Merge pull request #5263 from yurydelendik/stream

Implement streaming using moz-chunk-arraybuffer

extensions/chromium/preferences_schema.json

@@ -50,6 +50,12 @@
       "type": "boolean",
       "default": false
     },
+    "disableStream": {
+      "title": "Disable streaming for requests",
+      "description": "Whether to disable streaming for requests (not recommended).",
+      "type": "boolean",
+      "default": false
+    },
     "disableAutoFetch": {
       "type": "boolean",
       "default": false

extensions/firefox/content/PdfStreamConverter.jsm

@@ -178,6 +178,7 @@ function makeContentReadable(obj, window) {
 function PdfDataListener(length) {
   this.length = length; // less than 0, if length is unknown
   this.data = new Uint8Array(length >= 0 ? length : 0x10000);
+  this.position = 0;
   this.loaded = 0;
 }
 
@@ -200,6 +201,11 @@ PdfDataListener.prototype = {
     this.loaded = willBeLoaded;
     this.onprogress(this.loaded, this.length >= 0 ? this.length : void(0));
   },
+  readData: function PdfDataListener_readData() {
+    var data = this.data.subarray(this.position, this.loaded);
+    this.position = this.loaded;
+    return data;
+  },
   getData: function PdfDataListener_getData() {
     var data = this.data;
     if (this.loaded != data.length)
@@ -523,11 +529,13 @@ var RangedChromeActions = (function RangedChromeActionsClosure() {
    */
   function RangedChromeActions(
               domWindow, contentDispositionFilename, originalRequest,
-              dataListener) {
+              rangeEnabled, streamingEnabled, dataListener) {
 
     ChromeActions.call(this, domWindow, contentDispositionFilename);
     this.dataListener = dataListener;
     this.originalRequest = originalRequest;
+    this.rangeEnabled = rangeEnabled;
+    this.streamingEnabled = streamingEnabled;
 
     this.pdfUrl = originalRequest.URI.spec;
     this.contentLength = originalRequest.contentLength;
@@ -585,20 +593,46 @@ var RangedChromeActions = (function RangedChromeActionsClosure() {
   proto.constructor = RangedChromeActions;
 
   proto.initPassiveLoading = function RangedChromeActions_initPassiveLoading() {
-    this.originalRequest.cancel(Cr.NS_BINDING_ABORTED);
+    var self = this;
-    this.originalRequest = null;
+    var data;
+    if (!this.streamingEnabled) {
+      this.originalRequest.cancel(Cr.NS_BINDING_ABORTED);
+      this.originalRequest = null;
+      data = this.dataListener.getData();
+      this.dataListener = null;
+    } else {
+      data = this.dataListener.readData();
+
+      this.dataListener.onprogress = function (loaded, total) {
+        self.domWindow.postMessage({
+          pdfjsLoadAction: 'progressiveRead',
+          loaded: loaded,
+          total: total,
+          chunk: self.dataListener.readData()
+        }, '*');
+      };
+      this.dataListener.oncomplete = function () {
+        delete self.dataListener;
+      };
+    }
+
     this.domWindow.postMessage({
       pdfjsLoadAction: 'supportsRangedLoading',
+      rangeEnabled: this.rangeEnabled,
+      streamingEnabled: this.streamingEnabled,
       pdfUrl: this.pdfUrl,
       length: this.contentLength,
-      data: this.dataListener.getData()
+      data: data
     }, '*');
-    this.dataListener = null;
 
     return true;
   };
 
   proto.requestDataRange = function RangedChromeActions_requestDataRange(args) {
+    if (!this.rangeEnabled) {
+      return;
+    }
+
     var begin = args.begin;
     var end = args.end;
     var domWindow = this.domWindow;
@@ -840,7 +874,8 @@ PdfStreamConverter.prototype = {
     } catch (e) {}
 
     var rangeRequest = false;
-    if (isHttpRequest) {
+    var hash = aRequest.URI.ref;
+    if (isHttpRequest && !getBoolPref(PREF_PREFIX + '.disableRange', false)) {
       var contentEncoding = 'identity';
       try {
         contentEncoding = aRequest.getResponseHeader('Content-Encoding');
@@ -851,12 +886,13 @@ PdfStreamConverter.prototype = {
         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;
+                     hash.toLowerCase().indexOf('disablerange=true') < 0;
     }
+    var streamRequest = !getBoolPref(PREF_PREFIX + '.disableStream', false) &&
+                        hash.toLowerCase().indexOf('disablestream=true') < 0;
 
     aRequest.QueryInterface(Ci.nsIChannel);
 
