Exemplo n.º 1
0
        /// <summary>
        /// Reads the compressed object with the specified index.
        /// </summary>
        internal void ReadReferences(PdfCrossReferenceTable xrefTable)
        {
            ////// Create parser for stream.
            ////Parser parser = new Parser(_document, new MemoryStream(Stream.Value));
            for (int idx = 0; idx < _header.Length; idx++)
            {
                int objectNumber = _header[idx][0];
                int offset = _header[idx][1];

                PdfObjectID objectID = new PdfObjectID(objectNumber);

                // HACK: -1 indicates compressed object.
                PdfReference iref = new PdfReference(objectID, -1);
                ////iref.ObjectID = objectID;
                ////iref.Value = xrefStream;
                if (!xrefTable.Contains(iref.ObjectID))
                {
                    xrefTable.Add(iref);
                }
                else
                {
                    GetType();
                }
            }
        }
Exemplo n.º 2
0
        /// <summary>
        /// Reads the compressed object with the specified index.
        /// </summary>
        internal void ReadReferences(PdfCrossReferenceTable xrefTable)
        {
            ////// Create parser for stream.
            ////Parser parser = new Parser(_document, new MemoryStream(Stream.Value));
            for (int idx = 0; idx < _header.Length; idx++)
            {
                int objectNumber = _header[idx][0];
                int offset       = _header[idx][1];

                PdfObjectID objectID = new PdfObjectID(objectNumber);

                // HACK: -1 indicates compressed object.
                PdfReference iref = new PdfReference(objectID, -1);
                ////iref.ObjectID = objectID;
                ////iref.Value = xrefStream;
                if (!xrefTable.Contains(iref.ObjectID))
                {
                    xrefTable.Add(iref);
                }
                else
                {
                    GetType();
                }
            }
        }
Exemplo n.º 3
0
        /// <summary>
        /// Constructs the PdfTrailer from a document.
        /// </summary>
        /// <param name="parser">the parser used to read the file.</param>
        internal void ConstructFromDocument(Parser parser)
        {
            // TODO - May need to also search for encryption related trailer info
            PdfCrossReferenceTable xrefTable = _document._irefTable;

            Elements.SetInteger(Keys.Size, xrefTable.ObjectTable.Count);

            // find the root.
            PdfDictionary rootToUse = null;

            foreach (var reference in xrefTable.AllReferences)
            {
                PdfObject obj = parser.ReadObject(null, reference.ObjectID, false, false);
                if (obj is PdfDictionary dObj)
                {
                    if (dObj.Elements[PdfCatalog.Keys.Type] as PdfName == "/Catalog")
                    {
                        if (rootToUse == null)
                        {
                            rootToUse = dObj;
                        }
                        else if (dObj.ObjectID.GenerationNumber > rootToUse.ObjectID.GenerationNumber)
                        {
                            rootToUse = dObj;
                        }
                    }
                }
            }

            if (rootToUse != null)
            {
                Elements.SetReference(Keys.Root, rootToUse);
            }
        }
Exemplo n.º 4
0
        /// <summary>
        /// Reads cross reference stream(s).
        /// </summary>
        private PdfTrailer ReadXRefStream(PdfCrossReferenceTable xrefTable)
        {
            // Read cross reference stream.
            //Debug.Assert(_lexer.Symbol == Symbol.Integer);

            int number = _lexer.TokenToInteger;
            int generation = ReadInteger();
            Debug.Assert(generation == 0);

            ReadSymbol(Symbol.Obj);
            ReadSymbol(Symbol.BeginDictionary);
            PdfObjectID objectID = new PdfObjectID(number, generation);

            PdfCrossReferenceStream xrefStream = new PdfCrossReferenceStream(_document);

            ReadDictionary(xrefStream, false);
            ReadSymbol(Symbol.BeginStream);
            ReadStream(xrefStream);

            //xrefTable.Add(new PdfReference(objectID, position));
            PdfReference iref = new PdfReference(xrefStream);
            iref.ObjectID = objectID;
            iref.Value = xrefStream;
            xrefTable.Add(iref);

            Debug.Assert(xrefStream.Stream != null);
            //string sValue = new RawEncoding().GetString(xrefStream.Stream.UnfilteredValue,);
            //sValue.GetType();
            byte[] bytesRaw = xrefStream.Stream.UnfilteredValue;
            byte[] bytes = bytesRaw;

