DiskBrowser/json.h
Stephen Heumann 20345b436d JSON parsing code.
This is code from https://github.com/udp/json-parser (by James McLaughlin et al.), with some small modifications.
2019-04-10 15:29:15 -05:00

293 lines
6.5 KiB
C

/* 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.
*/
#ifndef _JSON_H
#define _JSON_H
#ifndef json_char
#define json_char char
#endif
#ifndef json_int_t
#ifndef _MSC_VER
#if __STDC_VERSION__ >= 199901L
#include <inttypes.h>
#define json_int_t int64_t
#else
#define json_int_t long
#endif
#else
#define json_int_t __int64
#endif
#endif
#include <stdlib.h>
#ifdef __cplusplus
#ifndef JSON_FLOATING_POINT
#define JSON_FLOATING_POINT
#endif
#include <string.h>
extern "C"
{
#endif
typedef struct
{
unsigned long max_memory;
int settings;
/* Custom allocator support (leave null to use malloc/free)
*/
void * (* mem_alloc) (size_t, int zero, void * user_data);
void (* mem_free) (void *, void * user_data);
void * user_data; /* will be passed to mem_alloc and mem_free */
size_t value_extra; /* how much extra space to allocate for values? */
} json_settings;
#define json_enable_comments 0x01
typedef enum
{
json_none,
json_object,
json_array,
json_integer,
json_double,
json_string,
json_boolean,
json_null
} json_type;
extern const struct _json_value json_value_none;
typedef struct _json_object_entry
{
json_char * name;
unsigned int name_length;
struct _json_value * value;
} json_object_entry;
typedef struct _json_value
{
struct _json_value * parent;
json_type type;
union
{
int boolean;
json_int_t integer;
#ifdef JSON_FLOATING_POINT
double dbl;
#endif
struct
{
unsigned int length;
json_char * ptr; /* null terminated */
} string;
struct
{
unsigned int length;
json_object_entry * values;
#if defined(__cplusplus) && __cplusplus >= 201103L
decltype(values) begin () const
{ return values;
}
decltype(values) end () const
{ return values + length;
}
#endif
} object;
struct
{
unsigned int length;
struct _json_value ** values;
#if defined(__cplusplus) && __cplusplus >= 201103L
decltype(values) begin () const
{ return values;
}
decltype(values) end () const
{ return values + length;
}
#endif
} array;
} u;
union
{
struct _json_value * next_alloc;
void * object_mem;
} _reserved;
#ifdef JSON_TRACK_SOURCE
/* Location of the value in the source JSON
*/
unsigned int line, col;
#endif
/* Some C++ operator sugar */
#ifdef __cplusplus
public:
inline _json_value ()
{ memset (this, 0, sizeof (_json_value));
}
inline const struct _json_value &operator [] (int index) const
{
if (type != json_array || index < 0
|| ((unsigned int) index) >= u.array.length)
{
return json_value_none;
}
return *u.array.values [index];
}
inline const struct _json_value &operator [] (const char * index) const
{
if (type != json_object)
return json_value_none;
for (unsigned int i = 0; i < u.object.length; ++ i)
if (!strcmp (u.object.values [i].name, index))
return *u.object.values [i].value;
return json_value_none;
}
inline operator const char * () const
{
switch (type)
{
case json_string:
return u.string.ptr;
default:
return "";
};
}
inline operator json_int_t () const
{
switch (type)
{
case json_integer:
return u.integer;
case json_double:
return (json_int_t) u.dbl;
default:
return 0;
};
}
inline operator bool () const
{
if (type != json_boolean)
return false;
return u.boolean != 0;
}
inline operator double () const
{
switch (type)
{
case json_integer:
return (double) u.integer;
case json_double:
return u.dbl;
default:
return 0;
};
}
#endif
} json_value;
json_value * json_parse (const json_char * json,
size_t length);
#define json_error_max 128
json_value * json_parse_ex (json_settings * settings,
const json_char * json,
size_t length,
char * error);
void json_value_free (json_value *);
/* Not usually necessary, unless you used a custom mem_alloc and now want to
* use a custom mem_free.
*/
void json_value_free_ex (json_settings * settings,
json_value *);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif