/* * 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. * * Slightly modified by AK to not assume 0 terminated input. */ #include <stdlib.h> #include "jsmn.h" /* * Allocates a fresh unused token from the token pool. */ static jsmntok_t *jsmn_alloc_token(jsmn_parser *parser, jsmntok_t *tokens, size_t num_tokens) { jsmntok_t *tok; if ((unsigned)parser->toknext >= num_tokens) return NULL; tok = &tokens[parser->toknext++]; tok->start = tok->end = -1; tok->size = 0; 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, size_t len, jsmntok_t *tokens, size_t num_tokens) { jsmntok_t *token; int start; start = parser->pos; for (; parser->pos < len; 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); parser->pos--; /* parent sees closing brackets */ return JSMN_SUCCESS; } /* * Fills next token with JSON string. */ static jsmnerr_t jsmn_parse_string(jsmn_parser *parser, const char *js, size_t len, jsmntok_t *tokens, size_t num_tokens) { jsmntok_t *token; int start = parser->pos; /* Skip starting quote */ parser->pos++; for (; parser->pos < len; 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); return JSMN_SUCCESS; } /* Backslash: Quoted symbol expected */ if (c == '\\') { parser->pos++; 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, size_t len, jsmntok_t *tokens, unsigned int num_tokens) { jsmnerr_t r; int i; jsmntok_t *token; for (; parser->pos < len; 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++; 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); 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; } } break; case '\"': r = jsmn_parse_string(parser, js, len, 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. */ /*FALL THROUGH */ default: #endif r = jsmn_parse_primitive(parser, js, len, 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->toknext = 0; parser->toksuper = -1; } const char *jsmn_strerror(jsmnerr_t err) { switch (err) { case JSMN_ERROR_NOMEM: return "No enough tokens"; case JSMN_ERROR_INVAL: return "Invalid character inside JSON string"; case JSMN_ERROR_PART: return "The string is not a full JSON packet, more bytes expected"; case JSMN_SUCCESS: return "Success"; default: return "Unknown json error"; } }