add lws_is_ssl api

Suggested by Michael Harbler on the mailing list

Signed-off-by: Andy Green <andy.green@linaro.org>

changelog

@@ -16,6 +16,11 @@ be used by the user code to mark the selected protocol by user-defined version
 or capabliity flag information, for the case multiple versions of a protocol are
 supported.
 
+int lws_is_ssl(wsi) added to allow user code to know if the connection was made
+over ssl or not.  If LWS_SERVER_OPTION_ALLOW_NON_SSL_ON_SSL_PORT is used, both
+ssl and non-ssl connections are possible and may need to be treated differently
+in the user code.
+
 
 v1.3-chrome37-firefox30
 =======================

lib/libwebsockets.c

@@ -755,3 +755,17 @@ LWS_VISIBLE void lws_set_log_level(int level, void (*log_emit_function)(int leve
 	if (log_emit_function)
 		lwsl_emit = log_emit_function;
 }
+
+/**
+ * lws_use_ssl() - Find out if connection is using SSL
+ * @wsi:	websocket connection to check
+ *
+ *	Returns 0 if the connection is not using SSL, 1 if using SSL and
+ *	using verified cert, and 2 if using SSL but the cert was not
+ *	checked (appears for client wsi told to skip check on connection)
+ */
+LWS_VISIBLE int
+lws_is_ssl(struct libwebsocket *wsi)
+{
+	return wsi->use_ssl;
+}

lib/libwebsockets.h

@@ -1181,6 +1181,9 @@ lws_send_pipe_choked(struct libwebsocket *wsi);
 LWS_VISIBLE LWS_EXTERN int
 lws_frame_is_binary(struct libwebsocket *wsi);
 
+LWS_VISIBLE LWS_EXTERN int
+lws_is_ssl(struct libwebsocket *wsi);
+
 LWS_VISIBLE LWS_EXTERN unsigned char *
 libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md);