| /* |
| * jsmn.c |
| * Simple JSON parser |
| * |
| * Copyright (c) 2010 Serge A. Zaitsev |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| #include <stdlib.h> |
| |
| #include "jsmn.h" |
| |
| /** |
| * Allocates a fresh unused token from the token pull. |
| */ |
| static jsmntok_t *jsmn_alloc_token(jsmn_parser *parser, |
| jsmntok_t *tokens, int num_tokens) { |
| jsmntok_t *tok; |
| if (parser->toknext >= num_tokens) { |
| return NULL; |
| } |
| tok = &tokens[parser->toknext++]; |
| tok->start = tok->end = -1; |
| tok->size = 0; |
| #ifdef JSMN_PARENT_LINKS |
| tok->parent = -1; |
| #endif |
| return tok; |
| } |
| |
| /** |
| * Fills token type and boundaries. |
| */ |
| static void jsmn_fill_token(jsmntok_t *token, jsmntype_t type, |
| int start, int end) { |
| token->type = type; |
| token->start = start; |
| token->end = end; |
| token->size = 0; |
| } |
| |
| /** |
| * Fills next available token with JSON primitive. |
| */ |
| static jsmnerr_t jsmn_parse_primitive(jsmn_parser *parser, const char *js, |
| jsmntok_t *tokens, int num_tokens) { |
| jsmntok_t *token; |
| int start; |
| |
| start = parser->pos; |
| |
| for (; (parser->end > 0 && parser->pos < parser->end) && js[parser->pos] != '\0'; parser->pos++) { |
| switch (js[parser->pos]) { |
| #ifndef JSMN_STRICT |
| /* In strict mode primitive must be followed by "," or "}" or "]" */ |
| case ':': |
| #endif |
| case '\t' : case '\r' : case '\n' : case ' ' : |
| case ',' : case ']' : case '}' : |
| goto found; |
| default: |
| break; |
| } |
| if (js[parser->pos] < 32 || js[parser->pos] >= 127) { |
| parser->pos = start; |
| return JSMN_ERROR_INVAL; |
| } |
| } |
| #ifdef JSMN_STRICT |
| /* In strict mode primitive must be followed by a comma/object/array */ |
| parser->pos = start; |
| return JSMN_ERROR_PART; |
| #endif |
| |
| found: |
| token = jsmn_alloc_token(parser, tokens, num_tokens); |
| if (token == NULL) { |
| parser->pos = start; |
| return JSMN_ERROR_NOMEM; |
| } |
| jsmn_fill_token(token, JSMN_PRIMITIVE, start, parser->pos); |
| #ifdef JSMN_PARENT_LINKS |
| token->parent = parser->toksuper; |
| #endif |
| parser->pos--; |
| return JSMN_SUCCESS; |
| } |
| |
| /** |
| * Fills next token with JSON string. |
| */ |
| static jsmnerr_t jsmn_parse_string(jsmn_parser *parser, const char *js, |
| jsmntok_t *tokens, int num_tokens) { |
| jsmntok_t *token; |
| |
| int start = parser->pos; |
| |
| parser->pos++; |
| |
| /* Skip starting quote */ |
| for (; (parser->end > 0 && parser->pos < parser->end) && js[parser->pos] != '\0'; parser->pos++) { |
| char c = js[parser->pos]; |
| |
| /* Quote: end of string */ |
| if (c == '\"') { |
| token = jsmn_alloc_token(parser, tokens, num_tokens); |
| if (token == NULL) { |
| parser->pos = start; |
| return JSMN_ERROR_NOMEM; |
| } |
| jsmn_fill_token(token, JSMN_STRING, start+1, parser->pos); |
| #ifdef JSMN_PARENT_LINKS |
| token->parent = parser->toksuper; |
| #endif |
| return JSMN_SUCCESS; |
| } |
| |
| /* Backslash: Quoted symbol expected */ |
| if (c == '\\') { |
| parser->pos++; |
| if (parser->end > 0 && parser->pos >= parser->end) { |
| parser->pos = start; |
| return JSMN_ERROR_INVAL; |
| } |
| switch (js[parser->pos]) { |
| /* Allowed escaped symbols */ |
| case '\"': case '/' : case '\\' : case 'b' : |
| case 'f' : case 'r' : case 'n' : case 't' : |
| break; |
| /* Allows escaped symbol \uXXXX */ |
| case 'u': |
| /* TODO */ |
| break; |
| /* Unexpected symbol */ |
| default: |
