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

wangyufen <wangyufen@xxxxxxxxxx> · Thu, 22 Sep 2022 09:50:54 +0800





在 2022/9/22 8:41, Andrii Nakryiko 写道:
On Sun, Sep 18, 2022 at 7:28 PM Wang Yufen <wangyufen@xxxxxxxxxx> wrote:
Move snprintf and len check to common helper pathname_concat() to make the
code simpler.

Signed-off-by: Wang Yufen <wangyufen@xxxxxxxxxx>
---
  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)
[...]


Thanks for your comments， will send v4.








