filter/ReplayGain: add ReplayGainConfig copy

Remove dependency on ReplayGain global variables.

src/output/Init.cxx

@@ -205,7 +205,9 @@ AudioOutput::Configure(const ConfigBlock &block)
 }
 
 static void
-audio_output_setup(EventLoop &event_loop, AudioOutput &ao,
+audio_output_setup(EventLoop &event_loop,
+		   const ReplayGainConfig &replay_gain_config,
+		   AudioOutput &ao,
 		   MixerListener &mixer_listener,
 		   const ConfigBlock &block)
 {
@@ -216,12 +218,14 @@ audio_output_setup(EventLoop &event_loop, AudioOutput &ao,
 		block.GetBlockValue("replay_gain_handler", "software");
 
 	if (strcmp(replay_gain_handler, "none") != 0) {
-		ao.prepared_replay_gain_filter = NewReplayGainFilter();
+		ao.prepared_replay_gain_filter =
+			NewReplayGainFilter(replay_gain_config);
 		assert(ao.prepared_replay_gain_filter != nullptr);
 
 		ao.replay_gain_serial = 0;
 
-		ao.prepared_other_replay_gain_filter = NewReplayGainFilter();
+		ao.prepared_other_replay_gain_filter =
+			NewReplayGainFilter(replay_gain_config);
 		assert(ao.prepared_other_replay_gain_filter != nullptr);
 
 		ao.other_replay_gain_serial = 0;
@@ -267,7 +271,9 @@ audio_output_setup(EventLoop &event_loop, AudioOutput &ao,
 }
 
 AudioOutput *
-audio_output_new(EventLoop &event_loop, const ConfigBlock &block,
+audio_output_new(EventLoop &event_loop,
+		 const ReplayGainConfig &replay_gain_config,
+		 const ConfigBlock &block,
 		 MixerListener &mixer_listener,
 		 PlayerControl &pc)
 {
@@ -298,7 +304,8 @@ audio_output_new(EventLoop &event_loop, const ConfigBlock &block,
 	assert(ao != nullptr);
 
 	try {
-		audio_output_setup(event_loop, *ao, mixer_listener, block);
+		audio_output_setup(event_loop, replay_gain_config,
+				   *ao, mixer_listener, block);
 	} catch (...) {
 		ao_plugin_finish(ao);
 		throw;

src/output/Internal.hxx

@@ -40,6 +40,7 @@ struct MusicChunk;
 struct ConfigBlock;
 struct PlayerControl;
 struct AudioOutputPlugin;
+struct ReplayGainConfig;
 
 struct AudioOutput {
 	enum class Command {
@@ -464,7 +465,9 @@ extern struct notify audio_output_client_notify;
  * Throws #std::runtime_error on error.
  */
 AudioOutput *
-audio_output_new(EventLoop &event_loop, const ConfigBlock &block,
+audio_output_new(EventLoop &event_loop,
+		 const ReplayGainConfig &replay_gain_config,
+		 const ConfigBlock &block,
 		 MixerListener &mixer_listener,
 		 PlayerControl &pc);
 

src/output/MultipleOutputs.cxx

@@ -50,10 +50,12 @@ MultipleOutputs::~MultipleOutputs()
 }
 
 static AudioOutput *
-LoadOutput(EventLoop &event_loop, MixerListener &mixer_listener,
+LoadOutput(EventLoop &event_loop,
+	   const ReplayGainConfig &replay_gain_config,
+	   MixerListener &mixer_listener,
 	   PlayerControl &pc, const ConfigBlock &block)
 try {
-	return audio_output_new(event_loop, block,
+	return audio_output_new(event_loop, replay_gain_config, block,
 				mixer_listener,
 				pc);
 } catch (const std::runtime_error &e) {
@@ -65,11 +67,14 @@ try {
 }
 
 void
-MultipleOutputs::Configure(EventLoop &event_loop, PlayerControl &pc)
+MultipleOutputs::Configure(EventLoop &event_loop,
+			   const ReplayGainConfig &replay_gain_config,
+			   PlayerControl &pc)
 {
 	for (const auto *param = config_get_block(ConfigBlockOption::AUDIO_OUTPUT);
 	     param != nullptr; param = param->next) {
-		auto output = LoadOutput(event_loop, mixer_listener,
+		auto output = LoadOutput(event_loop, replay_gain_config,
+					 mixer_listener,
 					 pc, *param);
 		if (FindByName(output->name) != nullptr)
 			throw FormatRuntimeError("output devices with identical "
@@ -81,7 +86,8 @@ MultipleOutputs::Configure(EventLoop &event_loop, PlayerControl &pc)
 	if (outputs.empty()) {
 		/* auto-detect device */
 		const ConfigBlock empty;
-		auto output = LoadOutput(event_loop, mixer_listener,
+		auto output = LoadOutput(event_loop, replay_gain_config,
+					 mixer_listener,
 					 pc, empty);
 		outputs.push_back(output);
 	}

src/output/MultipleOutputs.hxx

@@ -42,6 +42,7 @@ class MixerListener;
 struct MusicChunk;
 struct PlayerControl;
 struct AudioOutput;
+struct ReplayGainConfig;
 
 class MultipleOutputs {
 	MixerListener &mixer_listener;
@@ -75,7 +76,9 @@ public:
 	MultipleOutputs(MixerListener &_mixer_listener);
 	~MultipleOutputs();
 
-	void Configure(EventLoop &event_loop, PlayerControl &pc);
+	void Configure(EventLoop &event_loop,
+		       const ReplayGainConfig &replay_gain_config,
+		       PlayerControl &pc);
 
 	/**
 	 * Returns the total number of audio output devices, including