The Tor Browser: browser/extensions/pdfjs/content/PdfStreamConverter.jsm@6474c204b198 (annotated)

browser/extensions/pdfjs/content/PdfStreamConverter.jsm@6474c204b198 (annotated)

browser/extensions/pdfjs/content/PdfStreamConverter.jsm

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
 /* Copyright 2012 Mozilla Foundation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 /* jshint esnext:true */
 /* globals Components, Services, XPCOMUtils, NetUtil, PrivateBrowsingUtils,
            dump, NetworkManager, PdfJsTelemetry */
 'use strict';
 var EXPORTED_SYMBOLS = ['PdfStreamConverter'];
 const Cc = Components.classes;
 const Ci = Components.interfaces;
 const Cr = Components.results;
 const Cu = Components.utils;
 // True only if this is the version of pdf.js that is included with firefox.
 const MOZ_CENTRAL = JSON.parse('true');
 const PDFJS_EVENT_ID = 'pdf.js.message';
 const PDF_CONTENT_TYPE = 'application/pdf';
 const PREF_PREFIX = 'pdfjs';
 const PDF_VIEWER_WEB_PAGE = 'resource://pdf.js/web/viewer.html';
 const MAX_NUMBER_OF_PREFS = 50;
 const MAX_STRING_PREF_LENGTH = 128;
 Cu.import('resource://gre/modules/XPCOMUtils.jsm');
 Cu.import('resource://gre/modules/Services.jsm');
 Cu.import('resource://gre/modules/NetUtil.jsm');
 XPCOMUtils.defineLazyModuleGetter(this, 'NetworkManager',
   'resource://pdf.js/network.js');
 XPCOMUtils.defineLazyModuleGetter(this, 'PrivateBrowsingUtils',
   'resource://gre/modules/PrivateBrowsingUtils.jsm');
 XPCOMUtils.defineLazyModuleGetter(this, 'PdfJsTelemetry',
   'resource://pdf.js/PdfJsTelemetry.jsm');
 var Svc = {};
 XPCOMUtils.defineLazyServiceGetter(Svc, 'mime',
                                    '@mozilla.org/mime;1',
                                    'nsIMIMEService');
 function getContainingBrowser(domWindow) {
   return domWindow.QueryInterface(Ci.nsIInterfaceRequestor)
                   .getInterface(Ci.nsIWebNavigation)
                   .QueryInterface(Ci.nsIDocShell)
                   .chromeEventHandler;
 }
 function getChromeWindow(domWindow) {
   return getContainingBrowser(domWindow).ownerDocument.defaultView;
 }
 function getFindBar(domWindow) {
   var browser = getContainingBrowser(domWindow);
   try {
     var tabbrowser = browser.getTabBrowser();
     var tab = tabbrowser._getTabForBrowser(browser);
     return tabbrowser.getFindBar(tab);
   } catch (e) {
     // FF22 has no _getTabForBrowser, and FF24 has no getFindBar
     var chromeWindow = browser.ownerDocument.defaultView;
     return chromeWindow.gFindBar;
   }
 }
 function setBoolPref(pref, value) {
   Services.prefs.setBoolPref(pref, value);
 }
 function getBoolPref(pref, def) {
   try {
     return Services.prefs.getBoolPref(pref);
   } catch (ex) {
     return def;
   }
 }
 function setIntPref(pref, value) {
   Services.prefs.setIntPref(pref, value);
 }
 function getIntPref(pref, def) {
   try {
     return Services.prefs.getIntPref(pref);
   } catch (ex) {
     return def;
   }
 }
 function setStringPref(pref, value) {
   var str = Cc['@mozilla.org/supports-string;1']
               .createInstance(Ci.nsISupportsString);
   str.data = value;
   Services.prefs.setComplexValue(pref, Ci.nsISupportsString, str);
 }
 function getStringPref(pref, def) {
   try {
     return Services.prefs.getComplexValue(pref, Ci.nsISupportsString).data;
   } catch (ex) {
     return def;
   }
 }
 function log(aMsg) {
   if (!getBoolPref(PREF_PREFIX + '.pdfBugEnabled', false))
     return;
   var msg = 'PdfStreamConverter.js: ' + (aMsg.join ? aMsg.join('') : aMsg);
   Services.console.logStringMessage(msg);
   dump(msg + '\n');
 }
 function getDOMWindow(aChannel) {
   var requestor = aChannel.notificationCallbacks ?
