Pre-test opening a stream for audio backends, fall back to null if not suitable.

src/audio_core/sink/cubeb_sink.cpp

@@ -8,6 +8,7 @@
 #include "audio_core/sink/cubeb_sink.h"
 #include "audio_core/sink/sink_stream.h"
 #include "common/logging/log.h"
+#include "common/scope_exit.h"
 #include "core/core.h"
 
 #ifdef _WIN32
@@ -332,25 +333,38 @@ std::vector<std::string> ListCubebSinkDevices(bool capture) {
     return device_list;
 }
 
-u32 GetCubebLatency() {
+namespace {
-    cubeb* ctx;
+static long TmpDataCallback(cubeb_stream*, void*, const void*, void*, long) {
+    return TargetSampleCount;
+}
+static void TmpStateCallback(cubeb_stream*, void*, cubeb_state) {}
+} // namespace
+
+bool IsCubebSuitable() {
+#if !defined(HAVE_CUBEB)
+    return false;
+#else
+    cubeb* ctx{nullptr};
 
 #ifdef _WIN32
     auto com_init_result = CoInitializeEx(nullptr, COINIT_MULTITHREADED);
 #endif
 
+    // Init cubeb
     if (cubeb_init(&ctx, "yuzu Latency Getter", nullptr) != CUBEB_OK) {
-        LOG_CRITICAL(Audio_Sink, "cubeb_init failed");
+        LOG_ERROR(Audio_Sink, "Cubeb failed to init, it is not suitable.");
-        // Return a large latency so we choose SDL instead.
+        return false;
-        return 10000u;
     }
 
+    SCOPE_EXIT({ cubeb_destroy(ctx); });
+
 #ifdef _WIN32
     if (SUCCEEDED(com_init_result)) {
         CoUninitialize();
     }
 #endif
 
+    // Test min latency
     cubeb_stream_params params{};
     params.rate = TargetSampleRate;
     params.channels = 2;
@@ -361,12 +375,32 @@ u32 GetCubebLatency() {
     u32 latency{0};
     const auto latency_error = cubeb_get_min_latency(ctx, &params, &latency);
     if (latency_error != CUBEB_OK) {
-        LOG_CRITICAL(Audio_Sink, "Error getting minimum latency, error: {}", latency_error);
+        LOG_ERROR(Audio_Sink, "Cubeb could not get min latency, it is not suitable.");
-        latency = TargetSampleCount * 2;
+        return false;
     }
     latency = std::max(latency, TargetSampleCount * 2);
-    cubeb_destroy(ctx);
+
-    return latency;
+    if (latency > TargetSampleCount * 3) {
+        LOG_ERROR(Audio_Sink, "Cubeb latency is too high, it is not suitable.");
+        return false;
+    }
+
+    // Test opening a device with standard parameters
+    cubeb_devid output_device{0};
+    cubeb_devid input_device{0};
+    std::string name{"Yuzu test"};
+    cubeb_stream* stream{nullptr};
+
+    if (cubeb_stream_init(ctx, &stream, name.c_str(), input_device, nullptr, output_device, &params,
+                          latency, &TmpDataCallback, &TmpStateCallback, nullptr) != CUBEB_OK) {
+        LOG_CRITICAL(Audio_Sink, "Cubeb could not open a device, it is not suitable.");
+        return false;
+    }
+
+    cubeb_stream_stop(stream);
+    cubeb_stream_destroy(stream);
+    return true;
+#endif
 }
 
 } // namespace AudioCore::Sink

src/audio_core/sink/cubeb_sink.h

@@ -97,10 +97,11 @@ private:
 std::vector<std::string> ListCubebSinkDevices(bool capture);
 
 /**
- * Get the reported latency for this sink.
+ * Check if this backend is suitable for use.
+ * Checks if enabled, its latency, whether it opens successfully, etc.
  *
- * @return Minimum latency for this sink.
+ * @return True is this backend is suitable, false otherwise.
  */
-u32 GetCubebLatency();
+bool IsCubebSuitable();
 
 } // namespace AudioCore::Sink

src/audio_core/sink/sdl2_sink.cpp

@@ -9,6 +9,7 @@
 #include "audio_core/sink/sdl2_sink.h"
 #include "audio_core/sink/sink_stream.h"
 #include "common/logging/log.h"
+#include "common/scope_exit.h"
 #include "core/core.h"
 
 namespace AudioCore::Sink {
@@ -84,6 +85,7 @@ public:
         }
 
         Stop();
+        SDL_ClearQueuedAudio(device);
         SDL_CloseAudioDevice(device);
     }
 
@@ -227,8 +229,42 @@ std::vector<std::string> ListSDLSinkDevices(bool capture) {
     return device_list;
 }
 
