lib/json_print.c

   1 /*
   2  * json_print.c         "print regular or json output, based on json_writer".
   3  *
   4  *             This program is free software; you can redistribute it and/or
   5  *             modify it under the terms of the GNU General Public License
   6  *             as published by the Free Software Foundation; either version
   7  *             2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:    Julien Fortin, <julien@cumulusnetworks.com>
  10  */
  11
  12 #include <stdarg.h>
  13 #include <stdio.h>
  14
  15 #include "utils.h"
  16 #include "json_print.h"
  17
  18 static json_writer_t *_jw;
  19
  20 #define _IS_JSON_CONTEXT(type) ((type & PRINT_JSON || type & PRINT_ANY) && _jw)
  21 #define _IS_FP_CONTEXT(type) (!_jw && (type & PRINT_FP || type & PRINT_ANY))
  22
  23 static void __new_json_obj(int json, bool have_array)
  24 {
  25         if (json) {
  26                 _jw = jsonw_new(stdout);
  27                 if (!_jw) {
  28                         perror("json object");
  29                         exit(1);
  30                 }
  31                 if (pretty)
  32                         jsonw_pretty(_jw, true);
  33                 if (have_array)
  34                         jsonw_start_array(_jw);
  35         }
  36 }
  37
  38 static void __delete_json_obj(bool have_array)
  39 {
  40         if (_jw) {
  41                 if (have_array)
  42                         jsonw_end_array(_jw);
  43                 jsonw_destroy(&_jw);
  44         }
  45 }
  46
  47 void new_json_obj(int json)
  48 {
  49         __new_json_obj(json, true);
  50 }
  51
  52 void delete_json_obj(void)
  53 {
  54         __delete_json_obj(true);
  55 }
  56
  57 void new_json_obj_plain(int json)
  58 {
  59         __new_json_obj(json, false);
  60 }
  61
  62 void delete_json_obj_plain(void)
  63 {
  64         __delete_json_obj(false);
  65 }
  66
  67 bool is_json_context(void)
  68 {
  69         return _jw != NULL;
  70 }
  71
  72 json_writer_t *get_json_writer(void)
  73 {
  74         return _jw;
  75 }
  76
  77 void open_json_object(const char *str)
  78 {
  79         if (_IS_JSON_CONTEXT(PRINT_JSON)) {
  80                 if (str)
  81                         jsonw_name(_jw, str);
  82                 jsonw_start_object(_jw);
  83         }
  84 }
  85
  86 void close_json_object(void)
  87 {
  88         if (_IS_JSON_CONTEXT(PRINT_JSON))
  89                 jsonw_end_object(_jw);
  90 }
  91
  92 /*
  93  * Start json array or string array using
  94  * the provided string as json key (if not null)
  95  * or as array delimiter in non-json context.
  96  */
  97 void open_json_array(enum output_type type, const char *str)
  98 {
  99         if (_IS_JSON_CONTEXT(type)) {
 100                 if (str)
 101                         jsonw_name(_jw, str);
 102                 jsonw_start_array(_jw);
 103         } else if (_IS_FP_CONTEXT(type)) {
 104                 printf("%s", str);
 105         }
 106 }
 107
 108 /*
 109  * End json array or string array
 110  */
 111 void close_json_array(enum output_type type, const char *str)
 112 {
 113         if (_IS_JSON_CONTEXT(type)) {
 114                 jsonw_end_array(_jw);
 115         } else if (_IS_FP_CONTEXT(type)) {
 116                 printf("%s", str);
 117         }
 118 }
 119
 120 /*
 121  * pre-processor directive to generate similar
 122  * functions handling different types
 123  */
 124 #define _PRINT_FUNC(type_name, type)                                    \
 125         __attribute__((format(printf, 4, 0)))                           \
 126         int print_color_##type_name(enum output_type t,                 \
 127                                     enum color_attr color,              \
 128                                     const char *key,                    \
 129                                     const char *fmt,                    \
 130                                     type value)                         \
 131         {                                                               \
 132                 int ret = 0;                                            \
 133                 if (_IS_JSON_CONTEXT(t)) {                              \
 134                         if (!key)                                       \
 135                                 jsonw_##type_name(_jw, value);          \
 136                         else                                            \
 137                                 jsonw_##type_name##_field(_jw, key, value); \
 138                 } else if (_IS_FP_CONTEXT(t)) {                         \
 139                         ret = color_fprintf(stdout, color, fmt, value); \
 140                 }                                                       \
 141                 return ret;                                             \
 142         }
 143 _PRINT_FUNC(int, int);
 144 _PRINT_FUNC(s64, int64_t);
 145 _PRINT_FUNC(hhu, unsigned char);
 146 _PRINT_FUNC(hu, unsigned short);
 147 _PRINT_FUNC(uint, unsigned int);
 148 _PRINT_FUNC(u64, uint64_t);