                   aChannel.notificationCallbacks :
                   aChannel.loadGroup.notificationCallbacks;
   var win = requestor.getInterface(Components.interfaces.nsIDOMWindow);
   return win;
 }
 function getLocalizedStrings(path) {
   var stringBundle = Cc['@mozilla.org/intl/stringbundle;1'].
       getService(Ci.nsIStringBundleService).
       createBundle('chrome://pdf.js/locale/' + path);
   var map = {};
   var enumerator = stringBundle.getSimpleEnumeration();
   while (enumerator.hasMoreElements()) {
     var string = enumerator.getNext().QueryInterface(Ci.nsIPropertyElement);
     var key = string.key, property = 'textContent';
     var i = key.lastIndexOf('.');
     if (i >= 0) {
       property = key.substring(i + 1);
       key = key.substring(0, i);
     }
     if (!(key in map))
       map[key] = {};
     map[key][property] = string.value;
   }
   return map;
 }
 function getLocalizedString(strings, id, property) {
   property = property || 'textContent';
   if (id in strings)
     return strings[id][property];
   return id;
 }
 // PDF data storage
 function PdfDataListener(length) {
   this.length = length; // less than 0, if length is unknown
   this.data = new Uint8Array(length >= 0 ? length : 0x10000);
   this.loaded = 0;
 }
 PdfDataListener.prototype = {
   append: function PdfDataListener_append(chunk) {
     var willBeLoaded = this.loaded + chunk.length;
     if (this.length >= 0 && this.length < willBeLoaded) {
       this.length = -1; // reset the length, server is giving incorrect one
     }
     if (this.length < 0 && this.data.length < willBeLoaded) {
       // data length is unknown and new chunk will not fit in the existing
       // buffer, resizing the buffer by doubling the its last length
       var newLength = this.data.length;
       for (; newLength < willBeLoaded; newLength *= 2) {}
       var newData = new Uint8Array(newLength);
       newData.set(this.data);
       this.data = newData;
     }
     this.data.set(chunk, this.loaded);
     this.loaded = willBeLoaded;
     this.onprogress(this.loaded, this.length >= 0 ? this.length : void(0));
   },
   getData: function PdfDataListener_getData() {
     var data = this.data;
     if (this.loaded != data.length)
       data = data.subarray(0, this.loaded);
     delete this.data; // releasing temporary storage
     return data;
   },
   finish: function PdfDataListener_finish() {
     this.isDataReady = true;
     if (this.oncompleteCallback) {
       this.oncompleteCallback(this.getData());
     }
   },
   error: function PdfDataListener_error(errorCode) {
     this.errorCode = errorCode;
     if (this.oncompleteCallback) {
       this.oncompleteCallback(null, errorCode);
     }
   },
   onprogress: function() {},
   get oncomplete() {
     return this.oncompleteCallback;
   },
   set oncomplete(value) {
     this.oncompleteCallback = value;
     if (this.isDataReady) {
       value(this.getData());
     }
     if (this.errorCode) {
       value(null, this.errorCode);
     }
   }
 };
 // All the priviledged actions.
 function ChromeActions(domWindow, contentDispositionFilename) {
   this.domWindow = domWindow;
   this.contentDispositionFilename = contentDispositionFilename;
   this.telemetryState = {
     documentInfo: false,
     firstPageInfo: false,
     streamTypesUsed: [],
     startAt: Date.now()
   };
 }
 ChromeActions.prototype = {
   isInPrivateBrowsing: function() {
     return PrivateBrowsingUtils.isWindowPrivate(this.domWindow);
   },
   download: function(data, sendResponse) {
     var self = this;
     var originalUrl = data.originalUrl;
     // The data may not be downloaded so we need just retry getting the pdf with
     // the original url.
     var originalUri = NetUtil.newURI(data.originalUrl);
     var filename = data.filename;
     if (typeof filename !== 'string' ||
         (!/\.pdf$/i.test(filename) && !data.isAttachment)) {
       filename = 'document.pdf';
     }
     var blobUri = data.blobUrl ? NetUtil.newURI(data.blobUrl) : originalUri;
     var extHelperAppSvc =
           Cc['@mozilla.org/uriloader/external-helper-app-service;1'].
              getService(Ci.nsIExternalHelperAppService);
     var frontWindow = Cc['@mozilla.org/embedcomp/window-watcher;1'].