            // HACK: Should be done in UnfilteredValue.
            if (xrefStream.Stream.HasDecodeParams)
            {
                int predictor = xrefStream.Stream.DecodePredictor;
                int columns = xrefStream.Stream.DecodeColumns;
                bytes = DecodeCrossReferenceStream(bytesRaw, columns, predictor);
            }

#if DEBUG_
            for (int idx = 0; idx < bytes.Length; idx++)
            {
                if (idx % 4 == 0)
                    Console.WriteLine();
                Console.Write("{0:000} ", (int)bytes[idx]);
            }
            Console.WriteLine();
#endif

            //     bytes.GetType();
            // Add to table.
            //    xrefTable.Add(new PdfReference(objectID, -1));

            int size = xrefStream.Elements.GetInteger(PdfCrossReferenceStream.Keys.Size);
            PdfArray index = xrefStream.Elements.GetValue(PdfCrossReferenceStream.Keys.Index) as PdfArray;
            int prev = xrefStream.Elements.GetInteger(PdfCrossReferenceStream.Keys.Prev);
            PdfArray w = (PdfArray)xrefStream.Elements.GetValue(PdfCrossReferenceStream.Keys.W);

            // E.g.: W[1 2 1] ¤ Index[7 12] ¤ Size 19

            // Setup subsections.
            int subsectionCount;
            int[][] subsections = null;
            int subsectionEntryCount = 0;
            if (index == null)
            {
                // Setup with default values.
                subsectionCount = 1;
                subsections = new int[subsectionCount][];
                subsections[0] = new int[] { 0, size }; // HACK: What is size? Contratiction in PDF reference.
                subsectionEntryCount = size;
            }
            else
            {
                // Read subsections from array.
                Debug.Assert(index.Elements.Count % 2 == 0);
                subsectionCount = index.Elements.Count / 2;
                subsections = new int[subsectionCount][];
                for (int idx = 0; idx < subsectionCount; idx++)
                {
                    subsections[idx] = new int[] { index.Elements.GetInteger(2 * idx), index.Elements.GetInteger(2 * idx + 1) };
                    subsectionEntryCount += subsections[idx][1];
                }
            }

            // W key.
            Debug.Assert(w.Elements.Count == 3);
            int[] wsize = { w.Elements.GetInteger(0), w.Elements.GetInteger(1), w.Elements.GetInteger(2) };
            int wsum = StreamHelper.WSize(wsize);
            if (wsum * subsectionEntryCount != bytes.Length)
                GetType();
            Debug.Assert(wsum * subsectionEntryCount == bytes.Length, "Check implementation here.");
            int testcount = subsections[0][1];
            int[] currentSubsection = subsections[0];
#if DEBUG && CORE
            if (PdfDiagnostics.TraceXrefStreams)
            {
                for (int idx = 0; idx < testcount; idx++)
                {
                    uint field1 = StreamHelper.ReadBytes(bytes, idx * wsum, wsize[0]);
                    uint field2 = StreamHelper.ReadBytes(bytes, idx * wsum + wsize[0], wsize[1]);
                    uint field3 = StreamHelper.ReadBytes(bytes, idx * wsum + wsize[0] + wsize[1], wsize[2]);
                    string res = String.Format("{0,2:00}: {1} {2,5} {3}  // ", idx, field1, field2, field3);
                    switch (field1)
                    {
                        case 0:
                            res += "Fee list: object number, generation number";
                            break;

                        case 1:
                            res += "Not compresed: offset, generation number";
                            break;

                        case 2:
                            res += "Compressed: object stream object number, index in stream";
                            break;

                        default:
                            res += "??? Type undefined";
                            break;
                    }
                    Debug.WriteLine(res);
                }
            }
#endif

            int index2 = -1;
            for (int ssc = 0; ssc < subsectionCount; ssc++)
            {
                int abc = subsections[ssc][1];
                for (int idx = 0; idx < abc; idx++)
                {
                    index2++;

                    PdfCrossReferenceStream.CrossReferenceStreamEntry item =
                        new PdfCrossReferenceStream.CrossReferenceStreamEntry();

                    item.Type = StreamHelper.ReadBytes(bytes, index2 * wsum, wsize[0]);
                    item.Field2 = StreamHelper.ReadBytes(bytes, index2 * wsum + wsize[0], wsize[1]);
                    item.Field3 = StreamHelper.ReadBytes(bytes, index2 * wsum + wsize[0] + wsize[1], wsize[2]);

                    xrefStream.Entries.Add(item);

                    switch (item.Type)
                    {
                        case 0:
                            // Nothing to do, not needed.
                            break;

                        case 1: // offset / generation number
                            //// Even it is restricted, an object can exists in more than one subsection.
                            //// (PDF Reference Implementation Notes 15).