@@ -914,12 +950,13 @@ PdfStreamConverter.prototype = {
         // may have changed during a redirect.
         var domWindow = getDOMWindow(channel);
         var actions;
-        if (rangeRequest) {
+        if (rangeRequest || streamRequest) {
           actions = new RangedChromeActions(
-              domWindow, contentDispositionFilename, aRequest, dataListener);
+            domWindow, contentDispositionFilename, aRequest,
+            rangeRequest, streamRequest, dataListener);
         } else {
           actions = new StandardChromeActions(
-              domWindow, contentDispositionFilename, dataListener);
+            domWindow, contentDispositionFilename, dataListener);
         }
         var requestListener = new RequestListener(actions);
         domWindow.addEventListener(PDFJS_EVENT_ID, function(event) {

src/core/chunked_stream.js

@@ -30,7 +30,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
     this.numChunksLoaded = 0;
     this.numChunks = Math.ceil(length / chunkSize);
     this.manager = manager;
-    this.initialDataLength = 0;
+    this.progressiveDataLength = 0;
     this.lastSuccessfulEnsureByteChunk = -1;  // a single-entry cache
   }
 
@@ -41,7 +41,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
     getMissingChunks: function ChunkedStream_getMissingChunks() {
       var chunks = [];
       for (var chunk = 0, n = this.numChunks; chunk < n; ++chunk) {
-        if (!(chunk in this.loadedChunks)) {
+        if (!this.loadedChunks[chunk]) {
           chunks.push(chunk);
         }
       }
@@ -73,21 +73,29 @@ var ChunkedStream = (function ChunkedStreamClosure() {
       var curChunk;
 
       for (curChunk = beginChunk; curChunk < endChunk; ++curChunk) {
-        if (!(curChunk in this.loadedChunks)) {
+        if (!this.loadedChunks[curChunk]) {
           this.loadedChunks[curChunk] = true;
           ++this.numChunksLoaded;
         }
       }
     },
 
-    onReceiveInitialData: function ChunkedStream_onReceiveInitialData(data) {
+    onReceiveProgressiveData:
-      this.bytes.set(data);
+        function ChunkedStream_onReceiveProgressiveData(data) {
-      this.initialDataLength = data.length;
+      var position = this.progressiveDataLength;
-      var endChunk = (this.end === data.length ?
+      var beginChunk = Math.floor(position / this.chunkSize);
-        this.numChunks : Math.floor(data.length / this.chunkSize));
+
-      for (var i = 0; i < endChunk; i++) {
+      this.bytes.set(new Uint8Array(data), position);
-        this.loadedChunks[i] = true;
+      position += data.byteLength;
-        ++this.numChunksLoaded;
+      this.progressiveDataLength = position;
+      var endChunk = position >= this.end ? this.numChunks :
+                     Math.floor(position / this.chunkSize);
+      var curChunk;
+      for (curChunk = beginChunk; curChunk < endChunk; ++curChunk) {
+        if (!this.loadedChunks[curChunk]) {
+          this.loadedChunks[curChunk] = true;
+          ++this.numChunksLoaded;
+        }
       }
     },
 
@@ -97,7 +105,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
         return;
       }
 
-      if (!(chunk in this.loadedChunks)) {
+      if (!this.loadedChunks[chunk]) {
         throw new MissingDataException(pos, pos + 1);
       }
       this.lastSuccessfulEnsureByteChunk = chunk;
@@ -108,7 +116,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
         return;
       }
 
-      if (end <= this.initialDataLength) {
+      if (end <= this.progressiveDataLength) {
         return;
       }
 
