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+/*
+ * QEMU Object Model
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef QEMU_OBJECT_H
+#define QEMU_OBJECT_H
+
+#include <glib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include "qemu/queue.h"
+#include "qapi/error.h"
+
+#define Type QEMUType
+#define class QEMUclass
+#define typename QEMUtypename
+
+struct Visitor;
+
+struct TypeImpl;
+typedef struct TypeImpl *Type;
+
+typedef struct ObjectClass ObjectClass;
+typedef struct Object Object;
+
+typedef struct TypeInfo TypeInfo;
+
+typedef struct InterfaceClass InterfaceClass;
+typedef struct InterfaceInfo InterfaceInfo;
+
+#define TYPE_OBJECT "object"
+
+/**
+ * SECTION:object.h
+ * @title:Base Object Type System
+ * @short_description: interfaces for creating new types and objects
+ *
+ * The QEMU Object Model provides a framework for registering user creatable
+ * types and instantiating objects from those types. QOM provides the following
+ * features:
+ *
+ * - System for dynamically registering types
+ * - Support for single-inheritance of types
+ * - Multiple inheritance of stateless interfaces
+ *
+ * <example>
+ * <title>Creating a minimal type</title>
+ * <programlisting>
+ * #include "qdev.h"
+ *
+ * #define TYPE_MY_DEVICE "my-device"
+ *
+ * // No new virtual functions: we can reuse the typedef for the
+ * // superclass.
+ * typedef DeviceClass MyDeviceClass;
+ * typedef struct MyDevice
+ * {
+ * DeviceState parent;
+ *
+ * int reg0, reg1, reg2;
+ * } MyDevice;
+ *
+ * static const TypeInfo my_device_info = {
+ * .name = TYPE_MY_DEVICE,
+ * .parent = TYPE_DEVICE,
+ * .instance_size = sizeof(MyDevice),
+ * };
+ *
+ * static void my_device_register_types(void)
+ * {
+ * type_register_static(&my_device_info);
+ * }
+ *
+ * type_init(my_device_register_types)
+ * </programlisting>
+ * </example>
+ *
+ * In the above example, we create a simple type that is described by #TypeInfo.
+ * #TypeInfo describes information about the type including what it inherits
+ * from, the instance and class size, and constructor/destructor hooks.
+ *
+ * Every type has an #ObjectClass associated with it. #ObjectClass derivatives
+ * are instantiated dynamically but there is only ever one instance for any
+ * given type. The #ObjectClass typically holds a table of function pointers
+ * for the virtual methods implemented by this type.
+ *
+ * Using object_new(), a new #Object derivative will be instantiated. You can
+ * cast an #Object to a subclass (or base-class) type using
+ * object_dynamic_cast(). You typically want to define macro wrappers around
+ * OBJECT_CHECK() and OBJECT_CLASS_CHECK() to make it easier to convert to a
+ * specific type:
+ *
+ * <example>
+ * <title>Typecasting macros</title>
+ * <programlisting>
+ * #define MY_DEVICE_GET_CLASS(obj) \
+ * OBJECT_GET_CLASS(MyDeviceClass, obj, TYPE_MY_DEVICE)
+ * #define MY_DEVICE_CLASS(klass) \
+ * OBJECT_CLASS_CHECK(MyDeviceClass, klass, TYPE_MY_DEVICE)
+ * #define MY_DEVICE(obj) \
+ * OBJECT_CHECK(MyDevice, obj, TYPE_MY_DEVICE)
+ * </programlisting>
+ * </example>
+ *
+ * # Class Initialization #
+ *
+ * Before an object is initialized, the class for the object must be
+ * initialized. There is only one class object for all instance objects
+ * that is created lazily.
+ *
+ * Classes are initialized by first initializing any parent classes (if
+ * necessary). After the parent class object has initialized, it will be
+ * copied into the current class object and any additional storage in the
+ * class object is zero filled.
+ *
+ * The effect of this is that classes automatically inherit any virtual
+ * function pointers that the parent class has already initialized. All
+ * other fields will be zero filled.
+ *
+ * Once all of the parent classes have been initialized, #TypeInfo::class_init
+ * is called to let the class being instantiated provide default initialize for
+ * its virtual functions. Here is how the above example might be modified
+ * to introduce an overridden virtual function:
+ *
+ * <example>
+ * <title>Overriding a virtual function</title>
+ * <programlisting>
+ * #include "qdev.h"
+ *
+ * void my_device_class_init(ObjectClass *klass, void *class_data)
+ * {
+ * DeviceClass *dc = DEVICE_CLASS(klass);
+ * dc->reset = my_device_reset;
+ * }
+ *
+ * static const TypeInfo my_device_info = {
+ * .name = TYPE_MY_DEVICE,
+ * .parent = TYPE_DEVICE,
+ * .instance_size = sizeof(MyDevice),
+ * .class_init = my_device_class_init,
+ * };
+ * </programlisting>
+ * </example>
+ *
+ * Introducing new virtual methods requires a class to define its own
+ * struct and to add a .class_size member to the #TypeInfo. Each method
+ * will also have a wrapper function to call it easily:
+ *
+ * <example>
+ * <title>Defining an abstract class</title>
+ * <programlisting>
+ * #include "qdev.h"
+ *
+ * typedef struct MyDeviceClass
+ * {
+ * DeviceClass parent;
+ *
+ * void (*frobnicate) (MyDevice *obj);
+ * } MyDeviceClass;
+ *
+ * static const TypeInfo my_device_info = {
+ * .name = TYPE_MY_DEVICE,
+ * .parent = TYPE_DEVICE,
+ * .instance_size = sizeof(MyDevice),
+ * .abstract = true, // or set a default in my_device_class_init
+ * .class_size = sizeof(MyDeviceClass),
+ * };
+ *
+ * void my_device_frobnicate(MyDevice *obj)
+ * {
+ * MyDeviceClass *klass = MY_DEVICE_GET_CLASS(obj);
+ *
+ * klass->frobnicate(obj);
+ * }
+ * </programlisting>
+ * </example>
+ *
+ * # Interfaces #
+ *
+ * Interfaces allow a limited form of multiple inheritance. Instances are
+ * similar to normal types except for the fact that are only defined by
+ * their classes and never carry any state. You can dynamically cast an object
+ * to one of its #Interface types and vice versa.
