[PATCH bpf-next v2] bpftool: add current libbpf_strict mode to version output

[Stanislav Fomichev <sdf@xxxxxxxxxx>]

+ bpftool --legacy --version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool --version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --legacy --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --json --legacy version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":false,"skeletons":true}}
+ bpftool --json version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":true,"skeletons":true}}

v2:
- fixes for -h and -V (Quentin Monnet)

Suggested-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
 tools/bpf/bpftool/main.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 473791e87f7d..601d0ee5e6d3 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -93,6 +93,7 @@ static int do_version(int argc, char **argv)
 		jsonw_name(json_wtr, "features");
 		jsonw_start_object(json_wtr);	/* features */
 		jsonw_bool_field(json_wtr, "libbfd", has_libbfd);
+		jsonw_bool_field(json_wtr, "libbpf_strict", !legacy_libbpf);
 		jsonw_bool_field(json_wtr, "skeletons", has_skeletons);
 		jsonw_end_object(json_wtr);	/* features */
 
@@ -106,6 +107,10 @@ static int do_version(int argc, char **argv)
 			printf(" libbfd");
 			nb_features++;
 		}
+		if (!legacy_libbpf) {
+			printf("%s libbpf_strict", nb_features++ ? "," : "");
+			nb_features++;
+		}
 		if (has_skeletons)
 			printf("%s skeletons", nb_features++ ? "," : "");
 		printf("\n");
@@ -414,9 +419,11 @@ int main(int argc, char **argv)
 				  options, NULL)) >= 0) {
 		switch (opt) {
 		case 'V':
-			return do_version(argc, argv);
+			last_do_help = do_version;
+			break;
 		case 'h':
-			return do_help(argc, argv);
+			last_do_help = do_help;
+			break;
 		case 'p':
 			pretty_output = true;
 			/* fall through */
@@ -476,7 +483,7 @@ int main(int argc, char **argv)
 
 	argc -= optind;
 	argv += optind;
-	if (argc < 0)
+	if (argc < 1)
 		usage();
 
 	ret = cmd_select(cmds, argc, argv, do_help);
-- 
2.34.0.rc1.387.gb447b232ab-goog