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diff --git a/devtools/shared/DevToolsUtils.js b/devtools/shared/DevToolsUtils.js
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/* General utilities used throughout devtools. */
+
+var { Ci, Cu, Cc, components } = require("chrome");
+var Services = require("Services");
+var promise = require("promise");
+var defer = require("devtools/shared/defer");
+var flags = require("./flags");
+var {getStack, callFunctionWithAsyncStack} = require("devtools/shared/platform/stack");
+
+loader.lazyRequireGetter(this, "FileUtils",
+ "resource://gre/modules/FileUtils.jsm", true);
+
+// Re-export the thread-safe utils.
+const ThreadSafeDevToolsUtils = require("./ThreadSafeDevToolsUtils.js");
+for (let key of Object.keys(ThreadSafeDevToolsUtils)) {
+ exports[key] = ThreadSafeDevToolsUtils[key];
+}
+
+/**
+ * Waits for the next tick in the event loop to execute a callback.
+ */
+exports.executeSoon = function executeSoon(aFn) {
+ if (isWorker) {
+ setImmediate(aFn);
+ } else {
+ let executor;
+ // Only enable async stack reporting when DEBUG_JS_MODULES is set
+ // (customized local builds) to avoid a performance penalty.
+ if (AppConstants.DEBUG_JS_MODULES || flags.testing) {
+ let stack = getStack();
+ executor = () => {
+ callFunctionWithAsyncStack(aFn, stack, "DevToolsUtils.executeSoon");
+ };
+ } else {
+ executor = aFn;
+ }
+ Services.tm.mainThread.dispatch({
+ run: exports.makeInfallible(executor)
+ }, Ci.nsIThread.DISPATCH_NORMAL);
+ }
+};
+
+/**
+ * Waits for the next tick in the event loop.
+ *
+ * @return Promise
+ * A promise that is resolved after the next tick in the event loop.
+ */
+exports.waitForTick = function waitForTick() {
+ let deferred = defer();
+ exports.executeSoon(deferred.resolve);
+ return deferred.promise;
+};
+
+/**
+ * Waits for the specified amount of time to pass.
+ *
+ * @param number aDelay
+ * The amount of time to wait, in milliseconds.
+ * @return Promise
+ * A promise that is resolved after the specified amount of time passes.
+ */
+exports.waitForTime = function waitForTime(aDelay) {
+ let deferred = defer();
+ setTimeout(deferred.resolve, aDelay);
+ return deferred.promise;
+};
+
+/**
+ * Like Array.prototype.forEach, but doesn't cause jankiness when iterating over
+ * very large arrays by yielding to the browser and continuing execution on the
+ * next tick.
+ *
+ * @param Array aArray
+ * The array being iterated over.
+ * @param Function aFn
+ * The function called on each item in the array. If a promise is
+ * returned by this function, iterating over the array will be paused
+ * until the respective promise is resolved.
+ * @returns Promise
+ * A promise that is resolved once the whole array has been iterated
+ * over, and all promises returned by the aFn callback are resolved.
+ */
+exports.yieldingEach = function yieldingEach(aArray, aFn) {
+ const deferred = defer();
+
+ let i = 0;
+ let len = aArray.length;
+ let outstanding = [deferred.promise];
+
+ (function loop() {
+ const start = Date.now();
+
+ while (i < len) {
+ // Don't block the main thread for longer than 16 ms at a time. To
+ // maintain 60fps, you have to render every frame in at least 16ms; we
+ // aren't including time spent in non-JS here, but this is Good
+ // Enough(tm).
+ if (Date.now() - start > 16) {
+ exports.executeSoon(loop);
+ return;
+ }
+
+ try {
+ outstanding.push(aFn(aArray[i], i++));
+ } catch (e) {
+ deferred.reject(e);
+ return;
+ }
+ }
+
+ deferred.resolve();
+ }());
+
+ return promise.all(outstanding);
+};
+
+/**
+ * Like XPCOMUtils.defineLazyGetter, but with a |this| sensitive getter that
+ * allows the lazy getter to be defined on a prototype and work correctly with
+ * instances.
+ *
+ * @param Object aObject
+ * The prototype object to define the lazy getter on.
+ * @param String aKey
+ * The key to define the lazy getter on.
+ * @param Function aCallback
+ * The callback that will be called to determine the value. Will be
+ * called with the |this| value of the current instance.