+ *
+ * # Methods #
+ *
+ * A <emphasis>method</emphasis> is a function within the namespace scope of
+ * a class. It usually operates on the object instance by passing it as a
+ * strongly-typed first argument.
+ * If it does not operate on an object instance, it is dubbed
+ * <emphasis>class method</emphasis>.
+ *
+ * Methods cannot be overloaded. That is, the #ObjectClass and method name
+ * uniquely identity the function to be called; the signature does not vary
+ * except for trailing varargs.
+ *
+ * Methods are always <emphasis>virtual</emphasis>. Overriding a method in
+ * #TypeInfo.class_init of a subclass leads to any user of the class obtained
+ * via OBJECT_GET_CLASS() accessing the overridden function.
+ * The original function is not automatically invoked. It is the responsibility
+ * of the overriding class to determine whether and when to invoke the method
+ * being overridden.
+ *
+ * To invoke the method being overridden, the preferred solution is to store
+ * the original value in the overriding class before overriding the method.
+ * This corresponds to |[ {super,base}.method(...) ]| in Java and C#
+ * respectively; this frees the overriding class from hardcoding its parent
+ * class, which someone might choose to change at some point.
+ *
+ * <example>
+ * <title>Overriding a virtual method</title>
+ * <programlisting>
+ * typedef struct MyState MyState;
+ *
+ * typedef void (*MyDoSomething)(MyState *obj);
+ *
+ * typedef struct MyClass {
+ * ObjectClass parent_class;
+ *
+ * MyDoSomething do_something;
+ * } MyClass;
+ *
+ * static void my_do_something(MyState *obj)
+ * {
+ * // do something
+ * }
+ *
+ * static void my_class_init(ObjectClass *oc, void *data)
+ * {
+ * MyClass *mc = MY_CLASS(oc);
+ *
+ * mc->do_something = my_do_something;
+ * }
+ *
+ * static const TypeInfo my_type_info = {
+ * .name = TYPE_MY,
+ * .parent = TYPE_OBJECT,
+ * .instance_size = sizeof(MyState),
+ * .class_size = sizeof(MyClass),
+ * .class_init = my_class_init,
+ * };
+ *
+ * typedef struct DerivedClass {
+ * MyClass parent_class;
+ *
+ * MyDoSomething parent_do_something;
+ * } DerivedClass;
+ *
+ * static void derived_do_something(MyState *obj)
+ * {
+ * DerivedClass *dc = DERIVED_GET_CLASS(obj);
+ *
+ * // do something here
+ * dc->parent_do_something(obj);
+ * // do something else here
+ * }
+ *
+ * static void derived_class_init(ObjectClass *oc, void *data)
+ * {
+ * MyClass *mc = MY_CLASS(oc);
+ * DerivedClass *dc = DERIVED_CLASS(oc);
+ *
+ * dc->parent_do_something = mc->do_something;
+ * mc->do_something = derived_do_something;
+ * }
+ *
+ * static const TypeInfo derived_type_info = {
+ * .name = TYPE_DERIVED,
+ * .parent = TYPE_MY,
+ * .class_size = sizeof(DerivedClass),
+ * .class_init = derived_class_init,
+ * };
+ * </programlisting>
+ * </example>
+ *
+ * Alternatively, object_class_by_name() can be used to obtain the class and
+ * its non-overridden methods for a specific type. This would correspond to
+ * |[ MyClass::method(...) ]| in C++.
+ *
+ * The first example of such a QOM method was #CPUClass.reset,
+ * another example is #DeviceClass.realize.
+ */
+
+
+/**
+ * ObjectPropertyAccessor:
+ * @obj: the object that owns the property
+ * @v: the visitor that contains the property data
+ * @opaque: the object property opaque
+ * @name: the name of the property
+ * @errp: a pointer to an Error that is filled if getting/setting fails.
+ *
+ * Called when trying to get/set a property.
+ */
+typedef void (ObjectPropertyAccessor)(Object *obj,
+ struct Visitor *v,
+ void *opaque,
+ const char *name,
+ Error **errp);
+
+/**
+ * ObjectPropertyResolve:
+ * @obj: the object that owns the property
+ * @opaque: the opaque registered with the property
+ * @part: the name of the property
+ *
+ * Resolves the #Object corresponding to property @part.
+ *
+ * The returned object can also be used as a starting point
+ * to resolve a relative path starting with "@part".
+ *
+ * Returns: If @path is the path that led to @obj, the function
+ * returns the #Object corresponding to "@path/@part".
+ * If "@path/@part" is not a valid object path, it returns #NULL.
+ */
+typedef Object *(ObjectPropertyResolve)(Object *obj,
+ void *opaque,
+ const char *part);
+
+/**
+ * ObjectPropertyRelease:
+ * @obj: the object that owns the property
+ * @name: the name of the property
+ * @opaque: the opaque registered with the property
+ *
+ * Called when a property is removed from a object.
+ */
+typedef void (ObjectPropertyRelease)(Object *obj,
+ const char *name,
+ void *opaque);
+
+typedef struct ObjectProperty
+{
+ gchar *name;
+ gchar *type;
+ gchar *description;
+ ObjectPropertyAccessor *get;
+ ObjectPropertyAccessor *set;
+ ObjectPropertyResolve *resolve;
+ ObjectPropertyRelease *release;
+ void *opaque;
+} ObjectProperty;
+
+/**
+ * ObjectUnparent:
+ * @obj: the object that is being removed from the composition tree
+ *
+ * Called when an object is being removed from the QOM composition tree.
