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/*
* $Id: json_object.h,v 1.12 2006/01/30 23:07:57 mclark Exp $
*
* Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd.
* Michael Clark <michael@metaparadigm.com>
* Copyright (c) 2009 Hewlett-Packard Development Company, L.P.
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the MIT license. See COPYING for details.
*
*/
/**
* @file
* @brief Core json-c API. Start here, or with json_tokener.h
*/
#ifndef _json_object_h_
#define _json_object_h_
#ifdef __GNUC__
#define JSON_C_CONST_FUNCTION(func) func __attribute__((const))
#else
#define JSON_C_CONST_FUNCTION(func) func
#endif
#include "json_inttypes.h"
#include "json_types.h"
#include "printbuf.h"
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
#define JSON_OBJECT_DEF_HASH_ENTRIES 16
/**
* A flag for the json_object_to_json_string_ext() and
* json_object_to_file_ext() functions which causes the output
* to have no extra whitespace or formatting applied.
*/
#define JSON_C_TO_STRING_PLAIN 0
/**
* A flag for the json_object_to_json_string_ext() and
* json_object_to_file_ext() functions which causes the output to have
* minimal whitespace inserted to make things slightly more readable.
*/
#define JSON_C_TO_STRING_SPACED (1 << 0)
/**
* A flag for the json_object_to_json_string_ext() and
* json_object_to_file_ext() functions which causes
* the output to be formatted.
*
* See the "Two Space Tab" option at https://jsonformatter.curiousconcept.com/
* for an example of the format.
*/
#define JSON_C_TO_STRING_PRETTY (1 << 1)
/**
* A flag for the json_object_to_json_string_ext() and
* json_object_to_file_ext() functions which causes
* the output to be formatted.
*
* Instead of a "Two Space Tab" this gives a single tab character.
*/
#define JSON_C_TO_STRING_PRETTY_TAB (1 << 3)
/**
* A flag to drop trailing zero for float values
*/
#define JSON_C_TO_STRING_NOZERO (1 << 2)
/**
* Don't escape forward slashes.
*/
#define JSON_C_TO_STRING_NOSLASHESCAPE (1 << 4)
/**
* A flag for the json_object_to_json_string_ext() and
* json_object_to_file_ext() functions which causes
* the output to be formatted.
*
* Use color for printing json.
*/
#define JSON_C_TO_STRING_COLOR (1 << 5)
/**
* A flag for the json_object_object_add_ex function which
* causes the value to be added without a check if it already exists.
* Note: it is the responsibility of the caller to ensure that no
* key is added multiple times. If this is done, results are
* unpredictable. While this option is somewhat dangerous, it
* permits potentially large performance savings in code that
* knows for sure the key values are unique (e.g. because the
* code adds a well-known set of constant key values).
*/
#define JSON_C_OBJECT_ADD_KEY_IS_NEW (1 << 1)
/**
* A flag for the json_object_object_add_ex function which
* flags the key as being constant memory. This means that
* the key will NOT be copied via strdup(), resulting in a
* potentially huge performance win (malloc, strdup and
* free are usually performance hogs). It is acceptable to
* use this flag for keys in non-constant memory blocks if
* the caller ensure that the memory holding the key lives
* longer than the corresponding json object. However, this
* is somewhat dangerous and should only be done if really
* justified.
* The general use-case for this flag is cases where the
* key is given as a real constant value in the function
* call, e.g. as in
* json_object_object_add_ex(obj, "ip", json,
* JSON_C_OBJECT_ADD_CONSTANT_KEY);
*/
#define JSON_C_OBJECT_ADD_CONSTANT_KEY (1 << 2)
/**
* This flag is an alias to JSON_C_OBJECT_ADD_CONSTANT_KEY.
* Historically, this flag was used first and the new name
* JSON_C_OBJECT_ADD_CONSTANT_KEY was introduced for version
* 0.16.00 in order to have regular naming.
* Use of this flag is now legacy.
*/
#define JSON_C_OBJECT_KEY_IS_CONSTANT JSON_C_OBJECT_ADD_CONSTANT_KEY
/**
* Set the global value of an option, which will apply to all
* current and future threads that have not set a thread-local value.
*
* @see json_c_set_serialization_double_format
*/
#define JSON_C_OPTION_GLOBAL (0)
/**
* Set a thread-local value of an option, overriding the global value.
* This will fail if json-c is not compiled with threading enabled, and
* with the __thread specifier (or equivalent) available.
*
* @see json_c_set_serialization_double_format
*/
#define JSON_C_OPTION_THREAD (1)
/* reference counting functions */
/**
* Increment the reference count of json_object, thereby taking ownership of it.
