/// <summary>
/// Initializes a new instance of the <see cref="PacketDotNet.Ieee80211.PpiPacket"/> class.
/// </summary>
/// <param name='bas'>
/// A <see cref="ByteArraySegment"/>
/// </param>
public PpiPacket(ByteArraySegment bas)
{
// slice off the header portion
header = new ByteArraySegment(bas);
Version = VersionBytes;
Flags = FlagsBytes;
// update the header size based on the headers packet length
header.Length = LengthBytes;
LinkType = LinkTypeBytes;
PpiFields = ReadPpiFields();
PpiCommon commonField = FindFirstByType(PpiFieldType.PpiCommon) as PpiCommon;
// parse the encapsulated bytes
payloadPacketOrData = ParseEncapsulatedBytes(header, commonField);
}
/// <summary>
/// Used by the Ieee80211PpiPacket constructor.
/// </summary>
/// <param name="header">
/// A <see cref="ByteArraySegment"/>
/// </param>
/// <param name="commonField">
/// The <see cref="PpiCommon"/> object in the PPI packet or null if not available
/// </param>
/// <returns>
/// A <see cref="PacketOrByteArraySegment"/>
/// </returns>
internal static PacketOrByteArraySegment ParseEncapsulatedBytes(ByteArraySegment header, PpiCommon commonField)
{
// slice off the payload
var payload = header.EncapsulatedBytes();
var payloadPacketOrData = new PacketOrByteArraySegment();
MacFrame frame = null;
if (commonField != null)
{
bool fcsPresent = ((commonField.Flags & PpiCommon.CommonFlags.FcsIncludedInFrame) == PpiCommon.CommonFlags.FcsIncludedInFrame);
if (fcsPresent)
{
frame = MacFrame.ParsePacketWithFcs(payload);
}
else
{
frame = MacFrame.ParsePacket(payload);
}
}
else
{
frame = MacFrame.ParsePacket(payload);
}
if (frame == null)
{
payloadPacketOrData.TheByteArraySegment = payload;
}
else
{
payloadPacketOrData.ThePacket = frame;
}
return(payloadPacketOrData);
}