                            int position = (int)item.Field2;
                            objectID = ReadObjectNumber(position);
#if DEBUG
                            if (objectID.ObjectNumber == 1074)
                                GetType();
#endif
                            Debug.Assert(objectID.GenerationNumber == item.Field3);

                            //// Ignore the latter one.
                            if (!xrefTable.Contains(objectID))
                            {
#if DEBUG
                                GetType();
#endif
                                // Add iref for all uncrompressed objects.
                                xrefTable.Add(new PdfReference(objectID, position));

                            }
                            break;

                        case 2:
                            // Nothing to do yet.
                            break;
                    }
                }
            }
            return xrefStream;
        }
Exemplo n.º 5
0
        /// <summary>
        /// Reads cross reference table(s) and trailer(s).
        /// </summary>
        private PdfTrailer ReadXRefTableAndTrailer(PdfCrossReferenceTable xrefTable)
        {
            Debug.Assert(xrefTable != null);

            Symbol symbol = ScanNextToken();

            if (symbol == Symbol.XRef)  // Is it a cross-reference table?
            {
                // Reference: 3.4.3  Cross-Reference Table / Page 93
                while (true)
                {
                    symbol = ScanNextToken();
                    if (symbol == Symbol.Integer)
                    {
                        int start = _lexer.TokenToInteger;
                        int length = ReadInteger();
                        for (int id = start; id < start + length; id++)
                        {
                            int position = ReadInteger();
                            int generation = ReadInteger();
                            ReadSymbol(Symbol.Keyword);
                            string token = _lexer.Token;
                            // Skip start entry
                            if (id == 0)
                                continue;
                            // Skip unused entries.
                            if (token != "n")
                                continue;
                            // Even it is restricted, an object can exists in more than one subsection.
                            // (PDF Reference Implementation Notes 15).
                            PdfObjectID objectID = new PdfObjectID(id, generation);
                            // Ignore the latter one.
                            if (xrefTable.Contains(objectID))
                                continue;
                            xrefTable.Add(new PdfReference(objectID, position));
                        }
                    }
                    else if (symbol == Symbol.Trailer)
                    {
                        ReadSymbol(Symbol.BeginDictionary);
                        PdfTrailer trailer = new PdfTrailer(_document);
                        ReadDictionary(trailer, false);
                        return trailer;
                    }
                    else
                        ParserDiagnostics.HandleUnexpectedToken(_lexer.Token);
                }
            }
            // ReSharper disable once RedundantIfElseBlock because of code readability.
            else if (symbol == Symbol.Integer) // Is it an cross-reference stream?
            {
                // Reference: 3.4.7  Cross-Reference Streams / Page 93
                // TODO: Handle PDF files larger than 2 GiB, see implementation note 21 in Appendix H.

                // The parsed integer is the object id of the cross-refernece stream.
                return ReadXRefStream(xrefTable);
            }
            return null;
        }
Exemplo n.º 6
0
 void Initialize()
 {
     //_info = new PdfInfo(this);
     _fontTable = new PdfFontTable(this);
     _imageTable = new PdfImageTable(this);
     _trailer = new PdfTrailer(this);
     _irefTable = new PdfCrossReferenceTable(this);
     _trailer.CreateNewDocumentIDs();
 }
Exemplo n.º 7
0
        internal PdfDocument(Lexer lexer)
        {
            //PdfDocument.Gob.AttatchDocument(Handle);

            _creation = DateTime.Now;
            _state = DocumentState.Imported;

            //_info = new PdfInfo(this);
            //_pages = new PdfPages(this);
            //_fontTable = new PdfFontTable();
            //_catalog = new PdfCatalog(this);
            ////_font = new PdfFont();
            //_objects = new PdfObjectTable(this);
            //_trailer = new PdfTrailer(this);
            _irefTable = new PdfCrossReferenceTable(this);
            _lexer = lexer;
        }