mirror of
https://github.com/zen-browser/pdf.js.git
synced 2025-07-08 17:30:09 +02:00
61ee0de29f
I found that PR 8105 unfortunately causes a *very serious* performance regression in long PDF documents where the `Pages` tree only has one level; my apologies for this! Obviously we cannot revert that PR, since that would cause more issues than it solves. Hence it seems to me that the only viable solution here, is to add a simple `RefSetCache` to reduce the amount of redundant lookups. Previously in PR 8105 caching was thought to be unnecessary, but as it turns out I don't think that we really have a choice in the matter any more.
1803 lines
58 KiB
JavaScript
1803 lines
58 KiB
JavaScript
/* Copyright 2012 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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(function (root, factory) {
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if (typeof define === 'function' && define.amd) {
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define('pdfjs/core/obj', ['exports', 'pdfjs/shared/util',
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'pdfjs/core/primitives', 'pdfjs/core/crypto', 'pdfjs/core/parser',
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'pdfjs/core/chunked_stream', 'pdfjs/core/colorspace'], factory);
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} else if (typeof exports !== 'undefined') {
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factory(exports, require('../shared/util.js'), require('./primitives.js'),
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require('./crypto.js'), require('./parser.js'),
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require('./chunked_stream.js'), require('./colorspace.js'));
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} else {
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factory((root.pdfjsCoreObj = {}), root.pdfjsSharedUtil,
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root.pdfjsCorePrimitives, root.pdfjsCoreCrypto, root.pdfjsCoreParser,
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root.pdfjsCoreChunkedStream, root.pdfjsCoreColorSpace);
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}
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}(this, function (exports, sharedUtil, corePrimitives, coreCrypto, coreParser,
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coreChunkedStream, coreColorSpace) {
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var InvalidPDFException = sharedUtil.InvalidPDFException;
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var MissingDataException = sharedUtil.MissingDataException;
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var XRefParseException = sharedUtil.XRefParseException;
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var assert = sharedUtil.assert;
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var bytesToString = sharedUtil.bytesToString;
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var createPromiseCapability = sharedUtil.createPromiseCapability;
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var error = sharedUtil.error;
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var info = sharedUtil.info;
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var isArray = sharedUtil.isArray;
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var isBool = sharedUtil.isBool;
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var isInt = sharedUtil.isInt;
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var isString = sharedUtil.isString;
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var shadow = sharedUtil.shadow;
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var stringToPDFString = sharedUtil.stringToPDFString;
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var stringToUTF8String = sharedUtil.stringToUTF8String;
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var warn = sharedUtil.warn;
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var createValidAbsoluteUrl = sharedUtil.createValidAbsoluteUrl;
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var Util = sharedUtil.Util;
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var Dict = corePrimitives.Dict;
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var Ref = corePrimitives.Ref;
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var RefSet = corePrimitives.RefSet;
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var RefSetCache = corePrimitives.RefSetCache;
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var isName = corePrimitives.isName;
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var isCmd = corePrimitives.isCmd;
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var isDict = corePrimitives.isDict;
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var isRef = corePrimitives.isRef;
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var isRefsEqual = corePrimitives.isRefsEqual;
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var isStream = corePrimitives.isStream;
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var CipherTransformFactory = coreCrypto.CipherTransformFactory;
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var Lexer = coreParser.Lexer;
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var Parser = coreParser.Parser;
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var ChunkedStream = coreChunkedStream.ChunkedStream;
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var ColorSpace = coreColorSpace.ColorSpace;
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var Catalog = (function CatalogClosure() {
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function Catalog(pdfManager, xref, pageFactory) {
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this.pdfManager = pdfManager;
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this.xref = xref;
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this.catDict = xref.getCatalogObj();
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assert(isDict(this.catDict), 'catalog object is not a dictionary');
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this.fontCache = new RefSetCache();
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this.builtInCMapCache = Object.create(null);
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this.pageKidsCountCache = new RefSetCache();
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// TODO refactor to move getPage() to the PDFDocument.
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this.pageFactory = pageFactory;
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this.pagePromises = [];
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}
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Catalog.prototype = {
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get metadata() {
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var streamRef = this.catDict.getRaw('Metadata');
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if (!isRef(streamRef)) {
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return shadow(this, 'metadata', null);
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}
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var encryptMetadata = (!this.xref.encrypt ? false :
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this.xref.encrypt.encryptMetadata);
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var stream = this.xref.fetch(streamRef, !encryptMetadata);
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var metadata;
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if (stream && isDict(stream.dict)) {
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var type = stream.dict.get('Type');
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var subtype = stream.dict.get('Subtype');
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if (isName(type, 'Metadata') && isName(subtype, 'XML')) {
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// XXX: This should examine the charset the XML document defines,
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// however since there are currently no real means to decode
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// arbitrary charsets, let's just hope that the author of the PDF
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// was reasonable enough to stick with the XML default charset,
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// which is UTF-8.
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try {
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metadata = stringToUTF8String(bytesToString(stream.getBytes()));
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} catch (e) {
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if (e instanceof MissingDataException) {
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throw e;
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}
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info('Skipping invalid metadata.');
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}
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}
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}
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return shadow(this, 'metadata', metadata);
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},
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get toplevelPagesDict() {
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var pagesObj = this.catDict.get('Pages');
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assert(isDict(pagesObj), 'invalid top-level pages dictionary');
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// shadow the prototype getter
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return shadow(this, 'toplevelPagesDict', pagesObj);
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},
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get documentOutline() {
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var obj = null;
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try {
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obj = this.readDocumentOutline();
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} catch (ex) {
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if (ex instanceof MissingDataException) {
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throw ex;
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}
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warn('Unable to read document outline');
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}
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return shadow(this, 'documentOutline', obj);
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},
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readDocumentOutline: function Catalog_readDocumentOutline() {
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var obj = this.catDict.get('Outlines');
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if (!isDict(obj)) {
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return null;
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}
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obj = obj.getRaw('First');
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if (!isRef(obj)) {
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return null;
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}
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var root = { items: [] };
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var queue = [{obj: obj, parent: root}];
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// To avoid recursion, keep track of the already processed items.
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var processed = new RefSet();
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processed.put(obj);
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var xref = this.xref, blackColor = new Uint8Array(3);
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while (queue.length > 0) {
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var i = queue.shift();
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var outlineDict = xref.fetchIfRef(i.obj);
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if (outlineDict === null) {
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continue;
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}
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assert(outlineDict.has('Title'), 'Invalid outline item');
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var data = { url: null, dest: null, };
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Catalog.parseDestDictionary({
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destDict: outlineDict,
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resultObj: data,
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docBaseUrl: this.pdfManager.docBaseUrl,
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});
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var title = outlineDict.get('Title');
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var flags = outlineDict.get('F') || 0;
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var color = outlineDict.getArray('C'), rgbColor = blackColor;
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// We only need to parse the color when it's valid, and non-default.
