Merge branch 'bpf-bpftool-json-fixes'

Quentin Monnet says:

====================
These are two minor fixes to avoid breaking JSON output in batch mode. The
first one makes bpftool output a "null" JSON object, as expected in batch
mode if nothing else is to be printed, when dumping program instructions
into an output file. The second one replaces a call to "perror()" with
something that does not break JSON when parsing input file for batch mode.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

2 files changed, 4 insertions, 1 deletions

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 3a0396d87c42..185acfa229b5 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -244,7 +244,7 @@ static int do_batch(int argc, char **argv)
         }
 
         if (errno && errno != ENOENT) {
-                perror("reading batch file failed");
+                p_err("reading batch file failed: %s", strerror(errno));
                 err = -1;
         } else {
                 p_info("processed %d lines", lines);
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index e8e2baaf93c2..e549e329be82 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -774,6 +774,9 @@ static int do_dump(int argc, char **argv)
                               n < 0 ? strerror(errno) : "short write");
                         goto err_free;
                 }
+
+                if (json_output)
+                        jsonw_null(json_wtr);
         } else {
                 if (member_len == &info.jited_prog_len) {
                         const char *name = NULL;