 149 _PRINT_FUNC(luint, unsigned long);
 150 _PRINT_FUNC(lluint, unsigned long long);
 151 _PRINT_FUNC(float, double);
 152 #undef _PRINT_FUNC
 153
 154 #define _PRINT_NAME_VALUE_FUNC(type_name, type, format_char)             \
 155         void print_##type_name##_name_value(const char *name, type value)\
 156         {                                                                \
 157                 SPRINT_BUF(format);                                      \
 158                                                                          \
 159                 snprintf(format, SPRINT_BSIZE,                           \
 160                          "%s %%"#format_char, name);                     \
 161                 print_##type_name(PRINT_ANY, name, format, value);       \
 162         }
 163 _PRINT_NAME_VALUE_FUNC(uint, unsigned int, u);
 164 _PRINT_NAME_VALUE_FUNC(string, const char*, s);
 165 #undef _PRINT_NAME_VALUE_FUNC
 166
 167 int print_color_string(enum output_type type,
 168                        enum color_attr color,
 169                        const char *key,
 170                        const char *fmt,
 171                        const char *value)
 172 {
 173         int ret = 0;
 174
 175         if (_IS_JSON_CONTEXT(type)) {
 176                 if (key && !value)
 177                         jsonw_name(_jw, key);
 178                 else if (!key && value)
 179                         jsonw_string(_jw, value);
 180                 else
 181                         jsonw_string_field(_jw, key, value);
 182         } else if (_IS_FP_CONTEXT(type)) {
 183                 ret = color_fprintf(stdout, color, fmt, value);
 184         }
 185
 186         return ret;
 187 }
 188
 189 /*
 190  * value's type is bool. When using this function in FP context you can't pass
 191  * a value to it, you will need to use "is_json_context()" to have different
 192  * branch for json and regular output. grep -r "print_bool" for example
 193  */
 194 int print_color_bool(enum output_type type,
 195                      enum color_attr color,
 196                      const char *key,
 197                      const char *fmt,
 198                      bool value)
 199 {
 200         int ret = 0;
 201
 202         if (_IS_JSON_CONTEXT(type)) {
 203                 if (key)
 204                         jsonw_bool_field(_jw, key, value);
 205                 else
 206                         jsonw_bool(_jw, value);
 207         } else if (_IS_FP_CONTEXT(type)) {
 208                 ret = color_fprintf(stdout, color, fmt,
 209                                     value ? "true" : "false");
 210         }
 211
 212         return ret;
 213 }
 214
 215 /*
 216  * In JSON context uses hardcode %#x format: 42 -> 0x2a
 217  */
 218 int print_color_0xhex(enum output_type type,
 219                       enum color_attr color,
 220                       const char *key,
 221                       const char *fmt,
 222                       unsigned long long hex)
 223 {
 224         int ret = 0;
 225
 226         if (_IS_JSON_CONTEXT(type)) {
 227                 SPRINT_BUF(b1);
 228
 229                 snprintf(b1, sizeof(b1), "%#llx", hex);
 230                 print_string(PRINT_JSON, key, NULL, b1);
 231         } else if (_IS_FP_CONTEXT(type)) {
 232                 ret = color_fprintf(stdout, color, fmt, hex);
 233         }
 234
 235         return ret;
 236 }
 237
 238 int print_color_hex(enum output_type type,
 239                     enum color_attr color,
 240                     const char *key,
 241                     const char *fmt,
 242                     unsigned int hex)
 243 {
 244         int ret = 0;
 245
 246         if (_IS_JSON_CONTEXT(type)) {
 247                 SPRINT_BUF(b1);
 248
 249                 snprintf(b1, sizeof(b1), "%x", hex);
 250                 if (key)
 251                         jsonw_string_field(_jw, key, b1);
 252                 else
 253                         jsonw_string(_jw, b1);
 254         } else if (_IS_FP_CONTEXT(type)) {
 255                 ret = color_fprintf(stdout, color, fmt, hex);
 256         }
 257
 258         return ret;
 259 }
 260
 261 /*
 262  * In JSON context we don't use the argument "value" we simply call jsonw_null
 263  * whereas FP context can use "value" to output anything
 264  */
 265 int print_color_null(enum output_type type,
 266                      enum color_attr color,
 267                      const char *key,
 268                      const char *fmt,
 269                      const char *value)
 270 {
 271         int ret = 0;
 272
 273         if (_IS_JSON_CONTEXT(type)) {
 274                 if (key)
 275                         jsonw_null_field(_jw, key);
 276                 else
 277                         jsonw_null(_jw);
 278         } else if (_IS_FP_CONTEXT(type)) {
 279                 ret = color_fprintf(stdout, color, fmt, value);
 280         }
 281
 282         return ret;
 283 }
 284
 285 /* Print line separator (if not in JSON mode) */
 286 void print_nl(void)
 287 {
 288         if (!_jw)
 289                 printf("%s", _SL_);
 290 }