                          getService(Ci.nsIWindowWatcher).activeWindow;
     var docIsPrivate = this.isInPrivateBrowsing();
     var netChannel = NetUtil.newChannel(blobUri);
     if ('nsIPrivateBrowsingChannel' in Ci &&
         netChannel instanceof Ci.nsIPrivateBrowsingChannel) {
       netChannel.setPrivate(docIsPrivate);
     }
     NetUtil.asyncFetch(netChannel, function(aInputStream, aResult) {
       if (!Components.isSuccessCode(aResult)) {
         if (sendResponse)
           sendResponse(true);
         return;
       }
       // Create a nsIInputStreamChannel so we can set the url on the channel
       // so the filename will be correct.
       var channel = Cc['@mozilla.org/network/input-stream-channel;1'].
                        createInstance(Ci.nsIInputStreamChannel);
       channel.QueryInterface(Ci.nsIChannel);
       try {
         // contentDisposition/contentDispositionFilename is readonly before FF18
         channel.contentDisposition = Ci.nsIChannel.DISPOSITION_ATTACHMENT;
         if (self.contentDispositionFilename) {
           channel.contentDispositionFilename = self.contentDispositionFilename;
         } else {
           channel.contentDispositionFilename = filename;
         }
       } catch (e) {}
       channel.setURI(originalUri);
       channel.contentStream = aInputStream;
       if ('nsIPrivateBrowsingChannel' in Ci &&
           channel instanceof Ci.nsIPrivateBrowsingChannel) {
         channel.setPrivate(docIsPrivate);
       }
       var listener = {
         extListener: null,
         onStartRequest: function(aRequest, aContext) {
           this.extListener = extHelperAppSvc.doContent((data.isAttachment ? '' :
                                                         'application/pdf'),
                                 aRequest, frontWindow, false);
           this.extListener.onStartRequest(aRequest, aContext);
         },
         onStopRequest: function(aRequest, aContext, aStatusCode) {
           if (this.extListener)
             this.extListener.onStopRequest(aRequest, aContext, aStatusCode);
           // Notify the content code we're done downloading.
           if (sendResponse)
             sendResponse(false);
         },
         onDataAvailable: function(aRequest, aContext, aInputStream, aOffset,
                                   aCount) {
           this.extListener.onDataAvailable(aRequest, aContext, aInputStream,
                                            aOffset, aCount);
         }
       };
       channel.asyncOpen(listener, null);
     });
   },
   getLocale: function() {
     return getStringPref('general.useragent.locale', 'en-US');
   },
   getStrings: function(data) {
     try {
       // Lazy initialization of localizedStrings
       if (!('localizedStrings' in this))
         this.localizedStrings = getLocalizedStrings('viewer.properties');
       var result = this.localizedStrings[data];
       return JSON.stringify(result || null);
     } catch (e) {
       log('Unable to retrive localized strings: ' + e);
       return 'null';
     }
   },
   pdfBugEnabled: function() {
     return getBoolPref(PREF_PREFIX + '.pdfBugEnabled', false);
   },
   supportsIntegratedFind: function() {
     // Integrated find is only supported when we're not in a frame
     if (this.domWindow.frameElement !== null) {
       return false;
     }
     // ... and when the new find events code exists.
