Re: [Hamlib-developer] rig_caps_register

[Stephane F. <f4...@fr...>]

Frank Singleton wrote:
> 
> In order for rig.c to populate the  rig_caps array automagically,as
> suggested
> 
[..]
> We could have backend call a frontend rig_caps_register function that
> simple passes an address of their own cap structure into
> the rig_caps array in rig.c
> 
> ie:
> 
> int rig_caps_register(RIG *rig) {
> 
you mean	int rig_caps_register(const struct rig_caps *my_backend_caps)

> .... insert cap ptr into rig_base[]
> .... and return result to caller
> 
> }
> 
> This way,  frontend can init all backends via a rig_backend_poll()
> function. backends must respond by registering their caps,
> rig_caps_register() and
> any other things we may add in future :-)
> 
  So if I understand correctly, the rig_backend_poll() function
  (called by who?) would call some backend initializer function
  (constructor?) that would in term call rig_caps_register().
  Well, this is not too far fetched, especially if you consider
  the dlopen/_init facility (in case of external loadable modules).

> This way 
> 
> rig_caps *rig_base[MAX_RIG_CAPS]  will be 
> dynamically populated.
> 
> eg:
> 
> frontend                   backend
> --------                   -------
> 
> for all rigs do

   gotcha! there you still have to have a backend array with pointer to
   functions, or at least explicitly reference all the backend
   constructors.
> 
>       rig_backend_poll
>     --------------------->
> 
>          rig_caps_regisyter
>      <---------------------  ft747_caps
> 
>       rig_backend_poll
>     --------------------->
> 
[...]

> rig_base[] is now populated ...
> 
> 
> The rig_backend_poll could be done at
> loading of the frontend libhamlib library that
> can access all the backends.
> 
  This idea needs some maturation, let's think about it,
  see how we can work it out.


> Also, should we have 1 lib "libhamlib"
> that contains the frontend and all the backends (easy), or
> should we load frontend "libhamlib" and he can
> dynamically load backend libraries on demand.
> This second option is probably more 
> professional ;-)

  and also more fun :-) 
  As usual, I think both are good, like in SANE (no pun here :)

-- 
Stephane Fillod					F4CFE