From 105a72457ec1c5bf7c0ddc3b58e8b52141966237 Mon Sep 17 00:00:00 2001
From: casey langen <casey.langen@gmail.com>
Date: Sun, 25 Dec 2016 11:06:23 -0800
Subject: [PATCH] Sane implementation of DirectSoundOut::Drain() -- just write
 silence to the playback buffer until it's full.

---
 src/contrib/directsoundout/DirectSoundOut.cpp | 65 +++++++++++++++----
 src/core/audio/GaplessTransport.cpp           | 11 +---
 2 files changed, 53 insertions(+), 23 deletions(-)

diff --git a/src/contrib/directsoundout/DirectSoundOut.cpp b/src/contrib/directsoundout/DirectSoundOut.cpp
index 1c4f32a0f..8f7b5c112 100644
--- a/src/contrib/directsoundout/DirectSoundOut.cpp
+++ b/src/contrib/directsoundout/DirectSoundOut.cpp
@@ -41,6 +41,41 @@
 #include <chrono>
 #include <thread>
 
+class DrainBuffer :
+    public musik::core::sdk::IBuffer,
+    public musik::core::sdk::IBufferProvider
+{
+    public:
+        DrainBuffer() {
+            this->buffer = nullptr;
+            this->channels = this->samples = this->rate = 0;
+        }
+
+        virtual ~DrainBuffer() {
+            delete[] buffer;
+        }
+
+        void Init() {
+            delete[] buffer;
+            this->buffer = new float[this->samples];
+            memset(this->buffer, 0, this->Bytes());
+        }
+
+        virtual long SampleRate() const { return this->rate; }
+        virtual void SetSampleRate(long sampleRate) { this->rate = sampleRate; }
+        virtual int Channels() const { return this->channels; }
+        virtual void SetChannels(int channels) { this->channels = channels; }
+        virtual float* BufferPointer() const { return this->buffer; }
+        virtual long Samples() const { return this->samples; }
+        virtual void SetSamples(long samples) { this->samples = samples; }
+        virtual long Bytes() const { return this->samples * sizeof(float); }
+        virtual void OnBufferProcessed(IBuffer *buffer) { }
+
+    private:
+        int channels, samples, rate;
+        float *buffer;
+};
+
 #define MAX_BUFFERS_PER_OUTPUT 8
 
 #define BUFFER_SIZE_BYTES_PER_CHANNEL \
@@ -228,6 +263,8 @@ bool DirectSoundOut::Play(IBuffer *buffer, IBufferProvider *provider) {
 }
 
 void DirectSoundOut::Drain() {
+    static const int drainCount = 4;
+
     int channels = this->channels;
     int rate = this->rate;
     int bufferSize = this->bufferSize;
@@ -236,22 +273,24 @@ void DirectSoundOut::Drain() {
         return;
     }
 
-    int sleepMs = 0;
+    int totalSamples = bufferSize / sizeof(float) / channels;
 
-    if (this->state != StateStopped) {
-        Lock lock(this->stateMutex);
+    DrainBuffer buffer;
+    buffer.SetChannels(channels);
+    buffer.SetSampleRate(rate);
+    buffer.SetSamples(totalSamples / drainCount);
+    buffer.Init();
 
-        if (this->secondaryBuffer) {
-            int pendingBytes = this->bufferSize - getAvailableBytes(
-                this->secondaryBuffer, this->writeOffset, this->bufferSize);
-
-            int samples = pendingBytes / sizeof(float) / channels;
-            sleepMs = ((long long)(samples * 1000) / rate);
+    /* fill the rest of the buffer with silence to ensure all
+    real samples get played! */
+    int count = drainCount + 1;
+    while (count > 0 && this->state != StateStopped) {
+        if (!this->Play(&buffer, &buffer)) {
+            Sleep(250); /* eh */
+        }
+        else {
+            --count;
         }
-    }
-
-    if (sleepMs > 0) {
-        Sleep(sleepMs);
     }
 
     this->Stop();
diff --git a/src/core/audio/GaplessTransport.cpp b/src/core/audio/GaplessTransport.cpp
index cd02820f9..b90d7394d 100644
--- a/src/core/audio/GaplessTransport.cpp
+++ b/src/core/audio/GaplessTransport.cpp
@@ -328,17 +328,8 @@ void GaplessTransport::OnPlayerFinished(Player* player) {
         }
     }
 
-    /* note we could also call this->Stop() here, but it will shut down the
-    output and drain any pending buffers. this is a bit of extra overhead
-    that isn't necessary. */
     if (stopped) {
-        {
-            LockT lock(this->stateMutex);
-            RESET_NEXT_PLAYER(this);
-            RESET_ACTIVE_PLAYER(this);
-        }
-
-        this->SetPlaybackState(PlaybackStopped);
+        this->Stop();
     }
 }