Experimental Physics and
Industrial Control System

Michael Davidsaver <[email protected]> · Mon, 18 Aug 2014 13:51:03 -0400

On 08/18/2014 01:06 PM, Andrew Johnson wrote:
> ...
>>> Has extending the DB syntax to cover array data been considered at some 
>>> point?
> 
> This will require a change to the record-type interface (RSET) because
> currently it is the record's responsibility to allocate memory for its
> array fields, which can't be done right now until iocInit().

I see no technical requirement to change the interface.

>> One of changes I'm considering (after the linking/locking work) is to
>> re-write the DBD file parser.
> 
> The IOC doesn't really need a DBD file parser at all (although it will
> still need a DB file parser),

Forgive me for being imprecise.  I've never been sure how to refer to
the common syntax of these two file types.

> ...I started that work some time back, and would like to finish it.

:)

>> The idea would be to parse into an intermediate structure which would be
>> more general than dbStatic.  This would define points in the syntax for
>> future expansion, and avoid some of the chicken and egg problems of the
>> present code.
>> 
>> For this specific use case, the intermediate structure would provide an
>> obvious place to keep the original field value text.  Of course this
>> tracking could also be grafted on to dbRecordNode as the info() tags where.
> 
> I will explicitly point out the increased memory requirement to store
> all the original DB field values as text.

Yup.  Strictly speaking, it is only necessary to do this for fields with
SPC_DBADDR.  This shouldn't be a big hit in memory usage.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System