bpftool: clean-up usage of libbpf_get_error()

bpftool is now totally compliant with libbpf 1.0 mode and is not
expected to be compiled with pre-1.0, let's clean-up the usage of
libbpf_get_error().

The changes stay aligned with returned errors always negative.

- In tools/bpf/bpftool/btf.c This fixes an uninitialized local
variable `err` in function do_dump() because it may now be returned
without having been set.
- This also removes the checks on NULL pointers before calling
btf__free() because that function already does the check.

Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@industrialdiscipline.com>
Link: https://lore.kernel.org/r/20221120112515.38165-5-sahid.ferdjaoui@industrialdiscipline.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index c53c553adcac..08d0ac543c67 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -510,10 +510,9 @@ int main(int argc, char **argv)
 			break;
 		case 'B':
 			base_btf = btf__parse(optarg, NULL);
-			if (libbpf_get_error(base_btf)) {
-				p_err("failed to parse base BTF at '%s': %ld\n",
-				      optarg, libbpf_get_error(base_btf));
-				base_btf = NULL;
+			if (!base_btf) {
+				p_err("failed to parse base BTF at '%s': %d\n",
+				      optarg, -errno);
 				return -1;
 			}
 			break;