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<li class="toctree-l2 current"><a class="current reference internal" href="#">The QEMU Object Model (QOM)</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#class-initialization">Class Initialization</a></li>
<li class="toctree-l3"><a class="reference internal" href="#interfaces">Interfaces</a></li>
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 <div class="section" id="the-qemu-object-model-qom">
<h1>The QEMU Object Model (QOM)<a class="headerlink" href="#the-qemu-object-model-qom" title="Permalink to this headline">¶</a></h1>
The QEMU Object Model provides a framework for registering user creatable
types and instantiating objects from those types. QOM provides the following
features:
<ul class="simple">
<li>System for dynamically registering types</li>
<li>Support for single-inheritance of types</li>
<li>Multiple inheritance of stateless interfaces</li>
</ul>
<div class="literal-block-wrapper docutils container" id="id1">
<div class="code-block-caption">Creating a minimal type<a class="headerlink" href="#id1" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>#include &quot;qdev.h&quot;

#define TYPE_MY_DEVICE &quot;my-device&quot;

// 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(&amp;my_device_info);
}

type_init(my_device_register_types)
</pre></div>
</div>
</div>
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.
Alternatively several static types could be registered using helper macro
DEFINE_TYPES()
<div class="highlight-c notranslate"><div class="highlight"><pre>static const TypeInfo device_types_info[] = {
 {
 .name = TYPE_MY_DEVICE_A,
 .parent = TYPE_DEVICE,
 .instance_size = sizeof(MyDeviceA),
 },
 {
 .name = TYPE_MY_DEVICE_B,
 .parent = TYPE_DEVICE,
 .instance_size = sizeof(MyDeviceB),
 },
};

DEFINE_TYPES(device_types_info)
</pre></div>
</div>
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:
<div class="literal-block-wrapper docutils container" id="id2">
<div class="code-block-caption">Typecasting macros<a class="headerlink" href="#id2" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>#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)
</pre></div>
</div>
</div>
In case the ObjectClass implementation can be built as module a
module_obj() line must be added to make sure qemu loads the module
when the object is needed.
<div class="highlight-c notranslate"><div class="highlight"><pre>module_obj(TYPE_MY_DEVICE);
</pre></div>
</div>
<div class="section" id="class-initialization">
<h2>Class Initialization<a class="headerlink" href="#class-initialization" title="Permalink to this headline">¶</a></h2>
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:
<div class="literal-block-wrapper docutils container" id="id3">
<div class="code-block-caption">Overriding a virtual function<a class="headerlink" href="#id3" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>#include &quot;qdev.h&quot;

void my_device_class_init(ObjectClass *klass, void *class_data)
{
 DeviceClass *dc = DEVICE_CLASS(klass);
 dc-&gt;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,
};
</pre></div>
</div>
</div>
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:
<div class="literal-block-wrapper docutils container" id="id4">
<div class="code-block-caption">Defining an abstract class<a class="headerlink" href="#id4" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>#include &quot;qdev.h&quot;

