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/*
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* QEMU Object Model
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*
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* Copyright IBM, Corp. 2011
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*
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* Authors:
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* Anthony Liguori <aliguori@us.ibm.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2 or later.
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* See the COPYING file in the top-level directory.
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*
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*/
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#ifndef QEMU_OBJECT_H
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#define QEMU_OBJECT_H
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#include <glib.h> |
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#include <stdint.h> |
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#include <stdbool.h> |
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#include "qemu/queue.h" |
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struct Visitor;
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struct Error;
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struct TypeImpl;
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typedef struct TypeImpl *Type; |
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typedef struct ObjectClass ObjectClass; |
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typedef struct Object Object; |
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typedef struct TypeInfo TypeInfo; |
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typedef struct InterfaceClass InterfaceClass; |
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typedef struct InterfaceInfo InterfaceInfo; |
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#define TYPE_OBJECT "object" |
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/**
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* SECTION:object.h
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* @title:Base Object Type System
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* @short_description: interfaces for creating new types and objects
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*
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* The QEMU Object Model provides a framework for registering user creatable
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* types and instantiating objects from those types. QOM provides the following
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* features:
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*
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* - System for dynamically registering types
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* - Support for single-inheritance of types
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* - Multiple inheritance of stateless interfaces
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*
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* <example>
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* <title>Creating a minimal type</title>
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* <programlisting>
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* #include "qdev.h"
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*
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* #define TYPE_MY_DEVICE "my-device"
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*
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* // No new virtual functions: we can reuse the typedef for the
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* // superclass.
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* typedef DeviceClass MyDeviceClass;
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* typedef struct MyDevice
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* {
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* DeviceState parent;
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*
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* int reg0, reg1, reg2;
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* } MyDevice;
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*
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* static const TypeInfo my_device_info = {
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* .name = TYPE_MY_DEVICE,
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* .parent = TYPE_DEVICE,
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* .instance_size = sizeof(MyDevice),
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* };
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*
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* static void my_device_register_types(void)
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* {
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* type_register_static(&my_device_info);
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* }
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*
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* type_init(my_device_register_types)
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* </programlisting>
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* </example>
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*
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* In the above example, we create a simple type that is described by #TypeInfo.
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* #TypeInfo describes information about the type including what it inherits
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* from, the instance and class size, and constructor/destructor hooks.
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*
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* Every type has an #ObjectClass associated with it. #ObjectClass derivatives
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* are instantiated dynamically but there is only ever one instance for any
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* given type. The #ObjectClass typically holds a table of function pointers
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* for the virtual methods implemented by this type.
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*
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* Using object_new(), a new #Object derivative will be instantiated. You can
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* cast an #Object to a subclass (or base-class) type using
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* object_dynamic_cast(). You typically want to define macro wrappers around
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* OBJECT_CHECK() and OBJECT_CLASS_CHECK() to make it easier to convert to a
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* specific type:
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*
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* <example>
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* <title>Typecasting macros</title>
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* <programlisting>
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* #define MY_DEVICE_GET_CLASS(obj) \
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* OBJECT_GET_CLASS(MyDeviceClass, obj, TYPE_MY_DEVICE)
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* #define MY_DEVICE_CLASS(klass) \
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* OBJECT_CLASS_CHECK(MyDeviceClass, klass, TYPE_MY_DEVICE)
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* #define MY_DEVICE(obj) \
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* OBJECT_CHECK(MyDevice, obj, TYPE_MY_DEVICE)
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* </programlisting>
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* </example>
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*
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* # Class Initialization #
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*
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* Before an object is initialized, the class for the object must be
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* initialized. There is only one class object for all instance objects
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* that is created lazily.
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*
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* Classes are initialized by first initializing any parent classes (if
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* necessary). After the parent class object has initialized, it will be
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* copied into the current class object and any additional storage in the
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* class object is zero filled.
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*
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* The effect of this is that classes automatically inherit any virtual
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* function pointers that the parent class has already initialized. All
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* other fields will be zero filled.
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*
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* Once all of the parent classes have been initialized, #TypeInfo::class_init
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* is called to let the class being instantiated provide default initialize for
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* its virtual functions. Here is how the above example might be modified
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* to introduce an overridden virtual function:
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*
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* <example>
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* <title>Overriding a virtual function</title>
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* <programlisting>
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* #include "qdev.h"
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*
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* void my_device_class_init(ObjectClass *klass, void *class_data)
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* {
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* DeviceClass *dc = DEVICE_CLASS(klass);
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* dc->reset = my_device_reset;
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* }
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*
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* static const TypeInfo my_device_info = {
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* .name = TYPE_MY_DEVICE,
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* .parent = TYPE_DEVICE,
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* .instance_size = sizeof(MyDevice),
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* .class_init = my_device_class_init,
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* };
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* </programlisting>
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* </example>
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*
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* Introducing new virtual methods requires a class to define its own
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* struct and to add a .class_size member to the #TypeInfo. Each method
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* will also have a wrapper function to call it easily:
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*
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* <example>
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* <title>Defining an abstract class</title>
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* <programlisting>
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* #include "qdev.h"
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*
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* typedef struct MyDeviceClass
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* {
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* DeviceClass parent;
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*
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* void (*frobnicate) (MyDevice *obj);
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* } MyDeviceClass;
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*
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* static const TypeInfo my_device_info = {
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* .name = TYPE_MY_DEVICE,
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* .parent = TYPE_DEVICE,
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* .instance_size = sizeof(MyDevice),
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* .abstract = true, // or set a default in my_device_class_init
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* .class_size = sizeof(MyDeviceClass),
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* };
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*
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* void my_device_frobnicate(MyDevice *obj)
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* {
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* MyDeviceClass *klass = MY_DEVICE_GET_CLASS(obj);
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*
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* klass->frobnicate(obj);
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* }
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* </programlisting>
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* </example>
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*
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* # Interfaces #
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*
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* Interfaces allow a limited form of multiple inheritance. Instances are
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* similar to normal types except for the fact that are only defined by
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* their classes and never carry any state. You can dynamically cast an object
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* to one of its #Interface types and vice versa.
