audio_core: Implement Sink and SinkStream interfaces with cubeb.

1 files changed, 190 insertions, 0 deletions

diff --git a/src/audio_core/cubeb_sink.cpp b/src/audio_core/cubeb_sink.cpp
new file mode 100644
index 000000000..34ae5b062
--- /dev/null
+++ b/src/audio_core/cubeb_sink.cpp
@@ -0,0 +1,190 @@
+// Copyright 2018 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <algorithm>
+#include <cstring>
+
+#include "audio_core/cubeb_sink.h"
+#include "audio_core/stream.h"
+#include "common/logging/log.h"
+
+namespace AudioCore {
+
+class SinkStreamImpl final : public SinkStream {
+public:
+    SinkStreamImpl(cubeb* ctx, cubeb_devid output_device) : ctx{ctx} {
+        cubeb_stream_params params;
+        params.rate = 48000;
+        params.channels = GetNumChannels();
+        params.format = CUBEB_SAMPLE_S16NE;
+        params.layout = CUBEB_LAYOUT_STEREO;
+
+        u32 minimum_latency = 0;
+        if (cubeb_get_min_latency(ctx, &params, &minimum_latency) != CUBEB_OK) {
+            LOG_CRITICAL(Audio_Sink, "Error getting minimum latency");
+        }
+
+        if (cubeb_stream_init(ctx, &stream_backend, "yuzu Audio Output", nullptr, nullptr,
+                              output_device, &params, std::max(512u, minimum_latency),
+                              &SinkStreamImpl::DataCallback, &SinkStreamImpl::StateCallback,
+                              this) != CUBEB_OK) {
+            LOG_CRITICAL(Audio_Sink, "Error initializing cubeb stream");
+            return;
+        }
+
+        if (cubeb_stream_start(stream_backend) != CUBEB_OK) {
+            LOG_CRITICAL(Audio_Sink, "Error starting cubeb stream");
+            return;
+        }
+    }
+
+    ~SinkStreamImpl() {
+        if (!ctx) {
+            return;
+        }
+
+        if (cubeb_stream_stop(stream_backend) != CUBEB_OK) {
+            LOG_CRITICAL(Audio_Sink, "Error stopping cubeb stream");
+        }
+
+        cubeb_stream_destroy(stream_backend);
+    }
+
+    void EnqueueSamples(u32 num_channels, const s16* samples, size_t sample_count) override {
+        if (!ctx) {
+            return;
+        }
+
+        queue.reserve(queue.size() + sample_count * GetNumChannels());
+
+        if (num_channels == 2) {
+            // Copy as-is
+            std::copy(samples, samples + sample_count * GetNumChannels(),
+                      std::back_inserter(queue));
+        } else if (num_channels == 6) {
+            // Downsample 6 channels to 2
+            const size_t sample_count_copy_size = sample_count * num_channels * 2;
+            queue.reserve(sample_count_copy_size);
+            for (size_t i = 0; i < sample_count * num_channels; i += num_channels) {
+                queue.push_back(samples[i]);
+                queue.push_back(samples[i + 1]);
+            }
+        } else {
+            ASSERT_MSG(false, "Unimplemented");
+        }
+    }
+
+    u32 GetNumChannels() const {
+        // Only support 2-channel stereo output for now
+        return 2;
+    }
+
+private:
+    std::vector<std::string> device_list;
+
+    cubeb* ctx{};
+    cubeb_stream* stream_backend{};
+
+    std::vector<s16> queue;
+
+    static long DataCallback(cubeb_stream* stream, void* user_data, const void* input_buffer,
+                             void* output_buffer, long num_frames);
+    static void StateCallback(cubeb_stream* stream, void* user_data, cubeb_state state);
+};
+
+CubebSink::CubebSink(std::string target_device_name) {
+    if (cubeb_init(&ctx, "yuzu", nullptr) != CUBEB_OK) {
+        LOG_CRITICAL(Audio_Sink, "cubeb_init failed");
+        return;
+    }
+
+    if (target_device_name != auto_device_name && !target_device_name.empty()) {
+        cubeb_device_collection collection;
+        if (cubeb_enumerate_devices(ctx, CUBEB_DEVICE_TYPE_OUTPUT, &collection) != CUBEB_OK) {
+            LOG_WARNING(Audio_Sink, "Audio output device enumeration not supported");
+        } else {
+            const auto collection_end{collection.device + collection.count};
+            const auto device{std::find_if(collection.device, collection_end,
+                                           [&](const cubeb_device_info& device) {
+                                               return target_device_name == device.friendly_name;
+                                           })};
+            if (device != collection_end) {
+                output_device = device->devid;
+            }
+            cubeb_device_collection_destroy(ctx, &collection);
+        }
+    }
+}
+
+CubebSink::~CubebSink() {
+    if (!ctx) {
+        return;
+    }
+
+    for (auto& sink_stream : sink_streams) {
+        sink_stream.reset();
+    }
+
+    cubeb_destroy(ctx);
+}
+
+SinkStream& CubebSink::AcquireSinkStream(u32 sample_rate, u32 num_channels) {
+    sink_streams.push_back(std::make_unique<SinkStreamImpl>(ctx, output_device));
+    return *sink_streams.back();
+}
+
+long SinkStreamImpl::DataCallback(cubeb_stream* stream, void* user_data, const void* input_buffer,
+                                  void* output_buffer, long num_frames) {
+    SinkStreamImpl* impl = static_cast<SinkStreamImpl*>(user_data);
+    u8* buffer = reinterpret_cast<u8*>(output_buffer);
+
+    if (!impl) {
+        return {};
+    }
+
+    const size_t frames_to_write{
+        std::min(impl->queue.size() / impl->GetNumChannels(), static_cast<size_t>(num_frames))};
+
+    memcpy(buffer, impl->queue.data(), frames_to_write * sizeof(s16) * impl->GetNumChannels());
+    impl->queue.erase(impl->queue.begin(),
+                      impl->queue.begin() + frames_to_write * impl->GetNumChannels());
+
+    if (frames_to_write < num_frames) {
+        // Fill the rest of the frames with silence
+        memset(buffer + frames_to_write * sizeof(s16) * impl->GetNumChannels(), 0,
+               (num_frames - frames_to_write) * sizeof(s16) * impl->GetNumChannels());
+    }
+
+    return num_frames;
+}
+
+void SinkStreamImpl::StateCallback(cubeb_stream* stream, void* user_data, cubeb_state state) {}
+
+std::vector<std::string> ListCubebSinkDevices() {
+    std::vector<std::string> device_list;
+    cubeb* ctx;
+
+    if (cubeb_init(&ctx, "Citra Device Enumerator", nullptr) != CUBEB_OK) {
+        LOG_CRITICAL(Audio_Sink, "cubeb_init failed");
+        return {};
+    }
+
+    cubeb_device_collection collection;
+    if (cubeb_enumerate_devices(ctx, CUBEB_DEVICE_TYPE_OUTPUT, &collection) != CUBEB_OK) {
+        LOG_WARNING(Audio_Sink, "Audio output device enumeration not supported");
+    } else {
+        for (size_t i = 0; i < collection.count; i++) {
+            const cubeb_device_info& device = collection.device[i];
+            if (device.friendly_name) {
+                device_list.emplace_back(device.friendly_name);
+            }
+        }
+        cubeb_device_collection_destroy(ctx, &collection);
+    }
+
+    cubeb_destroy(ctx);
+    return device_list;
+}
+
+} // namespace AudioCore