playlist/SongEnumerator: wrap song in std::unique_ptr

src/playlist/CloseSongEnumerator.cxx

@@ -20,6 +20,7 @@
 #include "config.h"
 #include "CloseSongEnumerator.hxx"
 #include "input/InputStream.hxx"
+#include "DetachedSong.hxx"
 
 CloseSongEnumerator::~CloseSongEnumerator()
 {
@@ -27,7 +28,7 @@ CloseSongEnumerator::~CloseSongEnumerator()
 	delete is;
 }
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 CloseSongEnumerator::NextSong()
 {
 	return other->NextSong();

src/playlist/CloseSongEnumerator.hxx

@@ -41,7 +41,7 @@ public:
 
 	virtual ~CloseSongEnumerator();
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 #endif

src/playlist/MemorySongEnumerator.cxx

@@ -20,13 +20,13 @@
 #include "config.h"
 #include "MemorySongEnumerator.hxx"
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 MemorySongEnumerator::NextSong()
 {
 	if (songs.empty())
 		return nullptr;
 
-	auto result = new DetachedSong(std::move(songs.front()));
+	std::unique_ptr<DetachedSong> result(new DetachedSong(std::move(songs.front())));
 	songs.pop_front();
 	return result;
 }

src/playlist/MemorySongEnumerator.hxx

@@ -33,7 +33,7 @@ public:
 	MemorySongEnumerator(std::forward_list<DetachedSong> &&_songs)
 		:songs(std::move(_songs)) {}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 #endif

src/playlist/PlaylistQueue.cxx

@@ -44,24 +44,21 @@ playlist_load_into_queue(const char *uri, SongEnumerator &e,
 		? PathTraitsUTF8::GetParent(uri)
 		: std::string(".");
 
-	DetachedSong *song;
+	std::unique_ptr<DetachedSong> song;
 	for (unsigned i = 0;
 	     i < end_index && (song = e.NextSong()) != nullptr;
 	     ++i) {
 		if (i < start_index) {
 			/* skip songs before the start index */
-			delete song;
 			continue;
 		}
 
 		if (!playlist_check_translate_song(*song, base_uri.c_str(),
 						   loader)) {
-			delete song;
 			continue;
 		}
 
 		unsigned id = dest.AppendSong(pc, std::move(*song), error);
-		delete song;
 		if (id == 0)
 			return false;
 	}

src/playlist/Print.cxx

@@ -41,7 +41,7 @@ playlist_provider_print(Response &r, Partition &partition,
 		? PathTraitsUTF8::GetParent(uri)
 		: std::string(".");
 
-	DetachedSong *song;
+	std::unique_ptr<DetachedSong> song;
 	while ((song = e.NextSong()) != nullptr) {
 		if (playlist_check_translate_song(*song, base_uri.c_str(),
 						  loader) &&
@@ -51,8 +51,6 @@ playlist_provider_print(Response &r, Partition &partition,
 			/* fallback if no detail was requested or no
 			   detail was available */
 			song_print_uri(r, partition, *song);
-
-		delete song;
 	}
 }
 

src/playlist/SongEnumerator.hxx

@@ -20,6 +20,8 @@
 #ifndef MPD_SONG_ENUMERATOR_HXX
 #define MPD_SONG_ENUMERATOR_HXX
 
+#include <memory>
+
 class DetachedSong;
 
 /**
@@ -31,11 +33,10 @@ public:
 	virtual ~SongEnumerator() {}
 
 	/**
-	 * Obtain the next song.  The caller is responsible for
+	 * Obtain the next song.  Returns nullptr if there are no more
-	 * freeing the returned #Song object.  Returns nullptr if
+	 * songs.
-	 * there are no more songs.
 	 */
-	virtual DetachedSong *NextSong() = 0;
+	virtual std::unique_ptr<DetachedSong> NextSong() = 0;
 };
 
