| 1 | #include <stdlib.h> |
| 2 | |
| 3 | #include "jsmn.h" |
| 4 | |
| 5 | /** |
| 6 | * Alloc token |
| 7 | * |
| 8 | * Allocates a fresh unused token from the token pull. |
| 9 | * |
| 10 | * @param parser the controller |
| 11 | * @param tokens the tokens I am working |
| 12 | * @param num_tokens the number total of tokens. |
| 13 | * |
| 14 | * @return it returns the next token to work. |
| 15 | */ |
| 16 | static jsmntok_t *jsmn_alloc_token(jsmn_parser *parser, |
| 17 | jsmntok_t *tokens, size_t num_tokens) { |
| 18 | jsmntok_t *tok; |
| 19 | if (parser->toknext >= num_tokens) { |
| 20 | return NULL; |
| 21 | } |
| 22 | tok = &tokens[parser->toknext++]; |
| 23 | tok->start = tok->end = -1; |
| 24 | tok->size = 0; |
| 25 | #ifdef JSMN_PARENT_LINKS |
| 26 | tok->parent = -1; |
| 27 | #endif |
| 28 | return tok; |
| 29 | } |
| 30 | |
| 31 | /** |
| 32 | * Fill Token |
| 33 | * |
| 34 | * Fills token type and boundaries. |
| 35 | * |
| 36 | * @param token the structure to set the values |
| 37 | * @param type is the token type |
| 38 | * @param start is the first position of the value |
| 39 | * @param end is the end of the value |
| 40 | */ |
| 41 | static void jsmn_fill_token(jsmntok_t *token, jsmntype_t type, |
| 42 | int start, int end) { |
| 43 | token->type = type; |
| 44 | token->start = start; |
| 45 | token->end = end; |
| 46 | token->size = 0; |
| 47 | } |
| 48 | |
| 49 | /** |
| 50 | * Parse primitive |
| 51 | * |
| 52 | * Fills next available token with JSON primitive. |
| 53 | * |
| 54 | * @param parser is the control structure |
| 55 | * @param js is the json string |
| 56 | * @param type is the token type |
| 57 | */ |
| 58 | static jsmnerr_t jsmn_parse_primitive(jsmn_parser *parser, const char *js, |
| 59 | size_t len, jsmntok_t *tokens, size_t num_tokens) { |
| 60 | jsmntok_t *token; |
| 61 | int start; |
| 62 | |
| 63 | start = parser->pos; |
| 64 | |
| 65 | for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) { |
| 66 | switch (js[parser->pos]) { |
| 67 | #ifndef JSMN_STRICT |
| 68 | /* In strict mode primitive must be followed by "," or "}" or "]" */ |
| 69 | case ':': |
| 70 | #endif |
| 71 | case '\t' : case '\r' : case '\n' : case ' ' : |
| 72 | case ',' : case ']' : case '}' : |
| 73 | goto found; |
| 74 | } |
| 75 | if (js[parser->pos] < 32 || js[parser->pos] >= 127) { |
| 76 | parser->pos = start; |
| 77 | return JSMN_ERROR_INVAL; |
| 78 | } |
| 79 | } |
| 80 | #ifdef JSMN_STRICT |
| 81 | /* In strict mode primitive must be followed by a comma/object/array */ |
| 82 | parser->pos = start; |
| 83 | return JSMN_ERROR_PART; |
| 84 | #endif |
| 85 | |
| 86 | found: |
| 87 | if (tokens == NULL) { |
| 88 | parser->pos--; |
| 89 | return 0; |
| 90 | } |
| 91 | token = jsmn_alloc_token(parser, tokens, num_tokens); |
| 92 | if (token == NULL) { |
| 93 | parser->pos = start; |
| 94 | return JSMN_ERROR_NOMEM; |
| 95 | } |
| 96 | jsmn_fill_token(token, JSMN_PRIMITIVE, start, parser->pos); |
| 97 | #ifdef JSMN_PARENT_LINKS |
| 98 | token->parent = parser->toksuper; |
| 99 | #endif |
| 100 | parser->pos--; |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * Parse string |
| 106 | * |
| 107 | * Fills next token with JSON string. |
| 108 | * |
| 109 | * @param parser is the control structure |
| 110 | * @param js is the json string |
| 111 | * @param len is the js length |
| 112 | * @param tokens is structure with the tokens mapped. |
| 113 | * @param num_tokens is the total number of tokens |
| 114 | * |