+ */
+exports.defineLazyPrototypeGetter =
+function defineLazyPrototypeGetter(aObject, aKey, aCallback) {
+ Object.defineProperty(aObject, aKey, {
+ configurable: true,
+ get: function () {
+ const value = aCallback.call(this);
+
+ Object.defineProperty(this, aKey, {
+ configurable: true,
+ writable: true,
+ value: value
+ });
+
+ return value;
+ }
+ });
+};
+
+/**
+ * Safely get the property value from a Debugger.Object for a given key. Walks
+ * the prototype chain until the property is found.
+ *
+ * @param Debugger.Object aObject
+ * The Debugger.Object to get the value from.
+ * @param String aKey
+ * The key to look for.
+ * @return Any
+ */
+exports.getProperty = function getProperty(aObj, aKey) {
+ let root = aObj;
+ try {
+ do {
+ const desc = aObj.getOwnPropertyDescriptor(aKey);
+ if (desc) {
+ if ("value" in desc) {
+ return desc.value;
+ }
+ // Call the getter if it's safe.
+ return exports.hasSafeGetter(desc) ? desc.get.call(root).return : undefined;
+ }
+ aObj = aObj.proto;
+ } while (aObj);
+ } catch (e) {
+ // If anything goes wrong report the error and return undefined.
+ exports.reportException("getProperty", e);
+ }
+ return undefined;
+};
+
+/**
+ * Determines if a descriptor has a getter which doesn't call into JavaScript.
+ *
+ * @param Object aDesc
+ * The descriptor to check for a safe getter.
+ * @return Boolean
+ * Whether a safe getter was found.
+ */
+exports.hasSafeGetter = function hasSafeGetter(aDesc) {
+ // Scripted functions that are CCWs will not appear scripted until after
+ // unwrapping.
+ try {
+ let fn = aDesc.get.unwrap();
+ return fn && fn.callable && fn.class == "Function" && fn.script === undefined;
+ } catch (e) {
+ // Avoid exception 'Object in compartment marked as invisible to Debugger'
+ return false;
+ }
+};
+
+/**
+ * Check if it is safe to read properties and execute methods from the given JS
+ * object. Safety is defined as being protected from unintended code execution
+ * from content scripts (or cross-compartment code).
+ *
+ * See bugs 945920 and 946752 for discussion.
+ *
+ * @type Object aObj
+ * The object to check.
+ * @return Boolean
+ * True if it is safe to read properties from aObj, or false otherwise.
+ */
+exports.isSafeJSObject = function isSafeJSObject(aObj) {
+ // If we are running on a worker thread, Cu is not available. In this case,
+ // we always return false, just to be on the safe side.
+ if (isWorker) {
+ return false;
+ }
+
+ if (Cu.getGlobalForObject(aObj) ==
+ Cu.getGlobalForObject(exports.isSafeJSObject)) {
+ return true; // aObj is not a cross-compartment wrapper.
+ }
+
+ let principal = Cu.getObjectPrincipal(aObj);
+ if (Services.scriptSecurityManager.isSystemPrincipal(principal)) {
+ return true; // allow chrome objects
+ }
+
+ return Cu.isXrayWrapper(aObj);
+};
+
+exports.dumpn = function dumpn(str) {
+ if (flags.wantLogging) {
+ dump("DBG-SERVER: " + str + "\n");
+ }
+};
+
+/**
+ * A verbose logger for low-level tracing.
+ */
+exports.dumpv = function (msg) {
+ if (flags.wantVerbose) {
+ exports.dumpn(msg);
+ }
+};
+
+/**
+ * Defines a getter on a specified object that will be created upon first use.
+ *
+ * @param aObject
+ * The object to define the lazy getter on.
+ * @param aName
+ * The name of the getter to define on aObject.
+ * @param aLambda
+ * A function that returns what the getter should return. This will
+ * only ever be called once.
+ */
+exports.defineLazyGetter = function defineLazyGetter(aObject, aName, aLambda) {
+ Object.defineProperty(aObject, aName, {
+ get: function () {
+ delete aObject[aName];
+ return aObject[aName] = aLambda.apply(aObject);
+ },
+ configurable: true,
+ enumerable: true
+ });
+};
+
+exports.defineLazyGetter(this, "AppConstants", () => {
+ if (isWorker) {
+ return {};
+ }
+ const scope = {};
+ Cu.import("resource://gre/modules/AppConstants.jsm", scope);
+ return scope.AppConstants;
+});
+
+/**
+ * No operation. The empty function.
