Add json parse and stringify function to jerryscript c api (#2243)

JerryScript-DCO-1.0-Signed-off-by: Zsolt Raduska rzsolt@inf.u-szeged.hu

docs/02.API-REFERENCE.md

@@ -5921,3 +5921,73 @@ jerry_value_t jerry_get_typedarray_buffer (jerry_value_t value,
 **See also**
 
 - [jerry_create_typedarray](#jerry_create_typedarray)
+
+# JSON functions
+
+## jerry_json_parse
+
+**Summary**
+
+Returns the same result as JSON.parse ecmascript function.
+
+**Prototype**
+
+```c
+jerry_value_t jerry_json_parse (const jerry_char_t *string_p, jerry_size_t string_size)
+```
+
+- `string_p` - a JSON string
+- `string_size` - size of the string
+- return
+  - jerry_value_t containing the same as json.parse()
+  - jerry_value_t containing error massage
+
+**Example**
+
+```c
+{
+  const char *data = "{\"name\": \"John\", \"age\": 5}";
+  jerry_size_t str_length = (jerry_size_t)strlen (data);
+  jerry_value_t parsed_json = jerry_json_parse ((jerry_char_t*)data, str_length);
+
+  // parsed_json now conatins all data stored in data_in_json
+
+  jerry_release_value (parsed_json);
+}
+```
+
+## jerry_stringify
+
+  **Summary**
+
+  Returns the same value as JSON.stringify() ecmascript function.
+
+  **Prototype**
+
+```c
+jerry_value_t jerry_json_stringfy (const jerry_value_t object_to_stringify)
+```
+
+- `object_to_stringify` - a jerry_value_t object to stringify
+- return
+  - jerry_value_t containing the same as json.stringify()
+  - jerry_value_t containing error massage
+
+**Example**
+
+```c
+{
+  jerry_value_t obj = jerry_create_object ();
+  jerry_value_t key = jerry_create_string ((const jerry_char_t *) "name");
+  jerry_value_t value = jerry_create_string ((const jerry_char_t *) "John");
+  jerry_set_property (obj, key, value);
+  jerry_value_t stringified = jerry_json_stringfy (obj);
+
+  //stringified now contains a json formated string
+
+  jerry_release_value (obj);
+  jerry_release_value (key);
+  jerry_release_value (value);
+  jerry_release_value (stringified);
+}
+```

jerry-core/api/jerry.c

@@ -3412,6 +3412,63 @@ jerry_get_typedarray_buffer (jerry_value_t value, /**< TypedArray to get the arr
 #endif /* !CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN */
 } /* jerry_get_typedarray_buffer */
 
+/**
+ * Create an object from JSON
+ *
+ * Note:
+ *      The returned value must be freed with jerry_release_value
+ * @return jerry_value_t from json formated string or an error massage
+ */
+jerry_value_t
+jerry_json_parse (const jerry_char_t *string_p, /**< json string */
+                  jerry_size_t string_size) /**< json string size */
+{
+  jerry_assert_api_available ();
+
+#ifndef CONFIG_DISABLE_JSON_BUILTIN
+  ecma_value_t ret_value = ecma_builtin_json_parse_buffer (string_p, string_size);
+
+  if (ecma_is_value_undefined (ret_value))
+  {
+    ret_value = jerry_throw (ecma_raise_syntax_error (ECMA_ERR_MSG ("JSON string parse error.")));
+  }
+
+  return ret_value;
+#else /* CONFIG_DISABLE_JSON_BUILTIN */
+  JERRY_UNUSED (string_p);
+  JERRY_UNUSED (string_size);
+
+  return jerry_throw (ecma_raise_syntax_error (ECMA_ERR_MSG ("The JSON has been disabled.")));
+#endif /* !CONFIG_DISABLE_JSON_BUILTIN */
+} /* jerry_json_parse */
+
+/**
+ * Create a Json formated string from an object
+ *
+ * Note:
+ *      The returned value must be freed with jerry_release_value
+ * @return json formated jerry_value_t or an error massage
+ */
+jerry_value_t
+jerry_json_stringfy (const jerry_value_t object_to_stringify) /**< a jerry_object_t to stringify */
+{
+  jerry_assert_api_available ();
+#ifndef CONFIG_DISABLE_JSON_BUILTIN
+  ecma_value_t ret_value = ecma_builtin_json_string_from_object (object_to_stringify);
+
+  if (ecma_is_value_undefined (ret_value))
+  {
+    ret_value = jerry_throw (ecma_raise_syntax_error (ECMA_ERR_MSG ("JSON stringify error.")));
+  }
+
+  return ret_value;
+#else /* CONFIG_DISABLE_JSON_BUILTIN */
+  JERRY_UNUSED (object_to_stringify);
+
+  return jerry_throw (ecma_raise_syntax_error (ECMA_ERR_MSG ("The JSON has been disabled.")));
+#endif /* !CONFIG_DISABLE_JSON_BUILTIN */
+} /* jerry_json_stringfy */
+
 /**
  * @}
  */

