public StreamEncryptionInfo(RecordInputStream rs, List<Record> outputRecs) {
Record rec;
rs.nextRecord();
int recSize = 4 + rs.remaining();
rec = RecordFactory.createSingleRecord(rs);
outputRecs.add(rec);
FilePassRecord fpr = null;
if (rec instanceof BOFRecord) {
_hasBOFRecord = true;
// Fetch the next record, and see if it indicates whether
// the document is encrypted or not
if (rs.hasNextRecord()) {
rs.nextRecord();
rec = RecordFactory.createSingleRecord(rs);
recSize += rec.getRecordSize();
outputRecs.add(rec);
// Encrypted is normally BOF then FILEPASS
// May sometimes be BOF, WRITEPROTECT, FILEPASS
if (rec instanceof WriteProtectRecord && rs.hasNextRecord()) {
rs.nextRecord();
rec = RecordFactory.createSingleRecord(rs);
recSize += rec.getRecordSize();
outputRecs.add(rec);
}
// If it's a FILEPASS, track it specifically but
// don't include it in the main stream
if (rec instanceof FilePassRecord) {
fpr = (FilePassRecord) rec;
outputRecs.remove(outputRecs.size() - 1);
// TODO - add fpr not added to outputRecs
rec = outputRecs.get(0);
} else {
// workbook not encrypted (typical case)
if (rec instanceof EOFRecord) {
// A workbook stream is never empty, so crash instead
// of trying to keep track of nesting level
throw new IllegalStateException("Nothing between BOF and EOF");
}
}
}
} else {
// Invalid in a normal workbook stream.
// However, some test cases work on sub-sections of
// the workbook stream that do not begin with BOF
_hasBOFRecord = false;
}
_initialRecordsSize = recSize;
_filePassRec = fpr;
_lastRecord = rec;
}
/**
* @return the next available record, or <code>null</code> if this pass didn't return a record
* that's suitable for returning (eg was a continue record).
*/
private Record readNextRecord() {
Record record = RecordFactory.createSingleRecord(_recStream);
_lastRecordWasEOFLevelZero = false;
if (record instanceof BOFRecord) {
_bofDepth++;
return record;
}
if (record instanceof EOFRecord) {
_bofDepth--;
if (_bofDepth < 1) {
_lastRecordWasEOFLevelZero = true;
}
return record;
}
if (record instanceof DBCellRecord) {
// Not needed by POI. Regenerated from scratch by POI when spreadsheet is written
return null;
}
if (record instanceof RKRecord) {
return RecordFactory.convertToNumberRecord((RKRecord) record);
}
if (record instanceof MulRKRecord) {
Record[] records = RecordFactory.convertRKRecords((MulRKRecord) record);
_unreadRecordBuffer = records;
_unreadRecordIndex = 1;
return records[0];
}
if (record.getSid() == DrawingGroupRecord.sid && _lastRecord instanceof DrawingGroupRecord) {
DrawingGroupRecord lastDGRecord = (DrawingGroupRecord) _lastRecord;
lastDGRecord.join((AbstractEscherHolderRecord) record);
return null;
}
if (record.getSid() == ContinueRecord.sid) {
ContinueRecord contRec = (ContinueRecord) record;
if (_lastRecord instanceof ObjRecord || _lastRecord instanceof TextObjectRecord) {
// Drawing records have a very strange continue behaviour.
// There can actually be OBJ records mixed between the continues.
_lastDrawingRecord.processContinueRecord(contRec.getData());
// we must remember the position of the continue record.
// in the serialization procedure the original structure of records must be preserved
if (_shouldIncludeContinueRecords) {
return record;
}
return null;
}
if (_lastRecord instanceof DrawingGroupRecord) {
((DrawingGroupRecord) _lastRecord).processContinueRecord(contRec.getData());
return null;
}
if (_lastRecord instanceof DrawingRecord) {
// ((DrawingRecord) _lastRecord).appendContinueRecord(contRec.getData());
return contRec;
}
if (_lastRecord instanceof UnknownRecord) {
// Gracefully handle records that we don't know about,
// that happen to be continued
return record;
}
if (_lastRecord instanceof EOFRecord) {
// This is really odd, but excel still sometimes
// outputs a file like this all the same
return record;
}
throw new RecordFormatException(
"Unhandled Continue Record followining " + _lastRecord.getClass());
}
_lastRecord = record;
if (record instanceof DrawingRecord) {
_lastDrawingRecord = (DrawingRecord) record;
}
return record;
}