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-&gt;frobnicate(obj);
}
</pre></div>
</div>
</div>
</div>
<div class="section" id="interfaces">
<h2>Interfaces<a class="headerlink" href="#interfaces" title="Permalink to this headline">¶</a></h2>
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. As a consequence, a pointer to
an interface instance should always be of incomplete type in order to be
sure it cannot be dereferenced. That is, you should define the
‘typedef struct SomethingIf SomethingIf’ so that you can pass around
<code class="docutils literal notranslate">SomethingIf *si</code> arguments, but not define a <code class="docutils literal notranslate">struct SomethingIf { ... }</code>.
The only things you can validly do with a <code class="docutils literal notranslate">SomethingIf *</code> are to pass it as
an argument to a method on its corresponding SomethingIfClass, or to
dynamically cast it to an object that implements the interface.
</div>
<div class="section" id="methods">
<h2>Methods<a class="headerlink" href="#methods" title="Permalink to this headline">¶</a></h2>
A method 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
class method.
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 virtual. 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 <code class="docutils literal notranslate">{super,base}.method(...)</code> in Java and C#
respectively; this frees the overriding class from hardcoding its parent
class, which someone might choose to change at some point.
<div class="literal-block-wrapper docutils container" id="id5">
<div class="code-block-caption">Overriding a virtual method<a class="headerlink" href="#id5" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>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-&gt;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-&gt;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-&gt;parent_do_something = mc-&gt;do_something;
 mc-&gt;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,
};
</pre></div>
</div>
</div>
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
<code class="docutils literal notranslate">MyClass::method(...)</code> in C++.
The first example of such a QOM method was #CPUClass.reset,
another example is #DeviceClass.realize.
</div>
<div class="section" id="standard-type-declaration-and-definition-macros">
<h2>Standard type declaration and definition macros<a class="headerlink" href="#standard-type-declaration-and-definition-macros" title="Permalink to this headline">¶</a></h2>
A lot of the code outlined above follows a standard pattern and naming
convention. To reduce the amount of boilerplate code that needs to be
written for a new type there are two sets of macros to generate the
common parts in a standard format.
A type is declared using the OBJECT_DECLARE macro family. In types
which do not require any virtual functions in the class, the
OBJECT_DECLARE_SIMPLE_TYPE macro is suitable, and is commonly placed
in the header file:
<div class="literal-block-wrapper docutils container" id="id6">
<div class="code-block-caption">Declaring a simple type<a class="headerlink" href="#id6" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>OBJECT_DECLARE_SIMPLE_TYPE(MyDevice, my_device,
 MY_DEVICE, DEVICE)
</pre></div>
</div>
</div>
This is equivalent to the following:
<div class="literal-block-wrapper docutils container" id="id7">
<div class="code-block-caption">Expansion from declaring a simple type<a class="headerlink" href="#id7" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>typedef struct MyDevice MyDevice;
typedef struct MyDeviceClass MyDeviceClass;

G_DEFINE_AUTOPTR_CLEANUP_FUNC(MyDeviceClass, object_unref)

#define MY_DEVICE_GET_CLASS(void *obj) \
 OBJECT_GET_CLASS(MyDeviceClass, obj, TYPE_MY_DEVICE)
#define MY_DEVICE_CLASS(void *klass) \
 OBJECT_CLASS_CHECK(MyDeviceClass, klass, TYPE_MY_DEVICE)
#define MY_DEVICE(void *obj)
 OBJECT_CHECK(MyDevice, obj, TYPE_MY_DEVICE)

struct MyDeviceClass {
 DeviceClass parent_class;
};
</pre></div>
</div>
</div>
The ‘struct MyDevice’ needs to be declared separately.
If the type requires virtual functions to be declared in the class
struct, then the alternative OBJECT_DECLARE_TYPE() macro can be
used. This does the same as OBJECT_DECLARE_SIMPLE_TYPE(), but without
the ‘struct MyDeviceClass’ definition.
To implement the type, the OBJECT_DEFINE macro family is available.
In the simple case the OBJECT_DEFINE_TYPE macro is suitable:
<div class="literal-block-wrapper docutils container" id="id8">
<div class="code-block-caption">Defining a simple type<a class="headerlink" href="#id8" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>OBJECT_DEFINE_TYPE(MyDevice, my_device, MY_DEVICE, DEVICE)
</pre></div>
</div>
</div>
This is equivalent to the following:
<div class="literal-block-wrapper docutils container" id="id9">
<div class="code-block-caption">Expansion from defining a simple type<a class="headerlink" href="#id9" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>static void my_device_finalize(Object *obj);
static void my_device_class_init(ObjectClass *oc, void *data);
static void my_device_init(Object *obj);

static const TypeInfo my_device_info = {
 .parent = TYPE_DEVICE,
 .name = TYPE_MY_DEVICE,
 .instance_size = sizeof(MyDevice),
 .instance_init = my_device_init,
 .instance_finalize = my_device_finalize,
 .class_size = sizeof(MyDeviceClass),
 .class_init = my_device_class_init,
};

