/* 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/. */
// Enables logging and shorter save intervals.
const debugMode = false;
// Delay when a change is made to when the file is saved.
// 30 seconds normally, or 3 seconds for testing
const WRITE_DELAY_MS = (debugMode ? 3 : 30) * 1000;
const XULSTORE_CID = Components.ID("{6f46b6f4-c8b1-4bd4-a4fa-9ebbed0753ea}");
const STOREDB_FILENAME = "xulstore.json";
/**
* The XULStore retains XULElement attributes such as the sizing and styling. These are
* stored in the user's profile directory inside of "xulstore.json". The JSON is
* stored based on the chrome URL of the resource.
*
* For instance the "chrome://browser/content/browser.xhtml" main window sizing could be
* stored like so:
*
* {
* "chrome://browser/content/browser.xhtml": {
* "main-window": {
* "screenX": "1104",
* "screenY": "25",
* "width": "1904",
* "height": "1612",
* "sizemode": "normal"
* },
* ...
* }
* }
*
* The XULStore can only be loaded in the parent process. See the XULStore
* and XULPersist C++ classes for how this is integrated from the C++ side.
*/
export function XULStore() {
if (!Services.appinfo.inSafeMode) {
this.load();
}
}
XULStore.prototype = {
classID: XULSTORE_CID,
name: "XULStore",
QueryInterface: ChromeUtils.generateQI([
"nsINamed",
"nsIObserver",
"nsIXULStore",
"nsISupportsWeakReference",
]),
/* ---------- private members ---------- */
/*
* The format of _data is _data[docuri][elementid][attribute]. For example:
* {
* "chrome://blah/foo.xul" : {
* "main-window" : { aaa : 1, bbb : "c" },
* "barColumn" : { ddd : 9, eee : "f" },
* },
*
* "chrome://foopy/b.xul" : { ... },
* ...
* }
*/
_data: {},
_storeFile: null,
_needsSaving: false,
_saveAllowed: true,
_writeTimer: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
load() {
Services.obs.addObserver(this, "profile-before-change", true);
try {
this._storeFile = Services.dirsvc.get("ProfD", Ci.nsIFile);
} catch (ex) {
try {
this._storeFile = Services.dirsvc.get("ProfDS", Ci.nsIFile);
} catch (ex) {
throw new Error("Can't find profile directory.");
}
}
this._storeFile.append(STOREDB_FILENAME);
this.readFile();
},
observe(subject, topic) {
this.writeFile();
if (topic == "profile-before-change") {
this._saveAllowed = false;
}
},
/*
* Internal function for logging debug messages to the Error Console window
*/
log(message) {
if (!debugMode) {
return;
}
console.log("XULStore: " + message);
},
readFile() {
try {
this._data = JSON.parse(Cu.readUTF8File(this._storeFile));
} catch (e) {
this.log("Error reading JSON: " + e);
// This exception could mean that the file didn't exist.
// We'll just ignore the error and start with a blank slate.
}
},
async writeFile() {
if (!this._needsSaving) {
return;
}
this._needsSaving = false;
this.log("Writing to xulstore.json");
try {
await IOUtils.writeJSON(this._storeFile.path, this._data, {
tmpPath: this._storeFile.path + ".tmp",
});
} catch (e) {
this.log("Failed to write xulstore.json: " + e);
throw e;
}
},
markAsChanged() {
if (this._needsSaving || !this._storeFile) {
return;
}
// Don't write the file more than once every 30 seconds.
this._needsSaving = true;
this._writeTimer.init(this, WRITE_DELAY_MS, Ci.nsITimer.TYPE_ONE_SHOT);
},
/* ---------- interface implementation ---------- */
persist(node, attr) {
if (!node.id) {
throw new Error("Node without ID passed into persist()");
}
const uri = node.ownerDocument.documentURI;
const value = node.getAttribute(attr) || "";
if (node.localName == "window") {
this.log("Persisting attributes to windows is handled by AppWindow.");
return;
}
// See Bug 1476680 - we could drop the `hasValue` check so that
// any time there's an empty attribute it gets removed from the
// store. Since this is copying behavior from document.persist,
// callers would need to be updated with that change.
if (!value && this.hasValue(uri, node.id, attr)) {
this.removeValue(uri, node.id, attr);
} else {
this.setValue(uri, node.id, attr, value);
}
},
setValue(docURI, id, attr, value) {
this.log(
"Saving " + attr + "=" + value + " for id=" + id + ", doc=" + docURI
);
if (!this._saveAllowed) {
Services.console.logStringMessage(
"XULStore: Changes after profile-before-change are ignored!"