jerry-core/ecma/builtin-objects/ecma-builtin-helpers-json.c

@@ -18,6 +18,8 @@
 #include "ecma-builtin-helpers.h"
 #include "lit-char-helpers.h"
 
+#ifndef CONFIG_DISABLE_JSON_BUILTIN
+
 /** \addtogroup ecma ECMA
  * @{
  *
@@ -221,6 +223,8 @@ ecma_builtin_helper_json_create_non_formatted_json (lit_utf8_byte_t left_bracket
   return ecma_make_string_value (result_str_p);
 } /* ecma_builtin_helper_json_create_non_formatted_json */
 
+#endif /* !CONFIG_DISABLE_JSON_BUILTIN */
+
 /**
  * @}
  * @}

jerry-core/ecma/builtin-objects/ecma-builtin-helpers.h

@@ -152,6 +152,9 @@ typedef struct
   ecma_object_t *replacer_function_p;
 } ecma_json_stringify_context_t;
 
+ecma_value_t ecma_builtin_json_parse_buffer (const lit_utf8_byte_t * str_start_p,
+                                             lit_utf8_size_t string_size);
+ecma_value_t ecma_builtin_json_string_from_object (const ecma_value_t arg1);
 bool ecma_json_has_object_in_stack (ecma_json_occurence_stack_item_t *stack_p, ecma_object_t *object_p);
 bool ecma_has_string_value_in_collection (ecma_collection_header_t *collection_p, ecma_value_t string_value);
 

jerry-core/ecma/builtin-objects/ecma-builtin-json.c

@@ -805,6 +805,35 @@ ecma_builtin_json_walk (ecma_object_t *reviver_p, /**< reviver function */
   return ret_value;
 } /* ecma_builtin_json_walk */
 
+/**
+ * Function to set a string token from the given arguments, fills its fields and advances the string pointer.
+ *
+ * @return ecma_value_t containing an object or an error massage
+ *         Returned value must be freed with ecma_free_value.
+ */
+ecma_value_t
+ecma_builtin_json_parse_buffer (const lit_utf8_byte_t * str_start_p, /**< String to parse */
+                                lit_utf8_size_t string_size) /**< size of the string */
+{
+  ecma_json_token_t token;
+  token.current_p = str_start_p;
+  token.end_p = str_start_p + string_size;
+
+  ecma_value_t final_result = ecma_builtin_json_parse_value (&token);
+
+  if (!ecma_is_value_undefined (final_result))
+  {
+    ecma_builtin_json_parse_next_token (&token, false);
+
+    if (token.type != end_token)
+    {
+      ecma_free_value (final_result);
+      final_result = ECMA_VALUE_UNDEFINED;
+    }
+  }
+  return final_result;
+} /*ecma_builtin_json_parse_buffer*/
+
 /**
  * The JSON object's 'parse' routine
  *
@@ -830,22 +859,7 @@ ecma_builtin_json_parse (ecma_value_t this_arg, /**< 'this' argument */
 
   ECMA_STRING_TO_UTF8_STRING (string_p, str_start_p, string_size);
 
