mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 00:17:44 +00:00
aff52e685e
Dump metadata in the 'bpftool prog' list if it's present.
For some formatting some BTF code is put directly in the
metadata dumping. Sanity checks on the map and the kind of the btf_type
to make sure we are actually dumping what we are expecting.
A helper jsonw_reset is added to json writer so we can reuse the same
json writer without having extraneous commas.
Sample output:
$ bpftool prog
6: cgroup_skb name prog tag bcf7977d3b93787c gpl
[...]
btf_id 4
metadata:
a = "foo"
b = 1
$ bpftool prog --json --pretty
[{
"id": 6,
[...]
"btf_id": 4,
"metadata": {
"a": "foo",
"b": 1
}
}
]
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: YiFei Zhu <zhuyifei1999@gmail.com>
Link: https://lore.kernel.org/bpf/20200915234543.3220146-5-sdf@google.com
358 lines
6.7 KiB
C
358 lines
6.7 KiB
C
// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
|
|
/*
|
|
* Simple streaming JSON writer
|
|
*
|
|
* This takes care of the annoying bits of JSON syntax like the commas
|
|
* after elements
|
|
*
|
|
* Authors: Stephen Hemminger <stephen@networkplumber.org>
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdbool.h>
|
|
#include <stdarg.h>
|
|
#include <assert.h>
|
|
#include <malloc.h>
|
|
#include <inttypes.h>
|
|
#include <stdint.h>
|
|
|
|
#include "json_writer.h"
|
|
|
|
struct json_writer {
|
|
FILE *out; /* output file */
|
|
unsigned depth; /* nesting */
|
|
bool pretty; /* optional whitepace */
|
|
char sep; /* either nul or comma */
|
|
};
|
|
|
|
/* indentation for pretty print */
|
|
static void jsonw_indent(json_writer_t *self)
|
|
{
|
|
unsigned i;
|
|
for (i = 0; i < self->depth; ++i)
|
|
fputs(" ", self->out);
|
|
}
|
|
|
|
/* end current line and indent if pretty printing */
|
|
static void jsonw_eol(json_writer_t *self)
|
|
{
|
|
if (!self->pretty)
|
|
return;
|
|
|
|
putc('\n', self->out);
|
|
jsonw_indent(self);
|
|
}
|
|
|
|
/* If current object is not empty print a comma */
|
|
static void jsonw_eor(json_writer_t *self)
|
|
{
|
|
if (self->sep != '\0')
|
|
putc(self->sep, self->out);
|
|
self->sep = ',';
|
|
}
|
|
|
|
|
|
/* Output JSON encoded string */
|
|
/* Handles C escapes, does not do Unicode */
|
|
static void jsonw_puts(json_writer_t *self, const char *str)
|
|
{
|
|
putc('"', self->out);
|
|
for (; *str; ++str)
|
|
switch (*str) {
|
|
case '\t':
|
|
fputs("\\t", self->out);
|
|
break;
|
|
case '\n':
|
|
fputs("\\n", self->out);
|
|
break;
|
|
case '\r':
|
|
fputs("\\r", self->out);
|
|
break;
|
|
case '\f':
|
|
fputs("\\f", self->out);
|
|
break;
|
|
case '\b':
|
|
fputs("\\b", self->out);
|
|
break;
|
|
case '\\':
|
|
fputs("\\n", self->out);
|
|
break;
|
|
case '"':
|
|
fputs("\\\"", self->out);
|
|
break;
|
|
case '\'':
|
|
fputs("\\\'", self->out);
|
|
break;
|
|
default:
|
|
putc(*str, self->out);
|
|
}
|
|
putc('"', self->out);
|
|
}
|
|
|
|
/* Create a new JSON stream */
|
|
json_writer_t *jsonw_new(FILE *f)
|
|
{
|
