81525fd446
There's built-in ESLint rule, see `sort-imports`, to ensure that all `import`-statements are sorted alphabetically, since that often helps with readability. Unfortunately there's no corresponding rule to sort `export`-statements alphabetically, however there's an ESLint plugin which does this; please see https://www.npmjs.com/package/eslint-plugin-sort-exports The only downside here is that it's not automatically fixable, but the re-ordering is a one-time "cost" and the plugin will help maintain a *consistent* ordering of `export`-statements in the future. *Note:* To reduce the possibility of introducing any errors here, the re-ordering was done by simply selecting the relevant lines and then using the built-in sort-functionality of my editor.
2606 lines
76 KiB
JavaScript
2606 lines
76 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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/* eslint-disable no-var */
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import {
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assert,
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bytesToString,
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createPromiseCapability,
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createValidAbsoluteUrl,
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DocumentActionEventType,
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FormatError,
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info,
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InvalidPDFException,
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isBool,
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isNum,
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isString,
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objectSize,
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PermissionFlag,
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shadow,
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stringToPDFString,
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stringToUTF8String,
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unreachable,
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warn,
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} from "../shared/util.js";
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import {
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clearPrimitiveCaches,
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Cmd,
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Dict,
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isCmd,
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isDict,
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isName,
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isRef,
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isRefsEqual,
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isStream,
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Ref,
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RefSet,
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RefSetCache,
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} from "./primitives.js";
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import {
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collectActions,
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MissingDataException,
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toRomanNumerals,
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XRefEntryException,
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XRefParseException,
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} from "./core_utils.js";
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import { Lexer, Parser } from "./parser.js";
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import { CipherTransformFactory } from "./crypto.js";
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import { ColorSpace } from "./colorspace.js";
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import { GlobalImageCache } from "./image_utils.js";
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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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class Catalog {
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constructor(pdfManager, xref) {
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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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if (!isDict(this._catDict)) {
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throw new FormatError("Catalog object is not a dictionary.");
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}
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this.fontCache = new RefSetCache();
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this.builtInCMapCache = new Map();
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this.globalImageCache = new GlobalImageCache();
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this.pageKidsCountCache = new RefSetCache();
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this.nonBlendModesSet = new RefSet();
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}
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get version() {
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const version = this._catDict.get("Version");
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if (!isName(version)) {
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return shadow(this, "version", null);
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}
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return shadow(this, "version", version.name);
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}
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get collection() {
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let collection = null;
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try {
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const obj = this._catDict.get("Collection");
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if (isDict(obj) && obj.size > 0) {
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collection = obj;
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}
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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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info("Cannot fetch Collection entry; assuming no collection is present.");
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}
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return shadow(this, "collection", collection);
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}
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get acroForm() {
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let acroForm = null;
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try {
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const obj = this._catDict.get("AcroForm");
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if (isDict(obj) && obj.size > 0) {
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acroForm = obj;
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}
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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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info("Cannot fetch AcroForm entry; assuming no forms are present.");
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}
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return shadow(this, "acroForm", acroForm);
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}
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get metadata() {
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const 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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const suppressEncryption = !(
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this.xref.encrypt && this.xref.encrypt.encryptMetadata
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);
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const stream = this.xref.fetch(streamRef, suppressEncryption);
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let metadata;
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if (stream && isDict(stream.dict)) {
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const type = stream.dict.get("Type");
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const 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 markInfo() {
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let markInfo = null;
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try {
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markInfo = this._readMarkInfo();
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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 mark info.");
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}
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return shadow(this, "markInfo", markInfo);
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}
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/**
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* @private
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*/
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_readMarkInfo() {
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const obj = this._catDict.get("MarkInfo");
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if (!isDict(obj)) {
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return null;
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}
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const markInfo = Object.assign(Object.create(null), {
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Marked: false,
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UserProperties: false,
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Suspects: false,
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});
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for (const key in markInfo) {
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if (!obj.has(key)) {
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continue;
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}
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const value = obj.get(key);
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if (!isBool(value)) {
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continue;
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}
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markInfo[key] = value;
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}
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return markInfo;
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}
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get toplevelPagesDict() {
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const pagesObj = this._catDict.get("Pages");
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if (!isDict(pagesObj)) {
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throw new FormatError("Invalid top-level pages dictionary.");
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}
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return shadow(this, "toplevelPagesDict", pagesObj);
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}
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get documentOutline() {
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let 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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/**
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* @private
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*/
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_readDocumentOutline() {
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let 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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const root = { items: [] };
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const queue = [{ obj, parent: root }];
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// To avoid recursion, keep track of the already processed items.
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const processed = new RefSet();
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processed.put(obj);
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const xref = this.xref,
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blackColor = new Uint8ClampedArray(3);
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while (queue.length > 0) {
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const i = queue.shift();
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const 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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if (!outlineDict.has("Title")) {
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throw new FormatError("Invalid outline item encountered.");
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}
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const 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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const title = outlineDict.get("Title");
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const flags = outlineDict.get("F") || 0;
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const color = outlineDict.getArray("C");
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const count = outlineDict.get("Count");
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let 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 (
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Array.isArray(color) &&
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color.length === 3 &&
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(color[0] !== 0 || color[1] !== 0 || color[2] !== 0)
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) {
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rgbColor = ColorSpace.singletons.rgb.getRgb(color, 0);
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}
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const 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: Number.isInteger(count) ? count : undefined,
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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, 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, 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 permissions() {
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let permissions = null;
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try {
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permissions = this._readPermissions();
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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 permissions.");
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}
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return shadow(this, "permissions", permissions);
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}
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/**
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* @private
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*/
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_readPermissions() {
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const encrypt = this.xref.trailer.get("Encrypt");
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if (!isDict(encrypt)) {
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return null;
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}
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let flags = encrypt.get("P");
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if (!isNum(flags)) {
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return null;
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}
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// PDF integer objects are represented internally in signed 2's complement
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// form. Therefore, convert the signed decimal integer to a signed 2's
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// complement binary integer so we can use regular bitwise operations on it.
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flags += 2 ** 32;
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const permissions = [];
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for (const key in PermissionFlag) {
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const value = PermissionFlag[key];
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if (flags & value) {
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permissions.push(value);
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}
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}
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return permissions;
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}
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get optionalContentConfig() {
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let config = null;
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try {
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const properties = this._catDict.get("OCProperties");
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if (!properties) {
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return shadow(this, "optionalContentConfig", null);
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}
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const defaultConfig = properties.get("D");
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if (!defaultConfig) {
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return shadow(this, "optionalContentConfig", null);
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}
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const groupsData = properties.get("OCGs");
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if (!Array.isArray(groupsData)) {
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return shadow(this, "optionalContentConfig", null);
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}
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const groups = [];
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const groupRefs = [];
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// Ensure all the optional content groups are valid.
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for (const groupRef of groupsData) {
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if (!isRef(groupRef)) {
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continue;
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}
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groupRefs.push(groupRef);
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const group = this.xref.fetchIfRef(groupRef);
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groups.push({
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id: groupRef.toString(),
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name: isString(group.get("Name"))
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? stringToPDFString(group.get("Name"))
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: null,
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intent: isString(group.get("Intent"))
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? stringToPDFString(group.get("Intent"))
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: null,
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});
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}
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config = this._readOptionalContentConfig(defaultConfig, groupRefs);
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config.groups = groups;
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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 optional content config: ${ex}`);
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}
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return shadow(this, "optionalContentConfig", config);
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}
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_readOptionalContentConfig(config, contentGroupRefs) {
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function parseOnOff(refs) {
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const onParsed = [];
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if (Array.isArray(refs)) {
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for (const value of refs) {
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if (!isRef(value)) {
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continue;
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}
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if (contentGroupRefs.includes(value)) {
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onParsed.push(value.toString());
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}
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}
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}
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return onParsed;
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}
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function parseOrder(refs, nestedLevels = 0) {
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if (!Array.isArray(refs)) {
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return null;
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}
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const order = [];
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for (const value of refs) {
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if (isRef(value) && contentGroupRefs.includes(value)) {
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parsedOrderRefs.put(value); // Handle "hidden" groups, see below.
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order.push(value.toString());
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continue;
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}
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// Handle nested /Order arrays (see e.g. issue 9462 and bug 1240641).
