Re: EV_SET() better C++ compat with alternative implementations

[Valery Ushakov <uwe%stderr.spb.ru@localhost>]

On Wed, Aug 14, 2019 at 06:06:18 +0300, Valery Ushakov wrote:

> static inline void
> EV_SET_(struct kevent *_kevp, uintptr_t _ident, uint32_t _filter,
> 	uint32_t _flags, uint32_t _fflags, int64_t _data,
>         uintptr_t _udata)
> {
> 	_kevp->ident = _ident;
> 	_kevp->filter = _filter;
> 	_kevp->flags = _flags;
> 	_kevp->fflags = _fflags;
> 	_kevp->data = _data;
> 	_kevp->udata = _udata;
> }

Oops, s/uintptr_t/intptr_t/

And this is actually already defined for C, so we need to just provide
the templates.

template <typename _U>
static inline void __always_inline
EV_SET(struct kevent *_kevp, uintptr_t _ident, uint32_t _filter,
       uint32_t _flags, uint32_t _fflags, int64_t _data,
       _U _udata)
{
    EV_SET_(_kevp, _ident, _filter, _flags, _fflags, _data,
	    static_cast<intptr_t>(_udata));
}

/* specialize for std::nullptr_t */
template <>
inline void __always_inline
EV_SET(struct kevent *_kevp, uintptr_t _ident, uint32_t _filter,
       uint32_t _flags, uint32_t _fflags, int64_t _data,
       decltype(nullptr) _udata __unused)
{
    EV_SET_(_kevp, _ident, _filter, _flags, _fflags, _data, 0);
}


-uwe