static void
my_device_register_types(void)
{
 type_register_static(&amp;my_device_info);
}
type_init(my_device_register_types);
</pre></div>
</div>
</div>
This is sufficient to get the type registered with the type
system, and the three standard methods now need to be implemented
along with any other logic required for the type.
If the type needs to implement one or more interfaces, then the
OBJECT_DEFINE_TYPE_WITH_INTERFACES() macro can be used instead.
This accepts an array of interface type names.
<div class="literal-block-wrapper docutils container" id="id10">
<div class="code-block-caption">Defining a simple type implementing interfaces<a class="headerlink" href="#id10" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>OBJECT_DEFINE_TYPE_WITH_INTERFACES(MyDevice, my_device,
 MY_DEVICE, DEVICE,
 { TYPE_USER_CREATABLE },
 { NULL })
</pre></div>
</div>
</div>
If the type is not intended to be instantiated, then then
the OBJECT_DEFINE_ABSTRACT_TYPE() macro can be used instead:
<div class="literal-block-wrapper docutils container" id="id11">
<div class="code-block-caption">Defining a simple abstract type<a class="headerlink" href="#id11" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre>OBJECT_DEFINE_ABSTRACT_TYPE(MyDevice, my_device,
 MY_DEVICE, DEVICE)
</pre></div>
</div>
</div>
<div class="section" id="api-reference">
<h3>API Reference<a class="headerlink" href="#api-reference" title="Permalink to this headline">¶</a></h3>
<dl class="type">
<dt id="c.ObjectPropertyAccessor">
<code class="descname">ObjectPropertyAccessor</code><a class="headerlink" href="#c.ObjectPropertyAccessor" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">void ObjectPropertyAccessor (Object *obj, Visitor *v, const char *name, void *opaque, Error **errp)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object that owns the property</dd>
<dt><code class="docutils literal notranslate">Visitor *v</code></dt>
<dd>the visitor that contains the property data</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>the object property opaque</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>a pointer to an Error that is filled if getting/setting fails.</dd>
</dl>
Description
Called when trying to get/set a property.
<dl class="type">
<dt id="c.ObjectPropertyResolve">
<code class="descname">ObjectPropertyResolve</code><a class="headerlink" href="#c.ObjectPropertyResolve" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">Object * ObjectPropertyResolve (Object *obj, void *opaque, const char *part)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object that owns the property</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>the opaque registered with the property</dd>
<dt><code class="docutils literal notranslate">const char *part</code></dt>
<dd>the name of the property</dd>
</dl>
Description
Resolves the <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a> corresponding to property part.
The returned object can also be used as a starting point
to resolve a relative path starting with “part”.
Return
If path is the path that led to obj, the function
returns the <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a> corresponding to “path/part”.
If “path/part” is not a valid object path, it returns <code class="xref c c-type docutils literal notranslate">NULL</code>.
<dl class="type">
<dt id="c.ObjectPropertyRelease">
<code class="descname">ObjectPropertyRelease</code><a class="headerlink" href="#c.ObjectPropertyRelease" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">void ObjectPropertyRelease (Object *obj, const char *name, void *opaque)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object that owns the property</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>the opaque registered with the property</dd>
</dl>
Description
Called when a property is removed from a object.
<dl class="type">
<dt id="c.ObjectPropertyInit">
<code class="descname">ObjectPropertyInit</code><a class="headerlink" href="#c.ObjectPropertyInit" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">void ObjectPropertyInit (Object *obj, ObjectProperty *prop)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object that owns the property</dd>
<dt><code class="docutils literal notranslate">ObjectProperty *prop</code></dt>
<dd>the property to set</dd>
</dl>
Description
Called when a property is initialized.
<dl class="type">
<dt id="c.ObjectUnparent">
<code class="descname">ObjectUnparent</code><a class="headerlink" href="#c.ObjectUnparent" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">void ObjectUnparent (Object *obj)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object that is being removed from the composition tree</dd>
</dl>
Description
Called when an object is being removed from the QOM composition tree.
The function should remove any backlinks from children objects to obj.
<dl class="type">
<dt id="c.ObjectFree">
<code class="descname">ObjectFree</code><a class="headerlink" href="#c.ObjectFree" title="Permalink to this definition">¶</a></dt>
<dd>Typedef:
</dd></dl>