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const nestedOrder = parseNestedOrder(value, nestedLevels);
|
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if (nestedOrder) {
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order.push(nestedOrder);
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}
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}
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if (nestedLevels > 0) {
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return order;
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}
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const hiddenGroups = [];
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for (const groupRef of contentGroupRefs) {
|
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if (parsedOrderRefs.has(groupRef)) {
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continue;
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}
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hiddenGroups.push(groupRef.toString());
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}
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if (hiddenGroups.length) {
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order.push({ name: null, order: hiddenGroups });
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}
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return order;
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}
|
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|
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function parseNestedOrder(ref, nestedLevels) {
|
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if (++nestedLevels > MAX_NESTED_LEVELS) {
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warn("parseNestedOrder - reached MAX_NESTED_LEVELS.");
|
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return null;
|
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}
|
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const value = xref.fetchIfRef(ref);
|
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if (!Array.isArray(value)) {
|
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return null;
|
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}
|
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const nestedName = xref.fetchIfRef(value[0]);
|
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if (typeof nestedName !== "string") {
|
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return null;
|
|
}
|
|
const nestedOrder = parseOrder(value.slice(1), nestedLevels);
|
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if (!nestedOrder || !nestedOrder.length) {
|
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return null;
|
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}
|
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return { name: stringToPDFString(nestedName), order: nestedOrder };
|
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}
|
|
|
|
const xref = this.xref,
|
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parsedOrderRefs = new RefSet(),
|
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MAX_NESTED_LEVELS = 10;
|
|
|
|
return {
|
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name: isString(config.get("Name"))
|
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? stringToPDFString(config.get("Name"))
|
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: null,
|
|
creator: isString(config.get("Creator"))
|
|
? stringToPDFString(config.get("Creator"))
|
|
: null,
|
|
baseState: isName(config.get("BaseState"))
|
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? config.get("BaseState").name
|
|
: null,
|
|
on: parseOnOff(config.get("ON")),
|
|
off: parseOnOff(config.get("OFF")),
|
|
order: parseOrder(config.get("Order")),
|
|
groups: null,
|
|
};
|
|
}
|
|
|
|
get numPages() {
|
|
const obj = this.toplevelPagesDict.get("Count");
|
|
if (!Number.isInteger(obj)) {
|
|
throw new FormatError(
|
|
"Page count in top-level pages dictionary is not an integer."
|
|
);
|
|
}
|
|
return shadow(this, "numPages", obj);
|
|
}
|
|
|
|
get destinations() {
|
|
const obj = this._readDests(),
|
|
dests = Object.create(null);
|
|
if (obj instanceof NameTree) {
|
|
const names = obj.getAll();
|
|
for (const name in names) {
|
|
dests[name] = fetchDestination(names[name]);
|
|
}
|
|
} else if (obj instanceof Dict) {
|
|
obj.forEach(function (key, value) {
|
|
if (value) {
|
|
dests[key] = fetchDestination(value);
|
|
}
|
|
});
|
|
}
|
|
return shadow(this, "destinations", dests);
|
|
}
|
|
|
|
getDestination(destinationId) {
|
|
const obj = this._readDests();
|
|
if (obj instanceof NameTree || obj instanceof Dict) {
|
|
return fetchDestination(obj.get(destinationId) || null);
|
|
}
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* @private
|
|
*/
|
|
_readDests() {
|
|
const obj = this._catDict.get("Names");
|
|
if (obj && obj.has("Dests")) {
|
|
return new NameTree(obj.getRaw("Dests"), this.xref);
|
|
} else if (this._catDict.has("Dests")) {
|
|
// Simple destination dictionary.
|
|
return this._catDict.get("Dests");
|
|
}
|
|
return undefined;
|
|
}
|
|
|
|
get pageLabels() {
|
|
let obj = null;
|
|
try {
|
|
obj = this._readPageLabels();
|
|
} catch (ex) {
|
|
if (ex instanceof MissingDataException) {
|
|
throw ex;
|
|
}
|
|
warn("Unable to read page labels.");
|
|
}
|
|
return shadow(this, "pageLabels", obj);
|
|
}
|
|
|
|
/**
|
|
* @private
|
|
*/
|
|
_readPageLabels() {
|
|
const obj = this._catDict.getRaw("PageLabels");
|
|
if (!obj) {
|
|
return null;
|
|
}
|
|
|
|
const pageLabels = new Array(this.numPages);
|
|
let style = null,
|
|
prefix = "";
|
|
|
|
const numberTree = new NumberTree(obj, this.xref);
|
|
const nums = numberTree.getAll();
|
|
let currentLabel = "",
|
|
currentIndex = 1;
|
|
|
|
for (let i = 0, ii = this.numPages; i < ii; i++) {
|
|
if (i in nums) {
|
|
const labelDict = nums[i];
|
|
if (!isDict(labelDict)) {
|
|
throw new FormatError("PageLabel is not a dictionary.");
|
|
}
|
|
|
|
if (
|
|
labelDict.has("Type") &&
|
|
!isName(labelDict.get("Type"), "PageLabel")
|
|
) {
|
|
throw new FormatError("Invalid type in PageLabel dictionary.");
|
|
}
|
|
|
|
if (labelDict.has("S")) {
|
|
const s = labelDict.get("S");
|
|
if (!isName(s)) {
|
|
throw new FormatError("Invalid style in PageLabel dictionary.");
|
|
}
|
|
style = s.name;
|
|
} else {
|
|
style = null;
|
|
}
|
|
|
|
if (labelDict.has("P")) {
|
|
const p = labelDict.get("P");
|
|
if (!isString(p)) {
|
|
throw new FormatError("Invalid prefix in PageLabel dictionary.");
|
|
}
|
|
prefix = stringToPDFString(p);
|
|
} else {
|
|
prefix = "";
|
|
}
|
|
|
|
if (labelDict.has("St")) {
|
|
const st = labelDict.get("St");
|
|
if (!(Number.isInteger(st) && st >= 1)) {
|
|
throw new FormatError("Invalid start in PageLabel dictionary.");
|
|
}
|
|
currentIndex = st;
|
|
} else {
|
|
currentIndex = 1;
|
|
}
|
|
}
|
|
|
|
switch (style) {
|
|
case "D":
|
|
currentLabel = currentIndex;
|
|
break;
|
|
case "R":
|
|
case "r":
|
|
currentLabel = toRomanNumerals(currentIndex, style === "r");
|
|
break;
|
|
case "A":
|
|
case "a":
|
|
const LIMIT = 26; // Use only the characters A-Z, or a-z.
|
|
const A_UPPER_CASE = 0x41,
|
|
A_LOWER_CASE = 0x61;
|
|
|
|
const baseCharCode = style === "a" ? A_LOWER_CASE : A_UPPER_CASE;
|
|
const letterIndex = currentIndex - 1;
|
|
const character = String.fromCharCode(
|
|
baseCharCode + (letterIndex % LIMIT)
|
|
);
|
|
const charBuf = [];
|
|
for (let j = 0, jj = (letterIndex / LIMIT) | 0; j <= jj; j++) {
|
|
charBuf.push(character);
|
|
}
|
|
currentLabel = charBuf.join("");
|
|
break;
|
|
default:
|
|
if (style) {
|
|
throw new FormatError(
|
|
`Invalid style "${style}" in PageLabel dictionary.`
|
|
);
|
|
}
|
|
currentLabel = "";
|
|
}
|
|
|
|
pageLabels[i] = prefix + currentLabel;
|
|
currentIndex++;
|
|
}
|
|
return pageLabels;
|
|
}
|
|
|
|
get pageLayout() {
|
|
const obj = this._catDict.get("PageLayout");
|
|
// Purposely use a non-standard default value, rather than 'SinglePage', to
|
|
// allow differentiating between `undefined` and /SinglePage since that does
|
|
// affect the Scroll mode (continuous/non-continuous) used in Adobe Reader.
