app: Add automatic data reception for sockets

A new AT-command #XRECVCFG can be used to set the
automatic data reception for the sockets. When the automatic
data reception is activated, the data received for the socket
is immediately sent to host as URC.

Signed-off-by: Markus Lassila <markus.lassila@nordicsemi.no>

Author: MarkusLassila

app/src/sm_at_host.c

@@ -132,6 +132,8 @@ static bool exit_datamode(void)
 		rsp_send("\r\n#XDATAMODE: %d\r\n", datamode_handler_result);
 		datamode_handler_result = 0;
 
+		sm_at_socket_notify_datamode_exit();
+
 		LOG_INF("Exit datamode");
 		ret = true;
 	}
@@ -873,6 +875,11 @@ bool in_datamode(void)
 	return (get_sm_mode() == SM_DATA_MODE);
 }
 
+bool in_at_mode(void)
+{
+	return (get_sm_mode() == SM_AT_COMMAND_MODE);
+}
+
 bool exit_datamode_handler(int result)
 {
 	bool ret = false;

app/src/sm_at_host.h

@@ -164,6 +164,13 @@ int enter_datamode(sm_datamode_handler_t handler, size_t data_len);
  */
 bool in_datamode(void);
 
+/**
+ * @brief Check whether Serial Modem AT host is in AT command mode
+ *
+ * @retval true if yes, false if no.
+ */
+bool in_at_mode(void);
+
 /**
  * @brief Exit the data mode handler
  *