astro-ghostcms/.pnpm-store/v3/files/d2/3b2c9fb411ae2336a30b0bf751c...

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"use strict";
/* --------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
* ------------------------------------------------------------------------------------------ */
Object.defineProperty(exports, "__esModule", { value: true });
exports.Semaphore = void 0;
const ral_1 = require("./ral");
class Semaphore {
constructor(capacity = 1) {
if (capacity <= 0) {
throw new Error('Capacity must be greater than 0');
}
this._capacity = capacity;
this._active = 0;
this._waiting = [];
}
lock(thunk) {
return new Promise((resolve, reject) => {
this._waiting.push({ thunk, resolve, reject });
this.runNext();
});
}
get active() {
return this._active;
}
runNext() {
if (this._waiting.length === 0 || this._active === this._capacity) {
return;
}
(0, ral_1.default)().timer.setImmediate(() => this.doRunNext());
}
doRunNext() {
if (this._waiting.length === 0 || this._active === this._capacity) {
return;
}
const next = this._waiting.shift();
this._active++;
if (this._active > this._capacity) {
throw new Error(`To many thunks active`);
}
try {
const result = next.thunk();
if (result instanceof Promise) {
result.then((value) => {
this._active--;
next.resolve(value);
this.runNext();
}, (err) => {
this._active--;
next.reject(err);
this.runNext();
});
}
else {
this._active--;
next.resolve(result);
this.runNext();
}
}
catch (err) {
this._active--;
next.reject(err);
this.runNext();
}
}
}
exports.Semaphore = Semaphore;