Constify char * arguments of APIs

Closes GH-5676.

1 files changed, 2 insertions, 2 deletions

diff --git a/ext/json/php_json.h b/ext/json/php_json.h
index 4fc7ded7d4..ee8affa1d1 100644
--- a/ext/json/php_json.h
+++ b/ext/json/php_json.h
@@ -98,9 +98,9 @@ ZEND_TSRMLS_CACHE_EXTERN()
 
 PHP_JSON_API int php_json_encode_ex(smart_str *buf, zval *val, int options, zend_long depth);
 PHP_JSON_API int php_json_encode(smart_str *buf, zval *val, int options);
-PHP_JSON_API int php_json_decode_ex(zval *return_value, char *str, size_t str_len, zend_long options, zend_long depth);
+PHP_JSON_API int php_json_decode_ex(zval *return_value, const char *str, size_t str_len, zend_long options, zend_long depth);
 
-static inline int php_json_decode(zval *return_value, char *str, int str_len, zend_bool assoc, zend_long depth)
+static inline int php_json_decode(zval *return_value, const char *str, int str_len, zend_bool assoc, zend_long depth)
 {
 	return php_json_decode_ex(return_value, str, str_len, assoc ? PHP_JSON_OBJECT_AS_ARRAY : 0, depth);
 }