/* vim: set et ts=3 sw=3 sts=3 ft=c: * * Copyright (C) 2012, 2013, 2014 James McLaughlin et al. All rights reserved. * https://github.com/udp/json-parser * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "json.h" #ifdef _MSC_VER #ifndef _CRT_SECURE_NO_WARNINGS #define _CRT_SECURE_NO_WARNINGS #endif #endif #define JSON_ALLOW_TRAILING_GARBAGE 1 const struct _json_value json_value_none; #include #include #include #include #include #if UINT_MAX >= 0x10FFFF typedef unsigned int json_uchar; #else typedef unsigned long json_uchar; #endif static unsigned char hex_value (json_char c) { if (isdigit(c)) return c - '0'; switch (c) { case 'a': case 'A': return 0x0A; case 'b': case 'B': return 0x0B; case 'c': case 'C': return 0x0C; case 'd': case 'D': return 0x0D; case 'e': case 'E': return 0x0E; case 'f': case 'F': return 0x0F; default: return 0xFF; } } typedef struct { unsigned long used_memory; unsigned int uint_max; unsigned long ulong_max; json_settings settings; int first_pass; const json_char * ptr; unsigned int cur_line, cur_col; } json_state; static void * default_alloc (size_t size, int zero, void * user_data) { return zero ? calloc (1, size) : malloc (size); } static void default_free (void * ptr, void * user_data) { free (ptr); } static void * json_alloc (json_state * state, unsigned long size, int zero) { if ((state->ulong_max - state->used_memory) < size) return 0; if (state->settings.max_memory && (state->used_memory += size) > state->settings.max_memory) { return 0; } return state->settings.mem_alloc (size, zero, state->settings.user_data); } static int new_value (json_state * state, json_value ** top, json_value ** root, json_value ** alloc, json_type type) { json_value * value; int values_size; if (!state->first_pass) { value = *top = *alloc; *alloc = (*alloc)->_reserved.next_alloc; if (!*root) *root = value; switch (value->type) { case json_array: if (value->u.array.length == 0) break; if (! (value->u.array.values = (json_value **) json_alloc (state, value->u.array.length * sizeof (json_value *), 0)) ) { return 0; } value->u.array.length = 0; break; case json_object: if (value->u.object.length == 0) break; values_size = sizeof (*value->u.object.values) * value->u.object.length; if (! (value->u.object.values = (json_object_entry *) json_alloc (state, values_size + ((unsigned long) value->u.object.values), 0)) ) { return 0; } value->_reserved.object_mem = (*(char **) &value->u.object.values) + values_size; value->u.object.length = 0; break; case json_string: if (! (value->u.string.ptr = (json_char *) json_alloc (state, (value->u.string.length + 1) * sizeof (json_char), 0)) ) { return 0; } value->u.string.length = 0; break; default: break; }; return 1; } if (! (value = (json_value *) json_alloc (state, sizeof (json_value) + state->settings.value_extra, 1))) { return 0; } if (!*root) *root = value; value->type = type; value->parent = *top; #ifdef JSON_TRACK_SOURCE value->line = state->cur_line; value->col = state->cur_col; #endif if (*alloc) (*alloc)->_reserved.next_alloc = value; *alloc = *top = value; return 1; } #define whitespace \ case '\n': ++ state.cur_line; state.cur_col = 0; \ case ' ': case '\t': case '\r' #define string_add(b) \ do { if (!state.first_pass) string [string_length] = b; ++ string_length; } while (0); #define line_and_col \ state.cur_line, state.cur_col static const long flag_next = 1 << 0, flag_reproc = 1 << 1, flag_need_comma = 1 << 2, flag_seek_value = 1 << 3, flag_escaped = 1 << 4, flag_string = 1 << 5, flag_need_colon = 1 << 6, flag_done = 1 << 7, flag_num_negative = 1 << 8, flag_num_zero = 1 << 9, flag_num_e = 1 << 10, flag_num_e_got_sign = 1 << 11, flag_num_e_negative = 1 << 12, flag_line_comment = 1 << 13, flag_block_comment = 1 << 14; json_value * json_parse_ex (json_settings * settings, const json_char * json, size_t length, char * error_buf) { json_char error [json_error_max]; const json_char * end; json_value * top, * root, * alloc = 0; json_state state = { 0 }; long flags; long num_digits = 0, num_e = 0; json_int_t num_fraction = 0; /* Skip UTF-8 BOM */ if (length >= 3 && ((unsigned char) json [0]) == 0xEF && ((unsigned char) json [1]) == 0xBB && ((unsigned char) json [2]) == 