tools/bpf/bpftool/json_writer.h

   1 /* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
   2 /*
   3  * Simple streaming JSON writer
   4  *
   5  * This takes care of the annoying bits of JSON syntax like the commas
   6  * after elements
   7  *
   8  * Authors:     Stephen Hemminger <stephen@networkplumber.org>
   9  */
  10
  11 #ifndef _JSON_WRITER_H_
  12 #define _JSON_WRITER_H_
  13
  14 #include <stdbool.h>
  15 #include <stdint.h>
  16 #include <stdarg.h>
  17 #include <stdio.h>
  18 #include <linux/compiler.h>
  19
  20 /* Opaque class structure */
  21 typedef struct json_writer json_writer_t;
  22
  23 /* Create a new JSON stream */
  24 json_writer_t *jsonw_new(FILE *f);
  25 /* End output to JSON stream */
  26 void jsonw_destroy(json_writer_t **self_p);
  27
  28 /* Cause output to have pretty whitespace */
  29 void jsonw_pretty(json_writer_t *self, bool on);
  30
  31 /* Reset separator to create new JSON */
  32 void jsonw_reset(json_writer_t *self);
  33
  34 /* Add property name */
  35 void jsonw_name(json_writer_t *self, const char *name);
  36
  37 /* Add value  */
  38 void __printf(2, 0) jsonw_vprintf_enquote(json_writer_t *self, const char *fmt,
  39                                           va_list ap);
  40 void __printf(2, 3) jsonw_printf(json_writer_t *self, const char *fmt, ...);
  41 void jsonw_string(json_writer_t *self, const char *value);
  42 void jsonw_bool(json_writer_t *self, bool value);
  43 void jsonw_float(json_writer_t *self, double number);
  44 void jsonw_float_fmt(json_writer_t *self, const char *fmt, double num);
  45 void jsonw_uint(json_writer_t *self, uint64_t number);
  46 void jsonw_hu(json_writer_t *self, unsigned short number);
  47 void jsonw_int(json_writer_t *self, int64_t number);
  48 void jsonw_null(json_writer_t *self);
  49 void jsonw_lluint(json_writer_t *self, unsigned long long int num);
  50
  51 /* Useful Combinations of name and value */
  52 void jsonw_string_field(json_writer_t *self, const char *prop, const char *val);
  53 void jsonw_bool_field(json_writer_t *self, const char *prop, bool value);
  54 void jsonw_float_field(json_writer_t *self, const char *prop, double num);
  55 void jsonw_uint_field(json_writer_t *self, const char *prop, uint64_t num);
  56 void jsonw_hu_field(json_writer_t *self, const char *prop, unsigned short num);
  57 void jsonw_int_field(json_writer_t *self, const char *prop, int64_t num);
  58 void jsonw_null_field(json_writer_t *self, const char *prop);
  59 void jsonw_lluint_field(json_writer_t *self, const char *prop,
  60                         unsigned long long int num);
  61 void jsonw_float_field_fmt(json_writer_t *self, const char *prop,
  62                            const char *fmt, double val);
  63
  64 /* Collections */
  65 void jsonw_start_object(json_writer_t *self);
  66 void jsonw_end_object(json_writer_t *self);
  67
  68 void jsonw_start_array(json_writer_t *self);
  69 void jsonw_end_array(json_writer_t *self);
  70
  71 /* Override default exception handling */
  72 typedef void (jsonw_err_handler_fn)(const char *);
  73
  74 #endif /* _JSON_WRITER_H_ */