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*
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* # Methods #
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*
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* A <emphasis>method</emphasis> is a function within the namespace scope of
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* a class. It usually operates on the object instance by passing it as a
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* strongly-typed first argument.
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* If it does not operate on an object instance, it is dubbed
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* <emphasis>class method</emphasis>.
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*
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* Methods cannot be overloaded. That is, the #ObjectClass and method name
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* uniquely identity the function to be called; the signature does not vary
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* except for trailing varargs.
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*
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* Methods are always <emphasis>virtual</emphasis>. Overriding a method in
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* #TypeInfo.class_init of a subclass leads to any user of the class obtained
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* via OBJECT_GET_CLASS() accessing the overridden function.
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* The original function is not automatically invoked. It is the responsability
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* of the overriding class to determine whether and when to invoke the method
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* being overridden.
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*
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* To invoke the method being overridden, the preferred solution is to store
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* the original value in the overriding class before overriding the method.
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* This corresponds to |[ {super,base}.method(...) ]| in Java and C#
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* respectively; this frees the overriding class from hardcoding its parent
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* class, which someone might choose to change at some point.
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*
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* <example>
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* <title>Overriding a virtual method</title>
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* <programlisting>
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* typedef struct MyState MyState;
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*
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* typedef void (*MyDoSomething)(MyState *obj);
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*
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* typedef struct MyClass {
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* ObjectClass parent_class;
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*
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* MyDoSomething do_something;
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* } MyClass;
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*
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* static void my_do_something(MyState *obj)
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* {
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* // do something
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* }
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*
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* static void my_class_init(ObjectClass *oc, void *data)
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* {
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* MyClass *mc = MY_CLASS(oc);
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*
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* mc->do_something = my_do_something;
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* }
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*
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* static const TypeInfo my_type_info = {
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* .name = TYPE_MY,
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* .parent = TYPE_OBJECT,
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* .instance_size = sizeof(MyState),
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* .class_size = sizeof(MyClass),
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* .class_init = my_class_init,
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* };
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*
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* typedef struct DerivedClass {
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* MyClass parent_class;
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*
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* MyDoSomething parent_do_something;
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* } MyClass;
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*
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* static void derived_do_something(MyState *obj)
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* {
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* DerivedClass *dc = DERIVED_GET_CLASS(obj);
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*
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* // do something here
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* dc->parent_do_something(obj);
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* // do something else here
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* }
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*
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* static void derived_class_init(ObjectClass *oc, void *data)
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* {
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* MyClass *mc = MY_CLASS(oc);
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* DerivedClass *dc = DERIVED_CLASS(oc);
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*
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* dc->parent_do_something = mc->do_something;
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* mc->do_something = derived_do_something;
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* }
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*
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* static const TypeInfo derived_type_info = {
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* .name = TYPE_DERIVED,
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* .parent = TYPE_MY,
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* .class_size = sizeof(DerivedClass),
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* .class_init = my_class_init,
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* };
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* </programlisting>
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* </example>
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*
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* Alternatively, object_class_by_name() can be used to obtain the class and
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* its non-overridden methods for a specific type. This would correspond to
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* |[ MyClass::method(...) ]| in C++.
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*
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* The first example of such a QOM method was #CPUClass.reset,
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* another example is #DeviceClass.realize.
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*/
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/**
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* ObjectPropertyAccessor:
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* @obj: the object that owns the property
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* @v: the visitor that contains the property data
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* @opaque: the object property opaque
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* @name: the name of the property
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* @errp: a pointer to an Error that is filled if getting/setting fails.
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*
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* Called when trying to get/set a property.
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*/
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typedef void (ObjectPropertyAccessor)(Object *obj, |
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struct Visitor *v,
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void *opaque,
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const char *name, |
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struct Error **errp);
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/**
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* ObjectPropertyRelease:
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* @obj: the object that owns the property
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* @name: the name of the property
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* @opaque: the opaque registered with the property
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*
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* Called when a property is removed from a object.
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*/
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typedef void (ObjectPropertyRelease)(Object *obj, |
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const char *name, |
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void *opaque);
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typedef struct ObjectProperty |
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{ |
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gchar *name; |
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gchar *type; |
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ObjectPropertyAccessor *get; |
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ObjectPropertyAccessor *set; |
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ObjectPropertyRelease *release; |
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void *opaque;
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QTAILQ_ENTRY(ObjectProperty) node; |
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} ObjectProperty; |
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/**
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* ObjectUnparent:
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* @obj: the object that is being removed from the composition tree
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*
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* Called when an object is being removed from the QOM composition tree.