@@ -116,7 +124,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
       var beginChunk = Math.floor(begin / chunkSize);
       var endChunk = Math.floor((end - 1) / chunkSize) + 1;
       for (var chunk = beginChunk; chunk < endChunk; ++chunk) {
-        if (!(chunk in this.loadedChunks)) {
+        if (!this.loadedChunks[chunk]) {
           throw new MissingDataException(begin, end);
         }
       }
@@ -125,13 +133,13 @@ var ChunkedStream = (function ChunkedStreamClosure() {
     nextEmptyChunk: function ChunkedStream_nextEmptyChunk(beginChunk) {
       var chunk, n;
       for (chunk = beginChunk, n = this.numChunks; chunk < n; ++chunk) {
-        if (!(chunk in this.loadedChunks)) {
+        if (!this.loadedChunks[chunk]) {
           return chunk;
         }
       }
       // Wrap around to beginning
       for (chunk = 0; chunk < beginChunk; ++chunk) {
-        if (!(chunk in this.loadedChunks)) {
+        if (!this.loadedChunks[chunk]) {
           return chunk;
         }
       }
@@ -139,7 +147,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
     },
 
     hasChunk: function ChunkedStream_hasChunk(chunk) {
-      return chunk in this.loadedChunks;
+      return !!this.loadedChunks[chunk];
     },
 
     get length() {
@@ -238,7 +246,7 @@ var ChunkedStream = (function ChunkedStreamClosure() {
         var endChunk = Math.floor((this.end - 1) / chunkSize) + 1;
         var missingChunks = [];
         for (var chunk = beginChunk; chunk < endChunk; ++chunk) {
-          if (!(chunk in this.loadedChunks)) {
+          if (!this.loadedChunks[chunk]) {
             missingChunks.push(chunk);
           }
         }
@@ -300,28 +308,16 @@ var ChunkedStreamManager = (function ChunkedStreamManagerClosure() {
     this.chunksNeededByRequest = {};
     this.requestsByChunk = {};
     this.callbacksByRequest = {};
+    this.progressiveDataLength = 0;
 
     this._loadedStreamCapability = createPromiseCapability();
 
     if (args.initialData) {
-      this.setInitialData(args.initialData);
+      this.onReceiveData({chunk: args.initialData});
     }
   }
 
   ChunkedStreamManager.prototype = {
-
-    setInitialData: function ChunkedStreamManager_setInitialData(data) {
-      this.stream.onReceiveInitialData(data);
-      if (this.stream.allChunksLoaded()) {
-        this._loadedStreamCapability.resolve(this.stream);
-      } else if (this.msgHandler) {
-        this.msgHandler.send('DocProgress', {
-          loaded: data.length,
-          total: this.length
-        });
-      }
-    },
-
     onLoadedStream: function ChunkedStreamManager_getLoadedStream() {
       return this._loadedStreamCapability.promise;
     },
@@ -459,13 +455,21 @@ var ChunkedStreamManager = (function ChunkedStreamManagerClosure() {
 
     onReceiveData: function ChunkedStreamManager_onReceiveData(args) {
       var chunk = args.chunk;
-      var begin = args.begin;
+      var isProgressive = args.begin === undefined;
+      var begin = isProgressive ? this.progressiveDataLength : args.begin;
       var end = begin + chunk.byteLength;
 
-      var beginChunk = this.getBeginChunk(begin);
+      var beginChunk = Math.floor(begin / this.chunkSize);
-      var endChunk = this.getEndChunk(end);
+      var endChunk = end < this.length ? Math.floor(end / this.chunkSize) :
+                                         Math.ceil(end / this.chunkSize);
+
+      if (isProgressive) {
+        this.stream.onReceiveProgressiveData(chunk);
+        this.progressiveDataLength = end;
+      } else {
+        this.stream.onReceiveData(begin, chunk);
+      }
 
