T12: native audio loop SPSC + WASAPI (exclusive/shared, zero-lock audio thread, SendNote -> SPSC)

native_host/VST2AudioEngine.cpp

@@ -23,6 +23,9 @@
 #include <vector>
 
 #include "vestige.h"
+#include "AudioEngine.h"
+
+#include <atomic>
 
 namespace {
 
@@ -45,6 +48,8 @@ struct Instance
     int32 handle = 0;
     SF_ParamChangedCallback paramCb = nullptr;
     void* paramCbUserdata = nullptr;
+    sonicforge::AudioEngine audio; // T12: native audio loop (SPSC + WASAPI)
+    std::atomic<bool> audioRunning {false};
 };
 
 std::mutex g_mutex;
@@ -116,6 +121,53 @@ VstIntPtr VSTCALLBACK hostAudioMasterImpl (AEffect* effect, int32 opcode, int32
     }
 }
 
+// T12: audio thread callback — effProcessEvents (MIDI drain tu SPSC) +
+// processReplacing. Chay tren WASAPI render thread: KHONG lock, KHONG cap phat.
+bool vst2AudioProcess (const sonicforge::MidiEvent* events, int32 eventCount,
+                       float* outL, float* outR, int32 frames, void* userdata)
+{
+    Instance* inst = static_cast<Instance*> (userdata);
+    if (!inst || !inst->effect)
+        return false;
+
+    if (eventCount > 0)
+    {
+        int32 n = eventCount < 256 ? eventCount : 256;
+        VstMidiEvent midi[256];
+        VstEvent* ptrs[256];
+        struct VstEventsBuf { int32 numEvents; intptr_t reserved; VstEvent* events[256]; };
+        VstEventsBuf buf = {};
+        buf.numEvents = n;
+        for (int32 i = 0; i < n; ++i)
+        {
+            VstMidiEvent& m = midi[i];
+            std::memset (&m, 0, sizeof (m));
+            m.type = kVstMidiType;
+            m.byteSize = static_cast<int32> (sizeof (VstMidiEvent));
+            m.deltaFrames = 0;
+            m.flags = kVstMidiEventIsRealtime;
+            m.midiData[0] = static_cast<char> ((events[i].noteOn ? 0x90 : 0x80) |
+                                               (events[i].channel & 0x0F));
+            m.midiData[1] = static_cast<char> (events[i].pitch & 0x7F);
+            m.midiData[2] = events[i].noteOn
+                ? static_cast<char> (static_cast<int> (events[i].velocity * 127.0f) & 0x7F)
+                : 0;
+            ptrs[i] = reinterpret_cast<VstEvent*> (&m);
+            buf.events[i] = ptrs[i];
+        }
+        inst->effect->dispatcher (inst->effect, effProcessEvents, 0, 0,
+                                  reinterpret_cast<VstEvents*> (&buf), 0.0f);
+    }
+
+    if (inst->effect->processReplacing)
+    {
+        float* outs[2] = { outL, outR };
+        inst->effect->processReplacing (inst->effect, nullptr, outs, frames);
+        return true;
+    }
+    return false;
+}
+
 } // namespace
 
 extern "C" {
@@ -244,6 +296,9 @@ __declspec (dllexport) int32 SF_VST2_Close (int32 handle, char* err, int32 err_c
         return -1;
     }
     Instance* inst = it->second.get ();
+    // T12: dung audio loop (join render thread) truoc khi pha huy plugin.
+    inst->audioRunning.store (false, std::memory_order_release);
+    inst->audio.stop ();
     if (inst->effect)
     {
         {
@@ -320,6 +375,18 @@ __declspec (dllexport) int32 SF_VST2_SendNoteOn (int32 handle, int32 channel, in
     if (!inst->effect)
         return -2;
 
+    // T12: audio loop dang chay -> day vao SPSC (audio thread xu ly).
+    if (inst->audioRunning.load (std::memory_order_acquire))
+    {
+        sonicforge::MidiEvent ev = {};
+        ev.channel = channel;
+        ev.pitch = pitch;
+        ev.velocity = static_cast<float> (velocity) / 127.0f;
+        ev.noteOn = true;
+        inst->audio.pushMidi (ev);
+        return 0;
+    }
+
     char midiData[4] = {0};
     midiData[0] = static_cast<char> (0x90 | (channel & 0x0F));
     midiData[1] = static_cast<char> (pitch & 0x7F);
@@ -352,6 +419,18 @@ __declspec (dllexport) int32 SF_VST2_SendNoteOff (int32 handle, int32 channel, i
     if (!inst->effect)
         return -2;
 
+    // T12: audio loop dang chay -> day vao SPSC.
+    if (inst->audioRunning.load (std::memory_order_acquire))
+    {
+        sonicforge::MidiEvent ev = {};
+        ev.channel = channel;
+        ev.pitch = pitch;
+        ev.velocity = 0.0f;
+        ev.noteOn = false;
+        inst->audio.pushMidi (ev);
+        return 0;
+    }
+
     char midiData[4] = {0};
     midiData[0] = static_cast<char> (0x80 | (channel & 0x0F));
     midiData[1] = static_cast<char> (pitch & 0x7F);
@@ -464,4 +543,63 @@ __declspec (dllexport) int32 SF_VST2_GetParam (int32 handle, int32 paramIndex, d
     return 0;
 }
 
+// T12: bat native audio loop (SPSC + WASAPI) cho instance nay. Audio thread
+// goi vst2AudioProcess (effProcessEvents + processReplacing) moi block.
+__declspec (dllexport) int32 SF_VST2_AudioStart (int32 handle, int32 sampleRate,
+                                                 int32 blockSize, char* err, int32 err_cap)
+{
+    std::lock_guard<std::mutex> lock (g_mutex);
+    auto it = g_instances.find (handle);
+    if (it == g_instances.end ())
+        return -1;
+    Instance* inst = it->second.get ();
+    if (!inst->effect)
+        return -2;
+    inst->audioRunning.store (true, std::memory_order_release); // truoc khi thread chay
+    if (!inst->audio.start (sampleRate, blockSize, &vst2AudioProcess, inst, err, err_cap))
+    {
+        inst->audioRunning.store (false, std::memory_order_release);
+        return -3;
+    }
+    return 0;
+}
+
+__declspec (dllexport) int32 SF_VST2_AudioStop (int32 handle)
+{
+    std::lock_guard<std::mutex> lock (g_mutex);
+    auto it = g_instances.find (handle);
+    if (it == g_instances.end ())
+        return -1;
+    it->second->audioRunning.store (false, std::memory_order_release);
+    it->second->audio.stop ();
+    return 0;
+}
+
+__declspec (dllexport) int32 SF_VST2_AudioUnderruns (int32 handle)
+{
+    std::lock_guard<std::mutex> lock (g_mutex);
+    auto it = g_instances.find (handle);
+    if (it == g_instances.end ())
+        return -1;
+    return it->second->audio.underruns ();
+}
+
+__declspec (dllexport) int32 SF_VST2_AudioLatency (int32 handle)
+{
+    std::lock_guard<std::mutex> lock (g_mutex);
+    auto it = g_instances.find (handle);
+    if (it == g_instances.end ())
+        return -1;
+    return it->second->audio.latencySamples ();
+}
+
+__declspec (dllexport) int32 SF_VST2_AudioBlocks (int32 handle)
+{
+    std::lock_guard<std::mutex> lock (g_mutex);
+    auto it = g_instances.find (handle);
+    if (it == g_instances.end ())
+        return -1;
+    return it->second->audio.blocksRendered ();
+}
+
 } // extern "C"