playlist/cue/CueParser: use std::unique_ptr

src/playlist/cue/CueParser.cxx

@@ -22,20 +22,12 @@
 #include "util/Alloc.hxx"
 #include "util/StringUtil.hxx"
 #include "util/CharUtil.hxx"
-#include "DetachedSong.hxx"
 #include "tag/Tag.hxx"
 
 #include <assert.h>
 #include <string.h>
 #include <stdlib.h>
 
-CueParser::~CueParser()
-{
-	delete current;
-	delete previous;
-	delete finished;
-}
-
 static const char *
 cue_next_word(char *p, char **pp)
 {
@@ -160,9 +152,9 @@ CueParser::Commit()
 	assert(!current->GetTag().IsDefined());
 	current->SetTag(song_tag.Commit());
 
-	finished = previous;
-	previous = current;
-	current = nullptr;
+	finished = std::move(previous);
+	previous = std::move(current);
+	current.reset();
 }
 
 void
@@ -237,7 +229,7 @@ CueParser::Feed2(char *p)
 		}
 
 		state = TRACK;
-		current = new DetachedSong(filename);
+		current.reset(new DetachedSong(filename));
 		assert(!current->GetTag().IsDefined());
 
 		song_tag = header_tag;
@@ -297,11 +289,9 @@ CueParser::Get()
 		   deliver all remaining (partial) results */
 		assert(current == nullptr);
 
-		finished = previous;
-		previous = nullptr;
+		finished = std::move(previous);
+		previous.reset();
 	}
 
-	DetachedSong *song = finished;
-	finished = nullptr;
-	return song;
+	return finished.release();
 }