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if (isArray(color) && color.length === 3 &&
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(color[0] !== 0 || color[1] !== 0 || color[2] !== 0)) {
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rgbColor = ColorSpace.singletons.rgb.getRgb(color, 0);
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}
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var outlineItem = {
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dest: data.dest,
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url: data.url,
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unsafeUrl: data.unsafeUrl,
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newWindow: data.newWindow,
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title: stringToPDFString(title),
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color: rgbColor,
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count: outlineDict.get('Count'),
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bold: !!(flags & 2),
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italic: !!(flags & 1),
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items: []
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};
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i.parent.items.push(outlineItem);
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obj = outlineDict.getRaw('First');
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if (isRef(obj) && !processed.has(obj)) {
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queue.push({obj: obj, parent: outlineItem});
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processed.put(obj);
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}
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obj = outlineDict.getRaw('Next');
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if (isRef(obj) && !processed.has(obj)) {
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queue.push({obj: obj, parent: i.parent});
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processed.put(obj);
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}
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}
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return (root.items.length > 0 ? root.items : null);
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},
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get numPages() {
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var obj = this.toplevelPagesDict.get('Count');
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assert(
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isInt(obj),
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'page count in top level pages object is not an integer'
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);
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// shadow the prototype getter
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return shadow(this, 'num', obj);
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},
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get destinations() {
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function fetchDestination(dest) {
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return isDict(dest) ? dest.get('D') : dest;
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}
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var xref = this.xref;
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var dests = {}, nameTreeRef, nameDictionaryRef;
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var obj = this.catDict.get('Names');
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if (obj && obj.has('Dests')) {
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nameTreeRef = obj.getRaw('Dests');
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} else if (this.catDict.has('Dests')) {
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nameDictionaryRef = this.catDict.get('Dests');
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}
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if (nameDictionaryRef) {
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// reading simple destination dictionary
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obj = nameDictionaryRef;
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obj.forEach(function catalogForEach(key, value) {
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if (!value) {
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return;
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}
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dests[key] = fetchDestination(value);
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});
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}
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if (nameTreeRef) {
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var nameTree = new NameTree(nameTreeRef, xref);
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var names = nameTree.getAll();
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for (var name in names) {
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dests[name] = fetchDestination(names[name]);
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}
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}
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return shadow(this, 'destinations', dests);
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},
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getDestination: function Catalog_getDestination(destinationId) {
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function fetchDestination(dest) {
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return isDict(dest) ? dest.get('D') : dest;
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}
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var xref = this.xref;
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var dest = null, nameTreeRef, nameDictionaryRef;
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var obj = this.catDict.get('Names');
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if (obj && obj.has('Dests')) {
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nameTreeRef = obj.getRaw('Dests');
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} else if (this.catDict.has('Dests')) {
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nameDictionaryRef = this.catDict.get('Dests');
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}
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if (nameDictionaryRef) { // Simple destination dictionary.
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var value = nameDictionaryRef.get(destinationId);
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if (value) {
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dest = fetchDestination(value);
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}
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}
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if (nameTreeRef) {
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var nameTree = new NameTree(nameTreeRef, xref);
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dest = fetchDestination(nameTree.get(destinationId));
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}
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return dest;
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},
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get pageLabels() {
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var obj = null;
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try {
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obj = this.readPageLabels();
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} catch (ex) {
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if (ex instanceof MissingDataException) {
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throw ex;
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}
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warn('Unable to read page labels.');
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}
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return shadow(this, 'pageLabels', obj);
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},
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readPageLabels: function Catalog_readPageLabels() {
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var obj = this.catDict.getRaw('PageLabels');
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if (!obj) {
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return null;
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}
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var pageLabels = new Array(this.numPages);
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var style = null;
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var prefix = '';
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var numberTree = new NumberTree(obj, this.xref);
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var nums = numberTree.getAll();
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var currentLabel = '', currentIndex = 1;
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for (var i = 0, ii = this.numPages; i < ii; i++) {
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if (i in nums) {
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var labelDict = nums[i];
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assert(isDict(labelDict), 'The PageLabel is not a dictionary.');
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var type = labelDict.get('Type');
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assert(!type || isName(type, 'PageLabel'),
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'Invalid type in PageLabel dictionary.');
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var s = labelDict.get('S');
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assert(!s || isName(s), 'Invalid style in PageLabel dictionary.');
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style = s ? s.name : null;
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var p = labelDict.get('P');
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assert(!p || isString(p), 'Invalid prefix in PageLabel dictionary.');
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prefix = p ? stringToPDFString(p) : '';
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var st = labelDict.get('St');
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assert(!st || (isInt(st) && st >= 1),
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'Invalid start in PageLabel dictionary.');
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currentIndex = st || 1;
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}
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switch (style) {
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case 'D':
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currentLabel = currentIndex;
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break;
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case 'R':
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case 'r':
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currentLabel = Util.toRoman(currentIndex, style === 'r');
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break;
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case 'A':
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case 'a':
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var LIMIT = 26; // Use only the characters A--Z, or a--z.
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var A_UPPER_CASE = 0x41, A_LOWER_CASE = 0x61;
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var baseCharCode = (style === 'a' ? A_LOWER_CASE : A_UPPER_CASE);
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var letterIndex = currentIndex - 1;
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var character = String.fromCharCode(baseCharCode +
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(letterIndex % LIMIT));
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var charBuf = [];
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for (var j = 0, jj = (letterIndex / LIMIT) | 0; j <= jj; j++) {
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charBuf.push(character);
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}
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currentLabel = charBuf.join('');
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break;
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default:
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assert(!style,
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'Invalid style "' + style + '" in PageLabel dictionary.');
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}
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pageLabels[i] = prefix + currentLabel;
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currentLabel = '';
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currentIndex++;
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}
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return pageLabels;
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},
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get attachments() {
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var xref = this.xref;
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var attachments = null, nameTreeRef;
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var obj = this.catDict.get('Names');
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if (obj) {
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nameTreeRef = obj.getRaw('EmbeddedFiles');
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}
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if (nameTreeRef) {
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var nameTree = new NameTree(nameTreeRef, xref);
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var names = nameTree.getAll();
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for (var name in names) {
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var fs = new FileSpec(names[name], xref);
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if (!attachments) {
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attachments = Object.create(null);
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}
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attachments[stringToPDFString(name)] = fs.serializable;
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}
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}
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return shadow(this, 'attachments', attachments);
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},
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get javaScript() {
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var xref = this.xref;
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var obj = this.catDict.get('Names');
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var javaScript = [];
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function appendIfJavaScriptDict(jsDict) {
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var type = jsDict.get('S');
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if (!isName(type, 'JavaScript')) {
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return;
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}
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var js = jsDict.get('JS');
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if (isStream(js)) {
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js = bytesToString(js.getBytes());
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} else if (!isString(js)) {
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return;
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}
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javaScript.push(stringToPDFString(js));
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}
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if (obj && obj.has('JavaScript')) {
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var nameTree = new NameTree(obj.getRaw('JavaScript'), xref);
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var names = nameTree.getAll();
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for (var name in names) {
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// We don't really use the JavaScript right now. This code is
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// defensive so we don't cause errors on document load.
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var jsDict = names[name];
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if (isDict(jsDict)) {
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appendIfJavaScriptDict(jsDict);
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}
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}
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}
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// Append OpenAction actions to javaScript array
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var openactionDict = this.catDict.get('OpenAction');
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if (isDict(openactionDict, 'Action')) {
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var actionType = openactionDict.get('S');
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if (isName(actionType, 'Named')) {
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// The named Print action is not a part of the PDF 1.7 specification,
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// but is supported by many PDF readers/writers (including Adobe's).
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var action = openactionDict.get('N');
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if (isName(action, 'Print')) {
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javaScript.push('print({});');
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}
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} else {
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appendIfJavaScriptDict(openactionDict);
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}
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}
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return shadow(this, 'javaScript', javaScript);
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},
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cleanup: function Catalog_cleanup() {
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this.pageKidsCountCache.clear();
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var promises = [];
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this.fontCache.forEach(function (promise) {
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promises.push(promise);
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});
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return Promise.all(promises).then(function (translatedFonts) {
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for (var i = 0, ii = translatedFonts.length; i < ii; i++) {
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var font = translatedFonts[i].dict;
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delete font.translated;
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}
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this.fontCache.clear();
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this.builtInCMapCache = Object.create(null);
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}.bind(this));
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},
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|
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getPage: function Catalog_getPage(pageIndex) {
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if (!(pageIndex in this.pagePromises)) {
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this.pagePromises[pageIndex] = this.getPageDict(pageIndex).then(
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function (a) {
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var dict = a[0];
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var ref = a[1];
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return this.pageFactory.createPage(pageIndex, dict, ref,
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this.fontCache,
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this.builtInCMapCache);
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}.bind(this)
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);
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}
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return this.pagePromises[pageIndex];
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},
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getPageDict: function Catalog_getPageDict(pageIndex) {
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var capability = createPromiseCapability();
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var nodesToVisit = [this.catDict.getRaw('Pages')];
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var count, currentPageIndex = 0;
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var xref = this.xref, pageKidsCountCache = this.pageKidsCountCache;
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|
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function next() {
|
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while (nodesToVisit.length) {
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var currentNode = nodesToVisit.pop();
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|
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if (isRef(currentNode)) {
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count = pageKidsCountCache.get(currentNode);
|
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// Skip nodes where the page can't be.
|
|
if (count > 0 && currentPageIndex + count < pageIndex) {
|
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currentPageIndex += count;
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continue;
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}
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|
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xref.fetchAsync(currentNode).then(function (obj) {
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if (isDict(obj, 'Page') || (isDict(obj) && !obj.has('Kids'))) {
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if (pageIndex === currentPageIndex) {
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// Cache the Page reference, since it can *greatly* improve
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// performance by reducing redundant lookups in long documents
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// where all nodes are found at *one* level of the tree.
