[Libguestfs] [PATCH v2] customize/perl_edit-c.c: Don't use internal APIs.

[Richard W.M. Jones]

On Thu, Apr 14, 2016 at 03:33:25PM +0200, Pino Toscano wrote:
> On Tuesday 12 April 2016 08:41:37 Richard W.M. Jones wrote:
> > We can now use the Guestfs.c_pointer method to access the underlying
> > guestfs_h *.  So no need to use internal APIs for this.
> > ---
> >  customize/perl_edit-c.c | 18 ++++++------------
> >  customize/perl_edit.ml  | 10 ++++++++--
> >  2 files changed, 14 insertions(+), 14 deletions(-)
> > 
> > diff --git a/customize/perl_edit-c.c b/customize/perl_edit-c.c
> > index 753d990..7191bef 100644
> > --- a/customize/perl_edit-c.c
> > +++ b/customize/perl_edit-c.c
> > @@ -25,30 +25,24 @@
> >  #include <caml/alloc.h>
> >  #include <caml/memory.h>
> >  #include <caml/mlvalues.h>
> > +#include <caml/fail.h>
> >  
> >  #include "file-edit.h"
> >  
> > -/**
> > - * We try to reuse the internals of the OCaml binding (for extracting
> > - * the guestfs handle, and raising errors); hopefully this should be safe,
> > - * as long as it's kept internal within the libguestfs sources.
> > - */
> > -#include "../ocaml/guestfs-c.h"
> > -
> >  #pragma GCC diagnostic ignored "-Wmissing-prototypes"
> >  
> >  value
> > -virt_customize_edit_file_perl (value verbosev, value gv, value filev,
> > -                               value exprv)
> > +virt_customize_edit_file_perl (value verbosev, value gv, value gpv,
> > +                               value filev, value exprv)
> >  {
> > -  CAMLparam4 (verbosev, gv, filev, exprv);
> > +  CAMLparam5 (verbosev, gv, gpv, filev, exprv);
> >    int r;
> > -  guestfs_h *g = Guestfs_val (gv);
> > +  guestfs_h *g = (guestfs_h *) Int64_val (gpv);
> 
> This causes warnings on 32bit platforms though:
> 
> perl_edit-c.c: In function 'virt_customize_edit_file_perl':
> perl_edit-c.c:40:18: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>    guestfs_h *g = (guestfs_h *) Int64_val (gpv);
>                   ^
> What about the following patch?
> 
> Subject: [PATCH] customize: cast value to intptr_t for pointer usage
> 
> Cast a Int64 OCaml value to intptr_t before casting it to a pointer, so
> this avoids warnings about casting an int to pointer.
> 
> Fixes commit 80a13b7216340b2bee437c39db2375b61804e133.
> ---
>  customize/perl_edit-c.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/customize/perl_edit-c.c b/customize/perl_edit-c.c
> index 7191bef..9558d07 100644
> --- a/customize/perl_edit-c.c
> +++ b/customize/perl_edit-c.c
> @@ -37,7 +37,7 @@ virt_customize_edit_file_perl (value verbosev, value gv, value gpv,
>  {
>    CAMLparam5 (verbosev, gv, gpv, filev, exprv);
>    int r;
> -  guestfs_h *g = (guestfs_h *) Int64_val (gpv);
> +  guestfs_h *g = (guestfs_h *) (intptr_t) Int64_val (gpv);
> 
>    r = edit_file_perl (g, String_val (filev), String_val (exprv), NULL,
>                        Bool_val (verbosev));

ACK.

Rich.

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