*
* Cases where you might need to increase the refcount include:
* - Using an object field or array index (retrieved through
* `json_object_object_get()` or `json_object_array_get_idx()`)
* beyond the lifetime of the parent object.
* - Detaching an object field or array index from its parent object
* (using `json_object_object_del()` or `json_object_array_del_idx()`)
* - Sharing a json_object with multiple (not necessarily parallel) threads
* of execution that all expect to free it (with `json_object_put()`) when
* they're done.
*
* @param obj the json_object instance
* @see json_object_put()
* @see json_object_object_get()
* @see json_object_array_get_idx()
*/
JSON_EXPORT struct json_object *json_object_get(struct json_object *obj);
/**
* Decrement the reference count of json_object and free if it reaches zero.
*
* You must have ownership of obj prior to doing this or you will cause an
* imbalance in the reference count, leading to a classic use-after-free bug.
* In particular, you normally do not need to call `json_object_put()` on the
* json_object returned by `json_object_object_get()` or `json_object_array_get_idx()`.
*
* Just like after calling `free()` on a block of memory, you must not use
* `obj` after calling `json_object_put()` on it or any object that it
* is a member of (unless you know you've called `json_object_get(obj)` to
* explicitly increment the refcount).
*
* NULL may be passed, which which case this is a no-op.
*
* @param obj the json_object instance
* @returns 1 if the object was freed.
* @see json_object_get()
*/
JSON_EXPORT int json_object_put(struct json_object *obj);
/**
* Check if the json_object is of a given type
* @param obj the json_object instance
* @param type one of:
json_type_null (i.e. obj == NULL),
json_type_boolean,
json_type_double,
json_type_int,
json_type_object,
json_type_array,
json_type_string
*/
JSON_EXPORT int json_object_is_type(const struct json_object *obj, enum json_type type);
/**
* Get the type of the json_object. See also json_type_to_name() to turn this
* into a string suitable, for instance, for logging.
*
* @param obj the json_object instance
* @returns type being one of:
json_type_null (i.e. obj == NULL),
json_type_boolean,
json_type_double,
json_type_int,
json_type_object,
json_type_array,
json_type_string
*/
JSON_EXPORT enum json_type json_object_get_type(const struct json_object *obj);
/** Stringify object to json format.
* Equivalent to json_object_to_json_string_ext(obj, JSON_C_TO_STRING_SPACED)
* The pointer you get is an internal of your json object. You don't
* have to free it, later use of json_object_put() should be sufficient.
* If you can not ensure there's no concurrent access to *obj use
* strdup().
* @param obj the json_object instance
* @returns a string in JSON format
*/
JSON_EXPORT const char *json_object_to_json_string(struct json_object *obj);
/** Stringify object to json format
* @see json_object_to_json_string() for details on how to free string.
* @param obj the json_object instance
* @param flags formatting options, see JSON_C_TO_STRING_PRETTY and other constants
* @returns a string in JSON format
*/
JSON_EXPORT const char *json_object_to_json_string_ext(struct json_object *obj, int flags);
/** Stringify object to json format
* @see json_object_to_json_string() for details on how to free string.
* @param obj the json_object instance
* @param flags formatting options, see JSON_C_TO_STRING_PRETTY and other constants
* @param length a pointer where, if not NULL, the length (without null) is stored
* @returns a string in JSON format and the length if not NULL
*/
JSON_EXPORT const char *json_object_to_json_string_length(struct json_object *obj, int flags,
size_t *length);
/**
* Returns the userdata set by json_object_set_userdata() or
* json_object_set_serializer()
*
* @param jso the object to return the userdata for
*/
JSON_EXPORT void *json_object_get_userdata(json_object *jso);
/**
* Set an opaque userdata value for an object
*
* The userdata can be retrieved using json_object_get_userdata().
*
* If custom userdata is already set on this object, any existing user_delete
* function is called before the new one is set.
*
* The user_delete parameter is optional and may be passed as NULL, even if
* the userdata parameter is non-NULL. It will be called just before the
* json_object is deleted, after it's reference count goes to zero
* (see json_object_put()).
* If this is not provided, it is up to the caller to free the userdata at
* an appropriate time. (i.e. after the json_object is deleted)
*
* Note: Objects created by parsing strings may have custom serializers set
* which expect the userdata to contain specific data (due to use of
* json_object_new_double_s()). In this case, json_object_set_serialiser() with
* NULL as to_string_func should be used instead to set the userdata and reset
* the serializer to its default value.
*
* @param jso the object to set the userdata for
* @param userdata an optional opaque cookie
* @param user_delete an optional function from freeing userdata
*/
JSON_EXPORT void json_object_set_userdata(json_object *jso, void *userdata,
json_object_delete_fn *user_delete);
/**
* Set a custom serialization function to be used when this particular object
* is converted to a string by json_object_to_json_string.
