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

[wangyufen <wangyufen@huawei.com>]

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