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* The function should remove any backlinks from children objects to @obj.
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*/
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typedef void (ObjectUnparent)(Object *obj); |
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/**
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* ObjectFree:
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* @obj: the object being freed
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*
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* Called when an object's last reference is removed.
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*/
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typedef void (ObjectFree)(void *obj); |
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/**
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* ObjectClass:
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*
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* The base for all classes. The only thing that #ObjectClass contains is an
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* integer type handle.
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*/
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struct ObjectClass
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{ |
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/*< private >*/
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Type type; |
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GSList *interfaces; |
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ObjectUnparent *unparent; |
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}; |
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/**
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* Object:
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*
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* The base for all objects. The first member of this object is a pointer to
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* a #ObjectClass. Since C guarantees that the first member of a structure
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* always begins at byte 0 of that structure, as long as any sub-object places
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* its parent as the first member, we can cast directly to a #Object.
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*
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* As a result, #Object contains a reference to the objects type as its
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* first member. This allows identification of the real type of the object at
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* run time.
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*
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* #Object also contains a list of #Interfaces that this object
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* implements.
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*/
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struct Object
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{ |
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/*< private >*/
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ObjectClass *class; |
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ObjectFree *free; |
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QTAILQ_HEAD(, ObjectProperty) properties; |
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uint32_t ref; |
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Object *parent; |
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}; |
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/**
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* TypeInfo:
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* @name: The name of the type.
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* @parent: The name of the parent type.
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* @instance_size: The size of the object (derivative of #Object). If
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* @instance_size is 0, then the size of the object will be the size of the
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* parent object.
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* @instance_init: This function is called to initialize an object. The parent
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* class will have already been initialized so the type is only responsible
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* for initializing its own members.
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* @instance_finalize: This function is called during object destruction. This
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* is called before the parent @instance_finalize function has been called.
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* An object should only free the members that are unique to its type in this
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* function.
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* @abstract: If this field is true, then the class is considered abstract and
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* cannot be directly instantiated.
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* @class_size: The size of the class object (derivative of #ObjectClass)
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* for this object. If @class_size is 0, then the size of the class will be
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* assumed to be the size of the parent class. This allows a type to avoid
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* implementing an explicit class type if they are not adding additional
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* virtual functions.
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* @class_init: This function is called after all parent class initialization
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* has occurred to allow a class to set its default virtual method pointers.
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* This is also the function to use to override virtual methods from a parent
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* class.
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* @class_base_init: This function is called for all base classes after all
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* parent class initialization has occurred, but before the class itself
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* is initialized. This is the function to use to undo the effects of
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* memcpy from the parent class to the descendents.
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* @class_finalize: This function is called during class destruction and is
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* meant to release and dynamic parameters allocated by @class_init.
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* @class_data: Data to pass to the @class_init, @class_base_init and
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* @class_finalize functions. This can be useful when building dynamic
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* classes.
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* @interfaces: The list of interfaces associated with this type. This
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* should point to a static array that's terminated with a zero filled
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* element.
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*/
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struct TypeInfo
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{ |
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const char *name; |
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const char *parent; |
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size_t instance_size; |
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void (*instance_init)(Object *obj);
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void (*instance_finalize)(Object *obj);
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bool abstract;
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size_t class_size; |
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void (*class_init)(ObjectClass *klass, void *data); |
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void (*class_base_init)(ObjectClass *klass, void *data); |
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void (*class_finalize)(ObjectClass *klass, void *data); |
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void *class_data;
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InterfaceInfo *interfaces; |
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}; |
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/**
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* OBJECT:
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* @obj: A derivative of #Object
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*
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* Converts an object to a #Object. Since all objects are #Objects,
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* this function will always succeed.
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*/
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#define OBJECT(obj) \
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((Object *)(obj)) |
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/**
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* OBJECT_CLASS:
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* @class: A derivative of #ObjectClass.
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*
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* Converts a class to an #ObjectClass. Since all objects are #Objects,
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* this function will always succeed.
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*/
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#define OBJECT_CLASS(class) \
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((ObjectClass *)(class)) |
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/**
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* OBJECT_CHECK:
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* @type: The C type to use for the return value.
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* @obj: A derivative of @type to cast.
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* @name: The QOM typename of @type
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*
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* A type safe version of @object_dynamic_cast_assert. Typically each class
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* will define a macro based on this type to perform type safe dynamic_casts to
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* this object type.
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*
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* If an invalid object is passed to this function, a run time assert will be
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* generated.
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*/
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#define OBJECT_CHECK(type, obj, name) \
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((type *)object_dynamic_cast_assert(OBJECT(obj), (name))) |
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/**
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* OBJECT_CLASS_CHECK:
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* @class: The C type to use for the return value.
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* @obj: A derivative of @type to cast.
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* @name: the QOM typename of @class.
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*
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* A type safe version of @object_class_dynamic_cast_assert. This macro is
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* typically wrapped by each type to perform type safe casts of a class to a
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* specific class type.
