linux_dsm_epyc7002/tools/bpf/bpftool/json_writer.h
Quentin Monnet f05e2c32f7 tools: bpftool: add JSON output for bpftool prog dump xlated * command
Add a new printing function to dump translated eBPF instructions as
JSON. As for plain output, opcodes are printed only on request (when
`opcodes` is provided on the command line).

The disassembled output is generated by the same code that is used by
the kernel verifier.

Example output:

    $ bpftool --json --pretty prog dump xlated id 1
    [{
            "disasm": "(bf) r6 = r1"
        },{
            "disasm": "(61) r7 = *(u32 *)(r6 +16)"
        },{
            "disasm": "(95) exit"
        }
    ]

    $ bpftool --json --pretty prog dump xlated id 1 opcodes
    [{
            "disasm": "(bf) r6 = r1",
            "opcodes": {
                "code": "0xbf",
                "src_reg": "0x1",
                "dst_reg": "0x6",
                "off": ["0x00","0x00"
                ],
                "imm": ["0x00","0x00","0x00","0x00"
                ]
            }
        },{
            "disasm": "(61) r7 = *(u32 *)(r6 +16)",
            "opcodes": {
                "code": "0x61",
                "src_reg": "0x6",
                "dst_reg": "0x7",
                "off": ["0x10","0x00"
                ],
                "imm": ["0x00","0x00","0x00","0x00"
                ]
            }
        },{
            "disasm": "(95) exit",
            "opcodes": {
                "code": "0x95",
                "src_reg": "0x0",
                "dst_reg": "0x0",
                "off": ["0x00","0x00"
                ],
                "imm": ["0x00","0x00","0x00","0x00"
                ]
            }
        }
    ]

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>
2017-10-24 01:25:08 +01:00

73 lines
2.6 KiB
C

/*
* Simple streaming JSON writer
*
* This takes care of the annoying bits of JSON syntax like the commas
* after elements
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Stephen Hemminger <stephen@networkplumber.org>
*/
#ifndef _JSON_WRITER_H_
#define _JSON_WRITER_H_
#include <stdbool.h>
#include <stdint.h>
#include <stdarg.h>
/* Opaque class structure */
typedef struct json_writer json_writer_t;
/* Create a new JSON stream */
json_writer_t *jsonw_new(FILE *f);
/* End output to JSON stream */
void jsonw_destroy(json_writer_t **self_p);
/* Cause output to have pretty whitespace */
void jsonw_pretty(json_writer_t *self, bool on);
/* Add property name */
void jsonw_name(json_writer_t *self, const char *name);
/* Add value */
void jsonw_vprintf_enquote(json_writer_t *self, const char *fmt, va_list ap);
void jsonw_printf(json_writer_t *self, const char *fmt, ...);
void jsonw_string(json_writer_t *self, const char *value);
void jsonw_bool(json_writer_t *self, bool value);
void jsonw_float(json_writer_t *self, double number);
void jsonw_float_fmt(json_writer_t *self, const char *fmt, double num);
void jsonw_uint(json_writer_t *self, uint64_t number);
void jsonw_hu(json_writer_t *self, unsigned short number);
void jsonw_int(json_writer_t *self, int64_t number);
void jsonw_null(json_writer_t *self);
void jsonw_lluint(json_writer_t *self, unsigned long long int num);
/* Useful Combinations of name and value */
void jsonw_string_field(json_writer_t *self, const char *prop, const char *val);
void jsonw_bool_field(json_writer_t *self, const char *prop, bool value);
void jsonw_float_field(json_writer_t *self, const char *prop, double num);
void jsonw_uint_field(json_writer_t *self, const char *prop, uint64_t num);
void jsonw_hu_field(json_writer_t *self, const char *prop, unsigned short num);
void jsonw_int_field(json_writer_t *self, const char *prop, int64_t num);
void jsonw_null_field(json_writer_t *self, const char *prop);
void jsonw_lluint_field(json_writer_t *self, const char *prop,
unsigned long long int num);
void jsonw_float_field_fmt(json_writer_t *self, const char *prop,
const char *fmt, double val);
/* Collections */
void jsonw_start_object(json_writer_t *self);
void jsonw_end_object(json_writer_t *self);
void jsonw_start_array(json_writer_t *self);
void jsonw_end_array(json_writer_t *self);
/* Override default exception handling */
typedef void (jsonw_err_handler_fn)(const char *);
#endif /* _JSON_WRITER_H_ */