Add AudioBackend::device_output_channels().

3 files changed, 33 insertions, 22 deletions

diff --git a/src/wx/audio_backend.cc b/src/wx/audio_backend.cc
index 3cb2b8d4f..9c8b1c386 100644
--- a/src/wx/audio_backend.cc
+++ b/src/wx/audio_backend.cc
@@ -24,6 +24,9 @@
 
 using std::string;
 using std::vector;
+using boost::optional;
+
+
 AudioBackend* AudioBackend::_instance = nullptr;
 
 
@@ -122,6 +125,33 @@ AudioBackend::default_device_name()
 }
 
 
+optional<int>
+AudioBackend::device_output_channels(string name)
+{
+#if (RTAUDIO_VERSION_MAJOR >= 6)
+	for (auto device_id: _rtaudio.getDeviceIds()) {
+		auto info = audio.getDeviceInfo(device_id);
+		if (info.name == name) {
+			return info.outputChannels;
+		}
+	}
+#else
+	for (unsigned int i = 0; i < _rtaudio.getDeviceCount(); ++i) {
+		try {
+			auto info = _rtaudio.getDeviceInfo(i);
+			if (info.name == name) {
+				return info.outputChannels;
+			}
+		} catch (RtAudioError&) {
+			/* Never mind */
+		}
+	}
+#endif
+
+	return {};
+}
+
+
 void
 AudioBackend::abort_stream_if_running()
 {
diff --git a/src/wx/audio_backend.h b/src/wx/audio_backend.h
index f2a44a5fb..aa4adf13c 100644
--- a/src/wx/audio_backend.h
+++ b/src/wx/audio_backend.h
@@ -41,6 +41,8 @@ public:
 
 	std::vector<std::string> output_device_names();
 	boost::optional<std::string> default_device_name();
+	boost::optional<int> device_output_channels(std::string name);
+
 	void abort_stream_if_running();
 	boost::optional<std::string> start_stream();
 
diff --git a/src/wx/config_dialog.cc b/src/wx/config_dialog.cc
index d97eeecc5..12e914742 100644
--- a/src/wx/config_dialog.cc
+++ b/src/wx/config_dialog.cc
@@ -964,28 +964,7 @@ SoundPage::config_changed ()
 	apis[RtAudio::LINUX_OSS]      = _("OSS");
 	apis[RtAudio::RTAUDIO_DUMMY]  = _("Dummy");
 
-	int channels = 0;
-	if (configured_so) {
-#if (RTAUDIO_VERSION_MAJOR >= 6)
-		for (auto device_id: audio.getDeviceIds()) {
-			auto info = audio.getDeviceInfo(device_id);
-			if (info.name == *configured_so && info.outputChannels > 0) {
-				channels = info.outputChannels;
-			}
-		}
-#else
-		for (unsigned int i = 0; i < audio.getDeviceCount(); ++i) {
-			try {
-				auto info = audio.getDeviceInfo(i);
-				if (info.name == *configured_so && info.outputChannels > 0) {
-					channels = info.outputChannels;
-				}
-			} catch (RtAudioError&) {
-				/* Never mind */
-			}
-		}
-#endif
-	}
+	int const channels = configured_so ? AudioBackend::instance()->device_output_channels(*configured_so).get_value_or(0) : 0;
 
 	_sound_output_details->SetLabel (
 		wxString::Format(_("%d channels on %s"), channels, apis[audio.getCurrentApi()])