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if (currentNode && !pageKidsCountCache.has(currentNode)) {
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pageKidsCountCache.put(currentNode, 1);
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}
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capability.resolve([obj, currentNode]);
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} else {
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currentPageIndex++;
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next();
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}
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return;
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}
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nodesToVisit.push(obj);
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next();
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}, capability.reject);
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return;
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}
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|
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// Must be a child page dictionary.
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assert(isDict(currentNode),
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|
'page dictionary kid reference points to wrong type of object');
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count = currentNode.get('Count');
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// Cache the Kids count, since it can reduce redundant lookups in long
|
|
// documents where all nodes are found at *one* level of the tree.
|
|
var objId = currentNode.objId;
|
|
if (objId && !pageKidsCountCache.has(objId)) {
|
|
pageKidsCountCache.put(objId, count);
|
|
}
|
|
// Skip nodes where the page can't be.
|
|
if (currentPageIndex + count <= pageIndex) {
|
|
currentPageIndex += count;
|
|
continue;
|
|
}
|
|
|
|
var kids = currentNode.get('Kids');
|
|
assert(isArray(kids), 'page dictionary kids object is not an array');
|
|
|
|
// Always check all `Kids` nodes, to avoid getting stuck in an empty
|
|
// node further down in the tree (see issue5644.pdf, issue8088.pdf),
|
|
// and to ensure that we actually find the correct `Page` dict.
|
|
for (var last = kids.length - 1; last >= 0; last--) {
|
|
nodesToVisit.push(kids[last]);
|
|
}
|
|
}
|
|
capability.reject('Page index ' + pageIndex + ' not found.');
|
|
}
|
|
next();
|
|
return capability.promise;
|
|
},
|
|
|
|
getPageIndex: function Catalog_getPageIndex(pageRef) {
|
|
// The page tree nodes have the count of all the leaves below them. To get
|
|
// how many pages are before we just have to walk up the tree and keep
|
|
// adding the count of siblings to the left of the node.
|
|
var xref = this.xref;
|
|
function pagesBeforeRef(kidRef) {
|
|
var total = 0;
|
|
var parentRef;
|
|
return xref.fetchAsync(kidRef).then(function (node) {
|
|
if (isRefsEqual(kidRef, pageRef) && !isDict(node, 'Page') &&
|
|
!(isDict(node) && !node.has('Type') && node.has('Contents'))) {
|
|
throw new Error('The reference does not point to a /Page Dict.');
|
|
}
|
|
if (!node) {
|
|
return null;
|
|
}
|
|
assert(isDict(node), 'node must be a Dict.');
|
|
parentRef = node.getRaw('Parent');
|
|
return node.getAsync('Parent');
|
|
}).then(function (parent) {
|
|
if (!parent) {
|
|
return null;
|
|
}
|
|
assert(isDict(parent), 'parent must be a Dict.');
|
|
return parent.getAsync('Kids');
|
|
}).then(function (kids) {
|
|
if (!kids) {
|
|
return null;
|
|
}
|
|
var kidPromises = [];
|
|
var found = false;
|
|
for (var i = 0; i < kids.length; i++) {
|
|
var kid = kids[i];
|
|
assert(isRef(kid), 'kid must be a Ref.');
|
|
if (kid.num === kidRef.num) {
|
|
found = true;
|
|
break;
|
|
}
|
|
kidPromises.push(xref.fetchAsync(kid).then(function (kid) {
|
|
if (kid.has('Count')) {
|
|
var count = kid.get('Count');
|
|
total += count;
|
|
} else { // page leaf node
|
|
total++;
|
|
}
|
|
}));
|
|
}
|
|
if (!found) {
|
|
error('kid ref not found in parents kids');
|
|
}
|
|
return Promise.all(kidPromises).then(function () {
|
|
return [total, parentRef];
|
|
});
|
|
});
|
|
}
|
|
|
|
var total = 0;
|
|
function next(ref) {
|
|
return pagesBeforeRef(ref).then(function (args) {
|
|
if (!args) {
|
|
return total;
|
|
}
|
|
var count = args[0];
|
|
var parentRef = args[1];
|
|
total += count;
|
|
return next(parentRef);
|
|
});
|
|
}
|
|
|
|
return next(pageRef);
|
|
}
|
|
};
|
|
|
|
/**
|
|
* @typedef ParseDestDictionaryParameters
|
|
* @property {Dict} destDict - The dictionary containing the destination.
|
|
* @property {Object} resultObj - The object where the parsed destination
|
|
* properties will be placed.
|
|
* @property {string} docBaseUrl - (optional) The document base URL that is
|
|
* used when attempting to recover valid absolute URLs from relative ones.
|
|
*/
|
|
|
|
/**
|
|
* Helper function used to parse the contents of destination dictionaries.
|
|
* @param {ParseDestDictionaryParameters} params
|
|
*/
|
|
Catalog.parseDestDictionary = function Catalog_parseDestDictionary(params) {
|
|
// Lets URLs beginning with 'www.' default to using the 'http://' protocol.
|
|
function addDefaultProtocolToUrl(url) {
|
|
if (url.indexOf('www.') === 0) {
|
|
return ('http://' + url);
|
|
}
|
|
return url;
|
|
}
|
|
// According to ISO 32000-1:2008, section 12.6.4.7, URIs should be encoded
|
|
// in 7-bit ASCII. Some bad PDFs use UTF-8 encoding, see Bugzilla 1122280.
|
|
function tryConvertUrlEncoding(url) {
|
|
try {
|
|
return stringToUTF8String(url);
|
|
} catch (e) {
|
|
return url;
|
|
}
|
|
}
|
|
|
|
var destDict = params.destDict;
|
|
if (!isDict(destDict)) {
|
|
warn('Catalog_parseDestDictionary: "destDict" must be a dictionary.');
|
|
return;
|
|
}
|
|
var resultObj = params.resultObj;
|
|
if (typeof resultObj !== 'object') {
|
|
warn('Catalog_parseDestDictionary: "resultObj" must be an object.');
|
|
return;
|
|
}
|
|
var docBaseUrl = params.docBaseUrl || null;
|
|
|
|
var action = destDict.get('A'), url, dest;
|
|
if (isDict(action)) {
|
|
var linkType = action.get('S').name;
|
|
switch (linkType) {
|
|
case 'URI':
|
|
url = action.get('URI');
|
|
if (isName(url)) {
|
|
// Some bad PDFs do not put parentheses around relative URLs.
|
|
url = '/' + url.name;
|
|
} else if (isString(url)) {
|
|
url = addDefaultProtocolToUrl(url);
|
|
}
|
|
// TODO: pdf spec mentions urls can be relative to a Base
|
|
// entry in the dictionary.
|
|
break;
|
|
|
|
case 'GoTo':
|
|
dest = action.get('D');
|
|
break;
|
|
|
|
case 'Launch':
|
|
// We neither want, nor can, support arbitrary 'Launch' actions.
|
|
// However, in practice they are mostly used for linking to other PDF
|
|
// files, which we thus attempt to support (utilizing `docBaseUrl`).
|
|
/* falls through */
|
|
|
|
case 'GoToR':
|
|
var urlDict = action.get('F');
|
|
if (isDict(urlDict)) {
|
|
// We assume that we found a FileSpec dictionary
|
|
// and fetch the URL without checking any further.
|
|
url = urlDict.get('F') || null;
|
|
} else if (isString(urlDict)) {
|
|
url = urlDict;
|
|
}
|
|
|
|
// NOTE: the destination is relative to the *remote* document.
|
|
var remoteDest = action.get('D');
|
|
if (remoteDest) {
|
|
if (isName(remoteDest)) {
|
|
remoteDest = remoteDest.name;
|
|
}
|
|
if (isString(url)) {
|
|
var baseUrl = url.split('#')[0];
|
|
if (isString(remoteDest)) {
|
|
// In practice, a named destination may contain only a number.
|
|
// If that happens, use the '#nameddest=' form to avoid the link
|
|
// redirecting to a page, instead of the correct destination.
