libsaria: Return default track values in error case

If we can't find the inode, I return some default values to the UI to
keep it happy (and clear out the information from the previous song).

include/libsaria/track.h

@@ -11,6 +11,7 @@ class Track
 		TrackTag *tags;
 
 	public:
+		Track();
 		Track(ino_t, TrackTag *);
 		~Track();
 

libsaria/current.cpp

@@ -18,9 +18,11 @@ namespace libsaria
 	void current_track(void (*func)(Track &))
 	{
 		ino_t inode;
-		/* TODO: Set to blank in error cases */
-		if (current_inode(inode) < 0)
+		if (current_inode(inode) < 0) {
+			Track blank;
+			func(blank);
 			return;
+		}
 		library::get_info(inode, func);
 	}
 

libsaria/track.cpp

@@ -2,6 +2,12 @@
 #include <libsaria/track.h>
 #include <libsaria/tags.h>
 
+Track::Track()
+{
+	inode = 0;
+	tags  = NULL;
+}
+
 Track::Track(ino_t ino, TrackTag *tag)
 {
 	inode = ino;
@@ -19,30 +25,42 @@ ino_t Track::get_inode()
 
 unsigned int Track::get_track()
 {
-	return tags->get_track();
+	if (tags)
+		return tags->get_track();
+	return 0;
 }
 
 string Track::get_title()
 {
-	return tags->get_title();
+	if (tags)
+		return tags->get_title();
+	return "";
 }
 
 string Track::get_lenstr()
 {
-	return tags->get_lenstr();
+	if (tags)
+		return tags->get_lenstr();
+	return "";
 }
 
 string Track::get_artist()
 {
-	return tags->get_artist();
+	if (tags)
+		return tags->get_artist();
+	return "";
 }
 
 string Track::get_album()
 {
-	return tags->get_album();
+	if (tags)
+		return tags->get_album();
+	return "";
 }
 
 unsigned int Track::get_year()
 {
-	return tags->get_year();
+	if (tags)
+		return tags->get_year();
+	return 0;
 }