+ */
+exports.noop = function () { };
+
+let assertionFailureCount = 0;
+
+Object.defineProperty(exports, "assertionFailureCount", {
+ get() {
+ return assertionFailureCount;
+ }
+});
+
+function reallyAssert(condition, message) {
+ if (!condition) {
+ assertionFailureCount++;
+ const err = new Error("Assertion failure: " + message);
+ exports.reportException("DevToolsUtils.assert", err);
+ throw err;
+ }
+}
+
+/**
+ * DevToolsUtils.assert(condition, message)
+ *
+ * @param Boolean condition
+ * @param String message
+ *
+ * Assertions are enabled when any of the following are true:
+ * - This is a DEBUG_JS_MODULES build
+ * - This is a DEBUG build
+ * - flags.testing is set to true
+ *
+ * If assertions are enabled, then `condition` is checked and if false-y, the
+ * assertion failure is logged and then an error is thrown.
+ *
+ * If assertions are not enabled, then this function is a no-op.
+ */
+Object.defineProperty(exports, "assert", {
+ get: () => (AppConstants.DEBUG || AppConstants.DEBUG_JS_MODULES || flags.testing)
+ ? reallyAssert
+ : exports.noop,
+});
+
+/**
+ * Defines a getter on a specified object for a module. The module will not
+ * be imported until first use.
+ *
+ * @param aObject
+ * The object to define the lazy getter on.
+ * @param aName
+ * The name of the getter to define on aObject for the module.
+ * @param aResource
+ * The URL used to obtain the module.
+ * @param aSymbol
+ * The name of the symbol exported by the module.
+ * This parameter is optional and defaults to aName.
+ */
+exports.defineLazyModuleGetter = function defineLazyModuleGetter(aObject, aName,
+ aResource,
+ aSymbol)
+{
+ this.defineLazyGetter(aObject, aName, function XPCU_moduleLambda() {
+ var temp = {};
+ Cu.import(aResource, temp);
+ return temp[aSymbol || aName];
+ });
+};
+
+exports.defineLazyGetter(this, "NetUtil", () => {
+ return Cu.import("resource://gre/modules/NetUtil.jsm", {}).NetUtil;
+});
+
+exports.defineLazyGetter(this, "OS", () => {
+ return Cu.import("resource://gre/modules/osfile.jsm", {}).OS;
+});
+
+exports.defineLazyGetter(this, "TextDecoder", () => {
+ return Cu.import("resource://gre/modules/osfile.jsm", {}).TextDecoder;
+});
+
+exports.defineLazyGetter(this, "NetworkHelper", () => {
+ return require("devtools/shared/webconsole/network-helper");
+});
+
+/**
+ * Performs a request to load the desired URL and returns a promise.
+ *
+ * @param aURL String
+ * The URL we will request.
+ * @param aOptions Object
+ * An object with the following optional properties:
+ * - loadFromCache: if false, will bypass the cache and
+ * always load fresh from the network (default: true)
+ * - policy: the nsIContentPolicy type to apply when fetching the URL
+ * (only works when loading from system principal)
+ * - window: the window to get the loadGroup from
+ * - charset: the charset to use if the channel doesn't provide one
+ * - principal: the principal to use, if omitted, the request is loaded
+ * with a codebase principal corresponding to the url being
+ * loaded, using the origin attributes of the window, if any.
+ * - cacheKey: when loading from cache, use this key to retrieve a cache
+ * specific to a given SHEntry. (Allows loading POST
+ * requests from cache)
+ * @returns Promise that resolves with an object with the following members on
+ * success:
+ * - content: the document at that URL, as a string,
+ * - contentType: the content type of the document
+ *
+ * If an error occurs, the promise is rejected with that error.
+ *
+ * XXX: It may be better to use nsITraceableChannel to get to the sources
+ * without relying on caching when we can (not for eval, etc.):
+ * http://www.softwareishard.com/blog/firebug/nsitraceablechannel-intercept-http-traffic/
+ */
+function mainThreadFetch(aURL, aOptions = { loadFromCache: true,
+ policy: Ci.nsIContentPolicy.TYPE_OTHER,
+ window: null,
+ charset: null,
+ principal: null,
+ cacheKey: null }) {
+ // Create a channel.
+ let url = aURL.split(" -> ").pop();
+ let channel;
+ try {
+ channel = newChannelForURL(url, aOptions);
+ } catch (ex) {
+ return promise.reject(ex);
+ }
+
+ // Set the channel options.
+ channel.loadFlags = aOptions.loadFromCache
+ ? channel.LOAD_FROM_CACHE
+ : channel.LOAD_BYPASS_CACHE;
+
+ // When loading from cache, the cacheKey allows us to target a specific
+ // SHEntry and offer ways to restore POST requests from cache.