|
|
url = baseUrl + '#' +
|
|
(/^\d+$/.test(remoteDest) ? 'nameddest=' : '') + remoteDest;
|
|
} else if (isArray(remoteDest)) {
|
|
url = baseUrl + '#' + JSON.stringify(remoteDest);
|
|
}
|
|
}
|
|
}
|
|
// The 'NewWindow' property, equal to `LinkTarget.BLANK`.
|
|
var newWindow = action.get('NewWindow');
|
|
if (isBool(newWindow)) {
|
|
resultObj.newWindow = newWindow;
|
|
}
|
|
break;
|
|
|
|
case 'Named':
|
|
var namedAction = action.get('N');
|
|
if (isName(namedAction)) {
|
|
resultObj.action = namedAction.name;
|
|
}
|
|
break;
|
|
|
|
case 'JavaScript':
|
|
var jsAction = action.get('JS'), js;
|
|
if (isStream(jsAction)) {
|
|
js = bytesToString(jsAction.getBytes());
|
|
} else if (isString(jsAction)) {
|
|
js = jsAction;
|
|
}
|
|
|
|
if (js) {
|
|
// Attempt to recover valid URLs from 'JS' entries with certain
|
|
// white-listed formats, e.g.
|
|
// - window.open('http://example.com')
|
|
// - app.launchURL('http://example.com', true)
|
|
var URL_OPEN_METHODS = [
|
|
'app.launchURL',
|
|
'window.open'
|
|
];
|
|
var regex = new RegExp(
|
|
'^\\s*(' + URL_OPEN_METHODS.join('|').split('.').join('\\.') +
|
|
')\\((?:\'|\")([^\'\"]*)(?:\'|\")(?:,\\s*(\\w+)\\)|\\))', 'i');
|
|
|
|
var jsUrl = regex.exec(stringToPDFString(js));
|
|
if (jsUrl && jsUrl[2]) {
|
|
url = jsUrl[2];
|
|
|
|
if (jsUrl[3] === 'true' && jsUrl[1] === 'app.launchURL') {
|
|
resultObj.newWindow = true;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
/* falls through */
|
|
default:
|
|
warn('Catalog_parseDestDictionary: Unrecognized link type "' +
|
|
linkType + '".');
|
|
break;
|
|
}
|
|
} else if (destDict.has('Dest')) { // Simple destination link.
|
|
dest = destDict.get('Dest');
|
|
}
|
|
|
|
if (isString(url)) {
|
|
url = tryConvertUrlEncoding(url);
|
|
var absoluteUrl = createValidAbsoluteUrl(url, docBaseUrl);
|
|
if (absoluteUrl) {
|
|
resultObj.url = absoluteUrl.href;
|
|
}
|
|
resultObj.unsafeUrl = url;
|
|
}
|
|
if (dest) {
|
|
if (isName(dest)) {
|
|
dest = dest.name;
|
|
}
|
|
if (isString(dest) || isArray(dest)) {
|
|
resultObj.dest = dest;
|
|
}
|
|
}
|
|
};
|
|
|
|
return Catalog;
|
|
})();
|
|
|
|
var XRef = (function XRefClosure() {
|
|
function XRef(stream, pdfManager) {
|
|
this.stream = stream;
|
|
this.pdfManager = pdfManager;
|
|
this.entries = [];
|
|
this.xrefstms = Object.create(null);
|
|
// prepare the XRef cache
|
|
this.cache = [];
|
|
this.stats = {
|
|
streamTypes: [],
|
|
fontTypes: []
|
|
};
|
|
}
|
|
|
|
XRef.prototype = {
|
|
setStartXRef: function XRef_setStartXRef(startXRef) {
|
|
// Store the starting positions of xref tables as we process them
|
|
// so we can recover from missing data errors
|
|
this.startXRefQueue = [startXRef];
|
|
},
|
|
|
|
parse: function XRef_parse(recoveryMode) {
|
|
var trailerDict;
|
|
if (!recoveryMode) {
|
|
trailerDict = this.readXRef();
|
|
} else {
|
|
warn('Indexing all PDF objects');
|
|
trailerDict = this.indexObjects();
|
|
}
|
|
trailerDict.assignXref(this);
|
|
this.trailer = trailerDict;
|
|
var encrypt = trailerDict.get('Encrypt');
|
|
if (isDict(encrypt)) {
|
|
var ids = trailerDict.get('ID');
|
|
var fileId = (ids && ids.length) ? ids[0] : '';
|
|
// The 'Encrypt' dictionary itself should not be encrypted, and by
|
|
// setting `suppressEncryption` we can prevent an infinite loop inside
|
|
// of `XRef_fetchUncompressed` if the dictionary contains indirect
|
|
// objects (fixes issue7665.pdf).
|
|
encrypt.suppressEncryption = true;
|
|
this.encrypt = new CipherTransformFactory(encrypt, fileId,
|
|
this.pdfManager.password);
|
|
}
|
|
|
|
// get the root dictionary (catalog) object
|
|
if (!(this.root = trailerDict.get('Root'))) {
|
|
error('Invalid root reference');
|
|
}
|
|
},
|
|
|
|
processXRefTable: function XRef_processXRefTable(parser) {
|
|
if (!('tableState' in this)) {
|
|
// Stores state of the table as we process it so we can resume
|
|
// from middle of table in case of missing data error
|
|
this.tableState = {
|
|
entryNum: 0,
|
|
streamPos: parser.lexer.stream.pos,
|
|
parserBuf1: parser.buf1,
|
|
parserBuf2: parser.buf2
|
|
};
|
|
}
|
|
|
|
var obj = this.readXRefTable(parser);
|
|
|
|
// Sanity check
|
|
if (!isCmd(obj, 'trailer')) {
|
|
error('Invalid XRef table: could not find trailer dictionary');
|
|
}
|
|
// Read trailer dictionary, e.g.
|
|
// trailer
|
|
// << /Size 22
|
|
// /Root 20R
|
|
// /Info 10R
|
|
// /ID [ <81b14aafa313db63dbd6f981e49f94f4> ]
|
|
// >>
|
|
// The parser goes through the entire stream << ... >> and provides
|
|
// a getter interface for the key-value table
|
|
var dict = parser.getObj();
|
|
|
|
// The pdflib PDF generator can generate a nested trailer dictionary
|
|
if (!isDict(dict) && dict.dict) {
|
|
dict = dict.dict;
|
|
}
|
|
if (!isDict(dict)) {
|
|
error('Invalid XRef table: could not parse trailer dictionary');
|
|
}
|
|
delete this.tableState;
|
|
|
|
return dict;
|
|
},
|
|
|
|
readXRefTable: function XRef_readXRefTable(parser) {
|
|
// Example of cross-reference table:
|
|
// xref
|
|
// 0 1 <-- subsection header (first obj #, obj count)
|
|
// 0000000000 65535 f <-- actual object (offset, generation #, f/n)
|
|
// 23 2 <-- subsection header ... and so on ...
|
|
// 0000025518 00002 n
|
|
// 0000025635 00000 n
|
|
// trailer
|
|
// ...
|
|
|
|
var stream = parser.lexer.stream;
|
|
var tableState = this.tableState;
|
|
stream.pos = tableState.streamPos;
|
|
parser.buf1 = tableState.parserBuf1;
|
|
parser.buf2 = tableState.parserBuf2;
|
|
|
|
// Outer loop is over subsection headers
|
|
var obj;
|
|
|
|
while (true) {
|
|
if (!('firstEntryNum' in tableState) || !('entryCount' in tableState)) {
|
|
if (isCmd(obj = parser.getObj(), 'trailer')) {
|
|
break;
|
|
}
|
|
tableState.firstEntryNum = obj;
|
|
tableState.entryCount = parser.getObj();
|
|
}
|
|
|
|
var first = tableState.firstEntryNum;
|
|
var count = tableState.entryCount;
|
|
if (!isInt(first) || !isInt(count)) {
|
|
error('Invalid XRef table: wrong types in subsection header');
|
|
}
|
|
// Inner loop is over objects themselves
|
|
for (var i = tableState.entryNum; i < count; i++) {
|
|
tableState.streamPos = stream.pos;
|
|
tableState.entryNum = i;
|
|
tableState.parserBuf1 = parser.buf1;
|
|
tableState.parserBuf2 = parser.buf2;
|
|
|
|
var entry = {};
|
|
entry.offset = parser.getObj();
|
|
entry.gen = parser.getObj();
|
|
var type = parser.getObj();
|
|
|
|
if (isCmd(type, 'f')) {
|
|
entry.free = true;
|
|
} else if (isCmd(type, 'n')) {
|
|
entry.uncompressed = true;
|
|
}
|
|
|
|
// Validate entry obj
|
|
if (!isInt(entry.offset) || !isInt(entry.gen) ||
|
|
!(entry.free || entry.uncompressed)) {
|
|
error('Invalid entry in XRef subsection: ' + first + ', ' + count);
|
|
}
|
|
|
|
// The first xref table entry, i.e. obj 0, should be free. Attempting
|
|
// to adjust an incorrect first obj # (fixes issue 3248 and 7229).
