[Nut-upsdev] RFC: allow HID subdriver's to register ups.conf settings

[j T]

Hi

I'd like to know what you guys think to the following idea.

Please be aware, C/C++ are not exactly my strongpoint (couldn't be much 
further from it actually..!), so I'm not sure whether this is all legal 
code.

--

SYNOPSIS:

Allow a newhidups subdriver to register that it can handle settings in 
ups.conf (and via -x on the command line), as per the normal serial drivers.

DESCRIPTION OF CHANGES:

- In newhidups.h, add an extra line to the subdriver_s struct;

                void (*extendvartable)(void);

  so it becomes;

        struct subdriver_s {
                char *name;
                int (*claim)(HIDDevice *hd);
                usage_tables_t *utab;
                hid_info_t *hid2nut;
                int (*shutdown)(int ondelay, int offdelay);
                char *(*format_model)(HIDDevice *hd);
                char *(*format_mfr)(HIDDevice *hd);
                char *(*format_serial)(HIDDevice *hd);
                void (*extendvartable)(void);
        };

- In the subdriver source, add an extra function, 
subdriver_extendvartable(). I'm currently
  working on belkin-hid.c, so it would have;

        void belkin_extendvartable(void) {
                addvar(VAR_FLAG, "wait", "Wait for AC power                  
          ");
                addvar(VAR_VALUE,"wait", "Wait for AC power and battery 
level ");
                /* ... */
        }

  The other HID drivers, I guess, could simply have empty functions at the 
moment.

  Next, modify the subdriver_t chunk (again, this is shown for the 
belkin-hid) to be;

        subdriver_t belkin_subdriver = {
                BELKIN_HID_VERSION,
                belkin_claim,
                belkin_utab,
                belkin_hid2nut,
                belkin_shutdown,
                belkin_format_model,
                belkin_format_mfr,
                belkin_format_serial,
                belkin_extendvartable,
        };

- In newhidups.c, at the end of upsdrv_makevartable(), add a single line 
that does:

                subdriver->extendvartable();

  to actually extend the table of configuration options for the specific 
subdriver.

--

Assuming that this sounds like a good idea, I also have a query;

With respect to the subdriver_s struct, would it be better to have the "void 
(*extendvartable) (void);" line at the end of the struct (as shown above), 
or would some other position within the struct be more appropriate???

Thanks

Jo Turner
  -)O(-