#include "qemu/object.h"
#include "qemu-common.h"
+#include "qapi/qapi-visit-core.h"
+#include "qapi/string-input-visitor.h"
+#include "qapi/string-output-visitor.h"
+
+/* TODO: replace QObject with a simpler visitor to avoid a dependency
+ * of the QOM core on QObject? */
+#include "qemu/qom-qobject.h"
+#include "qobject.h"
+#include "qbool.h"
+#include "qint.h"
+#include "qstring.h"
#define MAX_INTERFACES 32
size_t instance_size;
void (*class_init)(ObjectClass *klass, void *data);
+ void (*class_base_init)(ObjectClass *klass, void *data);
void (*class_finalize)(ObjectClass *klass, void *data);
void *class_data;
#define INTERFACE(obj) OBJECT_CHECK(Interface, obj, TYPE_INTERFACE)
+static Type type_interface;
+
static GHashTable *type_table_get(void)
{
static GHashTable *type_table;
return g_hash_table_lookup(type_table_get(), name);
}
-TypeImpl *type_register(const TypeInfo *info)
+static TypeImpl *type_register_internal(const TypeInfo *info)
{
TypeImpl *ti = g_malloc0(sizeof(*ti));
ti->instance_size = info->instance_size;
ti->class_init = info->class_init;
+ ti->class_base_init = info->class_base_init;
ti->class_finalize = info->class_finalize;
ti->class_data = info->class_data;
return ti;
}
+TypeImpl *type_register(const TypeInfo *info)
+{
+ assert(info->parent);
+ return type_register_internal(info);
+}
+
TypeImpl *type_register_static(const TypeInfo *info)
{
return type_register(info);
return sizeof(ObjectClass);
}
+static size_t type_object_get_size(TypeImpl *ti)
+{
+ if (ti->instance_size) {
+ return ti->instance_size;
+ }
+
+ if (type_has_parent(ti)) {
+ return type_object_get_size(type_get_parent(ti));
+ }
+
+ return 0;
+}
+
static void type_class_interface_init(TypeImpl *ti, InterfaceImpl *iface)
{
TypeInfo info = {
char *name = g_strdup_printf("<%s::%s>", ti->name, iface->parent);
info.name = name;
- iface->type = type_register(&info);
+ iface->type = type_register_internal(&info);
g_free(name);
}
-static void type_class_init(TypeImpl *ti)
+static void type_initialize(TypeImpl *ti)
{
- size_t class_size = sizeof(ObjectClass);
+ TypeImpl *parent;
int i;
if (ti->class) {
}
ti->class_size = type_class_get_size(ti);
+ ti->instance_size = type_object_get_size(ti);
ti->class = g_malloc0(ti->class_size);
- ti->class->type = ti;
- if (type_has_parent(ti)) {
- TypeImpl *parent = type_get_parent(ti);
-
- type_class_init(parent);
+ parent = type_get_parent(ti);
+ if (parent) {
+ type_initialize(parent);
- class_size = parent->class_size;
g_assert(parent->class_size <= ti->class_size);
-
- memcpy((void *)ti->class + sizeof(ObjectClass),
- (void *)parent->class + sizeof(ObjectClass),
- parent->class_size - sizeof(ObjectClass));
+ memcpy(ti->class, parent->class, parent->class_size);
}
- memset((void *)ti->class + class_size, 0, ti->class_size - class_size);
+ ti->class->type = ti;
+
+ while (parent) {
+ if (parent->class_base_init) {
+ parent->class_base_init(ti->class, ti->class_data);
+ }
+ parent = type_get_parent(parent);
+ }
for (i = 0; i < ti->num_interfaces; i++) {
type_class_interface_init(ti, &ti->interfaces[i]);
Object *obj = data;
g_assert(type != NULL);
- g_assert(type->instance_size >= sizeof(ObjectClass));
+ type_initialize(type);
- type_class_init(type);
+ g_assert(type->instance_size >= sizeof(Object));
g_assert(type->abstract == false);
memset(obj, 0, type->instance_size);
obj->class = type->class;
+ QTAILQ_INIT(&obj->properties);
object_init_with_type(obj, type);
