private void read(Stream fis, ISasReaderCallback callback)
{
SasHeader header = readHeader(fis);
//Logger.Info(string.Format("Header: {0}", header));
readPages(fis, header, callback);
//Logger.Info("Done!");
}
public void read(ISasReaderCallback callback)
{
if (_stream != null)
{
read(_stream, callback);
}
else
{
using (FileStream fis = new FileStream(_file.PathName, FileMode.Open, FileAccess.Read))
{
read(fis, callback);
}
}
}
private void readPages(Stream fis, SasHeader header, ISasReaderCallback callback)
{
List <SasSubHeader> subHeaders = new List <SasSubHeader>();
List <int> columnOffsets = new List <int>();
List <int> columnLengths = new List <int>();
List <SasColumnType> columnTypes = new List <SasColumnType>();
bool subHeadersParsed = false;
int rowCount = 0;
int pageSize = header.getPageSize();
int pageCount = header.getPageCount();
// these variables will define the default amount of rows per page and
// other defaults
int row_count = -1;
int row_count_fp = -1;
int row_length = -1;
int col_count = -1;
for (int pageNumber = 0; pageNumber < pageCount; pageNumber++)
{
//Logger.Info(string.Format("Reading page no. {0}", pageNumber));
byte[] pageData = new byte[pageSize];
int read = fis.Read(pageData, 0, pageSize);
if (read == -1)
{
// reached end of file
break;
}
byte pageType = IO.readByte(pageData, 17);
switch (pageType)
{
case 0:
case 1:
case 2:
// accepted type
//Logger.Info(string.Format("Page type supported: {0}", pageType));
break;
case 4:
// accepted but not supported
//Logger.Info(string.Format("Page type not fully supported: {0}", pageType));
break;
default:
throw new Exception("Page " + pageNumber + " has unknown type: " + pageType);
}
if (pageType == 0 || pageType == 2)
{
// Read subheaders
int subhCount = IO.readInt(pageData, 20);
for (int subHeaderNumber = 0; subHeaderNumber < subhCount; subHeaderNumber++)
{
int _base = 24 + subHeaderNumber * 12;
int offset = IO.readInt(pageData, _base);
int length = IO.readInt(pageData, _base + 4);
if (length > 0)
{
byte[] rawData = IO.readBytes(pageData, offset, length);
byte[] signatureData = IO.readBytes(rawData, 0, 4);
SasSubHeader subHeader = new SasSubHeader(rawData,
signatureData);
subHeaders.Add(subHeader);
}
}
}
if ((pageType == 1 || pageType == 2))
{
if (!subHeadersParsed)
{
// Parse subheaders
SasSubHeader rowSize = getSubHeader(subHeaders,
SUBH_ROWSIZE, "ROWSIZE");
row_length = IO.readInt(rowSize.getRawData(), 20);
row_count = IO.readInt(rowSize.getRawData(), 24);
int col_count_7 = IO.readInt(rowSize.getRawData(), 36);
row_count_fp = IO.readInt(rowSize.getRawData(), 60);
SasSubHeader colSize = getSubHeader(subHeaders,
SUBH_COLSIZE, "COLSIZE");
int col_count_6 = IO.readInt(colSize.getRawData(), 4);
col_count = col_count_6;
//if (col_count_7 != col_count_6) {
// Logger.Warn(
// string.Format("({0}) Column count mismatch: {1} vs. {2}",
// _file.PathName, col_count_6, col_count_7 ));
//}
SasSubHeader colText = getSubHeader(subHeaders,
SUBH_COLTEXT, "COLTEXT");
List <SasSubHeader> colAttrHeaders = getSubHeaders(
subHeaders, SUBH_COLATTR, "COLATTR");
SasSubHeader colAttr;
if (!colAttrHeaders.Any())
{
throw new Exception(
"No column attribute subheader found");
}
else if (colAttrHeaders.Count == 1)
{
