src/dump.c

   1 /*
   2  * Copyright (c) 2009-2011 Petri Lehtinen <petri@digip.org>
   3  *
   4  * Jansson is free software; you can redistribute it and/or modify
   5  * it under the terms of the MIT license. See LICENSE for details.
   6  */
   7
   8 #define _GNU_SOURCE
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <assert.h>
  13
  14 #include <jansson.h>
  15 #include "jansson_private.h"
  16 #include "strbuffer.h"
  17 #include "utf.h"
  18
  19 #define MAX_INTEGER_STR_LENGTH  100
  20 #define MAX_REAL_STR_LENGTH     100
  21
  22 struct string
  23 {
  24     char *buffer;
  25     int length;
  26     int size;
  27 };
  28
  29 static int dump_to_strbuffer(const char *buffer, size_t size, void *data)
  30 {
  31     return strbuffer_append_bytes((strbuffer_t *)data, buffer, size);
  32 }
  33
  34 static int dump_to_file(const char *buffer, size_t size, void *data)
  35 {
  36     FILE *dest = (FILE *)data;
  37     if(fwrite(buffer, size, 1, dest) != 1)
  38         return -1;
  39     return 0;
  40 }
  41
  42 /* 32 spaces (the maximum indentation size) */
  43 static char whitespace[] = "                                ";
  44
  45 static int dump_indent(size_t flags, int depth, int space, json_dump_callback_t dump, void *data)
  46 {
  47     if(JSON_INDENT(flags) > 0)
  48     {
  49         int i, ws_count = JSON_INDENT(flags);
  50
  51         if(dump("\n", 1, data))
  52             return -1;
  53
  54         for(i = 0; i < depth; i++)
  55         {
  56             if(dump(whitespace, ws_count, data))
  57                 return -1;
  58         }
  59     }
  60     else if(space && !(flags & JSON_COMPACT))
  61     {
  62         return dump(" ", 1, data);
  63     }
  64     return 0;
  65 }
  66
  67 static int dump_string(const char *str, int ascii, json_dump_callback_t dump, void *data)
  68 {
  69     const char *pos, *end;
  70     int32_t codepoint;
  71
  72     if(dump("\"", 1, data))
  73         return -1;
  74
  75     end = pos = str;
  76     while(1)
  77     {
  78         const char *text;
  79         char seq[13];
  80         int length;
  81
  82         while(*end)
  83         {
  84             end = utf8_iterate(pos, &codepoint);
  85             if(!end)
  86                 return -1;
  87
  88             /* mandatory escape or control char */
  89             if(codepoint == '\\' || codepoint == '"' || codepoint < 0x20)
  90                 break;
  91
  92             /* non-ASCII */
  93             if(ascii && codepoint > 0x7F)
  94                 break;
  95
  96             pos = end;
  97         }
  98
  99         if(pos != str) {
 100             if(dump(str, pos - str, data))
 101                 return -1;
 102         }
 103
 104         if(end == pos)
 105             break;
 106
 107         /* handle \, ", and control codes */
 108         length = 2;
 109         switch(codepoint)
 110         {
 111             case '\\': text = "\\\\"; break;
 112             case '\"': text = "\\\""; break;
 113             case '\b': text = "\\b"; break;
 114             case '\f': text = "\\f"; break;
 115             case '\n': text = "\\n"; break;
 116             case '\r': text = "\\r"; break;
 117             case '\t': text = "\\t"; break;
 118             default:
 119             {
 120                 /* codepoint is in BMP */
 121                 if(codepoint < 0x10000)
 122                 {
 123                     sprintf(seq, "\\u%04x", codepoint);
 124                     length = 6;
 125                 }
 126
 127                 /* not in BMP -> construct a UTF-16 surrogate pair */
 128                 else
 129                 {
 130                     int32_t first, last;
 131
 132                     codepoint -= 0x10000;
 133                     first = 0xD800 | ((codepoint & 0xffc00) >> 10);
 134                     last = 0xDC00 | (codepoint & 0x003ff);
 135
 136                     sprintf(seq, "\\u%04x\\u%04x", first, last);
 137                     length = 12;
 138                 }
 139
 140                 text = seq;
 141                 break;
 142             }
 143         }
 144
 145         if(dump(text, length, data))
 146             return -1;
 147
 148         str = pos = end;
 149     }
 150
 151     return dump("\"", 1, data);
 152 }
 153
 154 static int object_key_compare_keys(const void *key1, const void *key2)
 155 {
 156     return strcmp((*(const object_key_t **)key1)->key,
 157                   (*(const object_key_t **)key2)->key);
 158 }
 159
 160 static int object_key_compare_serials(const void *key1, const void *key2)
 161 {
 162     return (*(const object_key_t **)key1)->serial -
 163            (*(const object_key_t **)key2)->serial;
