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1 | 1 | 'use strict'; |
2 | 2 |
|
3 | | -exports.setup = setupNextTick; |
4 | | - |
5 | | -function setupNextTick(_setupNextTick, _setupPromises) { |
6 | | - const { |
7 | | - getDefaultTriggerAsyncId, |
8 | | - newAsyncId, |
9 | | - initHooksExist, |
10 | | - destroyHooksExist, |
11 | | - emitInit, |
12 | | - emitBefore, |
13 | | - emitAfter, |
14 | | - emitDestroy, |
15 | | - symbols: { async_id_symbol, trigger_async_id_symbol } |
16 | | - } = require('internal/async_hooks'); |
17 | | - const emitPromiseRejectionWarnings = |
18 | | - require('internal/process/promises').setup(_setupPromises); |
19 | | - const { ERR_INVALID_CALLBACK } = require('internal/errors').codes; |
20 | | - const FixedQueue = require('internal/fixed_queue'); |
21 | | - |
22 | | - // tickInfo is used so that the C++ code in src/node.cc can |
23 | | - // have easy access to our nextTick state, and avoid unnecessary |
24 | | - // calls into JS land. |
25 | | - // runMicrotasks is used to run V8's micro task queue. |
26 | | - const [ |
27 | | - tickInfo, |
28 | | - runMicrotasks |
29 | | - ] = _setupNextTick(internalTickCallback); |
30 | | - |
31 | | - // *Must* match Environment::TickInfo::Fields in src/env.h. |
32 | | - const kHasScheduled = 0; |
33 | | - const kHasPromiseRejections = 1; |
34 | | - |
35 | | - const queue = new FixedQueue(); |
36 | | - |
37 | | - process.nextTick = nextTick; |
38 | | - // Needs to be accessible from beyond this scope. |
39 | | - process._tickCallback = _tickCallback; |
40 | | - |
41 | | - function _tickCallback() { |
42 | | - if (tickInfo[kHasScheduled] === 0 && tickInfo[kHasPromiseRejections] === 0) |
43 | | - runMicrotasks(); |
44 | | - if (tickInfo[kHasScheduled] === 0 && tickInfo[kHasPromiseRejections] === 0) |
45 | | - return; |
46 | | - |
47 | | - internalTickCallback(); |
48 | | - } |
49 | | - |
50 | | - function internalTickCallback() { |
51 | | - let tock; |
52 | | - do { |
53 | | - while (tock = queue.shift()) { |
54 | | - const asyncId = tock[async_id_symbol]; |
55 | | - emitBefore(asyncId, tock[trigger_async_id_symbol]); |
56 | | - // emitDestroy() places the async_id_symbol into an asynchronous queue |
57 | | - // that calls the destroy callback in the future. It's called before |
58 | | - // calling tock.callback so destroy will be called even if the callback |
59 | | - // throws an exception that is handled by 'uncaughtException' or a |
60 | | - // domain. |
61 | | - // TODO(trevnorris): This is a bit of a hack. It relies on the fact |
62 | | - // that nextTick() doesn't allow the event loop to proceed, but if |
63 | | - // any async hooks are enabled during the callback's execution then |
64 | | - // this tock's after hook will be called, but not its destroy hook. |
65 | | - if (destroyHooksExist()) |
66 | | - emitDestroy(asyncId); |
67 | | - |
68 | | - const callback = tock.callback; |
69 | | - if (tock.args === undefined) |
70 | | - callback(); |
71 | | - else |
72 | | - Reflect.apply(callback, undefined, tock.args); |
73 | | - |
74 | | - emitAfter(asyncId); |
75 | | - } |
76 | | - tickInfo[kHasScheduled] = 0; |
77 | | - runMicrotasks(); |
78 | | - } while (!queue.isEmpty() || emitPromiseRejectionWarnings()); |
79 | | - tickInfo[kHasPromiseRejections] = 0; |
80 | | - } |
| 3 | +const { |
| 4 | + // For easy access to the nextTick state in the C++ land, |
| 5 | + // and to avoid unnecessary calls into JS land. |
