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?
--
Andrea Bolognani / Red Hat / Virtualization