source: lib/json.h @ 73f0a01

/* 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
      #include <inttypes.h>
      #define json_int_t int64_t
   #else
      #define json_int_t __int64
   #endif
#endif

#include <stdlib.h>

#ifdef __cplusplus

   #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 */

} 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_value {
        struct _json_value * parent;

        json_type type;

        union {
                int boolean;
                json_int_t integer;
                double dbl;

                struct {
                        unsigned int length;
                        json_char * ptr; /* null terminated */

                } string;

                struct {
                        unsigned int length;

                        struct {
                                json_char * name;
                                unsigned int name_length;

                                struct _json_value * value;

                        } * 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;


        /* 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