*
* If custom userdata is already set on this object, any existing user_delete
* function is called before the new one is set.
*
* If to_string_func is NULL the default behaviour is reset (but the userdata
* and user_delete fields are still set).
*
* The userdata parameter is optional and may be passed as NULL. It can be used
* to provide additional data for to_string_func to use. This parameter may
* be NULL even if user_delete is non-NULL.
*
* The user_delete parameter is optional and may be passed as NULL, even if
* the userdata parameter is non-NULL. It will be called just before the
* json_object is deleted, after it's reference count goes to zero
* (see json_object_put()).
* If this is not provided, it is up to the caller to free the userdata at
* an appropriate time. (i.e. after the json_object is deleted)
*
* Note that the userdata is the same as set by json_object_set_userdata(), so
* care must be taken not to overwrite the value when both a custom serializer
* and json_object_set_userdata() are used.
*
* @param jso the object to customize
* @param to_string_func the custom serialization function
* @param userdata an optional opaque cookie
* @param user_delete an optional function from freeing userdata
*/
JSON_EXPORT void json_object_set_serializer(json_object *jso,
json_object_to_json_string_fn *to_string_func,
void *userdata, json_object_delete_fn *user_delete);
#ifdef __clang__
/*
* Clang doesn't pay attention to the parameters defined in the
* function typedefs used here, so turn off spurious doc warnings.
* {
*/
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdocumentation"
#endif
/**
* Simply call free on the userdata pointer.
* Can be used with json_object_set_serializer().
*
* @param jso unused
* @param userdata the pointer that is passed to free().
*/
JSON_EXPORT json_object_delete_fn json_object_free_userdata;
/**
* Copy the jso->_userdata string over to pb as-is.
* Can be used with json_object_set_serializer().
*
* @param jso The object whose _userdata is used.
* @param pb The destination buffer.
* @param level Ignored.
* @param flags Ignored.
*/
JSON_EXPORT json_object_to_json_string_fn json_object_userdata_to_json_string;
#ifdef __clang__
/* } */
#pragma clang diagnostic pop
#endif
/* object type methods */
/** Create a new empty object with a reference count of 1. The caller of
* this object initially has sole ownership. Remember, when using
* json_object_object_add or json_object_array_put_idx, ownership will
* transfer to the object/array. Call json_object_get if you want to maintain
* shared ownership or also add this object as a child of multiple objects or
* arrays. Any ownerships you acquired but did not transfer must be released
* through json_object_put.
*
* @returns a json_object of type json_type_object
*/
JSON_EXPORT struct json_object *json_object_new_object(void);
/** Get the hashtable of a json_object of type json_type_object
* @param obj the json_object instance
* @returns a linkhash
*/
JSON_EXPORT struct lh_table *json_object_get_object(const struct json_object *obj);
/** Get the size of an object in terms of the number of fields it has.
* @param obj the json_object whose length to return
*/
JSON_EXPORT int json_object_object_length(const struct json_object *obj);
/** Get the sizeof (struct json_object).
* @returns a size_t with the sizeof (struct json_object)
*/
JSON_C_CONST_FUNCTION(JSON_EXPORT size_t json_c_object_sizeof(void));
/** Add an object field to a json_object of type json_type_object
*
* The reference count of `val` will *not* be incremented, in effect
* transferring ownership that object to `obj`, and thus `val` will be
* freed when `obj` is. (i.e. through `json_object_put(obj)`)
*
* If you want to retain a reference to the added object, independent
* of the lifetime of obj, you must increment the refcount with
* `json_object_get(val)` (and later release it with json_object_put()).
*
* Since ownership transfers to `obj`, you must make sure
* that you do in fact have ownership over `val`. For instance,
* json_object_new_object() will give you ownership until you transfer it,
* whereas json_object_object_get() does not.
*
* Any previous object stored under `key` in `obj` will have its refcount
* decremented, and be freed normally if that drops to zero.
*
* @param obj the json_object instance
* @param key the object field name (a private copy will be duplicated)
* @param val a json_object or NULL member to associate with the given field
*
* @return On success, <code>0</code> is returned.
* On error, a negative value is returned.
*/
JSON_EXPORT int json_object_object_add(struct json_object *obj, const char *key,
struct json_object *val);
/** Add an object field to a json_object of type json_type_object
*
* The semantics are identical to json_object_object_add, except that an
* additional flag fields gives you more control over some detail aspects
* of processing. See the description of JSON_C_OBJECT_ADD_* flags for more
* details.
*
* @param obj the json_object instance
* @param key the object field name (a private copy will be duplicated)
* @param val a json_object or NULL member to associate with the given field
* @param opts process-modifying options. To specify multiple options, use
* (OPT1|OPT2)
*/
JSON_EXPORT int json_object_object_add_ex(struct json_object *obj, const char *const key,
struct json_object *const val, const unsigned opts);
/** Get the json_object associate with a given object field.
* Deprecated/discouraged: used json_object_object_get_ex instead.
*
* This returns NULL if the field is found but its value is null, or if
* the field is not found, or if obj is not a json_type_object. If you
* need to distinguish between these cases, use json_object_object_get_ex().
*
* *No* reference counts will be changed. There is no need to manually adjust
* reference counts through the json_object_put/json_object_get methods unless
* you need to have the child (value) reference maintain a different lifetime
* than the owning parent (obj). Ownership of the returned value is retained
* by obj (do not do json_object_put unless you have done a json_object_get).
* If you delete the value from obj (json_object_object_del) and wish to access
* the returned reference afterwards, make sure you have first gotten shared
* ownership through json_object_get (& don't forget to do a json_object_put
* or transfer ownership to prevent a memory leak).
*
* @param obj the json_object instance
* @param key the object field name
* @returns the json_object associated with the given field name
*/
JSON_EXPORT struct json_object *json_object_object_get(const struct json_object *obj,
const char *key);
/** Get the json_object associated with a given object field.
*
* This returns true if the key is found, false in all other cases (including
* if obj isn't a json_type_object).
*
* *No* reference counts will be changed. There is no need to manually adjust
* reference counts through the json_object_put/json_object_get methods unless
* you need to have the child (value) reference maintain a different lifetime
* than the owning parent (obj). Ownership of value is retained by obj.
*
* @param obj the json_object instance
* @param key the object field name
* @param value a pointer where to store a reference to the json_object
* associated with the given field name.
*
* It is safe to pass a NULL value.
* @returns whether or not the key exists
*/
JSON_EXPORT json_bool json_object_object_get_ex(const struct json_object *obj, const char *key,
struct json_object **value);
/** Delete the given json_object field
*
* The reference count will be decremented for the deleted object. If there
* are no more owners of the value represented by this key, then the value is
* freed. Otherwise, the reference to the value will remain in memory.
*
* @param obj the json_object instance
* @param key the object field name
*/
JSON_EXPORT void json_object_object_del(struct json_object *obj, const char *key);
/**
* Iterate through all keys and values of an object.
*
* Adding keys to the object while iterating is NOT allowed.
*
* Deleting an existing key, or replacing an existing key with a
* new value IS allowed.
*
* @param obj the json_object instance
* @param key the local name for the char* key variable defined in the body
* @param val the local name for the json_object* object variable defined in
* the body
*/
#if defined(__GNUC__) && !defined(__STRICT_ANSI__) && (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L)
#define json_object_object_foreach(obj, key, val) \
char *key = NULL; \
struct json_object *val __attribute__((__unused__)) = NULL; \
for (struct lh_entry *entry##key = lh_table_head(json_object_get_object(obj)), \
*entry_next##key = NULL; \
({ \
if (entry##key) \
{ \
key = (char *)lh_entry_k(entry##key); \
val = (struct json_object *)lh_entry_v(entry##key); \
entry_next##key = lh_entry_next(entry##key); \
}; \
entry##key; \
}); \
entry##key = entry_next##key)
#else /* ANSI C or MSC */
#define json_object_object_foreach(obj, key, val) \
char *key = NULL; \
struct json_object *val = NULL; \
struct lh_entry *entry##key; \
struct lh_entry *entry_next##key = NULL; \
for (entry##key = lh_table_head(json_object_get_object(obj)); \
(entry##key ? (key = (char *)lh_entry_k(entry##key), \
val = (struct json_object *)lh_entry_v(entry##key), \
entry_next##key = lh_entry_next(entry##key), entry##key) \
: 0); \
entry##key = entry_next##key)
#endif /* defined(__GNUC__) && !defined(__STRICT_ANSI__) && (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) */
/** Iterate through all keys and values of an object (ANSI C Safe)
* @param obj the json_object instance
* @param iter the object iterator, use type json_object_iter
*/
#define json_object_object_foreachC(obj, iter) \
for (iter.entry = lh_table_head(json_object_get_object(obj)); \
(iter.entry ? (iter.key = (char *)lh_entry_k(iter.entry), \
iter.val = (struct json_object *)lh_entry_v(iter.entry), iter.entry) \
: 0); \
iter.entry = lh_entry_next(iter.entry))
/* Array type methods */
/** Create a new empty json_object of type json_type_array
* with 32 slots allocated.
