Hello all,
I was looking at adding support for UK ISUP (UK PNO/ISC Spec ND1007:2004/11)
to Ethereal. The UK national version of ISUP consists of
additional/modified parameters and field values so should not be that
difficult to implement but it looks as if I am in danger of working at cross
purposes with other developments.
I am a tester not a programmer and any programming I do tends to take a long
time but, as far as I can see, I have two basic problems:
1. getting the hooks into the dissector to support several different
national options - the latest version of my code (based on 0.10.14) is
attached which could support multiple options based on a user preference.
Is this a sensible way to go and could it co-exist with the ANSI support?
Is there any requirement to support more than one variant at a time?
2. is there a better way to do this than having lots of switch statements?
This may be OK for the parameters where you only execute the code when the
parameter is present but something like it needs to be in the code to decode
a lot of the field values which could affect performance. Is there a better
way than changing
g_snprintf(param_name, NAME_SIZE, val_to_str(upgraded_parameter,
isup_parameter_type_value, "unknown"));
to something like
switch(isup_national){
case NATIONAL_UKISUP:
if(upgraded_parameter>=PARAM_TYPE_NATIONAL_244
&& upgraded_parameter<=PARAM_TYPE_NATIONAL_254)
g_snprintf(param_name, NAME_SIZE,
val_to_str(upgraded_parameter, isup_uknational_parameter_type_value,
"unknown"));
else
g_snprintf(param_name, NAME_SIZE,
val_to_str(upgraded_parameter, isup_parameter_type_value, "unknown"));
break;
<<<repeat for any other national options>>>
default:
g_snprintf(param_name, NAME_SIZE, val_to_str(upgraded_parameter,
isup_parameter_type_value, "unknown"));
}
All advice, comments and suggestions welcome.
Regards
Mike
PS The attached code is an example only - it doesn't do anything useful yet.
Attachment:
packet-isup.zip
Description: Zip compressed data
