Re: [Qemu-devel] [PATCH 3/3] configure: add '--disable-cocoa' switch

[Andreas Färber]

Am 17.01.2012 00:46, schrieb Andrzej Zaborowski:
> On 14 January 2012 01:42, Andreas Färber <address@hidden> wrote:
>> Am 08.12.2011 01:41, schrieb Andreas Färber:
>>> Am 10.11.2011 19:40, schrieb Pavel Borzenkov:
>>>> When SDL support is disabled, there is no way to build QEMU without
>>>> Cocoa support on MacOS X. This patch adds '--disable-cocoa' switch and
>>>> allows to build QEMU without both SDL and Cocoa frontends.
>>>>
>>>> Signed-off-by: Pavel Borzenkov <address@hidden>
>>>> ---
>>>>  configure |    7 ++++++-
>>>>  1 files changed, 6 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/configure b/configure
>>>> index 401d9a6..4720bb2 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -670,6 +670,8 @@ for opt do
>>>>    ;;
>>>>    --enable-profiler) profiler="yes"
>>>>    ;;
>>>> +  --disable-cocoa) cocoa="no"
>>>> +  ;;
>>>>    --enable-cocoa)
>>>>        cocoa="yes" ;
>>>>        sdl="no" ;
>>>
>>> Tested-by: Andreas Färber <address@hidden>
>>>
>>>> @@ -980,7 +982,10 @@ echo "  --disable-sdl            disable SDL"
>>>>  echo "  --enable-sdl             enable SDL"
>>>>  echo "  --disable-vnc            disable VNC"
>>>>  echo "  --enable-vnc             enable VNC"
>>>> -echo "  --enable-cocoa           enable COCOA (Mac OS X only)"
>>>> +if test "$darwin" = "yes" ; then
>>>> +    echo "  --disable-cocoa          disable COCOA"
>>>> +    echo "  --enable-cocoa           enable COCOA (default)"
>>>> +fi
>>>>  echo "  --audio-drv-list=LIST    set audio drivers list:"
>>>>  echo "                           Available drivers: 
>>>> $audio_possible_drivers"
>>>>  echo "  --audio-card-list=LIST   set list of emulated audio cards 
>>>> [$audio_card_list]"
>>>
>>> I see no prior art of any conditional help output in configure. Anthony?
>>> Andrzej?
>>
>> Ping? Should we keep command line options a flat list with comments on
>> applicability or start introducing tests like above?
>>
>> Me, I'd prefer not doing this since the switch cases above don't check.
> 
> Perhaps --diable-cocoa should be allowed on any platform.  You're
> right we don't have such checks now, but then it's hard to see
> downsides of doing them, so I'm quite ambivalent.
> 
> I still don't see the purpose of the following test in configure though:
>       if test "$cocoa" = "no" ; then
>         sdl=yes
>       fi

The reason is that SDL and Cocoa must not both be detected due to the
way it is handled in vl.c. Given that Cocoa is enabled by default, SDL
must not be detected in that case. If Cocoa is disabled, then detecting
SDL is fine of course.

The alternative would be to check for SDL and, if present, disable
Cocoa. Still collides with Pavel's patch though - we need to sort out
how to merge them.

> With it in place and no --disable-cocoa there's no way to compile SDL.

>  --enable-cocoa is also broken as fas as I can tell.

I've been using it for historic reasons without noticeable problems.

Andreas