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*/
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#define OBJECT_CLASS_CHECK(class, obj, name) \
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((class *)object_class_dynamic_cast_assert(OBJECT_CLASS(obj), (name))) |
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/**
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* OBJECT_GET_CLASS:
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* @class: The C type to use for the return value.
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* @obj: The object to obtain the class for.
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* @name: The QOM typename of @obj.
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*
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* This function will return a specific class for a given object. Its generally
|
501 |
* used by each type to provide a type safe macro to get a specific class type
|
502 |
* from an object.
|
503 |
*/
|
504 |
#define OBJECT_GET_CLASS(class, obj, name) \
|
505 |
OBJECT_CLASS_CHECK(class, object_get_class(OBJECT(obj)), name) |
506 |
|
507 |
/**
|
508 |
* InterfaceInfo:
|
509 |
* @type: The name of the interface.
|
510 |
*
|
511 |
* The information associated with an interface.
|
512 |
*/
|
513 |
struct InterfaceInfo {
|
514 |
const char *type; |
515 |
}; |
516 |
|
517 |
/**
|
518 |
* InterfaceClass:
|
519 |
* @parent_class: the base class
|
520 |
*
|
521 |
* The class for all interfaces. Subclasses of this class should only add
|
522 |
* virtual methods.
|
523 |
*/
|
524 |
struct InterfaceClass
|
525 |
{ |
526 |
ObjectClass parent_class; |
527 |
/*< private >*/
|
528 |
ObjectClass *concrete_class; |
529 |
}; |
530 |
|
531 |
#define TYPE_INTERFACE "interface" |
532 |
|
533 |
/**
|
534 |
* INTERFACE_CLASS:
|
535 |
* @klass: class to cast from
|
536 |
* Returns: An #InterfaceClass or raise an error if cast is invalid
|
537 |
*/
|
538 |
#define INTERFACE_CLASS(klass) \
|
539 |
OBJECT_CLASS_CHECK(InterfaceClass, klass, TYPE_INTERFACE) |
540 |
|
541 |
/**
|
542 |
* INTERFACE_CHECK:
|
543 |
* @interface: the type to return
|
544 |
* @obj: the object to convert to an interface
|
545 |
* @name: the interface type name
|
546 |
*
|
547 |
* Returns: @obj casted to @interface if cast is valid, otherwise raise error.
|
548 |
*/
|
549 |
#define INTERFACE_CHECK(interface, obj, name) \
|
550 |
((interface *)object_dynamic_cast_assert(OBJECT((obj)), (name))) |
551 |
|
552 |
/**
|
553 |
* object_new:
|
554 |
* @typename: The name of the type of the object to instantiate.
|
555 |
*
|
556 |
* This function will initialize a new object using heap allocated memory.
|
557 |
* The returned object has a reference count of 1, and will be freed when
|
558 |
* the last reference is dropped.
|
559 |
*
|
560 |
* Returns: The newly allocated and instantiated object.
|
561 |
*/
|
562 |
Object *object_new(const char *typename); |
563 |
|
564 |
/**
|
565 |
* object_new_with_type:
|
566 |
* @type: The type of the object to instantiate.
|
567 |
*
|
568 |
* This function will initialize a new object using heap allocated memory.
|
569 |
* The returned object has a reference count of 1, and will be freed when
|
570 |
* the last reference is dropped.
|
571 |
*
|
572 |
* Returns: The newly allocated and instantiated object.
|
573 |
*/
|
574 |
Object *object_new_with_type(Type type); |
575 |
|
576 |
/**
|
577 |
* object_initialize_with_type:
|
578 |
* @obj: A pointer to the memory to be used for the object.
|
579 |
* @type: The type of the object to instantiate.
|
580 |
*
|
581 |
* This function will initialize an object. The memory for the object should
|
582 |
* have already been allocated. The returned object has a reference count of 1,
|
583 |
* and will be finalized when the last reference is dropped.
|
584 |
*/
|
585 |
void object_initialize_with_type(void *data, Type type); |
586 |
|
587 |
/**
|
588 |
* object_initialize:
|
589 |
* @obj: A pointer to the memory to be used for the object.
|
590 |
* @typename: The name of the type of the object to instantiate.
|
591 |
*
|
592 |
* This function will initialize an object. The memory for the object should
|
593 |
* have already been allocated. The returned object has a reference count of 1,
|
594 |
* and will be finalized when the last reference is dropped.
|
595 |
*/
|
596 |
void object_initialize(void *obj, const char *typename); |
597 |
|
598 |
/**
|
599 |
* object_dynamic_cast:
|
600 |
* @obj: The object to cast.
|
601 |
* @typename: The @typename to cast to.
|
602 |
*
|
603 |
* This function will determine if @obj is-a @typename. @obj can refer to an
|
604 |
* object or an interface associated with an object.
|
605 |
*
|
606 |
* Returns: This function returns @obj on success or #NULL on failure.
|
607 |
*/
|
608 |
Object *object_dynamic_cast(Object *obj, const char *typename); |
609 |
|
610 |
/**
|
611 |
* object_dynamic_cast_assert:
|
612 |
*
|
613 |
* See object_dynamic_cast() for a description of the parameters of this
|
614 |
* function. The only difference in behavior is that this function asserts
|
615 |
* instead of returning #NULL on failure.