}
object_initialize_with_type(data, type);
}
+static inline bool object_property_is_child(ObjectProperty *prop)
+{
+ return strstart(prop->type, "child<", NULL);
+}
+
+static inline bool object_property_is_link(ObjectProperty *prop)
+{
+ return strstart(prop->type, "link<", NULL);
+}
+
+static void object_property_del_all(Object *obj)
+{
+ while (!QTAILQ_EMPTY(&obj->properties)) {
+ ObjectProperty *prop = QTAILQ_FIRST(&obj->properties);
+
+ QTAILQ_REMOVE(&obj->properties, prop, node);
+
+ if (prop->release) {
+ prop->release(obj, prop->name, prop->opaque);
+ }
+
+ g_free(prop->name);
+ g_free(prop->type);
+ g_free(prop);
+ }
+}
+
+static void object_property_del_child(Object *obj, Object *child, Error **errp)
+{
+ ObjectProperty *prop;
+
+ QTAILQ_FOREACH(prop, &obj->properties, node) {
+ if (object_property_is_child(prop) && prop->opaque == child) {
+ object_property_del(obj, prop->name, errp);
+ break;
+ }
+ }
+}
+
+void object_unparent(Object *obj)
+{
+ if (obj->parent) {
+ object_property_del_child(obj->parent, obj, NULL);
+ }
+}
+
static void object_deinit(Object *obj, TypeImpl *type)
{
if (type->instance_finalize) {
if (type_has_parent(type)) {
object_deinit(obj, type_get_parent(type));
}
+
+ object_unparent(obj);
}
void object_finalize(void *data)
TypeImpl *ti = obj->class->type;
object_deinit(obj, ti);
+ object_property_del_all(obj);
+
+ g_assert(obj->ref == 0);
}
Object *object_new_with_type(Type type)
Object *obj;
g_assert(type != NULL);
+ type_initialize(type);
obj = g_malloc(type->instance_size);
object_initialize_with_type(obj, type);
+ object_ref(obj);
return obj;
}
void object_delete(Object *obj)
{
- object_finalize(obj);
+ object_unref(obj);
+ g_assert(obj->ref == 0);
g_free(obj);
}
-static bool object_is_type(Object *obj, const char *typename)
+static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
{
- TypeImpl *target_type = type_get_by_name(typename);
- TypeImpl *type = obj->class->type;
- GSList *i;
+ assert(target_type);
/* Check if typename is a direct ancestor of type */
while (type) {
type = type_get_parent(type);
}
- /* Check if obj has an interface of typename */
- for (i = obj->interfaces; i; i = i->next) {
- Interface *iface = i->data;
-
- if (object_is_type(OBJECT(iface), typename)) {
- return true;
- }
- }
-
return false;
}
+static bool object_is_type(Object *obj, TypeImpl *target_type)
+{
+ return !target_type || type_is_ancestor(obj->class->type, target_type);
+}
+
Object *object_dynamic_cast(Object *obj, const char *typename)
{
+ TypeImpl *target_type = type_get_by_name(typename);
GSList *i;
- /* Check if typename is a direct ancestor */
- if (object_is_type(obj, typename)) {
+ /* Check if typename is a direct ancestor. Special-case TYPE_OBJECT,
+ * we want to go back from interfaces to the parent.
+ */
+ if (target_type && object_is_type(obj, target_type)) {
+ return obj;
+ }
+
+ /* Check if obj is an interface and its containing object is a direct
+ * ancestor of typename. In principle we could do this test at the very
+ * beginning of object_dynamic_cast, avoiding a second call to
+ * object_is_type. However, casting between interfaces is relatively
+ * rare, and object_is_type(obj, type_interface) would fail almost always.
+ *
+ * Perhaps we could add a magic value to the object header for increased
+ * (run-time) type safety and to speed up tests like this one. If we ever
+ * do that we can revisit the order here.