-u32 GetSDLLatency() {
+bool IsSDLSuitable() {
-    return TargetSampleCount * 2;
+#if !defined(HAVE_SDL2)
+    return false;
+#else
+    // Check SDL can init
+    if (!SDL_WasInit(SDL_INIT_AUDIO)) {
+        if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) {
+            LOG_ERROR(Audio_Sink, "SDL failed to init, it is not suitable. Error: {}",
+                      SDL_GetError());
+            return false;
+        }
+    }
+
+    // We can set any latency frequency we want with SDL, so no need to check that.
+
+    // Check we can open a device with standard parameters
+    SDL_AudioSpec spec;
+    spec.freq = TargetSampleRate;
+    spec.channels = 2u;
+    spec.format = AUDIO_S16SYS;
+    spec.samples = TargetSampleCount * 2;
+    spec.callback = nullptr;
+    spec.userdata = nullptr;
+
+    SDL_AudioSpec obtained;
+    auto device = SDL_OpenAudioDevice(nullptr, false, &spec, &obtained, false);
+
+    if (device == 0) {
+        LOG_ERROR(Audio_Sink, "SDL failed to open a device, it is not suitable. Error: {}",
+                  SDL_GetError());
+        return false;
+    }
+
+    SDL_CloseAudioDevice(device);
+    return true;
+#endif
 }
 
 } // namespace AudioCore::Sink

src/audio_core/sink/sdl2_sink.h

@@ -88,10 +88,11 @@ private:
 std::vector<std::string> ListSDLSinkDevices(bool capture);
 
 /**
- * Get the reported latency for this sink.
+ * Check if this backend is suitable for use.
+ * Checks if enabled, its latency, whether it opens successfully, etc.
  *
- * @return Minimum latency for this sink.
+ * @return True is this backend is suitable, false otherwise.
  */
-u32 GetSDLLatency();
+bool IsSDLSuitable();
 
 } // namespace AudioCore::Sink

src/audio_core/sink/sink_details.cpp

@@ -22,7 +22,7 @@ namespace {
 struct SinkDetails {
     using FactoryFn = std::unique_ptr<Sink> (*)(std::string_view);
     using ListDevicesFn = std::vector<std::string> (*)(bool);
-    using LatencyFn = u32 (*)();
+    using SuitableFn = bool (*)();
 
     /// Name for this sink.
     Settings::AudioEngine id;
@@ -30,8 +30,8 @@ struct SinkDetails {
     FactoryFn factory;
     /// A method to call to list available devices.
     ListDevicesFn list_devices;
-    /// Method to get the latency of this backend.
+    /// Check whether this backend is suitable to be used.
-    LatencyFn latency;
+    SuitableFn is_suitable;
 };
 
 // sink_details is ordered in terms of desirability, with the best choice at the top.
@@ -43,7 +43,7 @@ constexpr SinkDetails sink_details[] = {
             return std::make_unique<CubebSink>(device_id);
         },
         &ListCubebSinkDevices,
-        &GetCubebLatency,
+        &IsCubebSuitable,
     },
 #endif
 #ifdef HAVE_SDL2
@@ -53,14 +53,17 @@ constexpr SinkDetails sink_details[] = {
             return std::make_unique<SDLSink>(device_id);
         },
         &ListSDLSinkDevices,
-        &GetSDLLatency,
+        &IsSDLSuitable,
     },
 #endif
-    SinkDetails{Settings::AudioEngine::Null,
+    SinkDetails{
-                [](std::string_view device_id) -> std::unique_ptr<Sink> {
+        Settings::AudioEngine::Null,
-                    return std::make_unique<NullSink>(device_id);
+        [](std::string_view device_id) -> std::unique_ptr<Sink> {
-                },
+            return std::make_unique<NullSink>(device_id);
-                [](bool capture) { return std::vector<std::string>{"null"}; }, []() { return 0u; }},
+        },
+        [](bool capture) { return std::vector<std::string>{"null"}; },
+        []() { return true; },
+    },
 };
 
 const SinkDetails& GetOutputSinkDetails(Settings::AudioEngine sink_id) {
@@ -72,18 +75,22 @@ const SinkDetails& GetOutputSinkDetails(Settings::AudioEngine sink_id) {
     auto iter = find_backend(sink_id);
 
     if (sink_id == Settings::AudioEngine::Auto) {
-        // Auto-select a backend. Prefer CubeB, but it may report a large minimum latency which
+        // Auto-select a backend. Use the sink details ordering, preferring cubeb first, checking
-        // causes audio issues, in that case go with SDL.
+        // that the backend is available and suitable to use.
-#if defined(HAVE_CUBEB) && defined(HAVE_SDL2)
+        for (auto& details : sink_details) {
-        iter = find_backend(Settings::AudioEngine::Cubeb);
+            if (details.is_suitable()) {
-        if (iter->latency() > TargetSampleCount * 3) {
+                iter = &details;
-            iter = find_backend(Settings::AudioEngine::Sdl2);
+                break;
+            }
+        }
+        LOG_ERROR(Service_Audio, "Auto-selecting the {} backend",
+                  Settings::CanonicalizeEnum(iter->id));
+    } else {
+        if (iter != std::end(sink_details) && !iter->is_suitable()) {
+            LOG_ERROR(Service_Audio, "Selected backend {} is not suitable, falling back to null",
+                      Settings::CanonicalizeEnum(iter->id));
+            iter = find_backend(Settings::AudioEngine::Null);
         }
-#else
-        iter = std::begin(sink_details);
-#endif
-        LOG_INFO(Service_Audio, "Auto-selecting the {} backend",
-                 Settings::CanonicalizeEnum(iter->id));
     }
 
     if (iter == std::end(sink_details)) {