xref: /freebsd-src/lib/libpmc/pmu-events/jsmn.h (revision 2a63c3be158216222d89a073dcbd6a72ee4aab5a)

/* SPDX-License-Identifier: MIT */
#ifndef __JSMN_H_
#define __JSMN_H_

/*
 * JSON type identifier. Basic types are:
 *	o Object
 *	o Array
 *	o String
 *	o Other primitive: number, boolean (true/false) or null
 */
typedef enum {
	JSMN_PRIMITIVE = 0,
	JSMN_OBJECT = 1,
	JSMN_ARRAY = 2,
	JSMN_STRING = 3
} jsmntype_t;

typedef enum {
	/* Not enough tokens were provided */
	JSMN_ERROR_NOMEM = -1,
	/* Invalid character inside JSON string */
	JSMN_ERROR_INVAL = -2,
	/* The string is not a full JSON packet, more bytes expected */
	JSMN_ERROR_PART = -3,
	/* Everything was fine */
	JSMN_SUCCESS = 0
} jsmnerr_t;

/*
 * JSON token description.
 * @param		type	type (object, array, string etc.)
 * @param		start	start position in JSON data string
 * @param		end		end position in JSON data string
 */
typedef struct {
	jsmntype_t type;
	int start;
	int end;
	int size;
} jsmntok_t;

/*
 * JSON parser. Contains an array of token blocks available. Also stores
 * the string being parsed now and current position in that string
 */
typedef struct {
	unsigned int pos; /* offset in the JSON string */
	int toknext; /* next token to allocate */
	int toksuper; /* superior token node, e.g parent object or array */
} jsmn_parser;

/*
 * Create JSON parser over an array of tokens
 */
void jsmn_init(jsmn_parser *parser);

/*
 * Run JSON parser. It parses a JSON data string into and array of tokens,
 * each describing a single JSON object.
 */
jsmnerr_t jsmn_parse(jsmn_parser *parser, const char *js,
		     size_t len,
		     jsmntok_t *tokens, unsigned int num_tokens);

const char *jsmn_strerror(jsmnerr_t err);

#endif /* __JSMN_H_ */