; break;
+		
+		// PING_ERR_DEST_UNREACH
+		case 1: {
+			WiFi._resolve = WL_PING_DEST_UNREACHABLE;
+		}; break;
+		
+		// PING_ERR_TIMEOUT
+		case 2: {
+			WiFi._resolve = WL_PING_TIMEOUT;
+		}; break;
+		
+		// Unknown error codes
+		default: WiFi._resolve = WL_PING_ERROR;
+	};
 };
 
 WiFiClass::WiFiClass()
@@ -733,19 +751,19 @@ void WiFiClass::refresh(void)
 	m2m_wifi_handle_events(NULL);
 }
 
-uint8_t WiFiClass::ping(const char* hostname, uint8_t ttl){
+wl_ping_result_t WiFiClass::ping(const char* hostname, uint8_t ttl){
 	IPAddress ip;
 	if (hostByName(hostname, ip) > 0)
 		return ping(ip, ttl);
 	else
-		return WL_PING_ERROR;
+		return WL_PING_UNKNOWN_HOST;
 };
 
-uint8_t WiFiClass::ping(const String &hostname, uint8_t ttl){
+wl_ping_result_t WiFiClass::ping(const String &hostname, uint8_t ttl){
 	return ping(hostname.c_str(), ttl);
 };
 
-uint8_t WiFiClass::ping(IPAddress host, uint8_t ttl) {
+wl_ping_result_t WiFiClass::ping(IPAddress host, uint8_t ttl) {
 
   // Network led ON (rev A then rev B).
   m2m_periph_gpio_set_val(M2M_PERIPH_GPIO16, 0);
@@ -775,12 +793,7 @@ uint8_t WiFiClass::ping(IPAddress host, uint8_t ttl) {
   if (_resolve == dstHost)
     return WL_PING_TIMEOUT;
   else
-    return _resolve;
-};
-
-uint8_t WiFiClass::pingGateway(){
-	return ping(_gateway);
-	
+    return (wl_ping_result_t)_resolve;
 };
 
 WiFiClass WiFi;

src/WiFi101.h

@@ -61,11 +61,13 @@ typedef enum {
 	WL_AP_MODE
 } wl_mode_t;
 
-#define WL_PING_SUCCESS 0
-#define WL_PING_DEST_UNREACHABLE 1
-#define WL_PING_TIMEOUT 2
-#define WL_PING_UNKNOWN_HOST 3
-#define WL_PING_ERROR 4	
+typedef enum {
+	WL_PING_SUCCESS = 0,
+	WL_PING_DEST_UNREACHABLE,
+	WL_PING_TIMEOUT,
+	WL_PING_UNKNOWN_HOST,
+	WL_PING_ERROR
+} wl_ping_result_t;
 
 class WiFiClass
 {
@@ -144,10 +146,9 @@ class WiFiClass
 	int hostByName(const char* hostname, IPAddress& result);
 	int hostByName(const String &hostname, IPAddress& result) { return hostByName(hostname.c_str(), result); }
 
-	uint8_t ping(const char* hostname, uint8_t ttl = 128);
-	uint8_t ping(const String &hostname, uint8_t ttl = 128);
-	uint8_t ping(IPAddress host, uint8_t ttl = 128);
-	uint8_t pingGateway();
+	wl_ping_result_t ping(const char* hostname, uint8_t ttl = 128);
+	wl_ping_result_t ping(const String &hostname, uint8_t ttl = 128);
+	wl_ping_result_t ping(IPAddress host, uint8_t ttl = 128);
 
 	void refresh(void);