);
return;
}
// bug 319846 -- don't save really long attributes or values.
if (id.length > 512 || attr.length > 512) {
throw Components.Exception(
"id or attribute name too long",
Cr.NS_ERROR_ILLEGAL_VALUE
);
}
if (value.length > 4096) {
Services.console.logStringMessage(
"XULStore: Warning, truncating long attribute value"
);
value = value.substr(0, 4096);
}
let obj = this._data;
if (!(docURI in obj)) {
obj[docURI] = {};
}
obj = obj[docURI];
if (!(id in obj)) {
obj[id] = {};
}
obj = obj[id];
// Don't set the value if it is already set to avoid saving the file.
if (attr in obj && obj[attr] == value) {
return;
}
obj[attr] = value; // IE, this._data[docURI][id][attr] = value;
this.markAsChanged();
},
hasValue(docURI, id, attr) {
this.log(
"has store value for id=" + id + ", attr=" + attr + ", doc=" + docURI
);
let ids = this._data[docURI];
if (ids) {
let attrs = ids[id];
if (attrs) {
return attr in attrs;
}
}
return false;
},
getValue(docURI, id, attr) {
this.log(
"get store value for id=" + id + ", attr=" + attr + ", doc=" + docURI
);
let ids = this._data[docURI];
if (ids) {
let attrs = ids[id];
if (attrs) {
return attrs[attr] || "";
}
}
return "";
},
removeValue(docURI, id, attr) {
this.log(
"remove store value for id=" + id + ", attr=" + attr + ", doc=" + docURI
);
if (!this._saveAllowed) {
Services.console.logStringMessage(
"XULStore: Changes after profile-before-change are ignored!"
);
return;
}
let ids = this._data[docURI];
if (ids) {
let attrs = ids[id];
if (attrs && attr in attrs) {
delete attrs[attr];
if (!Object.getOwnPropertyNames(attrs).length) {
delete ids[id];
if (!Object.getOwnPropertyNames(ids).length) {
delete this._data[docURI];
}
}
this.markAsChanged();
}
}
},
removeDocument(docURI) {
this.log("remove store values for doc=" + docURI);
if (!this._saveAllowed) {
Services.console.logStringMessage(
"XULStore: Changes after profile-before-change are ignored!"
);
return;
}
if (this._data[docURI]) {
delete this._data[docURI];
this.markAsChanged();
}
},
getIDsEnumerator(docURI) {
this.log("Getting ID enumerator for doc=" + docURI);
if (!(docURI in this._data)) {
return new nsStringEnumerator([]);
}
let result = [];
let ids = this._data[docURI];
if (ids) {
for (let id in this._data[docURI]) {
result.push(id);
}
}
return new nsStringEnumerator(result);
},
getAttributeEnumerator(docURI, id) {
this.log("Getting attribute enumerator for id=" + id + ", doc=" + docURI);
if (!(docURI in this._data) || !(id in this._data[docURI])) {
return new nsStringEnumerator([]);
}
let attrs = [];
for (let attr in this._data[docURI][id]) {
attrs.push(attr);
}
return new nsStringEnumerator(attrs);
},
};
function nsStringEnumerator(items) {
this._items = items;
}
nsStringEnumerator.prototype = {
QueryInterface: ChromeUtils.generateQI(["nsIStringEnumerator"]),
_nextIndex: 0,
[Symbol.iterator]() {
return this._items.values();
},
hasMore() {
return this._nextIndex < this._items.length;
},
getNext() {
if (!this.hasMore()) {
throw Components.Exception("", Cr.NS_ERROR_NOT_AVAILABLE);
}
return this._items[this._nextIndex++];
},
};
