diff options
author | Bartek IwaĆczuk <biwanczuk@gmail.com> | 2020-03-11 10:53:06 +0100 |
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committer | GitHub <noreply@github.com> | 2020-03-11 10:53:06 +0100 |
commit | 99a0c6df79b903e4fe72ce066787039bdede3868 (patch) | |
tree | 1c0abdb964a2e052b593dc8fa3e515f76dbc0642 /cli/js/timers.ts | |
parent | 94f4c6807a34a564f567b984e71e36e9cb9c5005 (diff) |
reorg: cli/js/compiler/, move more API to cli/js/web/ (#4310)
- moves compiler implementation to "cli/js/compiler/" directory
- moves more APIs to "cli/js/web":
* "console.ts"
* "console_table.ts"
* "performance.ts"
* "timers.ts"
* "workers.ts"
- removes some dead code from "cli/js/"
Diffstat (limited to 'cli/js/timers.ts')
-rw-r--r-- | cli/js/timers.ts | 315 |
1 files changed, 0 insertions, 315 deletions
diff --git a/cli/js/timers.ts b/cli/js/timers.ts deleted file mode 100644 index 844a0b204..000000000 --- a/cli/js/timers.ts +++ /dev/null @@ -1,315 +0,0 @@ -// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license. -import { assert } from "./util.ts"; -import { startGlobalTimer, stopGlobalTimer } from "./ops/timers.ts"; -import { RBTree } from "./rbtree.ts"; - -const { console } = globalThis; - -interface Timer { - id: number; - callback: () => void; - delay: number; - due: number; - repeat: boolean; - scheduled: boolean; -} - -// Timeout values > TIMEOUT_MAX are set to 1. -const TIMEOUT_MAX = 2 ** 31 - 1; - -let globalTimeoutDue: number | null = null; - -let nextTimerId = 1; -const idMap = new Map<number, Timer>(); -type DueNode = { due: number; timers: Timer[] }; -const dueTree = new RBTree<DueNode>((a, b) => a.due - b.due); - -function clearGlobalTimeout(): void { - globalTimeoutDue = null; - stopGlobalTimer(); -} - -let pendingEvents = 0; -const pendingFireTimers: Timer[] = []; -let hasPendingFireTimers = false; -let pendingScheduleTimers: Timer[] = []; - -async function setGlobalTimeout(due: number, now: number): Promise<void> { - // 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. - await startGlobalTimer(timeout); - pendingEvents--; - // eslint-disable-next-line @typescript-eslint/no-use-before-define - fireTimers(); -} - -function setOrClearGlobalTimeout(due: number | null, now: number): void { - if (due == null) { - clearGlobalTimeout(); - } else { - setGlobalTimeout(due, now); - } -} - -function schedule(timer: Timer, now: number): void { - assert(!timer.scheduled); - assert(now <= timer.due); - // There are more timers pending firing. - // We must ensure new timer scheduled after them. - // Push them to a queue that would be depleted after last pending fire - // timer is fired. - // (This also implies behavior of setInterval) - if (hasPendingFireTimers) { - pendingScheduleTimers.push(timer); - return; - } - // 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: Timer): void { - // 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 = pendingScheduleTimers.indexOf(timer)) >= 0) { - pendingScheduleTimers.splice(index); - return; - } - 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: DueNode | null = dueTree.min(); - setOrClearGlobalTimeout(nextDueNode && nextDueNode.due, Date.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: Timer): void { - // 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 = Date.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 fireTimers(): void { - const now = Date.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: DueNode | null; - 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); - } - } - if (pendingFireTimers.length > 0) { - hasPendingFireTimers = true; - // Fire the list of pending timers as a chain of microtasks. - globalThis.queueMicrotask(firePendingTimers); - } else { - setOrClearGlobalTimeout(nextDueNode && nextDueNode.due, now); - } -} - -function firePendingTimers(): void { - if (pendingFireTimers.length === 0) { - // All timer tasks are done. - hasPendingFireTimers = false; - // Schedule all new timers pushed during previous timer executions - const now = Date.now(); - for (const newTimer of pendingScheduleTimers) { - newTimer.due = Math.max(newTimer.due, now); - schedule(newTimer, now); - } - pendingScheduleTimers = []; - // Reschedule for next round of timeout. - const nextDueNode = dueTree.min(); - const due = nextDueNode && Math.max(nextDueNode.due, now); - setOrClearGlobalTimeout(due, now); - } else { - // Fire a single timer and allow its children microtasks scheduled first. - fire(pendingFireTimers.shift()!); - // ...and we schedule next timer after this. - globalThis.queueMicrotask(firePendingTimers); - } -} - -export type Args = unknown[]; - -function checkThis(thisArg: unknown): void { - if (thisArg !== null && thisArg !== undefined && thisArg !== globalThis) { - throw new TypeError("Illegal invocation"); - } -} - -function checkBigInt(n: unknown): void { - if (typeof n === "bigint") { - throw new TypeError("Cannot convert a BigInt value to a number"); - } -} - -function setTimer( - cb: (...args: Args) => void, - delay: number, - args: Args, - repeat: boolean -): number { - // Bind `args` to the callback and bind `this` to globalThis(global). - const callback: () => void = 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 = Date.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; -} - -/** Sets a timer which executes a function once after the timer expires. */ -export function setTimeout( - cb: (...args: Args) => void, - delay = 0, - ...args: Args -): number { - checkBigInt(delay); - // @ts-ignore - checkThis(this); - return setTimer(cb, delay, args, false); -} - -/** Repeatedly calls a function, with a fixed time delay between each call. */ -export function setInterval( - cb: (...args: Args) => void, - delay = 0, - ...args: Args -): number { - checkBigInt(delay); - // @ts-ignore - checkThis(this); - return setTimer(cb, delay, args, true); -} - -/** Clears a previously set timer by id. AKA clearTimeout and clearInterval. */ -function clearTimer(id: number): void { - 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); -} - -export function clearTimeout(id = 0): void { - checkBigInt(id); - if (id === 0) { - return; - } - clearTimer(id); -} - -export function clearInterval(id = 0): void { - checkBigInt(id); - if (id === 0) { - return; - } - clearTimer(id); -} |