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+/* vim:set ts=2 sw=2 sts=2 expandtab */
+/* 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/.
+ */
+;(function(id, factory) { // Module boilerplate :(
+ if (typeof(define) === 'function') { // RequireJS
+ define(factory);
+ } else if (typeof(require) === 'function') { // CommonJS
+ factory.call(this, require, exports, module);
+ } else if (~String(this).indexOf('BackstagePass')) { // JSM
+ factory(function require(uri) {
+ var imports = {};
+ this['Components'].utils.import(uri, imports);
+ return imports;
+ }, this, { uri: __URI__, id: id });
+ this.EXPORTED_SYMBOLS = Object.keys(this);
+ } else if (~String(this).indexOf('Sandbox')) { // Sandbox
+ factory(function require(uri) {}, this, { uri: __URI__, id: id });
+ } else { // Browser or alike
+ var globals = this
+ factory(function require(id) {
+ return globals[id];
+ }, (globals[id] = {}), { uri: document.location.href + '#' + id, id: id });
+ }
+}).call(this, 'loader', function(require, exports, module) {
+
+'use strict';
+
+module.metadata = {
+ "stability": "unstable"
+};
+
+const { classes: Cc, Constructor: CC, interfaces: Ci, utils: Cu,
+ results: Cr, manager: Cm } = Components;
+const systemPrincipal = CC('@mozilla.org/systemprincipal;1', 'nsIPrincipal')();
+const { loadSubScript } = Cc['@mozilla.org/moz/jssubscript-loader;1'].
+ getService(Ci.mozIJSSubScriptLoader);
+const { notifyObservers } = Cc['@mozilla.org/observer-service;1'].
+ getService(Ci.nsIObserverService);
+
+// Define some shortcuts.
+const bind = Function.call.bind(Function.bind);
+const getOwnPropertyNames = Object.getOwnPropertyNames;
+const getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;
+const define = Object.defineProperties;
+const prototypeOf = Object.getPrototypeOf;
+const create = Object.create;
+const keys = Object.keys;
+
+// Workaround for bug 674195. Freezing objects from other compartments fail,
+// so we use `Object.freeze` from the same component instead.
+function freeze(object) {
+ if (prototypeOf(object) === null) {
+ Object.freeze(object);
+ }
+ else {
+ prototypeOf(prototypeOf(object.isPrototypeOf)).
+ constructor. // `Object` from the owner compartment.
+ freeze(object);
+ }
+ return object;
+}
+
+// Returns map of given `object`-s own property descriptors.
+const descriptor = iced(function descriptor(object) {
+ let value = {};
+ getOwnPropertyNames(object).forEach(function(name) {
+ value[name] = getOwnPropertyDescriptor(object, name)
+ });
+ return value;
+});
+exports.descriptor = descriptor;
+
+// Freeze important built-ins so they can't be used by untrusted code as a
+// message passing channel.
+freeze(Object);
+freeze(Object.prototype);
+freeze(Function);
+freeze(Function.prototype);
+freeze(Array);
+freeze(Array.prototype);
+freeze(String);
+freeze(String.prototype);
+
+// This function takes `f` function sets it's `prototype` to undefined and
+// freezes it. We need to do this kind of deep freeze with all the exposed
+// functions so that untrusted code won't be able to use them a message
+// passing channel.
+function iced(f) {
+ f.prototype = undefined;
+ return freeze(f);
+}
+
+// Defines own properties of given `properties` object on the given
+// target object overriding any existing property with a conflicting name.
+// Returns `target` object. Note we only export this function because it's
+// useful during loader bootstrap when other util modules can't be used &
+// thats only case where this export should be used.
+const override = iced(function override(target, source) {
+ let properties = descriptor(target)
+ let extension = descriptor(source || {})
+ getOwnPropertyNames(extension).forEach(function(name) {
+ properties[name] = extension[name];
+ });
+ return define({}, properties);
+});
+exports.override = override;
+
+// Function takes set of options and returns a JS sandbox. Function may be
+// passed set of options:
+// - `name`: A string value which identifies the sandbox in about:memory. Will
+// throw exception if omitted.
+// - `principal`: String URI or `nsIPrincipal` for the sandbox. Defaults to
+// system principal.
+// - `prototype`: Ancestor for the sandbox that will be created. Defaults to
+// `{}`.
+// - `wantXrays`: A Boolean value indicating whether code outside the sandbox
+// wants X-ray vision with respect to objects inside the sandbox. Defaults
+// to `true`.
+// - `sandbox`: A sandbox to share JS compartment with. If omitted new
+// compartment will be created.
+// For more details see:
+// https://developer.mozilla.org/en/Components.utils.Sandbox
+const Sandbox = iced(function Sandbox(options) {
+ // Normalize options and rename to match `Cu.Sandbox` expectations.
+ options = {
+ // Do not expose `Components` if you really need them (bad idea!) you
+ // still can expose via prototype.