Syntax
<blockquote>
<div><code class="docutils literal notranslate">void ObjectFree (void *obj)</code></div></blockquote>
Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void *obj</code></dt>
<dd>the object being freed</dd>
</dl>
Description
Called when an object’s last reference is removed.
<dl class="type">
<dt id="c.ObjectClass">
struct <code class="descname">ObjectClass</code><a class="headerlink" href="#c.ObjectClass" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Definition
<div class="highlight-c notranslate"><div class="highlight"><pre>struct ObjectClass {
};
</pre></div>
</div>
Members
Description
The base for all classes. The only thing that <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a> contains is an
integer type handle.
<dl class="type">
<dt id="c.Object">
struct <code class="descname">Object</code><a class="headerlink" href="#c.Object" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Definition
<div class="highlight-c notranslate"><div class="highlight"><pre>struct Object {
};
</pre></div>
</div>
Members
Description
The base for all objects. The first member of this object is a pointer to
a <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a>. 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 <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a>.
As a result, <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a> contains a reference to the objects type as its
first member. This allows identification of the real type of the object at
run time.
<dl class="function">
<dt id="c.DECLARE_INSTANCE_CHECKER">
<code class="descname">DECLARE_INSTANCE_CHECKER</code>(InstanceType, OBJ_NAME, TYPENAME)<a class="headerlink" href="#c.DECLARE_INSTANCE_CHECKER" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">InstanceType</code></dt>
<dd>instance struct name</dd>
<dt><code class="docutils literal notranslate">OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">TYPENAME</code></dt>
<dd>type name</dd>
</dl>
Description
Direct usage of this macro should be avoided, and the complete
OBJECT_DECLARE_TYPE macro is recommended instead.
This macro will provide the instance type cast functions for a
QOM type.
<dl class="function">
<dt id="c.DECLARE_CLASS_CHECKERS">
<code class="descname">DECLARE_CLASS_CHECKERS</code>(ClassType, OBJ_NAME, TYPENAME)<a class="headerlink" href="#c.DECLARE_CLASS_CHECKERS" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ClassType</code></dt>
<dd>class struct name</dd>
<dt><code class="docutils literal notranslate">OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">TYPENAME</code></dt>
<dd>type name</dd>
</dl>
Description
Direct usage of this macro should be avoided, and the complete
OBJECT_DECLARE_TYPE macro is recommended instead.
This macro will provide the class type cast functions for a
QOM type.
<dl class="function">
<dt id="c.DECLARE_OBJ_CHECKERS">
<code class="descname">DECLARE_OBJ_CHECKERS</code>(InstanceType, ClassType, OBJ_NAME, TYPENAME)<a class="headerlink" href="#c.DECLARE_OBJ_CHECKERS" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">InstanceType</code></dt>
<dd>instance struct name</dd>
<dt><code class="docutils literal notranslate">ClassType</code></dt>
<dd>class struct name</dd>
<dt><code class="docutils literal notranslate">OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">TYPENAME</code></dt>
<dd>type name</dd>
</dl>
Description
Direct usage of this macro should be avoided, and the complete
OBJECT_DECLARE_TYPE macro is recommended instead.
This macro will provide the three standard type cast functions for a
QOM type.
<dl class="function">
<dt id="c.OBJECT_DECLARE_TYPE">
<code class="descname">OBJECT_DECLARE_TYPE</code>(InstanceType, ClassType, MODULE_OBJ_NAME)<a class="headerlink" href="#c.OBJECT_DECLARE_TYPE" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">InstanceType</code></dt>
<dd>instance struct name</dd>
<dt><code class="docutils literal notranslate">ClassType</code></dt>
<dd>class struct name</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
</dl>
Description
This macro is typically used in a header file, and will:
<blockquote>
<div><ul class="simple">
<li>create the typedefs for the object and class structs</li>
<li>register the type for use with g_autoptr</li>
<li>provide three standard type cast functions</li>
</ul>
</div></blockquote>
The object struct and class struct need to be declared manually.
<dl class="function">
<dt id="c.OBJECT_DECLARE_SIMPLE_TYPE">
<code class="descname">OBJECT_DECLARE_SIMPLE_TYPE</code>(InstanceType, MODULE_OBJ_NAME)<a class="headerlink" href="#c.OBJECT_DECLARE_SIMPLE_TYPE" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">InstanceType</code></dt>
<dd>instance struct name</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
</dl>
Description
This does the same as OBJECT_DECLARE_TYPE(), but with no class struct
declared.
This macro should be used unless the class struct needs to have