     var findBar = getFindBar(this.domWindow);
     return findBar && ('updateControlState' in findBar);
   },
   supportsDocumentFonts: function() {
     var prefBrowser = getIntPref('browser.display.use_document_fonts', 1);
     var prefGfx = getBoolPref('gfx.downloadable_fonts.enabled', true);
     return (!!prefBrowser && prefGfx);
   },
   supportsDocumentColors: function() {
     return getBoolPref('browser.display.use_document_colors', true);
   },
   reportTelemetry: function (data) {
     var probeInfo = JSON.parse(data);
     switch (probeInfo.type) {
       case 'documentInfo':
         if (!this.telemetryState.documentInfo) {
           PdfJsTelemetry.onDocumentVersion(probeInfo.version | 0);
           PdfJsTelemetry.onDocumentGenerator(probeInfo.generator | 0);
           if (probeInfo.formType) {
             PdfJsTelemetry.onForm(probeInfo.formType === 'acroform');
           }
           this.telemetryState.documentInfo = true;
         }
         break;
       case 'pageInfo':
         if (!this.telemetryState.firstPageInfo) {
           var duration = Date.now() - this.telemetryState.startAt;
           PdfJsTelemetry.onTimeToView(duration);
           this.telemetryState.firstPageInfo = true;
         }
         break;
       case 'streamInfo':
         if (!Array.isArray(probeInfo.streamTypes)) {
           break;
         }
         for (var i = 0; i < probeInfo.streamTypes.length; i++) {
           var streamTypeId = probeInfo.streamTypes[i] | 0;
           if (streamTypeId >= 0 && streamTypeId < 10 &&
               !this.telemetryState.streamTypesUsed[streamTypeId]) {
             PdfJsTelemetry.onStreamType(streamTypeId);
             this.telemetryState.streamTypesUsed[streamTypeId] = true;
           }
         }
         break;
     }
   },
   fallback: function(args, sendResponse) {
     var featureId = args.featureId;
     var url = args.url;
     var self = this;
     var domWindow = this.domWindow;
     var strings = getLocalizedStrings('chrome.properties');
     var message;
     if (featureId === 'forms') {
       message = getLocalizedString(strings, 'unsupported_feature_forms');
     } else {
       message = getLocalizedString(strings, 'unsupported_feature');
     }
     PdfJsTelemetry.onFallback();
     var notificationBox = null;
     try {
       // Based on MDN's "Working with windows in chrome code"
       var mainWindow = domWindow
         .QueryInterface(Components.interfaces.nsIInterfaceRequestor)
         .getInterface(Components.interfaces.nsIWebNavigation)
         .QueryInterface(Components.interfaces.nsIDocShellTreeItem)
         .rootTreeItem
         .QueryInterface(Components.interfaces.nsIInterfaceRequestor)
         .getInterface(Components.interfaces.nsIDOMWindow);
       var browser = mainWindow.gBrowser
                               .getBrowserForDocument(domWindow.top.document);
       notificationBox = mainWindow.gBrowser.getNotificationBox(browser);
     } catch (e) {
       log('Unable to get a notification box for the fallback message');
       return;
     }
     // Flag so we don't call the response callback twice, since if the user
     // clicks open with different viewer both the button callback and
     // eventCallback will be called.
     var sentResponse = false;
     var buttons = [{
       label: getLocalizedString(strings, 'open_with_different_viewer'),
       accessKey: getLocalizedString(strings, 'open_with_different_viewer',
                                     'accessKey'),
       callback: function() {
         sentResponse = true;
         sendResponse(true);
       }
     }];
     notificationBox.appendNotification(message, 'pdfjs-fallback', null,
                                        notificationBox.PRIORITY_INFO_LOW,
                                        buttons,
                                        function eventsCallback(eventType) {
       // Currently there is only one event "removed" but if there are any other
       // added in the future we still only care about removed at the moment.
       if (eventType !== 'removed')
         return;
       // Don't send a response again if we already responded when the button was
       // clicked.
       if (!sentResponse)
         sendResponse(false);
     });
   },
   updateFindControlState: function(data) {
     if (!this.supportsIntegratedFind())
       return;
     // Verify what we're sending to the findbar.
