The Tor Browser: comparison toolkit/components/thumbnails/PageThumbsWorker.js

comparison: toolkit/components/thumbnails/PageThumbsWorker.js

toolkit/components/thumbnails/PageThumbsWorker.js

branch: TOR_BUG_3246
changeset 7: 129ffea94266

equal deleted inserted replaced

--1:000000000000
+:272b7ba191a9
+/* 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/. */
+/**
+* A worker dedicated for the I/O component of PageThumbs storage.
+*
+* Do not rely on the API of this worker. In a future version, it might be
+* fully replaced by a OS.File global I/O worker.
+*/
+"use strict";
+importScripts("resource://gre/modules/osfile.jsm");
+let File = OS.File;
+let Type = OS.Shared.Type;
+/**
+* Communications with the controller.
+*
+* Accepts messages:
+* {fun:function_name, args:array_of_arguments_or_null}
+*
+* Sends messages:
+* {ok: result} / {fail: serialized_form_of_OS.File.Error}
+*/
+self.onmessage = function onmessage(msg) {
+let data = msg.data;
+let id = data.id;
+let result;
+if (!(data.fun in Agent)) {
+throw new Error("Cannot find method " + data.fun);
+}
+try {
+result = Agent[data.fun].apply(Agent, data.args);
+} catch (ex if ex instanceof StopIteration) {
+// StopIteration cannot be serialized automatically
+self.postMessage({StopIteration: true, id: id});
+return;
+} catch (ex if ex instanceof OS.File.Error) {
+// Instances of OS.File.Error know how to serialize themselves
+// (deserialization ensures that we end up with OS-specific
+// instances of |OS.File.Error|)
+self.postMessage({fail: OS.File.Error.toMsg(ex), id:id});
+return;
+}
+// Other exceptions do not, and should be propagated through DOM's
+// built-in mechanism for uncaught errors, although this mechanism
+// may lose interesting information.
+self.postMessage({ok: result, id:id});
+};
+let Agent = {
+// Checks if the specified file exists and has an age less than as
+// specifed (in seconds).
+isFileRecent: function Agent_isFileRecent(path, maxAge) {
+try {
+let stat = OS.File.stat(path);
+let maxDate = new Date();
+maxDate.setSeconds(maxDate.getSeconds() - maxAge);
+return stat.lastModificationDate > maxDate;
+} catch (ex if ex instanceof OS.File.Error) {
+// file doesn't exist (or can't be stat'd) - must be stale.
+return false;
+}
+},
+remove: function Agent_removeFile(path) {
+try {
+OS.File.remove(path);
+return true;
+} catch (e) {
+return false;
+}
+},
+expireFilesInDirectory:
+function Agent_expireFilesInDirectory(path, filesToKeep, minChunkSize) {
+let entries = this.getFileEntriesInDirectory(path, filesToKeep);
+let limit = Math.max(minChunkSize, Math.round(entries.length / 2));
+for (let entry of entries) {
+this.remove(entry.path);
+// Check if we reached the limit of files to remove.
+if (--limit <= 0) {
+break;
+}
+}
+return true;
+},
+getFileEntriesInDirectory:
+function Agent_getFileEntriesInDirectory(path, skipFiles) {
+let iter = new OS.File.DirectoryIterator(path);
+if (!iter.exists()) {
+return [];
+}
+let skip = new Set(skipFiles);
+return [entry
+for (entry in iter)
+if (!entry.isDir && !entry.isSymLink && !skip.has(entry.name))];
+},
+moveOrDeleteAllThumbnails:
+function Agent_moveOrDeleteAllThumbnails(pathFrom, pathTo) {
+OS.File.makeDir(pathTo, {ignoreExisting: true});
+if (pathFrom == pathTo) {
+return true;
+}
+let iter = new OS.File.DirectoryIterator(pathFrom);
+if (iter.exists()) {
+for (let entry in iter) {
+if (entry.isDir || entry.isSymLink) {
+continue;
+}
+let from = OS.Path.join(pathFrom, entry.name);
+let to = OS.Path.join(pathTo, entry.name);
+try {
+OS.File.move(from, to, {noOverwrite: true, noCopy: true});
+} catch (e) {
+OS.File.remove(from);
+}
+}
+}
+iter.close();
+try {
+OS.File.removeEmptyDir(pathFrom);
+} catch (e) {
+// This could fail if there's something in
+// the folder we're not permitted to remove.
+}
+return true;
+},
+writeAtomic: function Agent_writeAtomic(path, buffer, options) {
+return File.writeAtomic(path,
+buffer,
+options);
+},
+makeDir: function Agent_makeDir(path, options) {
+return File.makeDir(path, options);
+},
+copy: function Agent_copy(source, dest, options) {
+return File.copy(source, dest, options);
+},
+wipe: function Agent_wipe(path) {
+let iterator = new File.DirectoryIterator(path);
+try {
+for (let entry in iterator) {
+try {
+File.remove(entry.path);
+} catch (ex) {
+// If a file cannot be removed, we should still continue.
+// This can happen at least for any of the following reasons:
+// - access denied;
+// - file has been removed recently during a previous wipe
+//  and the file system has not flushed that yet (yes, this
+//  can happen under Windows);
+// - file has been removed by the user or another process.
+}
+}
+} finally {
+iterator.close();
+}
+},
+exists: function Agent_exists(path) {
+return File.exists(path);
+},
+};