diff --git a/cJSON.c b/cJSON.c index 3c3f10b..e3fd23c 100644 --- a/cJSON.c +++ b/cJSON.c @@ -1814,6 +1814,36 @@ CJSON_PUBLIC(void) cJSON_AddItemReferenceToObject(cJSON *object, const char *str cJSON_AddItemToObject(object, string, create_reference(item, &global_hooks)); } +CJSON_PUBLIC(cJSON *) cJSON_DetachItemViaPointer(cJSON *parent, cJSON * const item) +{ + if ((parent == NULL) || (item == NULL)) + { + return NULL; + } + + if (item->prev != NULL) + { + /* not the first element */ + item->prev->next = item->next; + } + if (item->next != NULL) + { + /* not the last element */ + item->next->prev = item->prev; + } + + if (item == parent->child) + { + /* first element */ + parent->child = item->next; + } + /* make sure the detached item doesn't point anywhere anymore */ + item->prev = NULL; + item->next = NULL; + + return item; +} + static cJSON *DetachItemFromArray(cJSON *array, size_t which) { cJSON *c = array->child; diff --git a/cJSON.h b/cJSON.h index 1ef70f0..69868b0 100644 --- a/cJSON.h +++ b/cJSON.h @@ -203,6 +203,7 @@ CJSON_PUBLIC(void) cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item); CJSON_PUBLIC(void) cJSON_AddItemReferenceToObject(cJSON *object, const char *string, cJSON *item); /* Remove/Detatch items from Arrays/Objects. */ +CJSON_PUBLIC(cJSON *) cJSON_DetachItemViaPointer(cJSON *parent, cJSON * const item); CJSON_PUBLIC(cJSON *) cJSON_DetachItemFromArray(cJSON *array, int which); CJSON_PUBLIC(void) cJSON_DeleteItemFromArray(cJSON *array, int which); CJSON_PUBLIC(cJSON *) cJSON_DetachItemFromObject(cJSON *object, const char *string); diff --git a/tests/misc_tests.c b/tests/misc_tests.c index 249500d..31a115b 100644 --- a/tests/misc_tests.c +++ b/tests/misc_tests.c @@ -218,6 +218,45 @@ static void cjson_set_number_value_should_set_numbers(void) TEST_ASSERT_EQUAL_DOUBLE(-1 + (double)INT_MIN, number->valuedouble); } +static void cjson_detach_item_via_pointer_should_detach_items(void) +{ + cJSON list[4]; + cJSON parent[1]; + + memset(list, '\0', sizeof(list)); + + /* link the list */ + list[0].next = &(list[1]); + list[1].next = &(list[2]); + list[2].next = &(list[3]); + + list[3].prev = &(list[2]); + list[2].prev = &(list[1]); + list[1].prev = &(list[0]); + + parent->child = &list[0]; + + /* detach in the middle (list[1]) */ + TEST_ASSERT_TRUE_MESSAGE(cJSON_DetachItemViaPointer(parent, &(list[1])) == &(list[1]), "Failed to detach in the middle."); + TEST_ASSERT_TRUE_MESSAGE((list[1].prev == NULL) && (list[1].next == NULL), "Didn't set pointers of detached item to NULL."); + TEST_ASSERT_TRUE((list[0].next == &(list[2])) && (list[2].prev == &(list[0]))); + + /* detach beginning (list[0]) */ + TEST_ASSERT_TRUE_MESSAGE(cJSON_DetachItemViaPointer(parent, &(list[0])) == &(list[0]), "Failed to detach beginning."); + TEST_ASSERT_TRUE_MESSAGE((list[0].prev == NULL) && (list[0].next == NULL), "Didn't set pointers of detached item to NULL."); + TEST_ASSERT_TRUE_MESSAGE((list[2].prev == NULL) && (parent->child == &(list[2])), "Didn't set the new beginning."); + + /* detach end (list[3])*/ + TEST_ASSERT_TRUE_MESSAGE(cJSON_DetachItemViaPointer(parent, &(list[3])) == &(list[3]), "Failed to detach end."); + TEST_ASSERT_TRUE_MESSAGE((list[3].prev == NULL) && (list[3].next == NULL), "Didn't set pointers of detached item to NULL."); + TEST_ASSERT_TRUE_MESSAGE((list[2].next == NULL) && (parent->child == &(list[2])), "Didn't set the new end"); + + /* detach single item (list[2]) */ + TEST_ASSERT_TRUE_MESSAGE(cJSON_DetachItemViaPointer(parent, &list[2]) == &list[2], "Failed to detach single item."); + TEST_ASSERT_TRUE_MESSAGE((list[2].prev == NULL) && (list[2].next == NULL), "Didn't set pointers of detached item to NULL."); + TEST_ASSERT_NULL_MESSAGE(parent->child, "Child of the parent wasn't set to NULL."); +} + int main(void) { UNITY_BEGIN(); @@ -229,6 +268,7 @@ int main(void) RUN_TEST(typecheck_functions_should_check_type); RUN_TEST(cjson_should_not_parse_to_deeply_nested_jsons); RUN_TEST(cjson_set_number_value_should_set_numbers); + RUN_TEST(cjson_detach_item_via_pointer_should_detach_items); return UNITY_END(); }