|
|
let pageLayout = "";
|
|
|
|
if (isName(obj)) {
|
|
switch (obj.name) {
|
|
case "SinglePage":
|
|
case "OneColumn":
|
|
case "TwoColumnLeft":
|
|
case "TwoColumnRight":
|
|
case "TwoPageLeft":
|
|
case "TwoPageRight":
|
|
pageLayout = obj.name;
|
|
}
|
|
}
|
|
return shadow(this, "pageLayout", pageLayout);
|
|
}
|
|
|
|
get pageMode() {
|
|
const obj = this._catDict.get("PageMode");
|
|
let pageMode = "UseNone"; // Default value.
|
|
|
|
if (isName(obj)) {
|
|
switch (obj.name) {
|
|
case "UseNone":
|
|
case "UseOutlines":
|
|
case "UseThumbs":
|
|
case "FullScreen":
|
|
case "UseOC":
|
|
case "UseAttachments":
|
|
pageMode = obj.name;
|
|
}
|
|
}
|
|
return shadow(this, "pageMode", pageMode);
|
|
}
|
|
|
|
get viewerPreferences() {
|
|
const ViewerPreferencesValidators = {
|
|
HideToolbar: isBool,
|
|
HideMenubar: isBool,
|
|
HideWindowUI: isBool,
|
|
FitWindow: isBool,
|
|
CenterWindow: isBool,
|
|
DisplayDocTitle: isBool,
|
|
NonFullScreenPageMode: isName,
|
|
Direction: isName,
|
|
ViewArea: isName,
|
|
ViewClip: isName,
|
|
PrintArea: isName,
|
|
PrintClip: isName,
|
|
PrintScaling: isName,
|
|
Duplex: isName,
|
|
PickTrayByPDFSize: isBool,
|
|
PrintPageRange: Array.isArray,
|
|
NumCopies: Number.isInteger,
|
|
};
|
|
|
|
const obj = this._catDict.get("ViewerPreferences");
|
|
let prefs = null;
|
|
|
|
if (isDict(obj)) {
|
|
for (const key in ViewerPreferencesValidators) {
|
|
if (!obj.has(key)) {
|
|
continue;
|
|
}
|
|
const value = obj.get(key);
|
|
// Make sure the (standard) value conforms to the specification.
|
|
if (!ViewerPreferencesValidators[key](value)) {
|
|
info(`Bad value in ViewerPreferences for "${key}".`);
|
|
continue;
|
|
}
|
|
let prefValue;
|
|
|
|
switch (key) {
|
|
case "NonFullScreenPageMode":
|
|
switch (value.name) {
|
|
case "UseNone":
|
|
case "UseOutlines":
|
|
case "UseThumbs":
|
|
case "UseOC":
|
|
prefValue = value.name;
|
|
break;
|
|
default:
|
|
prefValue = "UseNone";
|
|
}
|
|
break;
|
|
case "Direction":
|
|
switch (value.name) {
|
|
case "L2R":
|
|
case "R2L":
|
|
prefValue = value.name;
|
|
break;
|
|
default:
|
|
prefValue = "L2R";
|
|
}
|
|
break;
|
|
case "ViewArea":
|
|
case "ViewClip":
|
|
case "PrintArea":
|
|
case "PrintClip":
|
|
switch (value.name) {
|
|
case "MediaBox":
|
|
case "CropBox":
|
|
case "BleedBox":
|
|
case "TrimBox":
|
|
case "ArtBox":
|
|
prefValue = value.name;
|
|
break;
|
|
default:
|
|
prefValue = "CropBox";
|
|
}
|
|
break;
|
|
case "PrintScaling":
|
|
switch (value.name) {
|
|
case "None":
|
|
case "AppDefault":
|
|
prefValue = value.name;
|
|
break;
|
|
default:
|
|
prefValue = "AppDefault";
|
|
}
|
|
break;
|
|
case "Duplex":
|
|
switch (value.name) {
|
|
case "Simplex":
|
|
case "DuplexFlipShortEdge":
|
|
case "DuplexFlipLongEdge":
|
|
prefValue = value.name;
|
|
break;
|
|
default:
|
|
prefValue = "None";
|
|
}
|
|
break;
|
|
case "PrintPageRange":
|
|
const length = value.length;
|
|
if (length % 2 !== 0) {
|
|
// The number of elements must be even.
|
|
break;
|
|
}
|
|
const isValid = value.every((page, i, arr) => {
|
|
return (
|
|
Number.isInteger(page) &&
|
|
page > 0 &&
|
|
(i === 0 || page >= arr[i - 1]) &&
|
|
page <= this.numPages
|
|
);
|
|
});
|
|
if (isValid) {
|
|
prefValue = value;
|
|
}
|
|
break;
|
|
case "NumCopies":
|
|
if (value > 0) {
|
|
prefValue = value;
|
|
}
|
|
break;
|
|
default:
|
|
if (typeof value !== "boolean") {
|
|
throw new FormatError(
|
|
`viewerPreferences - expected a boolean value for: ${key}`
|
|
);
|
|
}
|
|
prefValue = value;
|
|
}
|
|
|
|
if (prefValue !== undefined) {
|
|
if (!prefs) {
|
|
prefs = Object.create(null);
|
|
}
|
|
prefs[key] = prefValue;
|
|
} else {
|
|
info(`Bad value in ViewerPreferences for "${key}".`);
|
|
}
|
|
}
|
|
}
|
|
return shadow(this, "viewerPreferences", prefs);
|
|
}
|
|
|
|
/**
|
|
* NOTE: "JavaScript" actions are, for now, handled by `get javaScript` below.
|
|
*/
|
|
get openAction() {
|
|
const obj = this._catDict.get("OpenAction");
|
|
const openAction = Object.create(null);
|
|
|
|
if (isDict(obj)) {
|
|
// Convert the OpenAction dictionary into a format that works with
|
|
// `parseDestDictionary`, to avoid having to re-implement those checks.
|
|
const destDict = new Dict(this.xref);
|
|
destDict.set("A", obj);
|
|
|
|
const resultObj = { url: null, dest: null, action: null };
|
|
Catalog.parseDestDictionary({ destDict, resultObj });
|
|
|
|
if (Array.isArray(resultObj.dest)) {
|
|
openAction.dest = resultObj.dest;
|
|
} else if (resultObj.action) {
|
|
openAction.action = resultObj.action;
|
|
}
|
|
} else if (Array.isArray(obj)) {
|
|
openAction.dest = obj;
|
|
}
|
|
return shadow(
|
|
this,
|
|
"openAction",
|
|
objectSize(openAction) > 0 ? openAction : null
|
|
);
|
|
}
|
|
|
|
get attachments() {
|
|
const obj = this._catDict.get("Names");
|
|
let attachments = null;
|
|
|
|
if (obj && obj.has("EmbeddedFiles")) {
|
|
const nameTree = new NameTree(obj.getRaw("EmbeddedFiles"), this.xref);
|
|
const names = nameTree.getAll();
|
|
for (const name in names) {
|
|
const fs = new FileSpec(names[name], this.xref);
|
|
if (!attachments) {
|
|
attachments = Object.create(null);
|
|
}
|
|
attachments[stringToPDFString(name)] = fs.serializable;
|
|
}
|
|
}
|
|
return shadow(this, "attachments", attachments);
|
|
}
|
|
|
|
_collectJavaScript() {
|
|
const obj = this._catDict.get("Names");
|
|
|
|
let javaScript = null;
|
|
function appendIfJavaScriptDict(name, jsDict) {
|
|
const type = jsDict.get("S");
|
|
if (!isName(type, "JavaScript")) {
|
|
return;
|
|
}
|
|
|
|
let js = jsDict.get("JS");
|
|
if (isStream(js)) {
|
|
js = bytesToString(js.getBytes());
|
|
} else if (!isString(js)) {
|
|
return;
|
|
}
|
|
|
|
if (javaScript === null) {
|
|
javaScript = Object.create(null);
|
|
}
|
|
javaScript[name] = stringToPDFString(js);
|
|
}
|
|
|
|
if (obj && obj.has("JavaScript")) {
|
|
const nameTree = new NameTree(obj.getRaw("JavaScript"), this.xref);
|
|
const names = nameTree.getAll();
|
|
for (const name in names) {
|
|
// We don't use most JavaScript in PDF documents. This code is
|
|
// defensive so we don't cause errors on document load.
|
|
const jsDict = names[name];
|
|
if (isDict(jsDict)) {
|
|
appendIfJavaScriptDict(name, jsDict);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Append OpenAction "JavaScript" actions to the JavaScript array.