| 115 | * @return It returns 0 on success and another integer otherwise |
| 116 | */ |
| 117 | static jsmnerr_t jsmn_parse_string(jsmn_parser *parser, const char *js, |
| 118 | size_t len, jsmntok_t *tokens, size_t num_tokens) { |
| 119 | jsmntok_t *token; |
| 120 | |
| 121 | int start = parser->pos; |
| 122 | |
| 123 | parser->pos++; |
| 124 | |
| 125 | /* Skip starting quote */ |
| 126 | for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) { |
| 127 | char c = js[parser->pos]; |
| 128 | |
| 129 | /* Quote: end of string */ |
| 130 | if (c == '\"') { |
| 131 | if (tokens == NULL) { |
| 132 | return 0; |
| 133 | } |
| 134 | token = jsmn_alloc_token(parser, tokens, num_tokens); |
| 135 | if (token == NULL) { |
| 136 | parser->pos = start; |
| 137 | return JSMN_ERROR_NOMEM; |
| 138 | } |
| 139 | jsmn_fill_token(token, JSMN_STRING, start+1, parser->pos); |
| 140 | #ifdef JSMN_PARENT_LINKS |
| 141 | token->parent = parser->toksuper; |
| 142 | #endif |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | /* Backslash: Quoted symbol expected */ |
| 147 | if (c == '\\') { |
| 148 | parser->pos++; |
| 149 | switch (js[parser->pos]) { |
| 150 | /* Allowed escaped symbols */ |
| 151 | case '\"': case '/' : case '\\' : case 'b' : |
| 152 | case 'f' : case 'r' : case 'n' : case 't' : |
| 153 | break; |
| 154 | /* Allows escaped symbol \uXXXX */ |
| 155 | case 'u': |
| 156 | parser->pos++; |
| 157 | int i = 0; |
| 158 | for(; i < 4 && js[parser->pos] != '\0'; i++) { |
| 159 | /* If it isn't a hex character we have an error */ |
| 160 | if(!((js[parser->pos] >= 48 && js[parser->pos] <= 57) || /* 0-9 */ |
| 161 | (js[parser->pos] >= 65 && js[parser->pos] <= 70) || /* A-F */ |
| 162 | (js[parser->pos] >= 97 && js[parser->pos] <= 102))) { /* a-f */ |
| 163 | parser->pos = start; |
| 164 | return JSMN_ERROR_INVAL; |
| 165 | } |
| 166 | parser->pos++; |
| 167 | } |
| 168 | parser->pos--; |
| 169 | break; |
| 170 | /* Unexpected symbol */ |
| 171 | default: |
| 172 | parser->pos = start; |
| 173 | return JSMN_ERROR_INVAL; |
| 174 | } |
| 175 | } |
| 176 | } |
| 177 | parser->pos = start; |
| 178 | return JSMN_ERROR_PART; |
| 179 | } |
| 180 | |
| 181 | /** |
| 182 | * JSMN Parse |
| 183 | * |
| 184 | * Parse JSON string and fill tokens. |
| 185 | * |
| 186 | * @param parser the auxiliary vector used to parser |
| 187 | * @param js the string to parse |
| 188 | * @param len the string length |
| 189 | * @param tokens the place to map the tokens |
| 190 | * @param num_tokens the number of tokens present in the tokens structure. |
| 191 | * |
| 192 | * @return It returns the number of tokens present in the string on success or a negative number otherwise |
| 193 | */ |
| 194 | jsmnerr_t jsmn_parse(jsmn_parser *parser, const char *js, size_t len, |
| 195 | jsmntok_t *tokens, unsigned int num_tokens) { |
| 196 | jsmnerr_t r; |
| 197 | int i; |
| 198 | jsmntok_t *token; |
| 199 | int count = 0; |
| 200 | |
| 201 | for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) { |
| 202 | char c; |
| 203 | jsmntype_t type; |
| 204 | |
| 205 | c = js[parser->pos]; |
| 206 | switch (c) { |
| 207 | case '{': case '[': |
| 208 | count++; |
| 209 | if (tokens == NULL) { |
| 210 | break; |
| 211 | } |
| 212 | token = jsmn_alloc_token(parser, tokens, num_tokens); |
| 213 | if (token == NULL) |
| 214 | return JSMN_ERROR_NOMEM; |
| 215 | if (parser->toksuper != -1) { |
| 216 | tokens[parser->toksuper].size++; |
| 217 | #ifdef JSMN_PARENT_LINKS |
