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diff --git a/runtime/js/11_timers.js b/runtime/js/11_timers.js
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+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+((window) => {
+ const assert = window.__bootstrap.util.assert;
+ const core = window.Deno.core;
+ const { sendSync } = window.__bootstrap.dispatchMinimal;
+
+ function opStopGlobalTimer() {
+ core.jsonOpSync("op_global_timer_stop");
+ }
+
+ function opStartGlobalTimer(timeout) {
+ return core.jsonOpSync("op_global_timer_start", { timeout });
+ }
+
+ async function opWaitGlobalTimer() {
+ await core.jsonOpAsync("op_global_timer");
+ }
+
+ const nowBytes = new Uint8Array(8);
+ function opNow() {
+ sendSync("op_now", 0, nowBytes);
+ return new DataView(nowBytes.buffer).getFloat64();
+ }
+
+ function sleepSync(millis = 0) {
+ return core.jsonOpSync("op_sleep_sync", { millis });
+ }
+
+ // Derived from https://github.com/vadimg/js_bintrees. MIT Licensed.
+
+ class RBNode {
+ constructor(data) {
+ this.data = data;
+ this.left = null;
+ this.right = null;
+ this.red = true;
+ }
+
+ getChild(dir) {
+ return dir ? this.right : this.left;
+ }
+
+ setChild(dir, val) {
+ if (dir) {
+ this.right = val;
+ } else {
+ this.left = val;
+ }
+ }
+ }
+
+ class RBTree {
+ #comparator = null;
+ #root = null;
+
+ constructor(comparator) {
+ this.#comparator = comparator;
+ this.#root = null;
+ }
+
+ /** Returns `null` if tree is empty. */
+ min() {
+ let res = this.#root;
+ if (res === null) {
+ return null;
+ }
+ while (res.left !== null) {
+ res = res.left;
+ }
+ return res.data;
+ }
+
+ /** Returns node `data` if found, `null` otherwise. */
+ find(data) {
+ let res = this.#root;
+ while (res !== null) {
+ const c = this.#comparator(data, res.data);
+ if (c === 0) {
+ return res.data;
+ } else {
+ res = res.getChild(c > 0);
+ }
+ }
+ return null;
+ }
+
+ /** returns `true` if inserted, `false` if duplicate. */
+ insert(data) {
+ let ret = false;
+
+ if (this.#root === null) {
+ // empty tree
+ this.#root = new RBNode(data);
+ ret = true;
+ } else {
+ const head = new RBNode(null); // fake tree root
+
+ let dir = 0;
+ let last = 0;
+
+ // setup
+ let gp = null; // grandparent
+ let ggp = head; // grand-grand-parent
+ let p = null; // parent
+ let node = this.#root;
+ ggp.right = this.#root;
+
+ // search down
+ while (true) {
+ if (node === null) {
+ // insert new node at the bottom
+ node = new RBNode(data);
+ p.setChild(dir, node);
+ ret = true;
+ } else if (isRed(node.left) && isRed(node.right)) {
+ // color flip
+ node.red = true;
+ node.left.red = false;
+ node.right.red = false;
+ }
+
+ // fix red violation
+ if (isRed(node) && isRed(p)) {
+ const dir2 = ggp.right === gp;
+
+ assert(gp);
+ if (node === p.getChild(last)) {
+ ggp.setChild(dir2, singleRotate(gp, !last));
+ } else {
+ ggp.setChild(dir2, doubleRotate(gp, !last));
+ }
+ }
+
+ const cmp = this.#comparator(node.data, data);
+
+ // stop if found
+ if (cmp === 0) {
+ break;
+ }
+
+ last = dir;
+ dir = Number(cmp < 0); // Fix type
+
+ // update helpers
+ if (gp !== null) {
+ ggp = gp;
+ }
+ gp = p;
+ p = node;
+ node = node.getChild(dir);
+ }
+
+ // update root
+ this.#root = head.right;
+ }
+
+ // make root black
+ this.#root.red = false;
+
+ return ret;
+ }
+
+ /** Returns `true` if removed, `false` if not found. */
+ remove(data) {
+ if (this.#root === null) {
+ return false;
+ }
+
+ const head = new RBNode(null); // fake tree root