|
|
const openAction = this._catDict.get("OpenAction");
|
|
if (isDict(openAction) && isName(openAction.get("S"), "JavaScript")) {
|
|
appendIfJavaScriptDict("OpenAction", openAction);
|
|
}
|
|
|
|
return javaScript;
|
|
}
|
|
|
|
get javaScript() {
|
|
const javaScript = this._collectJavaScript();
|
|
return shadow(
|
|
this,
|
|
"javaScript",
|
|
javaScript ? Object.values(javaScript) : null
|
|
);
|
|
}
|
|
|
|
get jsActions() {
|
|
const js = this._collectJavaScript();
|
|
let actions = collectActions(
|
|
this.xref,
|
|
this._catDict,
|
|
DocumentActionEventType
|
|
);
|
|
|
|
if (!actions && js) {
|
|
actions = Object.create(null);
|
|
}
|
|
if (actions && js) {
|
|
for (const [key, val] of Object.entries(js)) {
|
|
if (key in actions) {
|
|
actions[key].push(val);
|
|
} else {
|
|
actions[key] = [val];
|
|
}
|
|
}
|
|
}
|
|
|
|
return shadow(this, "jsActions", actions);
|
|
}
|
|
|
|
fontFallback(id, handler) {
|
|
const promises = [];
|
|
this.fontCache.forEach(function (promise) {
|
|
promises.push(promise);
|
|
});
|
|
|
|
return Promise.all(promises).then(translatedFonts => {
|
|
for (const translatedFont of translatedFonts) {
|
|
if (translatedFont.loadedName === id) {
|
|
translatedFont.fallback(handler);
|
|
return;
|
|
}
|
|
}
|
|
});
|
|
}
|
|
|
|
cleanup(manuallyTriggered = false) {
|
|
clearPrimitiveCaches();
|
|
this.globalImageCache.clear(/* onlyData = */ manuallyTriggered);
|
|
this.pageKidsCountCache.clear();
|
|
this.nonBlendModesSet.clear();
|
|
|
|
const promises = [];
|
|
this.fontCache.forEach(function (promise) {
|
|
promises.push(promise);
|
|
});
|
|
|
|
return Promise.all(promises).then(translatedFonts => {
|
|
for (const { dict } of translatedFonts) {
|
|
delete dict.cacheKey;
|
|
}
|
|
this.fontCache.clear();
|
|
this.builtInCMapCache.clear();
|
|
});
|
|
}
|
|
|
|
getPageDict(pageIndex) {
|
|
const capability = createPromiseCapability();
|
|
const nodesToVisit = [this._catDict.getRaw("Pages")];
|
|
const visitedNodes = new RefSet();
|
|
const xref = this.xref,
|
|
pageKidsCountCache = this.pageKidsCountCache;
|
|
let count,
|
|
currentPageIndex = 0;
|
|
|
|
function next() {
|
|
while (nodesToVisit.length) {
|
|
const currentNode = nodesToVisit.pop();
|
|
|
|
if (isRef(currentNode)) {
|
|
count = pageKidsCountCache.get(currentNode);
|
|
// Skip nodes where the page can't be.
|
|
if (count > 0 && currentPageIndex + count < pageIndex) {
|
|
currentPageIndex += count;
|
|
continue;
|
|
}
|
|
// Prevent circular references in the /Pages tree.
|
|
if (visitedNodes.has(currentNode)) {
|
|
capability.reject(
|
|
new FormatError("Pages tree contains circular reference.")
|
|
);
|
|
return;
|
|
}
|
|
visitedNodes.put(currentNode);
|
|
|
|
xref.fetchAsync(currentNode).then(function (obj) {
|
|
if (isDict(obj, "Page") || (isDict(obj) && !obj.has("Kids"))) {
|
|
if (pageIndex === currentPageIndex) {
|
|
// Cache the Page reference, since it can *greatly* improve
|
|
// performance by reducing redundant lookups in long documents
|
|
// where all nodes are found at *one* level of the tree.
|
|
if (currentNode && !pageKidsCountCache.has(currentNode)) {
|
|
pageKidsCountCache.put(currentNode, 1);
|
|
}
|
|
capability.resolve([obj, currentNode]);
|
|
} else {
|
|
currentPageIndex++;
|
|
next();
|
|
}
|
|
return;
|
|
}
|
|
nodesToVisit.push(obj);
|
|
next();
|
|
}, capability.reject);
|
|
return;
|
|
}
|
|
|
|
// Must be a child page dictionary.
|
|
if (!isDict(currentNode)) {
|
|
capability.reject(
|
|
new FormatError(
|
|
"Page dictionary kid reference points to wrong type of object."
|
|
)
|
|
);
|
|
return;
|
|
}
|
|
|
|
count = currentNode.get("Count");
|
|
if (Number.isInteger(count) && count >= 0) {
|
|
// Cache the Kids count, since it can reduce redundant lookups in
|
|
// documents where all nodes are found at *one* level of the tree.
|
|
const 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;
|
|
}
|
|
}
|
|
|
|
const kids = currentNode.get("Kids");
|
|
if (!Array.isArray(kids)) {
|
|
// Prevent errors in corrupt PDF documents that violate the
|
|
// specification by *inlining* Page dicts directly in the Kids
|
|
// array, rather than using indirect objects (fixes issue9540.pdf).
|
|
if (
|
|
isName(currentNode.get("Type"), "Page") ||
|
|
(!currentNode.has("Type") && currentNode.has("Contents"))
|
|
) {
|
|
if (currentPageIndex === pageIndex) {
|
|
capability.resolve([currentNode, null]);
|
|
return;
|
|
}
|
|
currentPageIndex++;
|
|
continue;
|
|
}
|
|
|
|
capability.reject(
|
|
new FormatError("Page dictionary kids object is not an array.")
|
|
);
|
|
return;
|
|
}
|
|
|
|
// 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 (let last = kids.length - 1; last >= 0; last--) {
|
|
nodesToVisit.push(kids[last]);
|
|
}
|
|
}
|
|
capability.reject(new Error(`Page index ${pageIndex} not found.`));
|
|
}
|
|
next();
|
|
return capability.promise;
|
|
}
|
|
|
|
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.
|
|
const xref = this.xref;
|
|
|
|
function pagesBeforeRef(kidRef) {
|
|
let total = 0,
|
|
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 FormatError(
|
|
"The reference does not point to a /Page dictionary."
|
|
);
|
|
}
|
|
if (!node) {
|
|
return null;
|
|
}
|
|
if (!isDict(node)) {
|
|
throw new FormatError("Node must be a dictionary.");
|
|
}
|
|
parentRef = node.getRaw("Parent");
|
|
return node.getAsync("Parent");
|
|
})
|
|
.then(function (parent) {
|
|
if (!parent) {
|
|
return null;
|
|
}
|
|
if (!isDict(parent)) {
|
|
throw new FormatError("Parent must be a dictionary.");
|
|
}
|
|
return parent.getAsync("Kids");
|
|
})
|
|
.then(function (kids) {
|
|
if (!kids) {
|
|
return null;
|
|
}
|
|
|
|
const kidPromises = [];
|
|
let found = false;
|
|
for (let i = 0, ii = kids.length; i < ii; i++) {
|
|
const kid = kids[i];
|
|
if (!isRef(kid)) {
|
|
throw new FormatError("Kid must be a reference.");
|
|
}
|
|
if (isRefsEqual(kid, kidRef)) {
|
|
found = true;
|
|
break;
|
|
}
|
|
kidPromises.push(
|
|
xref.fetchAsync(kid).then(function (obj) {
|
|
if (!isDict(obj)) {
|
|
throw new FormatError("Kid node must be a dictionary.");
|
|
}
|
|
if (obj.has("Count")) {
|
|
total += obj.get("Count");
|
|
} else {
|
|
// Page leaf node.
|
|
total++;
|
|
}
|
|
})
|
|
);
|
|
}
|
|
if (!found) {
|
|
throw new FormatError("Kid reference not found in parent's kids.");
|
|
}
|
|
return Promise.all(kidPromises).then(function () {
|
|
return [total, parentRef];
|
|
});
|
|
});
|
|
}
|
|
|
|
let total = 0;
|
|
function next(ref) {
|
|
return pagesBeforeRef(ref).then(function (args) {
|
|
if (!args) {
|
|
return total;
|
|
}
|
|
const [count, parentRef] = args;
|
|
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] - 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
|
|
*/
|
|
static parseDestDictionary(params) {
|
|
// Lets URLs beginning with 'www.' default to using the 'http://' protocol.