-  ecma_json_token_t token;
-  token.current_p = str_start_p;
-  token.end_p = str_start_p + string_size;
-
-  ecma_value_t final_result = ecma_builtin_json_parse_value (&token);
-
-  if (!ecma_is_value_undefined (final_result))
-  {
-    ecma_builtin_json_parse_next_token (&token, false);
-
-    if (token.type != end_token)
-    {
-      ecma_free_value (final_result);
-      final_result = ECMA_VALUE_UNDEFINED;
-    }
-  }
+  ecma_value_t final_result = ecma_builtin_json_parse_buffer (str_start_p, string_size);
 
   if (ecma_is_value_undefined (final_result))
   {
@@ -892,6 +906,61 @@ ecma_builtin_json_object (ecma_object_t *obj_p, ecma_json_stringify_context_t *c
 static ecma_value_t
 ecma_builtin_json_array (ecma_object_t *obj_p, ecma_json_stringify_context_t *context_p);
 
+/**
+ * Helper function to stringify an object in JSON format representing an ecma_value.
+ *
+ *  @return ecma_value_t string created from an abject formating by a given context
+ *          Returned value must be freed with ecma_free_value.
+ *
+ */
+static ecma_value_t ecma_builtin_json_str_helper (const ecma_value_t arg1, /**< object argument */
+                                                  ecma_json_stringify_context_t context) /**< context argument */
+{
+  ecma_value_t ret_value = ECMA_VALUE_EMPTY;
+  ecma_object_t *obj_wrapper_p = ecma_op_create_object_object_noarg ();
+  ecma_string_t *empty_str_p = ecma_get_magic_string (LIT_MAGIC_STRING__EMPTY);
+  ecma_value_t put_comp_val = ecma_op_object_put (obj_wrapper_p,
+                                                  empty_str_p,
+                                                  arg1,
+                                                  false);
+  JERRY_ASSERT (ecma_is_value_true (put_comp_val));
+  ecma_free_value (put_comp_val);
+  ECMA_TRY_CATCH (str_val,
+                  ecma_builtin_json_str (empty_str_p, obj_wrapper_p, &context),
+                  ret_value);
+  ret_value = ecma_copy_value (str_val);
+  ECMA_FINALIZE (str_val);
+  ecma_free_value (put_comp_val);
+  ecma_deref_ecma_string (empty_str_p);
+  ecma_deref_object (obj_wrapper_p);
+
+  return ret_value;
+} /* ecma_builtin_json_str_helper */
+
+/**
+ * Function to create a json formated string from an object
+ *
+ * @return ecma_value_t containing a json string
+ *         Returned value must be freed with ecma_free_value.
+ */
+ecma_value_t
+ecma_builtin_json_string_from_object (const ecma_value_t arg1) /**< object argument */
+{
+  ecma_json_stringify_context_t context;
+  context.occurence_stack_last_p = NULL;
+  context.indent_str_p = ecma_get_magic_string (LIT_MAGIC_STRING__EMPTY);
+  context.property_list_p = ecma_new_values_collection ();
+  context.replacer_function_p = NULL;
+  context.gap_str_p = ecma_get_magic_string (LIT_MAGIC_STRING__EMPTY);
+
+  ecma_value_t ret_value = ecma_builtin_json_str_helper (arg1, context);
+
+  ecma_deref_ecma_string (context.gap_str_p);
+  ecma_deref_ecma_string (context.indent_str_p);
+  ecma_free_values_collection (context.property_list_p, 0);
+  return ret_value;
+} /*ecma_builtin_json_string_from_object*/
+
 /**
  * The JSON object's 'stringify' routine
  *
@@ -1119,28 +1188,7 @@ ecma_builtin_json_stringify (ecma_value_t this_arg, /**< 'this' argument */
     if (ecma_is_value_empty (ret_value))
     {
       /* 9. */
-      ecma_object_t *obj_wrapper_p = ecma_op_create_object_object_noarg ();
-      ecma_string_t *empty_str_p = ecma_get_magic_string (LIT_MAGIC_STRING__EMPTY);
-
-      /* 10. */
-      ecma_value_t put_comp_val = ecma_op_object_put (obj_wrapper_p,
-                                                      empty_str_p,
-                                                      arg1,
-                                                      false);
-
-      JERRY_ASSERT (ecma_is_value_true (put_comp_val));
-      ecma_free_value (put_comp_val);
-
-      /* 11. */
-      ECMA_TRY_CATCH (str_val,
-                      ecma_builtin_json_str (empty_str_p, obj_wrapper_p, &context),
-                      ret_value);
-
-      ret_value = ecma_copy_value (str_val);
-
-      ECMA_FINALIZE (str_val);
-
-      ecma_deref_object (obj_wrapper_p);
+      ret_value = ecma_builtin_json_str_helper (arg1, context);
     }
 