* If you know the array size you'll need ahead of time, use
* json_object_new_array_ext() instead.
* @see json_object_new_array_ext()
* @see json_object_array_shrink()
* @returns a json_object of type json_type_array
*/
JSON_EXPORT struct json_object *json_object_new_array(void);
/** Create a new empty json_object of type json_type_array
* with the desired number of slots allocated.
* @see json_object_array_shrink()
* @param initial_size the number of slots to allocate
* @returns a json_object of type json_type_array
*/
JSON_EXPORT struct json_object *json_object_new_array_ext(int initial_size);
/** Get the arraylist of a json_object of type json_type_array
* @param obj the json_object instance
* @returns an arraylist
*/
JSON_EXPORT struct array_list *json_object_get_array(const struct json_object *obj);
/** Get the length of a json_object of type json_type_array
* @param obj the json_object instance
* @returns an int
*/
JSON_EXPORT size_t json_object_array_length(const struct json_object *obj);
/** Sorts the elements of jso of type json_type_array
*
* Pointers to the json_object pointers will be passed as the two arguments
* to sort_fn
*
* @param jso the json_object instance
* @param sort_fn a sorting function
*/
JSON_EXPORT void json_object_array_sort(struct json_object *jso,
int (*sort_fn)(const void *, const void *));
/** Binary search a sorted array for a specified key object.
*
* It depends on your compare function what's sufficient as a key.
* Usually you create some dummy object with the parameter compared in
* it, to identify the right item you're actually looking for.
*
* @see json_object_array_sort() for hints on the compare function.
*
* @param key a dummy json_object with the right key
* @param jso the array object we're searching
* @param sort_fn the sort/compare function
*
* @return the wanted json_object instance
*/
JSON_EXPORT struct json_object *
json_object_array_bsearch(const struct json_object *key, const struct json_object *jso,
int (*sort_fn)(const void *, const void *));
/** Add an element to the end of a json_object of type json_type_array
*
* The reference count will *not* be incremented. This is to make adding
* fields to objects in code more compact. If you want to retain a reference
* to an added object you must wrap the passed object with json_object_get
*
* @param obj the json_object instance
* @param val the json_object to be added
*/
JSON_EXPORT int json_object_array_add(struct json_object *obj, struct json_object *val);
/** Insert or replace an element at a specified index in an array (a json_object of type json_type_array)
*
* The reference count will *not* be incremented. This is to make adding
* fields to objects in code more compact. If you want to retain a reference
* to an added object you must wrap the passed object with json_object_get
*
* The reference count of a replaced object will be decremented.
*
* The array size will be automatically be expanded to the size of the
* index if the index is larger than the current size.
*
* @param obj the json_object instance
* @param idx the index to insert the element at
* @param val the json_object to be added
*/
JSON_EXPORT int json_object_array_put_idx(struct json_object *obj, size_t idx,
struct json_object *val);
/** Insert an element at a specified index in an array (a json_object of type json_type_array)
*
* The reference count will *not* be incremented. This is to make adding
* fields to objects in code more compact. If you want to retain a reference
* to an added object you must wrap the passed object with json_object_get
*
* The array size will be automatically be expanded to the size of the
* index if the index is larger than the current size.
* If the index is within the existing array limits, then the element will be
* inserted and all elements will be shifted. This is the only difference between
* this function and json_object_array_put_idx().
*
* @param obj the json_object instance
* @param idx the index to insert the element at
* @param val the json_object to be added
*/
JSON_EXPORT int json_object_array_insert_idx(struct json_object *obj, size_t idx,
struct json_object *val);
/** Get the element at specified index of array `obj` (which must be a json_object of type json_type_array)
*
* *No* reference counts will be changed, and ownership of the returned
* object remains with `obj`. See json_object_object_get() for additional
* implications of this behavior.
*
* Calling this with anything other than a json_type_array will trigger
* an assert.
*
* @param obj the json_object instance
* @param idx the index to get the element at
* @returns the json_object at the specified index (or NULL)
*/
JSON_EXPORT struct json_object *json_object_array_get_idx(const struct json_object *obj,
size_t idx);
/** Delete an elements from a specified index in an array (a json_object of type json_type_array)
*
* The reference count will be decremented for each of the deleted objects. If there
* are no more owners of an element that is being deleted, then the value is
* freed. Otherwise, the reference to the value will remain in memory.
*
* @param obj the json_object instance
* @param idx the index to start deleting elements at
* @param count the number of elements to delete
* @returns 0 if the elements were successfully deleted
*/
JSON_EXPORT int json_object_array_del_idx(struct json_object *obj, size_t idx, size_t count);
/**
* Shrink the internal memory allocation of the array to just
* enough to fit the number of elements in it, plus empty_slots.
