Add lots of frequently used helpers that simplify working with BTF
types.
Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
---
tools/lib/bpf/btf.h | 176 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 176 insertions(+)
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 88a52ae56fc6..63c939b71efe 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -5,6 +5,7 @@
#define __LIBBPF_BTF_H
#include <stdarg.h>
+#include <linux/btf.h>
#include <linux/types.h>
#ifdef __cplusplus
@@ -120,6 +121,181 @@ LIBBPF_API void btf_dump__free(struct btf_dump *d);
LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id);
+/*
+ * A set of helpers for easier BTF types handling
+ */
+static inline __u16 btf_kind(const struct btf_type *t)
+{
+ return BTF_INFO_KIND(t->info);
+}
+
+static inline __u16 btf_vlen(const struct btf_type *t)
+{
+ return BTF_INFO_VLEN(t->info);
+}
+
+static inline bool btf_kflag(const struct btf_type *t)
+{
+ return BTF_INFO_KFLAG(t->info);
+}
+
+static inline bool btf_is_int(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_INT;
+}
+
+static inline bool btf_is_ptr(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_PTR;
+}
+
+static inline bool btf_is_array(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_ARRAY;
+}
+
+static inline bool btf_is_struct(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_STRUCT;
+}
+
+static inline bool btf_is_union(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_UNION;
+}
+
+static inline bool btf_is_composite(const struct btf_type *t)
+{
+ __u16 kind = btf_kind(t);
+
+ return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
+}
+
+static inline bool btf_is_enum(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_ENUM;
+}
+
+static inline bool btf_is_fwd(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_FWD;
+}
+
+static inline bool btf_is_typedef(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_TYPEDEF;
+}
+
+static inline bool btf_is_volatile(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_VOLATILE;
+}
+
+static inline bool btf_is_const(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_CONST;
+}
+
+static inline bool btf_is_restrict(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_RESTRICT;
+}
+
+static inline bool btf_is_mod(const struct btf_type *t)
+{
+ __u16 kind = btf_kind(t);
+
+ return kind == BTF_KIND_VOLATILE ||
+ kind == BTF_KIND_CONST ||
+ kind == BTF_KIND_RESTRICT;
+}
+
+static inline bool btf_is_func(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_FUNC;
+}
+
+static inline bool btf_is_func_proto(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_FUNC_PROTO;
+}
+
+static inline bool btf_is_var(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_VAR;
+}
+
+static inline bool btf_is_datasec(const struct btf_type *t)
+{
+ return btf_kind(t) == BTF_KIND_DATASEC;
+}
+
+static inline __u8 btf_int_encoding(const struct btf_type *t)
+{
+ return BTF_INT_ENCODING(*(__u32 *)(t + 1));
+}
+
+static inline __u8 btf_int_offset(const struct btf_type *t)
+{
+ return BTF_INT_OFFSET(*(__u32 *)(t + 1));
+}
+
+static inline __u8 btf_int_bits(const struct btf_type *t)
+{
+ return BTF_INT_BITS(*(__u32 *)(t + 1));
+}
+
+static inline const struct btf_array *btf_array(const struct btf_type *t)
+{
+ return (const struct btf_array *)(t + 1);
+}
+
+static inline const struct btf_enum *btf_enum(const struct btf_type *t)
+{
+ return (const struct btf_enum *)(t + 1);
+}
+
+static inline const struct btf_member *btf_members(const struct btf_type *t)
+{
+ return (const struct btf_member *)(t + 1);
+}
+
+/* get bit offset of a member with specified index */
+static inline const __u32 btf_member_bit_offset(const struct btf_type *t,
+ __u32 member_idx)
+{
+ const struct btf_member *m = btf_members(t) + member_idx;
+ bool kflag = btf_kflag(t);
+
+ return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset;
+}
+/* get bitfield size of a member, assuming t is BTF_KIND_STRUCT or
+ * BTF_KIND_UNION. If member is not a bitfield, zero is returned. */
+static inline const __u32 btf_member_bitfield_size(const struct btf_type *t,
+ __u32 member_idx)
+{
+ const struct btf_member *m = btf_members(t) + member_idx;
+ bool kflag = btf_kflag(t);
+
+ return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0;
+}
+
+static inline const struct btf_param *btf_params(const struct btf_type *t)
+{
+ return (const struct btf_param *)(t + 1);
+}
+
+static inline const struct btf_var *btf_var(const struct btf_type *t)
+{
+ return (const struct btf_var *)(t + 1);
+}
+
+static inline const struct btf_var_secinfo *
+btf_var_secinfos(const struct btf_type *t)
+{
+ return (const struct btf_var_secinfo *)(t + 1);
+}
+
#ifdef __cplusplus
} /* extern "C" */
#endif
--
2.17.1