+ */
+ if (object_is_type(obj, type_interface)) {
+ assert(!obj->interfaces);
+ obj = INTERFACE(obj)->obj;
+ if (object_is_type(obj, target_type)) {
+ return obj;
+ }
+ }
+
+ if (!target_type) {
return obj;
}
for (i = obj->interfaces; i; i = i->next) {
Interface *iface = i->data;
- if (object_is_type(OBJECT(iface), typename)) {
+ if (object_is_type(OBJECT(iface), target_type)) {
return OBJECT(iface);
}
}
- /* Check if obj is an interface and its containing object is a direct
- * ancestor of typename */
- if (object_is_type(obj, TYPE_INTERFACE)) {
- Interface *iface = INTERFACE(obj);
-
- if (object_is_type(iface->obj, typename)) {
- return iface->obj;
- }
- }
-
return NULL;
}
-static void register_interface(void)
-{
- static TypeInfo interface_info = {
- .name = TYPE_INTERFACE,
- .instance_size = sizeof(Interface),
- .abstract = true,
- };
-
- type_register_static(&interface_info);
-}
-
-device_init(register_interface);
-
Object *object_dynamic_cast_assert(Object *obj, const char *typename)
{
Object *inst;
return NULL;
}
- type_class_init(type);
+ type_initialize(type);
+
+ return type->class;
+}
+
+ObjectClass *object_class_get_parent(ObjectClass *class)
+{
+ TypeImpl *type = type_get_parent(class->type);
+
+ if (!type) {
+ return NULL;
+ }
+
+ type_initialize(type);
return type->class;
}
TypeImpl *type = value;
ObjectClass *k;
- type_class_init(type);
+ type_initialize(type);
k = type->class;
if (!data->include_abstract && type->abstract) {
g_hash_table_foreach(type_table_get(), object_class_foreach_tramp, &data);
}
+
+int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
+ void *opaque)
+{
+ ObjectProperty *prop;
+ int ret = 0;
+
+ QTAILQ_FOREACH(prop, &obj->properties, node) {
+ if (object_property_is_child(prop)) {
+ ret = fn(prop->opaque, opaque);
+ if (ret != 0) {
+ break;
+ }
+ }
+ }
+ return ret;
+}
+
+static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
+{
+ GSList **list = opaque;
+
+ *list = g_slist_prepend(*list, klass);
+}
+
+GSList *object_class_get_list(const char *implements_type,
+ bool include_abstract)
+{
+ GSList *list = NULL;
+
+ object_class_foreach(object_class_get_list_tramp,
+ implements_type, include_abstract, &list);
+ return list;
+}
+
+void object_ref(Object *obj)
+{
+ obj->ref++;
+}
+
+void object_unref(Object *obj)
+{
+ g_assert(obj->ref > 0);
+ obj->ref--;
+
+ /* parent always holds a reference to its children */
+ if (obj->ref == 0) {
+ object_finalize(obj);
+ }
+}
+
+void object_property_add(Object *obj, const char *name, const char *type,
+ ObjectPropertyAccessor *get,
+ ObjectPropertyAccessor *set,
+ ObjectPropertyRelease *release,
+ void *opaque, Error **errp)
+{
+ ObjectProperty *prop = g_malloc0(sizeof(*prop));
+
+ prop->name = g_strdup(name);
+ prop->type = g_strdup(type);
+
+ prop->get = get;
+ prop->set = set;
+ prop->release = release;
+ prop->opaque = opaque;
+
+ QTAILQ_INSERT_TAIL(&obj->properties, prop, node);
+}
+
+static ObjectProperty *object_property_find(Object *obj, const char *name)
+{
+ ObjectProperty *prop;
+
+ QTAILQ_FOREACH(prop, &obj->properties, node) {
+ if (strcmp(prop->name, name) == 0) {
+ return prop;
+ }
+ }
+
+ return NULL;
+}
+
+void object_property_del(Object *obj, const char *name, Error **errp)
+{
+ ObjectProperty *prop = object_property_find(obj, name);
+
+ if (prop == NULL) {
+ error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
+ return;
+ }
+
+ if (prop->release) {
+ prop->release(obj, name, prop->opaque);
+ }
+
+ QTAILQ_REMOVE(&obj->properties, prop, node);
+
+ g_free(prop->name);
+ g_free(prop->type);
+ g_free(prop);
+}
+
+void object_property_get(Object *obj, Visitor *v, const char *name,
+ Error **errp)
+{
+ ObjectProperty *prop = object_property_find(obj, name);
+
+ if (prop == NULL) {
+ error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
+ return;
+ }
+
+ if (!prop->get) {
+ error_set(errp, QERR_PERMISSION_DENIED);
+ } else {
+ prop->get(obj, v, prop->opaque, name, errp);
+ }
+}
+
+void object_property_set(Object *obj, Visitor *v, const char *name,
+ Error **errp)
+{
+ ObjectProperty *prop = object_property_find(obj, name);
+
+ if (prop == NULL) {
+ error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
+ return;
+ }
+
+ if (!prop->set) {
+ error_set(errp, QERR_PERMISSION_DENIED);
+ } else {
