public IReadOnlyList <CosObject> Parse(PdfRawStream stream, CosObjectPool pool)
{
if (stream == null)
{
throw new ArgumentNullException(nameof(stream));
}
//need to first parse the header.
var numberOfObjects = stream.Dictionary.GetIntOrDefault(CosName.N);
var objectNumbers = new List <long>(numberOfObjects);
var streamObjects = new List <CosObject>(numberOfObjects);
var bytes = stream.Decode(filterProvider);
var reader = new RandomAccessBuffer(bytes);
for (int i = 0; i < numberOfObjects; i++)
{
long objectNumber = ObjectHelper.ReadObjectNumber(reader);
// skip offset
ReadHelper.ReadLong(reader);
objectNumbers.Add(objectNumber);
}
CosObject obj;
CosBase cosObject;
int objectCounter = 0;
while ((cosObject = baseParser.Parse(reader, pool)) != null)
{
obj = new CosObject(cosObject);
obj.SetGenerationNumber(0);
if (objectCounter >= objectNumbers.Count)
{
log.Error("/ObjStm (object stream) has more objects than /N " + numberOfObjects);
break;
}
obj.SetObjectNumber(objectNumbers[objectCounter]);
streamObjects.Add(obj);
// According to the spec objects within an object stream shall not be enclosed
// by obj/endobj tags, but there are some pdfs in the wild using those tags
// skip endobject marker if present
if (!reader.IsEof() && reader.Peek() == 'e')
{
ReadHelper.ReadLine(reader);
}
objectCounter++;
}
return(streamObjects);
}
private CosBase ParseObjectFromFile(long offset, IRandomAccessRead reader,
CosObjectKey key,
CosObjectPool pool,
bool isLenientParsing)
{
reader.Seek(offset);
var objectNumber = ObjectHelper.ReadObjectNumber(reader);
var objectGeneration = ObjectHelper.ReadGenerationNumber(reader);
ReadHelper.ReadExpectedString(reader, "obj", true);
if (objectNumber != key.Number || objectGeneration != key.Generation)
{
throw new InvalidOperationException($"Xref for {key} points to object {objectNumber} {objectGeneration} at {offset}");
}
ReadHelper.SkipSpaces(reader);
var baseObject = baseParser.Parse(reader, pool);
var endObjectKey = ReadHelper.ReadString(reader);
var atStreamStart = string.Equals(endObjectKey, "stream");
if (atStreamStart)
{
var streamStartBytes = OtherEncodings.StringAsLatin1Bytes(endObjectKey);
reader.Rewind(streamStartBytes.Length);
baseObject = ReadNormalObjectStream(reader, baseObject, offset, isLenientParsing, out endObjectKey);
}
if (!string.Equals(endObjectKey, "endobj"))
{
var message =
$"Object ({objectNumber}:{objectGeneration}) at offset {offset} does not end with \'endobj\' but with \'{endObjectKey}\'";
if (isLenientParsing)
{
log.Warn(message);
}
else
{
throw new InvalidOperationException(message);
}
}
return(baseObject);
}