Make port structure opaque.

libserialport.h.in

@@ -226,18 +226,7 @@ enum sp_signal {
 };
 
 /** A serial port. */
-struct sp_port {
-	/** Name used to open the port. */
-	char *name;
-/** @cond 0 */
-	/** OS-specific port handle. */
-#ifdef _WIN32
-	HANDLE hdl;
-#else
-	int fd;
-#endif
-/** @endcond */
-};
+struct sp_port;
 
 /** Configuration for a serial port. */
 struct sp_port_config {
@@ -281,6 +270,21 @@ struct sp_port_config {
  */
 enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_ptr);
 
+/**
+ * Get the name of a port.
+ *
+ * The name returned is whatever is normally used to refer to a port on the
+ * current operating system; e.g. for Windows it will usually be a "COMn"
+ * device name, and for Unix it will be a device path beginning with "/dev/".
+ *
+ * @param port Pointer to port structure.
+ *
+ * @return The port name, or NULL if an invalid port is passed. The name
+ * string is part of the port structure and may not be used after the
+ * port structure has been freed.
+ */
+char *sp_get_port_name(const struct sp_port *port);
+
 /**
  * Free a port structure obtained from sp_get_port_by_name() or sp_copy_port().
  */

serialport.c

@@ -58,6 +58,15 @@
 
 #include "libserialport.h"
 
+struct sp_port {
+	char *name;
+#ifdef _WIN32
+	HANDLE hdl;
+#else
+	int fd;
+#endif
+};
+
 struct port_data {
 #ifdef _WIN32
 	DCB dcb;
@@ -184,6 +193,16 @@ enum sp_return sp_get_port_by_name(const char *portname, struct sp_port **port_p
 	RETURN_OK();
 }
 
+char *sp_get_port_name(const struct sp_port *port)
+{
+	TRACE("%p", port);
+
+	if (!port)
+		return NULL;
+
+	RETURN_VALUE("%s", port->name);
+}
+
 enum sp_return sp_copy_port(const struct sp_port *port, struct sp_port **copy_ptr)
 {
 	TRACE("%p, %p", port, copy_ptr);