Event dispatch bugfix

[orrmany]

Hi, here comes a bugfix for a missing dereference. Combined with the headache of migration to PlatformIO Core 5.x, this caused me several hours frustration..
Probably I made the original erroneous pull-request into 0.21.0 from the beginning....

[orrmany]

@hathach, maybe we should rename Bluefruit._mprot_event_sem into Bluefruit._mprot_event_sem_p to prevent similar errors?

[orrmany]

Well, I found the commit, which introduced the bug: ff12326 . I made this somehow while I made editorial changes :(

[hathach]

@hathach, maybe we should rename Bluefruit._mprot_event_sem into Bluefruit._mprot_event_sem_p to prevent similar errors?

the semaphore is the pointer itself, maybe you could just use SemaphoreHandle_t to declare _mprot_event_sem and setMultiprotocolSemaphore

[orrmany]

the semaphore is the pointer itself, maybe you could just use `SemaphoreHandle_t` to declare `_mprot_event_sem` and `setMultiprotocolSemaphore`

..but you wanted minimize the ANT support impact on Bluefruit? If I would change the type to `Semaphore_handle_t` instead of `Semaphore_handle_t*`, then we would need to handle the entire life-cycle management of the semaphore inside Adafruit't Bluefruit lib, such as calling `xSemaphoreCreateBinary()`, etc....

[hathach]

semaphore handle is pointer itself, there is no need to handle it within the bluefruit, just set(handle) when created, and set(NULL) before delete by application would work.

[orrmany]

semaphore handle is pointer itself, there is no need to handle it within the bluefruit, just set(handle) when created, and set(NULL) before delete by application would work.

Hmm, that would mean some API change to yet another library I am developing, but maybe your are right. I will come back to you soon

[hathach]

Hmm, that would mean some API change to yet another library I am developing, but maybe your are right. I will come back to you soon

If you don't want to change your lib, that is ok. We can leave it as it is now. Let me know what you decide to do

[orrmany]

Hi @hathach, I have implemented your proposal: as part of the bugfix I made _mprot_event_sem a regular semaphore (and also rebased the bugfix for cleanup)

[hathach]

look good