php-src/ext/json/json_parser.y

%code top {
/*
  +----------------------------------------------------------------------+
  | PHP Version 7                                                        |
  +----------------------------------------------------------------------+
  | Copyright (c) 1997-2015 The PHP Group                                |
  +----------------------------------------------------------------------+
  | This source file is subject to version 3.01 of the PHP license,      |
  | that is bundled with this package in the file LICENSE, and is        |
  | available through the world-wide-web at the following url:           |
  | http://www.php.net/license/3_01.txt                                  |
  | If you did not receive a copy of the PHP license and are unable to   |
  | obtain it through the world-wide-web, please send a note to          |
  | license@php.net so we can mail you a copy immediately.               |
  +----------------------------------------------------------------------+
  | Author: Jakub Zelenka <bukka@php.net>                                |
  +----------------------------------------------------------------------+
*/

#include "php.h"
#include "php_json.h"
#include "php_json_parser.h"

#define YYDEBUG 0

#if YYDEBUG
int json_yydebug = 1;
#endif

#ifdef _MSC_VER
#define YYMALLOC malloc
#define YYFREE free
#endif

#define PHP_JSON_USE(uv) ((void) (uv))
#define PHP_JSON_USE_1(uvr, uv1) PHP_JSON_USE(uvr); PHP_JSON_USE(uv1)
#define PHP_JSON_USE_2(uvr, uv1, uv2) PHP_JSON_USE(uvr); PHP_JSON_USE(uv1); PHP_JSON_USE(uv2)

}

%pure-parser
%name-prefix "php_json_yy"
%lex-param  { php_json_parser *parser  }
%parse-param { php_json_parser *parser }

%union {
	zval value;
	struct {
		zend_string *key;
		zval val;
	} pair;
}


%token <value> PHP_JSON_T_NUL
%token <value> PHP_JSON_T_TRUE
%token <value> PHP_JSON_T_FALSE
%token <value> PHP_JSON_T_INT
%token <value> PHP_JSON_T_DOUBLE
%token <value> PHP_JSON_T_STRING
%token <value> PHP_JSON_T_ESTRING
%token <value> PHP_JSON_T_EOI
%token <value> PHP_JSON_T_ERROR

%type <value> start object key value array errlex
%type <value> members member elements element
%type <pair> pair

%destructor { zval_dtor(&$$); } <value>
%destructor { zend_string_release($$.key); zval_dtor(&$$.val); } <pair>

%code {
int php_json_yylex(union YYSTYPE *value, php_json_parser *parser);
void php_json_yyerror(php_json_parser *parser, char const *msg);
void php_json_parser_object_init(php_json_parser *parser, zval *object);
int php_json_parser_object_update(php_json_parser *parser, zval *object, zend_string *key, zval *zvalue);
void php_json_parser_array_init(zval *object);
void php_json_parser_array_append(zval *array, zval *zvalue);

#define PHP_JSON_DEPTH_DEC --parser->depth
#define PHP_JSON_DEPTH_INC \
	if (parser->max_depth && parser->depth >= parser->max_depth) { \
		parser->scanner.errcode = PHP_JSON_ERROR_DEPTH; \
		YYERROR; \
	} \
	++parser->depth
}

%% /* Rules */

start:
		value PHP_JSON_T_EOI
			{
				ZVAL_COPY_VALUE(&$$, &$1);
				ZVAL_COPY_VALUE(parser->return_value, &$1);
				PHP_JSON_USE($2); YYACCEPT;
			}
	|	value errlex
			{
				PHP_JSON_USE_2($$, $1, $2);
			}
;

object:
		'{' { PHP_JSON_DEPTH_INC; } members object_end
			{
				PHP_JSON_DEPTH_DEC;
				$$ = $3;
			}
;

object_end:
		'}'
	|	']'
			{
				parser->scanner.errcode = PHP_JSON_ERROR_STATE_MISMATCH;
				YYERROR;
			}
;

members:
		/* empty */
			{
				php_json_parser_object_init(parser, &$$);
			}
	|	member
;

member:
		pair
			{
				php_json_parser_object_init(parser, &$$);
				if (php_json_parser_object_update(parser, &$$, $1.key, &$1.val) == FAILURE)
					YYERROR;
			}
	|	member ',' pair
			{
				if (php_json_parser_object_update(parser, &$1, $3.key, &$3.val) == FAILURE)
					YYERROR;
				ZVAL_COPY_VALUE(&$$, &$1);
			}
	|	member errlex
			{
				PHP_JSON_USE_2($$, $1, $2);
			}
;

