2022-09-22 00:47:16

by Andrii Nakryiko

[permalink] [raw]
Subject: Re: [bpf-next v3 1/2] libbpf: Add pathname_concat() helper

On Sun, Sep 18, 2022 at 7:28 PM Wang Yufen <[email protected]> wrote:
>
> Move snprintf and len check to common helper pathname_concat() to make the
> code simpler.
>
> Signed-off-by: Wang Yufen <[email protected]>
> ---
> tools/lib/bpf/libbpf.c | 76 +++++++++++++++++++-------------------------------
> 1 file changed, 29 insertions(+), 47 deletions(-)
>

[...]

> @@ -8009,14 +8012,9 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
> char buf[PATH_MAX];
>
> if (path) {
> - int len;
> -
> - len = snprintf(buf, PATH_MAX, "%s/%s", path,
> - bpf_map__name(map));
> - if (len < 0)
> - return libbpf_err(-EINVAL);
> - else if (len >= PATH_MAX)
> - return libbpf_err(-ENAMETOOLONG);
> + err = pathname_concat(path, bpf_map__name(map), buf, PATH_MAX);
> + if (err)
> + return err;

also keep libbpf_err() as well, it sets errno properly

> sanitize_pin_path(buf);
> pin_path = buf;
> } else if (!map->pin_path) {
> @@ -8034,6 +8032,7 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
> int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
> {
> struct bpf_program *prog;
> + char buf[PATH_MAX];
> int err;
>
> if (!obj)

[...]