+ wantComponents: false,
+ sandboxName: options.name,
+ principal: 'principal' in options ? options.principal : systemPrincipal,
+ wantXrays: 'wantXrays' in options ? options.wantXrays : true,
+ sandboxPrototype: 'prototype' in options ? options.prototype : {},
+ sameGroupAs: 'sandbox' in options ? options.sandbox : null
+ };
+
+ // Make `options.sameGroupAs` only if `sandbox` property is passed,
+ // otherwise `Cu.Sandbox` will throw.
+ if (!options.sameGroupAs)
+ delete options.sameGroupAs;
+
+ let sandbox = Cu.Sandbox(options.principal, options);
+
+ // Each sandbox at creation gets set of own properties that will be shadowing
+ // ones from it's prototype. We override delete such `sandbox` properties
+ // to avoid shadowing.
+ delete sandbox.Iterator;
+ delete sandbox.Components;
+ delete sandbox.importFunction;
+ delete sandbox.debug;
+
+ return sandbox;
+});
+exports.Sandbox = Sandbox;
+
+// Evaluates code from the given `uri` into given `sandbox`. If
+// `options.source` is passed, then that code is evaluated instead.
+// Optionally following options may be given:
+// - `options.encoding`: Source encoding, defaults to 'UTF-8'.
+// - `options.line`: Line number to start count from for stack traces.
+// Defaults to 1.
+// - `options.version`: Version of JS used, defaults to '1.8'.
+const evaluate = iced(function evaluate(sandbox, uri, options) {
+ let { source, line, version, encoding } = override({
+ encoding: 'UTF-8',
+ line: 1,
+ version: '1.8',
+ source: null
+ }, options);
+
+
+ return source ? Cu.evalInSandbox(source, sandbox, version, uri, line)
+ : loadSubScript(uri, sandbox, encoding);
+});
+exports.evaluate = evaluate;
+
+// Populates `exports` of the given CommonJS `module` object, in the context
+// of the given `loader` by evaluating code associated with it.
+const load = iced(function load(loader, module) {
+ let { sandboxes, globals } = loader;
+ let require = Require(loader, module);
+
+ let sandbox = sandboxes[module.uri] = Sandbox({
+ name: module.uri,
+ // Get an existing module sandbox, if any, so we can reuse its compartment
+ // when creating the new one to reduce memory consumption.
+ sandbox: sandboxes[keys(sandboxes).shift()],
+ // We expose set of properties defined by `CommonJS` specification via
+ // prototype of the sandbox. Also globals are deeper in the prototype
+ // chain so that each module has access to them as well.
+ prototype: create(globals, descriptor({
+ require: require,
+ module: module,
+ exports: module.exports
+ })),
+ wantXrays: false
+ });
+
+ evaluate(sandbox, module.uri);
+
+ if (module.exports && typeof(module.exports) === 'object')
+ freeze(module.exports);
+
+ return module;
+});
+exports.load = load;
+
+// Utility function to check if id is relative.
+function isRelative(id) { return id[0] === '.'; }
+// Utility function to normalize module `uri`s so they have `.js` extension.
+function normalize(uri) { return uri.substr(-3) === '.js' ? uri : uri + '.js'; }
+// Utility function to join paths. In common case `base` is a
+// `requirer.uri` but in some cases it may be `baseURI`. In order to
+// avoid complexity we require `baseURI` with a trailing `/`.
+const resolve = iced(function resolve(id, base) {
+ let paths = id.split('/');
+ let result = base.split('/');
+ result.pop();
+ while (paths.length) {
+ let path = paths.shift();
+ if (path === '..')
+ result.pop();
+ else if (path !== '.')
+ result.push(path);
+ }
+ return result.join('/');
+});
+exports.resolve = resolve;
+
+const resolveURI = iced(function resolveURI(id, mapping) {
+ let count = mapping.length, index = 0;
+ while (index < count) {
+ let [ path, uri ] = mapping[index ++];
+ if (id.indexOf(path) === 0)
+ return normalize(id.replace(path, uri));
+ }
+});
+exports.resolveURI = resolveURI;
+
+// Creates version of `require` that will be exposed to the given `module`
+// in the context of the given `loader`. Each module gets own limited copy
+// of `require` that is allowed to load only a modules that are associated
+// with it during link time.
+const Require = iced(function Require(loader, requirer) {
+ let { modules, mapping, resolve } = loader;
+
+ function require(id) {
+ if (!id) // Throw if `id` is not passed.
+ throw Error('you must provide a module name when calling require() from '
+ + requirer.id, requirer.uri);
+
+ // Resolve `id` to its requirer if it's relative.
+ let requirement = requirer ? resolve(id, requirer.id) : id;
+
+
+ // Resolves `uri` of module using loaders resolve function.
+ let uri = resolveURI(requirement, mapping);
+
+ if (!uri) // Throw if `uri` can not be resolved.
+ throw Error('Module: Can not resolve "' + id + '" module required by ' +
+ requirer.id + ' located at ' + requirer.uri, requirer.uri);
+
+ let module = null;
+ // If module is already cached by loader then just use it.
+ if (uri in modules) {
+ module = modules[uri];
+ }
+ // Otherwise load and cache it. We also freeze module to prevent it from
+ // further changes at runtime.
