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1'use strict';
2
3Object.defineProperty(exports, '__esModule', {
4 value: true
5});
6exports.default = void 0;
7
8function _defineProperty(obj, key, value) {
9 if (key in obj) {
10 Object.defineProperty(obj, key, {
11 value: value,
12 enumerable: true,
13 configurable: true,
14 writable: true
15 });
16 } else {
17 obj[key] = value;
18 }
19 return obj;
20}
21
22/**
23 * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
24 *
25 * This source code is licensed under the MIT license found in the
26 * LICENSE file in the root directory of this source tree.
27 */
28
29/**
30 * First-in, First-out task queue that manages a dedicated pool
31 * for each worker as well as a shared queue. The FIFO ordering is guaranteed
32 * across the worker specific and shared queue.
33 */
34class FifoQueue {
35 constructor() {
36 _defineProperty(this, '_workerQueues', []);
37
38 _defineProperty(this, '_sharedQueue', new InternalQueue());
39 }
40
41 enqueue(task, workerId) {
42 if (workerId == null) {
43 this._sharedQueue.enqueue(task);
44
45 return;
46 }
47
48 let workerQueue = this._workerQueues[workerId];
49
50 if (workerQueue == null) {
51 workerQueue = this._workerQueues[workerId] = new InternalQueue();
52 }
53
54 const sharedTop = this._sharedQueue.peekLast();
55
56 const item = {
57 previousSharedTask: sharedTop,
58 task
59 };
60 workerQueue.enqueue(item);
61 }
62
63 dequeue(workerId) {
64 var _this$_workerQueues$w, _workerTop$previousSh, _workerTop$previousSh2;
65
66 const workerTop =
67 (_this$_workerQueues$w = this._workerQueues[workerId]) === null ||
68 _this$_workerQueues$w === void 0
69 ? void 0
70 : _this$_workerQueues$w.peek();
71 const sharedTaskIsProcessed =
72 (_workerTop$previousSh =
73 workerTop === null || workerTop === void 0
74 ? void 0
75 : (_workerTop$previousSh2 = workerTop.previousSharedTask) === null ||
76 _workerTop$previousSh2 === void 0
77 ? void 0
78 : _workerTop$previousSh2.request[1]) !== null &&
79 _workerTop$previousSh !== void 0
80 ? _workerTop$previousSh
81 : true; // Process the top task from the shared queue if
82 // - there's no task in the worker specific queue or
83 // - if the non-worker-specific task after which this worker specifif task
84 // hasn been queued wasn't processed yet
85
86 if (workerTop != null && sharedTaskIsProcessed) {
87 var _this$_workerQueues$w2,
88 _this$_workerQueues$w3,
89 _this$_workerQueues$w4;
90
91 return (_this$_workerQueues$w2 =
92 (_this$_workerQueues$w3 = this._workerQueues[workerId]) === null ||
93 _this$_workerQueues$w3 === void 0
94 ? void 0
95 : (_this$_workerQueues$w4 = _this$_workerQueues$w3.dequeue()) ===
96 null || _this$_workerQueues$w4 === void 0
97 ? void 0
98 : _this$_workerQueues$w4.task) !== null &&
99 _this$_workerQueues$w2 !== void 0
100 ? _this$_workerQueues$w2
101 : null;
102 }
103
104 return this._sharedQueue.dequeue();
105 }
106}
107
108exports.default = FifoQueue;
109
110/**
111 * FIFO queue for a single worker / shared queue.
112 */
113class InternalQueue {
114 constructor() {
115 _defineProperty(this, '_head', null);
116
117 _defineProperty(this, '_last', null);
118 }
119
120 enqueue(value) {
121 const item = {
122 next: null,
123 value
124 };
125
126 if (this._last == null) {
127 this._head = item;
128 } else {
129 this._last.next = item;
130 }
131
132 this._last = item;
133 }
134
135 dequeue() {
136 if (this._head == null) {
137 return null;
138 }
139
140 const item = this._head;
141 this._head = item.next;
142
143 if (this._head == null) {
144 this._last = null;
145 }
146
147 return item.value;
148 }
149
150 peek() {
151 var _this$_head$value, _this$_head;
152
153 return (_this$_head$value =
154 (_this$_head = this._head) === null || _this$_head === void 0
155 ? void 0
156 : _this$_head.value) !== null && _this$_head$value !== void 0
157 ? _this$_head$value
158 : null;
159 }
160
161 peekLast() {
162 var _this$_last$value, _this$_last;
163
164 return (_this$_last$value =
165 (_this$_last = this._last) === null || _this$_last === void 0
166 ? void 0
167 : _this$_last.value) !== null && _this$_last$value !== void 0
168 ? _this$_last$value
169 : null;
170 }
171}