Re: [Qemu-devel] [PATCH v2] ioport: Fix duplicated code

[Luiz Capitulino <lcapitulino@redhat.com>]

On Fri, 19 Nov 2010 19:50:10 -0600
Anthony Liguori <anthony@codemonkey.ws> wrote:

> On 11/11/2010 08:03 AM, Luiz Capitulino wrote:
> > Functions register_ioport_read() and register_ioport_write() are almost
> > identical, the only difference is that they write to different arrays.
> >
> > Introduce register_ioport_rw() to handle this difference and change both
> > functions to use it instead of duplicating code.
> >
> > Signed-off-by: Luiz Capitulino<lcapitulino@redhat.com>
> >    
> 
> While it make take some scripting, let's do a global query/replace.
> 
> Having two interfaces where one is only scarely used hurts code 
> readability.  We need to do the janitorial work when changing interfaces 
> like this.

The goal of this patch was just to make register_ioport_read() and
register_ioport_write() use common code, what janitorial work should
we do?

Export register_ioport_rw() and change drivers to use it, instead of
calling register_ioport_read() and register_ioport_write()?

>
> Regards,
> 
> Anthony Liguori
> 
> > ---
> >
> > v2: Fix error messages and make register_ioport_rw() register both handlers
> >      at the same call
> >
> >   ioport.c |   37 ++++++++++++++++++-------------------
> >   1 files changed, 18 insertions(+), 19 deletions(-)
> >
> > diff --git a/ioport.c b/ioport.c
> > index ec3dc65..4560973 100644
> > --- a/ioport.c
> > +++ b/ioport.c
> > @@ -137,41 +137,40 @@ static int ioport_bsize(int size, int *bsize)
> >   }
> >
> >   /* size is the word size in byte */
> > -int register_ioport_read(pio_addr_t start, int length, int size,
> > -                         IOPortReadFunc *func, void *opaque)
> > +static int register_ioport_rw(pio_addr_t start, int length, int size,
> > +                              IOPortReadFunc *read_func,
> > +                              IOPortWriteFunc *write_func, void *opaque)
> >   {
> >       int i, bsize;
> >
> >       if (ioport_bsize(size,&bsize)) {
> > -        hw_error("register_ioport_read: invalid size");
> > +        hw_error("register_ioport_rw: invalid size");
> >           return -1;
> >       }
> >       for(i = start; i<  start + length; i += size) {
> > -        ioport_read_table[bsize][i] = func;
> > +        if (read_func) {
> > +            ioport_read_table[bsize][i] = read_func;
> > +        }
> > +        if (write_func) {
> > +            ioport_write_table[bsize][i] = write_func;
> > +        }
> >           if (ioport_opaque[i] != NULL&&  ioport_opaque[i] != opaque)
> > -            hw_error("register_ioport_read: invalid opaque");
> > +            hw_error("register_ioport_rw: invalid opaque");
> >           ioport_opaque[i] = opaque;
> >       }
> >       return 0;
> >   }
> >
> > -/* size is the word size in byte */
> > +int register_ioport_read(pio_addr_t start, int length, int size,
> > +                         IOPortReadFunc *func, void *opaque)
> > +{
> > +    return register_ioport_rw(start, length, size, func, NULL, opaque);
> > +}
> > +
> >   int register_ioport_write(pio_addr_t start, int length, int size,
> >                             IOPortWriteFunc *func, void *opaque)
> >   {
> > -    int i, bsize;
> > -
> > -    if (ioport_bsize(size,&bsize)) {
> > -        hw_error("register_ioport_write: invalid size");
> > -        return -1;
> > -    }
> > -    for(i = start; i<  start + length; i += size) {
> > -        ioport_write_table[bsize][i] = func;
> > -        if (ioport_opaque[i] != NULL&&  ioport_opaque[i] != opaque)
> > -            hw_error("register_ioport_write: invalid opaque");
> > -        ioport_opaque[i] = opaque;
> > -    }
> > -    return 0;
> > +    return register_ioport_rw(start, length, size, NULL, func, opaque);
> >   }
> >
> >   void isa_unassign_ioport(pio_addr_t start, int length)
> >    
>