Dns unittest preparation

[michalpasztamobica]

Description

While working on unittests for nsapi_dns I noticed two things:

1. unique_id is cast from int to void * type and is always assumed to be 32-bit. This may be true for microcontrollers, but unittests are running on 64-bit machines (checked this with INFRA team). I therefore changed the type of unique_id to a more arch-independent intptr_t. This will still be a 32-bit variable for microcontrollers.
2. nsapi_dns_query_async_cancel had a different definition and implementation. Once the function was put to use the linker was unable to connect the two and gave errors. Unifying the header fixes the issue.

The unittests themselves will be put into a separate PR, in order not to mix code fixes and test updates.

Pull request type

[x] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Docs update
[ ] Test update
[ ] Breaking change

Reviewers

@AnttiKauppila
@tymoteuszblochmobica

[ciarmcom]

@michalpasztamobica, thank you for your changes.
@AnttiKauppila @tymoteuszblochmobica @ARMmbed/mbed-os-ipcore @ARMmbed/mbed-os-maintainers please review.

[0xc0170]

Dependency above ^^

[michalpasztamobica]

@0xc0170 , sorry, I used wrong wording. THIS is the PR we need to merge first.
#11755 has tests, which will not compile without this fix.

[0xc0170]

I started initial test while we complete the review

[mbed-ci]

Test run: FAILED

Summary: 3 of 4 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_build-ARM
• jenkins-ci/mbed-os-ci_build-GCC_ARM
• jenkins-ci/mbed-os-ci_build-IAR

[michalpasztamobica]

@0xc0170, a few targets (DISCO_L475, GR_LYCHEE and NUMAKER_PFM_NUC472) failed with:

[2019-10-28T17:59:04.539Z] [mbed] ERROR: A program with name "mbed-os" already exists.

I don't think this is related to my changes?
EDIT: rerunning gave me the same problem.

[0xc0170]

I restarted it again

[mbed-ci]

Test run: FAILED

Summary: 1 of 11 test jobs failed
Build number : 2
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_exporter

[michalpasztamobica]

Build claims everything passed, but CI indicates exporter failure. @0xc0170 , can you please check? It looks like something unrelated to the PR changes...

[0xc0170]

Exporters were restarted and all good, I might have missed to post "restarting"

[0xc0170]

One more review from @ARMmbed/mbed-os-ipcore needed here

[michalpasztamobica]

@AnttiKauppila , would you have a minute to review?

[adbridge]

This is on top of #11535 which is currently scheduled for post 5.15 (TBC)