Re: [Qemu-devel] [PATCH 1/3] Check for Linux USBFS in configure

[Laurent Vivier]

Le 19/09/2018 à 15:39, Laurent Vivier a écrit :
> Le 19/09/2018 à 10:04, Cortland Tölva a écrit :
>> In preparation for adding user mode emulation support for the
>> Linux usbfs interface, check for its kernel header.
>>
>> Signed-off-by: Cortland Tölva <address@hidden>
>> ---
>>  configure | 21 ++++++++++++++++++++-
>>  1 file changed, 20 insertions(+), 1 deletion(-)
>>
>> diff --git a/configure b/configure
>> index 58862d2ae8..5d36f45442 100755
>> --- a/configure
>> +++ b/configure
>> @@ -4235,7 +4235,23 @@ if compile_prog "" "" ; then
>>    memfd=yes
>>  fi
>>  
>> -
>> +# check for usbfs
>> +have_usbfs=no
>> +if test "$linux_user" = "yes"; then
>> +  cat > $TMPC << EOF
>> +#include <linux/usbdevice_fs.h>
>> +int main(void) {
>> +#if !defined(USBDEVFS_URB_TYPE_CONTROL)
>> +#error Missing usbdevfs defintions.
> 
> s/defintions./definitions/
> 
>> +#else
>> +    return 0;
>> +#endif
>> +}
>> +EOF
>> +  if compile_prog "" "" ; then
> 
> As you don't check for any lib API, I think you don't need the ld stage,
> so you can use compile_object instead (and you don't need the main body)

BTW, I think it's enough to do a "check_include linux/usbdevice_fs.h" as
the symbol has no special meaning and you only need to know if the file
is present to include it.

Thanks,
Laurent