+ prop->set(obj, v, prop->opaque, name, errp);
+ }
+}
+
+void object_property_set_str(Object *obj, const char *value,
+ const char *name, Error **errp)
+{
+ QString *qstr = qstring_from_str(value);
+ object_property_set_qobject(obj, QOBJECT(qstr), name, errp);
+
+ QDECREF(qstr);
+}
+
+char *object_property_get_str(Object *obj, const char *name,
+ Error **errp)
+{
+ QObject *ret = object_property_get_qobject(obj, name, errp);
+ QString *qstring;
+ char *retval;
+
+ if (!ret) {
+ return NULL;
+ }
+ qstring = qobject_to_qstring(ret);
+ if (!qstring) {
+ error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "string");
+ retval = NULL;
+ } else {
+ retval = g_strdup(qstring_get_str(qstring));
+ }
+
+ QDECREF(qstring);
+ return retval;
+}
+
+void object_property_set_link(Object *obj, Object *value,
+ const char *name, Error **errp)
+{
+ object_property_set_str(obj, object_get_canonical_path(value),
+ name, errp);
+}
+
+Object *object_property_get_link(Object *obj, const char *name,
+ Error **errp)
+{
+ char *str = object_property_get_str(obj, name, errp);
+ Object *target = NULL;
+
+ if (str && *str) {
+ target = object_resolve_path(str, NULL);
+ if (!target) {
+ error_set(errp, QERR_DEVICE_NOT_FOUND, str);
+ }
+ }
+
+ g_free(str);
+ return target;
+}
+
+void object_property_set_bool(Object *obj, bool value,
+ const char *name, Error **errp)
+{
+ QBool *qbool = qbool_from_int(value);
+ object_property_set_qobject(obj, QOBJECT(qbool), name, errp);
+
+ QDECREF(qbool);
+}
+
+bool object_property_get_bool(Object *obj, const char *name,
+ Error **errp)
+{
+ QObject *ret = object_property_get_qobject(obj, name, errp);
+ QBool *qbool;
+ bool retval;
+
+ if (!ret) {
+ return false;
+ }
+ qbool = qobject_to_qbool(ret);
+ if (!qbool) {
+ error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "boolean");
+ retval = false;
+ } else {
+ retval = qbool_get_int(qbool);
+ }
+
+ QDECREF(qbool);
+ return retval;
+}
+
+void object_property_set_int(Object *obj, int64_t value,
+ const char *name, Error **errp)
+{
+ QInt *qint = qint_from_int(value);
+ object_property_set_qobject(obj, QOBJECT(qint), name, errp);
+
+ QDECREF(qint);
+}
+
+int64_t object_property_get_int(Object *obj, const char *name,
+ Error **errp)
+{
+ QObject *ret = object_property_get_qobject(obj, name, errp);
+ QInt *qint;
+ int64_t retval;
+
+ if (!ret) {
+ return -1;
+ }
+ qint = qobject_to_qint(ret);
+ if (!qint) {
+ error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "int");
+ retval = -1;
+ } else {
+ retval = qint_get_int(qint);
+ }
+
+ QDECREF(qint);
+ return retval;
+}
+
+void object_property_parse(Object *obj, const char *string,
+ const char *name, Error **errp)
+{
+ StringInputVisitor *mi;
+ mi = string_input_visitor_new(string);
+ object_property_set(obj, string_input_get_visitor(mi), name, errp);
+
+ string_input_visitor_cleanup(mi);
+}
+
+char *object_property_print(Object *obj, const char *name,
+ Error **errp)
+{
+ StringOutputVisitor *mo;
+ char *string;
+
+ mo = string_output_visitor_new();
+ object_property_get(obj, string_output_get_visitor(mo), name, errp);
+ string = string_output_get_string(mo);
+ string_output_visitor_cleanup(mo);
+ return string;
+}
+
+const char *object_property_get_type(Object *obj, const char *name, Error **errp)
+{
+ ObjectProperty *prop = object_property_find(obj, name);
+
+ if (prop == NULL) {
+ error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
+ return NULL;
+ }
+
+ return prop->type;
+}
+
+Object *object_get_root(void)
+{
+ static Object *root;
+
+ if (!root) {
+ root = object_new("container");
+ }
+
+ return root;
+}
+
+static void object_get_child_property(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ Object *child = opaque;
+ gchar *path;
+
+ path = object_get_canonical_path(child);
+ visit_type_str(v, &path, name, errp);
+ g_free(path);
+}
+
+static void object_finalize_child_property(Object *obj, const char *name,
+ void *opaque)
+{
+ Object *child = opaque;
+
+ object_unref(child);
+}
+
+void object_property_add_child(Object *obj, const char *name,
+ Object *child, Error **errp)
+{
+ gchar *type;
+
+ /* Registering an interface object in the composition tree will mightily
+ * confuse object_get_canonical_path (which, on the other hand, knows how
+ * to get the canonical path of an interface object).
