diff options
Diffstat (limited to 'tools/lib/bpf/btf.c')
| -rw-r--r-- | tools/lib/bpf/btf.c | 44 |
1 files changed, 43 insertions, 1 deletions
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 2d270c560df3..1622a309f169 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -16,6 +16,11 @@ #define BTF_MAX_NR_TYPES 65535 +#define IS_MODIFIER(k) (((k) == BTF_KIND_TYPEDEF) || \ + ((k) == BTF_KIND_VOLATILE) || \ + ((k) == BTF_KIND_CONST) || \ + ((k) == BTF_KIND_RESTRICT)) + static struct btf_type btf_void; struct btf { @@ -269,6 +274,26 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) return nelems * size; } +int btf__resolve_type(const struct btf *btf, __u32 type_id) +{ + const struct btf_type *t; + int depth = 0; + + t = btf__type_by_id(btf, type_id); + while (depth < MAX_RESOLVE_DEPTH && + !btf_type_is_void_or_null(t) && + IS_MODIFIER(BTF_INFO_KIND(t->info))) { + type_id = t->type; + t = btf__type_by_id(btf, type_id); + depth++; + } + + if (depth == MAX_RESOLVE_DEPTH || btf_type_is_void_or_null(t)) + return -EINVAL; + + return type_id; +} + __s32 btf__find_by_name(const struct btf *btf, const char *type_name) { __u32 i; @@ -278,7 +303,7 @@ __s32 btf__find_by_name(const struct btf *btf, const char *type_name) for (i = 1; i <= btf->nr_types; i++) { const struct btf_type *t = btf->types[i]; - const char *name = btf_name_by_offset(btf, t->name_off); + const char *name = btf__name_by_offset(btf, t->name_off); if (name && !strcmp(type_name, name)) return i; @@ -368,3 +393,20 @@ int btf__fd(const struct btf *btf) { return btf->fd; } + +const char *btf__name_by_offset(const struct btf *btf, __u32 offset) +{ + if (offset < btf->hdr->str_len) + return &btf->strings[offset]; + else + return NULL; +} + +const struct btf_type *btf__type_by_id(const struct btf *btf, + __u32 type_id) +{ + if (type_id > btf->nr_types) + return NULL; + + return btf->types[type_id]; +} |