| 218 | token->parent = parser->toksuper; |
| 219 | #endif |
| 220 | } |
| 221 | token->type = (c == '{' ? JSMN_OBJECT : JSMN_ARRAY); |
| 222 | token->start = parser->pos; |
| 223 | parser->toksuper = parser->toknext - 1; |
| 224 | break; |
| 225 | case '}': case ']': |
| 226 | if (tokens == NULL) |
| 227 | break; |
| 228 | type = (c == '}' ? JSMN_OBJECT : JSMN_ARRAY); |
| 229 | #ifdef JSMN_PARENT_LINKS |
| 230 | if (parser->toknext < 1) { |
| 231 | return JSMN_ERROR_INVAL; |
| 232 | } |
| 233 | token = &tokens[parser->toknext - 1]; |
| 234 | for (;;) { |
| 235 | if (token->start != -1 && token->end == -1) { |
| 236 | if (token->type != type) { |
| 237 | return JSMN_ERROR_INVAL; |
| 238 | } |
| 239 | token->end = parser->pos + 1; |
| 240 | parser->toksuper = token->parent; |
| 241 | break; |
| 242 | } |
| 243 | if (token->parent == -1) { |
| 244 | break; |
| 245 | } |
| 246 | token = &tokens[token->parent]; |
| 247 | } |
| 248 | #else |
| 249 | for (i = parser->toknext - 1; i >= 0; i--) { |
| 250 | token = &tokens[i]; |
| 251 | if (token->start != -1 && token->end == -1) { |
| 252 | if (token->type != type) { |
| 253 | return JSMN_ERROR_INVAL; |
| 254 | } |
| 255 | parser->toksuper = -1; |
| 256 | token->end = parser->pos + 1; |
| 257 | break; |
| 258 | } |
| 259 | } |
| 260 | /* Error if unmatched closing bracket */ |
| 261 | if (i == -1) return JSMN_ERROR_INVAL; |
| 262 | for (; i >= 0; i--) { |
| 263 | token = &tokens[i]; |
| 264 | if (token->start != -1 && token->end == -1) { |
| 265 | parser->toksuper = i; |
| 266 | break; |
| 267 | } |
| 268 | } |
| 269 | #endif |
| 270 | break; |
| 271 | case '\"': |
| 272 | r = jsmn_parse_string(parser, js, len, tokens, num_tokens); |
| 273 | if (r < 0) return r; |
| 274 | count++; |
| 275 | if (parser->toksuper != -1 && tokens != NULL) |
| 276 | tokens[parser->toksuper].size++; |
| 277 | break; |
| 278 | case '\t' : case '\r' : case '\n' : case ':' : case ',': case ' ': |
| 279 | break; |
| 280 | #ifdef JSMN_STRICT |
| 281 | /* In strict mode primitives are: numbers and booleans */ |
| 282 | case '-': case '0': case '1' : case '2': case '3' : case '4': |
| 283 | case '5': case '6': case '7' : case '8': case '9': |
| 284 | case 't': case 'f': case 'n' : |
| 285 | #else |
| 286 | /* In non-strict mode every unquoted value is a primitive */ |
| 287 | default: |
| 288 | #endif |
| 289 | r = jsmn_parse_primitive(parser, js, len, tokens, num_tokens); |
| 290 | if (r < 0) return r; |
| 291 | count++; |
| 292 | if (parser->toksuper != -1 && tokens != NULL) |
| 293 | tokens[parser->toksuper].size++; |
| 294 | break; |
| 295 | |
| 296 | #ifdef JSMN_STRICT |
| 297 | /* Unexpected char in strict mode */ |
| 298 | default: |
| 299 | return JSMN_ERROR_INVAL; |
| 300 | #endif |
| 301 | } |
| 302 | } |
| 303 | |
| 304 | if (tokens) { |
| 305 | for (i = parser->toknext - 1; i >= 0; i--) { |
| 306 | /* Unmatched opened object or array */ |
| 307 | if (tokens[i].start != -1 && tokens[i].end == -1) { |
| 308 | return JSMN_ERROR_PART; |
| 309 | } |
| 310 | } |
| 311 | } |
| 312 | |
| 313 | return count; |
| 314 | } |
| 315 | |
| 316 | /** |
| 317 | * JSMN Init |
| 318 | * |
| 319 | * Creates a new parser based over a given buffer with an array of tokens |
| 320 | * available. |
| 321 | * |
| 322 | * @param parser is the structure with values to reset |
| 323 | */ |
| 324 | void jsmn_init(jsmn_parser *parser) { |
| 325 | parser->pos = 0; |
| 326 | parser->toknext = 0; |
| 327 | parser->toksuper = -1; |
| 328 | } |