+ let node = head;
+ node.right = this.#root;
+ let p = null; // parent
+ let gp = null; // grand parent
+ let found = null; // found item
+ let dir = 1;
+
+ while (node.getChild(dir) !== null) {
+ const last = dir;
+
+ // update helpers
+ gp = p;
+ p = node;
+ node = node.getChild(dir);
+
+ const cmp = this.#comparator(data, node.data);
+
+ dir = cmp > 0;
+
+ // save found node
+ if (cmp === 0) {
+ found = node;
+ }
+
+ // push the red node down
+ if (!isRed(node) && !isRed(node.getChild(dir))) {
+ if (isRed(node.getChild(!dir))) {
+ const sr = singleRotate(node, dir);
+ p.setChild(last, sr);
+ p = sr;
+ } else if (!isRed(node.getChild(!dir))) {
+ const sibling = p.getChild(!last);
+ if (sibling !== null) {
+ if (
+ !isRed(sibling.getChild(!last)) &&
+ !isRed(sibling.getChild(last))
+ ) {
+ // color flip
+ p.red = false;
+ sibling.red = true;
+ node.red = true;
+ } else {
+ assert(gp);
+ const dir2 = gp.right === p;
+
+ if (isRed(sibling.getChild(last))) {
+ gp.setChild(dir2, doubleRotate(p, last));
+ } else if (isRed(sibling.getChild(!last))) {
+ gp.setChild(dir2, singleRotate(p, last));
+ }
+
+ // ensure correct coloring
+ const gpc = gp.getChild(dir2);
+ assert(gpc);
+ gpc.red = true;
+ node.red = true;
+ assert(gpc.left);
+ gpc.left.red = false;
+ assert(gpc.right);
+ gpc.right.red = false;
+ }
+ }
+ }
+ }
+ }
+
+ // replace and remove if found
+ if (found !== null) {
+ found.data = node.data;
+ assert(p);
+ p.setChild(p.right === node, node.getChild(node.left === null));
+ }
+
+ // update root and make it black
+ this.#root = head.right;
+ if (this.#root !== null) {
+ this.#root.red = false;
+ }
+
+ return found !== null;
+ }
+ }
+
+ function isRed(node) {
+ return node !== null && node.red;
+ }
+
+ function singleRotate(root, dir) {
+ const save = root.getChild(!dir);
+ assert(save);
+
+ root.setChild(!dir, save.getChild(dir));
+ save.setChild(dir, root);
+
+ root.red = true;
+ save.red = false;
+
+ return save;
+ }
+
+ function doubleRotate(root, dir) {
+ root.setChild(!dir, singleRotate(root.getChild(!dir), !dir));
+ return singleRotate(root, dir);
+ }
+
+ const { console } = globalThis;
+ const OriginalDate = Date;
+
+ // Timeout values > TIMEOUT_MAX are set to 1.
+ const TIMEOUT_MAX = 2 ** 31 - 1;
+
+ let globalTimeoutDue = null;
+
+ let nextTimerId = 1;
+ const idMap = new Map();
+ const dueTree = new RBTree((a, b) => a.due - b.due);
+
+ function clearGlobalTimeout() {
+ globalTimeoutDue = null;
+ opStopGlobalTimer();
+ }
+
+ let pendingEvents = 0;
+ const pendingFireTimers = [];
+
+ /** Process and run a single ready timer macrotask.
+ * This function should be registered through Deno.core.setMacrotaskCallback.
+ * Returns true when all ready macrotasks have been processed, false if more
+ * ready ones are available. The Isolate future would rely on the return value
+ * to repeatedly invoke this function until depletion. Multiple invocations
+ * of this function one at a time ensures newly ready microtasks are processed
+ * before next macrotask timer callback is invoked. */
+ function handleTimerMacrotask() {
+ if (pendingFireTimers.length > 0) {
+ fire(pendingFireTimers.shift());
+ return pendingFireTimers.length === 0;
+ }
+ return true;
+ }
+
+ async function setGlobalTimeout(due, now) {
+ // Since JS and Rust don't use the same clock, pass the time to rust as a
+ // relative time value. On the Rust side we'll turn that into an absolute
+ // value again.