     var result = data.result;
     var findPrevious = data.findPrevious;
     var findPreviousType = typeof findPrevious;
     if ((typeof result !== 'number' || result < 0 || result > 3) ||
         (findPreviousType !== 'undefined' && findPreviousType !== 'boolean')) {
       return;
     }
     getFindBar(this.domWindow).updateControlState(result, findPrevious);
   },
   setPreferences: function(prefs, sendResponse) {
     var defaultBranch = Services.prefs.getDefaultBranch(PREF_PREFIX + '.');
     var numberOfPrefs = 0;
     var prefValue, prefName;
     for (var key in prefs) {
       if (++numberOfPrefs > MAX_NUMBER_OF_PREFS) {
         log('setPreferences - Exceeded the maximum number of preferences ' +
             'that is allowed to be set at once.');
         break;
       } else if (!defaultBranch.getPrefType(key)) {
         continue;
       }
       prefValue = prefs[key];
       prefName = (PREF_PREFIX + '.' + key);
       switch (typeof prefValue) {
         case 'boolean':
           setBoolPref(prefName, prefValue);
           break;
         case 'number':
           setIntPref(prefName, prefValue);
           break;
         case 'string':
           if (prefValue.length > MAX_STRING_PREF_LENGTH) {
             log('setPreferences - Exceeded the maximum allowed length ' +
                 'for a string preference.');
           } else {
             setStringPref(prefName, prefValue);
           }
           break;
       }
     }
     if (sendResponse) {
       sendResponse(true);
     }
   },
   getPreferences: function(prefs, sendResponse) {
     var defaultBranch = Services.prefs.getDefaultBranch(PREF_PREFIX + '.');
     var currentPrefs = {}, numberOfPrefs = 0;
     var prefValue, prefName;
     for (var key in prefs) {
       if (++numberOfPrefs > MAX_NUMBER_OF_PREFS) {
         log('getPreferences - Exceeded the maximum number of preferences ' +
             'that is allowed to be fetched at once.');
         break;
       } else if (!defaultBranch.getPrefType(key)) {
         continue;
       }
       prefValue = prefs[key];
       prefName = (PREF_PREFIX + '.' + key);
       switch (typeof prefValue) {
         case 'boolean':
           currentPrefs[key] = getBoolPref(prefName, prefValue);
           break;
         case 'number':
           currentPrefs[key] = getIntPref(prefName, prefValue);
           break;
         case 'string':
           currentPrefs[key] = getStringPref(prefName, prefValue);
           break;
       }
     }
     if (sendResponse) {
       sendResponse(JSON.stringify(currentPrefs));
     } else {
       return JSON.stringify(currentPrefs);
     }
   }
 };
 var RangedChromeActions = (function RangedChromeActionsClosure() {
   /**
    * This is for range requests
    */
   function RangedChromeActions(
               domWindow, contentDispositionFilename, originalRequest,
               dataListener) {
     ChromeActions.call(this, domWindow, contentDispositionFilename);
     this.dataListener = dataListener;
     this.originalRequest = originalRequest;
     this.pdfUrl = originalRequest.URI.spec;
     this.contentLength = originalRequest.contentLength;
     // Pass all the headers from the original request through
     var httpHeaderVisitor = {
       headers: {},
       visitHeader: function(aHeader, aValue) {
         if (aHeader === 'Range') {
           // When loading the PDF from cache, firefox seems to set the Range
           // request header to fetch only the unfetched portions of the file
           // (e.g. 'Range: bytes=1024-'). However, we want to set this header
           // manually to fetch the PDF in chunks.
           return;
         }
         this.headers[aHeader] = aValue;
       }
     };
     originalRequest.visitRequestHeaders(httpHeaderVisitor);
     var self = this;
     var xhr_onreadystatechange = function xhr_onreadystatechange() {
       if (this.readyState === 1) { // LOADING
         var netChannel = this.channel;
         if ('nsIPrivateBrowsingChannel' in Ci &&
             netChannel instanceof Ci.nsIPrivateBrowsingChannel) {
           var docIsPrivate = self.isInPrivateBrowsing();
           netChannel.setPrivate(docIsPrivate);
         }
       }
     };
     var getXhr = function getXhr() {
       const XMLHttpRequest = Components.Constructor(
           '@mozilla.org/xmlextras/xmlhttprequest;1');
       var xhr = new XMLHttpRequest();
       xhr.addEventListener('readystatechange', xhr_onreadystatechange);
       return xhr;
     };
     this.networkManager = new NetworkManager(this.pdfUrl, {
       httpHeaders: httpHeaderVisitor.headers,
       getXhr: getXhr
     });
     // If we are in range request mode, this means we manually issued xhr
