tenfourfox/dom/apps/AppDownloadManager.jsm
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

105 lines
3.2 KiB
JavaScript

/* 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 file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
const Cc = Components.classes;
const Ci = Components.interfaces;
const Cu = Components.utils;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "FreeSpaceWatcher",
"resource://gre/modules/FreeSpaceWatcher.jsm");
this.EXPORTED_SYMBOLS = ["AppDownloadManager"];
function debug(aMsg) {
//dump("-*-*- AppDownloadManager.jsm : " + aMsg + "\n");
}
this.AppDownloadManager = {
// Minimum disk free space we want to keep, in bytes.
// Keep synchronized with Webapps.jsm
MIN_REMAINING_FREESPACE: 5 * 1024 * 1024,
downloads: {},
count: 0,
cancelFunc: null,
timer: null,
/**
* Registers the function called when we need to cancel a download.
* The function will be called with a single parameter being the
* manifest URL.
*/
registerCancelFunction: function app_dlMgr_registerCancel(aFunction) {
this.cancelFunc = aFunction;
},
/**
* Adds a download to the list of current downloads.
* @param aManifestURL The manifest URL for the application being downloaded.
* @param aDownload An opaque object representing the download.
*/
add: function app_dlMgr_add(aManifestURL, aDownload) {
debug("Adding " + aManifestURL);
if (!(aManifestURL in this.downloads)) {
this.count++;
if (this.count == 1) {
this.timer = FreeSpaceWatcher.create(this.MIN_REMAINING_FREESPACE,
this._spaceWatcher.bind(this));
}
}
this.downloads[aManifestURL] = aDownload;
},
/**
* Retrieves a download from the list of current downloads.
* @param aManifestURL The manifest URL for the application being retrieved.
* @return The opaque object representing the download.
*/
get: function app_dlMgr_get(aManifestURL) {
debug("Getting " + aManifestURL);
if (!this.downloads[aManifestURL]) {
return null;
}
return this.downloads[aManifestURL];
},
/**
* Removes a download of the list of current downloads.
* @param aManifestURL The manifest URL for the application being removed.
*/
remove: function app_dlMgr_remove(aManifestURL) {
debug("Removing " + aManifestURL);
if (aManifestURL in this.downloads) {
this.count--;
delete this.downloads[aManifestURL];
if (this.count == 0) {
FreeSpaceWatcher.stop(this.timer);
}
}
},
/**
* Callback for the free space watcher. This will call cancel on downloads
* if needed.
*/
_spaceWatcher: function app_dlMgr_watcher(aStatus) {
debug("Disk space is now " + aStatus);
if (aStatus == "free") {
// Nothing to do.
return;
}
// We cancel all downloads, because we don't know which ones we could
// keep running. We can improve that later if we have better heuristics,
// or when we'll support pause & resume we should just pause downloads.
for (let url in this.downloads) {
this.cancelFunc(url, "INSUFFICIENT_STORAGE");
}
}
}