Fix re-sending config data

[cookie777]

Issue

The current ble connection freezes if you try to connect (establish the session) to the device again.

Details

• The first time you use connect function in. the ESPDevice, it works.
• However, if the completion status is error and if we try to use this function again, the app will freeze.

espDevice.connect(delegate: self) { status in
}

Reason

The DispatchSemaphore doesn't call signal() when it catches errors.

Details

• Whenever we call connect or sendData from ESPDevice, internally we all func SendConfigData
• This function locks the process by transportToken.wait()and releases it when the process finishes.
• However, transportToken.signal() is not called when the process ends with error.
  • When we call espressifPeripheral.writeValue in the function, delegate functions didWriteValueFor or didUpdateValueFor is called.
  • When it catches errors, it completes with only handler.(without signal())

        guard error == nil else {
            currentRequestCompletionHandler?(nil, error)
            return
        }

Solution

Set transportToken.signal() in delegate functions didWriteValueFor and didUpdateValueFor when it catches error.

        guard error == nil else {
            transportToken.signal() // This is needed to release Semaphore
            currentRequestCompletionHandler?(nil, error)
            return
        }

[CLAassistant]

All committers have signed the CLA.

[vikas-chandra-mnnit]

Hi @cookie777, we have removed DispatchSemaphore in our latest version of SDK I.e. 2.0.15. However, if you think there is some scenario in which use of the Semaphore is essential then do let us know so that we can quickly revert our changes and merge your PR for the next build.

[cookie777]

Hello @vikas-chandra-mnnit .
I'm happy with removing DispatchSemaphore 👍 Thank you for your support!

[puneet-arora15]

@cookie777 Did the issue get resolved for you with the latest SDK ? As I'm still seeing this issue in the app

[cookie777]

I havn't faced this issue after all transportToken.signal() are removed from the code.