/// <summary>
/// Reads the FIT binary file header and crc to check compatibility and integrity.
/// Also checks data reords size.
/// Returns true if file is ok (not corrupt).
///</summary>
/// <param name="fitStream">Seekable (file)stream to parse.</param>
public bool CheckIntegrity(Stream fitStream)
{
bool isValid;
try
{
// Is there a valid header?
Header header = new Header(fitStream);
isValid = header.IsValid();
// Are there as many data bytes as the header claims?
isValid &= ((header.Size + header.DataSize + 2) == fitStream.Length);
// Is the file CRC ok?
byte[] data = new byte[fitStream.Length];
fitStream.Position = 0;
fitStream.Read(data, 0, data.Length);
isValid &= (CRC.Calc16(data, data.Length) == 0x0000);
return isValid;
}
catch(FitException)
{
return false;
}
}
/// <summary>
/// Reads a FIT binary file.
/// </summary>
/// <param name="fitStream">Seekable (file)stream to parse.</param>
/// <returns>
/// Returns true if reading finishes successfully.
/// </returns>
public bool Read(Stream fitStream)
{
bool readOK = true;
try
{
// Attempt to read header
fileHeader = new Header(fitStream);
readOK &= fileHeader.IsValid();
if (!readOK)
{
throw new FitException("FIT decode error: File is not FIT format. Check file header data type.");
}
if ((fileHeader.ProtocolVersion & Fit.ProtocolVersionMajorMask) > (Fit.ProtocolMajorVersion << Fit.ProtocolVersionMajorShift))
{
// The decoder does not support decode accross protocol major revisions
throw new FitException(String.Format("FIT decode error: Protocol Version {0}.X not supported by SDK Protocol Ver{1}.{2} ", (fileHeader.ProtocolVersion & Fit.ProtocolVersionMajorMask) >> Fit.ProtocolVersionMajorShift, Fit.ProtocolMajorVersion, Fit.ProtocolMinorVersion));
}
// Read data messages and definitions
while (fitStream.Position < fitStream.Length - 2)
{
DecodeNextMessage(fitStream);
}
// Is the file CRC ok?
byte[] data = new byte[fitStream.Length];
fitStream.Position = 0;
fitStream.Read(data, 0, data.Length);
readOK &= (CRC.Calc16(data, data.Length) == 0x0000);
}
catch (EndOfStreamException e)
{
readOK = false;
Debug.WriteLine("{0} caught and ignored. ", e.GetType().Name);
throw new FitException("Decode:Read - Unexpected End of File", e);
}
return readOK;
}
/// <summary>
/// Reads the file header to check if the file is FIT.
/// Does not check CRC.
/// Returns true if file is FIT.
/// </summary>
/// <param name="fitStream"> Seekable (file)stream to parse</param>
public bool IsFIT(Stream fitStream)
{
try
{
// Does the header contain the flag string ".FIT"?
Header header = new Header(fitStream);
return header.IsValid();
}
// If the header is malformed the ctor could throw an exception
catch (FitException)
{
return false;
}
}