-      this.stream.onReceiveData(begin, chunk);
       if (this.stream.allChunksLoaded()) {
         this._loadedStreamCapability.resolve(this.stream);
       }

src/core/network.js

@@ -68,11 +68,11 @@ var NetworkManager = (function NetworkManagerClosure() {
       return data;
     }
     var length = data.length;
-    var buffer = new Uint8Array(length);
+    var array = new Uint8Array(length);
     for (var i = 0; i < length; i++) {
-      buffer[i] = data.charCodeAt(i) & 0xFF;
+      array[i] = data.charCodeAt(i) & 0xFF;
     }
-    return buffer;
+    return array.buffer;
   }
 
   NetworkManager.prototype = {
@@ -87,11 +87,11 @@ var NetworkManager = (function NetworkManagerClosure() {
       return this.request(args);
     },
 
-    requestFull: function NetworkManager_requestRange(listeners) {
+    requestFull: function NetworkManager_requestFull(listeners) {
       return this.request(listeners);
     },
 
-    request: function NetworkManager_requestRange(args) {
+    request: function NetworkManager_request(args) {
       var xhr = this.getXhr();
       var xhrId = this.currXhrId++;
       var pendingRequest = this.pendingRequests[xhrId] = {
@@ -115,27 +115,54 @@ var NetworkManager = (function NetworkManagerClosure() {
         pendingRequest.expectedStatus = 200;
       }
 
-      xhr.responseType = 'arraybuffer';
+      if (args.onProgressiveData) {
-
+        xhr.responseType = 'moz-chunked-arraybuffer';
-      if (args.onProgress) {
+        if (xhr.responseType === 'moz-chunked-arraybuffer') {
-        xhr.onprogress = args.onProgress;
+          pendingRequest.onProgressiveData = args.onProgressiveData;
+          pendingRequest.mozChunked = true;
+        } else {
+          xhr.responseType = 'arraybuffer';
+        }
+      } else {
+        xhr.responseType = 'arraybuffer';
       }
+
       if (args.onError) {
         xhr.onerror = function(evt) {
           args.onError(xhr.status);
         };
       }
       xhr.onreadystatechange = this.onStateChange.bind(this, xhrId);
+      xhr.onprogress = this.onProgress.bind(this, xhrId);
 
       pendingRequest.onHeadersReceived = args.onHeadersReceived;
       pendingRequest.onDone = args.onDone;
       pendingRequest.onError = args.onError;
+      pendingRequest.onProgress = args.onProgress;
 
       xhr.send(null);
 
       return xhrId;
     },
 
+    onProgress: function NetworkManager_onProgress(xhrId, evt) {
+      var pendingRequest = this.pendingRequests[xhrId];
+      if (!pendingRequest) {
+        // Maybe abortRequest was called...
+        return;
+      }
+
+      if (pendingRequest.mozChunked) {
+        var chunk = getArrayBuffer(pendingRequest.xhr);
+        pendingRequest.onProgressiveData(chunk);
+      }
+
+      var onProgress = pendingRequest.onProgress;
+      if (onProgress) {
+        onProgress(evt);
+      }
+    },
+
     onStateChange: function NetworkManager_onStateChange(xhrId, evt) {
       var pendingRequest = this.pendingRequests[xhrId];
       if (!pendingRequest) {
@@ -196,6 +223,8 @@ var NetworkManager = (function NetworkManagerClosure() {
           begin: begin,
           chunk: chunk
         });
+      } else if (pendingRequest.onProgressiveData) {
+        pendingRequest.onDone(null);
       } else {
         pendingRequest.onDone({
           begin: 0,
@@ -215,6 +244,10 @@ var NetworkManager = (function NetworkManagerClosure() {
       return this.pendingRequests[xhrId].xhr;
     },
 
+    isStreamingRequest: function NetworkManager_isStreamingRequest(xhrId) {
+      return !!(this.pendingRequests[xhrId].onProgressiveData);
+    },
+
     isPendingRequest: function NetworkManager_isPendingRequest(xhrId) {
       return xhrId in this.pendingRequests;
     },

src/core/pdf_manager.js

@@ -65,6 +65,10 @@ var BasePdfManager = (function BasePdfManagerClosure() {
       return new NotImplementedException();
     },
 
