Re: [libvirt] [GSoC] Design ideas for implementing cleanup attribute

On Wed, 2018-05-23 at 18:05 +0200, Pavel Hrdina wrote: > I liked the way how GLib is solving the issue so we can simply use the > same approach since it looks reasonable. > > There would be three different macros that would be used to annotate > variable with attribute cleanup: > > VIR_AUTOFREE char *str = NULL; > > - this would call virFree on that variable > > VIR_AUTOPTR(virDomain) domain = NULL; > > - this would call registered free function on that variable > - to register the free function you would use: > > VIR_DEFINE_AUTOPTR_FUNC(virDomain, virDomainFree); > > VIR_AUTOCLEAR(virDomain) domain = { 0 }; > > - this would call registered clear function to free the content of > that structure > - to register that clear function you would use: > > VIR_DEFINE_AUTOCLEAR_FUNC(virDomain, virDomainClear); I assume you would get a compilation error when trying to eg. use VIR_AUTOCLEAR() with a type that doesn't have a clear function registered?

As for VIR_AUTOFREE() and VIR_AUTOPTR(), I'd very much prefer if we could have a single macro, since from the high-level point of view they're both doing the same thing, that is, freeing memory that was allocated on the heap.

However, I realize it might not be possible to register free functions for a native type without having to introduce something like typedef char * virString; thus causing massive churn. How does GLib deal with that?