     ecma_deref_ecma_string (context.gap_str_p);

jerry-core/include/jerryscript-core.h

@@ -544,6 +544,8 @@ jerry_length_t jerry_get_typedarray_length (jerry_value_t value);
 jerry_value_t jerry_get_typedarray_buffer (jerry_value_t value,
                                            jerry_length_t *byte_offset,
                                            jerry_length_t *byte_length);
+jerry_value_t jerry_json_parse (const jerry_char_t *string_p, jerry_size_t string_size);
+jerry_value_t jerry_json_stringfy (const jerry_value_t object_to_stringify);
 
 /**
  * @}

tests/unit-core/test-api.c

@@ -1139,6 +1139,48 @@ main (void)
 
   jerry_release_value (args[1]);
 
+  {
+    /*json parser check*/
+    char data_check[]="John";
+    jerry_value_t key = jerry_create_string ((const jerry_char_t *) "name");
+    const char *data = "{\"name\": \"John\", \"age\": 5}";
+    jerry_size_t str_length = (jerry_size_t) strlen (data);
+    jerry_value_t parsed_json = jerry_json_parse ((jerry_char_t *) data, str_length);
+    jerry_value_t has_prop_js = jerry_has_property (parsed_json, key);
+    TEST_ASSERT (jerry_get_boolean_value (has_prop_js));
+    jerry_release_value (has_prop_js);
+    jerry_value_t parsed_data = jerry_get_property (parsed_json, key);
+    TEST_ASSERT (jerry_value_is_string (parsed_data)== true);
+    jerry_size_t buff_size = (jerry_size_t) jerry_get_string_length (parsed_data);
+    char buff[jerry_get_string_length (parsed_data)];
+    jerry_char_t *buff_p = (jerry_char_t *) buff;
+    jerry_string_to_char_buffer (parsed_data, buff_p, buff_size);
+    buff[buff_size] = '\0';
+    TEST_ASSERT (strcmp ((const char *) data_check, (const char *) buff) == false);
+    jerry_release_value (parsed_json);
+    jerry_release_value (key);
+    jerry_release_value (parsed_data);
+  }
+
+  /*json stringify test*/
+  {
+    jerry_value_t obj = jerry_create_object ();
+    char check_value[] = "{\"name\":\"John\"}";
+    jerry_value_t key = jerry_create_string ((const jerry_char_t *) "name");
+    jerry_value_t value = jerry_create_string ((const jerry_char_t *) "John");
+    jerry_set_property (obj, key, value);
+    jerry_value_t stringified = jerry_json_stringfy (obj);
+    TEST_ASSERT (jerry_value_is_string (stringified));
+    char buff[jerry_get_string_length (stringified)];
+    jerry_string_to_char_buffer (stringified, (jerry_char_t *) buff,
+                                (jerry_size_t) jerry_get_string_length (stringified));
+    buff[jerry_get_string_length (stringified)] = '\0';
+    TEST_ASSERT (strcmp ((const char *) check_value, (const char *) buff)  == 0);
+    jerry_release_value (stringified);
+    jerry_release_value (obj);
+    jerry_release_value (key);
+    jerry_release_value (value);
+  }
   jerry_cleanup ();
 
   return 0;