FUNCTIONS

#include "mjson.h"

int json_read_object(const char *, const struct json_attr_t *, const char **);

int json_read_array(const char *, const struct json_array_t *, const char **);

const char *json_error_string(int);

void json_enable_debug(int, FILE *);

DESCRIPTION

json_read_object() attempts to parse a whole JSON object from the buffer pointed at by the first argument. The second argument points at an array of template structures describing the expected shape of the JSON object (that is, the set of attribute names and their expected value types. order-independent) and specifying for each attribute a C address where the parsed value should be delivered. The third argument, if non-null, is where a copy of a pointer to just past the parsed object is placed.

Objects may contain objects or arrays as attribute values, and an array may be composed of JSON objects. These functions mutually recurse as required. (Arrays within arrays are currently not supported; this may change in a future release.)

void json_enable_debug(int, FILE *) enables the generation of trace messages to the indicated file pointer while parsing.

For details on how to build template structures, consult the document Building Static JSON Parsers With Microjson shipped with the distribution.

RETURN VALUE

The two main functions return 0 for success, a nonzero error code for failure. The function json_error_string() maps error codes to explanatory messages.

When an error is returned and the end pointer (third) argument is non-null, it is filled with the value of the buffer pointer at the time the error was thrown.

BUGS

A backslash escape of "\0000" in a string value will drop a NUL in the string that is likely to confuse C code looking at the storage. In general, the high byte of a \uxxxxx escape will be ignored and the ASCII high-half byte named by the last two hex digits will be inserted in the string.

There is no way to make a parser accept the typeless special JSON value "null", because there is nothing in C’s type ontology to map it to.

JSON arrays are restricted to having a single homogenous element type. However, the type may itself be a JSON object.

REPORTING BUGS

Report bugs to Eric S. Raymond <esr@thyrsus.com>. The project page is at http://catb.org/~esr/microjson