private static ReadOnlyMemory <byte> ReadPayload(Stream source, int payloadSize)
{
if (payloadSize == 0)
{
return(ReadOnlyMemory <byte> .Empty);
}
var payload = new Memory <byte>(new byte[payloadSize]);
var consumed = 0;
while (true)
{
var read = source.Read(payload.Slice(consumed).Span);
if (read < 1)
{
throw NatsException.OpParserOpParsingError(MsgOp.Name, "Could not read payload from stream.");
}
consumed += read;
if (consumed == payloadSize)
{
break;
}
if (consumed > payloadSize)
{
throw NatsException.OpParserOpParsingError(MsgOp.Name, "Read to many bytes for the payload.");
}
}
return(payload);
}
private static ErrOp ParseErrorOp(Stream source, Stream workspace)
{
while (true)
{
var b = (byte)source.ReadByte();
if (b == Cr)
{
b = (byte)source.ReadByte();
if (b != Lf)
{
throw NatsException.OpParserOpParsingError(ErrOp.Name, Lf, b);
}
break;
}
workspace.WriteByte(b);
}
var buff = new Memory <byte>(new byte[workspace.Position]);
workspace.Position = 0;
workspace.Read(buff.Span);
return(new ErrOp(string.Create(buff.Length, buff, (t, s) =>
{
var x = s.Span;
for (var i = 0; i < t.Length; i++)
{
t[i] = (char)x[i];
}
})));
}
private static PingOp ParsePingOp(Stream source)
{
var c = (byte)source.ReadByte();
if (c != Lf)
{
throw NatsException.OpParserOpParsingError(PingOp.Name, Lf, c);
}
return(PingOp.Instance);
}
private static InfoOp ParseInfoOp(Stream source, Stream workspace)
{
while (true)
{
var b = (byte)source.ReadByte();
if (b == Cr)
{
b = (byte)source.ReadByte();
if (b != Lf)
{
throw NatsException.OpParserOpParsingError(InfoOp.Name, Lf, b);
}
break;
}
workspace.WriteByte(b);
}
var m = ToChars(workspace);
return(new InfoOp(m));
}
private static MsgOp ParseMsgOp(Stream source, Stream workspace)
{
var sub = ReadOnlySpan <char> .Empty;
var sid = ReadOnlySpan <char> .Empty;
var replyTo = ReadOnlySpan <char> .Empty;
int payloadSize;
byte b;
while (true)
{
b = (byte)source.ReadByte();
if (b == Cr)
{
payloadSize = int.Parse(ToChars(workspace).Span);
b = (byte)source.ReadByte();
if (b != Lf)
{
throw NatsException.OpParserOpParsingError(MsgOp.Name, Lf, b);
}
break;
}
if (!IsDelimMarker(b))
{
workspace.WriteByte(b);
}
else
{
if (sub.IsEmpty)
{
sub = ToChars(workspace).Span;
workspace.Position = 0;
continue;
}
if (sid.IsEmpty)
{
sid = ToChars(workspace).Span;
workspace.Position = 0;
continue;
}
if (replyTo.IsEmpty)
{
replyTo = ToChars(workspace).Span;
workspace.Position = 0;
continue;
}
throw NatsException.OpParserOpParsingError(MsgOp.Name, "Message does not conform to expected protocol format.");
}
}
var payload = ReadPayload(source, payloadSize);
b = (byte)source.ReadByte();
if (b != Cr)
{
throw NatsException.OpParserOpParsingError(MsgOp.Name, Cr, b);
}
b = (byte)source.ReadByte();
if (b != Lf)
{
throw NatsException.OpParserOpParsingError(MsgOp.Name, Lf, b);
}
return(new MsgOp(
sub,
sid,
replyTo,
payload));
}
