/*

 * $Id: json_util.h,v 1.4 2006/01/30 23:07:57 mclark Exp $

 *

 * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd.

 * Michael Clark <michael@metaparadigm.com>

 *

 * 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 Miscllaneous utility functions and macros.

 */ 

#ifndef _json_util_h_

#define _json_util_h_

#include "json_object.h"

#ifndef json_min

#define json_min(a,b) ((a) < (b) ? (a) : (b))

#endif

#ifndef json_max

#define json_max(a,b) ((a) > (b) ? (a) : (b))

#endif

#ifdef __cplusplus

extern "C" {

#endif

#define JSON_FILE_BUF_SIZE 4096

/* utility functions */

/**

 * Read the full contents of the given file, then convert it to a

 * json_object using json_tokener_parse().

 *

 * Returns -1 if something fails.  See json_util_get_last_err() for details.

 */

extern struct json_object* json_object_from_file(const char *filename);

/**

 * Create a JSON object from already opened file descriptor.

 *

 * This function can be helpful, when you opened the file already,

 * e.g. when you have a temp file.

 * Note, that the fd must be readable at the actual position, i.e.

 * use lseek(fd, 0, SEEK_SET) before.

 *

 * Returns -1 if something fails.  See json_util_get_last_err() for details.

 */

extern struct json_object* json_object_from_fd(int fd);

/**

 * Equivalent to:

 *   json_object_to_file_ext(filename, obj, JSON_C_TO_STRING_PLAIN);

 *

 * Returns -1 if something fails.  See json_util_get_last_err() for details.

 */

extern int json_object_to_file(const char *filename, struct json_object *obj);

/**

 * Open and truncate the given file, creating it if necessary, then

 * convert the json_object to a string and write it to the file.

 *

 * Returns -1 if something fails.  See json_util_get_last_err() for details.

 */

extern int json_object_to_file_ext(const char *filename, struct json_object *obj, int flags);

/**

 * Convert the json_object to a string and write it to the file descriptor.

 * Handles partial writes and will keep writing until done, or an error

 * occurs.

 *

 * @param fd an open, writable file descriptor to write to

 * @param obj the object to serializer and write

 * @param flags flags to pass to json_object_to_json_string_ext()

 * @return -1 if something fails.  See json_util_get_last_err() for details.

 */

extern int json_object_to_fd(int fd, struct json_object *obj, int flags);

/**

 * Return the last error from various json-c functions, including:

 * json_object_to_file{,_ext}, json_object_to_fd() or

 * json_object_from_{file,fd}, or NULL if there is none.

 */

const char *json_util_get_last_err(void);

extern int json_parse_int64(const char *buf, int64_t *retval);

extern int json_parse_double(const char *buf, double *retval);

/**

 * Return a string describing the type of the object.

 * e.g. "int", or "object", etc...

 */

extern const char *json_type_to_name(enum json_type o_type);

#ifdef __cplusplus

}

#endif

#endif