0xBF) { json += 3; length -= 3; } error[0] = '\0'; end = (json + length); memcpy (&state.settings, settings, sizeof (json_settings)); if (!state.settings.mem_alloc) state.settings.mem_alloc = default_alloc; if (!state.settings.mem_free) state.settings.mem_free = default_free; memset (&state.uint_max, 0xFF, sizeof (state.uint_max)); memset (&state.ulong_max, 0xFF, sizeof (state.ulong_max)); state.uint_max -= 8; /* limit of how much can be added before next check */ state.ulong_max -= 8; for (state.first_pass = 1; state.first_pass >= 0; -- state.first_pass) { json_uchar uchar; unsigned char uc_b1, uc_b2, uc_b3, uc_b4; json_char * string = 0; unsigned int string_length = 0; top = root = 0; flags = flag_seek_value; state.cur_line = 1; for (state.ptr = json ;; ++ state.ptr) { json_char b = (state.ptr == end ? 0 : *state.ptr); if (flags & flag_string) { if (!b) { sprintf (error, "Unexpected EOF in string (at %d:%d)", line_and_col); goto e_failed; } if (string_length > state.uint_max) goto e_overflow; if (flags & flag_escaped) { flags &= ~ flag_escaped; switch (b) { case 'b': string_add ('\b'); break; case 'f': string_add ('\f'); break; case 'n': string_add ('\n'); break; case 'r': string_add ('\r'); break; case 't': string_add ('\t'); break; case 'u': if (end - state.ptr <= 4 || (uc_b1 = hex_value (*++ state.ptr)) == 0xFF || (uc_b2 = hex_value (*++ state.ptr)) == 0xFF || (uc_b3 = hex_value (*++ state.ptr)) == 0xFF || (uc_b4 = hex_value (*++ state.ptr)) == 0xFF) { sprintf (error, "Invalid character value `%c` (at %d:%d)", b, line_and_col); goto e_failed; } uc_b1 = (uc_b1 << 4) | uc_b2; uc_b2 = (uc_b3 << 4) | uc_b4; uchar = ((json_uchar)uc_b1 << 8) | uc_b2; if ((uchar & 0xF800) == 0xD800) { json_uchar uchar2; if (end - state.ptr <= 6 || (*++ state.ptr) != '\\' || (*++ state.ptr) != 'u' || (uc_b1 = hex_value (*++ state.ptr)) == 0xFF || (uc_b2 = hex_value (*++ state.ptr)) == 0xFF || (uc_b3 = hex_value (*++ state.ptr)) == 0xFF || (uc_b4 = hex_value (*++ state.ptr)) == 0xFF) { sprintf (error, "Invalid character value `%c` (at %d:%d)", b, line_and_col); goto e_failed; } uc_b1 = (uc_b1 << 4) | uc_b2; uc_b2 = (uc_b3 << 4) | uc_b4; uchar2 = ((json_uchar)uc_b1 << 8) | uc_b2; uchar = 0x010000 | ((uchar & 0x3FF) << 10) | (uchar2 & 0x3FF); } if (sizeof (json_char) >= sizeof (json_uchar) || (uchar <= 0x7F)) { string_add ((json_char) uchar); break; } if (uchar <= 0x7FF) { if (state.first_pass) string_length += 2; else { string [string_length ++] = 0xC0 | (uchar >> 6); string [string_length ++] = 0x80 | (uchar & 0x3F); } break; } if (uchar <= 0xFFFF) { if (state.first_pass) string_length += 3; else { string [string_length ++] = 0xE0 | (uchar >> 12); string [string_length ++] = 0x80 | ((uchar >> 6) & 0x3F); string [string_length ++] = 0x80 | (uchar & 0x3F); } break; } if (state.first_pass) string_length += 4; else { string [string_length ++] = 0xF0 | (uchar >> 18); string [string_length ++] = 0x80 | ((uchar >> 12) & 0x3F); string [string_length ++] = 0x80 | ((uchar >> 6) & 0x3F); string [string_length ++] = 0x80 | (uchar & 0x3F); } break; default: string_add (b); }; continue; } if (b == '\\') { flags |= flag_escaped; continue; } if (b == '"') { if (!state.first_pass) string [string_length] = 0; flags &= ~ flag_string; string = 0; switch (top->type) { case json_string: top->u.string.length = string_length; flags |= flag_next; break; case json_object: if (state.first_pass) (*(json_char **) &top->u.object.values) += string_length + 1; else { top->u.object.values [top->u.object.length].name = (json_char *) top->_reserved.object_mem; top->u.object.values [top->u.object.length].name_length = string_length; (*(json_char **) &top->_reserved.object_mem) += string_length + 1; } flags |= flag_seek_value | flag_need_colon; continue; default: break; }; } else { string_add (b); continue; } } if (state.settings.settings & json_enable_comments) { if (flags & (flag_line_comment | flag_block_comment)) { if (flags & flag_line_comment) { if (b == '\r' || b == '\n' || !b) { flags &= ~ flag_line_comment; -- state.ptr; /* so null can be reproc'd */ } continue; } if (flags & flag_block_comment) { if (!b) { sprintf (error, "%d:%d: Unexpected EOF in block comment", line_and_col); goto