libbpf: Fix single-line struct definition output in btf_dump

[ Upstream commit 872aec4b5f635d94111d48ec3c57fbe078d64e7d ]

btf_dump APIs emit unnecessary tabs when emitting struct/union
definition that fits on the single line. Before this patch we'd get:

struct blah {<tab>};

This patch fixes this and makes sure that we get more natural:

struct blah {};

Fixes: 44a726c3f23c ("bpftool: Print newline before '}' for struct with padding only fields")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221212211505.558851-2-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index 80a15a6802094d6f8cbee7d7db461de82c98bd8e..4cd1d49c94d6dd5b3fde762b088d9150c50fd123 100644 (file)
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -1015,9 +1015,12 @@ static void btf_dump_emit_struct_def(struct btf_dump *d,
         * Keep `struct empty {}` on a single line,
         * only print newline when there are regular or padding fields.
         */
-       if (vlen || t->size)
+       if (vlen || t->size) {
                btf_dump_printf(d, "\n");
-       btf_dump_printf(d, "%s}", pfx(lvl));
+               btf_dump_printf(d, "%s}", pfx(lvl));
+       } else {
+               btf_dump_printf(d, "}");
+       }
        if (packed)
                btf_dump_printf(d, " __attribute__((packed))");
 }