     // requests, which we need to abort when we leave the page
     domWindow.addEventListener('unload', function unload(e) {
       self.networkManager.abortAllRequests();
       domWindow.removeEventListener(e.type, unload);
     });
   }
   RangedChromeActions.prototype = Object.create(ChromeActions.prototype);
   var proto = RangedChromeActions.prototype;
   proto.constructor = RangedChromeActions;
   proto.initPassiveLoading = function RangedChromeActions_initPassiveLoading() {
     this.originalRequest.cancel(Cr.NS_BINDING_ABORTED);
     this.originalRequest = null;
     this.domWindow.postMessage({
       pdfjsLoadAction: 'supportsRangedLoading',
       pdfUrl: this.pdfUrl,
       length: this.contentLength,
       data: this.dataListener.getData()
     }, '*');
     this.dataListener = null;
     return true;
   };
   proto.requestDataRange = function RangedChromeActions_requestDataRange(args) {
     var begin = args.begin;
     var end = args.end;
     var domWindow = this.domWindow;
     // TODO(mack): Support error handler. We're not currently not handling
     // errors from chrome code for non-range requests, so this doesn't
     // seem high-pri
     this.networkManager.requestRange(begin, end, {
       onDone: function RangedChromeActions_onDone(args) {
         domWindow.postMessage({
           pdfjsLoadAction: 'range',
           begin: args.begin,
           chunk: args.chunk
         }, '*');
       },
       onProgress: function RangedChromeActions_onProgress(evt) {
         domWindow.postMessage({
           pdfjsLoadAction: 'rangeProgress',
           loaded: evt.loaded,
         }, '*');
       }
     });
   };
   return RangedChromeActions;
 })();
 var StandardChromeActions = (function StandardChromeActionsClosure() {
   /**
    * This is for a single network stream
    */
   function StandardChromeActions(domWindow, contentDispositionFilename,
                                  dataListener) {
     ChromeActions.call(this, domWindow, contentDispositionFilename);
     this.dataListener = dataListener;
   }
   StandardChromeActions.prototype = Object.create(ChromeActions.prototype);
   var proto = StandardChromeActions.prototype;
   proto.constructor = StandardChromeActions;
   proto.initPassiveLoading =
       function StandardChromeActions_initPassiveLoading() {
     if (!this.dataListener) {
       return false;
     }
     var self = this;
     this.dataListener.onprogress = function ChromeActions_dataListenerProgress(
                                       loaded, total) {
       self.domWindow.postMessage({
         pdfjsLoadAction: 'progress',
         loaded: loaded,
         total: total
       }, '*');
     };
     this.dataListener.oncomplete = function ChromeActions_dataListenerComplete(
                                       data, errorCode) {
       self.domWindow.postMessage({
         pdfjsLoadAction: 'complete',
         data: data,
         errorCode: errorCode
       }, '*');
       delete self.dataListener;
     };
     return true;
   };
   return StandardChromeActions;
 })();
 // Event listener to trigger chrome privedged code.
 function RequestListener(actions) {
   this.actions = actions;
 }
 // Receive an event and synchronously or asynchronously responds.
 RequestListener.prototype.receive = function(event) {
   var message = event.target;
   var doc = message.ownerDocument;
   var action = event.detail.action;
   var data = event.detail.data;
   var sync = event.detail.sync;
   var actions = this.actions;
   if (!(action in actions)) {
     log('Unknown action: ' + action);
     return;
   }
   if (sync) {
     var response = actions[action].call(this.actions, data);
     var detail = event.detail;
     detail.__exposedProps__ = {response: 'r'};
     detail.response = response;
   } else {
     var response;
     if (!event.detail.callback) {
       doc.documentElement.removeChild(message);
       response = null;
     } else {
       response = function sendResponse(response) {
         try {
           var listener = doc.createEvent('CustomEvent');
           listener.initCustomEvent('pdf.js.response', true, false,
                                    {response: response,
                                     __exposedProps__: {response: 'r'}});
           return message.dispatchEvent(listener);
         } catch (e) {
           // doc is no longer accessible because the requestor is already
           // gone. unloaded content cannot receive the response anyway.
           return false;
         }
       };
     }
     actions[action].call(this.actions, data, response);
   }
 };
 // Forwards events from the eventElement to the contentWindow only if the
 // content window matches the currently selected browser window.
