[pulseaudio-discuss] [PATCH] util: Fix pa_get_binary_name() on Debian/kFreeBSD

[Felipe Sateler]

On Mon, Aug 4, 2014 at 10:52 AM, Peter Meerwald <pmeerw at pmeerw.net> wrote:
>
>> > Debian GNU/kFreeBSD uses a FreeBSD kernel and GLIBC,
>> > it #defines __FreeBSD_kernel__, but not __FreeBSD__ nor __linux__
>> > Debian GNU/kFreeBSD does have a /proc/self/exe
>> >
>> > FreeBSD #defines __FreeBSD__ and __FreeBSD_kernel__
>> >
>> > problem reporte here:
>> > http://lists.freedesktop.org/archives/pulseaudio-discuss/2014-July/020998.html
>> >
>> > Signed-off-by: Peter Meerwald <pmeerw at pmeerw.net>
>> > ---
>> >  src/pulse/util.c | 2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> > diff --git a/src/pulse/util.c b/src/pulse/util.c
>> > index 50f90b8..42b160a 100644
>> > --- a/src/pulse/util.c
>> > +++ b/src/pulse/util.c
>> > @@ -193,7 +193,7 @@ char *pa_get_binary_name(char *s, size_t l) {
>> >      }
>> >  #endif
>> >
>> > -#ifdef __linux__
>> > +#if defined(__linux__) || defined(__FreeBSD_kernel__)
>>
>> If FreeBSD does not have /proc/self/exe, but defines
>> __FreeBSD_kernel__ then this check will pass, which I don't think is
>> intended.
>
> on FreeBSD it will call pa_readlink("/proc/self/exe") which will return
> NULL and then continue with the FreeBSD-specific code
>
>> Perhaps the check needs to be defined(__FreeBSD_kernel__) &&
>> !defined(__FreeBSD__)?
>
> would work as well, I prefer simpler #defines;
> defined(__FreeBSD_kernel__) && defined(__GLIBC__) should do as well
>
> one extra readlink() doesn't hurt

I just found out about this possibility[1]:

#include <dlfcn.h>
[...]
Dl_info DLInfo;
int err = dladdr(&main, &DLInfo);
if (err != 0) {
  // DLInfo.dli_fname has the executable name.
}

This should work on all glibc systems. I can prepare a patch if this
solution is acceptable too.

[1] https://www.gnu.org/software/hurd/hurd/translator/procfs/jkoenig/discussion.html#index7h1


-- 

Saludos,
Felipe Sateler