|
616 |
*/
|
617 |
Object *object_dynamic_cast_assert(Object *obj, const char *typename); |
618 |
|
619 |
/**
|
620 |
* object_get_class:
|
621 |
* @obj: A derivative of #Object
|
622 |
*
|
623 |
* Returns: The #ObjectClass of the type associated with @obj.
|
624 |
*/
|
625 |
ObjectClass *object_get_class(Object *obj); |
626 |
|
627 |
/**
|
628 |
* object_get_typename:
|
629 |
* @obj: A derivative of #Object.
|
630 |
*
|
631 |
* Returns: The QOM typename of @obj.
|
632 |
*/
|
633 |
const char *object_get_typename(Object *obj); |
634 |
|
635 |
/**
|
636 |
* type_register_static:
|
637 |
* @info: The #TypeInfo of the new type.
|
638 |
*
|
639 |
* @info and all of the strings it points to should exist for the life time
|
640 |
* that the type is registered.
|
641 |
*
|
642 |
* Returns: 0 on failure, the new #Type on success.
|
643 |
*/
|
644 |
Type type_register_static(const TypeInfo *info);
|
645 |
|
646 |
/**
|
647 |
* type_register:
|
648 |
* @info: The #TypeInfo of the new type
|
649 |
*
|
650 |
* Unlike type_register_static(), this call does not require @info or its
|
651 |
* string members to continue to exist after the call returns.
|
652 |
*
|
653 |
* Returns: 0 on failure, the new #Type on success.
|
654 |
*/
|
655 |
Type type_register(const TypeInfo *info);
|
656 |
|
657 |
/**
|
658 |
* object_class_dynamic_cast_assert:
|
659 |
* @klass: The #ObjectClass to attempt to cast.
|
660 |
* @typename: The QOM typename of the class to cast to.
|
661 |
*
|
662 |
* Returns: This function always returns @klass and asserts on failure.
|
663 |
*/
|
664 |
ObjectClass *object_class_dynamic_cast_assert(ObjectClass *klass, |
665 |
const char *typename); |
666 |
|
667 |
ObjectClass *object_class_dynamic_cast(ObjectClass *klass, |
668 |
const char *typename); |
669 |
|
670 |
/**
|
671 |
* object_class_get_parent:
|
672 |
* @klass: The class to obtain the parent for.
|
673 |
*
|
674 |
* Returns: The parent for @klass or %NULL if none.
|
675 |
*/
|
676 |
ObjectClass *object_class_get_parent(ObjectClass *klass); |
677 |
|
678 |
/**
|
679 |
* object_class_get_name:
|
680 |
* @klass: The class to obtain the QOM typename for.
|
681 |
*
|
682 |
* Returns: The QOM typename for @klass.
|
683 |
*/
|
684 |
const char *object_class_get_name(ObjectClass *klass); |
685 |
|
686 |
/**
|
687 |
* object_class_is_abstract:
|
688 |
* @klass: The class to obtain the abstractness for.
|
689 |
*
|
690 |
* Returns: %true if @klass is abstract, %false otherwise.
|
691 |
*/
|
692 |
bool object_class_is_abstract(ObjectClass *klass);
|
693 |
|
694 |
/**
|
695 |
* object_class_by_name:
|
696 |
* @typename: The QOM typename to obtain the class for.
|
697 |
*
|
698 |
* Returns: The class for @typename or %NULL if not found.
|
699 |
*/
|
700 |
ObjectClass *object_class_by_name(const char *typename); |
701 |
|
702 |
void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque), |
703 |
const char *implements_type, bool include_abstract, |
704 |
void *opaque);
|
705 |
|
706 |
/**
|
707 |
* object_class_get_list:
|
708 |
* @implements_type: The type to filter for, including its derivatives.
|
709 |
* @include_abstract: Whether to include abstract classes.
|
710 |
*
|
711 |
* Returns: A singly-linked list of the classes in reverse hashtable order.
|
712 |
*/
|
713 |
GSList *object_class_get_list(const char *implements_type, |
714 |
bool include_abstract);
|
715 |
|
716 |
/**
|
717 |
* object_ref:
|
718 |
* @obj: the object
|
719 |
*
|
720 |
* Increase the reference count of a object. A object cannot be freed as long
|
721 |
* as its reference count is greater than zero.
|
722 |
*/
|
723 |
void object_ref(Object *obj);
|
724 |
|
725 |
/**
|
726 |
* qdef_unref:
|
727 |
* @obj: the object
|
728 |
*
|
729 |
* Decrease the reference count of a object. A object cannot be freed as long
|
730 |
* as its reference count is greater than zero.
|
731 |
*/
|
732 |
void object_unref(Object *obj);
|
733 |
|
734 |
/**
|
735 |
* object_property_add:
|
736 |
* @obj: the object to add a property to
|
737 |
* @name: the name of the property. This can contain any character except for
|
738 |
* a forward slash. In general, you should use hyphens '-' instead of
|
739 |
* underscores '_' when naming properties.
|
740 |
* @type: the type name of the property. This namespace is pretty loosely
|
741 |
* defined. Sub namespaces are constructed by using a prefix and then
|
742 |
* to angle brackets. For instance, the type 'virtio-net-pci' in the
|
743 |
* 'link' namespace would be 'link<virtio-net-pci>'.
