/// <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();
}
}
}
/// <summary>
/// Initializes a new PDFReference instance from the specified object identifier and file position.
/// </summary>
public PDFReference(PDFObjectID objectID, int position)
{
_objectID = objectID;
Position = position;
#if UNIQUE_IREF && DEBUG
_uid = ++s_counter;
#endif
}
/// <summary>
/// Opens an existing PDF document.
/// </summary>
public static PDFDocument Open(Stream stream, string password, PDFDocumentOpenMode openmode, PDFPasswordProvider passwordProvider)
{
PDFDocument document;
try
{
Lexer lexer = new Lexer(stream);
document = new PDFDocument(lexer);
document.State |= DocumentState.Imported;
document.OpenMode = openmode;
document.FileSize = stream.Length;
// Get file version.
byte[] header = new byte[1024];
stream.Position = 0;
stream.Read(header, 0, 1024);
document._version = GetPDFFileVersion(header);
if (document._version == 0)
{
throw new InvalidOperationException(PSSR.InvalidPDF);
}
document.IrefTable.IsUnderConstruction = true;
Parser parser = new Parser(document);
// Read all trailers or cross-reference streams, but no objects.
document.Trailer = parser.ReadTrailer();
if (document.Trailer == null)
{
ParserDiagnostics.ThrowParserException("Invalid PDF file: no trailer found."); // TODO L10N using PSSR.
}
Debug.Assert(document.IrefTable.IsUnderConstruction);
document.IrefTable.IsUnderConstruction = false;
// Is document encrypted?
PDFReference xrefEncrypt = document.Trailer.Elements[PDFTrailer.Keys.Encrypt] as PDFReference;
if (xrefEncrypt != null)
{
//xrefEncrypt.Value = parser.ReadObject(null, xrefEncrypt.ObjectID, false);
PDFObject encrypt = parser.ReadObject(null, xrefEncrypt.ObjectID, false, false);
encrypt.Reference = xrefEncrypt;
xrefEncrypt.Value = encrypt;
PDFStandardSecurityHandler securityHandler = document.SecurityHandler;
TryAgain:
PasswordValidity validity = securityHandler.ValidatePassword(password);
if (validity == PasswordValidity.Invalid)
{
if (passwordProvider != null)
{
PDFPasswordProviderArgs args = new PDFPasswordProviderArgs();
passwordProvider(args);
if (args.Abort)
{
return(null);
}
password = args.Password;
goto TryAgain;
}
else
{
if (password == null)
{
throw new PDFReaderException(PSSR.PasswordRequired);
}
else
{
throw new PDFReaderException(PSSR.InvalidPassword);
}
}
}
else if (validity == PasswordValidity.UserPassword && openmode == PDFDocumentOpenMode.Modify)
{
if (passwordProvider != null)
{
PDFPasswordProviderArgs args = new PDFPasswordProviderArgs();
passwordProvider(args);
if (args.Abort)
{
return(null);
}
password = args.Password;
goto TryAgain;
}
else
{
throw new PDFReaderException(PSSR.OwnerPasswordRequired);
}
}
}
else
{
if (password != null)
{
// Password specified but document is not encrypted.
// ignore
}
}
PDFReference[] irefs2 = document.IrefTable.AllReferences;
int count2 = irefs2.Length;
// 3rd: Create iRefs for all compressed objects.
Dictionary <int, object> objectStreams = new Dictionary <int, object>();
for (int idx = 0; idx < count2; idx++)
{
PDFReference iref = irefs2[idx];
if (iref.Value is PDFCrossReferenceStream xrefStream)
{
for (int idx2 = 0; idx2 < xrefStream.Entries.Count; idx2++)
{
PDFCrossReferenceStream.CrossReferenceStreamEntry item = xrefStream.Entries[idx2];
// Is type xref to compressed object?
if (item.Type == 2)
{
//PDFReference irefNew = parser.ReadCompressedObject(new PDFObjectID((int)item.Field2), (int)item.Field3);
//document._irefTable.Add(irefNew);
int objectNumber = (int)item.Field2;
if (!objectStreams.ContainsKey(objectNumber))
{
objectStreams.Add(objectNumber, null);
PDFObjectID objectID = new PDFObjectID((int)item.Field2);
parser.ReadIRefsFromCompressedObject(objectID);
}
}
}
}
}
// 4th: Read compressed objects.