|
|
function addDefaultProtocolToUrl(url) {
|
|
return url.startsWith("www.") ? `http://${url}` : 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;
|
|
}
|
|
}
|
|
|
|
const destDict = params.destDict;
|
|
if (!isDict(destDict)) {
|
|
warn("parseDestDictionary: `destDict` must be a dictionary.");
|
|
return;
|
|
}
|
|
const resultObj = params.resultObj;
|
|
if (typeof resultObj !== "object") {
|
|
warn("parseDestDictionary: `resultObj` must be an object.");
|
|
return;
|
|
}
|
|
const docBaseUrl = params.docBaseUrl || null;
|
|
|
|
let action = destDict.get("A"),
|
|
url,
|
|
dest;
|
|
if (!isDict(action)) {
|
|
if (destDict.has("Dest")) {
|
|
// A /Dest entry should *only* contain a Name or an Array, but some bad
|
|
// PDF generators ignore that and treat it as an /A entry.
|
|
action = destDict.get("Dest");
|
|
} else {
|
|
action = destDict.get("AA");
|
|
if (isDict(action)) {
|
|
if (action.has("D")) {
|
|
// MouseDown
|
|
action = action.get("D");
|
|
} else if (action.has("U")) {
|
|
// MouseUp
|
|
action = action.get("U");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (isDict(action)) {
|
|
const actionType = action.get("S");
|
|
if (!isName(actionType)) {
|
|
warn("parseDestDictionary: Invalid type in Action dictionary.");
|
|
return;
|
|
}
|
|
const actionName = actionType.name;
|
|
|
|
switch (actionName) {
|
|
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":
|
|
const 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.
|
|
let remoteDest = action.get("D");
|
|
if (remoteDest) {
|
|
if (isName(remoteDest)) {
|
|
remoteDest = remoteDest.name;
|
|
}
|
|
if (isString(url)) {
|
|
const baseUrl = url.split("#")[0];
|
|
if (isString(remoteDest)) {
|
|
url = baseUrl + "#" + remoteDest;
|
|
} else if (Array.isArray(remoteDest)) {
|
|
url = baseUrl + "#" + JSON.stringify(remoteDest);
|
|
}
|
|
}
|
|
}
|
|
// The 'NewWindow' property, equal to `LinkTarget.BLANK`.
|
|
const newWindow = action.get("NewWindow");
|
|
if (isBool(newWindow)) {
|
|
resultObj.newWindow = newWindow;
|
|
}
|
|
break;
|
|
|
|
case "Named":
|
|
const namedAction = action.get("N");
|
|
if (isName(namedAction)) {
|
|
resultObj.action = namedAction.name;
|
|
}
|
|
break;
|
|
|
|
case "JavaScript":
|
|
const jsAction = action.get("JS");
|
|
let 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:
|
|
// - window.open('http://example.com')
|
|
// - app.launchURL('http://example.com', true)
|
|
const URL_OPEN_METHODS = ["app.launchURL", "window.open"];
|
|
const regex = new RegExp(
|
|
"^\\s*(" +
|
|
URL_OPEN_METHODS.join("|").split(".").join("\\.") +
|
|
")\\((?:'|\")([^'\"]*)(?:'|\")(?:,\\s*(\\w+)\\)|\\))",
|
|
"i"
|
|
);
|
|
|
|
const 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(`parseDestDictionary: unsupported action type "${actionName}".`);
|
|
break;
|
|
}
|
|
} else if (destDict.has("Dest")) {
|
|
// Simple destination.
|
|
dest = destDict.get("Dest");
|
|
}
|
|
|
|
if (isString(url)) {
|
|
url = tryConvertUrlEncoding(url);
|
|
const absoluteUrl = createValidAbsoluteUrl(url, docBaseUrl);
|
|
if (absoluteUrl) {
|
|
resultObj.url = absoluteUrl.href;
|
|
}
|
|
resultObj.unsafeUrl = url;
|
|
}
|
|
if (dest) {
|
|
if (isName(dest)) {
|
|
dest = dest.name;
|
|
}
|
|
if (isString(dest) || Array.isArray(dest)) {
|
|
resultObj.dest = dest;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
var XRef = (function XRefClosure() {
|
|
// eslint-disable-next-line no-shadow
|
|
function XRef(stream, pdfManager) {
|
|
this.stream = stream;
|
|
this.pdfManager = pdfManager;
|
|
this.entries = [];
|
|
this.xrefstms = Object.create(null);
|
|
this._cacheMap = new Map(); // Prepare the XRef cache.
|
|
this.stats = {
|
|
streamTypes: Object.create(null),
|
|
fontTypes: Object.create(null),
|
|
};
|
|
this._newRefNum = null;
|
|
}
|
|
|
|
XRef.prototype = {
|
|
getNewRef: function XRef_getNewRef() {
|
|
if (this._newRefNum === null) {
|
|
this._newRefNum = this.entries.length;
|
|
}
|
|
return Ref.get(this._newRefNum++, 0);
|
|
},
|
|
|
|
resetNewRef: function XRef_resetNewRef() {
|
|
this._newRefNum = null;
|
|
},
|
|
|
|
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;
|
|
|
|
let encrypt;
|
|
try {
|
|
encrypt = trailerDict.get("Encrypt");
|
|
} catch (ex) {
|
|
if (ex instanceof MissingDataException) {
|
|
throw ex;
|
|
}
|
|
warn(`XRef.parse - Invalid "Encrypt" reference: "${ex}".`);
|
|
}
|
|
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, and do some basic validation.
|
|
let root;
|
|
try {
|
|
root = trailerDict.get("Root");
|
|
} catch (ex) {
|
|
if (ex instanceof MissingDataException) {
|
|
throw ex;
|
|
}
|
|
warn(`XRef.parse - Invalid "Root" reference: "${ex}".`);
|
|
}
|
|
if (isDict(root) && root.has("Pages")) {
|
|
this.root = root;
|
|
} else {
|
|
if (!recoveryMode) {
|
|
throw new XRefParseException();
|
|
}
|
|
throw new FormatError("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")) {
|
|
throw new FormatError(
|
|
"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)) {
|
|
throw new FormatError(
|
|
"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 (!Number.isInteger(first) || !Number.isInteger(count)) {
|
|
throw new FormatError(
|
|
"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 (type instanceof Cmd) {
|
|
switch (type.cmd) {
|
|
case "f":
|
|
entry.free = true;
|
|
break;
|
|
case "n":
|
|
entry.uncompressed = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Validate entry obj
|
|
if (
|
|
!Number.isInteger(entry.offset) ||
|
|
!Number.isInteger(entry.gen) ||
|
|
!(entry.free || entry.uncompressed)
|
|
) {
|
|
throw new FormatError(
|
|
`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) {
|
|
throw new FormatError("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,
|
|
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 (!Number.isInteger(first) || !Number.isInteger(n)) {
|
|
throw new FormatError(`Invalid XRef range fields: ${first}, ${n}`);
|
|
}
|
|
if (
|
|
!Number.isInteger(typeFieldWidth) ||
|
|
!Number.isInteger(offsetFieldWidth) ||
|
|
!Number.isInteger(generationFieldWidth)
|
|
) {
|
|
throw new FormatError(
|
|
`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:
|
|
throw new FormatError(`Invalid XRef entry type: ${type}`);
|
|
}
|
|
if (!this.entries[first + i]) {
|
|
this.entries[first + i] = entry;
|
|
}
|
|
}
|
|
|
|
streamState.entryNum = 0;
|
|
streamState.streamPos = stream.pos;
|
|
entryRanges.splice(0, 2);
|
|
}
|
|
},
|
|
|
|
indexObjects: function XRef_indexObjects() {
|
|
// Simple scan through the PDF content to find objects,
|
|
// trailers and XRef streams.