 function FindEventManager(eventElement, contentWindow, chromeWindow) {
   this.types = ['find',
                 'findagain',
                 'findhighlightallchange',
                 'findcasesensitivitychange'];
   this.chromeWindow = chromeWindow;
   this.contentWindow = contentWindow;
   this.eventElement = eventElement;
 }
 FindEventManager.prototype.bind = function() {
   var unload = function(e) {
     this.unbind();
     this.contentWindow.removeEventListener(e.type, unload);
   }.bind(this);
   this.contentWindow.addEventListener('unload', unload);
   for (var i = 0; i < this.types.length; i++) {
     var type = this.types[i];
     this.eventElement.addEventListener(type, this, true);
   }
 };
 FindEventManager.prototype.handleEvent = function(e) {
   var chromeWindow = this.chromeWindow;
   var contentWindow = this.contentWindow;
   // Only forward the events if they are for our dom window.
   if (chromeWindow.gBrowser.selectedBrowser.contentWindow === contentWindow) {
     var detail = e.detail;
     detail.__exposedProps__ = {
       query: 'r',
       caseSensitive: 'r',
       highlightAll: 'r',
       findPrevious: 'r'
     };
     var forward = contentWindow.document.createEvent('CustomEvent');
     forward.initCustomEvent(e.type, true, true, detail);
     contentWindow.dispatchEvent(forward);
     e.preventDefault();
   }
 };
 FindEventManager.prototype.unbind = function() {
   for (var i = 0; i < this.types.length; i++) {
     var type = this.types[i];
     this.eventElement.removeEventListener(type, this, true);
   }
 };
 function PdfStreamConverter() {
 }
 PdfStreamConverter.prototype = {
   // properties required for XPCOM registration:
   classID: Components.ID('{d0c5195d-e798-49d4-b1d3-9324328b2291}'),
   classDescription: 'pdf.js Component',
   contractID: '@mozilla.org/streamconv;1?from=application/pdf&to=*/*',
   QueryInterface: XPCOMUtils.generateQI([
       Ci.nsISupports,
       Ci.nsIStreamConverter,
       Ci.nsIStreamListener,
       Ci.nsIRequestObserver
   ]),
   /*
    * This component works as such:
    * 1. asyncConvertData stores the listener
    * 2. onStartRequest creates a new channel, streams the viewer
    * 3. If range requests are supported:
    *      3.1. Leave the request open until the viewer is ready to switch to
    *           range requests.
    *
    *    If range rquests are not supported:
    *      3.1. Read the stream as it's loaded in onDataAvailable to send
    *           to the viewer
    *
    * The convert function just returns the stream, it's just the synchronous
    * version of asyncConvertData.
    */
   // nsIStreamConverter::convert
   convert: function(aFromStream, aFromType, aToType, aCtxt) {
     throw Cr.NS_ERROR_NOT_IMPLEMENTED;
   },
   // nsIStreamConverter::asyncConvertData
   asyncConvertData: function(aFromType, aToType, aListener, aCtxt) {
     // Store the listener passed to us
     this.listener = aListener;
   },
   // nsIStreamListener::onDataAvailable
   onDataAvailable: function(aRequest, aContext, aInputStream, aOffset, aCount) {
     if (!this.dataListener) {
       return;
     }
     var binaryStream = this.binaryStream;
     binaryStream.setInputStream(aInputStream);
     var chunk = binaryStream.readByteArray(aCount);
     this.dataListener.append(chunk);
   },
   // nsIRequestObserver::onStartRequest
   onStartRequest: function(aRequest, aContext) {
     // Setup the request so we can use it below.
     var isHttpRequest = false;
     try {
       aRequest.QueryInterface(Ci.nsIHttpChannel);
       isHttpRequest = true;
     } catch (e) {}
     var rangeRequest = false;
     if (isHttpRequest) {
       var contentEncoding = 'identity';
       try {
         contentEncoding = aRequest.getResponseHeader('Content-Encoding');
       } catch (e) {}
       var acceptRanges;
       try {
         acceptRanges = aRequest.getResponseHeader('Accept-Ranges');
       } catch (e) {}
       var hash = aRequest.URI.ref;
       rangeRequest = contentEncoding === 'identity' &&
                      acceptRanges === 'bytes' &&
                      aRequest.contentLength >= 0 &&
                      hash.indexOf('disableRange=true') < 0;
     }
     aRequest.QueryInterface(Ci.nsIChannel);
     aRequest.QueryInterface(Ci.nsIWritablePropertyBag);
     var contentDispositionFilename;
     try {
       contentDispositionFilename = aRequest.contentDispositionFilename;
     } catch (e) {}
     // Change the content type so we don't get stuck in a loop.
