filter/Plugin: return std::unique_ptr<PreparedFilter>

src/filter/plugins/AutoConvertFilterPlugin.cxx

@@ -62,13 +62,11 @@ class PreparedAutoConvertFilter final : public PreparedFilter {
 	/**
 	 * The underlying filter.
 	 */
-	PreparedFilter *const filter;
+	std::unique_ptr<PreparedFilter> filter;
 
 public:
-	PreparedAutoConvertFilter(PreparedFilter *_filter):filter(_filter) {}
-	~PreparedAutoConvertFilter() {
-		delete filter;
-	}
+	PreparedAutoConvertFilter(std::unique_ptr<PreparedFilter> _filter) noexcept
+		:filter(std::move(_filter)) {}
 
 	Filter *Open(AudioFormat &af) override;
 };
@@ -106,8 +104,8 @@ AutoConvertFilter::FilterPCM(ConstBuffer<void> src)
 	return filter->FilterPCM(src);
 }
 
-PreparedFilter *
-autoconvert_filter_new(PreparedFilter *filter)
+std::unique_ptr<PreparedFilter>
+autoconvert_filter_new(std::unique_ptr<PreparedFilter> filter) noexcept
 {
-	return new PreparedAutoConvertFilter(filter);
+	return std::make_unique<PreparedAutoConvertFilter>(std::move(filter));
 }

src/filter/plugins/AutoConvertFilterPlugin.hxx

@@ -20,6 +20,8 @@
 #ifndef MPD_AUTOCONVERT_FILTER_PLUGIN_HXX
 #define MPD_AUTOCONVERT_FILTER_PLUGIN_HXX
 
+#include <memory>
+
 class PreparedFilter;
 
 /**
@@ -28,7 +30,7 @@ class PreparedFilter;
  * requests a different format, it automatically creates a
  * convert_filter.
  */
-PreparedFilter *
-autoconvert_filter_new(PreparedFilter *filter);
+std::unique_ptr<PreparedFilter>
+autoconvert_filter_new(std::unique_ptr<PreparedFilter> filter) noexcept;
 
 #endif

src/filter/plugins/ChainFilterPlugin.cxx

@@ -67,13 +67,11 @@ public:
 class PreparedChainFilter final : public PreparedFilter {
 	struct Child {
 		const char *name;
-		PreparedFilter *filter;
+		std::unique_ptr<PreparedFilter> filter;
 
-		Child(const char *_name, PreparedFilter *_filter)
-			:name(_name), filter(_filter) {}
-		~Child() {
-			delete filter;
-		}
+		Child(const char *_name,
+		      std::unique_ptr<PreparedFilter> _filter)
+			:name(_name), filter(std::move(_filter)) {}
 
 		Child(const Child &) = delete;
 		Child &operator=(const Child &) = delete;
@@ -84,8 +82,9 @@ class PreparedChainFilter final : public PreparedFilter {
 	std::list<Child> children;
 
 public:
-	void Append(const char *name, PreparedFilter *filter) {
-		children.emplace_back(name, filter);
+	void Append(const char *name,
+		    std::unique_ptr<PreparedFilter> filter) noexcept {
+		children.emplace_back(name, std::move(filter));
 	}
 
 	/* virtual methods from class PreparedFilter */
@@ -143,17 +142,17 @@ ChainFilter::FilterPCM(ConstBuffer<void> src)
 	return src;
 }
 
-PreparedFilter *
-filter_chain_new(void)
+std::unique_ptr<PreparedFilter>
+filter_chain_new() noexcept
 {
-	return new PreparedChainFilter();
+	return std::make_unique<PreparedChainFilter>();
 }
 
 void
 filter_chain_append(PreparedFilter &_chain, const char *name,
-		    PreparedFilter *filter)
+		    std::unique_ptr<PreparedFilter> filter) noexcept
 {
 	PreparedChainFilter &chain = (PreparedChainFilter &)_chain;
 
-	chain.Append(name, filter);
+	chain.Append(name, std::move(filter));
 }

src/filter/plugins/ChainFilterPlugin.hxx

@@ -27,13 +27,15 @@
 #ifndef MPD_FILTER_CHAIN_HXX
 #define MPD_FILTER_CHAIN_HXX
 
+#include <memory>
+
 class PreparedFilter;
 
 /**
  * Creates a new filter chain.
  */
-PreparedFilter *
-filter_chain_new();
+std::unique_ptr<PreparedFilter>
+filter_chain_new() noexcept;
 
 /**
  * Appends a new filter at the end of the filter chain.  You must call
@@ -44,6 +46,6 @@ filter_chain_new();
  */
 void
 filter_chain_append(PreparedFilter &chain, const char *name,
-		    PreparedFilter *filter);
+		    std::unique_ptr<PreparedFilter> filter) noexcept;
 