virtual methods declared.
<dl class="function">
<dt id="c.OBJECT_DEFINE_TYPE_EXTENDED">
<code class="descname">OBJECT_DEFINE_TYPE_EXTENDED</code>(ModuleObjName, module_obj_name, MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, ABSTRACT, ...)<a class="headerlink" href="#c.OBJECT_DEFINE_TYPE_EXTENDED" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ModuleObjName</code></dt>
<dd>the object name with initial caps</dd>
<dt><code class="docutils literal notranslate">module_obj_name</code></dt>
<dd>the object name in lowercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">PARENT_MODULE_OBJ_NAME</code></dt>
<dd>the parent object name in uppercase with underscore
separators</dd>
<dt><code class="docutils literal notranslate">ABSTRACT</code></dt>
<dd>boolean flag to indicate whether the object can be instantiated</dd>
<dt><code class="docutils literal notranslate">...</code></dt>
<dd>list of initializers for “InterfaceInfo” to declare implemented interfaces</dd>
</dl>
Description
This macro is typically used in a source file, and will:
<blockquote>
<div><ul class="simple">
<li>declare prototypes for _finalize, _class_init and _init methods</li>
<li>declare the TypeInfo struct instance</li>
<li>provide the constructor to register the type</li>
</ul>
</div></blockquote>
After using this macro, implementations of the _finalize, _class_init,
and _init methods need to be written. Any of these can be zero-line
no-op impls if no special logic is required for a given type.
This macro should rarely be used, instead one of the more specialized
macros is usually a better choice.
<dl class="function">
<dt id="c.OBJECT_DEFINE_TYPE">
<code class="descname">OBJECT_DEFINE_TYPE</code>(ModuleObjName, module_obj_name, MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME)<a class="headerlink" href="#c.OBJECT_DEFINE_TYPE" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ModuleObjName</code></dt>
<dd>the object name with initial caps</dd>
<dt><code class="docutils literal notranslate">module_obj_name</code></dt>
<dd>the object name in lowercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">PARENT_MODULE_OBJ_NAME</code></dt>
<dd>the parent object name in uppercase with underscore
separators</dd>
</dl>
Description
This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
for the common case of a non-abstract type, without any interfaces.
<dl class="function">
<dt id="c.OBJECT_DEFINE_TYPE_WITH_INTERFACES">
<code class="descname">OBJECT_DEFINE_TYPE_WITH_INTERFACES</code>(ModuleObjName, module_obj_name, MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, ...)<a class="headerlink" href="#c.OBJECT_DEFINE_TYPE_WITH_INTERFACES" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ModuleObjName</code></dt>
<dd>the object name with initial caps</dd>
<dt><code class="docutils literal notranslate">module_obj_name</code></dt>
<dd>the object name in lowercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">PARENT_MODULE_OBJ_NAME</code></dt>
<dd>the parent object name in uppercase with underscore
separators</dd>
<dt><code class="docutils literal notranslate">...</code></dt>
<dd>list of initializers for “InterfaceInfo” to declare implemented interfaces</dd>
</dl>
Description
This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
for the common case of a non-abstract type, with one or more implemented
interfaces.
Note when passing the list of interfaces, be sure to include the final
NULL entry, e.g. { TYPE_USER_CREATABLE }, { NULL }
<dl class="function">
<dt id="c.OBJECT_DEFINE_ABSTRACT_TYPE">
<code class="descname">OBJECT_DEFINE_ABSTRACT_TYPE</code>(ModuleObjName, module_obj_name, MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME)<a class="headerlink" href="#c.OBJECT_DEFINE_ABSTRACT_TYPE" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ModuleObjName</code></dt>
<dd>the object name with initial caps</dd>
<dt><code class="docutils literal notranslate">module_obj_name</code></dt>
<dd>the object name in lowercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">MODULE_OBJ_NAME</code></dt>
<dd>the object name in uppercase with underscore separators</dd>
<dt><code class="docutils literal notranslate">PARENT_MODULE_OBJ_NAME</code></dt>
<dd>the parent object name in uppercase with underscore
separators</dd>
</dl>
Description
This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
for defining an abstract type, without any interfaces.
<dl class="type">
<dt id="c.TypeInfo">
struct <code class="descname">TypeInfo</code><a class="headerlink" href="#c.TypeInfo" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Definition
<div class="highlight-c notranslate"><div class="highlight"><pre>struct TypeInfo {
 const char *name;
 const char *parent;
 size_t instance_size;
 size_t instance_align;
 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_data;
 InterfaceInfo *interfaces;
};
</pre></div>
</div>
Members