|
|
var TAB = 0x9,
|
|
LF = 0xa,
|
|
CR = 0xd,
|
|
SPACE = 0x20;
|
|
var PERCENT = 0x25,
|
|
LT = 0x3c;
|
|
|
|
function readToken(data, offset) {
|
|
var token = "",
|
|
ch = data[offset];
|
|
while (ch !== LF && ch !== CR && ch !== LT) {
|
|
if (++offset >= data.length) {
|
|
break;
|
|
}
|
|
token += String.fromCharCode(ch);
|
|
ch = data[offset];
|
|
}
|
|
return token;
|
|
}
|
|
function skipUntil(data, offset, what) {
|
|
var length = what.length,
|
|
dataLength = data.length;
|
|
var skipped = 0;
|
|
// finding byte sequence
|
|
while (offset < dataLength) {
|
|
var i = 0;
|
|
while (i < length && data[offset + i] === what[i]) {
|
|
++i;
|
|
}
|
|
if (i >= length) {
|
|
break; // sequence found
|
|
}
|
|
offset++;
|
|
skipped++;
|
|
}
|
|
return skipped;
|
|
}
|
|
var objRegExp = /^(\d+)\s+(\d+)\s+obj\b/;
|
|
const endobjRegExp = /\bendobj[\b\s]$/;
|
|
const nestedObjRegExp = /\s+(\d+\s+\d+\s+obj[\b\s<])$/;
|
|
const CHECK_CONTENT_LENGTH = 25;
|
|
|
|
var trailerBytes = new Uint8Array([116, 114, 97, 105, 108, 101, 114]);
|
|
// prettier-ignore
|
|
var startxrefBytes = new Uint8Array([115, 116, 97, 114, 116, 120, 114,
|
|
101, 102]);
|
|
const objBytes = new Uint8Array([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.startsWith("xref") &&
|
|
(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))) {
|
|
const num = m[1] | 0,
|
|
gen = m[2] | 0;
|
|
if (!this.entries[num] || this.entries[num].gen === gen) {
|
|
this.entries[num] = {
|
|
offset: position - stream.start,
|
|
gen,
|
|
uncompressed: true,
|
|
};
|
|
}
|
|
let contentLength,
|
|
startPos = position + token.length;
|
|
|
|
// Find the next "obj" string, rather than "endobj", to ensure that
|
|
// we won't skip over a new 'obj' operator in corrupt files where
|
|
// 'endobj' operators are missing (fixes issue9105_reduced.pdf).
|
|
while (startPos < buffer.length) {
|
|
const endPos = startPos + skipUntil(buffer, startPos, objBytes) + 4;
|
|
contentLength = endPos - position;
|
|
|
|
const checkPos = Math.max(endPos - CHECK_CONTENT_LENGTH, startPos);
|
|
const tokenStr = bytesToString(buffer.subarray(checkPos, endPos));
|
|
|
|
// Check if the current object ends with an 'endobj' operator.
|
|
if (endobjRegExp.test(tokenStr)) {
|
|
break;
|
|
} else {
|
|
// Check if an "obj" occurrence is actually a new object,
|
|
// i.e. the current object is missing the 'endobj' operator.
|
|
const objToken = nestedObjRegExp.exec(tokenStr);
|
|
|
|
if (objToken && objToken[1]) {
|
|
warn(
|
|
'indexObjects: Found new "obj" inside of another "obj", ' +
|
|
'caused by missing "endobj" -- trying to recover.'
|
|
);
|
|
contentLength -= objToken[1].length;
|
|
break;
|
|
}
|
|
}
|
|
startPos = endPos;
|
|
}
|
|
const 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.startsWith("trailer") &&
|
|
(token.length === 7 || /\s/.test(token[7]))
|
|
) {
|
|
trailers.push(position);
|
|
position += skipUntil(buffer, position, startxrefBytes);
|
|
} else {
|
|
position += token.length + 1;
|
|
}
|
|
}
|
|
// reading XRef streams
|
|
for (let i = 0, ii = xrefStms.length; i < ii; ++i) {
|
|
this.startXRefQueue.push(xrefStms[i]);
|
|
this.readXRef(/* recoveryMode */ true);
|
|
}
|
|
// finding main trailer
|
|
let trailerDict;
|
|
for (let i = 0, ii = trailers.length; i < ii; ++i) {
|
|
stream.pos = trailers[i];
|
|
const parser = new Parser({
|
|
lexer: new Lexer(stream),
|
|
xref: this,
|
|
allowStreams: true,
|
|
recoveryMode: true,
|
|
});
|
|
var obj = parser.getObj();
|
|
if (!isCmd(obj, "trailer")) {
|
|
continue;
|
|
}
|
|
// read the trailer dictionary
|
|
const dict = parser.getObj();
|
|
if (!isDict(dict)) {
|
|
continue;
|
|
}
|
|
// Do some basic validation of the trailer/root dictionary candidate.
|
|
try {
|
|
const rootDict = dict.get("Root");
|
|
if (!(rootDict instanceof Dict)) {
|
|
continue;
|
|
}
|
|
const pagesDict = rootDict.get("Pages");
|
|
if (!(pagesDict instanceof Dict)) {
|
|
continue;
|
|
}
|
|
const pagesCount = pagesDict.get("Count");
|
|
if (!Number.isInteger(pagesCount)) {
|
|
continue;
|
|
}
|
|
// The top-level /Pages dictionary isn't obviously corrupt.
|
|
} catch (ex) {
|
|
if (ex instanceof MissingDataException) {
|
|
throw ex;
|
|
}
|
|
continue;
|
|
}
|
|
// taking the first one with 'ID'
|
|
if (dict.has("ID")) {
|
|
return dict;
|
|
}
|
|
// The current dictionary is a candidate, but continue searching.
|
|
trailerDict = dict;
|
|
}
|
|
// No trailer with 'ID', taking last one (if exists).
|
|
if (trailerDict) {
|
|
return trailerDict;
|
|
}
|
|
// nothing helps
|
|
throw new InvalidPDFException("Invalid PDF structure.");
|
|
},
|
|
|
|
readXRef: function XRef_readXRef(recoveryMode) {
|
|
var stream = this.stream;
|
|
// Keep track of already parsed XRef tables, to prevent an infinite loop
|
|
// when parsing corrupt PDF files where e.g. the /Prev entries create a
|
|
// circular dependency between tables (fixes bug1393476.pdf).
|
|
const startXRefParsedCache = Object.create(null);
|
|
|
|
try {
|
|
while (this.startXRefQueue.length) {
|
|
var startXRef = this.startXRefQueue[0];
|
|
|
|
if (startXRefParsedCache[startXRef]) {
|
|
warn("readXRef - skipping XRef table since it was already parsed.");
|
|
this.startXRefQueue.shift();
|
|
continue;
|
|
}
|
|
startXRefParsedCache[startXRef] = true;
|
|
|
|
stream.pos = startXRef + stream.start;
|
|
|
|
const parser = new Parser({
|
|
lexer: new Lexer(stream),
|
|
xref: this,
|
|
allowStreams: true,
|
|
});
|
|
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 (Number.isInteger(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 (Number.isInteger(obj)) {
|
|
// Parse in-stream XRef
|
|
if (
|
|
!Number.isInteger(parser.getObj()) ||
|
|
!isCmd(parser.getObj(), "obj") ||
|
|
!isStream((obj = parser.getObj()))
|
|
) {
|
|
throw new FormatError("Invalid XRef stream");
|
|
}
|
|
dict = this.processXRefStream(obj);
|
|
if (!this.topDict) {
|
|
this.topDict = dict;
|
|
}
|
|
if (!dict) {
|
|
throw new FormatError("Failed to read XRef stream");
|
|
}
|
|
} else {
|
|
throw new FormatError("Invalid XRef stream header");
|
|
}
|
|
|
|
// Recursively get previous dictionary, if any
|
|
obj = dict.get("Prev");
|
|
if (Number.isInteger(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 undefined;
|
|
}
|
|
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 (obj instanceof Ref) {
|
|
return this.fetch(obj, suppressEncryption);
|
|
}
|
|
return obj;
|
|
},
|
|
|
|
fetch: function XRef_fetch(ref, suppressEncryption) {
|
|
if (!(ref instanceof Ref)) {
|
|
throw new Error("ref object is not a reference");
|
|
}
|
|
const num = ref.num;
|
|
|
|
// The XRef cache is populated with objects which are obtained through
|
|
// `Parser.getObj`, and indirectly via `Lexer.getObj`. Neither of these
|
|
// methods should ever return `undefined` (note the `assert` calls below).