+    sendProgressiveData: function BasePdfManager_sendProgressiveData(chunk) {
+      return new NotImplementedException();
+    },
+
     updatePassword: function BasePdfManager_updatePassword(password) {
       this.pdfDocument.xref.password = this.password = password;
       if (this._passwordChangedCapability) {
@@ -201,6 +205,11 @@ var NetworkPdfManager = (function NetworkPdfManagerClosure() {
     this.streamManager.requestAllChunks();
   };
 
+  NetworkPdfManager.prototype.sendProgressiveData =
+      function NetworkPdfManager_sendProgressiveData(chunk) {
+    this.streamManager.onReceiveData({ chunk: chunk });
+  };
+
   NetworkPdfManager.prototype.onLoadedStream =
       function NetworkPdfManager_getLoadedStream() {
     return this.streamManager.onLoadedStream();

src/core/worker.js

@@ -16,7 +16,7 @@
  */
 /* globals PDFJS, createPromiseCapability, LocalPdfManager, NetworkPdfManager,
            NetworkManager, isInt, RANGE_CHUNK_SIZE, MissingPDFException,
-           UnexpectedResponseException, PasswordException, Promise,
+           UnexpectedResponseException, PasswordException, Promise, warn,
            PasswordResponses, InvalidPDFException, UnknownErrorException,
            XRefParseException, Ref, info, globalScope, error, MessageHandler */
 
@@ -86,6 +86,7 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
         httpHeaders: source.httpHeaders,
         withCredentials: source.withCredentials
       });
+      var cachedChunks = [];
       var fullRequestXhrId = networkManager.requestFull({
         onHeadersReceived: function onHeadersReceived() {
           if (disableRange) {
@@ -116,11 +117,18 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
             return;
           }
 
-          // NOTE: by cancelling the full request, and then issuing range
+          if (networkManager.isStreamingRequest(fullRequestXhrId)) {
-          // requests, there will be an issue for sites where you can only
+            // We can continue fetching when progressive loading is enabled,
-          // request the pdf once. However, if this is the case, then the
+            // and we don't need the autoFetch feature.
-          // server should not be returning that it can support range requests.
+            source.disableAutoFetch = true;
-          networkManager.abortRequest(fullRequestXhrId);
+          } else {
+            // NOTE: by cancelling the full request, and then issuing range
+            // requests, there will be an issue for sites where you can only
+            // request the pdf once. However, if this is the case, then the
+            // server should not be returning that it can support range
+            // requests.
+            networkManager.abortRequest(fullRequestXhrId);
+          }
 
           try {
             pdfManager = new NetworkPdfManager(source, handler);
@@ -130,10 +138,44 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
           }
         },
 
+        onProgressiveData: PDFJS.disableStream ? null :
+            function onProgressiveData(chunk) {
+          if (!pdfManager) {
+            cachedChunks.push(chunk);
+            return;
+          }
+          pdfManager.sendProgressiveData(chunk);
+        },
+
         onDone: function onDone(args) {
+          if (pdfManager) {
+            return; // already processed
+          }
+
+          var pdfFile;
+          if (args === null) {
+            // TODO add some streaming manager, e.g. for unknown length files.
+            // The data was returned in the onProgressiveData, combining...
+            var pdfFileLength = 0, pos = 0;
+            cachedChunks.forEach(function (chunk) {
+              pdfFileLength += chunk.byteLength;
+            });
+            if (source.length && pdfFileLength !== source.length) {
+              warn('reported HTTP length is different from actual');
+            }
+            var pdfFileArray = new Uint8Array(pdfFileLength);
+            cachedChunks.forEach(function (chunk) {
+              pdfFileArray.set(new Uint8Array(chunk), pos);
+              pos += chunk.byteLength;
+            });
+            pdfFile = pdfFileArray.buffer;
+          } else {
+            pdfFile = args.chunk;
+          }
+
           // the data is array, instantiating directly from it
           try {
-            pdfManager = new LocalPdfManager(args.chunk, source.password);
+            pdfManager = new LocalPdfManager(pdfFile, source.password);
             pdfManagerCapability.resolve();
           } catch (ex) {
             pdfManagerCapability.reject(ex);
@@ -228,6 +270,7 @@ var WorkerMessageHandler = PDFJS.WorkerMessageHandler = {
       PDFJS.cMapPacked = data.cMapPacked === true;
 
