lib/json.h

   1 /* json-c wrapper
   2  * Copyright (C) 2015 Cumulus Networks, Inc.
   3  *
   4  * This file is part of GNU Zebra.
   5  *
   6  * GNU Zebra is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * GNU Zebra is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef _QUAGGA_JSON_H
  22 #define _QUAGGA_JSON_H
  23
  24 #ifdef __cplusplus
  25 extern "C" {
  26 #endif
  27
  28 #include "command.h"
  29 #include "printfrr.h"
  30 #include <json-c/json.h>
  31
  32 /*
  33  * FRR style JSON iteration.
  34  * Usage: JSON_FOREACH(...) { ... }
  35  */
  36 #define JSON_FOREACH(jo, joi, join)                                            \
  37         /* struct json_object *jo; */                                          \
  38         /* struct json_object_iterator joi; */                                 \
  39         /* struct json_object_iterator join; */                                \
  40         for ((joi) = json_object_iter_begin((jo)),                             \
  41             (join) = json_object_iter_end((jo));                               \
  42              json_object_iter_equal(&(joi), &(join)) == 0;                     \
  43              json_object_iter_next(&(joi)))
  44
  45 #define JSON_OBJECT_NEW_ARRAY(json_func, fields, n)                            \
  46         ({                                                                     \
  47                 struct json_object *_json_array = json_object_new_array();     \
  48                 for (int _i = 0; _i < (n); _i++)                               \
  49                         json_object_array_add(_json_array,                     \
  50                                               (json_func)((fields)[_i]));      \
  51                 (_json_array);                                                 \
  52         })
  53
  54 extern bool use_json(const int argc, struct cmd_token *argv[]);
  55 extern void json_object_string_add(struct json_object *obj, const char *key,
  56                                    const char *s);
  57 extern void json_object_int_add(struct json_object *obj, const char *key,
  58                                 int64_t i);
  59 void json_object_boolean_add(struct json_object *obj, const char *key,
  60                              bool val);
  61
  62 extern void json_object_double_add(struct json_object *obj, const char *key,
  63                                    double i);
  64 extern void json_object_boolean_false_add(struct json_object *obj,
  65                                           const char *key);
  66 extern void json_object_boolean_true_add(struct json_object *obj,
  67                                          const char *key);
  68 extern struct json_object *json_object_lock(struct json_object *obj);
  69 extern void json_object_free(struct json_object *obj);
  70 extern void json_array_string_add(json_object *json, const char *str);
  71
  72 /* printfrr => json helpers */
  73
  74 PRINTFRR(3, 0)
  75 extern void json_object_string_addv(struct json_object *obj, const char *key,
  76                                     const char *fmt, va_list args);
  77 PRINTFRR(3, 4)
  78 static inline void json_object_string_addf(struct json_object *obj,
  79                                            const char *key, const char *fmt,
  80                                            ...)
  81 {
  82         va_list args;
  83
  84         va_start(args, fmt);
  85         json_object_string_addv(obj, key, fmt, args);
  86         va_end(args);
  87 }
  88
  89 PRINTFRR(2, 0)
  90 extern void json_array_string_addv(json_object *json, const char *fmt,
  91                                    va_list args);
  92 PRINTFRR(2, 3)
  93 static inline void json_array_string_addf(struct json_object *obj,
  94                                           const char *fmt, ...)
  95 {
  96         va_list args;
  97
  98         va_start(args, fmt);
  99         json_array_string_addv(obj, fmt, args);
 100         va_end(args);
 101 }
 102
 103 PRINTFRR(1, 0)
 104 extern struct json_object *json_object_new_stringv(const char *fmt,
 105                                                    va_list args);
 106 PRINTFRR(1, 2)
 107 static inline struct json_object *json_object_new_stringf(const char *fmt, ...)
 108 {
 109         struct json_object *ret;
 110         va_list args;
 111
 112         va_start(args, fmt);
 113         ret = json_object_new_stringv(fmt, args);
 114         va_end(args);
 115
 116         return ret;
 117 }
 118
 119 /* NOTE: argument order differs! (due to varargs)
 120  *   json_object_object_add(parent, key, child)
 121  *   json_object_object_addv(parent, child, key, va)
 122  *   json_object_object_addf(parent, child, key, ...)
 123  * (would be weird to have the child inbetween the format string and args)
 124  */
 125 PRINTFRR(3, 0)
 126 extern void json_object_object_addv(struct json_object *parent,
 127                                     struct json_object *child,
 128                                     const char *keyfmt, va_list args);
 129 PRINTFRR(3, 4)
 130 static inline void json_object_object_addf(struct json_object *parent,
 131                                            struct json_object *child,
 132                                            const char *keyfmt, ...)
 133 {
 134         va_list args;
 135
 136         va_start(args, keyfmt);
 137         json_object_object_addv(parent, child, keyfmt, args);
 138         va_end(args);
 139 }
 140
 141 #define JSON_STR "JavaScript Object Notation\n"
 142
 143 /* NOTE: json-c lib has following commit 316da85 which
 144  * handles escape of forward slash.
 145  * This allows prefix  "20.0.14.0\/24":{
 146  * to  "20.0.14.0/24":{ some platforms do not have
 147  * latest copy of json-c where defining below macro.
 148  */
 149
 150 #ifndef JSON_C_TO_STRING_NOSLASHESCAPE
 151
 152 /**
 153   * Don't escape forward slashes.
 154   */
 155 #define JSON_C_TO_STRING_NOSLASHESCAPE (1<<4)
 156 #endif
 157
 158 #ifdef __cplusplus
 159 }
 160 #endif
 161
 162 #endif /* _QUAGGA_JSON_H */