Re: [PATCH 1/8] tools lib bpf: add error functions

From: Wangnan (F)
Date: Tue Oct 18 2016 - 21:55:10 EST

On 2016/10/19 6:52, Joe Stringer wrote:
On 16 October 2016 at 14:18, Eric Leblond <eric@xxxxxxxxx> wrote:
The include of err.h is not explicitely needed in exported
functions and it was causing include conflict with some existing
code due to redefining some macros.

To fix this, let's have error handling functions provided by the
library. Furthermore this will allow user to have an homogeneous

Signed-off-by: Eric Leblond <eric@xxxxxxxxx>
Does it need to return the error like this or should we just fix up
the bpf_object__open() API to return errors in a simpler form?

There's already libbpf_set_print(...) for outputting errors, is it
reasonable to just change the library to return NULLs in error cases

Returning error code to caller so caller knows what happen.
Other subsystems in perf also do this.

Perf hides libbpf's error output (make it silent unless -v),
so it needs a way for receiving libbpf's error code.

I think this patch is good, decouple libbpf.h and kernel headers.

Thank you.