public DataHeader getHeader()
{
// get the header information
if (header == null)
{
header = readHeader(filename);
}
// return the header information
return(header);
}
public void close()
{
// threadsafety
lock (lockReader) {
// if a datastream is open, close it
if (dataStream != null)
{
dataStream.Close();
dataStream = null;
}
// clear the header
header = null;
// reset the row index
currentRowIndex = 0;
}
}
public bool open()
{
// threadsafety
lock (lockReader) {
// check if file does not exists
if (!File.Exists(filename))
{
// message
logger.Error("Could not open data file '" + filename + "' for reading");
// return failure
return(false);
}
DataHeader a = getHeader();
// make sure the header is read
// return false if the header could not be read
if (getHeader() == null || string.IsNullOrEmpty(getHeader().code))
{
return(false);
}
try {
// open file stream
dataStream = new FileStream(filename, FileMode.Open);
} catch (Exception) {
// message
logger.Error("Could not create filestream to data file '" + filename + "' for reading");
// return failure
return(false);
}
// set the data pointer to the beginning
resetDataPointer();
// return success
return(true);
} // end lock
}
public static DataHeader readHeader(String fileName)
{
// create a new data header object
DataHeader header = new DataHeader();
FileStream fileStream = null;
try {
// open file stream
fileStream = new FileStream(fileName, FileMode.Open);
// retrieve version number
byte[] bVersion = new byte[sizeof(int)];
fileStream.Read(bVersion, 0, sizeof(int));
header.version = BitConverter.ToInt32(bVersion, 0);
// check version
if (header.version != 1 && header.version != 2)
{
throw new Exception("Unknown data version");
}
// retrieve the code from the header
byte[] bCode = new byte[3];
fileStream.Read(bCode, 0, bCode.Length);
header.code = Encoding.ASCII.GetString(bCode);
// retrieve the epochs (V2)
if (header.version == 2)
{
byte[] bRunStartEpoch = new byte[8];
fileStream.Read(bRunStartEpoch, 0, bRunStartEpoch.Length);
header.runStartEpoch = BitConverter.ToInt64(bRunStartEpoch, 0);
byte[] bFileStartEpoch = new byte[8];
fileStream.Read(bFileStartEpoch, 0, bFileStartEpoch.Length);
header.fileStartEpoch = BitConverter.ToInt64(bFileStartEpoch, 0);
}
// retrieve the sample rate
byte[] bSampleRate = new byte[8];
fileStream.Read(bSampleRate, 0, bSampleRate.Length);
header.sampleRate = BitConverter.ToDouble(bSampleRate, 0);
// retrieve the number of playback input streams
byte[] bNumPlaybackStreams = new byte[4];
fileStream.Read(bNumPlaybackStreams, 0, bNumPlaybackStreams.Length);
header.numPlaybackStreams = BitConverter.ToInt32(bNumPlaybackStreams, 0);
// # streams + streams details (V2)
if (header.version == 2)
{
byte[] bNumStreams = new byte[4];
fileStream.Read(bNumStreams, 0, bNumStreams.Length);
header.numStreams = BitConverter.ToInt32(bNumStreams, 0);
for (int i = 0; i < header.numStreams; i++)
{
byte[] bStreamDataType = new byte[1];
fileStream.Read(bStreamDataType, 0, bStreamDataType.Length);
header.streamDataTypes.Add(bStreamDataType[0]);
byte[] bStreamSamplesPer = new byte[2];
fileStream.Read(bStreamSamplesPer, 0, bStreamSamplesPer.Length);
header.streamDataSamplesPerPackage.Add(BitConverter.ToUInt16(bStreamSamplesPer, 0));
}
}
// retrieve the number of columns
byte[] bNumColumns = new byte[4];
fileStream.Read(bNumColumns, 0, bNumColumns.Length);
header.numColumns = BitConverter.ToInt32(bNumColumns, 0);
// retrieve the size of the column names
byte[] bColumnNamesSize = new byte[4];
fileStream.Read(bColumnNamesSize, 0, bColumnNamesSize.Length);
header.columnNamesSize = BitConverter.ToInt32(bColumnNamesSize, 0);
// retrieve the column names from the header
byte[] bColumnNames = new byte[header.columnNamesSize];
fileStream.Read(bColumnNames, 0, header.columnNamesSize);
header.columnNames = Encoding.ASCII.GetString(bColumnNames).Split('\t');
//
// calculate worker variables
//
// store the position where the data starts (= the current position of the pointer in the stream after reading the header)
header.posDataStart = fileStream.Position;
if (header.version == 1)
{
// determine the rowsize based on the header code (src/dat or plugin file)