*
* @param jso the json_object instance, must be json_type_array
* @param empty_slots the number of empty slots to leave allocated
*/
JSON_EXPORT int json_object_array_shrink(struct json_object *jso, int empty_slots);
/* json_bool type methods */
/** Create a new empty json_object of type json_type_boolean
* @param b a json_bool 1 or 0
* @returns a json_object of type json_type_boolean
*/
JSON_EXPORT struct json_object *json_object_new_boolean(json_bool b);
/** Get the json_bool value of a json_object
*
* The type is coerced to a json_bool if the passed object is not a json_bool.
* integer and double objects will return 0 if there value is zero
* or 1 otherwise. If the passed object is a string it will return
* 1 if it has a non zero length.
* If any other object type is passed 0 will be returned, even non-empty
* json_type_array and json_type_object objects.
*
* @param obj the json_object instance
* @returns a json_bool
*/
JSON_EXPORT json_bool json_object_get_boolean(const struct json_object *obj);
/** Set the json_bool value of a json_object
*
* The type of obj is checked to be a json_type_boolean and 0 is returned
* if it is not without any further actions. If type of obj is json_type_boolean
* the object value is changed to new_value
*
* @param obj the json_object instance
* @param new_value the value to be set
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_boolean(struct json_object *obj, json_bool new_value);
/* int type methods */
/** Create a new empty json_object of type json_type_int
* Note that values are stored as 64-bit values internally.
* To ensure the full range is maintained, use json_object_new_int64 instead.
* @param i the integer
* @returns a json_object of type json_type_int
*/
JSON_EXPORT struct json_object *json_object_new_int(int32_t i);
/** Create a new empty json_object of type json_type_int
* @param i the integer
* @returns a json_object of type json_type_int
*/
JSON_EXPORT struct json_object *json_object_new_int64(int64_t i);
/** Create a new empty json_object of type json_type_uint
* @param i the integer
* @returns a json_object of type json_type_uint
*/
JSON_EXPORT struct json_object *json_object_new_uint64(uint64_t i);
/** Get the int value of a json_object
*
* The type is coerced to a int if the passed object is not a int.
* double objects will return their integer conversion. Strings will be
* parsed as an integer. If no conversion exists then 0 is returned
* and errno is set to EINVAL. null is equivalent to 0 (no error values set)
*
* Note that integers are stored internally as 64-bit values.
* If the value of too big or too small to fit into 32-bit, INT32_MAX or
* INT32_MIN are returned, respectively.
*
* @param obj the json_object instance
* @returns an int
*/
JSON_EXPORT int32_t json_object_get_int(const struct json_object *obj);
/** Set the int value of a json_object
*
* The type of obj is checked to be a json_type_int and 0 is returned
* if it is not without any further actions. If type of obj is json_type_int
* the object value is changed to new_value
*
* @param obj the json_object instance
* @param new_value the value to be set
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_int(struct json_object *obj, int new_value);
/** Increment a json_type_int object by the given amount, which may be negative.
*
* If the type of obj is not json_type_int then 0 is returned with no further
* action taken.
* If the addition would result in a overflow, the object value
* is set to INT64_MAX.
* If the addition would result in a underflow, the object value
* is set to INT64_MIN.
* Neither overflow nor underflow affect the return value.
*
* @param obj the json_object instance
* @param val the value to add
* @returns 1 if the increment succeeded, 0 otherwise
*/
JSON_EXPORT int json_object_int_inc(struct json_object *obj, int64_t val);
/** Get the int value of a json_object
*
* The type is coerced to a int64 if the passed object is not a int64.
* double objects will return their int64 conversion. Strings will be
* parsed as an int64. If no conversion exists then 0 is returned.
*
* NOTE: Set errno to 0 directly before a call to this function to determine
* whether or not conversion was successful (it does not clear the value for
* you).
*
* @param obj the json_object instance
* @returns an int64
*/
JSON_EXPORT int64_t json_object_get_int64(const struct json_object *obj);
/** Get the uint value of a json_object
*
* The type is coerced to a uint64 if the passed object is not a uint64.
* double objects will return their uint64 conversion. Strings will be
* parsed as an uint64. If no conversion exists then 0 is returned.
*
* NOTE: Set errno to 0 directly before a call to this function to determine
* whether or not conversion was successful (it does not clear the value for
* you).
