modem: backend: tty: Support building with any C library #101355
+58
−16
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Ensure we call into the host C library open/close/read/write independently of which embedded C library the code is built with.
We do this by:
a) Using the native simulator nsi_host* trampolines when we just want to call straight into the host libC.
b) Building in the native_simulator runner context (and therefore with the host C library) two functions which we call from the embedded side.
&
tests/subsys/modem/backends/tty: Ensure it is built with proper C lib
This test itself (not the code under test) needs to be build with the host C library as it calls into its open/close/read/write APIs.
So let's ensure we build it with it, independently of what the default C library may be.
Note there is minor functional change, the code before would block during polls during 100ms and then wait 100ms until the next poll. Now it does not block during polls (it just checks and returns immediately) and then waits 100ms.