libbpf: Expose bpf_core_{add,free}_cands() to bpftool

Expose bpf_core_add_cands() and bpf_core_free_cands() to handle
candidates list.

Signed-off-by: Mauricio Vásquez <[email protected]>
Signed-off-by: Rafael David Tinoco <[email protected]>
Signed-off-by: Lorenzo Fontana <[email protected]>
Signed-off-by: Leonardo Di Donato <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

Author: mauriciovasquezbernal

tools/lib/bpf/libbpf.c

@@ -5192,18 +5192,21 @@ size_t bpf_core_essential_name_len(const char *name)
 	return n;
 }
 
-static void bpf_core_free_cands(struct bpf_core_cand_list *cands)
+void bpf_core_free_cands(struct bpf_core_cand_list *cands)
 {
+	if (!cands)
+		return;
+
 	free(cands->cands);
 	free(cands);
 }
 
-static int bpf_core_add_cands(struct bpf_core_cand *local_cand,
-			      size_t local_essent_len,
-			      const struct btf *targ_btf,
-			      const char *targ_btf_name,
-			      int targ_start_id,
-			      struct bpf_core_cand_list *cands)
+int bpf_core_add_cands(struct bpf_core_cand *local_cand,
+		       size_t local_essent_len,
+		       const struct btf *targ_btf,
+		       const char *targ_btf_name,
+		       int targ_start_id,
+		       struct bpf_core_cand_list *cands)
 {
 	struct bpf_core_cand *new_cands, *cand;
 	const struct btf_type *t, *local_t;

tools/lib/bpf/libbpf_internal.h

@@ -529,4 +529,13 @@ static inline int ensure_good_fd(int fd)
 	return fd;
 }
 
+/* The following two functions are exposed to bpftool */
+int bpf_core_add_cands(struct bpf_core_cand *local_cand,
+		       size_t local_essent_len,
+		       const struct btf *targ_btf,
+		       const char *targ_btf_name,
+		       int targ_start_id,
+		       struct bpf_core_cand_list *cands);
+void bpf_core_free_cands(struct bpf_core_cand_list *cands);
+
 #endif /* __LIBBPF_LIBBPF_INTERNAL_H */