Whisper.cpp Node.js Addon "Pause & Stop" function are not implemented?

[MaurUppi]

I noticed that the ASR function has a pause or cancel button, but both are malfunctioning.
Questions:

1. Can you confirm?
2. The root reason is whisper.cpp Node.js Addon does not provide an API for it?
3. IF both are TRUE, shall both buttons be turned gray (disabled) when the task is working on?

Meanwhile

• Did the current whisper addon support JavaScript cancellation?

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Critical Analysis: Whisper Addon Cancellation Limitation

Date: 2025-08-08
Status: ❌ FUNDAMENTAL ARCHITECTURAL LIMITATION DISCOVERED
Root Cause: The current whisper.cpp addon does NOT support JavaScript-level cancellation

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🚨 Discovery Summary

After investigating the crash logs and addon source code, I discovered that the fundamental assumption about abort_callback support was WRONG.

What I Thought vs Reality

What I Implemented	What Actually Exists
✅ abort_callback: () => boolean	❌ NOT SUPPORTED - Only native C++ static bool
✅ JavaScript function controls cancellation	❌ NOT EXPOSED - Hardcoded in addon
✅ progress_callback returns control values	❌ VOID FUNCTION - UI updates only

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🔍 Addon Analysis (whisper.cpp-openvino/examples/addon.node)

What the Addon Actually Supports

// addon.cpp lines 414-418: ONLY progress_callback is exposed to JavaScript
Napi::Function progress_callback;
if (whisper_params.Has("progress_callback") && whisper_params.Get("progress_callback").IsFunction()) {
    progress_callback = whisper_params.Get("progress_callback").As<Napi::Function>();
}

// addon.cpp lines 330-334: progress_callback is wrapped in native function
wparams.progress_callback = [](struct whisper_context *, struct whisper_state *, int progress, void * user_data) {
    ProgressWorker* worker = static_cast<ProgressWorker*>(user_data);
    worker->OnProgress(progress);  // This calls JavaScript asynchronously
};

Abort Mechanism Reality

// addon.cpp lines 336-339: abort_callback uses STATIC VARIABLE, not JS function
static bool is_aborted = false; // Note: this should be atomic to avoid data races

// The abort mechanism is NOT exposed to JavaScript at all

[buxuku]

Yes, The root reason is whisper.cpp Node.js Addon does not provide an API.
Therefore, at this stage, the pause only supports suspending tasks that have not yet started under batch tasks.