       getPdfManager(data).then(function () {
+        handler.send('PDFManagerReady', null);
         pdfManager.onLoadedStream().then(function(stream) {
           handler.send('DataLoaded', { length: stream.bytes.byteLength });
         });

src/display/api.js

@@ -86,6 +86,14 @@ PDFJS.workerSrc = (PDFJS.workerSrc === undefined ? null : PDFJS.workerSrc);
 PDFJS.disableRange = (PDFJS.disableRange === undefined ?
                       false : PDFJS.disableRange);
 
+/**
+ * Disable streaming of PDF file data. By default PDF.js attempts to load PDF
+ * in chunks. This default behavior can be disabled.
+ * @var {boolean}
+ */
+PDFJS.disableStream = (PDFJS.disableStream === undefined ?
+                       false : PDFJS.disableStream);
+
 /**
  * Disable pre-fetching of PDF file data. When range requests are enabled PDF.js
  * will automatically keep fetching more data even if it isn't needed to display
@@ -851,6 +859,12 @@ var WorkerTransport = (function WorkerTransportClosure() {
           });
         });
 
+        pdfDataRangeTransport.addProgressiveReadListener(function(chunk) {
+          messageHandler.send('OnDataRange', {
+            chunk: chunk
+          });
+        });
+
         messageHandler.on('RequestDataRange',
           function transportDataRange(data) {
             pdfDataRangeTransport.requestDataRange(data.begin, data.end);
@@ -911,6 +925,12 @@ var WorkerTransport = (function WorkerTransportClosure() {
         this.downloadInfoCapability.resolve(data);
       }, this);
 
+      messageHandler.on('PDFManagerReady', function transportPage(data) {
+        if (this.pdfDataRangeTransport) {
+          this.pdfDataRangeTransport.transportReady();
+        }
+      }, this);
+
       messageHandler.on('StartRenderPage', function transportRender(data) {
         var page = this.pageCache[data.pageIndex];
 

web/compatibility.js

@@ -167,6 +167,21 @@ if (typeof PDFJS === 'undefined') {
   // The worker will be using XHR, so we can save time and disable worker.
   PDFJS.disableWorker = true;
 
+  Object.defineProperty(xhrPrototype, 'responseType', {
+    get: function xmlHttpRequestGetResponseType() {
+      return this._responseType || 'text';
+    },
+    set: function xmlHttpRequestSetResponseType(value) {
+      if (value === 'text' || value === 'arraybuffer') {
+        this._responseType = value;
+        if (value === 'arraybuffer' &&
+            typeof this.overrideMimeType === 'function') {
+          this.overrideMimeType('text/plain; charset=x-user-defined');
+        }
+      }
+    }
+  });
+
   // Support: IE9
   if (typeof VBArray !== 'undefined') {
     Object.defineProperty(xhrPrototype, 'response', {
@@ -181,25 +196,20 @@ if (typeof PDFJS === 'undefined') {
     return;
   }
 
-  // other browsers
+  Object.defineProperty(xhrPrototype, 'response', {
-  function responseTypeSetter() {
+    get: function xmlHttpRequestResponseGet() {
-    // will be only called to set "arraybuffer"
+      if (this.responseType !== 'arraybuffer') {
-    this.overrideMimeType('text/plain; charset=x-user-defined');
+        return this.responseText;
-  }
+      }
-  if (typeof xhr.overrideMimeType === 'function') {
+      var text = this.responseText;
-    Object.defineProperty(xhrPrototype, 'responseType',
+      var i, n = text.length;
-                          { set: responseTypeSetter });
+      var result = new Uint8Array(n);
-  }
+      for (i = 0; i < n; ++i) {
-  function responseGetter() {
+        result[i] = text.charCodeAt(i) & 0xFF;
-    var text = this.responseText;
+      }
-    var i, n = text.length;
+      return result.buffer;
-    var result = new Uint8Array(n);
-    for (i = 0; i < n; ++i) {
-      result[i] = text.charCodeAt(i) & 0xFF;
     }
-    return result.buffer;
+  });
-  }
-  Object.defineProperty(xhrPrototype, 'response', { get: responseGetter });
 })();
 
