linux_dsm_epyc7002/tools/bpf/bpftool/main.c
Quentin Monnet 146882a37d tools: bpftool: make error message from getopt_long() JSON-friendly
If `getopt_long()` meets an unknown option, it prints its own error
message to standard error output. While this does not strictly break
JSON output, it is the only case bpftool prints something to standard
error output if JSON output is required. All other errors are printed on
standard output as JSON objects, so that an external program does not
have to parse stderr.

This is changed by setting the global variable `opterr` to 0.
Furthermore, p_err() is used to reproduce the error message in a more
JSON-friendly way, so that users still get to know what the erroneous
option is.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-30 02:09:29 +01:00

344 lines
7.1 KiB
C

/*
* Copyright (C) 2017 Netronome Systems, Inc.
*
* This software is dual licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree or the BSD 2-Clause License provided below. You have the
* option to license this software under the complete terms of either license.
*
* The BSD 2-Clause License:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/* Author: Jakub Kicinski <kubakici@wp.pl> */
#include <bfd.h>
#include <ctype.h>
#include <errno.h>
#include <getopt.h>
#include <linux/bpf.h>
#include <linux/version.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <bpf.h>
#include "main.h"
const char *bin_name;
static int last_argc;
static char **last_argv;
static int (*last_do_help)(int argc, char **argv);
json_writer_t *json_wtr;
bool pretty_output;
bool json_output;
bool show_pinned;
struct pinned_obj_table prog_table;
struct pinned_obj_table map_table;
static void __noreturn clean_and_exit(int i)
{
if (json_output)
jsonw_destroy(&json_wtr);
exit(i);
}
void usage(void)
{
last_do_help(last_argc - 1, last_argv + 1);
clean_and_exit(-1);
}
static int do_help(int argc, char **argv)
{
if (json_output) {
jsonw_null(json_wtr);
return 0;
}
fprintf(stderr,
"Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
" %s batch file FILE\n"
" %s version\n"
"\n"
" OBJECT := { prog | map }\n"
" " HELP_SPEC_OPTIONS "\n"
"",
bin_name, bin_name, bin_name);
return 0;
}
static int do_version(int argc, char **argv)
{
unsigned int version[3];
version[0] = LINUX_VERSION_CODE >> 16;
version[1] = LINUX_VERSION_CODE >> 8 & 0xf;
version[2] = LINUX_VERSION_CODE & 0xf;
if (json_output) {
jsonw_start_object(json_wtr);
jsonw_name(json_wtr, "version");
jsonw_printf(json_wtr, "\"%u.%u.%u\"",
version[0], version[1], version[2]);
jsonw_end_object(json_wtr);
} else {
printf("%s v%u.%u.%u\n", bin_name,
version[0], version[1], version[2]);
}
return 0;
}
int cmd_select(const struct cmd *cmds, int argc, char **argv,
int (*help)(int argc, char **argv))
{
unsigned int i;
last_argc = argc;
last_argv = argv;
last_do_help = help;
if (argc < 1 && cmds[0].func)
return cmds[0].func(argc, argv);
for (i = 0; cmds[i].func; i++)
if (is_prefix(*argv, cmds[i].cmd))
return cmds[i].func(argc - 1, argv + 1);
help(argc - 1, argv + 1);
return -1;
}
bool is_prefix(const char *pfx, const char *str)
{
if (!pfx)
return false;
if (strlen(str) < strlen(pfx))
return false;
return !memcmp(str, pfx, strlen(pfx));
}
void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
{
unsigned char *data = arg;
unsigned int i;
for (i = 0; i < n; i++) {
const char *pfx = "";
if (!i)
/* nothing */;
else if (!(i % 16))
fprintf(f, "\n");
else if (!(i % 8))
fprintf(f, " ");
else
pfx = sep;
fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
}
}
static int do_batch(int argc, char **argv);
static const struct cmd cmds[] = {
{ "help", do_help },
{ "batch", do_batch },
{ "prog", do_prog },
{ "map", do_map },
{ "version", do_version },
{ 0 }
};
static int do_batch(int argc, char **argv)
{
unsigned int lines = 0;
char *n_argv[4096];
char buf[65536];
int n_argc;
FILE *fp;
int err;
int i;
if (argc < 2) {
p_err("too few parameters for batch");
return -1;
} else if (!is_prefix(*argv, "file")) {
p_err("expected 'file', got: %s", *argv);
return -1;
} else if (argc > 2) {
p_err("too many parameters for batch");
return -1;
}
NEXT_ARG();
fp = fopen(*argv, "r");
if (!fp) {
p_err("Can't open file (%s): %s", *argv, strerror(errno));
return -1;
}
if (json_output)
jsonw_start_array(json_wtr);
while (fgets(buf, sizeof(buf), fp)) {
if (strlen(buf) == sizeof(buf) - 1) {
errno = E2BIG;
break;
}
n_argc = 0;
n_argv[n_argc] = strtok(buf, " \t\n");
while (n_argv[n_argc]) {
n_argc++;
if (n_argc == ARRAY_SIZE(n_argv)) {
p_err("line %d has too many arguments, skip",
lines);
n_argc = 0;
break;
}
n_argv[n_argc] = strtok(NULL, " \t\n");
}
if (!n_argc)
continue;
if (json_output) {
jsonw_start_object(json_wtr);
jsonw_name(json_wtr, "command");
jsonw_start_array(json_wtr);
for (i = 0; i < n_argc; i++)
jsonw_string(json_wtr, n_argv[i]);
jsonw_end_array(json_wtr);
jsonw_name(json_wtr, "output");
}
err = cmd_select(cmds, n_argc, n_argv, do_help);
if (json_output)
jsonw_end_object(json_wtr);
if (err)
goto err_close;
lines++;
}
if (errno && errno != ENOENT) {
perror("reading batch file failed");
err = -1;
} else {
p_info("processed %d lines", lines);
err = 0;
}
err_close:
fclose(fp);
if (json_output)
jsonw_end_array(json_wtr);
return err;
}
int main(int argc, char **argv)
{
static const struct option options[] = {
{ "json", no_argument, NULL, 'j' },
{ "help", no_argument, NULL, 'h' },
{ "pretty", no_argument, NULL, 'p' },
{ "version", no_argument, NULL, 'V' },
{ "bpffs", no_argument, NULL, 'f' },
{ 0 }
};
int opt, ret;
last_do_help = do_help;
pretty_output = false;
json_output = false;
show_pinned = false;
bin_name = argv[0];
hash_init(prog_table.table);
hash_init(map_table.table);
opterr = 0;
while ((opt = getopt_long(argc, argv, "Vhpjf",
options, NULL)) >= 0) {
switch (opt) {
case 'V':
return do_version(argc, argv);
case 'h':
return do_help(argc, argv);
case 'p':
pretty_output = true;
/* fall through */
case 'j':
if (!json_output) {
json_wtr = jsonw_new(stdout);
if (!json_wtr) {
p_err("failed to create JSON writer");
return -1;
}
json_output = true;
}
jsonw_pretty(json_wtr, pretty_output);
break;
case 'f':
show_pinned = true;
break;
default:
p_err("unrecognized option '%s'", argv[optind - 1]);
if (json_output)
clean_and_exit(-1);
else
usage();
}
}
argc -= optind;
argv += optind;
if (argc < 0)
usage();
bfd_init();
ret = cmd_select(cmds, argc, argv, do_help);
if (json_output)
jsonw_destroy(&json_wtr);
if (show_pinned) {
delete_pinned_obj_table(&prog_table);
delete_pinned_obj_table(&map_table);
}
return ret;
}