public static void WriteValueString(WritableBuffer buffer, string value, HeaderOptions options)
{
switch (options & HeaderOptions.ValueCompressionMask)
{
case HeaderOptions.ValueCompressionAutomatic:
var len = HuffmanCode.GetByteCount(value);
if (len < value.Length)
{
WriteUInt32(buffer, (uint)len, 0x80, 7);
HuffmanCode.Write(buffer, value);
}
else
{
WriteUInt32(buffer, (uint)value.Length, 0, 7);
buffer.WriteAsciiString(value);
}
break;
case HeaderOptions.ValueCompressionOn:
len = HuffmanCode.GetByteCount(value);
WriteUInt32(buffer, (uint)len, 0x80, 7);
HuffmanCode.Write(buffer, value);
break;
case HeaderOptions.ValueCompressionOff:
WriteUInt32(buffer, (uint)value.Length, 0, 7);
buffer.WriteAsciiString(value);
break;
default:
throw new InvalidOperationException("Invalid value compression: " + options);
}
}
public static string ReadString(ref ReadableBuffer buffer, out bool compressed)
{
int header = buffer.Peek();
if (header < 0)
{
ThrowEndOfStreamException();
}
compressed = (header & 0x80) != 0;
buffer = buffer.Slice(1);
int len = checked ((int)ReadUInt64(ref buffer, header, 7));
string result;
if (compressed)
{
result = HuffmanCode.ReadString(buffer.Slice(0, len));
}
else
{
result = buffer.Slice(0, len).GetAsciiString();
}
buffer = buffer.Slice(len);
return(result);
}
private static unsafe string ReadString(ReadableBuffer buffer, char *c, int maxLen)
{
var reader = new HuffmanCode(buffer);
for (int i = 0; i < maxLen; i++)
{
int next = reader.ReadNext();
if (next < 0)
{
return(i == 0 ? "" : new string(c, 0, i));
}
c[i] = (char)next;
}
if (reader.ReadNext() < 0)
{
return(new string(c, 0, maxLen));
}
throw new EndOfStreamException();
}
