//=========================================================================
/// <summary>
/// Initialise with an incoming msg. This interpreter now has a copy of the message.
/// </summary>
/// <param name="inMsg"></param>
/// <returns></returns>
//=========================================================================
public bool loadMessage(TMsgHeader inMsg)
{
int iFld;
bool result;
if (!inMsg.Equals(null)) //if there is a message header
{
//need to do a cleanup in case the interpreter has any existing msg's
for (iFld = 1; (iFld <= Msgs.MAX_FLDS) && (initArray[iFld - 1].fieldType != TTypedValue.TBaseType.ITYPE_EMPTY); iFld++)
{
if (initArray[iFld - 1].size > 0)
{
freeInitArrayItem(iFld);
}
}
//take ownership of the msg header and data block
msg = inMsg; //now I own the msg because I will delete it later
result = true;
}
else
{
result = false;
}
return(result);
}
//=========================================================================
/// <summary>
/// Determines the offset for a particular field in the msg data block. Adds
/// all the item sizes and uses the char[] block information to determine the
/// size of the char[] strings.
/// </summary>
/// <param name="fieldID">Field ID e.g. 14001</param>
/// <returns>The offset count from the start of the data block to find the
/// field data.</returns>
//=========================================================================
private uint calcOffset(int fieldID)
{
int iFieldNo;
int iFld; //field number along the block
int iFldType;
uint offset = 0; //ptr offset counter
int strSize;
if ((!msg.Equals(null)) && (msg.dataPtr.Length > 0))
{ //check that a message and data block exist
iFieldNo = fieldID % 1000;
for (iFld = 1; iFld < iFieldNo; iFld++)
{
iFldType = msgSpec[msg.msgType - 1].fld[iFld - 1];
if (iFldType == (int)TTypedValue.TBaseType.ITYPE_STR)
{
strSize = BitConverter.ToInt32(msg.dataPtr, (int)offset); //get the size of the char string
offset += TTypedValue.typeSize[(int)TTypedValue.TBaseType.ITYPE_INT4] + (uint)strSize; //add 4byte size DIM + length of string
}
else
{
offset += TTypedValue.typeSize[iFldType];
}
}
}
if (msg.nDataBytes < offset)
{
string errorMsg = string.Format("Error determining offset of field {0} from msg {1}", fieldID, msg.msgType);
throw (new ApplicationException(errorMsg));
}
return(offset);
}
//============================================================================
/// <summary>
/// Test if the msg is defined.
/// </summary>
/// <param name="msg"></param>
/// <returns>True if msg == TMessageHdrList.Null</returns>
//============================================================================
public Boolean IsNull(TMsgHeader msg)
{
return(msg.Equals(Null));
}