| parser->pos = start; |
| return JSMN_ERROR_INVAL; |
| } |
| } |
| } |
| parser->pos = start; |
| return JSMN_ERROR_PART; |
| } |
| |
| /** |
| * Parse JSON string and fill tokens. |
| */ |
| jsmnerr_t jsmn_parse(jsmn_parser *parser, const char *js, unsigned int length, jsmntok_t *tokens, |
| unsigned int num_tokens) { |
| jsmnerr_t r; |
| int i; |
| jsmntok_t *token; |
| |
| parser->end = length; |
| |
| for (; (parser->end > 0 && parser->pos < parser->end) && js[parser->pos] != '\0'; parser->pos++) { |
| char c; |
| jsmntype_t type; |
| |
| c = js[parser->pos]; |
| switch (c) { |
| case '{': case '[': |
| token = jsmn_alloc_token(parser, tokens, num_tokens); |
| if (token == NULL) |
| return JSMN_ERROR_NOMEM; |
| if (parser->toksuper != -1) { |
| tokens[parser->toksuper].size++; |
| #ifdef JSMN_PARENT_LINKS |
| token->parent = parser->toksuper; |
| #endif |
| } |
| token->type = (c == '{' ? JSMN_OBJECT : JSMN_ARRAY); |
| token->start = parser->pos; |
| parser->toksuper = parser->toknext - 1; |
| break; |
| case '}': case ']': |
| type = (c == '}' ? JSMN_OBJECT : JSMN_ARRAY); |
| #ifdef JSMN_PARENT_LINKS |
| if (parser->toknext < 1) { |
| return JSMN_ERROR_INVAL; |
| } |
| token = &tokens[parser->toknext - 1]; |
| for (;;) { |
| if (token->start != -1 && token->end == -1) { |
| if (token->type != type) { |
| return JSMN_ERROR_INVAL; |
| } |
| token->end = parser->pos + 1; |
| parser->toksuper = token->parent; |
| break; |
| } |
| if (token->parent == -1) { |
| break; |
| } |
| token = &tokens[token->parent]; |
| } |
| #else |
| for (i = parser->toknext - 1; i >= 0; i--) { |
| token = &tokens[i]; |
| if (token->start != -1 && token->end == -1) { |
| if (token->type != type) { |
| return JSMN_ERROR_INVAL; |
| } |
| parser->toksuper = -1; |
| token->end = parser->pos + 1; |
| break; |
| } |
| } |
| /* Error if unmatched closing bracket */ |
| if (i == -1) return JSMN_ERROR_INVAL; |
| for (; i >= 0; i--) { |
| token = &tokens[i]; |
| if (token->start != -1 && token->end == -1) { |
| parser->toksuper = i; |
| break; |
| } |
| } |
| #endif |
| break; |
| case '\"': |
| r = jsmn_parse_string(parser, js, tokens, num_tokens); |
| if (r < 0) return r; |
| if (parser->toksuper != -1) |
| tokens[parser->toksuper].size++; |
| break; |
| case '\t' : case '\r' : case '\n' : case ':' : case ',': case ' ': |
| break; |
| #ifdef JSMN_STRICT |
| /* In strict mode primitives are: numbers and booleans */ |
| case '-': case '0': case '1' : case '2': case '3' : case '4': |
| case '5': case '6': case '7' : case '8': case '9': |
| case 't': case 'f': case 'n' : |
| #else |
| /* In non-strict mode every unquoted value is a primitive */ |
| default: |
| #endif |
| r = jsmn_parse_primitive(parser, js, tokens, num_tokens); |
| if (r < 0) return r; |
| if (parser->toksuper != -1) |
| tokens[parser->toksuper].size++; |
| break; |
| |
| #ifdef JSMN_STRICT |
| /* Unexpected char in strict mode */ |
| default: |
| return JSMN_ERROR_INVAL; |
| #endif |
| |
| } |
| } |
| |
| for (i = parser->toknext - 1; i >= 0; i--) { |
| /* Unmatched opened object or array */ |
| if (tokens[i].start != -1 && tokens[i].end == -1) { |
| return JSMN_ERROR_PART; |
| } |
| } |
| |
| return JSMN_SUCCESS; |
| } |
| |
| /** |
| * Creates a new parser based over a given buffer with an array of tokens |
| * available. |
| */ |
| void jsmn_init(jsmn_parser *parser) { |
| parser->pos = 0; |
| parser->end = 0; |
| parser->toknext = 0; |
| parser->toksuper = -1; |
| } |
| |