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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* A connection between app-services tracing-support library and Firefox.
*
* Used by logging and other diagnostic support from app-services Rust components.
*/
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
// eslint-disable-next-line mozilla/use-console-createInstance
Log: "resource://gre/modules/Log.sys.mjs",
});
import {
registerEventSink,
unregisterEventSink,
EventSink,
TracingLevel,
} from "moz-src:///toolkit/components/uniffi-bindgen-gecko-js/components/generated/RustTracing.sys.mjs";
ChromeUtils.defineLazyGetter(lazy, "console", () =>
console.createInstance({
prefix: "AppServices",
// maxLogLevelPref: "toolkit.appservicestracing.loglevel"
})
);
/** A singleton uniffi callback interface. */
class TracingEventHandler extends EventSink {
static OBSERVER_NAME = "xpcom-will-shutdown";
constructor() {
super();
this.registeredTargets = new Map();
Services.obs.addObserver(this, TracingEventHandler.OBSERVER_NAME);
}
register(target, level, callback) {
if (this.registeredTargets === null) {
lazy.console.trace(
"ignoring attempt to register event handler after shutdown has commenced"
);
return;
}
if (!this.registeredTargets.has(target)) {
this.registeredTargets.set(target, { level, callbacks: [callback] });
registerEventSink(target, level, this);
} else {
let { level: existingLevel, callbacks } =
this.registeredTargets.get(target);
callbacks.push(callback);
// if the new verbosity is greater we must re-register.
if (level > existingLevel) {
lazy.console.trace("re-registering as new level more verbose");
registerEventSink(target, level, this);
}
}
}
onEvent(event) {
let target = targetRoot(event.target);
let callbackRecord = this.registeredTargets.get(target);
if (callbackRecord) {
for (let callback of callbackRecord.callbacks) {
try {
callback(event);
} catch (e) {
lazy.console.error("tracing callback failed", callback, e);
}
}
} else {
lazy.console.error("event callback without a handler");
}
}
observe(_aSubject, aTopic, _aData) {
if (aTopic == TracingEventHandler.OBSERVER_NAME) {
for (let target of this.registeredTargets.keys()) {
unregisterEventSink(target);
}
this.registeredTargets = null;
}
}
}
// the singleton.
let tracingEventHandler = new TracingEventHandler();
// helper to get the pre '::' part of the target.
function targetRoot(target) {
let colonIndex = target.indexOf(":");
if (colonIndex > 0) {
return target.slice(0, colonIndex);
}
return target;
}
/*
* Log.sys.mjs adaptor.
* Converts tracing log events to Log calls.
*/
// each target may go to one or more logs.
let targetToLogNames = new Map();
// handles a logging event we previously registered for.
function loggerEventHandler(event) {
let target = targetRoot(event.target);
for (const name of targetToLogNames.get(target) || []) {
let log = lazy.Log.repository.getLogger(name);
let log_level;
if (event.level == TracingLevel.Debug) {
log_level = lazy.Log.Level.Debug;
} else if (event.level == TracingLevel.Info) {
log_level = lazy.Log.Level.Info;
} else if (event.level == TracingLevel.Warn) {
log_level = lazy.Log.Level.Warn;
} else {
log_level = lazy.Log.Level.Error;
}
log.log(log_level, event.message);
}
}
/**
* send output from a target to a Log.sys.jsm logger.
*/
export function setupLoggerForTarget(target, log) {
if (typeof log == "string") {
log = lazy.Log.repository.getLogger(log);
}
let log_level = log.level;
let tracing_level;
if (log_level == lazy.Log.ERROR) {
tracing_level = TracingLevel.ERROR;
} else if (log_level == lazy.Log.WARN) {
tracing_level = TracingLevel.WARN;
} else if (log_level == lazy.Log.INFO) {
tracing_level = TracingLevel.INFO;
} else if (log_level == lazy.Log.DEBUG) {
tracing_level = TracingLevel.DEBUG;
} else {
tracing_level = TracingLevel.TRACE;
}
targetToLogNames.set(target, log.name);
tracingEventHandler.register(target, tracing_level, loggerEventHandler);
}