+ * The function should remove any backlinks from children objects to @obj.
+ */
+typedef void (ObjectUnparent)(Object *obj);
+
+/**
+ * ObjectFree:
+ * @obj: the object being freed
+ *
+ * Called when an object's last reference is removed.
+ */
+typedef void (ObjectFree)(void *obj);
+
+#define OBJECT_CLASS_CAST_CACHE 4
+
+/**
+ * ObjectClass:
+ *
+ * The base for all classes. The only thing that #ObjectClass contains is an
+ * integer type handle.
+ */
+struct ObjectClass
+{
+ /*< private >*/
+ Type type;
+ GSList *interfaces;
+
+ const char *object_cast_cache[OBJECT_CLASS_CAST_CACHE];
+ const char *class_cast_cache[OBJECT_CLASS_CAST_CACHE];
+
+ ObjectUnparent *unparent;
+};
+
+/**
+ * Object:
+ *
+ * The base for all objects. The first member of this object is a pointer to
+ * a #ObjectClass. Since C guarantees that the first member of a structure
+ * always begins at byte 0 of that structure, as long as any sub-object places
+ * its parent as the first member, we can cast directly to a #Object.
+ *
+ * As a result, #Object contains a reference to the objects type as its
+ * first member. This allows identification of the real type of the object at
+ * run time.
+ */
+struct Object
+{
+ /*< private >*/
+ ObjectClass *class;
+ ObjectFree *free;
+ GHashTable *properties;
+ uint32_t ref;
+ Object *parent;
+};
+
+/**
+ * TypeInfo:
+ * @name: The name of the type.
+ * @parent: The name of the parent type.
+ * @instance_size: The size of the object (derivative of #Object). If
+ * @instance_size is 0, then the size of the object will be the size of the
+ * parent object.
+ * @instance_init: This function is called to initialize an object. The parent
+ * class will have already been initialized so the type is only responsible
+ * for initializing its own members.
+ * @instance_post_init: This function is called to finish initialization of
+ * an object, after all @instance_init functions were called.
+ * @instance_finalize: This function is called during object destruction. This
+ * is called before the parent @instance_finalize function has been called.
+ * An object should only free the members that are unique to its type in this
+ * function.
+ * @abstract: If this field is true, then the class is considered abstract and
+ * cannot be directly instantiated.
+ * @class_size: The size of the class object (derivative of #ObjectClass)
+ * for this object. If @class_size is 0, then the size of the class will be
+ * assumed to be the size of the parent class. This allows a type to avoid
+ * implementing an explicit class type if they are not adding additional
+ * virtual functions.
+ * @class_init: This function is called after all parent class initialization
+ * has occurred to allow a class to set its default virtual method pointers.
+ * This is also the function to use to override virtual methods from a parent
+ * class.
+ * @class_base_init: This function is called for all base classes after all
+ * parent class initialization has occurred, but before the class itself
+ * is initialized. This is the function to use to undo the effects of
+ * memcpy from the parent class to the descendents.
+ * @class_finalize: This function is called during class destruction and is
+ * meant to release and dynamic parameters allocated by @class_init.
+ * @class_data: Data to pass to the @class_init, @class_base_init and
+ * @class_finalize functions. This can be useful when building dynamic
+ * classes.
+ * @interfaces: The list of interfaces associated with this type. This
+ * should point to a static array that's terminated with a zero filled
+ * element.
+ */
+struct TypeInfo
+{
+ const char *name;
+ const char *parent;
+
+ size_t instance_size;
+ void (*instance_init)(Object *obj);
+ void (*instance_post_init)(Object *obj);
+ void (*instance_finalize)(Object *obj);
+
+ bool abstract;
+ size_t class_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;
+
+ InterfaceInfo *interfaces;
+};
+
+/**
+ * OBJECT:
+ * @obj: A derivative of #Object
+ *
+ * Converts an object to a #Object. Since all objects are #Objects,
+ * this function will always succeed.
+ */
+#define OBJECT(obj) \
+ ((Object *)(obj))
+
+/**
+ * OBJECT_CLASS:
+ * @class: A derivative of #ObjectClass.
+ *
+ * Converts a class to an #ObjectClass. Since all objects are #Objects,
+ * this function will always succeed.
+ */
+#define OBJECT_CLASS(class) \
+ ((ObjectClass *)(class))
+
+/**
+ * OBJECT_CHECK:
+ * @type: The C type to use for the return value.
+ * @obj: A derivative of @type to cast.
+ * @name: The QOM typename of @type
+ *
+ * A type safe version of @object_dynamic_cast_assert. Typically each class
+ * will define a macro based on this type to perform type safe dynamic_casts to
+ * this object type.
+ *
+ * If an invalid object is passed to this function, a run time assert will be
+ * generated.
+ */
+#define OBJECT_CHECK(type, obj, name) \
+ ((type *)object_dynamic_cast_assert(OBJECT(obj), (name), \
+ __FILE__, __LINE__, __func__))
+
+/**
+ * OBJECT_CLASS_CHECK:
+ * @class_type: The C type to use for the return value.
+ * @class: A derivative class of @class_type to cast.
+ * @name: the QOM typename of @class_type.
+ *
+ * A type safe version of @object_class_dynamic_cast_assert. This macro is
+ * typically wrapped by each type to perform type safe casts of a class to a
+ * specific class type.
+ */
+#define OBJECT_CLASS_CHECK(class_type, class, name) \
+ ((class_type *)object_class_dynamic_cast_assert(OBJECT_CLASS(class), (name), \
+ __FILE__, __LINE__, __func__))
+
+/**
+ * OBJECT_GET_CLASS:
+ * @class: The C type to use for the return value.
+ * @obj: The object to obtain the class for.
+ * @name: The QOM typename of @obj.
+ *
+ * This function will return a specific class for a given object. Its generally
+ * used by each type to provide a type safe macro to get a specific class type
+ * from an object.