|
|
if (i === 0 && entry.free && first === 1) {
|
|
first = 0;
|
|
}
|
|
|
|
if (!this.entries[i + first]) {
|
|
this.entries[i + first] = entry;
|
|
}
|
|
}
|
|
|
|
tableState.entryNum = 0;
|
|
tableState.streamPos = stream.pos;
|
|
tableState.parserBuf1 = parser.buf1;
|
|
tableState.parserBuf2 = parser.buf2;
|
|
delete tableState.firstEntryNum;
|
|
delete tableState.entryCount;
|
|
}
|
|
|
|
// Sanity check: as per spec, first object must be free
|
|
if (this.entries[0] && !this.entries[0].free) {
|
|
error('Invalid XRef table: unexpected first object');
|
|
}
|
|
return obj;
|
|
},
|
|
|
|
processXRefStream: function XRef_processXRefStream(stream) {
|
|
if (!('streamState' in this)) {
|
|
// Stores state of the stream as we process it so we can resume
|
|
// from middle of stream in case of missing data error
|
|
var streamParameters = stream.dict;
|
|
var byteWidths = streamParameters.get('W');
|
|
var range = streamParameters.get('Index');
|
|
if (!range) {
|
|
range = [0, streamParameters.get('Size')];
|
|
}
|
|
|
|
this.streamState = {
|
|
entryRanges: range,
|
|
byteWidths: byteWidths,
|
|
entryNum: 0,
|
|
streamPos: stream.pos
|
|
};
|
|
}
|
|
this.readXRefStream(stream);
|
|
delete this.streamState;
|
|
|
|
return stream.dict;
|
|
},
|
|
|
|
readXRefStream: function XRef_readXRefStream(stream) {
|
|
var i, j;
|
|
var streamState = this.streamState;
|
|
stream.pos = streamState.streamPos;
|
|
|
|
var byteWidths = streamState.byteWidths;
|
|
var typeFieldWidth = byteWidths[0];
|
|
var offsetFieldWidth = byteWidths[1];
|
|
var generationFieldWidth = byteWidths[2];
|
|
|
|
var entryRanges = streamState.entryRanges;
|
|
while (entryRanges.length > 0) {
|
|
var first = entryRanges[0];
|
|
var n = entryRanges[1];
|
|
|
|
if (!isInt(first) || !isInt(n)) {
|
|
error('Invalid XRef range fields: ' + first + ', ' + n);
|
|
}
|
|
if (!isInt(typeFieldWidth) || !isInt(offsetFieldWidth) ||
|
|
!isInt(generationFieldWidth)) {
|
|
error('Invalid XRef entry fields length: ' + first + ', ' + n);
|
|
}
|
|
for (i = streamState.entryNum; i < n; ++i) {
|
|
streamState.entryNum = i;
|
|
streamState.streamPos = stream.pos;
|
|
|
|
var type = 0, offset = 0, generation = 0;
|
|
for (j = 0; j < typeFieldWidth; ++j) {
|
|
type = (type << 8) | stream.getByte();
|
|
}
|
|
// if type field is absent, its default value is 1
|
|
if (typeFieldWidth === 0) {
|
|
type = 1;
|
|
}
|
|
for (j = 0; j < offsetFieldWidth; ++j) {
|
|
offset = (offset << 8) | stream.getByte();
|
|
}
|
|
for (j = 0; j < generationFieldWidth; ++j) {
|
|
generation = (generation << 8) | stream.getByte();
|
|
}
|
|
var entry = {};
|
|
entry.offset = offset;
|
|
entry.gen = generation;
|
|
switch (type) {
|
|
case 0:
|
|
entry.free = true;
|
|
break;
|
|
case 1:
|
|
entry.uncompressed = true;
|
|
break;
|
|
case 2:
|
|
break;
|
|
default:
|
|
error('Invalid XRef entry type: ' + type);
|
|
}
|
|
if (!this.entries[first + i]) {
|
|
this.entries[first + i] = entry;
|
|
}
|
|
}
|
|
|
|
streamState.entryNum = 0;
|
|
streamState.streamPos = stream.pos;
|
|
entryRanges.splice(0, 2);
|
|
}
|
|
},
|
|
|
|
indexObjects: function XRef_indexObjects() {
|
|
// Simple scan through the PDF content to find objects,
|
|
// trailers and XRef streams.
|
|
var TAB = 0x9, LF = 0xA, CR = 0xD, SPACE = 0x20;
|
|
var PERCENT = 0x25, LT = 0x3C;
|
|
|
|
function readToken(data, offset) {
|
|
var token = '', ch = data[offset];
|
|
while (ch !== LF && ch !== CR && ch !== LT) {
|
|
if (++offset >= data.length) {
|
|
break;
|
|
}
|
|
token += String.fromCharCode(ch);
|
|
ch = data[offset];
|
|
}
|
|
return token;
|
|
}
|
|
function skipUntil(data, offset, what) {
|
|
var length = what.length, dataLength = data.length;
|
|
var skipped = 0;
|
|
// finding byte sequence
|
|
while (offset < dataLength) {
|
|
var i = 0;
|
|
while (i < length && data[offset + i] === what[i]) {
|
|
++i;
|
|
}
|
|
if (i >= length) {
|
|
break; // sequence found
|
|
}
|
|
offset++;
|
|
skipped++;
|
|
}
|
|
return skipped;
|
|
}
|
|
var objRegExp = /^(\d+)\s+(\d+)\s+obj\b/;
|
|
var trailerBytes = new Uint8Array([116, 114, 97, 105, 108, 101, 114]);
|
|
var startxrefBytes = new Uint8Array([115, 116, 97, 114, 116, 120, 114,
|
|
101, 102]);
|
|
var endobjBytes = new Uint8Array([101, 110, 100, 111, 98, 106]);
|
|
var xrefBytes = new Uint8Array([47, 88, 82, 101, 102]);
|
|
|
|
// Clear out any existing entries, since they may be bogus.