+ */
+ assert(!object_is_type(obj, type_interface));
+
+ type = g_strdup_printf("child<%s>", object_get_typename(OBJECT(child)));
+
+ object_property_add(obj, name, type, object_get_child_property,
+ NULL, object_finalize_child_property, child, errp);
+
+ object_ref(child);
+ g_assert(child->parent == NULL);
+ child->parent = obj;
+
+ g_free(type);
+}
+
+static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ Object **child = opaque;
+ gchar *path;
+
+ if (*child) {
+ path = object_get_canonical_path(*child);
+ visit_type_str(v, &path, name, errp);
+ g_free(path);
+ } else {
+ path = (gchar *)"";
+ visit_type_str(v, &path, name, errp);
+ }
+}
+
+static void object_set_link_property(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ Object **child = opaque;
+ Object *old_target;
+ bool ambiguous = false;
+ const char *type;
+ char *path;
+ gchar *target_type;
+
+ type = object_property_get_type(obj, name, NULL);
+
+ visit_type_str(v, &path, name, errp);
+
+ old_target = *child;
+ *child = NULL;
+
+ if (strcmp(path, "") != 0) {
+ Object *target;
+
+ /* Go from link<FOO> to FOO. */
+ target_type = g_strndup(&type[5], strlen(type) - 6);
+ target = object_resolve_path_type(path, target_type, &ambiguous);
+
+ if (ambiguous) {
+ error_set(errp, QERR_AMBIGUOUS_PATH, path);
+ } else if (target) {
+ object_ref(target);
+ *child = target;
+ } else {
+ target = object_resolve_path(path, &ambiguous);
+ if (target || ambiguous) {
+ error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
+ } else {
+ error_set(errp, QERR_DEVICE_NOT_FOUND, path);
+ }
+ }
+ g_free(target_type);
+ }
+
+ g_free(path);
+
+ if (old_target != NULL) {
+ object_unref(old_target);
+ }
+}
+
+void object_property_add_link(Object *obj, const char *name,
+ const char *type, Object **child,
+ Error **errp)
+{
+ gchar *full_type;
+
+ full_type = g_strdup_printf("link<%s>", type);
+
+ object_property_add(obj, name, full_type,
+ object_get_link_property,
+ object_set_link_property,
+ NULL, child, errp);
+
+ g_free(full_type);
+}
+
+gchar *object_get_canonical_path(Object *obj)
+{
+ Object *root = object_get_root();
+ char *newpath = NULL, *path = NULL;
+
+ if (object_is_type(obj, type_interface)) {
+ obj = INTERFACE(obj)->obj;
+ }
+
+ while (obj != root) {
+ ObjectProperty *prop = NULL;
+
+ g_assert(obj->parent != NULL);
+
+ QTAILQ_FOREACH(prop, &obj->parent->properties, node) {
+ if (!object_property_is_child(prop)) {
+ continue;
+ }
+
+ if (prop->opaque == obj) {
+ if (path) {
+ newpath = g_strdup_printf("%s/%s", prop->name, path);
+ g_free(path);
+ path = newpath;
+ } else {
+ path = g_strdup(prop->name);
+ }
+ break;
+ }
+ }
+
+ g_assert(prop != NULL);
+
+ obj = obj->parent;
+ }
+
+ newpath = g_strdup_printf("/%s", path);
+ g_free(path);
+
+ return newpath;
+}
+
+Object *object_resolve_path_component(Object *parent, gchar *part)
+{
+ ObjectProperty *prop = object_property_find(parent, part);
+ if (prop == NULL) {
+ return NULL;
+ }
+
+ if (object_property_is_link(prop)) {
+ return *(Object **)prop->opaque;
+ } else if (object_property_is_child(prop)) {
+ return prop->opaque;
+ } else {
+ return NULL;
+ }
+}
+
+static Object *object_resolve_abs_path(Object *parent,
+ gchar **parts,
+ const char *typename,
+ int index)
+{
+ Object *child;
+
+ if (parts[index] == NULL) {
+ return object_dynamic_cast(parent, typename);
+ }
+
+ if (strcmp(parts[index], "") == 0) {
+ return object_resolve_abs_path(parent, parts, typename, index + 1);
+ }
+