+ */
+#define OBJECT_GET_CLASS(class, obj, name) \
+ OBJECT_CLASS_CHECK(class, object_get_class(OBJECT(obj)), name)
+
+/**
+ * InterfaceInfo:
+ * @type: The name of the interface.
+ *
+ * The information associated with an interface.
+ */
+struct InterfaceInfo {
+ const char *type;
+};
+
+/**
+ * InterfaceClass:
+ * @parent_class: the base class
+ *
+ * The class for all interfaces. Subclasses of this class should only add
+ * virtual methods.
+ */
+struct InterfaceClass
+{
+ ObjectClass parent_class;
+ /*< private >*/
+ ObjectClass *concrete_class;
+ Type interface_type;
+};
+
+#define TYPE_INTERFACE "interface"
+
+/**
+ * INTERFACE_CLASS:
+ * @klass: class to cast from
+ * Returns: An #InterfaceClass or raise an error if cast is invalid
+ */
+#define INTERFACE_CLASS(klass) \
+ OBJECT_CLASS_CHECK(InterfaceClass, klass, TYPE_INTERFACE)
+
+/**
+ * INTERFACE_CHECK:
+ * @interface: the type to return
+ * @obj: the object to convert to an interface
+ * @name: the interface type name
+ *
+ * Returns: @obj casted to @interface if cast is valid, otherwise raise error.
+ */
+#define INTERFACE_CHECK(interface, obj, name) \
+ ((interface *)object_dynamic_cast_assert(OBJECT((obj)), (name), \
+ __FILE__, __LINE__, __func__))
+
+/**
+ * object_new:
+ * @typename: The name of the type of the object to instantiate.
+ *
+ * This function will initialize a new object using heap allocated memory.
+ * The returned object has a reference count of 1, and will be freed when
+ * the last reference is dropped.
+ *
+ * Returns: The newly allocated and instantiated object.
+ */
+Object *object_new(const char *typename);
+
+/**
+ * object_new_with_type:
+ * @type: The type of the object to instantiate.
+ *
+ * This function will initialize a new object using heap allocated memory.
+ * The returned object has a reference count of 1, and will be freed when
+ * the last reference is dropped.
+ *
+ * Returns: The newly allocated and instantiated object.
+ */
+Object *object_new_with_type(Type type);
+
+/**
+ * object_new_with_props:
+ * @typename: The name of the type of the object to instantiate.
+ * @parent: the parent object
+ * @id: The unique ID of the object
+ * @errp: pointer to error object
+ * @...: list of property names and values
+ *
+ * This function will initialize a new object using heap allocated memory.
+ * The returned object has a reference count of 1, and will be freed when
+ * the last reference is dropped.
+ *
+ * The @id parameter will be used when registering the object as a
+ * child of @parent in the composition tree.
+ *
+ * The variadic parameters are a list of pairs of (propname, propvalue)
+ * strings. The propname of %NULL indicates the end of the property
+ * list. If the object implements the user creatable interface, the
+ * object will be marked complete once all the properties have been
+ * processed.
+ *
+ * <example>
+ * <title>Creating an object with properties</title>
+ * <programlisting>
+ * Error *err = NULL;
+ * Object *obj;
+ *
+ * obj = object_new_with_props(TYPE_MEMORY_BACKEND_FILE,
+ * object_get_objects_root(),
+ * "hostmem0",
+ * &err,
+ * "share", "yes",
+ * "mem-path", "/dev/shm/somefile",
+ * "prealloc", "yes",
+ * "size", "1048576",
+ * NULL);
+ *
+ * if (!obj) {
+ * g_printerr("Cannot create memory backend: %s\n",
+ * error_get_pretty(err));
+ * }
+ * </programlisting>
+ * </example>
+ *
+ * The returned object will have one stable reference maintained
+ * for as long as it is present in the object hierarchy.
+ *
+ * Returns: The newly allocated, instantiated & initialized object.
+ */
+Object *object_new_with_props(const char *typename,
+ Object *parent,
+ const char *id,
+ Error **errp,
+ ...) QEMU_SENTINEL;
+
+/**
+ * object_new_with_propv:
+ * @typename: The name of the type of the object to instantiate.
+ * @parent: the parent object
+ * @id: The unique ID of the object
+ * @errp: pointer to error object
+ * @vargs: list of property names and values
+ *
+ * See object_new_with_props() for documentation.
+ */
+Object *object_new_with_propv(const char *typename,
+ Object *parent,
+ const char *id,
+ Error **errp,
+ va_list vargs);
+
+/**
+ * object_set_props:
+ * @obj: the object instance to set properties on
+ * @errp: pointer to error object
+ * @...: list of property names and values
+ *
+ * This function will set a list of properties on an existing object
+ * instance.
+ *
+ * The variadic parameters are a list of pairs of (propname, propvalue)
+ * strings. The propname of %NULL indicates the end of the property
+ * list.
+ *
+ * <example>
+ * <title>Update an object's properties</title>
+ * <programlisting>
+ * Error *err = NULL;
+ * Object *obj = ...get / create object...;
+ *
+ * obj = object_set_props(obj,
+ * &err,
+ * "share", "yes",
+ * "mem-path", "/dev/shm/somefile",
+ * "prealloc", "yes",
+ * "size", "1048576",
+ * NULL);
+ *
+ * if (!obj) {
+ * g_printerr("Cannot set properties: %s\n",
+ * error_get_pretty(err));
+ * }
+ * </programlisting>
+ * </example>
+ *
+ * The returned object will have one stable reference maintained
+ * for as long as it is present in the object hierarchy.
+ *
+ * Returns: -1 on error, 0 on success
+ */
+int object_set_props(Object *obj,
+ Error **errp,
+ ...) QEMU_SENTINEL;
+
+/**
+ * object_set_propv:
+ * @obj: the object instance to set properties on
+ * @errp: pointer to error object
+ * @vargs: list of property names and values
+ *
+ * See object_set_props() for documentation.