|
|
this.entries.length = 0;
|
|
|
|
var stream = this.stream;
|
|
stream.pos = 0;
|
|
var buffer = stream.getBytes();
|
|
var position = stream.start, length = buffer.length;
|
|
var trailers = [], xrefStms = [];
|
|
while (position < length) {
|
|
var ch = buffer[position];
|
|
if (ch === TAB || ch === LF || ch === CR || ch === SPACE) {
|
|
++position;
|
|
continue;
|
|
}
|
|
if (ch === PERCENT) { // %-comment
|
|
do {
|
|
++position;
|
|
if (position >= length) {
|
|
break;
|
|
}
|
|
ch = buffer[position];
|
|
} while (ch !== LF && ch !== CR);
|
|
continue;
|
|
}
|
|
var token = readToken(buffer, position);
|
|
var m;
|
|
if (token.indexOf('xref') === 0 &&
|
|
(token.length === 4 || /\s/.test(token[4]))) {
|
|
position += skipUntil(buffer, position, trailerBytes);
|
|
trailers.push(position);
|
|
position += skipUntil(buffer, position, startxrefBytes);
|
|
} else if ((m = objRegExp.exec(token))) {
|
|
if (typeof this.entries[m[1]] === 'undefined') {
|
|
this.entries[m[1]] = {
|
|
offset: position - stream.start,
|
|
gen: m[2] | 0,
|
|
uncompressed: true
|
|
};
|
|
}
|
|
var contentLength = skipUntil(buffer, position, endobjBytes) + 7;
|
|
var content = buffer.subarray(position, position + contentLength);
|
|
|
|
// checking XRef stream suspect
|
|
// (it shall have '/XRef' and next char is not a letter)
|
|
var xrefTagOffset = skipUntil(content, 0, xrefBytes);
|
|
if (xrefTagOffset < contentLength &&
|
|
content[xrefTagOffset + 5] < 64) {
|
|
xrefStms.push(position - stream.start);
|
|
this.xrefstms[position - stream.start] = 1; // Avoid recursion
|
|
}
|
|
|
|
position += contentLength;
|
|
} else if (token.indexOf('trailer') === 0 &&
|
|
(token.length === 7 || /\s/.test(token[7]))) {
|
|
trailers.push(position);
|
|
position += skipUntil(buffer, position, startxrefBytes);
|
|
} else {
|
|
position += token.length + 1;
|
|
}
|
|
}
|
|
// reading XRef streams
|
|
var i, ii;
|
|
for (i = 0, ii = xrefStms.length; i < ii; ++i) {
|
|
this.startXRefQueue.push(xrefStms[i]);
|
|
this.readXRef(/* recoveryMode */ true);
|
|
}
|
|
// finding main trailer
|
|
var dict;
|
|
for (i = 0, ii = trailers.length; i < ii; ++i) {
|
|
stream.pos = trailers[i];
|
|
var parser = new Parser(new Lexer(stream), /* allowStreams = */ true,
|
|
/* xref = */ this, /* recoveryMode = */ true);
|
|
var obj = parser.getObj();
|
|
if (!isCmd(obj, 'trailer')) {
|
|
continue;
|
|
}
|
|
// read the trailer dictionary
|
|
dict = parser.getObj();
|
|
if (!isDict(dict)) {
|
|
continue;
|
|
}
|
|
// taking the first one with 'ID'
|
|
if (dict.has('ID')) {
|
|
return dict;
|
|
}
|
|
}
|
|
// no tailer with 'ID', taking last one (if exists)
|
|
if (dict) {
|
|
return dict;
|
|
}
|
|
// nothing helps
|
|
// calling error() would reject worker with an UnknownErrorException.
|
|
throw new InvalidPDFException('Invalid PDF structure');
|
|
},
|
|
|
|
readXRef: function XRef_readXRef(recoveryMode) {
|
|
var stream = this.stream;
|
|
|
|
try {
|
|
while (this.startXRefQueue.length) {
|
|
var startXRef = this.startXRefQueue[0];
|
|
|
|
stream.pos = startXRef + stream.start;
|
|
|
|
var parser = new Parser(new Lexer(stream), true, this);
|
|
var obj = parser.getObj();
|
|
var dict;
|
|
|
|
// Get dictionary
|
|
if (isCmd(obj, 'xref')) {
|
|
// Parse end-of-file XRef
|
|
dict = this.processXRefTable(parser);
|
|
if (!this.topDict) {
|
|
this.topDict = dict;
|
|
}
|
|
|
|
// Recursively get other XRefs 'XRefStm', if any
|
|
obj = dict.get('XRefStm');
|
|
if (isInt(obj)) {
|
|
var pos = obj;
|
|
// ignore previously loaded xref streams
|
|
// (possible infinite recursion)
|
|
if (!(pos in this.xrefstms)) {
|
|
this.xrefstms[pos] = 1;
|
|
this.startXRefQueue.push(pos);
|
|
}
|
|
}
|
|
} else if (isInt(obj)) {
|
|
// Parse in-stream XRef
|
|
if (!isInt(parser.getObj()) ||
|
|
!isCmd(parser.getObj(), 'obj') ||
|
|
!isStream(obj = parser.getObj())) {
|
|
error('Invalid XRef stream');
|
|
}
|
|
dict = this.processXRefStream(obj);
|
|
if (!this.topDict) {
|
|
this.topDict = dict;
|
|
}
|
|
if (!dict) {
|
|
error('Failed to read XRef stream');
|
|
}
|
|
} else {
|
|
error('Invalid XRef stream header');
|
|
}
|
|
|
|
// Recursively get previous dictionary, if any
|
|
obj = dict.get('Prev');
|
|
if (isInt(obj)) {
|
|
this.startXRefQueue.push(obj);
|
|
} else if (isRef(obj)) {
|
|
// The spec says Prev must not be a reference, i.e. "/Prev NNN"
|
|
// This is a fallback for non-compliant PDFs, i.e. "/Prev NNN 0 R"
|
|
this.startXRefQueue.push(obj.num);
|
|
}
|
|
|
|
this.startXRefQueue.shift();
|
|
}
|
|
|
|
return this.topDict;
|
|
} catch (e) {
|
|
if (e instanceof MissingDataException) {
|
|
throw e;
|
|
}
|
|
info('(while reading XRef): ' + e);
|
|
}
|
|
|
|
if (recoveryMode) {
|
|
return;
|
|
}
|
|
throw new XRefParseException();
|
|
},
|
|
|
|
getEntry: function XRef_getEntry(i) {
|
|
var xrefEntry = this.entries[i];
|
|
if (xrefEntry && !xrefEntry.free && xrefEntry.offset) {
|
|
return xrefEntry;
|
|
}
|
|
return null;
|
|
},
|
|
|
|
fetchIfRef: function XRef_fetchIfRef(obj, suppressEncryption) {
|
|
if (!isRef(obj)) {
|
|
return obj;
|
|
}
|
|
return this.fetch(obj, suppressEncryption);
|
|
},
|
|
|
|
fetch: function XRef_fetch(ref, suppressEncryption) {
|
|
assert(isRef(ref), 'ref object is not a reference');
|
|
var num = ref.num;
|
|
if (num in this.cache) {
|
|
var cacheEntry = this.cache[num];
|
|
// In documents with Object Streams, it's possible that cached `Dict`s
|
|
// have not been assigned an `objId` yet (see e.g. issue3115r.pdf).
|
|
if (cacheEntry instanceof Dict && !cacheEntry.objId) {
|
|
cacheEntry.objId = ref.toString();
|
|
}
|
|
return cacheEntry;
|
|
}
|
|
|
|
var xrefEntry = this.getEntry(num);
|
|
|
|
// the referenced entry can be free
|
|
if (xrefEntry === null) {
|
|
return (this.cache[num] = null);
|
|
}
|
|
|
|
if (xrefEntry.uncompressed) {
|
|
xrefEntry = this.fetchUncompressed(ref, xrefEntry, suppressEncryption);
|
|
} else {
|
|
xrefEntry = this.fetchCompressed(xrefEntry, suppressEncryption);
|
|
}
|
|
if (isDict(xrefEntry)) {
|
|
xrefEntry.objId = ref.toString();
|
|
} else if (isStream(xrefEntry)) {
|
|
xrefEntry.dict.objId = ref.toString();
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
fetchUncompressed: function XRef_fetchUncompressed(ref, xrefEntry,
|
|
suppressEncryption) {
|
|
var gen = ref.gen;
|
|
var num = ref.num;
|
|
if (xrefEntry.gen !== gen) {
|
|
error('inconsistent generation in XRef');
|
|
}
|
|
var stream = this.stream.makeSubStream(xrefEntry.offset +
|
|
this.stream.start);
|
|
var parser = new Parser(new Lexer(stream), true, this);
|
|
var obj1 = parser.getObj();
|
|
var obj2 = parser.getObj();
|
|
var obj3 = parser.getObj();
|
|
if (!isInt(obj1) || parseInt(obj1, 10) !== num ||
|
|
!isInt(obj2) || parseInt(obj2, 10) !== gen ||
|
|
!isCmd(obj3)) {
|
|
error('bad XRef entry');
|
|
}
|
|
if (!isCmd(obj3, 'obj')) {
|
|
// some bad PDFs use "obj1234" and really mean 1234
|
|
if (obj3.cmd.indexOf('obj') === 0) {
|
|
num = parseInt(obj3.cmd.substring(3), 10);
|
|
if (!isNaN(num)) {
|
|
return num;
|
|
}
|
|
}
|
|
error('bad XRef entry');
|
|
}
|
|
if (this.encrypt && !suppressEncryption) {
|
|
xrefEntry = parser.getObj(this.encrypt.createCipherTransform(num, gen));
|
|
} else {
|
|
xrefEntry = parser.getObj();
|
|
}
|
|
if (!isStream(xrefEntry)) {
|
|
this.cache[num] = xrefEntry;
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
fetchCompressed: function XRef_fetchCompressed(xrefEntry,
|
|
suppressEncryption) {
|
|
var tableOffset = xrefEntry.offset;
|
|
var stream = this.fetch(new Ref(tableOffset, 0));
|
|
if (!isStream(stream)) {
|
|
error('bad ObjStm stream');
|
|
}
|
|
var first = stream.dict.get('First');
|
|
var n = stream.dict.get('N');
|
|
if (!isInt(first) || !isInt(n)) {
|
|
error('invalid first and n parameters for ObjStm stream');
|
|
}
|
|
var parser = new Parser(new Lexer(stream), false, this);
|
|
parser.allowStreams = true;
|
|
var i, entries = [], num, nums = [];
|
|
// read the object numbers to populate cache
|
|
for (i = 0; i < n; ++i) {
|
|
num = parser.getObj();
|
|
if (!isInt(num)) {
|
|
error('invalid object number in the ObjStm stream: ' + num);
|
|
}
|
|
nums.push(num);
|
|
var offset = parser.getObj();
|
|
if (!isInt(offset)) {
|
|
error('invalid object offset in the ObjStm stream: ' + offset);
|
|
}
|
|
}
|
|
// read stream objects for cache
|
|
for (i = 0; i < n; ++i) {
|
|
entries.push(parser.getObj());
|
|
// The ObjStm should not contain 'endobj'. If it's present, skip over it
|
|
// to support corrupt PDFs (fixes issue 5241, bug 898610, bug 1037816).