|
744 |
* @get: The getter to be called to read a property. If this is NULL, then
|
745 |
* the property cannot be read.
|
746 |
* @set: the setter to be called to write a property. If this is NULL,
|
747 |
* then the property cannot be written.
|
748 |
* @release: called when the property is removed from the object. This is
|
749 |
* meant to allow a property to free its opaque upon object
|
750 |
* destruction. This may be NULL.
|
751 |
* @opaque: an opaque pointer to pass to the callbacks for the property
|
752 |
* @errp: returns an error if this function fails
|
753 |
*/
|
754 |
void object_property_add(Object *obj, const char *name, const char *type, |
755 |
ObjectPropertyAccessor *get, |
756 |
ObjectPropertyAccessor *set, |
757 |
ObjectPropertyRelease *release, |
758 |
void *opaque, struct Error **errp); |
759 |
|
760 |
void object_property_del(Object *obj, const char *name, struct Error **errp); |
761 |
|
762 |
/**
|
763 |
* object_property_find:
|
764 |
* @obj: the object
|
765 |
* @name: the name of the property
|
766 |
* @errp: returns an error if this function fails
|
767 |
*
|
768 |
* Look up a property for an object and return its #ObjectProperty if found.
|
769 |
*/
|
770 |
ObjectProperty *object_property_find(Object *obj, const char *name, |
771 |
struct Error **errp);
|
772 |
|
773 |
void object_unparent(Object *obj);
|
774 |
|
775 |
/**
|
776 |
* object_property_get:
|
777 |
* @obj: the object
|
778 |
* @v: the visitor that will receive the property value. This should be an
|
779 |
* Output visitor and the data will be written with @name as the name.
|
780 |
* @name: the name of the property
|
781 |
* @errp: returns an error if this function fails
|
782 |
*
|
783 |
* Reads a property from a object.
|
784 |
*/
|
785 |
void object_property_get(Object *obj, struct Visitor *v, const char *name, |
786 |
struct Error **errp);
|
787 |
|
788 |
/**
|
789 |
* object_property_set_str:
|
790 |
* @value: the value to be written to the property
|
791 |
* @name: the name of the property
|
792 |
* @errp: returns an error if this function fails
|
793 |
*
|
794 |
* Writes a string value to a property.
|
795 |
*/
|
796 |
void object_property_set_str(Object *obj, const char *value, |
797 |
const char *name, struct Error **errp); |
798 |
|
799 |
/**
|
800 |
* object_property_get_str:
|
801 |
* @obj: the object
|
802 |
* @name: the name of the property
|
803 |
* @errp: returns an error if this function fails
|
804 |
*
|
805 |
* Returns: the value of the property, converted to a C string, or NULL if
|
806 |
* an error occurs (including when the property value is not a string).
|
807 |
* The caller should free the string.
|
808 |
*/
|
809 |
char *object_property_get_str(Object *obj, const char *name, |
810 |
struct Error **errp);
|
811 |
|
812 |
/**
|
813 |
* object_property_set_link:
|
814 |
* @value: the value to be written to the property
|
815 |
* @name: the name of the property
|
816 |
* @errp: returns an error if this function fails
|
817 |
*
|
818 |
* Writes an object's canonical path to a property.
|
819 |
*/
|
820 |
void object_property_set_link(Object *obj, Object *value,
|
821 |
const char *name, struct Error **errp); |
822 |
|
823 |
/**
|
824 |
* object_property_get_link:
|
825 |
* @obj: the object
|
826 |
* @name: the name of the property
|
827 |
* @errp: returns an error if this function fails
|
828 |
*
|
829 |
* Returns: the value of the property, resolved from a path to an Object,
|
830 |
* or NULL if an error occurs (including when the property value is not a
|
831 |
* string or not a valid object path).
|
832 |
*/
|
833 |
Object *object_property_get_link(Object *obj, const char *name, |
834 |
struct Error **errp);
|
835 |
|
836 |
/**
|
837 |
* object_property_set_bool:
|
838 |
* @value: the value to be written to the property
|
839 |
* @name: the name of the property
|
840 |
* @errp: returns an error if this function fails
|
841 |
*
|
842 |
* Writes a bool value to a property.
|
843 |
*/
|
844 |
void object_property_set_bool(Object *obj, bool value, |
845 |
const char *name, struct Error **errp); |
846 |
|
847 |
/**
|
848 |
* object_property_get_bool:
|
849 |
* @obj: the object
|
850 |
* @name: the name of the property
|
851 |
* @errp: returns an error if this function fails
|
852 |
*
|
853 |
* Returns: the value of the property, converted to a boolean, or NULL if
|
854 |
* an error occurs (including when the property value is not a bool).
|
855 |
*/
|
856 |
bool object_property_get_bool(Object *obj, const char *name, |
857 |
struct Error **errp);
|
858 |
|
859 |
/**
|
860 |
* object_property_set_int:
|
861 |
* @value: the value to be written to the property
|
862 |
* @name: the name of the property
|
863 |
* @errp: returns an error if this function fails
|
864 |
*
|
865 |
* Writes an integer value to a property.