+ *
+ * Returns: -1 on error, 0 on success
+ */
+int object_set_propv(Object *obj,
+ Error **errp,
+ va_list vargs);
+
+/**
+ * object_initialize_with_type:
+ * @data: A pointer to the memory to be used for the object.
+ * @size: The maximum size available at @data for the object.
+ * @type: The type of the object to instantiate.
+ *
+ * This function will initialize an object. The memory for the object should
+ * have already been allocated. The returned object has a reference count of 1,
+ * and will be finalized when the last reference is dropped.
+ */
+void object_initialize_with_type(void *data, size_t size, Type type);
+
+/**
+ * object_initialize:
+ * @obj: A pointer to the memory to be used for the object.
+ * @size: The maximum size available at @obj for the object.
+ * @typename: The name of the type of the object to instantiate.
+ *
+ * This function will initialize an object. The memory for the object should
+ * have already been allocated. The returned object has a reference count of 1,
+ * and will be finalized when the last reference is dropped.
+ */
+void object_initialize(void *obj, size_t size, const char *typename);
+
+/**
+ * object_dynamic_cast:
+ * @obj: The object to cast.
+ * @typename: The @typename to cast to.
+ *
+ * This function will determine if @obj is-a @typename. @obj can refer to an
+ * object or an interface associated with an object.
+ *
+ * Returns: This function returns @obj on success or #NULL on failure.
+ */
+Object *object_dynamic_cast(Object *obj, const char *typename);
+
+/**
+ * object_dynamic_cast_assert:
+ *
+ * See object_dynamic_cast() for a description of the parameters of this
+ * function. The only difference in behavior is that this function asserts
+ * instead of returning #NULL on failure if QOM cast debugging is enabled.
+ * This function is not meant to be called directly, but only through
+ * the wrapper macro OBJECT_CHECK.
+ */
+Object *object_dynamic_cast_assert(Object *obj, const char *typename,
+ const char *file, int line, const char *func);
+
+/**
+ * object_get_class:
+ * @obj: A derivative of #Object
+ *
+ * Returns: The #ObjectClass of the type associated with @obj.
+ */
+ObjectClass *object_get_class(Object *obj);
+
+/**
+ * object_get_typename:
+ * @obj: A derivative of #Object.
+ *
+ * Returns: The QOM typename of @obj.
+ */
+const char *object_get_typename(Object *obj);
+
+/**
+ * type_register_static:
+ * @info: The #TypeInfo of the new type.
+ *
+ * @info and all of the strings it points to should exist for the life time
+ * that the type is registered.
+ *
+ * Returns: 0 on failure, the new #Type on success.
+ */
+Type type_register_static(const TypeInfo *info);
+
+/**
+ * type_register:
+ * @info: The #TypeInfo of the new type
+ *
+ * Unlike type_register_static(), this call does not require @info or its
+ * string members to continue to exist after the call returns.
+ *
+ * Returns: 0 on failure, the new #Type on success.
+ */
+Type type_register(const TypeInfo *info);
+
+/**
+ * object_class_dynamic_cast_assert:
+ * @klass: The #ObjectClass to attempt to cast.
+ * @typename: The QOM typename of the class to cast to.
+ *
+ * See object_class_dynamic_cast() for a description of the parameters
+ * of this function. The only difference in behavior is that this function
+ * asserts instead of returning #NULL on failure if QOM cast debugging is
+ * enabled. This function is not meant to be called directly, but only through
+ * the wrapper macros OBJECT_CLASS_CHECK and INTERFACE_CHECK.
+ */
+ObjectClass *object_class_dynamic_cast_assert(ObjectClass *klass,
+ const char *typename,
+ const char *file, int line,
+ const char *func);
+
+/**
+ * object_class_dynamic_cast:
+ * @klass: The #ObjectClass to attempt to cast.
+ * @typename: The QOM typename of the class to cast to.
+ *
+ * Returns: If @typename is a class, this function returns @klass if
+ * @typename is a subtype of @klass, else returns #NULL.
+ *
+ * If @typename is an interface, this function returns the interface
+ * definition for @klass if @klass implements it unambiguously; #NULL
+ * is returned if @klass does not implement the interface or if multiple
+ * classes or interfaces on the hierarchy leading to @klass implement
+ * it. (FIXME: perhaps this can be detected at type definition time?)
+ */
+ObjectClass *object_class_dynamic_cast(ObjectClass *klass,
+ const char *typename);
+
+/**
+ * object_class_get_parent:
+ * @klass: The class to obtain the parent for.
+ *
+ * Returns: The parent for @klass or %NULL if none.
+ */
+ObjectClass *object_class_get_parent(ObjectClass *klass);
+
+/**
+ * object_class_get_name:
+ * @klass: The class to obtain the QOM typename for.
+ *
+ * Returns: The QOM typename for @klass.
+ */
+const char *object_class_get_name(ObjectClass *klass);
+
+/**
+ * object_class_is_abstract:
+ * @klass: The class to obtain the abstractness for.
+ *
+ * Returns: %true if @klass is abstract, %false otherwise.
+ */
+bool object_class_is_abstract(ObjectClass *klass);
+
+/**
+ * object_class_by_name:
+ * @typename: The QOM typename to obtain the class for.
+ *
+ * Returns: The class for @typename or %NULL if not found.
+ */
+ObjectClass *object_class_by_name(const char *typename);
+
+void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
+ const char *implements_type, bool include_abstract,
+ void *opaque);
+
+/**
+ * object_class_get_list:
+ * @implements_type: The type to filter for, including its derivatives.
+ * @include_abstract: Whether to include abstract classes.
+ *
+ * Returns: A singly-linked list of the classes in reverse hashtable order.
