bpftool: Print the enum's name instead of value

This patch prints the enum's name if there is one found in
the array of btf_enum.

The commit 9eea984979 ("bpf: fix BTF verification of enums")
has details about an enum could have any power-of-2 size (up to 8 bytes).
This patch also takes this chance to accommodate these non 4 byte
enums.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171637.128862-1-kafai@fb.com
This commit is contained in:
Martin KaFai Lau 2020-03-18 10:16:37 -07:00 committed by Daniel Borkmann
parent 90ceddcb49
commit ca7e6e45d1

View File

@ -43,9 +43,42 @@ static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id,
return btf_dumper_do_type(d, actual_type_id, bit_offset, data);
}
static void btf_dumper_enum(const void *data, json_writer_t *jw)
static int btf_dumper_enum(const struct btf_dumper *d,
const struct btf_type *t,
const void *data)
{
jsonw_printf(jw, "%d", *(int *)data);
const struct btf_enum *enums = btf_enum(t);
__s64 value;
__u16 i;
switch (t->size) {
case 8:
value = *(__s64 *)data;
break;
case 4:
value = *(__s32 *)data;
break;
case 2:
value = *(__s16 *)data;
break;
case 1:
value = *(__s8 *)data;
break;
default:
return -EINVAL;
}
for (i = 0; i < btf_vlen(t); i++) {
if (value == enums[i].val) {
jsonw_string(d->jw,
btf__name_by_offset(d->btf,
enums[i].name_off));
return 0;
}
}
jsonw_int(d->jw, value);
return 0;
}
static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id,
@ -366,8 +399,7 @@ static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
case BTF_KIND_ARRAY:
return btf_dumper_array(d, type_id, data);
case BTF_KIND_ENUM:
btf_dumper_enum(data, d->jw);
return 0;
return btf_dumper_enum(d, t, data);
case BTF_KIND_PTR:
btf_dumper_ptr(data, d->jw, d->is_plain_text);
return 0;