Unify lengthof/string_lengthof -like macros

[am11]

• Move src/native/common to src/native/minipal
• Define _countof and _strcountof.
• Replace all _countof, lengthof, NumItems, ARRAY{_}SIZE like macros with _countof.
• Replace all lengthof and StrLen like macros with _strcountof.
  • Also replaced _countof() - 1 patterns to _strcountof() in few places.

In second commit, ran editor macro to cleanup trailing whitespaces in files touched by the first commit.

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[AraHaan]

What are the MENIPAL_* macros used here defined as?

[am11]

What are the MENIPAL_* macros used here defined as?

There were about 32 definitions of those macros repo-wide, this patch moves the definitions in a single place:

runtime/src/native/minipal/utils.h

Lines 7 to 10 in ad9e726

	#defineMINIPAL_LENGTHOF(arr) (sizeof(arr)/sizeof(arr[0]))
	// Number of characters in a string literal. Excludes terminating NULL.
	#defineMINIPAL_STRLEN(str) (MINIPAL_LENGTHOF(str) - 1)

[jkotas]

What is the most common name used for this macro in the universe? Would it look better to standardize on that name without any prefix?

[vargaz]

There is no common name i think, mono uses the name from glib.

[SingleAccretion]

Note that the Jit also uses an ArrLen function for this. I will say that if it were for me to decide, I'd replace all the uses of _countof in the Jit with it, but, heh, it is not :).

[am11]

I don't have strong opinions about the name (naming stuff is hard), so whatever is decided I'm fine with it; now that find & replace after this patch is much easier. ;)

Prefix convention (used heavily in mono) helps identifying where the macro or function definitions are coming from. Recently, we prefixed functions with minipal_. I followed the same here for macros to stay consistent that way.

[am11]

Renamed MINIPAL_{LENGTHOF, STRLEN} to _countof and _strcountof respectively.
CI test failures are unrelated to changes.

[vargaz]

That doesn't match the mono coding conventions and looks very much like some kind of compiler intrinsic.

[jkotas]

@vargaz What would be your preferred name?

[vargaz]

Not sure this particular macro needs to be unified between the runtimes, both of them already has their own version.

[jkotas]

I hope that we will share more code between the runtimes over time. I think it is important that we get the details like these unified to something reasonable. Do you have an opinion what should be the name to standardize on in the code shared between runtimes for this one?

[vargaz]

Imho the problem is that the runtimes have different coding conventions, so not sure a macro name can fit both equally well. I'd prefer the traditional uppercase macro naming style.

[am11]

src/native/eventpipe is another example of code shared between runtimes, where we have function, as well as the macro names prefixed and macros are upper cased. coreclr uses many different conventions (prefix, no prefix, upper, lower, mixed casing) for macros so there is no problem in changing it to whichever name is suitable.

[jkotas]

I'd prefer the traditional uppercase macro naming style.

Would ARRAY_SIZE work?

[jkotas]

Based on the feedback, here is my proposal to land this PR:

• Rename _countof/_strcountof to ARRAY_SIZE and STRING_LENGTH. I think it is reasonable convention to have macros in all caps and I agree that _countof looks more like a compiler intrinsic.
• Keep using G_N_ELEMENTS in mono since it is used fairly consistently there and follows the Mono coding style.

@am11 If there is no push back in next two days, could you please implement these change? I am sorry about the back and forth, and thank you for your work on various cleanups!

[vargaz]

Sounds good

[jkotas]

Thank you!