+ const timeout = due - now;
+ assert(timeout >= 0);
+ // Send message to the backend.
+ globalTimeoutDue = due;
+ pendingEvents++;
+ // FIXME(bartlomieju): this is problematic, because `clearGlobalTimeout`
+ // is synchronous. That means that timer is cancelled, but this promise is still pending
+ // until next turn of event loop. This leads to "leaking of async ops" in tests;
+ // because `clearTimeout/clearInterval` might be the last statement in test function
+ // `opSanitizer` will immediately complain that there is pending op going on, unless
+ // some timeout/defer is put in place to allow promise resolution.
+ // Ideally `clearGlobalTimeout` doesn't return until this op is resolved, but
+ // I'm not if that's possible.
+ opStartGlobalTimer(timeout);
+ await opWaitGlobalTimer();
+ pendingEvents--;
+ // eslint-disable-next-line @typescript-eslint/no-use-before-define
+ prepareReadyTimers();
+ }
+
+ function prepareReadyTimers() {
+ const now = OriginalDate.now();
+ // Bail out if we're not expecting the global timer to fire.
+ if (globalTimeoutDue === null || pendingEvents > 0) {
+ return;
+ }
+ // After firing the timers that are due now, this will hold the first timer
+ // list that hasn't fired yet.
+ let nextDueNode;
+ while ((nextDueNode = dueTree.min()) !== null && nextDueNode.due <= now) {
+ dueTree.remove(nextDueNode);
+ // Fire all the timers in the list.
+ for (const timer of nextDueNode.timers) {
+ // With the list dropped, the timer is no longer scheduled.
+ timer.scheduled = false;
+ // Place the callback to pending timers to fire.
+ pendingFireTimers.push(timer);
+ }
+ }
+ setOrClearGlobalTimeout(nextDueNode && nextDueNode.due, now);
+ }
+
+ function setOrClearGlobalTimeout(due, now) {
+ if (due == null) {
+ clearGlobalTimeout();
+ } else {
+ setGlobalTimeout(due, now);
+ }
+ }
+
+ function schedule(timer, now) {
+ assert(!timer.scheduled);
+ assert(now <= timer.due);
+ // Find or create the list of timers that will fire at point-in-time `due`.
+ const maybeNewDueNode = { due: timer.due, timers: [] };
+ let dueNode = dueTree.find(maybeNewDueNode);
+ if (dueNode === null) {
+ dueTree.insert(maybeNewDueNode);
+ dueNode = maybeNewDueNode;
+ }
+ // Append the newly scheduled timer to the list and mark it as scheduled.
+ dueNode.timers.push(timer);
+ timer.scheduled = true;
+ // If the new timer is scheduled to fire before any timer that existed before,
+ // update the global timeout to reflect this.
+ if (globalTimeoutDue === null || globalTimeoutDue > timer.due) {
+ setOrClearGlobalTimeout(timer.due, now);
+ }
+ }
+
+ function unschedule(timer) {
+ // Check if our timer is pending scheduling or pending firing.
+ // If either is true, they are not in tree, and their idMap entry
+ // will be deleted soon. Remove it from queue.
+ let index = -1;
+ if ((index = pendingFireTimers.indexOf(timer)) >= 0) {
+ pendingFireTimers.splice(index);
+ return;
+ }
+ // If timer is not in the 2 pending queues and is unscheduled,
+ // it is not in the tree.
+ if (!timer.scheduled) {
+ return;
+ }
+ const searchKey = { due: timer.due, timers: [] };
+ // Find the list of timers that will fire at point-in-time `due`.
+ const list = dueTree.find(searchKey).timers;
+ if (list.length === 1) {
+ // Time timer is the only one in the list. Remove the entire list.
+ assert(list[0] === timer);
+ dueTree.remove(searchKey);
+ // If the unscheduled timer was 'next up', find when the next timer that
+ // still exists is due, and update the global alarm accordingly.
+ if (timer.due === globalTimeoutDue) {
+ const nextDueNode = dueTree.min();
+ setOrClearGlobalTimeout(
+ nextDueNode && nextDueNode.due,
+ OriginalDate.now(),
+ );
+ }
+ } else {
+ // Multiple timers that are due at the same point in time.