| 6 | + tickInfo, |
| 7 | + // Used to run V8's micro task queue. |
| 8 | + runMicrotasks, |
| 9 | + setTickCallback, |
| 10 | + initializePromiseRejectCallback |
| 11 | +} = internalBinding('task_queue'); |
| 12 | + |
| 13 | +const { |
| 14 | + promiseRejectHandler, |
| 15 | + emitPromiseRejectionWarnings |
| 16 | +} = require('internal/process/promises'); |
| 17 | + |
| 18 | +const { |
| 19 | + getDefaultTriggerAsyncId, |
| 20 | + newAsyncId, |
| 21 | + initHooksExist, |
| 22 | + destroyHooksExist, |
| 23 | + emitInit, |
| 24 | + emitBefore, |
| 25 | + emitAfter, |
| 26 | + emitDestroy, |
| 27 | + symbols: { async_id_symbol, trigger_async_id_symbol } |
| 28 | +} = require('internal/async_hooks'); |
| 29 | +const { ERR_INVALID_CALLBACK } = require('internal/errors').codes; |
| 30 | +const FixedQueue = require('internal/fixed_queue'); |
| 31 | + |
| 32 | +// *Must* match Environment::TickInfo::Fields in src/env.h. |
| 33 | +const kHasScheduled = 0; |
| 34 | +const kHasPromiseRejections = 1; |
| 35 | + |
| 36 | +const queue = new FixedQueue(); |
| 37 | + |
| 38 | +function runNextTicks() { |
| 39 | + if (tickInfo[kHasScheduled] === 0 && tickInfo[kHasPromiseRejections] === 0) |
| 40 | + runMicrotasks(); |
| 41 | + if (tickInfo[kHasScheduled] === 0 && tickInfo[kHasPromiseRejections] === 0) |
| 42 | + return; |
| 43 | + |
| 44 | + internalTickCallback(); |
| 45 | +} |
81 | 46 |
|
82 | | - class TickObject { |
83 | | - constructor(callback, args, triggerAsyncId) { |
84 | | - // This must be set to null first to avoid function tracking |
85 | | - // on the hidden class, revisit in V8 versions after 6.2 |
86 | | - this.callback = null; |
87 | | - this.callback = callback; |
88 | | - this.args = args; |
89 | | - |
90 | | - const asyncId = newAsyncId(); |
91 | | - this[async_id_symbol] = asyncId; |
92 | | - this[trigger_async_id_symbol] = triggerAsyncId; |
93 | | - |
94 | | - if (initHooksExist()) { |
95 | | - emitInit(asyncId, |
96 | | - 'TickObject', |
97 | | - triggerAsyncId, |
98 | | - this); |
99 | | - } |
| 47 | +function internalTickCallback() { |
| 48 | + let tock; |
| 49 | + do { |
| 50 | + while (tock = queue.shift()) { |
| 51 | + const asyncId = tock[async_id_symbol]; |
| 52 | + emitBefore(asyncId, tock[trigger_async_id_symbol]); |
| 53 | + // emitDestroy() places the async_id_symbol into an asynchronous queue |
| 54 | + // that calls the destroy callback in the future. It's called before |
| 55 | + // calling tock.callback so destroy will be called even if the callback |
| 56 | + // throws an exception that is handled by 'uncaughtException' or a |
| 57 | + // domain. |
| 58 | + // TODO(trevnorris): This is a bit of a hack. It relies on the fact |
| 59 | + // that nextTick() doesn't allow the event loop to proceed, but if |
| 60 | + // any async hooks are enabled during the callback's execution then |
| 61 | + // this tock's after hook will be called, but not its destroy hook. |
| 62 | + if (destroyHooksExist()) |
| 63 | + emitDestroy(asyncId); |
| 64 | + |
| 65 | + const callback = tock.callback; |
| 66 | + if (tock.args === undefined) |
| 67 | + callback(); |
| 68 | + else |
| 69 | + Reflect.apply(callback, undefined, tock.args); |
| 70 | + |
| 71 | + emitAfter(asyncId); |
100 | 72 | } |
101 | | - } |
| 73 | + tickInfo[kHasScheduled] = 0; |
| 74 | + runMicrotasks(); |
| 75 | + } while (!queue.isEmpty() || emitPromiseRejectionWarnings()); |