 164 }
 165
 166 static int do_dump(const json_t *json, size_t flags, int depth,
 167                    json_dump_callback_t dump, void *data)
 168 {
 169     int ascii = flags & JSON_ENSURE_ASCII ? 1 : 0;
 170
 171     switch(json_typeof(json)) {
 172         case JSON_NULL:
 173             return dump("null", 4, data);
 174
 175         case JSON_TRUE:
 176             return dump("true", 4, data);
 177
 178         case JSON_FALSE:
 179             return dump("false", 5, data);
 180
 181         case JSON_INTEGER:
 182         {
 183             char buffer[MAX_INTEGER_STR_LENGTH];
 184             int size;
 185
 186             size = snprintf(buffer, MAX_INTEGER_STR_LENGTH,
 187                             "%" JSON_INTEGER_FORMAT,
 188                             json_integer_value(json));
 189             if(size >= MAX_INTEGER_STR_LENGTH)
 190                 return -1;
 191
 192             return dump(buffer, size, data);
 193         }
 194
 195         case JSON_REAL:
 196         {
 197             char buffer[MAX_REAL_STR_LENGTH];
 198             int size;
 199             double value = json_real_value(json);
 200
 201             size = jsonp_dtostr(buffer, MAX_REAL_STR_LENGTH, value);
 202             if(size < 0)
 203                 return -1;
 204
 205             return dump(buffer, size, data);
 206         }
 207
 208         case JSON_STRING:
 209             return dump_string(json_string_value(json), ascii, dump, data);
 210
 211         case JSON_ARRAY:
 212         {
 213             int i;
 214             int n;
 215             json_array_t *array;
 216
 217             /* detect circular references */
 218             array = json_to_array(json);
 219             if(array->visited)
 220                 goto array_error;
 221             array->visited = 1;
 222
 223             n = json_array_size(json);
 224
 225             if(dump("[", 1, data))
 226                 goto array_error;
 227             if(n == 0) {
 228                 array->visited = 0;
 229                 return dump("]", 1, data);
 230             }
 231             if(dump_indent(flags, depth + 1, 0, dump, data))
 232                 goto array_error;
 233
 234             for(i = 0; i < n; ++i) {
 235                 if(do_dump(json_array_get(json, i), flags, depth + 1,
 236                            dump, data))
 237                     goto array_error;
 238
 239                 if(i < n - 1)
 240                 {
 241                     if(dump(",", 1, data) ||
 242                        dump_indent(flags, depth + 1, 1, dump, data))
 243                         goto array_error;
 244                 }
 245                 else
 246                 {
 247                     if(dump_indent(flags, depth, 0, dump, data))
 248                         goto array_error;
 249                 }
 250             }
 251
 252             array->visited = 0;
 253             return dump("]", 1, data);
 254
 255         array_error:
 256             array->visited = 0;
 257             return -1;
 258         }
 259
 260         case JSON_OBJECT:
 261         {
 262             json_object_t *object;
 263             void *iter;
 264             const char *separator;
 265             int separator_length;
 266
 267             if(flags & JSON_COMPACT) {
 268                 separator = ":";
 269                 separator_length = 1;
 270             }
 271             else {
 272                 separator = ": ";
 273                 separator_length = 2;
 274             }
 275
 276             /* detect circular references */
 277             object = json_to_object(json);
 278             if(object->visited)
 279                 goto object_error;
 280             object->visited = 1;
 281
 282             iter = json_object_iter((json_t *)json);
 283
 284             if(dump("{", 1, data))
 285                 goto object_error;
 286             if(!iter) {
 287                 object->visited = 0;
 288                 return dump("}", 1, data);
 289             }
 290             if(dump_indent(flags, depth + 1, 0, dump, data))
 291                 goto object_error;
 292
 293             if(flags & JSON_SORT_KEYS || flags & JSON_PRESERVE_ORDER)
 294             {
 295                 const object_key_t **keys;
 296                 size_t size, i;
 297                 int (*cmp_func)(const void *, const void *);
 298
 299                 size = json_object_size(json);
 300                 keys = jsonp_malloc(size * sizeof(object_key_t *));
 301                 if(!keys)
 302                     goto object_error;
 303
 304                 i = 0;
 305                 while(iter)
 306                 {
