From b50c816088ac7825e044430fe1ff804205fa402b Mon Sep 17 00:00:00 2001
From: Raju <raju.sharma>
Date: Mon, 23 Mar 2026 15:52:56 +0530
Subject: [PATCH] fix[notask]: replace global streaming state with per-instance
 map in whispercpp

The streaming processor used three process-global variables (g_streamingMtx,
g_streamingInstance, g_streamingProcessor) which limited the entire process
to a single streaming session and risked dangling-pointer access if the
owning AddonJs instance was destroyed without cleanup.

Replace with an unordered_map keyed by AddonJs* so each addon instance
independently owns its streaming session, eliminating the race condition
and enabling concurrent streaming across multiple instances.

Made-with: Cursor
---
 .../addon/src/addon/AddonJs.hpp               | 32 +++++++++++--------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/packages/qvac-lib-infer-whispercpp/addon/src/addon/AddonJs.hpp b/packages/qvac-lib-infer-whispercpp/addon/src/addon/AddonJs.hpp
index 09aeadd13b..a714b31cc3 100644
--- a/packages/qvac-lib-infer-whispercpp/addon/src/addon/AddonJs.hpp
+++ b/packages/qvac-lib-infer-whispercpp/addon/src/addon/AddonJs.hpp
@@ -5,6 +5,7 @@
 #include <mutex>
 #include <span>
 #include <string>
+#include <unordered_map>
 #include <vector>
 
 #include <js.h>
@@ -25,8 +26,9 @@
 namespace qvac_lib_inference_addon_whisper {
 
 inline std::mutex g_streamingMtx;
-inline qvac_lib_inference_addon_cpp::AddonJs* g_streamingInstance = nullptr;
-inline std::unique_ptr<StreamingProcessor> g_streamingProcessor;
+inline std::unordered_map<
+    qvac_lib_inference_addon_cpp::AddonJs*,
+    std::unique_ptr<StreamingProcessor>> g_streamingSessions;
 
 namespace js = qvac_lib_inference_addon_cpp::js;
 using qvac_lib_inference_addon_cpp::OutputQueue;
@@ -245,15 +247,14 @@ startStreaming(js_env_t* env, js_callback_info_t* info) try {
   {
     std::lock_guard lock(g_streamingMtx);
 
-    if (g_streamingProcessor) {
+    if (g_streamingSessions.count(&instance) != 0) {
       throw std::runtime_error(
-          "Streaming session already active");
+          "Streaming session already active for this instance");
     }
 
     auto& whisperModel =
         dynamic_cast<WhisperModel&>(instance.addonCpp->model.get());
-    g_streamingInstance = &instance;
-    g_streamingProcessor = std::make_unique<StreamingProcessor>(
+    g_streamingSessions[&instance] = std::make_unique<StreamingProcessor>(
         whisperModel,
         instance.addonCpp->outputQueue,
         config);
@@ -296,10 +297,11 @@ appendStreamingAudio(js_env_t* env, js_callback_info_t* info) try {
   StreamingProcessor* processor = nullptr;
   {
     std::lock_guard lock(g_streamingMtx);
-    if (!g_streamingProcessor || g_streamingInstance != &instance) {
+    auto it = g_streamingSessions.find(&instance);
+    if (it == g_streamingSessions.end()) {
       throw std::runtime_error("No active streaming session for this instance");
     }
-    processor = g_streamingProcessor.get();
+    processor = it->second.get();
   }
 
   processor->appendAudio(std::move(samples));
@@ -316,11 +318,12 @@ cleanupStreamingSession(
   std::unique_ptr<StreamingProcessor> processor;
   {
     std::lock_guard lock(g_streamingMtx);
-    if (!g_streamingProcessor || g_streamingInstance != &instance) {
+    auto it = g_streamingSessions.find(&instance);
+    if (it == g_streamingSessions.end()) {
       return false;
     }
-    processor = std::move(g_streamingProcessor);
-    g_streamingInstance = nullptr;
+    processor = std::move(it->second);
+    g_streamingSessions.erase(it);
   }
   if (forceful) {
     processor->cancel();
@@ -340,10 +343,11 @@ cancelWithStreaming(js_env_t* env, js_callback_info_t* info) try {
   std::shared_ptr<StreamingProcessor> processor;
   {
     std::lock_guard lock(g_streamingMtx);
-    if (g_streamingProcessor && g_streamingInstance == &instance) {
+    auto it = g_streamingSessions.find(&instance);
+    if (it != g_streamingSessions.end()) {
       processor = std::shared_ptr<StreamingProcessor>(
-          std::move(g_streamingProcessor));
-      g_streamingInstance = nullptr;
+          std::move(it->second));
+      g_streamingSessions.erase(it);
     }
   }