Reference counting of `InitAPI`

[jmklix]

Describe the feature

Provide a mechanism to prevent the sdk from breaking when InitAPI gets called when it has already been initialized.

Related issues/discussions:

• Is there a way to know Aws::InitAPI has been called? #2406
• Multiple calls to InitAPI() / ShutdownAPI()? #456

Use Case

If code is being used in a library then there is currently no way for the library to know if InitAPI has already been called.

Proposed Solution

This will not/should not be RAII.

Using locks and reference counting this would allow multiple calls of InitAPI. Changes need to be make on this sdk and with the CRT

Other Information

Community Note

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Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

[WolfgangVogl]

Just to clearify this for me: Calling InitAPI multiple times on a machine is okay as long as you don't do it inside the same application? Or has such a reference count to be system wide?

[jmklix]

Just to clearify this for me: Calling InitAPI multiple times on a machine is okay as long as you don't do it inside the same application? Or has such a reference count to be system wide?

Yes, that should be fine as long as the programs aren't sharing memory

[jeking3]

You can also handle the error result when it is already initialized, and ignore it.

[jmklix]

03036e4

[johnkerl]

Does anyone know why #2699 triggers only on MacOS? We see this only on MacOS, not Linux, and I'd like to understand what's Mac-specific here ...

[SergeyRyabinin]

Does anyone know why #2699 triggers only on MacOS? We see this only on MacOS, not Linux, and I'd like to understand what's Mac-specific here ...

The issue linked is about the case when the Client outlives the InitAPI{}ShutdownAPI scope.
This is a case of not following SDK basic-use documentation, however, I agree that the SDK API is not friendly, that's why, to prevent such kind of error, a client lifetime check has been added in #2515

The reason was failnig only on mac is due to the nature of undefined behavior, it may be different between different platforms and compilers.

Anyway, this issue is prevented from happening from different angles now.