/// <summary>
/// Parse the input byte stream starting from the given index and populate the Options
/// </summary>
/// <param name="coapMsgStream">The CoAP message stream as bytes (in network byte order)</param>
/// <param name="startIndex">The index to start looking for options</param>
/// <param name="extraInfo">Not used</param>
/// <returns>The next index that points towards payload marker</returns>
public int Parse(byte[] coapMsgStream, int startIndex, UInt16 extraInfo)
{
if (coapMsgStream == null || coapMsgStream.Length <= AbstractCoAPMessage.HEADER_LENGTH ||
startIndex < AbstractCoAPMessage.HEADER_LENGTH || startIndex >= coapMsgStream.Length)
{
return(startIndex); //Nothing to parse...no options present...just point to the next location
}
byte optionHeader = coapMsgStream[startIndex];
UInt16 previousOptionNumber = 0;
int nextIndex = startIndex;
while ((optionHeader & 0xF0) != 0xF0 /*not a payload indicator*/ &&
optionHeader != 0)
{
CoAPHeaderOption headerOption = new CoAPHeaderOption();
nextIndex = headerOption.Parse(coapMsgStream, nextIndex, previousOptionNumber);
this.Add(headerOption);
previousOptionNumber = ((CoAPHeaderOption)this[this.Count - 1]).Number;
if (nextIndex >= coapMsgStream.Length)
{
break;
}
optionHeader = coapMsgStream[nextIndex];
}
return(nextIndex);
}
private void InsertOrderedOption(CoAPHeaderOption o)
{
int i = 0;
for (i = 0; i < this.Count; i++)
{
CoAPHeaderOption h = (CoAPHeaderOption)this[i];
if (o.Number < h.Number)
{
break;
}
}
this.Insert(i, o);
}
/// <summary>
/// Add a new option to the list of options
/// </summary>
/// <param name="optionNumber">The option number</param>
/// <param name="optionValue">The associated option value as UTF-8string. This will be converted to bytes internally</param>
public virtual void AddOption(UInt16 optionNumber, string optionValue)
{
CoAPHeaderOption headerOption = new CoAPHeaderOption(optionNumber, AbstractByteUtils.StringToByteUTF8(optionValue));
if (!headerOption.IsRepeatable() && this.HasOption(optionNumber))
{
//Specs say that if an option is not repeatable and it still appears multiple times,
//each subsequent option must be treated as un-recognized....
//In this implementation, we do not allow non-repetable options to be added to the list
throw new CoAPFormatException("Non-repeatable option already present in collection. Cannot add more.");
}
else
{
this.Add(headerOption);
}
}