+ if (aOptions.loadFromCache &&
+ aOptions.cacheKey && channel instanceof Ci.nsICacheInfoChannel) {
+ channel.cacheKey = aOptions.cacheKey;
+ }
+
+ if (aOptions.window) {
+ // Respect private browsing.
+ channel.loadGroup = aOptions.window.QueryInterface(Ci.nsIInterfaceRequestor)
+ .getInterface(Ci.nsIWebNavigation)
+ .QueryInterface(Ci.nsIDocumentLoader)
+ .loadGroup;
+ }
+
+ let deferred = defer();
+ let onResponse = (stream, status, request) => {
+ if (!components.isSuccessCode(status)) {
+ deferred.reject(new Error(`Failed to fetch ${url}. Code ${status}.`));
+ return;
+ }
+
+ try {
+ // We cannot use NetUtil to do the charset conversion as if charset
+ // information is not available and our default guess is wrong the method
+ // might fail and we lose the stream data. This means we can't fall back
+ // to using the locale default encoding (bug 1181345).
+
+ // Read and decode the data according to the locale default encoding.
+ let available = stream.available();
+ let source = NetUtil.readInputStreamToString(stream, available);
+ stream.close();
+
+ // We do our own BOM sniffing here because there's no convenient
+ // implementation of the "decode" algorithm
+ // (https://encoding.spec.whatwg.org/#decode) exposed to JS.
+ let bomCharset = null;
+ if (available >= 3 && source.codePointAt(0) == 0xef &&
+ source.codePointAt(1) == 0xbb && source.codePointAt(2) == 0xbf) {
+ bomCharset = "UTF-8";
+ source = source.slice(3);
+ } else if (available >= 2 && source.codePointAt(0) == 0xfe &&
+ source.codePointAt(1) == 0xff) {
+ bomCharset = "UTF-16BE";
+ source = source.slice(2);
+ } else if (available >= 2 && source.codePointAt(0) == 0xff &&
+ source.codePointAt(1) == 0xfe) {
+ bomCharset = "UTF-16LE";
+ source = source.slice(2);
+ }
+
+ // If the channel or the caller has correct charset information, the
+ // content will be decoded correctly. If we have to fall back to UTF-8 and
+ // the guess is wrong, the conversion fails and convertToUnicode returns
+ // the input unmodified. Essentially we try to decode the data as UTF-8
+ // and if that fails, we use the locale specific default encoding. This is
+ // the best we can do if the source does not provide charset info.
+ let charset = bomCharset || channel.contentCharset || aOptions.charset || "UTF-8";
+ let unicodeSource = NetworkHelper.convertToUnicode(source, charset);
+
+ deferred.resolve({
+ content: unicodeSource,
+ contentType: request.contentType
+ });
+ } catch (ex) {
+ let uri = request.originalURI;
+ if (ex.name === "NS_BASE_STREAM_CLOSED" && uri instanceof Ci.nsIFileURL) {
+ // Empty files cause NS_BASE_STREAM_CLOSED exception. Use OS.File to
+ // differentiate between empty files and other errors (bug 1170864).
+ // This can be removed when bug 982654 is fixed.
+
+ uri.QueryInterface(Ci.nsIFileURL);
+ let result = OS.File.read(uri.file.path).then(bytes => {
+ // Convert the bytearray to a String.
+ let decoder = new TextDecoder();
+ let content = decoder.decode(bytes);
+
+ // We can't detect the contentType without opening a channel
+ // and that failed already. This is the best we can do here.
+ return {
+ content,
+ contentType: "text/plain"
+ };
+ });
+
+ deferred.resolve(result);
+ } else {
+ deferred.reject(ex);
+ }
+ }
+ };
+
+ // Open the channel
+ try {
+ NetUtil.asyncFetch(channel, onResponse);
+ } catch (ex) {
+ return promise.reject(ex);
+ }
+
+ return deferred.promise;
+}
+
+/**
+ * Opens a channel for given URL. Tries a bit harder than NetUtil.newChannel.
+ *
+ * @param {String} url - The URL to open a channel for.
+ * @param {Object} options - The options object passed to @method fetch.
+ * @return {nsIChannel} - The newly created channel. Throws on failure.
+ */
+function newChannelForURL(url, { policy, window, principal }) {
+ var securityFlags = Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL;
+
+ let uri;
+ try {
+ uri = Services.io.newURI(url, null, null);
+ } catch (e) {
+ // In the xpcshell tests, the script url is the absolute path of the test
+ // file, which will make a malformed URI error be thrown. Add the file
+ // scheme to see if it helps.
