Use an intermediate buffer for writing to the ringbuffer

It doesn't seem as though AudioUnitRender likes being given two buffers to
render/capture samples into segmented memory.

1 files changed, 11 insertions, 26 deletions

diff --git a/alc/backends/coreaudio.cpp b/alc/backends/coreaudio.cpp
index 71b57fde..f4190533 100644
--- a/alc/backends/coreaudio.cpp
+++ b/alc/backends/coreaudio.cpp
@@ -548,6 +548,8 @@ struct CoreAudioCapture final : public BackendBase {
 
     SampleConverterPtr mConverter;
 
+    al::vector<char> mCaptureData;
+
     RingBufferPtr mRing{nullptr};
 
     DEF_NEWDEL(CoreAudioCapture)
@@ -566,43 +568,24 @@ OSStatus CoreAudioCapture::RecordProc(AudioUnitRenderActionFlags *ioActionFlags,
     AudioBufferList*) noexcept
 {
     union {
-        al::byte _[sizeof(AudioBufferList) + sizeof(AudioBuffer)*2];
+        al::byte _[maxz(sizeof(AudioBufferList), offsetof(AudioBufferList, mBuffers[1]))];
         AudioBufferList list;
     } audiobuf{};
 
-    auto rec_vec = mRing->getWriteVector();
-    inNumberFrames = static_cast<UInt32>(minz(inNumberFrames,
-        rec_vec.first.len+rec_vec.second.len));
+    audiobuf.list.mNumberBuffers = 1;
+    audiobuf.list.mBuffers[0].mNumberChannels = mFormat.mChannelsPerFrame;
+    audiobuf.list.mBuffers[0].mData = mCaptureData.data();
+    audiobuf.list.mBuffers[0].mDataByteSize = static_cast<UInt32>(mCaptureData.size());
 
-    // Fill the ringbuffer's two segments with data from the input device
-    if(rec_vec.first.len >= inNumberFrames)
-    {
-        audiobuf.list.mNumberBuffers = 1;
-        audiobuf.list.mBuffers[0].mNumberChannels = mFormat.mChannelsPerFrame;
-        audiobuf.list.mBuffers[0].mData = rec_vec.first.buf;
-        audiobuf.list.mBuffers[0].mDataByteSize = inNumberFrames * mFormat.mBytesPerFrame;
-    }
-    else
-    {
-        const auto remaining = static_cast<uint>(inNumberFrames - rec_vec.first.len);
-        audiobuf.list.mNumberBuffers = 2;
-        audiobuf.list.mBuffers[0].mNumberChannels = mFormat.mChannelsPerFrame;
-        audiobuf.list.mBuffers[0].mData = rec_vec.first.buf;
-        audiobuf.list.mBuffers[0].mDataByteSize = static_cast<UInt32>(rec_vec.first.len) *
-            mFormat.mBytesPerFrame;
-        audiobuf.list.mBuffers[1].mNumberChannels = mFormat.mChannelsPerFrame;
-        audiobuf.list.mBuffers[1].mData = rec_vec.second.buf;
-        audiobuf.list.mBuffers[1].mDataByteSize = remaining * mFormat.mBytesPerFrame;
-    }
     OSStatus err{AudioUnitRender(mAudioUnit, ioActionFlags, inTimeStamp, inBusNumber,
         inNumberFrames, &audiobuf.list)};
     if(err != noErr)
     {
-        ERR("AudioUnitRender error: %d\n", err);
+        ERR("AudioUnitRender capture error: %d\n", err);
         return err;
     }
 
-    mRing->writeAdvance(inNumberFrames);
+    mRing->write(mCaptureData.data(), inNumberFrames * mFrameSize);
     return noErr;
 }
 
@@ -814,6 +797,8 @@ void CoreAudioCapture::open(const char *name)
         throw al::backend_exception{al::backend_error::DeviceError,
             "Could not get input frame count: %u", err};
 
+    mCaptureData.resize(outputFrameCount * mFrameSize);
+
     outputFrameCount = static_cast<UInt32>(maxu64(outputFrameCount, FrameCount64));
     mRing = RingBuffer::Create(outputFrameCount, mFrameSize, false);