esp32 support

[Xavrax]

feat: ESP32 platform support
Provided support for ESP32 devices via ESP-IDF framework

feat: MBedTLS support
Provided support for MBedTLS library used within esp32 platform

refactor: strcpy instead of strncpy when it is safe
Replace strncpy with strcpy in blocks where it is safer to be used.

[blake-spangenberg]

Greetings,

I'm working with Insteon and am eagerly awaiting the completion of esp support for the PubNub SDK. Seeing as this port is nearing completion, I have experimented with integrating it into our project have have some feedback as a result of that experiment:

• In core/pubnub_alloc_static.c, pubnub_alloc relies on local static FreeRTOS mutexes, but there is nothing in that file which calls pubnub_mutex_init on them, thus causing an exception at runtime for our project:

pubnub_t *pubnub_alloc(void)
{
    size_t i;

    for (i = 0; i < PUBNUB_CTX_MAX; ++i) {
        // Something like this is needed...
        // if (!m_aCtx[i].monitor) {
        //    pubnub_mutex_init(m_aCtx[i].monitor)
        // }
        pubnub_mutex_lock(m_aCtx[i].monitor);
        if (m_aCtx[i].state == PBS_NULL) {
            m_aCtx[i].state = PBS_IDLE;
            pubnub_mutex_unlock(m_aCtx[i].monitor);
            return m_aCtx + i;
        }
        pubnub_mutex_unlock(m_aCtx[i].monitor);
    }

    return NULL;
}

• Would you consider incorporating this into espressif’s Component Registry? Their guide is provided here. This would be a great opportunity for you as it could make your service much more discoverable to those exploring the ESP32 for future projects. For us, it would greatly simplify the process of keeping up-to-date with the latest release of your SDK.

[Xavrax]

Hello @blake-spangenberg !
At the end of the week I've changed a little bit a source to test the SDK over the qemu emulator.
I was able to test our pub/sub utility without any errors.
Right now I'm polishing the code to ensure that it works with other features and remove all the magic hacks and totos I've made during the process.

We're planning to release it this week but if you will notice any other issues with the code - let us know about it. We want to be sure that our product satisfies our customer needs <3.

[Xavrax]

Would you consider incorporating this into espressif’s Component Registry? Their guide is provided here.

That's a great idea. I will take a look into that and I will try to satisfy all the needs required by the registry.

[Xavrax]

@blake-spangenberg
We've asked our legals if we're okay with this 3rd party service.
I will let you know about the decision as soon as it will be made.

Until then you will need to rawly git clone the repository.
(hopefully they will allow us to publish our repo there and the SDK will be available at the registry to make the developer experience at the highest level - we've made same thing for rust's SDK so it shouldn't be a problem).

[parfeon]

LGTM!

There are few small questions.

[Xavrax]

@pubnub-release-bot release

[pubnub-release-bot]

🚀 Release successfully completed 🚀

[blake-spangenberg]

Can confirm publish/subscribe is working on our esp32-based hardware platform. Thanks for the hard work everyone!

We'll be in touch if there's any problems or follow-up questions.

[Xavrax]

Thank you for the confirmation and have fun with our SDK <3