+ // Remove this timer from the list.
+ const index = list.indexOf(timer);
+ assert(index > -1);
+ list.splice(index, 1);
+ }
+ }
+
+ function fire(timer) {
+ // If the timer isn't found in the ID map, that means it has been cancelled
+ // between the timer firing and the promise callback (this function).
+ if (!idMap.has(timer.id)) {
+ return;
+ }
+ // Reschedule the timer if it is a repeating one, otherwise drop it.
+ if (!timer.repeat) {
+ // One-shot timer: remove the timer from this id-to-timer map.
+ idMap.delete(timer.id);
+ } else {
+ // Interval timer: compute when timer was supposed to fire next.
+ // However make sure to never schedule the next interval in the past.
+ const now = OriginalDate.now();
+ timer.due = Math.max(now, timer.due + timer.delay);
+ schedule(timer, now);
+ }
+ // Call the user callback. Intermediate assignment is to avoid leaking `this`
+ // to it, while also keeping the stack trace neat when it shows up in there.
+ const callback = timer.callback;
+ callback();
+ }
+
+ function checkThis(thisArg) {
+ if (thisArg !== null && thisArg !== undefined && thisArg !== globalThis) {
+ throw new TypeError("Illegal invocation");
+ }
+ }
+
+ function checkBigInt(n) {
+ if (typeof n === "bigint") {
+ throw new TypeError("Cannot convert a BigInt value to a number");
+ }
+ }
+
+ function setTimer(
+ cb,
+ delay,
+ args,
+ repeat,
+ ) {
+ // Bind `args` to the callback and bind `this` to globalThis(global).
+ const callback = cb.bind(globalThis, ...args);
+ // In the browser, the delay value must be coercible to an integer between 0
+ // and INT32_MAX. Any other value will cause the timer to fire immediately.
+ // We emulate this behavior.
+ const now = OriginalDate.now();
+ if (delay > TIMEOUT_MAX) {
+ console.warn(
+ `${delay} does not fit into` +
+ " a 32-bit signed integer." +
+ "\nTimeout duration was set to 1.",
+ );
+ delay = 1;
+ }
+ delay = Math.max(0, delay | 0);
+
+ // Create a new, unscheduled timer object.
+ const timer = {
+ id: nextTimerId++,
+ callback,
+ args,
+ delay,
+ due: now + delay,
+ repeat,
+ scheduled: false,
+ };
+ // Register the timer's existence in the id-to-timer map.
+ idMap.set(timer.id, timer);
+ // Schedule the timer in the due table.
+ schedule(timer, now);
+ return timer.id;
+ }
+
+ function setTimeout(
+ cb,
+ delay = 0,
+ ...args
+ ) {
+ checkBigInt(delay);
+ checkThis(this);
+ return setTimer(cb, delay, args, false);
+ }
+
+ function setInterval(
+ cb,
+ delay = 0,
+ ...args
+ ) {
+ checkBigInt(delay);
+ checkThis(this);
+ return setTimer(cb, delay, args, true);
+ }
+
+ function clearTimer(id) {
+ id = Number(id);
+ const timer = idMap.get(id);
+ if (timer === undefined) {
+ // Timer doesn't exist any more or never existed. This is not an error.
+ return;
+ }
+ // Unschedule the timer if it is currently scheduled, and forget about it.
+ unschedule(timer);
+ idMap.delete(timer.id);
+ }
+
+ function clearTimeout(id = 0) {
+ checkBigInt(id);
+ if (id === 0) {
+ return;
+ }
+ clearTimer(id);
+ }
+
+ function clearInterval(id = 0) {
+ checkBigInt(id);
+ if (id === 0) {
+ return;
+ }
+ clearTimer(id);
+ }
+
+ window.__bootstrap.timers = {
+ clearInterval,
+ setInterval,
+ clearTimeout,
+ setTimeout,
+ handleTimerMacrotask,
+ opStopGlobalTimer,
+ opStartGlobalTimer,
+ opNow,
+ sleepSync,
+ };
+})(this);
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-27 13:33:08 +0000