 // window.btoa (base64 encode function) ?
@@ -471,6 +481,7 @@ if (typeof PDFJS === 'undefined') {
 
   if (isSafari || isOldAndroid) {
     PDFJS.disableRange = true;
+    PDFJS.disableStream = true;
   }
 })();
 

web/default_preferences.js

@@ -28,6 +28,7 @@ var DEFAULT_PREFERENCES = {
   enableWebGL: false,
   pdfBugEnabled: false,
   disableRange: false,
+  disableStream: false,
   disableAutoFetch: false,
   disableFontFace: false,
 //#if B2G

web/viewer.js

@@ -516,9 +516,15 @@ var PDFView = {
 
 //#if (FIREFOX || MOZCENTRAL)
   initPassiveLoading: function pdfViewInitPassiveLoading() {
+    var pdfDataRangeTransportReadyResolve;
+    var pdfDataRangeTransportReady = new Promise(function (resolve) {
+      pdfDataRangeTransportReadyResolve = resolve;
+    });
     var pdfDataRangeTransport = {
       rangeListeners: [],
       progressListeners: [],
+      progressiveReadListeners: [],
+      ready: pdfDataRangeTransportReady,
 
       addRangeListener: function PdfDataRangeTransport_addRangeListener(
                                    listener) {
@@ -530,6 +536,11 @@ var PDFView = {
         this.progressListeners.push(listener);
       },
 
+      addProgressiveReadListener:
+          function PdfDataRangeTransport_addProgressiveReadListener(listener) {
+        this.progressiveReadListeners.push(listener);
+      },
+
       onDataRange: function PdfDataRangeTransport_onDataRange(begin, chunk) {
         var listeners = this.rangeListeners;
         for (var i = 0, n = listeners.length; i < n; ++i) {
@@ -538,10 +549,26 @@ var PDFView = {
       },
 
       onDataProgress: function PdfDataRangeTransport_onDataProgress(loaded) {
-        var listeners = this.progressListeners;
+        this.ready.then(function () {
-        for (var i = 0, n = listeners.length; i < n; ++i) {
+          var listeners = this.progressListeners;
-          listeners[i](loaded);
+          for (var i = 0, n = listeners.length; i < n; ++i) {
-        }
+            listeners[i](loaded);
+          }
+        }.bind(this));
+      },
+
+      onDataProgressiveRead:
+          function PdfDataRangeTransport_onDataProgress(chunk) {
+        this.ready.then(function () {
+          var listeners = this.progressiveReadListeners;
+          for (var i = 0, n = listeners.length; i < n; ++i) {
+            listeners[i](chunk);
+          }
+        }.bind(this));
+      },
+
+      transportReady: function PdfDataRangeTransport_transportReady() {
+        pdfDataRangeTransportReadyResolve();
       },
 
       requestDataRange: function PdfDataRangeTransport_requestDataRange(
@@ -574,6 +601,9 @@ var PDFView = {
         case 'rangeProgress':
           pdfDataRangeTransport.onDataProgress(args.loaded);
           break;
+        case 'progressiveRead':
+          pdfDataRangeTransport.onDataProgressiveRead(args.chunk);
+          break;
         case 'progress':
           PDFView.progress(args.loaded / args.total);
           break;
@@ -1787,6 +1817,9 @@ function webViewerInitialized() {
     if ('disablerange' in hashParams) {
       PDFJS.disableRange = (hashParams['disablerange'] === 'true');
     }
+    if ('disablestream' in hashParams) {
+      PDFJS.disableStream = (hashParams['disablestream'] === 'true');
+    }
     if ('disableautofetch' in hashParams) {
       PDFJS.disableAutoFetch = (hashParams['disableautofetch'] === 'true');
     }