/// <summary>
/// Appends current character to the token and reads next one.
/// </summary>
internal char AppendAndScanNextChar()
{
if (_currChar == Chars.EOF)
{
ParserDiagnostics.ThrowParserException("Undetected EOF reached.");
}
_token.Append(_currChar);
return(ScanNextChar(true));
}
/// <summary>
/// Scans a number.
/// </summary>
public Symbol ScanNumber()
{
// I found a PDF file created with Acrobat 7 with this entry
// /Checksum 2996984786
// What is this? It is neither an integer nor a real.
// I introduced an UInteger...
bool period = false;
//bool sign;
_token = new StringBuilder();
char ch = _currChar;
if (ch == '+' || ch == '-')
{
//sign = true;
_token.Append(ch);
ch = ScanNextChar(true);
}
while (true)
{
if (char.IsDigit(ch))
{
_token.Append(ch);
}
else if (ch == '.')
{
if (period)
{
ParserDiagnostics.ThrowParserException("More than one period in number.");
}
period = true;
_token.Append(ch);
}
else
{
break;
}
ch = ScanNextChar(true);
}
if (period)
{
return(Symbol.Real);
}
long l = Int64.Parse(_token.ToString(), CultureInfo.InvariantCulture);
if (l >= Int32.MinValue && l <= Int32.MaxValue)
{
return(Symbol.Integer);
}
if (l > 0 && l <= UInt32.MaxValue)
{
return(Symbol.UInteger);
}
// Got an AutoCAD PDF file that contains this: /C 264584027963392
// Best we can do is to convert it to real value.
return(Symbol.Real);
//thr ow new PdfReaderException("Number exceeds integer range.");
}
/// <summary>
/// Opens an existing PDF document asynchronously.
/// </summary>
public static async Task <PdfDocument> OpenAsync(
Stream stream,
string password = null,
PdfDocumentOpenMode openmode = PdfDocumentOpenMode.Modify,
PdfPasswordProvider passwordProvider = null)
{
PdfDocument document;
#if !DEBUG
try
#endif
{
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 = await parser.ReadTrailerAsync();
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)
{
PdfObject encrypt = await parser.ReadObjectAsync(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 = await parser.ReadObjectAsync(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);
}
// Decrypt all objects.
if (xrefEncrypt != null)
{
document.SecurityHandler.DecryptDocument();
}
// 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();
}
}
#if !DEBUG
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
throw;
}
#endif
return(document);
}