<dl class="docutils">
<dt><code class="docutils literal notranslate">name</code></dt>
<dd>The name of the type.</dd>
<dt><code class="docutils literal notranslate">parent</code></dt>
<dd>The name of the parent type.</dd>
<dt><code class="docutils literal notranslate">instance_size</code></dt>
<dd>The size of the object (derivative of <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a>). If
instance_size is 0, then the size of the object will be the size of the
parent object.</dd>
<dt><code class="docutils literal notranslate">instance_align</code></dt>
<dd>The required alignment of the object. If instance_align
is 0, then normal malloc alignment is sufficient; if non-zero, then we
must use qemu_memalign for allocation.</dd>
<dt><code class="docutils literal notranslate">instance_init</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">instance_post_init</code></dt>
<dd>This function is called to finish initialization of
an object, after all instance_init functions were called.</dd>
<dt><code class="docutils literal notranslate">instance_finalize</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">abstract</code></dt>
<dd>If this field is true, then the class is considered abstract and
cannot be directly instantiated.</dd>
<dt><code class="docutils literal notranslate">class_size</code></dt>
<dd>The size of the class object (derivative of <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a>)
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.</dd>
<dt><code class="docutils literal notranslate">class_init</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">class_base_init</code></dt>
<dd>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 descendants.</dd>
<dt><code class="docutils literal notranslate">class_data</code></dt>
<dd>Data to pass to the class_init,
class_base_init. This can be useful when building dynamic
classes.</dd>
<dt><code class="docutils literal notranslate">interfaces</code></dt>
<dd>The list of interfaces associated with this type. This
should point to a static array that’s terminated with a zero filled
element.</dd>
</dl>
<dl class="function">
<dt id="c.OBJECT">
<code class="descname">OBJECT</code>(obj)<a class="headerlink" href="#c.OBJECT" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">obj</code></dt>
<dd>A derivative of <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a></dd>
</dl>
Description
Converts an object to a <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a>. Since all objects are <code class="xref c c-type docutils literal notranslate">Objects</code>,
this function will always succeed.
<dl class="function">
<dt id="c.OBJECT_CLASS">
<code class="descname">OBJECT_CLASS</code>(class)<a class="headerlink" href="#c.OBJECT_CLASS" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">class</code></dt>
<dd>A derivative of <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a>.</dd>
</dl>
Description
Converts a class to an <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a>. Since all objects are <code class="xref c c-type docutils literal notranslate">Objects</code>,
this function will always succeed.
<dl class="function">
<dt id="c.OBJECT_CHECK">
<code class="descname">OBJECT_CHECK</code>(type, obj, name)<a class="headerlink" href="#c.OBJECT_CHECK" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">type</code></dt>
<dd>The C type to use for the return value.</dd>
<dt><code class="docutils literal notranslate">obj</code></dt>
<dd>A derivative of type to cast.</dd>
<dt><code class="docutils literal notranslate">name</code></dt>
<dd>The QOM typename of type</dd>
</dl>
Description
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.
<dl class="function">
<dt id="c.OBJECT_CLASS_CHECK">
<code class="descname">OBJECT_CLASS_CHECK</code>(class_type, class, name)<a class="headerlink" href="#c.OBJECT_CLASS_CHECK" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">class_type</code></dt>
<dd>The C type to use for the return value.</dd>
<dt><code class="docutils literal notranslate">class</code></dt>
<dd>A derivative class of class_type to cast.</dd>
<dt><code class="docutils literal notranslate">name</code></dt>
<dd>the QOM typename of class_type.</dd>
</dl>
Description
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.
<dl class="function">
<dt id="c.OBJECT_GET_CLASS">
<code class="descname">OBJECT_GET_CLASS</code>(class, obj, name)<a class="headerlink" href="#c.OBJECT_GET_CLASS" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">class</code></dt>
<dd>The C type to use for the return value.</dd>
<dt><code class="docutils literal notranslate">obj</code></dt>
<dd>The object to obtain the class for.</dd>
<dt><code class="docutils literal notranslate">name</code></dt>
<dd>The QOM typename of obj.</dd>
</dl>
Description
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.
<dl class="type">
<dt id="c.InterfaceInfo">