|
|
if (isCmd(parser.buf1, 'endobj')) {
|
|
parser.shift();
|
|
}
|
|
num = nums[i];
|
|
var entry = this.entries[num];
|
|
if (entry && entry.offset === tableOffset && entry.gen === i) {
|
|
this.cache[num] = entries[i];
|
|
}
|
|
}
|
|
xrefEntry = entries[xrefEntry.gen];
|
|
if (xrefEntry === undefined) {
|
|
error('bad XRef entry for compressed object');
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
fetchIfRefAsync: function XRef_fetchIfRefAsync(obj, suppressEncryption) {
|
|
if (!isRef(obj)) {
|
|
return Promise.resolve(obj);
|
|
}
|
|
return this.fetchAsync(obj, suppressEncryption);
|
|
},
|
|
|
|
fetchAsync: function XRef_fetchAsync(ref, suppressEncryption) {
|
|
var streamManager = this.stream.manager;
|
|
var xref = this;
|
|
return new Promise(function tryFetch(resolve, reject) {
|
|
try {
|
|
resolve(xref.fetch(ref, suppressEncryption));
|
|
} catch (e) {
|
|
if (e instanceof MissingDataException) {
|
|
streamManager.requestRange(e.begin, e.end).then(function () {
|
|
tryFetch(resolve, reject);
|
|
}, reject);
|
|
return;
|
|
}
|
|
reject(e);
|
|
}
|
|
});
|
|
},
|
|
|
|
getCatalogObj: function XRef_getCatalogObj() {
|
|
return this.root;
|
|
}
|
|
};
|
|
|
|
return XRef;
|
|
})();
|
|
|
|
/**
|
|
* A NameTree/NumberTree is like a Dict but has some advantageous properties,
|
|
* see the specification (7.9.6 and 7.9.7) for additional details.
|
|
* TODO: implement all the Dict functions and make this more efficient.
|
|
*/
|
|
var NameOrNumberTree = (function NameOrNumberTreeClosure() {
|
|
function NameOrNumberTree(root, xref) {
|
|
throw new Error('Cannot initialize NameOrNumberTree.');
|
|
}
|
|
|
|
NameOrNumberTree.prototype = {
|
|
getAll: function NameOrNumberTree_getAll() {
|
|
var dict = Object.create(null);
|
|
if (!this.root) {
|
|
return dict;
|
|
}
|
|
var xref = this.xref;
|
|
// Reading Name/Number tree.
|
|
var processed = new RefSet();
|
|
processed.put(this.root);
|
|
var queue = [this.root];
|
|
while (queue.length > 0) {
|
|
var i, n;
|
|
var obj = xref.fetchIfRef(queue.shift());
|
|
if (!isDict(obj)) {
|
|
continue;
|
|
}
|
|
if (obj.has('Kids')) {
|
|
var kids = obj.get('Kids');
|
|
for (i = 0, n = kids.length; i < n; i++) {
|
|
var kid = kids[i];
|
|
assert(!processed.has(kid),
|
|
'Duplicate entry in "' + this._type + '" tree.');
|
|
queue.push(kid);
|
|
processed.put(kid);
|
|
}
|
|
continue;
|
|
}
|
|
var entries = obj.get(this._type);
|
|
if (isArray(entries)) {
|
|
for (i = 0, n = entries.length; i < n; i += 2) {
|
|
dict[xref.fetchIfRef(entries[i])] = xref.fetchIfRef(entries[i + 1]);
|
|
}
|
|
}
|
|
}
|
|
return dict;
|
|
},
|
|
|
|
get: function NameOrNumberTree_get(key) {
|
|
if (!this.root) {
|
|
return null;
|
|
}
|
|
|
|
var xref = this.xref;
|
|
var kidsOrEntries = xref.fetchIfRef(this.root);
|
|
var loopCount = 0;
|
|
var MAX_LEVELS = 10;
|
|
var l, r, m;
|
|
|
|
// Perform a binary search to quickly find the entry that
|
|
// contains the key we are looking for.
|
|
while (kidsOrEntries.has('Kids')) {
|
|
if (++loopCount > MAX_LEVELS) {
|
|
warn('Search depth limit reached for "' + this._type + '" tree.');
|
|
return null;
|
|
}
|
|
|
|
var kids = kidsOrEntries.get('Kids');
|
|
if (!isArray(kids)) {
|
|
return null;
|
|
}
|
|
|
|
l = 0;
|
|
r = kids.length - 1;
|
|
while (l <= r) {
|
|
m = (l + r) >> 1;
|
|
var kid = xref.fetchIfRef(kids[m]);
|
|
var limits = kid.get('Limits');
|
|
|
|
if (key < xref.fetchIfRef(limits[0])) {
|
|
r = m - 1;
|
|
} else if (key > xref.fetchIfRef(limits[1])) {
|
|
l = m + 1;
|
|
} else {
|
|
kidsOrEntries = xref.fetchIfRef(kids[m]);
|
|
break;
|
|
}
|
|
}
|
|
if (l > r) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// If we get here, then we have found the right entry. Now go through the
|
|
// entries in the dictionary until we find the key we're looking for.
|
|
var entries = kidsOrEntries.get(this._type);
|
|
if (isArray(entries)) {
|
|
// Perform a binary search to reduce the lookup time.
|
|
l = 0;
|
|
r = entries.length - 2;
|
|
while (l <= r) {
|
|
// Check only even indices (0, 2, 4, ...) because the
|
|
// odd indices contain the actual data.
|
|
m = (l + r) & ~1;
|
|
var currentKey = xref.fetchIfRef(entries[m]);
|
|
if (key < currentKey) {
|
|
r = m - 2;
|
|
} else if (key > currentKey) {
|
|
l = m + 2;
|
|
} else {
|
|
return xref.fetchIfRef(entries[m + 1]);
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
};
|
|
return NameOrNumberTree;
|
|
})();
|
|
|
|
var NameTree = (function NameTreeClosure() {
|
|
function NameTree(root, xref) {
|
|
this.root = root;
|
|
this.xref = xref;
|
|
this._type = 'Names';
|
|
}
|
|
|
|
Util.inherit(NameTree, NameOrNumberTree, {});
|
|
|
|
return NameTree;
|
|
})();
|
|
|
|
var NumberTree = (function NumberTreeClosure() {
|
|
function NumberTree(root, xref) {
|
|
this.root = root;
|
|
this.xref = xref;
|
|
this._type = 'Nums';
|
|
}
|
|
|
|
Util.inherit(NumberTree, NameOrNumberTree, {});
|
|
|
|
return NumberTree;
|
|
})();
|
|
|
|
/**
|
|
* "A PDF file can refer to the contents of another file by using a File
|
|
* Specification (PDF 1.1)", see the spec (7.11) for more details.
