[ping] Report timed-out pings via the callback function

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/pinger.c

 	size_t len;
 	/** Current sequence number */
 	uint16_t sequence;
+	/** Response for current sequence number is still pending */
+	int pending;
 
 	/** Callback function
 	 *
-	 * @v src		Source socket address
+	 * @v src		Source socket address, or NULL
 	 * @v sequence		Sequence number
 	 * @v len		Payload length
 	 * @v rc		Status code
 	struct io_buffer *iobuf;
 	int rc;
 
+	/* If no response has been received, notify the callback function */
+	if ( pinger->pending )
+		pinger->callback ( NULL, pinger->sequence, 0, -ETIMEDOUT );
+	pinger->pending = 1;
+
 	/* Increase sequence number */
 	pinger->sequence++;
 
 	uint16_t sequence = meta->offset;
 	int rc;
 
+	/* Clear response pending flag, if applicable */
+	if ( sequence == pinger->sequence )
+		pinger->pending = 0;
+
 	/* Check for errors */
 	if ( len != pinger->len ) {
 		DBGC ( pinger, "PINGER %p received incorrect length %zd "

src/usr/pingmgmt.c

 /**
  * Display ping result
  *
- * @v src		Source socket address
+ * @v src		Source socket address, or NULL
  * @v sequence		Sequence number
  * @v len		Payload length
  * @v rc		Status code
 
 	/* Display ping response */
 	printf ( "%zd bytes from %s: seq=%d",
-		 len, sock_ntoa ( peer ), sequence );
+		 len, ( peer ? sock_ntoa ( peer ) : "<none>" ), sequence );
 	if ( rc != 0 )
 		printf ( ": %s", strerror ( rc ) );
 	printf ( "\n" );