|
json_writer_t *self = malloc(sizeof(*self));
|
|
if (self) {
|
|
self->out = f;
|
|
self->depth = 0;
|
|
self->pretty = false;
|
|
self->sep = '\0';
|
|
}
|
|
return self;
|
|
}
|
|
|
|
/* End output to JSON stream */
|
|
void jsonw_destroy(json_writer_t **self_p)
|
|
{
|
|
json_writer_t *self = *self_p;
|
|
|
|
assert(self->depth == 0);
|
|
fputs("\n", self->out);
|
|
fflush(self->out);
|
|
free(self);
|
|
*self_p = NULL;
|
|
}
|
|
|
|
void jsonw_pretty(json_writer_t *self, bool on)
|
|
{
|
|
self->pretty = on;
|
|
}
|
|
|
|
void jsonw_reset(json_writer_t *self)
|
|
{
|
|
assert(self->depth == 0);
|
|
self->sep = '\0';
|
|
}
|
|
|
|
/* Basic blocks */
|
|
static void jsonw_begin(json_writer_t *self, int c)
|
|
{
|
|
jsonw_eor(self);
|
|
putc(c, self->out);
|
|
++self->depth;
|
|
self->sep = '\0';
|
|
}
|
|
|
|
static void jsonw_end(json_writer_t *self, int c)
|
|
{
|
|
assert(self->depth > 0);
|
|
|
|
--self->depth;
|
|
if (self->sep != '\0')
|
|
jsonw_eol(self);
|
|
putc(c, self->out);
|
|
self->sep = ',';
|
|
}
|
|
|
|
|
|
/* Add a JSON property name */
|
|
void jsonw_name(json_writer_t *self, const char *name)
|
|
{
|
|
jsonw_eor(self);
|
|
jsonw_eol(self);
|
|
self->sep = '\0';
|
|
jsonw_puts(self, name);
|
|
putc(':', self->out);
|
|
if (self->pretty)
|
|
putc(' ', self->out);
|
|
}
|
|
|
|
void jsonw_vprintf_enquote(json_writer_t *self, const char *fmt, va_list ap)
|
|
{
|
|
jsonw_eor(self);
|
|
putc('"', self->out);
|
|
vfprintf(self->out, fmt, ap);
|
|
putc('"', self->out);
|
|
}
|
|
|
|
void jsonw_printf(json_writer_t *self, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
|
|
va_start(ap, fmt);
|
|
jsonw_eor(self);
|
|
vfprintf(self->out, fmt, ap);
|
|
va_end(ap);
|
|
}
|
|
|
|
/* Collections */
|
|
void jsonw_start_object(json_writer_t *self)
|
|
{
|
|
jsonw_begin(self, '{');
|
|
}
|
|
|
|
void jsonw_end_object(json_writer_t *self)
|
|
{
|
|
jsonw_end(self, '}');
|
|
}
|
|
|
|
void jsonw_start_array(json_writer_t *self)
|
|
{
|
|
jsonw_begin(self, '[');
|
|
}
|
|
|
|
void jsonw_end_array(json_writer_t *self)
|
|
{
|
|
jsonw_end(self, ']');
|
|
}
|
|
|
|
/* JSON value types */
|
|
void jsonw_string(json_writer_t *self, const char *value)
|
|
{
|
|
jsonw_eor(self);
|
|
jsonw_puts(self, value);
|
|
}
|
|
|
|
void jsonw_bool(json_writer_t *self, bool val)
|
|
{
|
|
jsonw_printf(self, "%s", val ? "true" : "false");
|
|
}
|
|
|
|
void jsonw_null(json_writer_t *self)
|
|
{
|
|
jsonw_printf(self, "null");
|
|
}
|
|
|
|
void jsonw_float_fmt(json_writer_t *self, const char *fmt, double num)
|
|
{
|
|
jsonw_printf(self, fmt, num);
|
|
}
|
|
|
|
#ifdef notused
|
|
void jsonw_float(json_writer_t *self, double num)
|
|
{
|
|
jsonw_printf(self, "%g", num);
|
|
}
|
|
#endif
|
|
|
|
void jsonw_hu(json_writer_t *self, unsigned short num)
|
|
{
|
|
jsonw_printf(self, "%hu", num);
|
|
}
|
|
|
|
void jsonw_uint(json_writer_t *self, uint64_t num)
|
|
{
|
|
jsonw_printf(self, "%"PRIu64, num);
|
|
}
|
|
|
|