|
|
* NOTE: Only embedded files are supported (as part of the attachments support)
|
|
* TODO: support the 'URL' file system (with caching if !/V), portable
|
|
* collections attributes and related files (/RF)
|
|
*/
|
|
var FileSpec = (function FileSpecClosure() {
|
|
function FileSpec(root, xref) {
|
|
if (!root || !isDict(root)) {
|
|
return;
|
|
}
|
|
this.xref = xref;
|
|
this.root = root;
|
|
if (root.has('FS')) {
|
|
this.fs = root.get('FS');
|
|
}
|
|
this.description = root.has('Desc') ?
|
|
stringToPDFString(root.get('Desc')) :
|
|
'';
|
|
if (root.has('RF')) {
|
|
warn('Related file specifications are not supported');
|
|
}
|
|
this.contentAvailable = true;
|
|
if (!root.has('EF')) {
|
|
this.contentAvailable = false;
|
|
warn('Non-embedded file specifications are not supported');
|
|
}
|
|
}
|
|
|
|
function pickPlatformItem(dict) {
|
|
// Look for the filename in this order:
|
|
// UF, F, Unix, Mac, DOS
|
|
if (dict.has('UF')) {
|
|
return dict.get('UF');
|
|
} else if (dict.has('F')) {
|
|
return dict.get('F');
|
|
} else if (dict.has('Unix')) {
|
|
return dict.get('Unix');
|
|
} else if (dict.has('Mac')) {
|
|
return dict.get('Mac');
|
|
} else if (dict.has('DOS')) {
|
|
return dict.get('DOS');
|
|
}
|
|
return null;
|
|
}
|
|
|
|
FileSpec.prototype = {
|
|
get filename() {
|
|
if (!this._filename && this.root) {
|
|
var filename = pickPlatformItem(this.root) || 'unnamed';
|
|
this._filename = stringToPDFString(filename).
|
|
replace(/\\\\/g, '\\').
|
|
replace(/\\\//g, '/').
|
|
replace(/\\/g, '/');
|
|
}
|
|
return this._filename;
|
|
},
|
|
get content() {
|
|
if (!this.contentAvailable) {
|
|
return null;
|
|
}
|
|
if (!this.contentRef && this.root) {
|
|
this.contentRef = pickPlatformItem(this.root.get('EF'));
|
|
}
|
|
var content = null;
|
|
if (this.contentRef) {
|
|
var xref = this.xref;
|
|
var fileObj = xref.fetchIfRef(this.contentRef);
|
|
if (fileObj && isStream(fileObj)) {
|
|
content = fileObj.getBytes();
|
|
} else {
|
|
warn('Embedded file specification points to non-existing/invalid ' +
|
|
'content');
|
|
}
|
|
} else {
|
|
warn('Embedded file specification does not have a content');
|
|
}
|
|
return content;
|
|
},
|
|
get serializable() {
|
|
return {
|
|
filename: this.filename,
|
|
content: this.content
|
|
};
|
|
}
|
|
};
|
|
return FileSpec;
|
|
})();
|
|
|
|
/**
|
|
* A helper for loading missing data in object graphs. It traverses the graph
|
|
* depth first and queues up any objects that have missing data. Once it has
|
|
* has traversed as many objects that are available it attempts to bundle the
|
|
* missing data requests and then resume from the nodes that weren't ready.
|
|
*
|
|
* NOTE: It provides protection from circular references by keeping track of
|
|
* of loaded references. However, you must be careful not to load any graphs
|
|
* that have references to the catalog or other pages since that will cause the
|
|
* entire PDF document object graph to be traversed.
|
|
*/
|
|
var ObjectLoader = (function() {
|
|
function mayHaveChildren(value) {
|
|
return isRef(value) || isDict(value) || isArray(value) || isStream(value);
|
|
}
|
|
|
|
function addChildren(node, nodesToVisit) {
|
|
var value;
|
|
if (isDict(node) || isStream(node)) {
|
|
var map;
|
|
if (isDict(node)) {
|
|
map = node.map;
|
|
} else {
|
|
map = node.dict.map;
|
|
}
|
|
for (var key in map) {
|
|
value = map[key];
|
|
if (mayHaveChildren(value)) {
|
|
nodesToVisit.push(value);
|
|
}
|
|
}
|
|
} else if (isArray(node)) {
|
|
for (var i = 0, ii = node.length; i < ii; i++) {
|
|
value = node[i];
|
|
if (mayHaveChildren(value)) {
|
|
nodesToVisit.push(value);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
function ObjectLoader(obj, keys, xref) {
|
|
this.obj = obj;
|
|
this.keys = keys;
|
|
this.xref = xref;
|
|
this.refSet = null;
|
|
this.capability = null;
|
|
}
|
|
|
|
ObjectLoader.prototype = {
|
|
load: function ObjectLoader_load() {
|
|
var keys = this.keys;
|
|
this.capability = createPromiseCapability();
|
|
// Don't walk the graph if all the data is already loaded.
|
|
if (!(this.xref.stream instanceof ChunkedStream) ||
|
|
this.xref.stream.getMissingChunks().length === 0) {
|
|
this.capability.resolve();
|
|
return this.capability.promise;
|
|
}
|
|
|
|
this.refSet = new RefSet();
|
|
// Setup the initial nodes to visit.
|
|
var nodesToVisit = [];
|
|
for (var i = 0; i < keys.length; i++) {
|
|
nodesToVisit.push(this.obj[keys[i]]);
|
|
}
|
|
|
|
this._walk(nodesToVisit);
|
|
return this.capability.promise;
|
|
},
|
|
|
|
_walk: function ObjectLoader_walk(nodesToVisit) {
|
|
var nodesToRevisit = [];
|
|
var pendingRequests = [];
|
|
// DFS walk of the object graph.
|
|
while (nodesToVisit.length) {
|
|
var currentNode = nodesToVisit.pop();
|
|
|
|
// Only references or chunked streams can cause missing data exceptions.
|
|
if (isRef(currentNode)) {
|
|
// Skip nodes that have already been visited.
|
|
if (this.refSet.has(currentNode)) {
|
|
continue;
|
|
}
|
|
try {
|
|
var ref = currentNode;
|
|
this.refSet.put(ref);
|
|
currentNode = this.xref.fetch(currentNode);
|
|
} catch (e) {
|
|
if (!(e instanceof MissingDataException)) {
|
|
throw e;
|
|
}
|
|
nodesToRevisit.push(currentNode);
|
|
pendingRequests.push({ begin: e.begin, end: e.end });
|
|
}
|
|
}
|
|
if (currentNode && currentNode.getBaseStreams) {
|
|
var baseStreams = currentNode.getBaseStreams();
|
|
var foundMissingData = false;
|
|
for (var i = 0; i < baseStreams.length; i++) {
|
|
var stream = baseStreams[i];
|
|
if (stream.getMissingChunks && stream.getMissingChunks().length) {
|
|
foundMissingData = true;
|
|
pendingRequests.push({
|
|
begin: stream.start,
|
|
end: stream.end
|
|
});
|
|
}
|
|
}
|
|
if (foundMissingData) {
|
|
nodesToRevisit.push(currentNode);
|
|
}
|
|
}
|
|
|
|
addChildren(currentNode, nodesToVisit);
|
|
}
|
|
|
|
if (pendingRequests.length) {
|
|
this.xref.stream.manager.requestRanges(pendingRequests).then(
|
|
function pendingRequestCallback() {
|
|
nodesToVisit = nodesToRevisit;
|
|
for (var i = 0; i < nodesToRevisit.length; i++) {
|
|
var node = nodesToRevisit[i];
|
|
// Remove any reference nodes from the currrent refset so they
|
|
// aren't skipped when we revist them.
|
|
if (isRef(node)) {
|
|
this.refSet.remove(node);
|
|
}
|
|
}
|
|
this._walk(nodesToVisit);
|
|
}.bind(this), this.capability.reject);
|
|
return;
|
|
}
|
|
// Everything is loaded.
|
|
this.refSet = null;
|
|
this.capability.resolve();
|
|
}
|
|
};
|
|
|
|
return ObjectLoader;
|
|
})();
|
|
|
|
exports.Catalog = Catalog;
|
|
exports.ObjectLoader = ObjectLoader;
|
|
exports.XRef = XRef;
|
|
exports.FileSpec = FileSpec;
|
|
}));
|