+ else {
+ module = modules[uri] = Module(requirement, uri);
+ freeze(load(loader, module));
+ }
+
+ return module.exports;
+ }
+ // Make `require.main === module` evaluate to true in main module scope.
+ require.main = loader.main === requirer ? requirer : undefined;
+ return iced(require);
+});
+exports.Require = Require;
+
+const main = iced(function main(loader, id) {
+ let uri = resolveURI(id, loader.mapping)
+ let module = loader.main = loader.modules[uri] = Module(id, uri);
+ return load(loader, module).exports;
+});
+exports.main = main;
+
+// Makes module object that is made available to CommonJS modules when they
+// are evaluated, along with `exports` and `require`.
+const Module = iced(function Module(id, uri) {
+ return create(null, {
+ id: { enumerable: true, value: id },
+ exports: { enumerable: true, writable: true, value: create(null) },
+ uri: { value: uri }
+ });
+});
+exports.Module = Module;
+
+// Takes `loader`, and unload `reason` string and notifies all observers that
+// they should cleanup after them-self.
+const unload = iced(function unload(loader, reason) {
+ // subject is a unique object created per loader instance.
+ // This allows any code to cleanup on loader unload regardless of how
+ // it was loaded. To handle unload for specific loader subject may be
+ // asserted against loader.destructor or require('@loader/unload')
+ // Note: We don not destroy loader's module cache or sandboxes map as
+ // some modules may do cleanup in subsequent turns of event loop. Destroying
+ // cache may cause module identity problems in such cases.
+ let subject = { wrappedJSObject: loader.destructor };
+ notifyObservers(subject, 'sdk:loader:destroy', reason);
+});
+exports.unload = unload;
+
+// Function makes new loader that can be used to load CommonJS modules
+// described by a given `options.manifest`. Loader takes following options:
+// - `globals`: Optional map of globals, that all module scopes will inherit
+// from. Map is also exposed under `globals` property of the returned loader
+// so it can be extended further later. Defaults to `{}`.
+// - `modules` Optional map of built-in module exports mapped by module id.
+// These modules will incorporated into module cache. Each module will be
+// frozen.
+// - `resolve` Optional module `id` resolution function. If given it will be
+// used to resolve module URIs, by calling it with require term, requirer
+// module object (that has `uri` property) and `baseURI` of the loader.
+// If `resolve` does not returns `uri` string exception will be thrown by
+// an associated `require` call.
+const Loader = iced(function Loader(options) {
+ let { modules, globals, resolve, paths } = override({
+ paths: {},
+ modules: {},
+ globals: {},
+ resolve: exports.resolve
+ }, options);
+
+ // We create an identity object that will be dispatched on an unload
+ // event as subject. This way unload listeners will be able to assert
+ // which loader is unloaded. Please note that we intentionally don't
+ // use `loader` as subject to prevent a loader access leakage through
+ // observer notifications.
+ let destructor = freeze(create(null));
+
+ // Make mapping array that is sorted from longest path to shortest path
+ // to allow overlays.
+ let mapping = keys(paths).
+ sort(function(a, b) { return b.length - a.length }).
+ map(function(path) { return [ path, paths[path] ] });
+
+ // Define pseudo modules.
+ modules = override({
+ '@loader/unload': destructor,
+ '@loader/options': options,
+ 'chrome': { Cc: Cc, Ci: Ci, Cu: Cu, Cr: Cr, Cm: Cm,
+ CC: bind(CC, Components), components: Components,
+ // `ChromeWorker` has to be inject in loader global scope.
+ // It is done by bootstrap.js:loadSandbox for the SDK.
+ ChromeWorker: ChromeWorker
+ }
+ }, modules);
+
+ modules = keys(modules).reduce(function(result, id) {
+ // We resolve `uri` from `id` since modules are cached by `uri`.
+ let uri = resolveURI(id, mapping);
+ let module = Module(id, uri);
+ module.exports = freeze(modules[id]);
+ result[uri] = freeze(module);
+ return result;
+ }, {});
+
+ // Loader object is just a representation of a environment
+ // state. We freeze it and mark make it's properties non-enumerable
+ // as they are pure implementation detail that no one should rely upon.
+ return freeze(create(null, {
+ destructor: { enumerable: false, value: destructor },
+ globals: { enumerable: false, value: globals },
+ mapping: { enumerable: false, value: mapping },
+ // Map of module objects indexed by module URIs.
+ modules: { enumerable: false, value: modules },
+ // Map of module sandboxes indexed by module URIs.
+ sandboxes: { enumerable: false, value: {} },
+ resolve: { enumerable: false, value: resolve },
+ // Main (entry point) module, it can be set only once, since loader
+ // instance can have only one main module.
+ main: new function() {
+ let main;
+ return {
+ enumerable: false,
+ get: function() { return main; },
+ // Only set main if it has not being set yet!
+ set: function(module) { main = main || module; }
+ }
+ }
+ }));
+});
+exports.Loader = Loader;
+
+});
+