 #endif

src/filter/plugins/ConvertFilterPlugin.cxx

@@ -119,10 +119,10 @@ ConvertFilter::FilterPCM(ConstBuffer<void> src)
 	return state.Convert(src);
 }
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 convert_filter_prepare() noexcept
 {
-	return new PreparedConvertFilter();
+	return std::make_unique<PreparedConvertFilter>();
 }
 
 Filter *

src/filter/plugins/ConvertFilterPlugin.hxx

@@ -20,11 +20,13 @@
 #ifndef MPD_CONVERT_FILTER_PLUGIN_HXX
 #define MPD_CONVERT_FILTER_PLUGIN_HXX
 
+#include <memory>
+
 class PreparedFilter;
 class Filter;
 struct AudioFormat;
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 convert_filter_prepare() noexcept;
 
 Filter *

src/filter/plugins/NormalizeFilterPlugin.cxx

@@ -53,10 +53,10 @@ public:
 	Filter *Open(AudioFormat &af) override;
 };
 
-static PreparedFilter *
+static std::unique_ptr<PreparedFilter>
 normalize_filter_init(gcc_unused const ConfigBlock &block)
 {
-	return new PreparedNormalizeFilter();
+	return std::make_unique<PreparedNormalizeFilter>();
 }
 
 Filter *
@@ -82,8 +82,8 @@ const FilterPlugin normalize_filter_plugin = {
 	normalize_filter_init,
 };
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 normalize_filter_prepare() noexcept
 {
-	return new PreparedNormalizeFilter();
+	return std::make_unique<PreparedNormalizeFilter>();
 }

src/filter/plugins/NormalizeFilterPlugin.hxx

@@ -20,11 +20,13 @@
 #ifndef MPD_NORMALIZE_FILTER_PLUGIN_HXX
 #define MPD_NORMALIZE_FILTER_PLUGIN_HXX
 
+#include <memory>
+
 class PreparedFilter;
 class Filter;
 struct AudioFormat;
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 normalize_filter_prepare() noexcept;
 
 #endif

src/filter/plugins/NullFilterPlugin.cxx

@@ -48,10 +48,10 @@ public:
 	}
 };
 
-static PreparedFilter *
+static std::unique_ptr<PreparedFilter>
 null_filter_init(gcc_unused const ConfigBlock &block)
 {
-	return new PreparedNullFilter();
+	return std::make_unique<PreparedNullFilter>();
 }
 
 const FilterPlugin null_filter_plugin = {

src/filter/plugins/ReplayGainFilterPlugin.cxx

@@ -171,10 +171,10 @@ ReplayGainFilter::Update()
 		pv.SetVolume(volume);
 }
 
-PreparedFilter *
-NewReplayGainFilter(const ReplayGainConfig &config)
+std::unique_ptr<PreparedFilter>
+NewReplayGainFilter(const ReplayGainConfig &config) noexcept
 {
-	return new PreparedReplayGainFilter(config);
+	return std::make_unique<PreparedReplayGainFilter>(config);
 }
 
 Filter *

src/filter/plugins/ReplayGainFilterPlugin.hxx

@@ -22,14 +22,16 @@
 
 #include "ReplayGainMode.hxx"
 
+#include <memory>
+
 class Filter;
 class PreparedFilter;
 class Mixer;
 struct ReplayGainConfig;
 struct ReplayGainInfo;
 
-PreparedFilter *
-NewReplayGainFilter(const ReplayGainConfig &config);
+std::unique_ptr<PreparedFilter>
+NewReplayGainFilter(const ReplayGainConfig &config) noexcept;
 
 /**
  * Enables or disables the hardware mixer for applying replay gain.

src/filter/plugins/RouteFilterPlugin.cxx

@@ -196,10 +196,10 @@ PreparedRouteFilter::PreparedRouteFilter(const ConfigBlock &block)
 	}
 }
 
-static PreparedFilter *
+static std::unique_ptr<PreparedFilter>
 route_filter_init(const ConfigBlock &block)
 {
-	return new PreparedRouteFilter(block);
+	return std::make_unique<PreparedRouteFilter>(block);
 }
 
 RouteFilter::RouteFilter(const AudioFormat &audio_format,

src/filter/plugins/VolumeFilterPlugin.cxx

@@ -65,10 +65,10 @@ VolumeFilter::FilterPCM(ConstBuffer<void> src)
 	return pv.Apply(src);
 }
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 volume_filter_prepare() noexcept
 {
-	return new PreparedVolumeFilter();
+	return std::make_unique<PreparedVolumeFilter>();
 }
 
 unsigned

src/filter/plugins/VolumeFilterPlugin.hxx

@@ -20,10 +20,12 @@
 #ifndef MPD_VOLUME_FILTER_PLUGIN_HXX
 #define MPD_VOLUME_FILTER_PLUGIN_HXX
 
+#include <memory>
+
 class PreparedFilter;
 class Filter;
 
-PreparedFilter *
+std::unique_ptr<PreparedFilter>
 volume_filter_prepare() noexcept;
 
 unsigned