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;
}
/** Returns the next (complete) record from the stream, or null if there are no more. */
public Record nextRecord() {
Record r;
r = getNextUnreadRecord();
if (r != null) {
// found an unread record
return r;
}
while (true) {
if (!_recStream.hasNextRecord()) {
// recStream is exhausted;
return null;
}
if (_lastRecordWasEOFLevelZero) {
// Potential place for ending the workbook stream
// Check that the next record is not BOFRecord(0x0809)
// Normally the input stream contains only zero padding after the last EOFRecord,
// but bug 46987 and 48068 suggests that the padding may be garbage.
// This code relies on the padding bytes not starting with BOFRecord.sid
if (_recStream.getNextSid() != BOFRecord.sid) {
return null;
}
// else - another sheet substream starting here
}
// step underlying RecordInputStream to the next record
_recStream.nextRecord();
r = readNextRecord();
if (r == null) {
// some record types may get skipped (e.g. DBCellRecord and ContinueRecord)
continue;
}
return r;
}
}