*
* @param obj the json_object instance
* @returns an uint64
*/
JSON_EXPORT uint64_t json_object_get_uint64(const struct json_object *obj);
/** Set the int64_t value of a json_object
*
* The type of obj is checked to be a json_type_int and 0 is returned
* if it is not without any further actions. If type of obj is json_type_int
* the object value is changed to new_value
*
* @param obj the json_object instance
* @param new_value the value to be set
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_int64(struct json_object *obj, int64_t new_value);
/** Set the uint64_t value of a json_object
*
* The type of obj is checked to be a json_type_uint and 0 is returned
* if it is not without any further actions. If type of obj is json_type_uint
* the object value is changed to new_value
*
* @param obj the json_object instance
* @param new_value the value to be set
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_uint64(struct json_object *obj, uint64_t new_value);
/* double type methods */
/** Create a new empty json_object of type json_type_double
*
* @see json_object_double_to_json_string() for how to set a custom format string.
*
* @param d the double
* @returns a json_object of type json_type_double
*/
JSON_EXPORT struct json_object *json_object_new_double(double d);
/**
* Create a new json_object of type json_type_double, using
* the exact serialized representation of the value.
*
* This allows for numbers that would otherwise get displayed
* inefficiently (e.g. 12.3 => "12.300000000000001") to be
* serialized with the more convenient form.
*
* Notes:
*
* This is used by json_tokener_parse_ex() to allow for
* an exact re-serialization of a parsed object.
*
* The userdata field is used to store the string representation, so it
* can't be used for other data if this function is used.
*
* A roughly equivalent sequence of calls, with the difference being that
* the serialization function won't be reset by json_object_set_double(), is:
* @code
* jso = json_object_new_double(d);
* json_object_set_serializer(jso, json_object_userdata_to_json_string,
* strdup(ds), json_object_free_userdata);
* @endcode
*
* @param d the numeric value of the double.
* @param ds the string representation of the double. This will be copied.
*/
JSON_EXPORT struct json_object *json_object_new_double_s(double d, const char *ds);
/**
* Set a global or thread-local json-c option, depending on whether
* JSON_C_OPTION_GLOBAL or JSON_C_OPTION_THREAD is passed.
* Thread-local options default to undefined, and inherit from the global
* value, even if the global value is changed after the thread is created.
* Attempting to set thread-local options when threading is not compiled in
* will result in an error. Be sure to check the return value.
*
* double_format is a "%g" printf format, such as "%.20g"
*
* @return -1 on errors, 0 on success.
*/
JSON_EXPORT int json_c_set_serialization_double_format(const char *double_format,
int global_or_thread);
/** Serialize a json_object of type json_type_double to a string.
*
* This function isn't meant to be called directly. Instead, you can set a
* custom format string for the serialization of this double using the
* following call (where "%.17g" actually is the default):
*
* @code
* jso = json_object_new_double(d);
* json_object_set_serializer(jso, json_object_double_to_json_string,
* "%.17g", NULL);
* @endcode
*
* @see printf(3) man page for format strings
*
* @param jso The json_type_double object that is serialized.
* @param pb The destination buffer.
* @param level Ignored.
* @param flags Ignored.
*/
JSON_EXPORT int json_object_double_to_json_string(struct json_object *jso, struct printbuf *pb,
int level, int flags);
/** Get the double floating point value of a json_object
*
* The type is coerced to a double if the passed object is not a double.
* integer objects will return their double conversion. Strings will be
* parsed as a double. If no conversion exists then 0.0 is returned and
* errno is set to EINVAL. null is equivalent to 0 (no error values set)
*
* If the value is too big to fit in a double, then the value is set to
* the closest infinity with errno set to ERANGE. If strings cannot be
* converted to their double value, then EINVAL is set & NaN is returned.
*
* Arrays of length 0 are interpreted as 0 (with no error flags set).
* Arrays of length 1 are effectively cast to the equivalent object and
* converted using the above rules. All other arrays set the error to
* EINVAL & return NaN.
*
* NOTE: Set errno to 0 directly before a call to this function to
* determine whether or not conversion was successful (it does not clear
* the value for you).
*
* @param obj the json_object instance
* @returns a double floating point number
*/
JSON_EXPORT double json_object_get_double(const struct json_object *obj);
/** Set the double value of a json_object
*
* The type of obj is checked to be a json_type_double and 0 is returned
* if it is not without any further actions. If type of obj is json_type_double
* the object value is changed to new_value
*
* If the object was created with json_object_new_double_s(), the serialization
* function is reset to the default and the cached serialized value is cleared.
*
* @param obj the json_object instance
* @param new_value the value to be set
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_double(struct json_object *obj, double new_value);
/* string type methods */
/** Create a new empty json_object of type json_type_string
*
* A copy of the string is made and the memory is managed by the json_object
*
* @param s the string
* @returns a json_object of type json_type_string
* @see json_object_new_string_len()
*/
JSON_EXPORT struct json_object *json_object_new_string(const char *s);
/** Create a new empty json_object of type json_type_string and allocate
* len characters for the new string.
