Nick Terrell 8bf699aa59 [build] Add support for ASM files in Make + CMake
* Extract out common portion of `lib/Makefile` into `lib/libzstd.mk`.
  Most relevantly, the way we find library files.
* Use `lib/libzstd.mk` in the other Makefiles instead of repeating the
  same code.
* Add a test `tests/test-variants.sh` that checks that the builds of
  `make -C programs allVariants` are correct, and run it in Actions.
* Adds support for ASM files in the CMake build.

The Meson build is not updated because it lists every file in zstd,
and supports ASM off the bat, so the Huffman ASM commit will just add
the ASM file to the list.

The Visual Studios build is not updated because I'm not adding ASM
support to Visual Studios yet.
2021-09-17 14:13:53 -07:00
..
2018-10-03 18:42:44 -07:00
2019-09-14 21:10:42 +03:00

Cmake contributions

Contributions to the cmake build configurations are welcome. Please use case sensitivity that matches modern (ie. cmake version 2.6 and above) conventions of using lower-case for commands, and upper-case for variables.

How to build

As cmake doesn't support command like cmake clean, it's recommended to perform a "out of source build". To do this, you can create a new directory and build in it:

cd build/cmake
mkdir builddir
cd builddir
cmake ..
make

Then you can clean all cmake caches by simply delete the new directory:

rm -rf build/cmake/builddir

And of course, you can directly build in build/cmake:

cd build/cmake
cmake
make

To show cmake build options, you can:

cd build/cmake/builddir
cmake -LH ..

Bool options can be set to ON/OFF with -D[option]=[ON/OFF]. You can configure cmake options like this:

cd build/cmake/builddir
cmake -DZSTD_BUILD_TESTS=ON -DZSTD_LEGACY_SUPPORT=ON ..
make

referring

Looking for a 'cmake clean' command to clear up CMake output

CMake Style Recommendations

Indent all code correctly, i.e. the body of

  • if/else/endif
  • foreach/endforeach
  • while/endwhile
  • macro/endmacro
  • function/endfunction

Use spaces for indenting, 2, 3 or 4 spaces preferably. Use the same amount of spaces for indenting as is used in the rest of the file. Do not use tabs.

Upper/lower casing

Most important: use consistent upper- or lowercasing within one file !

In general, the all-lowercase style is preferred.

So, this is recommended:

add_executable(foo foo.c)

These forms are discouraged

ADD_EXECUTABLE(bar bar.c)
Add_Executable(hello hello.c)
aDd_ExEcUtAbLe(blub blub.c)

End commands

To make the code easier to read, use empty commands for endforeach(), endif(), endfunction(), endmacro() and endwhile(). Also, use empty else() commands.

For example, do this:

if(FOOVAR)
   some_command(...)
else()
   another_command(...)
endif()

and not this:

if(BARVAR)
   some_other_command(...)
endif(BARVAR)

Other resources for best practices

https://cmake.org/cmake/help/latest/manual/cmake-developer.7.html#modules