e_failed; } if (b == '*' && state.ptr < (end - 1) && state.ptr [1] == '/') { flags &= ~ flag_block_comment; ++ state.ptr; /* skip closing sequence */ } continue; } } else if (b == '/') { if (! (flags & (flag_seek_value | flag_done)) && top->type != json_object) { sprintf (error, "%d:%d: Comment not allowed here", line_and_col); goto e_failed; } if (++ state.ptr == end) { sprintf (error, "%d:%d: EOF unexpected", line_and_col); goto e_failed; } switch (b = *state.ptr) { case '/': flags |= flag_line_comment; continue; case '*': flags |= flag_block_comment; continue; default: sprintf (error, "%d:%d: Unexpected `%c` in comment opening sequence", line_and_col, b); goto e_failed; }; } } if (flags & flag_done) { if (!b) break; #ifndef JSON_ALLOW_TRAILING_GARBAGE switch (b) { whitespace: continue; default: sprintf (error, "%d:%d: Trailing garbage: `%c`", state.cur_line, state.cur_col, b); goto e_failed; }; #else continue; #endif } if (flags & flag_seek_value) { switch (b) { whitespace: continue; case ']': if (top && top->type == json_array) flags = (flags & ~ (flag_need_comma | flag_seek_value)) | flag_next; else { sprintf (error, "%d:%d: Unexpected ]", line_and_col); goto e_failed; } break; default: if (flags & flag_need_comma) { if (b == ',') { flags &= ~ flag_need_comma; continue; } else { sprintf (error, "%d:%d: Expected , before %c", state.cur_line, state.cur_col, b); goto e_failed; } } if (flags & flag_need_colon) { if (b == ':') { flags &= ~ flag_need_colon; continue; } else { sprintf (error, "%d:%d: Expected : before %c", state.cur_line, state.cur_col, b); goto e_failed; } } flags &= ~ flag_seek_value; switch (b) { case '{': if (!new_value (&state, &top, &root, &alloc, json_object)) goto e_alloc_failure; continue; case '[': if (!new_value (&state, &top, &root, &alloc, json_array)) goto e_alloc_failure; flags |= flag_seek_value; continue; case '"': if (!new_value (&state, &top, &root, &alloc, json_string)) goto e_alloc_failure; flags |= flag_string; string = top->u.string.ptr; string_length = 0; continue; case 't': if ((end - state.ptr) < 3 || *(++ state.ptr) != 'r' || *(++ state.ptr) != 'u' || *(++ state.ptr) != 'e') { goto e_unknown_value; } if (!new_value (&state, &top, &root, &alloc, json_boolean)) goto e_alloc_failure; top->u.boolean = 1; flags |= flag_next; break; case 'f': if ((end - state.ptr) < 4 || *(++ state.ptr) != 'a' || *(++ state.ptr) != 'l' || *(++ state.ptr) != 's' || *(++ state.ptr) != 'e') { goto e_unknown_value; } if (!new_value (&state, &top, &root, &alloc, json_boolean)) goto e_alloc_failure; flags |= flag_next; break; case 'n': if ((end - state.ptr) < 3 || *(++ state.ptr) != 'u' || *(++ state.ptr) != 'l' || *(++ state.ptr) != 'l') { goto e_unknown_value; } if (!new_value (&state, &top, &root, &alloc, json_null)) goto e_alloc_failure; flags |= flag_next; break; default: if (isdigit (b) || b == '-') { if (!new_value (&state, &top, &root, &alloc, json_integer)) goto e_alloc_failure; if (!state.first_pass) { while (isdigit (b) || b == '+' || b == '-' || b == 'e' || b == 'E' || b == '.') { if ( (++ state.ptr) == end) { b = 0; break; } b = *state.ptr; } flags |= flag_next | flag_reproc; break; } flags &= ~ (flag_num_negative | flag_num_e | flag_num_e_got_sign | flag_num_e_negative | flag_num_zero); num_digits = 0; num_fraction = 0; num_e = 0; if (b != '-') { flags |= flag_reproc; break; } flags |= flag_num_negative; continue; } else { sprintf (error, "%d:%d: Unexpected %c when seeking value", line_and_col, b); goto e_failed; } }; }; } else { switch (top->type) { case json_object: switch (b) { whitespace: continue; case '"': if (flags & flag_need_comma) { sprintf (error, "%d:%d: Expected , before \"", line_and_col); goto e_failed; } flags |= flag_string; string = (json_char *) top->_reserved.object_mem; string_length = 0; break; case '}': flags = (flags & ~ flag_need_comma) | flag_next; break; case ',': if (flags & flag_need_comma) { flags &= ~ flag_need_comma; break; } default: sprintf (error, "%d:%d: Unexpected `%c` in object", line_and_col, b); goto e_failed; }; break; case json_integer: case json_double: if (isdigit (b)) { ++ num_digits; if (top->type == json_integer || flags & flag_num_e) { if (! (flags & flag_num_e)) { if (flags & flag_num_zero) { sprintf (error, "%d:%d: Unexpected `0` before `%c`", line_and_col, b); goto e_failed; } if (num_digits == 1 && b == '0') flags |= flag_num_zero; } else { flags |= flag_num_e_got_sign; num_e = (num_e * 10) + (b - '0'); continue; } top->u.integer = (top->u.integer * 10) + (b - '0'); continue; } num_fraction = (num_fraction * 10) + (b - '0'); continue; } if (b == '+' || b == '-') { if ( (flags & flag_num_e) && !