|
866 |
*/
|
867 |
void object_property_set_int(Object *obj, int64_t value,
|
868 |
const char *name, struct Error **errp); |
869 |
|
870 |
/**
|
871 |
* object_property_get_int:
|
872 |
* @obj: the object
|
873 |
* @name: the name of the property
|
874 |
* @errp: returns an error if this function fails
|
875 |
*
|
876 |
* Returns: the value of the property, converted to an integer, or NULL if
|
877 |
* an error occurs (including when the property value is not an integer).
|
878 |
*/
|
879 |
int64_t object_property_get_int(Object *obj, const char *name, |
880 |
struct Error **errp);
|
881 |
|
882 |
/**
|
883 |
* object_property_set:
|
884 |
* @obj: the object
|
885 |
* @v: the visitor that will be used to write the property value. This should
|
886 |
* be an Input visitor and the data will be first read with @name as the
|
887 |
* name and then written as the property value.
|
888 |
* @name: the name of the property
|
889 |
* @errp: returns an error if this function fails
|
890 |
*
|
891 |
* Writes a property to a object.
|
892 |
*/
|
893 |
void object_property_set(Object *obj, struct Visitor *v, const char *name, |
894 |
struct Error **errp);
|
895 |
|
896 |
/**
|
897 |
* object_property_parse:
|
898 |
* @obj: the object
|
899 |
* @string: the string that will be used to parse the property value.
|
900 |
* @name: the name of the property
|
901 |
* @errp: returns an error if this function fails
|
902 |
*
|
903 |
* Parses a string and writes the result into a property of an object.
|
904 |
*/
|
905 |
void object_property_parse(Object *obj, const char *string, |
906 |
const char *name, struct Error **errp); |
907 |
|
908 |
/**
|
909 |
* object_property_print:
|
910 |
* @obj: the object
|
911 |
* @name: the name of the property
|
912 |
* @errp: returns an error if this function fails
|
913 |
*
|
914 |
* Returns a string representation of the value of the property. The
|
915 |
* caller shall free the string.
|
916 |
*/
|
917 |
char *object_property_print(Object *obj, const char *name, |
918 |
struct Error **errp);
|
919 |
|
920 |
/**
|
921 |
* object_property_get_type:
|
922 |
* @obj: the object
|
923 |
* @name: the name of the property
|
924 |
* @errp: returns an error if this function fails
|
925 |
*
|
926 |
* Returns: The type name of the property.
|
927 |
*/
|
928 |
const char *object_property_get_type(Object *obj, const char *name, |
929 |
struct Error **errp);
|
930 |
|
931 |
/**
|
932 |
* object_get_root:
|
933 |
*
|
934 |
* Returns: the root object of the composition tree
|
935 |
*/
|
936 |
Object *object_get_root(void);
|
937 |
|
938 |
/**
|
939 |
* object_get_canonical_path:
|
940 |
*
|
941 |
* Returns: The canonical path for a object. This is the path within the
|
942 |
* composition tree starting from the root.
|
943 |
*/
|
944 |
gchar *object_get_canonical_path(Object *obj); |
945 |
|
946 |
/**
|
947 |
* object_resolve_path:
|
948 |
* @path: the path to resolve
|
949 |
* @ambiguous: returns true if the path resolution failed because of an
|
950 |
* ambiguous match
|
951 |
*
|
952 |
* There are two types of supported paths--absolute paths and partial paths.
|
953 |
*
|
954 |
* Absolute paths are derived from the root object and can follow child<> or
|
955 |
* link<> properties. Since they can follow link<> properties, they can be
|
956 |
* arbitrarily long. Absolute paths look like absolute filenames and are
|
957 |
* prefixed with a leading slash.
|
958 |
*
|
959 |
* Partial paths look like relative filenames. They do not begin with a
|
960 |
* prefix. The matching rules for partial paths are subtle but designed to make
|
961 |
* specifying objects easy. At each level of the composition tree, the partial
|
962 |
* path is matched as an absolute path. The first match is not returned. At
|
963 |
* least two matches are searched for. A successful result is only returned if
|
964 |
* only one match is found. If more than one match is found, a flag is
|
965 |
* returned to indicate that the match was ambiguous.
|
966 |
*
|
967 |
* Returns: The matched object or NULL on path lookup failure.
|
968 |
*/
|
969 |
Object *object_resolve_path(const char *path, bool *ambiguous); |
970 |
|
971 |
/**
|
972 |
* object_resolve_path_type:
|
973 |
* @path: the path to resolve
|
974 |
* @typename: the type to look for.
|
975 |
* @ambiguous: returns true if the path resolution failed because of an
|
976 |
* ambiguous match
|
977 |
*
|
978 |
* This is similar to object_resolve_path. However, when looking for a
|
979 |
* partial path only matches that implement the given type are considered.
|
980 |
* This restricts the search and avoids spuriously flagging matches as
|
981 |
* ambiguous.
|
982 |
*
|
983 |
* For both partial and absolute paths, the return value goes through
|
984 |
* a dynamic cast to @typename. This is important if either the link,
|
985 |
* or the typename itself are of interface types.
|
986 |
*
|
987 |
* Returns: The matched object or NULL on path lookup failure.
|
988 |
*/
|
989 |
Object *object_resolve_path_type(const char *path, const char *typename, |
990 |
bool *ambiguous);
|
991 |
|
992 |
/**
|
993 |
* object_resolve_path_component:
|
994 |
* @parent: the object in which to resolve the path
|
995 |
* @part: the component to resolve.
