tools: bpftool: introduce --json and --pretty options

These two options can be used to ask for a JSON output (--j or -json),
and to make this JSON human-readable (-p or --pretty).

A json_writer object is created when JSON is required, and will be used
in follow-up commits to produce JSON output.

Note that --pretty implies --json.

Update for the manual pages and interactive help messages comes in a
later patch of the series.

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>
This commit is contained in:
Quentin Monnet 2017-10-23 09:24:07 -07:00 committed by David S. Miller
parent a2bc2e5c2c
commit d35efba99d
2 changed files with 35 additions and 3 deletions

View File

@ -51,6 +51,9 @@ const char *bin_name;
static int last_argc; static int last_argc;
static char **last_argv; static char **last_argv;
static int (*last_do_help)(int argc, char **argv); static int (*last_do_help)(int argc, char **argv);
json_writer_t *json_wtr;
bool pretty_output;
bool json_output;
void usage(void) void usage(void)
{ {
@ -217,22 +220,32 @@ err_close:
int main(int argc, char **argv) int main(int argc, char **argv)
{ {
static const struct option options[] = { static const struct option options[] = {
{ "json", no_argument, NULL, 'j' },
{ "help", no_argument, NULL, 'h' }, { "help", no_argument, NULL, 'h' },
{ "pretty", no_argument, NULL, 'p' },
{ "version", no_argument, NULL, 'V' }, { "version", no_argument, NULL, 'V' },
{ 0 } { 0 }
}; };
int opt; int opt, ret;
last_do_help = do_help; last_do_help = do_help;
pretty_output = false;
json_output = false;
bin_name = argv[0]; bin_name = argv[0];
while ((opt = getopt_long(argc, argv, "Vh", while ((opt = getopt_long(argc, argv, "Vhpj",
options, NULL)) >= 0) { options, NULL)) >= 0) {
switch (opt) { switch (opt) {
case 'V': case 'V':
return do_version(argc, argv); return do_version(argc, argv);
case 'h': case 'h':
return do_help(argc, argv); return do_help(argc, argv);
case 'p':
pretty_output = true;
/* fall through */
case 'j':
json_output = true;
break;
default: default:
usage(); usage();
} }
@ -243,7 +256,21 @@ int main(int argc, char **argv)
if (argc < 0) if (argc < 0)
usage(); usage();
if (json_output) {
json_wtr = jsonw_new(stdout);
if (!json_wtr) {
err("failed to create JSON writer\n");
return -1;
}
jsonw_pretty(json_wtr, pretty_output);
}
bfd_init(); bfd_init();
return cmd_select(cmds, argc, argv, do_help); ret = cmd_select(cmds, argc, argv, do_help);
if (json_output)
jsonw_destroy(&json_wtr);
return ret;
} }

View File

@ -43,6 +43,8 @@
#include <linux/bpf.h> #include <linux/bpf.h>
#include <linux/kernel.h> #include <linux/kernel.h>
#include "json_writer.h"
#define err(msg...) fprintf(stderr, "Error: " msg) #define err(msg...) fprintf(stderr, "Error: " msg)
#define warn(msg...) fprintf(stderr, "Warning: " msg) #define warn(msg...) fprintf(stderr, "Warning: " msg)
#define info(msg...) fprintf(stderr, msg) #define info(msg...) fprintf(stderr, msg)
@ -66,6 +68,9 @@ enum bpf_obj_type {
extern const char *bin_name; extern const char *bin_name;
extern json_writer_t *json_wtr;
extern bool json_output;
bool is_prefix(const char *pfx, const char *str); bool is_prefix(const char *pfx, const char *str);
void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep); void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep);
void usage(void) __attribute__((noreturn)); void usage(void) __attribute__((noreturn));