 307                     keys[i] = jsonp_object_iter_fullkey(iter);
 308                     iter = json_object_iter_next((json_t *)json, iter);
 309                     i++;
 310                 }
 311                 assert(i == size);
 312
 313                 if(flags & JSON_SORT_KEYS)
 314                     cmp_func = object_key_compare_keys;
 315                 else
 316                     cmp_func = object_key_compare_serials;
 317
 318                 qsort(keys, size, sizeof(object_key_t *), cmp_func);
 319
 320                 for(i = 0; i < size; i++)
 321                 {
 322                     const char *key;
 323                     json_t *value;
 324
 325                     key = keys[i]->key;
 326                     value = json_object_get(json, key);
 327                     assert(value);
 328
 329                     dump_string(key, ascii, dump, data);
 330                     if(dump(separator, separator_length, data) ||
 331                        do_dump(value, flags, depth + 1, dump, data))
 332                     {
 333                         jsonp_free(keys);
 334                         goto object_error;
 335                     }
 336
 337                     if(i < size - 1)
 338                     {
 339                         if(dump(",", 1, data) ||
 340                            dump_indent(flags, depth + 1, 1, dump, data))
 341                         {
 342                             jsonp_free(keys);
 343                             goto object_error;
 344                         }
 345                     }
 346                     else
 347                     {
 348                         if(dump_indent(flags, depth, 0, dump, data))
 349                         {
 350                             jsonp_free(keys);
 351                             goto object_error;
 352                         }
 353                     }
 354                 }
 355
 356                 jsonp_free(keys);
 357             }
 358             else
 359             {
 360                 /* Don't sort keys */
 361
 362                 while(iter)
 363                 {
 364                     void *next = json_object_iter_next((json_t *)json, iter);
 365
 366                     dump_string(json_object_iter_key(iter), ascii, dump, data);
 367                     if(dump(separator, separator_length, data) ||
 368                        do_dump(json_object_iter_value(iter), flags, depth + 1,
 369                                dump, data))
 370                         goto object_error;
 371
 372                     if(next)
 373                     {
 374                         if(dump(",", 1, data) ||
 375                            dump_indent(flags, depth + 1, 1, dump, data))
 376                             goto object_error;
 377                     }
 378                     else
 379                     {
 380                         if(dump_indent(flags, depth, 0, dump, data))
 381                             goto object_error;
 382                     }
 383
 384                     iter = next;
 385                 }
 386             }
 387
 388             object->visited = 0;
 389             return dump("}", 1, data);
 390
 391         object_error:
 392             object->visited = 0;
 393             return -1;
 394         }
 395
 396         default:
 397             /* not reached */
 398             return -1;
 399     }
 400 }
 401
 402 char *json_dumps(const json_t *json, size_t flags)
 403 {
 404     strbuffer_t strbuff;
 405     char *result;
 406
 407     if(strbuffer_init(&strbuff))
 408         return NULL;
 409
 410     if(json_dump_callback(json, dump_to_strbuffer, (void *)&strbuff, flags))
 411         result = NULL;
 412     else
 413         result = jsonp_strdup(strbuffer_value(&strbuff));
 414
 415     strbuffer_close(&strbuff);
 416     return result;
 417 }
 418
 419 int json_dumpf(const json_t *json, FILE *output, size_t flags)
 420 {
 421     return json_dump_callback(json, dump_to_file, (void *)output, flags);
 422 }
 423
 424 int json_dump_file(const json_t *json, const char *path, size_t flags)
 425 {
 426     int result;
 427
 428     FILE *output = fopen(path, "w");
 429     if(!output)
 430         return -1;
 431
 432     result = json_dumpf(json, output, flags);
 433
 434     fclose(output);
 435     return result;
 436 }
 437
 438 int json_dump_callback(const json_t *json, json_dump_callback_t callback, void *data, size_t flags)
 439 {
 440     if(!(flags & JSON_ENCODE_ANY)) {
 441         if(!json_is_array(json) && !json_is_object(json))
 442            return -1;
 443     }
 444
 445     return do_dump(json, flags, 0, callback, data);
 446 }