public void Test_TAGHeader_Read()
{
using (var reader = new TAGReader(new FileStream(Path.Combine("TestData", "TAGFiles", "TestTAGFile-TAG-Header-Read.tag"), FileMode.Open)))
{
Assert.NotNull(reader);
TAGHeader header = new TAGHeader();
//Read the header
header.Read(reader);
Assert.Equal(1U, header.DictionaryID);
Assert.Equal(1U, header.DictionaryMajorVer);
Assert.Equal(4U, header.DictionaryMinorVer);
Assert.Equal(1U, header.MajorVer);
Assert.Equal(0U, header.MinorVer);
Assert.True(
header.FieldAndTypeTableOffset > 0 && header.FieldAndTypeTableOffset < reader.StreamSizeInNybbles / 2,
"Field and type table offset read from header is invalid");
}
}
/// <summary>
/// Reads the context of a TAG file using the provided reader and sink
/// </summary>
/// <param name="reader"></param>
/// <param name="sink"></param>
/// <returns></returns>
public TAGReadResult Read(TAGReader reader, TAGValueSinkBase sink)
{
try
{
if (reader.StreamSizeInNybbles == 0)
{
return(TAGReadResult.ZeroLengthFile);
}
try
{
Header.Read(reader);
}
catch (Exception E)
{
Log.LogError(E, "Invalid tag file. Exception in TTagFile.ReadStream - Header.LoadFromStream:");
return(TAGReadResult.InvalidDictionary);
}
// If the offset to the dictionary is zero, then it follows immediately after the header
long DataEndPos;
try
{
if (Header.FieldAndTypeTableOffset != 0)
{
long StreamPos = reader.NybblePosition;
reader.NybblePosition = Header.FieldAndTypeTableOffset * 2; // FieldAndTypeTableOffset is in bytes
if (!Dictionary.Read(reader))
{
return(TAGReadResult.InvalidDictionary);
}
reader.NybblePosition = StreamPos;
DataEndPos = Header.FieldAndTypeTableOffset * 2; // FieldAndTypeTableOffset is in bytes
}
else
{
if (!Dictionary.Read(reader))
{
return(TAGReadResult.InvalidDictionary);
}
DataEndPos = reader.StreamSizeInNybbles;
}
}
catch (Exception E)
{
Log.LogWarning(E, "Exception in TagFile.ReadFile:");
return(TAGReadResult.InvalidDictionary);
}
// Now read in the data from the file
if (!sink.Starting())
{
return(TAGReadResult.SinkStartingFailure);
}
while (!sink.Aborting() && reader.NybblePosition < DataEndPos)
{
if (!reader.ReadVarInt(out short ValueTypeID))
{
if (reader.NybblePosition >= DataEndPos)
{
break; // We have finished
}
return(TAGReadResult.InvalidValueTypeID); // This is an invalid tag file
}
if (Dictionary.Entries.Keys.Count == 0)
{
return(TAGReadResult.InvalidDictionary);
}
if (!Dictionary.Entries.TryGetValue(ValueTypeID, out TAGDictionaryItem DictionaryEntry))
{
return(TAGReadResult.InvalidValueTypeID);
}
try
{
switch (DictionaryEntry.Type)
{
case TAGDataType.t4bitInt:
case TAGDataType.t8bitInt:
case TAGDataType.t12bitInt:
case TAGDataType.t16bitInt:
case TAGDataType.t32bitInt:
sink.ReadIntegerValue(DictionaryEntry, reader.ReadSignedIntegerValue(IntegerNybbleSizes.Nybbles[(byte)DictionaryEntry.Type]));
break;
case TAGDataType.t4bitUInt:
case TAGDataType.t8bitUInt:
case TAGDataType.t12bitUInt:
case TAGDataType.t16bitUInt:
case TAGDataType.t32bitUInt:
sink.ReadUnsignedIntegerValue(DictionaryEntry, reader.ReadUnSignedIntegerValue(IntegerNybbleSizes.Nybbles[(byte)DictionaryEntry.Type]));
break;
case TAGDataType.tIEEESingle:
sink.ReadIEEESingleValue(DictionaryEntry, reader.ReadSinglePrecisionIEEEValue());
break;
case TAGDataType.tIEEEDouble:
sink.ReadIEEEDoubleValue(DictionaryEntry, reader.ReadDoublePrecisionIEEEValue());
break;
case TAGDataType.tANSIString:
sink.ReadANSIStringValue(DictionaryEntry, reader.ReadANSIString());
break;
case TAGDataType.tUnicodeString:
sink.ReadUnicodeStringValue(DictionaryEntry, reader.ReadUnicodeString());
break;
case TAGDataType.tEmptyType:
sink.ReadEmptyValue(DictionaryEntry);
break;
}
}
catch (Exception E)
{
Log.LogError(E, "Exception in TagFile.ReadFile while reading field value:");
return(TAGReadResult.InvalidValue);
}
}
if (!sink.Finishing())
{
return(TAGReadResult.SinkFinishingFailure);
}
}
catch (IOException E)
{
Log.LogDebug(E, "Exception in TagFile.ReadFile:");
return(TAGReadResult.CouldNotOpenFile);
}
return(TAGReadResult.NoError);
}