colAttr = colAttrHeaders[0];
}
else
{
colAttr = spliceColAttrSubHeaders(colAttrHeaders);
}
SasSubHeader colName = getSubHeader(subHeaders,
SUBH_COLNAME, "COLNAME");
List <SasSubHeader> colLabels = getSubHeaders(subHeaders,
SUBH_COLLABS, "COLLABS");
if (colLabels.Any() && colLabels.Count != col_count)
{
throw new Exception(
"Unexpected column label count ("
+ colLabels.Count + ") expected 0 or "
+ col_count);
}
for (int i = 0; i < col_count; i++)
{
int _base = 12 + i * 8;
String columnName;
byte amd = IO.readByte(colName.getRawData(), _base);
if (amd == 0)
{
int off = IO.readShort(colName.getRawData(),
_base + 2) + 4;
int len = IO.readShort(colName.getRawData(),
_base + 4);
columnName = IO.readString(colText.getRawData(),
off, len);
}
else
{
columnName = "COL" + i;
}
// Read column labels
String label;
if (colLabels != null && colLabels.Any())
{
_base = 42;
byte[] rawData = colLabels[i].getRawData();
int off = IO.readShort(rawData, _base) + 4;
short len = IO.readShort(rawData, _base + 2);
if (len > 0)
{
label = IO.readString(colText.getRawData(),
off, len);
}
else
{
label = null;
}
}
else
{
label = null;
}
// Read column offset, width, type (required)
_base = 12 + i * 12;
int offset = IO.readInt(colAttr.getRawData(), _base);
columnOffsets.Add(offset);
int length = IO.readInt(colAttr.getRawData(), _base + 4);
columnLengths.Add(length);
short columnTypeCode = IO.readShort(
colAttr.getRawData(), _base + 10);
SasColumnType columnType = (columnTypeCode == 1 ? SasColumnType.NUMERIC
: SasColumnType.CHARACTER);
columnTypes.Add(columnType);
//Logger.Debug(string.Format(
// "Column no. {0} read: name={1},label={2},type={3},length={4}",
// i, columnName, label,
// columnType, length ));
callback.column(i, columnName, label, columnType,
length);
}
subHeadersParsed = true;
}
if (!callback.readData())
{
//Logger.Info("Callback decided to not read data");
return;
}
// Read data
int row_count_p;
int _base2;
if (pageType == 2)
{
row_count_p = row_count_fp;
int subhCount = IO.readInt(pageData, 20);
_base2 = 24 + subhCount * 12;
_base2 = _base2 + _base2 % 8;
}
else
{
row_count_p = IO.readInt(pageData, 18);
_base2 = 24;
}
if (row_count_p > row_count)
{
row_count_p = row_count;
}
for (int row = 0; row < row_count_p; row++)
{
Object[] rowData = new Object[col_count];
for (int col = 0; col < col_count; col++)
{
int off = _base2 + columnOffsets[col];
int len = columnLengths[col];
SasColumnType columnType = columnTypes[col];
if (len > 0)
{
byte[] raw = IO.readBytes(pageData, off, len);
if (columnType == SasColumnType.NUMERIC && len < 8)
{
byte[] bb = new byte[8];
for (int j = 0; j < len; j++)
{
bb[j] = raw[j];
}
for (int j = 0; j < 8 - len; j++)
{
bb[j] = (byte)0x00;
}
raw = bb;
// col$length <- 8
len = 8;
}
Object value;
if (columnType == SasColumnType.CHARACTER)
{
String str = IO.readString(raw, 0, len);
str = str.Trim();
value = str;
}
else
{
value = IO.readNumber(raw, 0, len);
}
rowData[col] = value;
}
}
//Logger.Debug(string.Format("Row no. {0} read: ", row));
//foreach(Object c in rowData)
//{
// Logger.Debug(c);
//}
rowCount++;
bool next = callback.row(rowCount, rowData);
if (!next)
{
//Logger.Info("Callback decided to stop iteration");
return;
}
_base2 = _base2 + row_length;
}
}
}
}