+ child = object_resolve_path_component(parent, parts[index]);
+ if (!child) {
+ return NULL;
+ }
+
+ return object_resolve_abs_path(child, parts, typename, index + 1);
+}
+
+static Object *object_resolve_partial_path(Object *parent,
+ gchar **parts,
+ const char *typename,
+ bool *ambiguous)
+{
+ Object *obj;
+ ObjectProperty *prop;
+
+ obj = object_resolve_abs_path(parent, parts, typename, 0);
+
+ QTAILQ_FOREACH(prop, &parent->properties, node) {
+ Object *found;
+
+ if (!object_property_is_child(prop)) {
+ continue;
+ }
+
+ found = object_resolve_partial_path(prop->opaque, parts,
+ typename, ambiguous);
+ if (found) {
+ if (obj) {
+ if (ambiguous) {
+ *ambiguous = true;
+ }
+ return NULL;
+ }
+ obj = found;
+ }
+
+ if (ambiguous && *ambiguous) {
+ return NULL;
+ }
+ }
+
+ return obj;
+}
+
+Object *object_resolve_path_type(const char *path, const char *typename,
+ bool *ambiguous)
+{
+ bool partial_path = true;
+ Object *obj;
+ gchar **parts;
+
+ parts = g_strsplit(path, "/", 0);
+ if (parts == NULL || parts[0] == NULL) {
+ g_strfreev(parts);
+ return object_get_root();
+ }
+
+ if (strcmp(parts[0], "") == 0) {
+ partial_path = false;
+ }
+
+ if (partial_path) {
+ if (ambiguous) {
+ *ambiguous = false;
+ }
+ obj = object_resolve_partial_path(object_get_root(), parts,
+ typename, ambiguous);
+ } else {
+ obj = object_resolve_abs_path(object_get_root(), parts, typename, 1);
+ }
+
+ g_strfreev(parts);
+
+ return obj;
+}
+
+Object *object_resolve_path(const char *path, bool *ambiguous)
+{
+ return object_resolve_path_type(path, TYPE_OBJECT, ambiguous);
+}
+
+typedef struct StringProperty
+{
+ char *(*get)(Object *, Error **);
+ void (*set)(Object *, const char *, Error **);
+} StringProperty;
+
+static void property_get_str(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ StringProperty *prop = opaque;
+ char *value;
+
+ value = prop->get(obj, errp);
+ if (value) {
+ visit_type_str(v, &value, name, errp);
+ g_free(value);
+ }
+}
+
+static void property_set_str(Object *obj, Visitor *v, void *opaque,
+ const char *name, Error **errp)
+{
+ StringProperty *prop = opaque;
+ char *value;
+ Error *local_err = NULL;
+
+ visit_type_str(v, &value, name, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ prop->set(obj, value, errp);
+ g_free(value);
+}
+
+static void property_release_str(Object *obj, const char *name,
+ void *opaque)
+{
+ StringProperty *prop = opaque;
+ g_free(prop);
+}
+
+void object_property_add_str(Object *obj, const char *name,
+ char *(*get)(Object *, Error **),
+ void (*set)(Object *, const char *, Error **),
+ Error **errp)
+{
+ StringProperty *prop = g_malloc0(sizeof(*prop));
+
+ prop->get = get;
+ prop->set = set;
+
+ object_property_add(obj, name, "string",
+ get ? property_get_str : NULL,
+ set ? property_set_str : NULL,
+ property_release_str,
+ prop, errp);
+}
+
+static char *qdev_get_type(Object *obj, Error **errp)
+{
+ return g_strdup(object_get_typename(obj));
+}
+
+static void object_instance_init(Object *obj)
+{
+ object_property_add_str(obj, "type", qdev_get_type, NULL, NULL);
+}
+
+static void register_types(void)
+{
+ static TypeInfo interface_info = {
+ .name = TYPE_INTERFACE,
+ .instance_size = sizeof(Interface),
+ .abstract = true,
+ };
+
+ static TypeInfo object_info = {
+ .name = TYPE_OBJECT,
+ .instance_size = sizeof(Object),
+ .instance_init = object_instance_init,
+ .abstract = true,
+ };
+
+ type_interface = type_register_internal(&interface_info);
+ type_register_internal(&object_info);
+}
+
+type_init(register_types)