 #endif

src/playlist/plugins/CuePlaylistPlugin.cxx

@@ -36,7 +36,7 @@ class CuePlaylist final : public SongEnumerator {
 		:is(_is), tis(is) {
 	}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 static SongEnumerator *
@@ -45,23 +45,23 @@ cue_playlist_open_stream(InputStream &is)
 	return new CuePlaylist(is);
 }
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 CuePlaylist::NextSong()
 {
 	auto song = parser.Get();
 	if (song != nullptr)
-		return song.release();
+		return song;
 
 	const char *line;
 	while ((line = tis.ReadLine()) != nullptr) {
 		parser.Feed(line);
 		song = parser.Get();
 		if (song != nullptr)
-			return song.release();
+			return song;
 	}
 
 	parser.Finish();
-	return parser.Get().release();
+	return parser.Get();
 }
 
 static const char *const cue_playlist_suffixes[] = {

src/playlist/plugins/EmbeddedCuePlaylistPlugin.cxx

@@ -69,7 +69,7 @@ public:
 		delete parser;
 	}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 static void
@@ -124,13 +124,13 @@ embcue_playlist_open_uri(const char *uri,
 	return playlist;
 }
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 EmbeddedCuePlaylist::NextSong()
 {
 	auto song = parser->Get();
 	if (song != nullptr) {
 		song->SetURI(filename);
-		return song.release();
+		return song;
 	}
 
 	while (*next != 0) {
@@ -149,7 +149,7 @@ EmbeddedCuePlaylist::NextSong()
 		song = parser->Get();
 		if (song != nullptr) {
 			song->SetURI(filename);
-			return song.release();
+			return song;
 		}
 	}
 
@@ -157,7 +157,7 @@ EmbeddedCuePlaylist::NextSong()
 	song = parser->Get();
 	if (song != nullptr)
 		song->SetURI(filename);
-	return song.release();
+	return song;
 }
 
 static const char *const embcue_playlist_suffixes[] = {

src/playlist/plugins/ExtM3uPlaylistPlugin.cxx

@@ -48,7 +48,7 @@ public:
 		return strcmp(line, "#EXTM3U") == 0;
 	}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 static SongEnumerator *
@@ -105,7 +105,7 @@ extm3u_parse_tag(const char *line)
 	return tag.Commit();
 }
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 ExtM3uPlaylist::NextSong()
 {
 	Tag tag;
@@ -126,7 +126,7 @@ ExtM3uPlaylist::NextSong()
 		line_s = StripLeft(line_s);
 	} while (line_s[0] == '#' || *line_s == 0);
 
-	return new DetachedSong(line_s, std::move(tag));
+	return std::unique_ptr<DetachedSong>(new DetachedSong(line_s, std::move(tag)));
 }
 
 static const char *const extm3u_suffixes[] = {

src/playlist/plugins/FlacPlaylistPlugin.cxx

@@ -58,10 +58,10 @@ public:
 		FLAC__metadata_object_delete(cuesheet);
 	}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 FlacPlaylist::NextSong()
 {
 	const FLAC__StreamMetadata_CueSheet &c = cuesheet->data.cue_sheet;
@@ -82,7 +82,7 @@ FlacPlaylist::NextSong()
 		? c.tracks[next_track].offset
 		: total_samples;
 
-	auto *song = new DetachedSong(uri);
+	std::unique_ptr<DetachedSong> song(new DetachedSong(uri));
 	song->SetStartTime(SongTime::FromScale(start, sample_rate));
 	song->SetEndTime(SongTime::FromScale(end, sample_rate));
 	return song;

src/playlist/plugins/M3uPlaylistPlugin.cxx

@@ -33,7 +33,7 @@ public:
 		:tis(is) {
 	}
 
-	virtual DetachedSong *NextSong() override;
+	virtual std::unique_ptr<DetachedSong> NextSong() override;
 };
 
 static SongEnumerator *
@@ -42,7 +42,7 @@ m3u_open_stream(InputStream &is)
 	return new M3uPlaylist(is);
 }
 
-DetachedSong *
+std::unique_ptr<DetachedSong>
 M3uPlaylist::NextSong()
 {
 	char *line_s;
@@ -55,7 +55,7 @@ M3uPlaylist::NextSong()
 		line_s = Strip(line_s);
 	} while (line_s[0] == '#' || *line_s == 0);
 
-	return new DetachedSong(line_s);
+	return std::unique_ptr<DetachedSong>(new DetachedSong(line_s));
 }
 
 static const char *const m3u_suffixes[] = {

test/dump_playlist.cxx

@@ -108,7 +108,7 @@ try {
 
 	/* dump the playlist */
 
-	DetachedSong *song;
+	std::unique_ptr<DetachedSong> song;
 	while ((song = playlist->NextSong()) != NULL) {
 		printf("%s\n", song->GetURI());
 
@@ -127,8 +127,6 @@ try {
 			       (start_ms / 1000) % 60);
 
 		tag_save(stdout, song->GetTag());
-
-		delete song;
 	}
 
 	/* deinitialize everything */