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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// deno-lint-ignore-file
const targetDir = Deno.execPath().replace(/[^\/\\]+$/, "");const [libPrefix, libSuffix] = {  darwin: ["lib", "dylib"],  linux: ["lib", "so"],  windows: ["", "dll"],}[Deno.build.os];const libPath = `${targetDir}/${libPrefix}test_ffi.${libSuffix}`;
const resourcesPre = Deno.resources();
const dylib = Deno.dlopen(libPath, {  store_function: {    parameters: ["function"],    result: "void",  },  call_stored_function: {    parameters: [],    result: "void",  },  call_stored_function_thread_safe: {    parameters: [],    result: "void",  },});
let resolveWorker;let workerResponsePromise;
const worker = new Worker(  new URL("./thread_safe_test_worker.js", import.meta.url).href,  { type: "module" },);
worker.addEventListener("message", () => {  if (resolveWorker) {    resolveWorker();  }});
const sendWorkerMessage = async (data) => {  workerResponsePromise = new Promise((res) => {    resolveWorker = res;  });  worker.postMessage(data);  await workerResponsePromise;};
// Test step 1: Register main thread callback, trigger on worker thread
const mainThreadCallback = new Deno.UnsafeCallback(  { parameters: [], result: "void" },  () => {    console.log("Callback on main thread");  },);
mainThreadCallback.ref();
dylib.symbols.store_function(mainThreadCallback.pointer);
await sendWorkerMessage("call");
// Test step 2: Register on worker thread, trigger on main thread
await sendWorkerMessage("register");
dylib.symbols.call_stored_function();
// Unref both main and worker thread callbacks and terminate the wrorker: Note, the stored function pointer in lib is now dangling.
mainThreadCallback.unref();await sendWorkerMessage("unref");worker.terminate();
// Test step 3: Register a callback that will be the only thing left keeping the isolate from exiting.// Rely on it to keep Deno running until the callback comes in and unrefs the callback, after which Deno should exit.
const cleanupCallback = new Deno.UnsafeCallback(  { parameters: [], result: "void" },  () => {    console.log("Callback being called");    Promise.resolve().then(() => cleanup());  },);
cleanupCallback.ref();
function cleanup() {  cleanupCallback.unref();  console.log("Isolate should now exit");}
dylib.symbols.store_function(cleanupCallback.pointer);
console.log(  "Calling callback, isolate should stay asleep until callback is called",);dylib.symbols.call_stored_function_thread_safe();