/* 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
const struct _json_value json_value_none;
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
typedef unsigned int json_uchar;
static unsigned char hex_value (json_uchar 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_uchar 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 = (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 = (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;
switch (b)
{
whitespace:
continue;
default:
sprintf (error, "%d:%d: Trailing garbage: `%c`",
state.cur_line, state.cur_col, b);
goto e_failed;
};
}
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;
top->u.dbl = (double) top->u.integer;
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;
}
top->u.dbl += ((double) num_fraction) / (pow (10.0, (double) num_digits));
}
if (b == 'e' || b == 'E')
{
flags |= flag_num_e;
if (top->type == json_integer)
{
top->type = json_double;
top->u.dbl = (double) top->u.integer;
}
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;
}
top->u.dbl *= pow (10.0, (double)
(flags & flag_num_e_negative ? - num_e : num_e));
}
if (flags & flag_num_negative)
{
if (top->type == json_integer)
top->u.integer = - top->u.integer;
else
top->u.dbl = - top->u.dbl;
}
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);
}