+ */
+GSList *object_class_get_list(const char *implements_type,
+ bool include_abstract);
+
+/**
+ * object_ref:
+ * @obj: the object
+ *
+ * Increase the reference count of a object. A object cannot be freed as long
+ * as its reference count is greater than zero.
+ */
+void object_ref(Object *obj);
+
+/**
+ * qdef_unref:
+ * @obj: the object
+ *
+ * Decrease the reference count of a object. A object cannot be freed as long
+ * as its reference count is greater than zero.
+ */
+void object_unref(Object *obj);
+
+/**
+ * object_property_add:
+ * @obj: the object to add a property to
+ * @name: the name of the property. This can contain any character except for
+ * a forward slash. In general, you should use hyphens '-' instead of
+ * underscores '_' when naming properties.
+ * @type: the type name of the property. This namespace is pretty loosely
+ * defined. Sub namespaces are constructed by using a prefix and then
+ * to angle brackets. For instance, the type 'virtio-net-pci' in the
+ * 'link' namespace would be 'link<virtio-net-pci>'.
+ * @get: The getter to be called to read a property. If this is NULL, then
+ * the property cannot be read.
+ * @set: the setter to be called to write a property. If this is NULL,
+ * then the property cannot be written.
+ * @release: called when the property is removed from the object. This is
+ * meant to allow a property to free its opaque upon object
+ * destruction. This may be NULL.
+ * @opaque: an opaque pointer to pass to the callbacks for the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: The #ObjectProperty; this can be used to set the @resolve
+ * callback for child and link properties.
+ */
+ObjectProperty *object_property_add(Object *obj, const char *name,
+ const char *type,
+ ObjectPropertyAccessor *get,
+ ObjectPropertyAccessor *set,
+ ObjectPropertyRelease *release,
+ void *opaque, Error **errp);
+
+void object_property_del(Object *obj, const char *name, Error **errp);
+
+/**
+ * object_property_find:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Look up a property for an object and return its #ObjectProperty if found.
+ */
+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
+ *
+ * <example>
+ * <title>Using object property iterators</title>
+ * <programlisting>
+ * 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);
+ * </programlisting>
+ * </example>
+ *
+ * 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);
+
+/**
+ * object_property_get:
+ * @obj: the object
+ * @v: the visitor that will receive the property value. This should be an
+ * Output visitor and the data will be written with @name as the name.
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Reads a property from a object.
+ */
+void object_property_get(Object *obj, struct Visitor *v, const char *name,
+ Error **errp);
+
+/**
+ * object_property_set_str:
+ * @value: the value to be written to the property
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Writes a string value to a property.
+ */
+void object_property_set_str(Object *obj, const char *value,
+ const char *name, Error **errp);
+
+/**
+ * object_property_get_str:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, converted to a C string, or NULL if
+ * an error occurs (including when the property value is not a string).
+ * The caller should free the string.
+ */
+char *object_property_get_str(Object *obj, const char *name,
+ Error **errp);
+
+/**
+ * object_property_set_link:
+ * @value: the value to be written to the property
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Writes an object's canonical path to a property.
+ */
+void object_property_set_link(Object *obj, Object *value,
+ const char *name, Error **errp);
+
+/**
+ * object_property_get_link:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, resolved from a path to an Object,
+ * or NULL if an error occurs (including when the property value is not a
+ * string or not a valid object path).
+ */
+Object *object_property_get_link(Object *obj, const char *name,
+ Error **errp);
+
+/**
+ * object_property_set_bool:
+ * @value: the value to be written to the property
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Writes a bool value to a property.
+ */
+void object_property_set_bool(Object *obj, bool value,
+ const char *name, Error **errp);
+
+/**
+ * object_property_get_bool:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, converted to a boolean, or NULL if
+ * an error occurs (including when the property value is not a bool).
+ */
+bool object_property_get_bool(Object *obj, const char *name,
+ Error **errp);
+
+/**
+ * object_property_set_int:
+ * @value: the value to be written to the property
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Writes an integer value to a property.
+ */
+void object_property_set_int(Object *obj, int64_t value,
+ const char *name, Error **errp);
+
+/**
+ * object_property_get_int:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, converted to an integer, or NULL if
+ * an error occurs (including when the property value is not an integer).
+ */
+int64_t object_property_get_int(Object *obj, const char *name,
+ Error **errp);
+
+/**
+ * object_property_get_enum:
+ * @obj: the object
+ * @name: the name of the property
+ * @typename: the name of the enum data type
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, converted to an integer, or
+ * undefined if an error occurs (including when the property value is not
+ * an enum).
+ */
+int object_property_get_enum(Object *obj, const char *name,
+ const char *typename, Error **errp);
+
+/**
+ * object_property_get_uint16List:
+ * @obj: the object
+ * @name: the name of the property
+ * @list: the returned int list
+ * @errp: returns an error if this function fails
+ *
+ * Returns: the value of the property, converted to integers, or
+ * undefined if an error occurs (including when the property value is not
+ * an list of integers).
+ */
+void object_property_get_uint16List(Object *obj, const char *name,
+ uint16List **list, Error **errp);
+
+/**
+ * object_property_set:
+ * @obj: the object
+ * @v: the visitor that will be used to write the property value. This should
+ * be an Input visitor and the data will be first read with @name as the
+ * name and then written as the property value.
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Writes a property to a object.
+ */
+void object_property_set(Object *obj, struct Visitor *v, const char *name,
+ Error **errp);
+
+/**
+ * object_property_parse:
+ * @obj: the object
+ * @string: the string that will be used to parse the property value.
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Parses a string and writes the result into a property of an object.
+ */
+void object_property_parse(Object *obj, const char *string,
+ const char *name, Error **errp);
+
+/**
+ * object_property_print:
+ * @obj: the object
+ * @name: the name of the property
+ * @human: if true, print for human consumption
+ * @errp: returns an error if this function fails
+ *
+ * Returns a string representation of the value of the property. The
+ * caller shall free the string.
