From ca7e6e45d108f5712aec4407e6c757af59d43d0f Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Wed, 18 Mar 2020 10:16:37 -0700 Subject: [PATCH] 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 9eea98497951 ("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 Signed-off-by: Daniel Borkmann Acked-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200318171637.128862-1-kafai@fb.com --- tools/bpf/bpftool/btf_dumper.c | 40 ++++++++++++++++++++++++++++++---- 1 file changed, 36 insertions(+), 4 deletions(-) diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c index 01cc52b834fa..e86e240da4df 100644 --- a/tools/bpf/bpftool/btf_dumper.c +++ b/tools/bpf/bpftool/btf_dumper.c @@ -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;