From a00c94824126901168bca5b89147f9e334a49e87 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Tue, 13 Oct 2015 13:37:40 +0100 Subject: [PATCH] qom: Introduce ObjectPropertyIterator struct for iteration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some users of QOM need to be able to iterate over properties defined against an object instance. Currently they are just directly using the QTAIL macros against the object properties data structure. This is bad because it exposes them to changes in the data structure used to store properties, as well as changes in functionality such as ability to register properties against the class. This provides an ObjectPropertyIterator struct which will insulate the callers from the particular data structure used to store properties. It can be used thus ObjectProperty *prop; ObjectPropertyIterator *iter; iter = object_property_iter_init(obj); while ((prop = object_property_iter_next(iter))) { ... do something with prop ... } object_property_iter_free(iter); Signed-off-by: Daniel P. Berrange Tested-by: Pavel Fedin [AF: Fixed examples, style cleanups] Signed-off-by: Andreas Färber --- include/qom/object.h | 49 ++++++++++++++++++++++++++++++++++++++ qom/object.c | 28 ++++++++++++++++++++++ tests/check-qom-proplist.c | 46 +++++++++++++++++++++++++++++++++++ 3 files changed, 123 insertions(+) diff --git a/include/qom/object.h b/include/qom/object.h index 0bb89d481e..9f703140bd 100644 --- a/include/qom/object.h +++ b/include/qom/object.h @@ -960,6 +960,55 @@ void object_property_del(Object *obj, const char *name, Error **errp); ObjectProperty *object_property_find(Object *obj, const char *name, Error **errp); +typedef struct ObjectPropertyIterator ObjectPropertyIterator; + +/** + * object_property_iter_init: + * @obj: the object + * + * Initializes an iterator for traversing all properties + * registered against an object instance. + * + * It is forbidden to modify the property list while iterating, + * whether removing or adding properties. + * + * Typical usage pattern would be + * + * + * Using object property iterators + * + * ObjectProperty *prop; + * ObjectPropertyIterator *iter; + * + * iter = object_property_iter_init(obj); + * while ((prop = object_property_iter_next(iter))) { + * ... do something with prop ... + * } + * object_property_iter_free(iter); + * + * + * + * Returns: the new iterator + */ +ObjectPropertyIterator *object_property_iter_init(Object *obj); + +/** + * object_property_iter_free: + * @iter: the iterator instance + * + * Releases any resources associated with the iterator. + */ +void object_property_iter_free(ObjectPropertyIterator *iter); + +/** + * object_property_iter_next: + * @iter: the iterator instance + * + * Returns: the next property, or %NULL when all properties + * have been traversed. + */ +ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter); + void object_unparent(Object *obj); /** diff --git a/qom/object.c b/qom/object.c index c0decb6e96..1c926ceea1 100644 --- a/qom/object.c +++ b/qom/object.c @@ -67,6 +67,10 @@ struct TypeImpl InterfaceImpl interfaces[MAX_INTERFACES]; }; +struct ObjectPropertyIterator { + ObjectProperty *next; +}; + static Type type_interface; static GHashTable *type_table_get(void) @@ -917,6 +921,30 @@ ObjectProperty *object_property_find(Object *obj, const char *name, return NULL; } +ObjectPropertyIterator *object_property_iter_init(Object *obj) +{ + ObjectPropertyIterator *ret = g_new0(ObjectPropertyIterator, 1); + ret->next = QTAILQ_FIRST(&obj->properties); + return ret; +} + +void object_property_iter_free(ObjectPropertyIterator *iter) +{ + if (!iter) { + return; + } + g_free(iter); +} + +ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter) +{ + ObjectProperty *ret = iter->next; + if (ret) { + iter->next = QTAILQ_NEXT(iter->next, node); + } + return ret; +} + void object_property_del(Object *obj, const char *name, Error **errp) { ObjectProperty *prop = object_property_find(obj, name, errp); diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c index 7400b1fce9..1be8b9e6f2 100644 --- a/tests/check-qom-proplist.c +++ b/tests/check-qom-proplist.c @@ -283,6 +283,51 @@ static void test_dummy_getenum(void) &err); g_assert(err != NULL); error_free(err); + + object_unparent(OBJECT(dobj)); +} + + +static void test_dummy_iterator(void) +{ + Object *parent = object_get_objects_root(); + DummyObject *dobj = DUMMY_OBJECT( + object_new_with_props(TYPE_DUMMY, + parent, + "dummy0", + &error_abort, + "bv", "yes", + "sv", "Hiss hiss hiss", + "av", "platypus", + NULL)); + + ObjectProperty *prop; + ObjectPropertyIterator *iter; + bool seenbv = false, seensv = false, seenav = false, seentype; + + iter = object_property_iter_init(OBJECT(dobj)); + while ((prop = object_property_iter_next(iter))) { + if (g_str_equal(prop->name, "bv")) { + seenbv = true; + } else if (g_str_equal(prop->name, "sv")) { + seensv = true; + } else if (g_str_equal(prop->name, "av")) { + seenav = true; + } else if (g_str_equal(prop->name, "type")) { + /* This prop comes from the base Object class */ + seentype = true; + } else { + g_printerr("Found prop '%s'\n", prop->name); + g_assert_not_reached(); + } + } + object_property_iter_free(iter); + g_assert(seenbv); + g_assert(seenav); + g_assert(seensv); + g_assert(seentype); + + object_unparent(OBJECT(dobj)); } @@ -297,6 +342,7 @@ int main(int argc, char **argv) g_test_add_func("/qom/proplist/createv", test_dummy_createv); g_test_add_func("/qom/proplist/badenum", test_dummy_badenum); g_test_add_func("/qom/proplist/getenum", test_dummy_getenum); + g_test_add_func("/qom/proplist/iterator", test_dummy_iterator); return g_test_run(); }