1 files changed, 151 insertions, 0 deletions
diff --git a/src/output/Filtered.cxx b/src/output/Filtered.cxx
new file mode 100644
index 000000000..db74a3ab5
--- /dev/null
+++ b/src/output/Filtered.cxx
@@ -0,0 +1,151 @@
+/*
+ * Copyright 2003-2017 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "Filtered.hxx"
+#include "OutputPlugin.hxx"
+#include "Domain.hxx"
+#include "Log.hxx"
+#include "mixer/MixerInternal.hxx"
+#include "mixer/plugins/SoftwareMixerPlugin.hxx"
+#include "filter/plugins/ConvertFilterPlugin.hxx"
+#include "util/RuntimeError.hxx"
+#include "util/StringBuffer.hxx"
+
+void
+FilteredAudioOutput::Enable()
+{
+	try {
+		ao_plugin_enable(*this);
+	} catch (const std::runtime_error &e) {
+		std::throw_with_nested(FormatRuntimeError("Failed to enable output \"%s\" [%s]",
+							  name, plugin.name));
+	}
+}
+
+void
+FilteredAudioOutput::Disable() noexcept
+{
+	ao_plugin_disable(*this);
+}
+
+void
+FilteredAudioOutput::ConfigureConvertFilter()
+{
+	try {
+		convert_filter_set(convert_filter.Get(), out_audio_format);
+	} catch (const std::runtime_error &e) {
+		std::throw_with_nested(FormatRuntimeError("Failed to convert for \"%s\" [%s]",
+							  name, plugin.name));
+	}
+}
+
+void
+FilteredAudioOutput::OpenOutputAndConvert(AudioFormat desired_audio_format)
+{
+	out_audio_format = desired_audio_format;
+
+	try {
+		ao_plugin_open(*this, out_audio_format);
+	} catch (const std::runtime_error &e) {
+		std::throw_with_nested(FormatRuntimeError("Failed to open \"%s\" [%s]",
+							  name, plugin.name));
+	}
+
+	FormatDebug(output_domain,
+		    "opened plugin=%s name=\"%s\" audio_format=%s",
+		    plugin.name, name,
+		    ToString(out_audio_format).c_str());
+
+	try {
+		ConfigureConvertFilter();
+	} catch (const std::runtime_error &e) {
+		ao_plugin_close(*this);
+
+		if (out_audio_format.format == SampleFormat::DSD) {
+			/* if the audio output supports DSD, but not
+			   the given sample rate, it asks MPD to
+			   resample; resampling DSD however is not
+			   implemented; our last resort is to give up
+			   DSD and fall back to PCM */
+
+			LogError(e);
+			FormatError(output_domain, "Retrying without DSD");
+
+			desired_audio_format.format = SampleFormat::FLOAT;
+			OpenOutputAndConvert(desired_audio_format);
+			return;
+		}
+
+		throw;
+	}
+}
+
+void
+FilteredAudioOutput::CloseOutput(bool drain) noexcept
+{
+	if (drain)
+		ao_plugin_drain(*this);
+	else
+		ao_plugin_cancel(*this);
+
+	ao_plugin_close(*this);
+}
+
+void
+FilteredAudioOutput::OpenSoftwareMixer() noexcept
+{
+	if (mixer != nullptr && mixer->IsPlugin(software_mixer_plugin))
+		software_mixer_set_filter(*mixer, volume_filter.Get());
+}
+
+void
+FilteredAudioOutput::CloseSoftwareMixer() noexcept
+{
+	if (mixer != nullptr && mixer->IsPlugin(software_mixer_plugin))
+		software_mixer_set_filter(*mixer, nullptr);
+}
+
+void
+FilteredAudioOutput::Close(bool drain) noexcept
+{
+	CloseOutput(drain);
+	CloseSoftwareMixer();
+
+	FormatDebug(output_domain, "closed plugin=%s name=\"%s\"",
+		    plugin.name, name);
+}
+
+void
+FilteredAudioOutput::BeginPause() noexcept
+{
+	ao_plugin_cancel(*this);
+}
+
+bool
+FilteredAudioOutput::IteratePause() noexcept
+{
+	try {
+		return ao_plugin_pause(*this);
+	} catch (const std::runtime_error &e) {
+		FormatError(e, "\"%s\" [%s] failed to pause",
+			    name, plugin.name);
+		return false;
+	}
+}