ObjFW  Check-in [d60c3ae1ec]

 *          assumptions about the object returned by this method if you don't
 *          want your program to terminate due to a message not understood, but
 *          instead check the returned object using @ref isKindOfClass:.
 *
 * @return An object
 */
- (id)JSONValue;

/*!
 * @brief Creates an object from the JSON value of the string.
 *
 * @note This also allows parsing JSON5, an extension of JSON. See
 *	 http://json5.org/ for more details.
 *
 * @warning Although not specified by the JSON specification, this can also
 *          return primitives like strings and numbers. The rationale behind
 *          this is that most JSON parsers allow JSON data just consisting of a
 *          single primitive, leading to realworld JSON files sometimes only
 *          consisting of a single primitive. Therefore, you should not make any
 *          assumptions about the object returned by this method if you don't
 *          want your program to terminate due to a message not understood, but
 *          instead check the returned object using @ref isKindOfClass:.
 *
 * @brief depthLimit The maximum depth the parser should accept (defaults to 32
 *		     if not specified, 0 means no limit (insecure!))
 *
 * @return An object
 */
- (id)JSONValueWithDepthLimit: (size_t)depthLimit;
@end

#import "OFInvalidJSONException.h"

#import "macros.h"

int _OFString_JSONValue_reference;

static id nextObject(const char *restrict *, const char*,
    size_t *restrict line, size_t depth, size_t depthLimit);

static void
skipWhitespaces(const char *restrict *pointer, const char *stop,
    size_t *restrict line)
{
	while (*pointer < stop && (**pointer == ' ' || **pointer == '\t' ||
	    **pointer == '\r' || **pointer == '\n')) {

	 * reach stop.
	 */
	return nil;
}

static inline OFMutableArray*
parseArray(const char *restrict *pointer, const char *stop,
    size_t *restrict line, size_t depth, size_t depthLimit)
{
	OFMutableArray *array = [OFMutableArray array];

	if (++(*pointer) >= stop)
		return nil;

	if (++depth > depthLimit)
		return nil;

	while (**pointer != ']') {
		id object;

		skipWhitespacesAndComments(pointer, stop, line);
		if (*pointer >= stop)
			return nil;

			if (*pointer >= stop || **pointer != ']')
				return nil;

			break;
		}

		object = nextObject(pointer, stop, line, depth, depthLimit);
		if (object == nil)
			return nil;

		[array addObject: object];

		skipWhitespacesAndComments(pointer, stop, line);
		if (*pointer >= stop)
			return nil;

	(*pointer)++;

	return array;
}

static inline OFMutableDictionary*
parseDictionary(const char *restrict *pointer, const char *stop,
    size_t *restrict line, size_t depth, size_t depthLimit)
{
	OFMutableDictionary *dictionary = [OFMutableDictionary dictionary];

	if (++(*pointer) >= stop)
		return nil;

	if (++depth > depthLimit)
		return nil;

	while (**pointer != '}') {
		id key, object;

		skipWhitespacesAndComments(pointer, stop, line);
		if (*pointer >= stop)
			return nil;

			return nil;

		if ((**pointer >= 'a' && **pointer <= 'z') ||
		    (**pointer >= 'A' && **pointer <= 'Z') ||
		    **pointer == '_' || **pointer == '$' || **pointer == '\\')
			key = parseIdentifier(pointer, stop);
		else
			key = nextObject(pointer, stop, line,
			    depth, depthLimit);

		if (key == nil)
			return nil;

		skipWhitespacesAndComments(pointer, stop, line);
		if (*pointer + 1 >= stop || **pointer != ':')
			return nil;

		(*pointer)++;

		object = nextObject(pointer, stop, line, depth, depthLimit);
		if (object == nil)
			return nil;

		[dictionary setObject: object
			       forKey: key];

		skipWhitespacesAndComments(pointer, stop, line);
		if (*pointer >= stop)

	}

	return number;
}

static id
nextObject(const char *restrict *pointer, const char *stop,
    size_t *restrict line, size_t depth, size_t depthLimit)
{
	skipWhitespacesAndComments(pointer, stop, line);

	if (*pointer >= stop)
		return nil;

	switch (**pointer) {
	case '"':
	case '\'':
		return parseString(pointer, stop, line);
	case '[':
		return parseArray(pointer, stop, line, depth, depthLimit);
	case '{':
		return parseDictionary(pointer, stop, line, depth, depthLimit);
	case 't':
		if (*pointer + 3 >= stop)
			return nil;

		if (memcmp(*pointer, "true", 4))
			return nil;

		return nil;
	}
}

@implementation OFString (JSONValue)
- (id)JSONValue
{
	return [self JSONValueWithDepthLimit: 32];
}

- (id)JSONValueWithDepthLimit: (size_t)depthLimit
{
	const char *pointer = [self UTF8String];
	const char *stop = pointer + [self UTF8StringLength];
	id object;
	size_t line = 1;

	object = nextObject(&pointer, stop, &line, 0, depthLimit);
	skipWhitespacesAndComments(&pointer, stop, &line);

	if (pointer < stop || object == nil)
		@throw [OFInvalidJSONException exceptionWithClass: [self class]
							     line: line];

	return object;
}
@end