|
996 |
*
|
997 |
* This is similar to object_resolve_path with an absolute path, but it
|
998 |
* only resolves one element (@part) and takes the others from @parent.
|
999 |
*
|
1000 |
* Returns: The resolved object or NULL on path lookup failure.
|
1001 |
*/
|
1002 |
Object *object_resolve_path_component(Object *parent, const gchar *part);
|
1003 |
|
1004 |
/**
|
1005 |
* object_property_add_child:
|
1006 |
* @obj: the object to add a property to
|
1007 |
* @name: the name of the property
|
1008 |
* @child: the child object
|
1009 |
* @errp: if an error occurs, a pointer to an area to store the area
|
1010 |
*
|
1011 |
* Child properties form the composition tree. All objects need to be a child
|
1012 |
* of another object. Objects can only be a child of one object.
|
1013 |
*
|
1014 |
* There is no way for a child to determine what its parent is. It is not
|
1015 |
* a bidirectional relationship. This is by design.
|
1016 |
*
|
1017 |
* The value of a child property as a C string will be the child object's
|
1018 |
* canonical path. It can be retrieved using object_property_get_str().
|
1019 |
* The child object itself can be retrieved using object_property_get_link().
|
1020 |
*/
|
1021 |
void object_property_add_child(Object *obj, const char *name, |
1022 |
Object *child, struct Error **errp);
|
1023 |
|
1024 |
/**
|
1025 |
* object_property_add_link:
|
1026 |
* @obj: the object to add a property to
|
1027 |
* @name: the name of the property
|
1028 |
* @type: the qobj type of the link
|
1029 |
* @child: a pointer to where the link object reference is stored
|
1030 |
* @errp: if an error occurs, a pointer to an area to store the area
|
1031 |
*
|
1032 |
* Links establish relationships between objects. Links are unidirectional
|
1033 |
* although two links can be combined to form a bidirectional relationship
|
1034 |
* between objects.
|
1035 |
*
|
1036 |
* Links form the graph in the object model.
|
1037 |
*
|
1038 |
* Ownership of the pointer that @child points to is transferred to the
|
1039 |
* link property. The reference count for <code>*@child</code> is
|
1040 |
* managed by the property from after the function returns till the
|
1041 |
* property is deleted with object_property_del().
|
1042 |
*/
|
1043 |
void object_property_add_link(Object *obj, const char *name, |
1044 |
const char *type, Object **child, |
1045 |
struct Error **errp);
|
1046 |
|
1047 |
/**
|
1048 |
* object_property_add_str:
|
1049 |
* @obj: the object to add a property to
|
1050 |
* @name: the name of the property
|
1051 |
* @get: the getter or NULL if the property is write-only. This function must
|
1052 |
* return a string to be freed by g_free().
|
1053 |
* @set: the setter or NULL if the property is read-only
|
1054 |
* @errp: if an error occurs, a pointer to an area to store the error
|
1055 |
*
|
1056 |
* Add a string property using getters/setters. This function will add a
|
1057 |
* property of type 'string'.
|
1058 |
*/
|
1059 |
void object_property_add_str(Object *obj, const char *name, |
1060 |
char *(*get)(Object *, struct Error **), |
1061 |
void (*set)(Object *, const char *, struct Error **), |
1062 |
struct Error **errp);
|
1063 |
|
1064 |
/**
|
1065 |
* object_property_add_bool:
|
1066 |
* @obj: the object to add a property to
|
1067 |
* @name: the name of the property
|
1068 |
* @get: the getter or NULL if the property is write-only.
|
1069 |
* @set: the setter or NULL if the property is read-only
|
1070 |
* @errp: if an error occurs, a pointer to an area to store the error
|
1071 |
*
|
1072 |
* Add a bool property using getters/setters. This function will add a
|
1073 |
* property of type 'bool'.
|
1074 |
*/
|
1075 |
void object_property_add_bool(Object *obj, const char *name, |
1076 |
bool (*get)(Object *, struct Error **), |
1077 |
void (*set)(Object *, bool, struct Error **), |
1078 |
struct Error **errp);
|
1079 |
|
1080 |
/**
|
1081 |
* object_child_foreach:
|
1082 |
* @obj: the object whose children will be navigated
|
1083 |
* @fn: the iterator function to be called
|
1084 |
* @opaque: an opaque value that will be passed to the iterator
|
1085 |
*
|
1086 |
* Call @fn passing each child of @obj and @opaque to it, until @fn returns
|
1087 |
* non-zero.
|
1088 |
*
|
1089 |
* Returns: The last value returned by @fn, or 0 if there is no child.
|
1090 |
*/
|
1091 |
int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque), |
1092 |
void *opaque);
|
1093 |
|
1094 |
/**
|
1095 |
* container_get:
|
1096 |
* @root: root of the #path, e.g., object_get_root()
|
1097 |
* @path: path to the container
|
1098 |
*
|
1099 |
* Return a container object whose path is @path. Create more containers
|
1100 |
* along the path if necessary.
|
1101 |
*
|
1102 |
* Returns: the container object.
|
1103 |
*/
|
1104 |
Object *container_get(Object *root, const char *path); |
1105 |
|
1106 |
|
1107 |
#endif
|