internal int GetLength(DnsDomainNameCompressionData compressionData, int offsetInDns)
{
int length = 0;
for (int i = 0; i != LabelsCount; ++i)
{
ListSegment <DataSegment> labels = new ListSegment <DataSegment>(_labels, i);
if (compressionData.IsAvailable(labels))
{
return(length + sizeof(ushort));
}
compressionData.AddCompressionData(labels, offsetInDns + length);
length += sizeof(byte) + labels[0].Length;
}
return(length + sizeof(byte));
}
public bool TryGetOffset(ListSegment <DataSegment> labels, out int offsetInDns)
{
switch (DomainNameCompressionMode)
{
case DnsDomainNameCompressionMode.All:
return(_data.TryGetValue(labels, out offsetInDns));
case DnsDomainNameCompressionMode.Nothing:
offsetInDns = 0;
return(false);
default:
throw new InvalidOperationException(string.Format(CultureInfo.InvariantCulture, "Invalid Domain Name Compression Mode {0}",
DomainNameCompressionMode));
}
}
internal int Write(byte[] buffer, int dnsOffset, DnsDomainNameCompressionData compressionData, int offsetInDns)
{
int length = 0;
for (int i = 0; i != LabelsCount; ++i)
{
ListSegment <DataSegment> labels = new ListSegment <DataSegment>(_labels, i);
int pointerOffset;
if (compressionData.TryGetOffset(labels, out pointerOffset))
{
buffer.Write(dnsOffset + offsetInDns + length, (ushort)(CompressionMarker | (ushort)pointerOffset), Endianity.Big);
return(length + sizeof(ushort));
}
DataSegment currentLabel = labels[0];
compressionData.AddCompressionData(labels, offsetInDns + length);
buffer.Write(dnsOffset + offsetInDns + length, (byte)currentLabel.Length);
length += sizeof(byte);
currentLabel.Write(buffer, dnsOffset + offsetInDns + length);
length += currentLabel.Length;
}
return(length + sizeof(byte));
}
public void AddCompressionData(ListSegment <DataSegment> labels, int dnsOffset)
{
if (dnsOffset > DnsDomainName.OffsetMask)
{
return;
}
switch (DomainNameCompressionMode)
{
case DnsDomainNameCompressionMode.All:
if (!_data.ContainsKey(labels))
{
_data.Add(labels, dnsOffset);
}
return;
case DnsDomainNameCompressionMode.Nothing:
return;
default:
throw new InvalidOperationException(string.Format(CultureInfo.InvariantCulture, "Invalid Domain Name Compression Mode {0}",
DomainNameCompressionMode));
}
}
public bool IsAvailable(ListSegment <DataSegment> labels)
{
int offsetInDns;
return(TryGetOffset(labels, out offsetInDns));
}
