godot-ultimate-tutorial/web/Tutorial.worker.js

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2023-08-15 20:51:29 +00:00
/**
* @license
* Copyright 2015 The Emscripten Authors
* SPDX-License-Identifier: MIT
*/
// Pthread Web Worker startup routine:
// This is the entry point file that is loaded first by each Web Worker
// that executes pthreads on the Emscripten application.
'use strict';
var Module = {};
// Thread-local guard variable for one-time init of the JS state
var initializedJS = false;
// Proxying queues that were notified before the thread started and need to be
// executed as part of startup.
var pendingNotifiedProxyingQueues = [];
function assert(condition, text) {
if (!condition) abort('Assertion failed: ' + text);
}
function threadPrintErr() {
var text = Array.prototype.slice.call(arguments).join(' ');
console.error(text);
}
function threadAlert() {
var text = Array.prototype.slice.call(arguments).join(' ');
postMessage({cmd: 'alert', text: text, threadId: Module['_pthread_self']()});
}
// We don't need out() for now, but may need to add it if we want to use it
// here. Or, if this code all moves into the main JS, that problem will go
// away. (For now, adding it here increases code size for no benefit.)
var out = () => { throw 'out() is not defined in worker.js.'; }
var err = threadPrintErr;
self.alert = threadAlert;
Module['instantiateWasm'] = (info, receiveInstance) => {
// Instantiate from the module posted from the main thread.
// We can just use sync instantiation in the worker.
var instance = new WebAssembly.Instance(Module['wasmModule'], info);
// TODO: Due to Closure regression https://github.com/google/closure-compiler/issues/3193,
// the above line no longer optimizes out down to the following line.
// When the regression is fixed, we can remove this if/else.
receiveInstance(instance);
// We don't need the module anymore; new threads will be spawned from the main thread.
Module['wasmModule'] = null;
return instance.exports;
}
self.onmessage = (e) => {
try {
if (e.data.cmd === 'load') { // Preload command that is called once per worker to parse and load the Emscripten code.
// Module and memory were sent from main thread
Module['wasmModule'] = e.data.wasmModule;
Module['wasmMemory'] = e.data.wasmMemory;
Module['buffer'] = Module['wasmMemory'].buffer;
Module['ENVIRONMENT_IS_PTHREAD'] = true;
if (typeof e.data.urlOrBlob == 'string') {
importScripts(e.data.urlOrBlob);
} else {
var objectUrl = URL.createObjectURL(e.data.urlOrBlob);
importScripts(objectUrl);
URL.revokeObjectURL(objectUrl);
}
Godot(Module).then(function (instance) {
Module = instance;
});
} else if (e.data.cmd === 'run') {
// This worker was idle, and now should start executing its pthread entry
// point.
// performance.now() is specced to return a wallclock time in msecs since
// that Web Worker/main thread launched. However for pthreads this can
// cause subtle problems in emscripten_get_now() as this essentially
// would measure time from pthread_create(), meaning that the clocks
// between each threads would be wildly out of sync. Therefore sync all
// pthreads to the clock on the main browser thread, so that different
// threads see a somewhat coherent clock across each of them
// (+/- 0.1msecs in testing).
Module['__performance_now_clock_drift'] = performance.now() - e.data.time;
// Pass the thread address to wasm to store it for fast access.
Module['__emscripten_thread_init'](e.data.pthread_ptr, /*isMainBrowserThread=*/0, /*isMainRuntimeThread=*/0, /*canBlock=*/1);
assert(e.data.pthread_ptr);
// Also call inside JS module to set up the stack frame for this pthread in JS module scope
Module['establishStackSpace']();
Module['PThread'].receiveObjectTransfer(e.data);
Module['PThread'].threadInitTLS();
if (!initializedJS) {
// Execute any proxied work that came in before the thread was
// initialized. Only do this once because it is only possible for
// proxying notifications to arrive before thread initialization on
// fresh workers.
pendingNotifiedProxyingQueues.forEach(queue => {
Module['executeNotifiedProxyingQueue'](queue);
});
pendingNotifiedProxyingQueues = [];
initializedJS = true;
}
try {
Module['invokeEntryPoint'](e.data.start_routine, e.data.arg);
} catch(ex) {
if (ex != 'unwind') {
// ExitStatus not present in MINIMAL_RUNTIME
if (ex instanceof Module['ExitStatus']) {
if (Module['keepRuntimeAlive']()) {
err('Pthread 0x' + Module['_pthread_self']().toString(16) + ' called exit(), staying alive due to noExitRuntime.');
} else {
err('Pthread 0x' + Module['_pthread_self']().toString(16) + ' called exit(), calling _emscripten_thread_exit.');
Module['__emscripten_thread_exit'](ex.status);
}
}
else
{
// The pthread "crashed". Do not call `_emscripten_thread_exit` (which
// would make this thread joinable. Instead, re-throw the exception
// and let the top level handler propagate it back to the main thread.
throw ex;
}
} else {
// else e == 'unwind', and we should fall through here and keep the pthread alive for asynchronous events.
err('Pthread 0x' + Module['_pthread_self']().toString(16) + ' completed its main entry point with an `unwind`, keeping the worker alive for asynchronous operation.');
}
}
} else if (e.data.cmd === 'cancel') { // Main thread is asking for a pthread_cancel() on this thread.
if (Module['_pthread_self']()) {
Module['__emscripten_thread_exit'](-1/*PTHREAD_CANCELED*/);
}
} else if (e.data.target === 'setimmediate') {
// no-op
} else if (e.data.cmd === 'processProxyingQueue') {
if (initializedJS) {
Module['executeNotifiedProxyingQueue'](e.data.queue);
} else {
// Defer executing this queue until the runtime is initialized.
pendingNotifiedProxyingQueues.push(e.data.queue);
}
} else {
err('worker.js received unknown command ' + e.data.cmd);
err(e.data);
}
} catch(ex) {
err('worker.js onmessage() captured an uncaught exception: ' + ex);
if (ex && ex.stack) err(ex.stack);
if (Module['__emscripten_thread_crashed']) {
Module['__emscripten_thread_crashed']();
}
throw ex;
}
};