tests: Allow building without TIOCSTI

[emaste]

Summary

Posted for discussion. Some downstream projects (e.g. ElectroBSD) have removed the TIOCSTI #define and implementation; I'm curious what you think about #ifdefs like this to allow the test to build in this case.

Of course a downstream patch set could just include disconnecting the test, but this allows for a minimal change to remove TIOCSTI.

[markj]

I don't really understand--if we were to remove TIOCSTI, wouldn't that be done by removing the runtime implementation, rather than hiding the TIOCSTI symbol like this?

tests/sys/kern/tty/test_sti.c

329

[emaste]

In my tree I hid the sysctl to find consumers and confirm that the system works without it. The consumers are:

• clang sanitizers
• tcsh
• mail
• this test

mail and tcsh already have #ifndef TIOCSTI cases scattered throughout, presumably leftover from originally being portable (mail is not in /contrib though).

My thought was to allow downstream projects (e.g. ElectroBSD) maintain minimal diffs.

[markj]

In D50614#1311340, @emaste wrote:

In my tree I hid the sysctl to find consumers and confirm that the system works without it. The consumers are:

You mean the TIOCSTI definition was hidden?

• clang sanitizers
• tcsh
• mail
• this test

mail and tcsh already have #ifndef TIOCSTI cases scattered throughout, presumably leftover from originally being portable (mail is not in /contrib though).

My thought was to allow downstream projects (e.g. ElectroBSD) maintain minimal diffs.

If I understand correctly, you're not proposing to actually remove the definition of TIOCSTI, just to make it easier to compile the base system against headers that do not define it.

[emaste]

You mean the TIOCSTI definition was hidden?

Sorry, yes. The ioctl definition.