+ */
+char *object_property_print(Object *obj, const char *name, bool human,
+ Error **errp);
+
+/**
+ * object_property_get_type:
+ * @obj: the object
+ * @name: the name of the property
+ * @errp: returns an error if this function fails
+ *
+ * Returns: The type name of the property.
+ */
+const char *object_property_get_type(Object *obj, const char *name,
+ Error **errp);
+
+/**
+ * object_get_root:
+ *
+ * Returns: the root object of the composition tree
+ */
+Object *object_get_root(void);
+
+
+/**
+ * object_get_objects_root:
+ *
+ * Get the container object that holds user created
+ * object instances. This is the object at path
+ * "/objects"
+ *
+ * Returns: the user object container
+ */
+Object *object_get_objects_root(void);
+
+/**
+ * object_get_canonical_path_component:
+ *
+ * Returns: The final component in the object's canonical path. The canonical
+ * path is the path within the composition tree starting from the root.
+ */
+gchar *object_get_canonical_path_component(Object *obj);
+
+/**
+ * object_get_canonical_path:
+ *
+ * Returns: The canonical path for a object. This is the path within the
+ * composition tree starting from the root.
+ */
+gchar *object_get_canonical_path(Object *obj);
+
+/**
+ * object_resolve_path:
+ * @path: the path to resolve
+ * @ambiguous: returns true if the path resolution failed because of an
+ * ambiguous match
+ *
+ * There are two types of supported paths--absolute paths and partial paths.
+ *
+ * Absolute paths are derived from the root object and can follow child<> or
+ * link<> properties. Since they can follow link<> properties, they can be
+ * arbitrarily long. Absolute paths look like absolute filenames and are
+ * prefixed with a leading slash.
+ *
+ * Partial paths look like relative filenames. They do not begin with a
+ * prefix. The matching rules for partial paths are subtle but designed to make
+ * specifying objects easy. At each level of the composition tree, the partial
+ * path is matched as an absolute path. The first match is not returned. At
+ * least two matches are searched for. A successful result is only returned if
+ * only one match is found. If more than one match is found, a flag is
+ * returned to indicate that the match was ambiguous.
+ *
+ * Returns: The matched object or NULL on path lookup failure.
+ */
+Object *object_resolve_path(const char *path, bool *ambiguous);
+
+/**
+ * object_resolve_path_type:
+ * @path: the path to resolve
+ * @typename: the type to look for.
+ * @ambiguous: returns true if the path resolution failed because of an
+ * ambiguous match
+ *
+ * This is similar to object_resolve_path. However, when looking for a
+ * partial path only matches that implement the given type are considered.
+ * This restricts the search and avoids spuriously flagging matches as
+ * ambiguous.
+ *
+ * For both partial and absolute paths, the return value goes through
+ * a dynamic cast to @typename. This is important if either the link,
+ * or the typename itself are of interface types.
+ *
+ * Returns: The matched object or NULL on path lookup failure.
+ */
+Object *object_resolve_path_type(const char *path, const char *typename,
+ bool *ambiguous);
+
+/**
+ * object_resolve_path_component:
+ * @parent: the object in which to resolve the path
+ * @part: the component to resolve.
+ *
+ * This is similar to object_resolve_path with an absolute path, but it
+ * only resolves one element (@part) and takes the others from @parent.
+ *
+ * Returns: The resolved object or NULL on path lookup failure.
+ */
+Object *object_resolve_path_component(Object *parent, const gchar *part);
+
+/**
+ * object_property_add_child:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @child: the child object
+ * @errp: if an error occurs, a pointer to an area to store the area
+ *
+ * Child properties form the composition tree. All objects need to be a child
+ * of another object. Objects can only be a child of one object.
+ *
+ * There is no way for a child to determine what its parent is. It is not
+ * a bidirectional relationship. This is by design.
+ *
+ * The value of a child property as a C string will be the child object's
+ * canonical path. It can be retrieved using object_property_get_str().
+ * The child object itself can be retrieved using object_property_get_link().
+ */
+void object_property_add_child(Object *obj, const char *name,
+ Object *child, Error **errp);
+
+typedef enum {
+ /* Unref the link pointer when the property is deleted */
+ OBJ_PROP_LINK_UNREF_ON_RELEASE = 0x1,
+} ObjectPropertyLinkFlags;
+
+/**
+ * object_property_allow_set_link:
+ *
+ * The default implementation of the object_property_add_link() check()
+ * callback function. It allows the link property to be set and never returns
+ * an error.
+ */
+void object_property_allow_set_link(Object *, const char *,
+ Object *, Error **);
+
+/**
+ * object_property_add_link:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @type: the qobj type of the link
+ * @child: a pointer to where the link object reference is stored
+ * @check: callback to veto setting or NULL if the property is read-only
+ * @flags: additional options for the link
+ * @errp: if an error occurs, a pointer to an area to store the area
+ *
+ * Links establish relationships between objects. Links are unidirectional
+ * although two links can be combined to form a bidirectional relationship
+ * between objects.
+ *
+ * Links form the graph in the object model.
+ *
+ * The <code>@check()</code> callback is invoked when
+ * object_property_set_link() is called and can raise an error to prevent the
+ * link being set. If <code>@check</code> is NULL, the property is read-only
+ * and cannot be set.
+ *
+ * Ownership of the pointer that @child points to is transferred to the
+ * link property. The reference count for <code>*@child</code> is
+ * managed by the property from after the function returns till the
+ * property is deleted with object_property_del(). If the
+ * <code>@flags</code> <code>OBJ_PROP_LINK_UNREF_ON_RELEASE</code> bit is set,
+ * the reference count is decremented when the property is deleted.
+ */
+void object_property_add_link(Object *obj, const char *name,
+ const char *type, Object **child,
+ void (*check)(Object *obj, const char *name,
+ Object *val, Error **errp),
+ ObjectPropertyLinkFlags flags,
+ Error **errp);
+
+/**
+ * object_property_add_str:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @get: the getter or NULL if the property is write-only. This function must
+ * return a string to be freed by g_free().