void jsonw_lluint(json_writer_t *self, unsigned long long int num)
|
|
{
|
|
jsonw_printf(self, "%llu", num);
|
|
}
|
|
|
|
void jsonw_int(json_writer_t *self, int64_t num)
|
|
{
|
|
jsonw_printf(self, "%"PRId64, num);
|
|
}
|
|
|
|
/* Basic name/value objects */
|
|
void jsonw_string_field(json_writer_t *self, const char *prop, const char *val)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_string(self, val);
|
|
}
|
|
|
|
void jsonw_bool_field(json_writer_t *self, const char *prop, bool val)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_bool(self, val);
|
|
}
|
|
|
|
#ifdef notused
|
|
void jsonw_float_field(json_writer_t *self, const char *prop, double val)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_float(self, val);
|
|
}
|
|
#endif
|
|
|
|
void jsonw_float_field_fmt(json_writer_t *self,
|
|
const char *prop,
|
|
const char *fmt,
|
|
double val)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_float_fmt(self, fmt, val);
|
|
}
|
|
|
|
void jsonw_uint_field(json_writer_t *self, const char *prop, uint64_t num)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_uint(self, num);
|
|
}
|
|
|
|
void jsonw_hu_field(json_writer_t *self, const char *prop, unsigned short num)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_hu(self, num);
|
|
}
|
|
|
|
void jsonw_lluint_field(json_writer_t *self,
|
|
const char *prop,
|
|
unsigned long long int num)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_lluint(self, num);
|
|
}
|
|
|
|
void jsonw_int_field(json_writer_t *self, const char *prop, int64_t num)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_int(self, num);
|
|
}
|
|
|
|
void jsonw_null_field(json_writer_t *self, const char *prop)
|
|
{
|
|
jsonw_name(self, prop);
|
|
jsonw_null(self);
|
|
}
|
|
|
|
#ifdef TEST
|
|
int main(int argc, char **argv)
|
|
{
|
|
json_writer_t *wr = jsonw_new(stdout);
|
|
|
|
jsonw_start_object(wr);
|
|
jsonw_pretty(wr, true);
|
|
jsonw_name(wr, "Vyatta");
|
|
jsonw_start_object(wr);
|
|
jsonw_string_field(wr, "url", "http://vyatta.com");
|
|
jsonw_uint_field(wr, "downloads", 2000000ul);
|
|
jsonw_float_field(wr, "stock", 8.16);
|
|
|
|
jsonw_name(wr, "ARGV");
|
|
jsonw_start_array(wr);
|
|
while (--argc)
|
|
jsonw_string(wr, *++argv);
|
|
jsonw_end_array(wr);
|
|
|
|
jsonw_name(wr, "empty");
|
|
jsonw_start_array(wr);
|
|
jsonw_end_array(wr);
|
|
|
|
jsonw_name(wr, "NIL");
|
|
jsonw_start_object(wr);
|
|
jsonw_end_object(wr);
|
|
|
|
jsonw_null_field(wr, "my_null");
|
|
|
|
jsonw_name(wr, "special chars");
|
|
jsonw_start_array(wr);
|
|
jsonw_string_field(wr, "slash", "/");
|
|
jsonw_string_field(wr, "newline", "\n");
|
|
jsonw_string_field(wr, "tab", "\t");
|
|
jsonw_string_field(wr, "ff", "\f");
|
|
jsonw_string_field(wr, "quote", "\"");
|
|
jsonw_string_field(wr, "tick", "\'");
|
|
jsonw_string_field(wr, "backslash", "\\");
|
|
jsonw_end_array(wr);
|
|
|
|
jsonw_end_object(wr);
|
|
|
|
jsonw_end_object(wr);
|
|
jsonw_destroy(&wr);
|
|
return 0;
|
|
}
|
|
|
|
#endif
|