Apologies, I missed this (email and generally in the 1.0 dev) but please do
support this, as it's pretty much a mandatory requirement for being able to
create GATT services (and set-up advertising data) after the OS started,
using an embedded scripting language.
Thanks,
Wayne
On 28 April 2017 at 00:05, Christopher Collins <ch...@runtime.io> wrote:
> Hi Pritish,
>
> On Thu, Apr 27, 2017 at 03:49:34PM -0700, Pritish Gandhi wrote:
> > Hi All,
> > I have a generic question about the nimBLE capabilities. I'm trying to
> > build a BLE GATT server which has a set of services (say services A and
> B).
> > However, these services need to be registered dynamically. What I mean is
> > that when I boot up I won't know which services I need to register with
> the
> > GATT server. I'd like to boot up, probe around a bit, and then make a
> > decision on whether I want to register and then advertise either service
> A
> > only, service B only, or both.
> >
> > However I'm not quite sure I see a way to do that. It seems like services
> > need to be added and registered before the os runs.
> >
> > Here's what the comment says in ble_gatts.c
> > /**
> > * Queues a set of service definitions for registration. All services
> > queued
> > * in this manner get registered when ble_hs_init() is called.
> > *
> > * @param svcs An array of service definitions to queue
> for
> > * registration. This array must be
> > * terminated with an entry whose 'type'
> > * equals 0.
> > *
> > * @return 0 on success;
> > * BLE_HS_ENOMEM on heap exhaustion.
> > */
> >
> > Is what I'm expecting to do not possible?
>
> What you're expecting is almost possible, but it is not a use case that
> the host API allows. The issue is that host starts itself as soon as
> the OS is started, at which point it is too late to register additional
> GATT services.
>
> There is a fairly simple hack that I believe should make this possible:
>
> 1. Modify ble_hs_event_start() (ble_hs.c) such that it is a no-op:
>
> --- a/net/nimble/host/src/ble_hs.c
> +++ b/net/nimble/host/src/ble_hs.c
> @@ -388,10 +388,12 @@ ble_hs_event_reset(struct os_event *ev)
> static void
> ble_hs_event_start(struct os_event *ev)
> {
> +#if 0
> int rc;
>
> rc = ble_hs_start();
> assert(rc == 0);
> +#endif
> }
>
> 2. Call ble_hs_start() from your application after you have finished
> registering services.
>
> This seems like a pretty useful behavior, so it might be worth making
> this configurable in future versions.
>
> Chris
>