(flags & flag_num_e_got_sign)) { flags |= flag_num_e_got_sign; if (b == '-') flags |= flag_num_e_negative; continue; } } else if (b == '.' && top->type == json_integer) { if (!num_digits) { sprintf (error, "%d:%d: Expected digit before `.`", line_and_col); goto e_failed; } top->type = json_double; #ifdef JSON_FLOATING_POINT top->u.dbl = (double) top->u.integer; #endif num_digits = 0; continue; } if (! (flags & flag_num_e)) { if (top->type == json_double) { if (!num_digits) { sprintf (error, "%d:%d: Expected digit after `.`", line_and_col); goto e_failed; } #ifdef JSON_FLOATING_POINT top->u.dbl += ((double) num_fraction) / (pow (10.0, (double) num_digits)); #endif } if (b == 'e' || b == 'E') { flags |= flag_num_e; if (top->type == json_integer) { top->type = json_double; #ifdef JSON_FLOATING_POINT top->u.dbl = (double) top->u.integer; #endif } num_digits = 0; flags &= ~ flag_num_zero; continue; } } else { if (!num_digits) { sprintf (error, "%d:%d: Expected digit after `e`", line_and_col); goto e_failed; } #ifdef JSON_FLOATING_POINT top->u.dbl *= pow (10.0, (double) (flags & flag_num_e_negative ? - num_e : num_e)); #endif } if (flags & flag_num_negative) { if (top->type == json_integer) top->u.integer = - top->u.integer; #ifdef JSON_FLOATING_POINT else top->u.dbl = - top->u.dbl; #endif } flags |= flag_next | flag_reproc; break; default: break; }; } if (flags & flag_reproc) { flags &= ~ flag_reproc; -- state.ptr; } if (flags & flag_next) { flags = (flags & ~ flag_next) | flag_need_comma; if (!top->parent) { /* root value done */ flags |= flag_done; continue; } if (top->parent->type == json_array) flags |= flag_seek_value; if (!state.first_pass) { json_value * parent = top->parent; switch (parent->type) { case json_object: parent->u.object.values [parent->u.object.length].value = top; break; case json_array: parent->u.array.values [parent->u.array.length] = top; break; default: break; }; } if ( (++ top->parent->u.array.length) > state.uint_max) goto e_overflow; top = top->parent; continue; } } alloc = root; } return root; e_unknown_value: sprintf (error, "%d:%d: Unknown value", line_and_col); goto e_failed; e_alloc_failure: strcpy (error, "Memory allocation failure"); goto e_failed; e_overflow: sprintf (error, "%d:%d: Too long (caught overflow)", line_and_col); goto e_failed; e_failed: if (error_buf) { if (*error) strcpy (error_buf, error); else strcpy (error_buf, "Unknown error"); } if (state.first_pass) alloc = root; while (alloc) { top = alloc->_reserved.next_alloc; state.settings.mem_free (alloc, state.settings.user_data); alloc = top; } if (!state.first_pass) json_value_free_ex (&state.settings, root); return 0; } json_value * json_parse (const json_char * json, size_t length) { json_settings settings = { 0 }; return json_parse_ex (&settings, json, length, 0); } void json_value_free_ex (json_settings * settings, json_value * value) { json_value * cur_value; if (!value) return; value->parent = 0; while (value) { switch (value->type) { case json_array: if (!value->u.array.length) { settings->mem_free (value->u.array.values, settings->user_data); break; } value = value->u.array.values [-- value->u.array.length]; continue; case json_object: if (!value->u.object.length) { settings->mem_free (value->u.object.values, settings->user_data); break; } value = value->u.object.values [-- value->u.object.length].value; continue; case json_string: settings->mem_free (value->u.string.ptr, settings->user_data); break; default: break; }; cur_value = value; value = value->parent; settings->mem_free (cur_value, settings->user_data); } } void json_value_free (json_value * value) { json_settings settings = { 0 }; settings.mem_free = default_free; json_value_free_ex (&settings, value); }