|
|
const cacheEntry = this._cacheMap.get(num);
|
|
if (cacheEntry !== undefined) {
|
|
// 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;
|
|
}
|
|
let xrefEntry = this.getEntry(num);
|
|
|
|
if (xrefEntry === null) {
|
|
// The referenced entry can be free.
|
|
this._cacheMap.set(num, xrefEntry);
|
|
return xrefEntry;
|
|
}
|
|
|
|
if (xrefEntry.uncompressed) {
|
|
xrefEntry = this.fetchUncompressed(ref, xrefEntry, suppressEncryption);
|
|
} else {
|
|
xrefEntry = this.fetchCompressed(ref, xrefEntry, suppressEncryption);
|
|
}
|
|
if (isDict(xrefEntry)) {
|
|
xrefEntry.objId = ref.toString();
|
|
} else if (isStream(xrefEntry)) {
|
|
xrefEntry.dict.objId = ref.toString();
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
fetchUncompressed(ref, xrefEntry, suppressEncryption = false) {
|
|
var gen = ref.gen;
|
|
var num = ref.num;
|
|
if (xrefEntry.gen !== gen) {
|
|
throw new XRefEntryException(`Inconsistent generation in XRef: ${ref}`);
|
|
}
|
|
var stream = this.stream.makeSubStream(
|
|
xrefEntry.offset + this.stream.start
|
|
);
|
|
const parser = new Parser({
|
|
lexer: new Lexer(stream),
|
|
xref: this,
|
|
allowStreams: true,
|
|
});
|
|
var obj1 = parser.getObj();
|
|
var obj2 = parser.getObj();
|
|
var obj3 = parser.getObj();
|
|
|
|
if (obj1 !== num || obj2 !== gen || !(obj3 instanceof Cmd)) {
|
|
throw new XRefEntryException(`Bad (uncompressed) XRef entry: ${ref}`);
|
|
}
|
|
if (obj3.cmd !== "obj") {
|
|
// some bad PDFs use "obj1234" and really mean 1234
|
|
if (obj3.cmd.startsWith("obj")) {
|
|
num = parseInt(obj3.cmd.substring(3), 10);
|
|
if (!Number.isNaN(num)) {
|
|
return num;
|
|
}
|
|
}
|
|
throw new XRefEntryException(`Bad (uncompressed) XRef entry: ${ref}`);
|
|
}
|
|
if (this.encrypt && !suppressEncryption) {
|
|
xrefEntry = parser.getObj(this.encrypt.createCipherTransform(num, gen));
|
|
} else {
|
|
xrefEntry = parser.getObj();
|
|
}
|
|
if (!isStream(xrefEntry)) {
|
|
if (
|
|
typeof PDFJSDev === "undefined" ||
|
|
PDFJSDev.test("!PRODUCTION || TESTING")
|
|
) {
|
|
assert(
|
|
xrefEntry !== undefined,
|
|
'fetchUncompressed: The "xrefEntry" cannot be undefined.'
|
|
);
|
|
}
|
|
this._cacheMap.set(num, xrefEntry);
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
fetchCompressed(ref, xrefEntry, suppressEncryption = false) {
|
|
const tableOffset = xrefEntry.offset;
|
|
const stream = this.fetch(Ref.get(tableOffset, 0));
|
|
if (!isStream(stream)) {
|
|
throw new FormatError("bad ObjStm stream");
|
|
}
|
|
const first = stream.dict.get("First");
|
|
const n = stream.dict.get("N");
|
|
if (!Number.isInteger(first) || !Number.isInteger(n)) {
|
|
throw new FormatError(
|
|
"invalid first and n parameters for ObjStm stream"
|
|
);
|
|
}
|
|
const parser = new Parser({
|
|
lexer: new Lexer(stream),
|
|
xref: this,
|
|
allowStreams: true,
|
|
});
|
|
const nums = new Array(n);
|
|
// read the object numbers to populate cache
|
|
for (let i = 0; i < n; ++i) {
|
|
const num = parser.getObj();
|
|
if (!Number.isInteger(num)) {
|
|
throw new FormatError(
|
|
`invalid object number in the ObjStm stream: ${num}`
|
|
);
|
|
}
|
|
const offset = parser.getObj();
|
|
if (!Number.isInteger(offset)) {
|
|
throw new FormatError(
|
|
`invalid object offset in the ObjStm stream: ${offset}`
|
|
);
|
|
}
|
|
nums[i] = num;
|
|
}
|
|
const entries = new Array(n);
|
|
// read stream objects for cache
|
|
for (let i = 0; i < n; ++i) {
|
|
const obj = parser.getObj();
|
|
entries[i] = obj;
|
|
// 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 (parser.buf1 instanceof Cmd && parser.buf1.cmd === "endobj") {
|
|
parser.shift();
|
|
}
|
|
if (isStream(obj)) {
|
|
continue;
|
|
}
|
|
const num = nums[i],
|
|
entry = this.entries[num];
|
|
if (entry && entry.offset === tableOffset && entry.gen === i) {
|
|
if (
|
|
typeof PDFJSDev === "undefined" ||
|
|
PDFJSDev.test("!PRODUCTION || TESTING")
|
|
) {
|
|
assert(
|
|
obj !== undefined,
|
|
'fetchCompressed: The "obj" cannot be undefined.'
|
|
);
|
|
}
|
|
this._cacheMap.set(num, obj);
|
|
}
|
|
}
|
|
xrefEntry = entries[xrefEntry.gen];
|
|
if (xrefEntry === undefined) {
|
|
throw new XRefEntryException(`Bad (compressed) XRef entry: ${ref}`);
|
|
}
|
|
return xrefEntry;
|
|
},
|
|
|
|
async fetchIfRefAsync(obj, suppressEncryption) {
|
|
if (obj instanceof Ref) {
|
|
return this.fetchAsync(obj, suppressEncryption);
|
|
}
|
|
return obj;
|
|
},
|
|
|
|
async fetchAsync(ref, suppressEncryption) {
|
|
try {
|
|
return this.fetch(ref, suppressEncryption);
|
|
} catch (ex) {
|
|
if (!(ex instanceof MissingDataException)) {
|
|
throw ex;
|
|
}
|
|
await this.pdfManager.requestRange(ex.begin, ex.end);
|
|
return this.fetchAsync(ref, suppressEncryption);
|
|
}
|
|
},
|
|
|
|
getCatalogObj: function XRef_getCatalogObj() {
|
|
return this.root;
|
|
},
|
|
};
|
|
|
|
return XRef;
|
|
})();
|
|
|
|
/**
|
|
* A NameTree/NumberTree is like a Dict but has some advantageous properties,
|
|
* see the specification (7.9.6 and 7.9.7) for additional details.
|
|
* TODO: implement all the Dict functions and make this more efficient.
|
|
*/
|
|
class NameOrNumberTree {
|
|
constructor(root, xref, type) {
|
|
if (this.constructor === NameOrNumberTree) {
|
|
unreachable("Cannot initialize NameOrNumberTree.");
|
|
}
|
|
this.root = root;
|
|
this.xref = xref;
|
|
this._type = type;
|
|
}
|
|
|
|
getAll() {
|
|
const dict = Object.create(null);
|
|
if (!this.root) {
|
|
return dict;
|
|
}
|
|
const xref = this.xref;
|
|
// Reading Name/Number tree.