for (int idx = 0; idx < count2; idx++)
{
PDFReference iref = irefs2[idx];
if (iref.Value is PDFCrossReferenceStream xrefStream)
{
for (int idx2 = 0; idx2 < xrefStream.Entries.Count; idx2++)
{
PDFCrossReferenceStream.CrossReferenceStreamEntry item = xrefStream.Entries[idx2];
// Is type xref to compressed object?
if (item.Type == 2)
{
PDFReference irefNew = parser.ReadCompressedObject(new PDFObjectID((int)item.Field2),
(int)item.Field3);
Debug.Assert(document.IrefTable.Contains(iref.ObjectID));
//document._irefTable.Add(irefNew);
}
}
}
}
PDFReference[] irefs = document.IrefTable.AllReferences;
int count = irefs.Length;
// Read all indirect objects.
for (int idx = 0; idx < count; idx++)
{
PDFReference iref = irefs[idx];
if (iref.Value == null)
{
#if DEBUG_
if (iref.ObjectNumber == 1074)
{
iref.GetType();
}
#endif
try
{
Debug.Assert(document.IrefTable.Contains(iref.ObjectID));
PDFObject pdfObject = parser.ReadObject(null, iref.ObjectID, false, false);
Debug.Assert(pdfObject.Reference == iref);
pdfObject.Reference = iref;
Debug.Assert(pdfObject.Reference.Value != null, "Something went wrong.");
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
// 4STLA rethrow exception to notify caller.
throw;
}
}
else
{
Debug.Assert(document.IrefTable.Contains(iref.ObjectID));
//iref.GetType();
}
// Set maximum object number.
document.IrefTable._maxObjectNumber = Math.Max(document.IrefTable._maxObjectNumber,
iref.ObjectNumber);
}
// Encrypt all objects.
if (xrefEncrypt != null)
{
document.SecurityHandler.EncryptDocument();
}
// Fix references of trailer values and then objects and irefs are consistent.
document.Trailer.Finish();
#if DEBUG_
// Some tests...
PDFReference[] reachables = document.xrefTable.TransitiveClosure(document.trailer);
reachables.GetType();
reachables = document.xrefTable.AllXRefs;
document.xrefTable.CheckConsistence();
#endif
if (openmode == PDFDocumentOpenMode.Modify)
{
// Create new or change existing document IDs.
if (document.Internals.SecondDocumentID == "")
{
document.Trailer.CreateNewDocumentIDs();
}
else
{
byte[] agTemp = Guid.NewGuid().ToByteArray();
document.Internals.SecondDocumentID = PDFEncoders.RawEncoding.GetString(agTemp, 0, agTemp.Length);
}
// Change modification date
document.Info.ModificationDate = DateTime.Now;
// Remove all unreachable objects
int removed = document.IrefTable.Compact();
if (removed != 0)
{
Debug.WriteLine("Number of deleted unreachable objects: " + removed);
}
// Force flattening of page tree
PDFPages pages = document.Pages;
Debug.Assert(pages != null);
//bool b = document.irefTable.Contains(new PDFObjectID(1108));
//b.GetType();
document.IrefTable.CheckConsistence();
document.IrefTable.Renumber();
document.IrefTable.CheckConsistence();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
throw;
}
return(document);
}
/// <summary> /// Gets the cloned object that corresponds to the specified external identifier. /// </summary> public PDFReference this[PDFObjectID externalID] => _externalIDs[externalID.ToString()];
/// <summary> /// Adds a cloned object to this table. /// </summary> /// <param name="externalID">The object identifier in the foreign object.</param> /// <param name="iref">The cross reference to the clone of the foreign object, which belongs to /// this document. In general the clone has a different object identifier.</param> public void Add(PDFObjectID externalID, PDFReference iref) => _externalIDs[externalID.ToString()] = iref;
/// <summary> /// Indicates whether the specified object is already imported. /// </summary> public bool Contains(PDFObjectID externalID) => _externalIDs.ContainsKey(externalID.ToString());