pair:
		key ':' value
			{
				$$.key = Z_STR($1);
				ZVAL_COPY_VALUE(&$$.val, &$3);
			}
	|	key errlex
			{
				PHP_JSON_USE_2($$, $1, $2);
			}
;

array:
		'[' { PHP_JSON_DEPTH_INC; } elements array_end
			{
				PHP_JSON_DEPTH_DEC;
				ZVAL_COPY_VALUE(&$$, &$3);
			}
;

array_end:
		']'
	|	'}'
			{
				parser->scanner.errcode = PHP_JSON_ERROR_STATE_MISMATCH;
				YYERROR;
			}
;

elements:
		/* empty */
			{
				php_json_parser_array_init(&$$);
			}
	|	element
;

element:
		value
			{
				php_json_parser_array_init(&$$);
				php_json_parser_array_append(&$$, &$1);
			}
	|	element ',' value
			{
				php_json_parser_array_append(&$1, &$3);
				ZVAL_COPY_VALUE(&$$, &$1);
			}
	|	element errlex
			{
				PHP_JSON_USE_2($$, $1, $2);
			}
;

key:
		PHP_JSON_T_STRING
	|	PHP_JSON_T_ESTRING
;

value:
		object
	|	array
	|	PHP_JSON_T_STRING
	|	PHP_JSON_T_ESTRING
	|	PHP_JSON_T_INT
	|	PHP_JSON_T_DOUBLE
	|	PHP_JSON_T_NUL
	|	PHP_JSON_T_TRUE
	|	PHP_JSON_T_FALSE
	|	errlex
;

errlex:
		PHP_JSON_T_ERROR
			{
				PHP_JSON_USE_1($$, $1);
				YYERROR;
			}
;
	
%% /* Functions */

void php_json_parser_init(php_json_parser *parser, zval *return_value, char *str, size_t str_len, int options, int max_depth)
{
	memset(parser, 0, sizeof(php_json_parser));
	php_json_scanner_init(&parser->scanner, str, str_len, options);
	parser->depth = 1;
	parser->max_depth = max_depth;
	parser->return_value = return_value;
}

php_json_error_code php_json_parser_error_code(php_json_parser *parser)
{
	return parser->scanner.errcode;
}

void php_json_parser_object_init(php_json_parser *parser, zval *object)
{
	if (parser->scanner.options & PHP_JSON_OBJECT_AS_ARRAY) {
		array_init(object);
	} else {
		object_init(object);
	}
}

int php_json_parser_object_update(php_json_parser *parser, zval *object, zend_string *key, zval *zvalue)
{
	/* if JSON_OBJECT_AS_ARRAY is set */
	if (Z_TYPE_P(object) == IS_ARRAY) {
		zend_symtable_update(Z_ARRVAL_P(object), key, zvalue);
	} else {
		zval zkey;
		if (ZSTR_LEN(key) == 0) {
			zend_string_release(key);
			key = zend_string_init("_empty_", sizeof("_empty_") - 1, 0);
		} else if (ZSTR_VAL(key)[0] == '\0') {
			parser->scanner.errcode = PHP_JSON_ERROR_INVALID_PROPERTY_NAME;
			zend_string_release(key);
			zval_dtor(zvalue);
			zval_dtor(object);
			return FAILURE;
		}
		ZVAL_NEW_STR(&zkey, key);
		zend_std_write_property(object, &zkey, zvalue, NULL); 

		if (Z_REFCOUNTED_P(zvalue)) {
			Z_DELREF_P(zvalue);
		}
	}
	zend_string_release(key);

	return SUCCESS;
}

void php_json_parser_array_init(zval *array)
{
	array_init(array);
}

void php_json_parser_array_append(zval *array, zval *zvalue)
{
	zend_hash_next_index_insert(Z_ARRVAL_P(array), zvalue);
}
	
int php_json_yylex(union YYSTYPE *value, php_json_parser *parser)
{
	int token = php_json_scan(&parser->scanner);
	value->value = parser->scanner.value;
	return token;
}

void php_json_yyerror(php_json_parser *parser, char const *msg)
{
	if (!parser->scanner.errcode) {
		parser->scanner.errcode = PHP_JSON_ERROR_SYNTAX;
	}
}