if (header.code == "src" || header.code == "dat")
{
header.rowSize = sizeof(uint); // sample id
header.rowSize += (header.numColumns - 1) * sizeof(double); // data
}
else
{
header.rowSize = header.numColumns * sizeof(double); // sampleid <double> + stream values
}
// determine the number of rows
// casting to integer will make numrows round down in case of incomplete rows
header.numRows = (fileStream.Length - header.posDataStart) / header.rowSize;
}
else if (header.version == 2)
{
// determine the highest number of samples that any data stream in the pipeline would want to log
header.maxSamplesStream = 0;
for (int i = 0; i < header.numStreams; i++)
{
if (header.streamDataSamplesPerPackage[i] > header.maxSamplesStream)
{
header.maxSamplesStream = header.streamDataSamplesPerPackage[i];
}
}
}
} catch (Exception) {
// close the data stream
if (fileStream != null)
{
fileStream.Close();
}
// return failure
return(null);
} finally {
// close the data stream
if (fileStream != null)
{
fileStream.Close();
}
}
return(header);
}
/**
* Create header of .dat (plugin or filter) or .src file
*
* boolean timing either includes (true) or excludes (false) extra column in header file for storing elapsed time
**/
public static void writeBinaryHeader(FileStream writer, DataHeader header)
{
// retrieve code into local variable
string headerCode = header.code;
// make sure the header code is always 3 characters long
if (headerCode.Length != 3)
{
headerCode = "xxx";
}
// determine whether the header is a plugin
bool isPlugin = !(string.Compare(headerCode, "src") == 0 || string.Compare(headerCode, "dat") == 0);
//
// prepare column names
//
// variable holding the column names and columncount
string columnNames = "";
int numColumns = 0;
// add sample id column
if (header.version == 1)
{
columnNames += "Sample\t";
}
else if (header.version == 2)
{
columnNames += "SamplePackage\t";
}
numColumns++;
// add elapsed column (when not plugin)
if (!isPlugin)
{
columnNames += "Elapsed_ms\t";
numColumns++;
}
// add stream names to the local variable of that holds all the column names
columnNames += string.Join("\t", header.columnNames);
numColumns += header.columnNames.Length;
// convert column names to binary
byte[] columnNamesBinary = Encoding.ASCII.GetBytes(columnNames);
//
// write header
//
// version
byte[] versionBinary = BitConverter.GetBytes(header.version);
writer.Write(versionBinary, 0, versionBinary.Length);
// code
byte[] headerCodeBinary = Encoding.ASCII.GetBytes(headerCode);
writer.Write(headerCodeBinary, 0, headerCodeBinary.Length);
// epochs
if (header.version == 2)
{
byte[] headerRunStartEpoch = BitConverter.GetBytes(header.runStartEpoch);
writer.Write(headerRunStartEpoch, 0, headerRunStartEpoch.Length);
byte[] headerFileStartEpoch = BitConverter.GetBytes(header.fileStartEpoch);
writer.Write(headerFileStartEpoch, 0, headerFileStartEpoch.Length);
}
// sample rate
byte[] sampleRateBinary = BitConverter.GetBytes(header.sampleRate);
writer.Write(sampleRateBinary, 0, sampleRateBinary.Length);
// playback streams
byte[] numPlaybackInputStreamsBinary = BitConverter.GetBytes(header.numPlaybackStreams);
writer.Write(numPlaybackInputStreamsBinary, 0, numPlaybackInputStreamsBinary.Length);
// # streams + streams details (V2)
if (header.version == 2)
{
byte[] numStreamsBinary = BitConverter.GetBytes(header.numStreams);
writer.Write(numStreamsBinary, 0, numStreamsBinary.Length);
for (int i = 0; i < header.numStreams; i++)
{
writer.Write(new byte[] { header.streamDataTypes[i] }, 0, 1);
byte[] streamDataSamplesBinary = BitConverter.GetBytes(header.streamDataSamplesPerPackage[i]);
writer.Write(streamDataSamplesBinary, 0, streamDataSamplesBinary.Length);
}
}
// # columns, column-names byte-length and names
byte[] numColumnsBinary = BitConverter.GetBytes(numColumns);
writer.Write(numColumnsBinary, 0, numColumnsBinary.Length);
byte[] columnNamesLengthBinary = BitConverter.GetBytes(columnNamesBinary.Length);
writer.Write(columnNamesLengthBinary, 0, columnNamesLengthBinary.Length);
writer.Write(columnNamesBinary, 0, columnNamesBinary.Length);
// Note: don't close writer. Data could/will be written after this
}
