src: add C++ support for diagnostics channels · nodejs/node@46ee1ed

const { triggerUncaughtException } = internalBinding('errors');

const dc_binding = internalBinding('diagnostics_channel');

const { subscribers: subscriberCounts } = dc_binding;

const { WeakReference } = require('internal/util');

// Can't delete when weakref count reaches 0 as it could increment again.

this._subscribers = ArrayPrototypeSlice(this._subscribers);

ArrayPrototypePush(this._subscribers, subscription);

channels.incRef(this.name);

if (this._index !== undefined) subscriberCounts[this._index]++;

}

unsubscribe(subscription) {

ArrayPrototypePushApply(this._subscribers, after);

channels.decRef(this.name);

if (this._index !== undefined) subscriberCounts[this._index]--;

maybeMarkInactive(this);

return true;

}

bindStore(store, transform) {

const replacing = this._stores.has(store);

if (!replacing) channels.incRef(this.name);

if (!replacing) {

channels.incRef(this.name);

if (this._index !== undefined) subscriberCounts[this._index]++;

}

this._stores.set(store, transform);

}

this._stores.delete(store);

channels.decRef(this.name);

if (this._index !== undefined) subscriberCounts[this._index]--;

maybeMarkInactive(this);

return true;

this._subscribers = undefined;

this._stores = undefined;

this.name = name;

if (typeof name === 'string') {

this._index = dc_binding.getOrCreateChannelIndex(name);

}

channels.set(name, this);

}

return new TracingChannel(nameOrChannels);

}

dc_binding.linkNativeChannel((name) => channel(name));

module.exports = {

channel,

hasSubscribers,