+ uri = Services.io.newURI("file://" + url, null, null);
+ }
+ let channelOptions = {
+ contentPolicyType: policy,
+ securityFlags: securityFlags,
+ uri: uri
+ };
+ let prin = principal;
+ if (!prin) {
+ let oa = {};
+ if (window) {
+ oa = window.document.nodePrincipal.originAttributes;
+ }
+ prin = Services.scriptSecurityManager
+ .createCodebasePrincipal(uri, oa);
+ }
+ // contentPolicyType is required when specifying a principal
+ if (!channelOptions.contentPolicyType) {
+ channelOptions.contentPolicyType = Ci.nsIContentPolicy.TYPE_OTHER;
+ }
+ channelOptions.loadingPrincipal = prin;
+
+ try {
+ return NetUtil.newChannel(channelOptions);
+ } catch (e) {
+ // In xpcshell tests on Windows, nsExternalProtocolHandler::NewChannel()
+ // can throw NS_ERROR_UNKNOWN_PROTOCOL if the external protocol isn't
+ // supported by Windows, so we also need to handle the exception here if
+ // parsing the URL above doesn't throw.
+ return newChannelForURL("file://" + url, { policy, window, principal });
+ }
+}
+
+// Fetch is defined differently depending on whether we are on the main thread
+// or a worker thread.
+if (!this.isWorker) {
+ exports.fetch = mainThreadFetch;
+} else {
+ // Services is not available in worker threads, nor is there any other way
+ // to fetch a URL. We need to enlist the help from the main thread here, by
+ // issuing an rpc request, to fetch the URL on our behalf.
+ exports.fetch = function (url, options) {
+ return rpc("fetch", url, options);
+ };
+}
+
+/**
+ * Open the file at the given path for reading.
+ *
+ * @param {String} filePath
+ *
+ * @returns Promise<nsIInputStream>
+ */
+exports.openFileStream = function (filePath) {
+ return new Promise((resolve, reject) => {
+ const uri = NetUtil.newURI(new FileUtils.File(filePath));
+ NetUtil.asyncFetch(
+ { uri, loadUsingSystemPrincipal: true },
+ (stream, result) => {
+ if (!components.isSuccessCode(result)) {
+ reject(new Error(`Could not open "${filePath}": result = ${result}`));
+ return;
+ }
+
+ resolve(stream);
+ }
+ );
+ });
+};
+
+/*
+ * All of the flags have been moved to a different module. Make sure
+ * nobody is accessing them anymore, and don't write new code using
+ * them. We can remove this code after a while.
+ */
+function errorOnFlag(exports, name) {
+ Object.defineProperty(exports, name, {
+ get: () => {
+ const msg = `Cannot get the flag ${name}. ` +
+ `Use the "devtools/shared/flags" module instead`;
+ console.error(msg);
+ throw new Error(msg);
+ },
+ set: () => {
+ const msg = `Cannot set the flag ${name}. ` +
+ `Use the "devtools/shared/flags" module instead`;
+ console.error(msg);
+ throw new Error(msg);
+ }
+ });
+}
+
+errorOnFlag(exports, "testing");
+errorOnFlag(exports, "wantLogging");
+errorOnFlag(exports, "wantVerbose");
+
+// Calls the property with the given `name` on the given `object`, where
+// `name` is a string, and `object` a Debugger.Object instance.
+///
+// This function uses only the Debugger.Object API to call the property. It
+// avoids the use of unsafeDeference. This is useful for example in workers,
+// where unsafeDereference will return an opaque security wrapper to the
+// referent.
+function callPropertyOnObject(object, name) {
+ // Find the property.
+ let descriptor;
+ let proto = object;
+ do {
+ descriptor = proto.getOwnPropertyDescriptor(name);
+ if (descriptor !== undefined) {
+ break;
+ }
+ proto = proto.proto;
+ } while (proto !== null);
+ if (descriptor === undefined) {
+ throw new Error("No such property");
+ }
+ let value = descriptor.value;
+ if (typeof value !== "object" || value === null || !("callable" in value)) {
+ throw new Error("Not a callable object.");
+ }
+
+ // Call the property.
+ let result = value.call(object);
+ if (result === null) {
+ throw new Error("Code was terminated.");
+ }
+ if ("throw" in result) {
+ throw result.throw;
+ }
+ return result.return;
+}
+
+
+exports.callPropertyOnObject = callPropertyOnObject;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 09:43:32 +0000