Hi
On Wed, Sep 8, 2021 at 4:33 PM Markus Armbruster <arm...@redhat.com> wrote:
> marcandre.lur...@redhat.com writes:
>
> > From: Marc-André Lureau <marcandre.lur...@redhat.com>
> >
> > Generate Rust #[cfg(...)] guards from QAPI 'if' conditions.
> >
> > Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> > ---
> > scripts/qapi/common.py | 16 ++++++++++++++++
> > scripts/qapi/schema.py | 4 ++++
> > 2 files changed, 20 insertions(+)
> >
> > diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
> > index 5f8f76e5b2..6d22c66391 100644
> > --- a/scripts/qapi/common.py
> > +++ b/scripts/qapi/common.py
> > @@ -201,6 +201,22 @@ def guardend(name: str) -> str:
> > name=c_fname(name).upper())
> >
> >
> > +def rsgen_ifcond(ifcond: Union[str, Dict[str, Any]]) -> str:
> > +
> > + def cfg(ifcond: Union[str, Dict[str, Any]]):
> > + if isinstance(ifcond, str):
> > + return ifcond
> > + if isinstance(ifcond, list):
> > + return ', '.join([cfg(c) for c in ifcond])
> > + oper, operands = next(iter(ifcond.items()))
> > + operands = cfg(operands)
> > + return f'{oper}({operands})'
> > +
> > + if not ifcond:
> > + return ''
> > + return '#[cfg(%s)]' % cfg(ifcond)
> > +
> > +
> > def gen_ifcond(ifcond: Optional[Union[str, Dict[str, Any]]],
> > cond_fmt: str, not_fmt: str,
> > all_operator: str, any_operator: str) -> str:
>
> Can we generalize gen_ifcond() to work for rsgen_ifcond(), too?
>
>
Not elegantly, I am afraid. The logic of gen_ifcond() is based around the
distinct prefix vs infix handling. In contrast, Rust cfg are all infix. As
you can see from the code above, it is quite straightforward. Reusing
gen_ifcond() would make it quite convoluted.
> > diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
> > index 6455a8f425..c61f35e13f 100644
> > --- a/scripts/qapi/schema.py
> > +++ b/scripts/qapi/schema.py
> > @@ -26,6 +26,7 @@
> > docgen_ifcond,
> > gen_endif,
> > gen_if,
> > + rsgen_ifcond,
> > )
> > from .error import QAPIError, QAPISemError, QAPISourceError
> > from .expr import check_exprs
> > @@ -48,6 +49,9 @@ def gen_endif(self):
> > def docgen(self):
> > return docgen_ifcond(self.ifcond)
> >
> > + def rsgen(self):
> > + return rsgen_ifcond(self.ifcond)
> > +
> > def is_present(self):
> > return bool(self.ifcond)
>
>
