Re: [Qemu-devel] [PATCH 1/5] char: Add a QemuChrHandlers struct to initialise chardev handlers

[Blue Swirl]

On Wed, Jan 12, 2011 at 6:01 PM, Michael Roth <address@hidden> wrote:
> On 01/12/2011 12:07 AM, Amit Shah wrote:
>>
>> On (Tue) Jan 11 2011 [17:13:15], Blue Swirl wrote:
>>>>
>>>> +static QemuChrHandlers gdb_handlers = {
>>>> +    .fd_can_read = gdb_chr_can_receive,
>>>> +    .fd_read = gdb_chr_receive,
>>>> +    .fd_event = gdb_chr_event,
>>>> +};
>>>
>>> These structures should be const.
>>
>> Hm, I had that but looks like it got lost in some rebase.  Added again.
>>
>>>> @@ -190,15 +190,19 @@ void qemu_chr_send_event(CharDriverState *s, int
>>>> event)
>>>>         s->chr_send_event(s, event);
>>>>  }
>>>>
>>>> +static QemuChrHandlers null_handlers = {
>>>> +    /* All handlers are initialised to NULL */
>>>> +};
>>>> +
>>>>  void qemu_chr_add_handlers(CharDriverState *s,
>>>> -                           IOCanReadHandler *fd_can_read,
>>>> -                           IOReadHandler *fd_read,
>>>> -                           IOEventHandler *fd_event,
>>>> -                           void *opaque)
>>>> -{
>>>> -    s->chr_can_read = fd_can_read;
>>>> -    s->chr_read = fd_read;
>>>> -    s->chr_event = fd_event;
>>>> +                           QemuChrHandlers *handlers, void *opaque)
>>>> +{
>>>
>>> Here we could also check if (!s) and return if so. This would simplify
>>> the callers a bit.
>>
>> Simplified in what way?
>
> I assume for reducing the need to have to check s->chr != NULL everytime
> beforehand. It's safer and would save a lot on repetitive code as well.

Yes, that's what I meant.