michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: "use strict";
michael@0: 
michael@0: module.metadata = {
michael@0:   "stability": "deprecated"
michael@0: };
michael@0: 
michael@0: const { Cc, Ci, Cu, components } = require("chrome");
michael@0: const { when: unload } = require("../system/unload")
michael@0: 
michael@0: var trackedObjects = {};
michael@0: const Compacter = {
michael@0:   notify: function() {
michael@0:     var newTrackedObjects = {};
michael@0: 
michael@0:     for (let name in trackedObjects) {
michael@0:       let oldBin = trackedObjects[name];
michael@0:       let newBin = [];
michael@0:       let strongRefs = [];
michael@0: 
michael@0:       for (let i = 0, l = oldBin.length; i < l; i++) {
michael@0:         let strongRef = oldBin[i].weakref.get();
michael@0: 
michael@0:         if (strongRef && strongRefs.indexOf(strongRef) == -1) {
michael@0:           strongRefs.push(strongRef);
michael@0:           newBin.push(oldBin[i]);
michael@0:         }
michael@0:       }
michael@0: 
michael@0:       if (newBin.length)
michael@0:         newTrackedObjects[name] = newBin;
michael@0:     }
michael@0: 
michael@0:     trackedObjects = newTrackedObjects;
michael@0:   }
michael@0: };
michael@0: 
michael@0: var timer = Cc["@mozilla.org/timer;1"]
michael@0:             .createInstance(Ci.nsITimer);
michael@0: timer.initWithCallback(Compacter,
michael@0:                        5000,
michael@0:                        Ci.nsITimer.TYPE_REPEATING_SLACK);
michael@0: 
michael@0: function track(object, bin, stackFrameNumber) {
michael@0:   var frame = components.stack.caller;
michael@0:   var weakref = Cu.getWeakReference(object);
michael@0: 
michael@0:   if (!bin && 'constructor' in object)
michael@0:     bin = object.constructor.name;
michael@0:   if (bin == "Object")
michael@0:     bin = frame.name;
michael@0:   if (!bin)
michael@0:     bin = "generic";
michael@0:   if (!(bin in trackedObjects))
michael@0:     trackedObjects[bin] = [];
michael@0: 
michael@0:   if (stackFrameNumber > 0)
michael@0:     for (var i = 0; i < stackFrameNumber; i++)
michael@0:       frame = frame.caller;
michael@0: 
michael@0:   trackedObjects[bin].push({weakref: weakref,
michael@0:                             created: new Date(),
michael@0:                             filename: frame.filename,
michael@0:                             lineNo: frame.lineNumber,
michael@0:                             bin: bin});
michael@0: }
michael@0: exports.track = track;
michael@0: 
michael@0: var getBins = exports.getBins = function getBins() {
michael@0:   var names = [];
michael@0:   for (let name in trackedObjects)
michael@0:     names.push(name);
michael@0:   return names;
michael@0: };
michael@0: 
michael@0: function getObjects(bin) {
michael@0:   var results = [];
michael@0: 
michael@0:   function getLiveObjectsInBin(bin) {
michael@0:     for (let i = 0, l = bin.length; i < l; i++) {
michael@0:       let object = bin[i].weakref.get();
michael@0: 
michael@0:       if (object) {
michael@0:         results.push(bin[i]);
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   if (bin) {
michael@0:     if (bin in trackedObjects)
michael@0:       getLiveObjectsInBin(trackedObjects[bin]);
michael@0:   }
michael@0:   else {
michael@0:     for (let name in trackedObjects)
michael@0:       getLiveObjectsInBin(trackedObjects[name]);
michael@0:   }
michael@0: 
michael@0:   return results;
michael@0: }
michael@0: exports.getObjects = getObjects;
michael@0: 
michael@0: function gc() {
michael@0:   // Components.utils.forceGC() doesn't currently perform
michael@0:   // cycle collection, which means that e.g. DOM elements
michael@0:   // won't be collected by it. Fortunately, there are
michael@0:   // other ways...
michael@0:   var test_utils = Cc["@mozilla.org/appshell/appShellService;1"]
michael@0:                .getService(Ci.nsIAppShellService)
michael@0:                .hiddenDOMWindow
michael@0:                .QueryInterface(Ci.nsIInterfaceRequestor)
michael@0:                .getInterface(Ci.nsIDOMWindowUtils);
michael@0:   test_utils.garbageCollect();
michael@0:   // Clean metadata for dead objects
michael@0:   Compacter.notify();
michael@0:   // Not sure why, but sometimes it appears that we don't get
michael@0:   // them all with just one CC, so let's do it again.
michael@0:   test_utils.garbageCollect();
michael@0: };
michael@0: exports.gc = gc;
michael@0: 
michael@0: unload(_ => {
michael@0:   trackedObjects = {};
michael@0:   if (timer) {
michael@0:     timer.cancel();
michael@0:     timer = null;
michael@0:   }
michael@0: });