Let's introduce these for the following two reasons:
- Using them makes sure the parameter names match between declaration
and definition (if both use the corresponding macros).
- They make sure developers can't forget the _const_ and _pure_
attributes for the declarations.
This commit also includes some include sorting fixes
glibc defines AT_FDCWD as -100, but musl defines it as (-100).
In basic-forward.h, we also define AT_FDCWD as -100, hence musl's fcntl.h
conflicts with forward.h. This is for avoiding the conflict.
Let's not leak details from src/shared and src/libsystemd into
src/basic, even though you can't actually do anything useful with
just forward declarations from src/shared.
The sd-forward.h header is put in src/libsystemd/sd-common as we
don't have a directory for shared internal headers for libsystemd
yet.
Let's also rename forward.h to basic-forward.h to keep things
self-explanatory.
Yu Watanabe
Daan De Meyer
Mike Yuan