|
|
const processed = new RefSet();
|
|
processed.put(this.root);
|
|
const queue = [this.root];
|
|
while (queue.length > 0) {
|
|
const obj = xref.fetchIfRef(queue.shift());
|
|
if (!isDict(obj)) {
|
|
continue;
|
|
}
|
|
if (obj.has("Kids")) {
|
|
const kids = obj.get("Kids");
|
|
for (let i = 0, ii = kids.length; i < ii; i++) {
|
|
const kid = kids[i];
|
|
if (processed.has(kid)) {
|
|
throw new FormatError(`Duplicate entry in "${this._type}" tree.`);
|
|
}
|
|
queue.push(kid);
|
|
processed.put(kid);
|
|
}
|
|
continue;
|
|
}
|
|
const entries = obj.get(this._type);
|
|
if (Array.isArray(entries)) {
|
|
for (let i = 0, ii = entries.length; i < ii; i += 2) {
|
|
dict[xref.fetchIfRef(entries[i])] = xref.fetchIfRef(entries[i + 1]);
|
|
}
|
|
}
|
|
}
|
|
return dict;
|
|
}
|
|
|
|
get(key) {
|
|
if (!this.root) {
|
|
return null;
|
|
}
|
|
const xref = this.xref;
|
|
let kidsOrEntries = xref.fetchIfRef(this.root);
|
|
let loopCount = 0;
|
|
const MAX_LEVELS = 10;
|
|
|
|
// 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 "${this._type}" tree.`);
|
|
return null;
|
|
}
|
|
|
|
const kids = kidsOrEntries.get("Kids");
|
|
if (!Array.isArray(kids)) {
|
|
return null;
|
|
}
|
|
|
|
let l = 0,
|
|
r = kids.length - 1;
|
|
while (l <= r) {
|
|
const m = (l + r) >> 1;
|
|
const kid = xref.fetchIfRef(kids[m]);
|
|
const limits = kid.get("Limits");
|
|
|
|
if (key < xref.fetchIfRef(limits[0])) {
|
|
r = m - 1;
|
|
} else if (key > xref.fetchIfRef(limits[1])) {
|
|
l = m + 1;
|
|
} else {
|
|
kidsOrEntries = xref.fetchIfRef(kids[m]);
|
|
break;
|
|
}
|
|
}
|
|
if (l > r) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// If we get here, then we have found the right entry. Now go through the
|
|
// entries in the dictionary until we find the key we're looking for.
|
|
const entries = kidsOrEntries.get(this._type);
|
|
if (Array.isArray(entries)) {
|
|
// Perform a binary search to reduce the lookup time.
|
|
let l = 0,
|
|
r = entries.length - 2;
|
|
while (l <= r) {
|
|
// Check only even indices (0, 2, 4, ...) because the
|
|
// odd indices contain the actual data.
|
|
const tmp = (l + r) >> 1,
|
|
m = tmp + (tmp & 1);
|
|
const currentKey = xref.fetchIfRef(entries[m]);
|
|
if (key < currentKey) {
|
|
r = m - 2;
|
|
} else if (key > currentKey) {
|
|
l = m + 2;
|
|
} else {
|
|
return xref.fetchIfRef(entries[m + 1]);
|
|
}
|
|
}
|
|
|
|
// Fallback to an exhaustive search, in an attempt to handle corrupt
|
|
// PDF files where keys are not correctly ordered (fixes issue 10272).
|
|
info(
|
|
`Falling back to an exhaustive search, for key "${key}", ` +
|
|
`in "${this._type}" tree.`
|
|
);
|
|
for (let m = 0, mm = entries.length; m < mm; m += 2) {
|
|
const currentKey = xref.fetchIfRef(entries[m]);
|
|
if (currentKey === key) {
|
|
warn(
|
|
`The "${key}" key was found at an incorrect, ` +
|
|
`i.e. out-of-order, position in "${this._type}" tree.`
|
|
);
|
|
return xref.fetchIfRef(entries[m + 1]);
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
}
|
|
|
|
class NameTree extends NameOrNumberTree {
|
|
constructor(root, xref) {
|
|
super(root, xref, "Names");
|
|
}
|
|
}
|
|
|
|
class NumberTree extends NameOrNumberTree {
|
|
constructor(root, xref) {
|
|
super(root, xref, "Nums");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* "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() {
|
|
// eslint-disable-next-line no-shadow
|
|
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 `Dict` 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
|
|
* 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.
|
|
*/
|
|
const ObjectLoader = (function () {
|
|
function mayHaveChildren(value) {
|
|
return (
|
|
value instanceof Ref ||
|
|
value instanceof Dict ||
|
|
Array.isArray(value) ||
|
|
isStream(value)
|
|
);
|
|
}
|
|
|
|
function addChildren(node, nodesToVisit) {
|
|
if (node instanceof Dict) {
|
|
node = node.getRawValues();
|
|
} else if (isStream(node)) {
|
|
node = node.dict.getRawValues();
|
|
} else if (!Array.isArray(node)) {
|
|
return;
|
|
}
|
|
for (const rawValue of node) {
|
|
if (mayHaveChildren(rawValue)) {
|
|
nodesToVisit.push(rawValue);
|
|
}
|
|
}
|
|
}
|
|
|
|
// eslint-disable-next-line no-shadow
|
|
function ObjectLoader(dict, keys, xref) {
|
|
this.dict = dict;
|
|
this.keys = keys;
|
|
this.xref = xref;
|
|
this.refSet = null;
|
|
}
|
|
|
|
ObjectLoader.prototype = {
|
|
async load() {
|
|
// Don't walk the graph if all the data is already loaded; note that only
|
|
// `ChunkedStream` instances have a `allChunksLoaded` method.
|
|
if (
|
|
!this.xref.stream.allChunksLoaded ||
|
|
this.xref.stream.allChunksLoaded()
|
|
) {
|
|
return undefined;
|
|
}
|
|
|
|
const { keys, dict } = this;
|
|
this.refSet = new RefSet();
|
|
// Setup the initial nodes to visit.
|
|
const nodesToVisit = [];
|
|
for (let i = 0, ii = keys.length; i < ii; i++) {
|
|
const rawValue = dict.getRaw(keys[i]);
|
|
// Skip nodes that are guaranteed to be empty.
|
|
if (rawValue !== undefined) {
|
|
nodesToVisit.push(rawValue);
|
|
}
|
|
}
|
|
return this._walk(nodesToVisit);
|
|
},
|
|
|
|
async _walk(nodesToVisit) {
|
|
const nodesToRevisit = [];
|
|
const pendingRequests = [];
|
|
// DFS walk of the object graph.
|
|
while (nodesToVisit.length) {
|
|
let currentNode = nodesToVisit.pop();
|
|
|
|
// Only references or chunked streams can cause missing data exceptions.
|
|
if (currentNode instanceof Ref) {
|
|
// Skip nodes that have already been visited.
|
|
if (this.refSet.has(currentNode)) {
|
|
continue;
|
|
}
|
|
try {
|
|
this.refSet.put(currentNode);
|
|
currentNode = this.xref.fetch(currentNode);
|
|
} catch (ex) {
|
|
if (!(ex instanceof MissingDataException)) {
|
|
throw ex;
|
|
}
|
|
nodesToRevisit.push(currentNode);
|
|
pendingRequests.push({ begin: ex.begin, end: ex.end });
|
|
}
|
|
}
|
|
if (currentNode && currentNode.getBaseStreams) {
|
|
const baseStreams = currentNode.getBaseStreams();
|
|
let foundMissingData = false;
|
|
for (let i = 0, ii = baseStreams.length; i < ii; i++) {
|
|
const stream = baseStreams[i];
|
|
if (stream.allChunksLoaded && !stream.allChunksLoaded()) {
|
|
foundMissingData = true;
|
|
pendingRequests.push({ begin: stream.start, end: stream.end });
|
|
}
|
|
}
|
|
if (foundMissingData) {
|
|
nodesToRevisit.push(currentNode);
|
|
}
|
|
}
|
|
|
|
addChildren(currentNode, nodesToVisit);
|
|
}
|
|
|
|
if (pendingRequests.length) {
|
|
await this.xref.stream.manager.requestRanges(pendingRequests);
|
|
|
|
for (let i = 0, ii = nodesToRevisit.length; i < ii; i++) {
|
|
const node = nodesToRevisit[i];
|
|
// Remove any reference nodes from the current `RefSet` so they
|
|
// aren't skipped when we revist them.
|
|
if (node instanceof Ref) {
|
|
this.refSet.remove(node);
|
|
}
|
|
}
|
|
return this._walk(nodesToRevisit);
|
|
}
|
|
// Everything is loaded.
|
|
this.refSet = null;
|
|
return undefined;
|
|
},
|
|
};
|
|
|
|
return ObjectLoader;
|
|
})();
|
|
|
|
export { Catalog, FileSpec, ObjectLoader, XRef };
|