From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vincent Hanquez <vincent.hanquez@eu.citrix.com>
Subject: Re: [PATCH 0 of 3] libxl: memory leaks
Date: Tue, 03 Aug 2010 14:37:56 +0100
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To: "Gianni Tedesco (3P)" <gianni.tedesco@citrix.com>
Cc: Ian Campbell <Ian.Campbell@eu.citrix.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 03/08/10 13:16, Gianni Tedesco (3P) wrote:
> I actually prefer explicit free's on the returned objects. That gives
> callers a lot more control. Have you seen Ians patch auto-generating
> that code? I think this approach combined with automatic-freeing of
> scratch data used in libxl calls is the best of both worlds.
>    
How much control do you actually need ?

In python you'ld have the approach:

my_function_xl_binded()
{
  fill_structure(&structure);
  CTX_INIT;
  do_xl_call(&structure);
  pyval= convert_to_python_values(&structure);
  CTX_FREE;
  return pyval;
}

in OCaml exactly the same.

how is that an improvement for python and ocaml bindings that you have 
to insert the right call in some functions to do some more freeing ?

It also save having to generate freeing code.

> I don't know about ocaml but assume it's trivial to call a libxl_*_free
> function when an object which encapsulates a libxl returned object is
> destroyed?
>    
it's possible and not very hard, it doesn't mean that should be done though.
I really like the braindead approch of after i called libxl_ctx_free, i 
don't have anything to do with memory by design. You're advocating for 
having to put the right call in the right functions in the place that 
need it.

-- 
Vincent