jstore

jstore#

Simple JSON storage.

This library maintains a simple JSON storage, whos root is a JSON object. The keys identify storage items and the values are valid JSON string representing the item values.

Items can be added, updated and removed from the storage. Iteration over all items in the storage is also supported.

Utility functions

char *jstore_readfp(FILE *fp)#: Read stream into an allocated buffer. Returns a pointer to the buffer or NULL on error.

char *jstore_readfile(const char *filename)#: Read file into an allocated buffer. Returns a pointer to the buffer or NULL on error.

char *jstore_readfile_to_jsmn(const char *filename, jsmntok_t **tokens_ptr, unsigned int *num_tokens_ptr)#

Read file into an allocated buffer and parse it with JSMN.

The tokens_ptr and num_tokens_ptr arguments are passed on to jsmn_parse_alloc().

Returns a pointer to the buffer or NULL on error.

JStore API

JStore *jstore_open(void)#: Create a new JSON store and return it. Returns NULL on error.

int jstore_close(JStore *js)#: Close JSON store. Returns non-zero on error.

int jstore_add(JStore *js, const char *key, const char *value)#: Add JSON value to store with given key. If key already exists, it is replaced. Returns non-zero on error.

int jstore_addn(JStore *js, const char *key, size_t klen, const char *value, size_t vlen)#: Add JSON value to store with given key. The lengths of the key and value are provided by klen and vlen, respectively. If the strings are NUL-terminated, the corresponding length may be set to zero. If key already exists, it is replaced. Returns non-zero on error.

int jstore_addstolen(JStore *js, const char *key, const char *value)#: Add JSON value to store with given key. The store “steels” the ownership of the memory pointed to by value. If key already exists, it is replaced. Returns non-zero on error.

const char *jstore_get(JStore *js, const char *key)#: Returns JSON value for given key or NULL if the key isn’t in the store. This function can also be used to check if a key exists in the store.

int jstore_remove(JStore *js, const char *key)#: Removes item corresponding to given key from JSON store.

int jstore_update(JStore *js, JStore *other)#: Update JSON store with values from other. Return non-zero on error.

int jstore_update_from_jsmn(JStore *js, const char *src, jsmntok_t *tok)#: Update JSON store with values from JSMN token tok. The JSMN token must be an object. Return non-zero on error.

int jstore_update_from_string(JStore *js, const char *buf, int len)#: Update JSON store with values from string buf. Return non-zero on error.

int jstore_update_from_file(JStore *js, const char *filename)#: Update JSON store with values from file filename. Return non-zero on error.

int jstore_update_file(JStore *js, const char *filename)#: Update filename from JSON store. The file is first read and then rewritten while the store is unchanged. Return non-zero on error.

char *jstore_to_string(JStore *js)#: Returns a malloc()’ed JSON string with the content of the store or NULL on error.

int jstore_to_file(JStore *js, const char *filename)#: Writes JSON store to file. If filename exists, it is overwritten. Returns non-zero on error.

int jstore_count(JStore *js)#: Return number of elements in the store.

const char *jstore_get_single_key(JStore *js)#: If there is one item in the store, return a borrowed pointer to its key. Otherwise return NULL.

int jstore_iter_init(JStore *js, JStoreIter *iter)#: Initialise iterator. Return non-zero on error.

const char *jstore_iter_next(JStoreIter *iter)#: Returns the key to the next item in or NULL if there are no more items in the store. Use jstore_get() to get the corresponding value.

int jstore_iter_deinit(JStoreIter *iter)#: Deinitialise the iterator. Returns non-zero on error. In the current implementation, this function does nothing.

int jstore_set_labeln(JStore *js, const char *key, const char *label, int len)#: Associate label with key. If len is non-negative, it is the length of label; otherwise label is assumed to be NUL-terminated. If key already has a label, the old label is replaced. Returns non-zero on error.

int jstore_set_label(JStore *js, const char *key, const char *label)#: Associate label with key. If key already has a label, the old label is replaced. Returns non-zero on error.

const char *jstore_get_label(JStore *js, const char *key)#: Returns a pointer to label associated with key or NULL if key has no associated label.

Typedefs

typedef struct _JStore JStore#: JStore object

typedef struct _JStoreIter JStoreIter#: JStore iterator object

struct _JStoreIter#

#include <jstore.h>

JStore iterator object

Public Members

JStore *js#

map_iter_t miter#

jstore

Contents

jstore#