     aRequest.setProperty('contentType', aRequest.contentType);
     aRequest.contentType = 'text/html';
     if (isHttpRequest) {
       // We trust PDF viewer, using no CSP
       aRequest.setResponseHeader('Content-Security-Policy', '', false);
       aRequest.setResponseHeader('Content-Security-Policy-Report-Only', '',
                                  false);
       aRequest.setResponseHeader('X-Content-Security-Policy', '', false);
       aRequest.setResponseHeader('X-Content-Security-Policy-Report-Only', '',
                                  false);
     }
     PdfJsTelemetry.onViewerIsUsed();
     PdfJsTelemetry.onDocumentSize(aRequest.contentLength);
     // Creating storage for PDF data
     var contentLength = aRequest.contentLength;
     this.dataListener = new PdfDataListener(contentLength);
     this.binaryStream = Cc['@mozilla.org/binaryinputstream;1']
                         .createInstance(Ci.nsIBinaryInputStream);
     // Create a new channel that is viewer loaded as a resource.
     var ioService = Services.io;
     var channel = ioService.newChannel(
                     PDF_VIEWER_WEB_PAGE, null, null);
     var listener = this.listener;
     var dataListener = this.dataListener;
     // Proxy all the request observer calls, when it gets to onStopRequest
     // we can get the dom window.  We also intentionally pass on the original
     // request(aRequest) below so we don't overwrite the original channel and
     // trigger an assertion.
     var proxy = {
       onStartRequest: function(request, context) {
         listener.onStartRequest(aRequest, context);
       },
       onDataAvailable: function(request, context, inputStream, offset, count) {
         listener.onDataAvailable(aRequest, context, inputStream, offset, count);
       },
       onStopRequest: function(request, context, statusCode) {
         // We get the DOM window here instead of before the request since it
         // may have changed during a redirect.
         var domWindow = getDOMWindow(channel);
         var actions;
         if (rangeRequest) {
           actions = new RangedChromeActions(
               domWindow, contentDispositionFilename, aRequest, dataListener);
         } else {
           actions = new StandardChromeActions(
               domWindow, contentDispositionFilename, dataListener);
         }
         var requestListener = new RequestListener(actions);
         domWindow.addEventListener(PDFJS_EVENT_ID, function(event) {
           requestListener.receive(event);
         }, false, true);
         if (actions.supportsIntegratedFind()) {
           var chromeWindow = getChromeWindow(domWindow);
           var findBar = getFindBar(domWindow);
           var findEventManager = new FindEventManager(findBar,
                                                       domWindow,
                                                       chromeWindow);
           findEventManager.bind();
         }
         listener.onStopRequest(aRequest, context, statusCode);
       }
     };
     // Keep the URL the same so the browser sees it as the same.
     channel.originalURI = aRequest.URI;
     channel.loadGroup = aRequest.loadGroup;
     // We can use resource principal when data is fetched by the chrome
     // e.g. useful for NoScript
     var securityManager = Cc['@mozilla.org/scriptsecuritymanager;1']
                           .getService(Ci.nsIScriptSecurityManager);
     var uri = ioService.newURI(PDF_VIEWER_WEB_PAGE, null, null);
     // FF16 and below had getCodebasePrincipal, it was replaced by
     // getNoAppCodebasePrincipal (bug 758258).
     var resourcePrincipal = 'getNoAppCodebasePrincipal' in securityManager ?
                             securityManager.getNoAppCodebasePrincipal(uri) :
                             securityManager.getCodebasePrincipal(uri);
     aRequest.owner = resourcePrincipal;
     channel.asyncOpen(proxy, aContext);
   },
   // nsIRequestObserver::onStopRequest
   onStopRequest: function(aRequest, aContext, aStatusCode) {
     if (!this.dataListener) {
       // Do nothing
       return;
     }
     if (Components.isSuccessCode(aStatusCode))
       this.dataListener.finish();
     else
       this.dataListener.error(aStatusCode);
     delete this.dataListener;
     delete this.binaryStream;
   }
 };

The Tor Browser / annotate

browser/extensions/pdfjs/content/PdfStreamConverter.jsm@6474c204b198 (annotated)

browser/extensions/pdfjs/content/PdfStreamConverter.jsm