+ * @set: the setter or NULL if the property is read-only
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add a string property using getters/setters. This function will add a
+ * property of type 'string'.
+ */
+void object_property_add_str(Object *obj, const char *name,
+ char *(*get)(Object *, Error **),
+ void (*set)(Object *, const char *, Error **),
+ Error **errp);
+
+/**
+ * object_property_add_bool:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @get: the getter or NULL if the property is write-only.
+ * @set: the setter or NULL if the property is read-only
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add a bool property using getters/setters. This function will add a
+ * property of type 'bool'.
+ */
+void object_property_add_bool(Object *obj, const char *name,
+ bool (*get)(Object *, Error **),
+ void (*set)(Object *, bool, Error **),
+ Error **errp);
+
+/**
+ * object_property_add_enum:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @typename: the name of the enum data type
+ * @get: the getter or %NULL if the property is write-only.
+ * @set: the setter or %NULL if the property is read-only
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an enum property using getters/setters. This function will add a
+ * property of type '@typename'.
+ */
+void object_property_add_enum(Object *obj, const char *name,
+ const char *typename,
+ const char * const *strings,
+ int (*get)(Object *, Error **),
+ void (*set)(Object *, int, Error **),
+ Error **errp);
+
+/**
+ * object_property_add_tm:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @get: the getter or NULL if the property is write-only.
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add a read-only struct tm valued property using a getter function.
+ * This function will add a property of type 'struct tm'.
+ */
+void object_property_add_tm(Object *obj, const char *name,
+ void (*get)(Object *, struct tm *, Error **),
+ Error **errp);
+
+/**
+ * object_property_add_uint8_ptr:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @v: pointer to value
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an integer property in memory. This function will add a
+ * property of type 'uint8'.
+ */
+void object_property_add_uint8_ptr(Object *obj, const char *name,
+ const uint8_t *v, Error **errp);
+
+/**
+ * object_property_add_uint16_ptr:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @v: pointer to value
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an integer property in memory. This function will add a
+ * property of type 'uint16'.
+ */
+void object_property_add_uint16_ptr(Object *obj, const char *name,
+ const uint16_t *v, Error **errp);
+
+/**
+ * object_property_add_uint32_ptr:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @v: pointer to value
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an integer property in memory. This function will add a
+ * property of type 'uint32'.
+ */
+void object_property_add_uint32_ptr(Object *obj, const char *name,
+ const uint32_t *v, Error **errp);
+
+/**
+ * object_property_add_uint64_ptr:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @v: pointer to value
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an integer property in memory. This function will add a
+ * property of type 'uint64'.
+ */
+void object_property_add_uint64_ptr(Object *obj, const char *name,
+ const uint64_t *v, Error **Errp);
+
+/**
+ * object_property_add_alias:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @target_obj: the object to forward property access to
+ * @target_name: the name of the property on the forwarded object
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an alias for a property on an object. This function will add a property
+ * of the same type as the forwarded property.
+ *
+ * The caller must ensure that <code>@target_obj</code> stays alive as long as
+ * this property exists. In the case of a child object or an alias on the same
+ * object this will be the case. For aliases to other objects the caller is
+ * responsible for taking a reference.
+ */
+void object_property_add_alias(Object *obj, const char *name,
+ Object *target_obj, const char *target_name,
+ Error **errp);
+
+/**
+ * object_property_add_const_link:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @target: the object to be referred by the link
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add an unmodifiable link for a property on an object. This function will
+ * add a property of type link<TYPE> where TYPE is the type of @target.
+ *
+ * The caller must ensure that @target stays alive as long as
+ * this property exists. In the case @target is a child of @obj,
+ * this will be the case. Otherwise, the caller is responsible for
+ * taking a reference.
+ */
+void object_property_add_const_link(Object *obj, const char *name,
+ Object *target, Error **errp);
+
+/**
+ * object_property_set_description:
+ * @obj: the object owning the property
+ * @name: the name of the property
+ * @description: the description of the property on the object
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Set an object property's description.
+ *
+ */
+void object_property_set_description(Object *obj, const char *name,
+ const char *description, Error **errp);
+
+/**
+ * object_child_foreach:
+ * @obj: the object whose children will be navigated
+ * @fn: the iterator function to be called
+ * @opaque: an opaque value that will be passed to the iterator
+ *
+ * Call @fn passing each child of @obj and @opaque to it, until @fn returns
+ * non-zero.
+ *
+ * It is forbidden to add or remove children from @obj from the @fn
+ * callback.
+ *
+ * Returns: The last value returned by @fn, or 0 if there is no child.
+ */
+int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
+ void *opaque);
+
+/**
+ * object_child_foreach_recursive:
+ * @obj: the object whose children will be navigated
+ * @fn: the iterator function to be called
+ * @opaque: an opaque value that will be passed to the iterator
+ *
+ * Call @fn passing each child of @obj and @opaque to it, until @fn returns
+ * non-zero. Calls recursively, all child nodes of @obj will also be passed
+ * all the way down to the leaf nodes of the tree. Depth first ordering.
+ *
+ * It is forbidden to add or remove children from @obj (or its
+ * child nodes) from the @fn callback.
+ *
+ * Returns: The last value returned by @fn, or 0 if there is no child.
+ */
+int object_child_foreach_recursive(Object *obj,
+ int (*fn)(Object *child, void *opaque),
+ void *opaque);
+/**
+ * container_get:
+ * @root: root of the #path, e.g., object_get_root()
+ * @path: path to the container
+ *
+ * Return a container object whose path is @path. Create more containers
+ * along the path if necessary.
+ *
+ * Returns: the container object.
+ */
+Object *container_get(Object *root, const char *path);
+
+#undef Type
+#undef class
+#undef typename
+
+#endif
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