private IEnumerable <IToken> ParseInternal(Stream stream, DbEnvironment env)
{
IFormatToken previousFormatToken = null;
while (stream.Position < stream.Length)
{
var tokenType = (TokenType)stream.ReadByte();
if (Readers.ContainsKey(tokenType))
{
var t = Readers[tokenType](stream, env, previousFormatToken);
if (t is IFormatToken token)
{
Logger.Instance?.WriteLine($"**Set new format token**");
previousFormatToken = token;
}
yield return(t);
}
else
{
Logger.Instance?.WriteLine($"!!! Hit unknown token type {tokenType} !!!");
var t = new CatchAllToken(tokenType);
t.Read(stream, env, previousFormatToken);
yield return(t);
}
}
}
public void ZeroLengthToken_NoBytesRead(string _, byte type)
{
var t = new CatchAllToken(type);
using (var ms = new MemoryStream())
{
t.Read(ms, new DbEnvironment(), null);
Assert.AreEqual(0, ms.Position);
}
}
public void ZeroLengthToken_NoBytesRead(string _, byte type)
{
var t = new CatchAllToken(type);
using (var ms = new MemoryStream())
{
// All zero-length tokens are not actually zero-length.
// They have a length, but it is derived from prior tokens (eg TDS_ALTROW's length is determined by a prior TDS_ALTFMT token)
// As such, we cannot process the tokens with Catch-All without corrupting the stream's next-token position
Assert.Throws <InvalidOperationException>(() => t.Read(ms, new DbEnvironment(), null));
}
}
public void FixedLengthToken_FixedBytesRead(string _, byte type, int dataLength)
{
var t = new CatchAllToken(type);
using (var ms = new MemoryStream())
{
ms.Write(new byte[dataLength]);
ms.Seek(0, SeekOrigin.Begin);
t.Read(ms, new DbEnvironment(), null);
Assert.AreEqual(ms.Length, ms.Position);
}
}
public void VariableLengthToken_UIntLength_VariableBytesRead(string _, byte type)
{
uint dataLength = 10;
var t = new CatchAllToken(type);
using (var ms = new MemoryStream())
{
ms.WriteUInt(dataLength);
ms.Write(new byte[dataLength]);
ms.Seek(0, SeekOrigin.Begin);
t.Read(ms, new DbEnvironment(), null);
Assert.AreEqual(ms.Length, ms.Position);
}
}
public IEnumerable <IToken> Read(TokenReceiveStream stream, DbEnvironment env)
{
IFormatToken previousFormatToken = null;
while (stream.DataAvailable)
{
var rawTokenType = (byte)stream.ReadByte();
var tokenType = (TokenType)rawTokenType;
if (Readers.ContainsKey(tokenType))
{
var t = Readers[tokenType](stream, env, previousFormatToken);
if (t is IFormatToken token)
{
Logger.Instance?.WriteLine($"**Set new format token**");
previousFormatToken = token;
}
yield return(t);
}
else
{
Logger.Instance?.WriteLine($"!!! Hit unknown token type {tokenType} !!!");
var t = new CatchAllToken(rawTokenType);
t.Read(stream, env, previousFormatToken);
yield return(t);
}
if (stream.IsCancelled)
{
Logger.Instance?.WriteLine($"{nameof(TokenReceiveStream)} - received cancel status flag");
yield return
(new DoneToken
{
Count = 0,
Status = DoneToken.DoneStatus.TDS_DONE_ATTN
});
}
}
}