*
* A copy of the string is made and the memory is managed by the json_object
*
* @param s the string
* @param len max length of the new string
* @returns a json_object of type json_type_string
* @see json_object_new_string()
*/
JSON_EXPORT struct json_object *json_object_new_string_len(const char *s, const int len);
/** Get the string value of a json_object
*
* If the passed object is of type json_type_null (i.e. obj == NULL),
* NULL is returned.
*
* If the passed object of type json_type_string, the string contents
* are returned.
*
* Otherwise the JSON representation of the object is returned.
*
* The returned string memory is managed by the json_object and will
* be freed when the reference count of the json_object drops to zero.
*
* @param obj the json_object instance
* @returns a string or NULL
*/
JSON_EXPORT const char *json_object_get_string(struct json_object *obj);
/** Get the string length of a json_object
*
* If the passed object is not of type json_type_string then zero
* will be returned.
*
* @param obj the json_object instance
* @returns int
*/
JSON_EXPORT int json_object_get_string_len(const struct json_object *obj);
/** Set the string value of a json_object with zero terminated strings
* equivalent to json_object_set_string_len (obj, new_value, strlen(new_value))
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_string(json_object *obj, const char *new_value);
/** Set the string value of a json_object str
*
* The type of obj is checked to be a json_type_string and 0 is returned
* if it is not without any further actions. If type of obj is json_type_string
* the object value is changed to new_value
*
* @param obj the json_object instance
* @param new_value the value to be set; Since string length is given in len this need not be zero terminated
* @param len the length of new_value
* @returns 1 if value is set correctly, 0 otherwise
*/
JSON_EXPORT int json_object_set_string_len(json_object *obj, const char *new_value, int len);
/** This method exists only to provide a complementary function
* along the lines of the other json_object_new_* functions.
* It always returns NULL, and it is entirely acceptable to simply use NULL directly.
*/
JSON_EXPORT struct json_object *json_object_new_null(void);
/** Check if two json_object's are equal
*
* If the passed objects are equal 1 will be returned.
* Equality is defined as follows:
* - json_objects of different types are never equal
* - json_objects of the same primitive type are equal if the
* c-representation of their value is equal
* - json-arrays are considered equal if all values at the same
* indices are equal (same order)
* - Complex json_objects are considered equal if all
* contained objects referenced by their key are equal,
* regardless their order.
*
* @param obj1 the first json_object instance
* @param obj2 the second json_object instance
* @returns whether both objects are equal or not
*/
JSON_EXPORT int json_object_equal(struct json_object *obj1, struct json_object *obj2);
/**
* Perform a shallow copy of src into *dst as part of an overall json_object_deep_copy().
*
* If src is part of a containing object or array, parent will be non-NULL,
* and key or index will be provided.
* When shallow_copy is called *dst will be NULL, and must be non-NULL when it returns.
* src will never be NULL.
*
* If shallow_copy sets the serializer on an object, return 2 to indicate to
* json_object_deep_copy that it should not attempt to use the standard userdata
* copy function.
*
* @return On success 1 or 2, -1 on errors
*/
typedef int(json_c_shallow_copy_fn)(json_object *src, json_object *parent, const char *key,
size_t index, json_object **dst);
/**
* The default shallow copy implementation for use with json_object_deep_copy().
* This simply calls the appropriate json_object_new_<type>() function and
* copies over the serializer function (_to_json_string internal field of
* the json_object structure) but not any _userdata or _user_delete values.
*
* If you're writing a custom shallow_copy function, perhaps because you're using
* your own custom serializer, you can call this first to create the new object
* before customizing it with json_object_set_serializer().
*
* @return 1 on success, -1 on errors, but never 2.
*/
JSON_EXPORT json_c_shallow_copy_fn json_c_shallow_copy_default;
/**
* Copy the contents of the JSON object.
* The destination object must be initialized to NULL,
* to make sure this function won't overwrite an existing JSON object.
*
* This does roughly the same thing as
* `json_tokener_parse(json_object_get_string(src))`.
*
* @param src source JSON object whose contents will be copied
* @param dst pointer to the destination object where the contents of `src`;
* make sure this pointer is initialized to NULL
* @param shallow_copy an optional function to copy individual objects, needed
* when custom serializers are in use. See also
* json_object set_serializer.
*
* @returns 0 if the copy went well, -1 if an error occurred during copy
* or if the destination pointer is non-NULL
*/
JSON_EXPORT int json_object_deep_copy(struct json_object *src, struct json_object **dst,
json_c_shallow_copy_fn *shallow_copy);
#ifdef __cplusplus
}
#endif
#endif