tools: bpftool: provide JSON output for all possible commands

As all commands can now return JSON output (possibly just a "null"
value), output of `bpftool --json batch file FILE` should also be fully
JSON compliant.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 1 deletions

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 41bd5390b4fc..e07f35ff80d1 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -602,11 +602,21 @@ err_free:
 
 static int do_pin(int argc, char **argv)
 {
-        return do_pin_any(argc, argv, bpf_prog_get_fd_by_id);
+        int err;
+
+        err = do_pin_any(argc, argv, bpf_prog_get_fd_by_id);
+        if (!err && json_output)
+                jsonw_null(json_wtr);
+        return err;
 }
 
 static int do_help(int argc, char **argv)
 {
+        if (json_output) {
+                jsonw_null(json_wtr);
+                return 0;
+        }
+
         fprintf(stderr,
                 "Usage: %s %s show [PROG]\n"
                 "       %s %s dump xlated PROG [{ file FILE | opcodes }]\n"