| 76 | + tickInfo[kHasPromiseRejections] = 0; |
| 77 | +} |
102 | 78 |
|
103 | | - // `nextTick()` will not enqueue any callback when the process is about to |
104 | | - // exit since the callback would not have a chance to be executed. |
105 | | - function nextTick(callback) { |
106 | | - if (typeof callback !== 'function') |
107 | | - throw new ERR_INVALID_CALLBACK(); |
108 | | - |
109 | | - if (process._exiting) |
110 | | - return; |
111 | | - |
112 | | - var args; |
113 | | - switch (arguments.length) { |
114 | | - case 1: break; |
115 | | - case 2: args = [arguments[1]]; break; |
116 | | - case 3: args = [arguments[1], arguments[2]]; break; |
117 | | - case 4: args = [arguments[1], arguments[2], arguments[3]]; break; |
118 | | - default: |
119 | | - args = new Array(arguments.length - 1); |
120 | | - for (var i = 1; i < arguments.length; i++) |
121 | | - args[i - 1] = arguments[i]; |
| 79 | +class TickObject { |
| 80 | + constructor(callback, args, triggerAsyncId) { |
| 81 | + // This must be set to null first to avoid function tracking |
| 82 | + // on the hidden class, revisit in V8 versions after 6.2 |
| 83 | + this.callback = null; |
| 84 | + this.callback = callback; |
| 85 | + this.args = args; |
| 86 | + |
| 87 | + const asyncId = newAsyncId(); |
| 88 | + this[async_id_symbol] = asyncId; |
| 89 | + this[trigger_async_id_symbol] = triggerAsyncId; |
| 90 | + |
| 91 | + if (initHooksExist()) { |
| 92 | + emitInit(asyncId, |
| 93 | + 'TickObject', |
| 94 | + triggerAsyncId, |
| 95 | + this); |
122 | 96 | } |
| 97 | + } |
| 98 | +} |
123 | 99 |
|
124 | | - if (queue.isEmpty()) |
125 | | - tickInfo[kHasScheduled] = 1; |
126 | | - queue.push(new TickObject(callback, args, getDefaultTriggerAsyncId())); |
| 100 | +// `nextTick()` will not enqueue any callback when the process is about to |
| 101 | +// exit since the callback would not have a chance to be executed. |
| 102 | +function nextTick(callback) { |
| 103 | + if (typeof callback !== 'function') |
| 104 | + throw new ERR_INVALID_CALLBACK(); |
| 105 | + |
| 106 | + if (process._exiting) |
| 107 | + return; |
| 108 | + |
| 109 | + var args; |
| 110 | + switch (arguments.length) { |
| 111 | + case 1: break; |
| 112 | + case 2: args = [arguments[1]]; break; |
| 113 | + case 3: args = [arguments[1], arguments[2]]; break; |
| 114 | + case 4: args = [arguments[1], arguments[2], arguments[3]]; break; |
| 115 | + default: |
| 116 | + args = new Array(arguments.length - 1); |
| 117 | + for (var i = 1; i < arguments.length; i++) |
| 118 | + args[i - 1] = arguments[i]; |
127 | 119 | } |
| 120 | + |
| 121 | + if (queue.isEmpty()) |
| 122 | + tickInfo[kHasScheduled] = 1; |
| 123 | + queue.push(new TickObject(callback, args, getDefaultTriggerAsyncId())); |
128 | 124 | } |
| 125 | + |
| 126 | +// TODO(joyeecheung): make this a factory class so that node.js can |
| 127 | +// control the side effects caused by the initializers. |
| 128 | +exports.setup = function() { |
| 129 | + // Initializes the per-isolate promise rejection callback which |
| 130 | + // will call the handler being passed into this function. |
| 131 | + initializePromiseRejectCallback(promiseRejectHandler); |
| 132 | + // Sets the callback to be run in every tick. |
| 133 | + setTickCallback(internalTickCallback); |
| 134 | + return { |
| 135 | + nextTick, |
| 136 | + runNextTicks |
| 137 | + }; |
| 138 | +}; |
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