struct <code class="descname">InterfaceInfo</code><a class="headerlink" href="#c.InterfaceInfo" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Definition
<div class="highlight-c notranslate"><div class="highlight"><pre>struct InterfaceInfo {
 const char *type;
};
</pre></div>
</div>
Members
<dl class="docutils">
<dt><code class="docutils literal notranslate">type</code></dt>
<dd>The name of the interface.</dd>
</dl>
Description
The information associated with an interface.
<dl class="type">
<dt id="c.InterfaceClass">
struct <code class="descname">InterfaceClass</code><a class="headerlink" href="#c.InterfaceClass" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Definition
<div class="highlight-c notranslate"><div class="highlight"><pre>struct InterfaceClass {
 ObjectClass parent_class;
};
</pre></div>
</div>
Members
<dl class="docutils">
<dt><code class="docutils literal notranslate">parent_class</code></dt>
<dd>the base class</dd>
</dl>
Description
The class for all interfaces. Subclasses of this class should only add
virtual methods.
<dl class="function">
<dt id="c.INTERFACE_CLASS">
<code class="descname">INTERFACE_CLASS</code>(klass)<a class="headerlink" href="#c.INTERFACE_CLASS" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">klass</code></dt>
<dd>class to cast from</dd>
</dl>
Return
An <a class="reference internal" href="#c.InterfaceClass" title="InterfaceClass"><code class="xref c c-type docutils literal notranslate">InterfaceClass</code></a> or raise an error if cast is invalid
<dl class="function">
<dt id="c.INTERFACE_CHECK">
<code class="descname">INTERFACE_CHECK</code>(interface, obj, name)<a class="headerlink" href="#c.INTERFACE_CHECK" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">interface</code></dt>
<dd>the type to return</dd>
<dt><code class="docutils literal notranslate">obj</code></dt>
<dd>the object to convert to an interface</dd>
<dt><code class="docutils literal notranslate">name</code></dt>
<dd>the interface type name</dd>
</dl>
Return
obj casted to interface if cast is valid, otherwise raise error.
<dl class="function">
<dt id="c.object_new_with_class">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_new_with_class</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass)<a class="headerlink" href="#c.object_new_with_class" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The class to instantiate.</dd>
</dl>
Description
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.
Return
The newly allocated and instantiated object.
<dl class="function">
<dt id="c.object_new">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_new</code>(const char&nbsp;*typename)<a class="headerlink" href="#c.object_new" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
</dl>
Description
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.
Return
The newly allocated and instantiated object.
<dl class="function">
<dt id="c.object_new_with_props">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_new_with_props</code>(const char&nbsp;*typename, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parent, const char&nbsp;*id, Error&nbsp;**errp, ...)<a class="headerlink" href="#c.object_new_with_props" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
<dt><code class="docutils literal notranslate">Object *parent</code></dt>
<dd>the parent object</dd>
<dt><code class="docutils literal notranslate">const char *id</code></dt>
<dd>The unique ID of the object</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
<dt><code class="docutils literal notranslate">...</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
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 <code class="docutils literal notranslate">NULL</code> 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.
<div class="literal-block-wrapper docutils container" id="id12">
<div class="code-block-caption">Creating an object with properties<a class="headerlink" href="#id12" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre> Error *err = NULL;
 Object *obj;

obj = object_new_with_props(TYPE_MEMORY_BACKEND_FILE,
 object_get_objects_root(),
 &quot;hostmem0&quot;,
 &amp;err,
 &quot;share&quot;, &quot;yes&quot;,
 &quot;mem-path&quot;, &quot;/dev/shm/somefile&quot;,
 &quot;prealloc&quot;, &quot;yes&quot;,
 &quot;size&quot;, &quot;1048576&quot;,
 NULL);

if (!obj) {
 error_reportf_err(err, &quot;Cannot create memory backend: &quot;);
 }
</pre></div>
</div>
</div>
The returned object will have one stable reference maintained
for as long as it is present in the object hierarchy.
Return
The newly allocated, instantiated &amp; initialized object.
<dl class="function">
<dt id="c.object_new_with_propv">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_new_with_propv</code>(const char&nbsp;*typename, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parent, const char&nbsp;*id, Error&nbsp;**errp, va_list&nbsp;vargs)<a class="headerlink" href="#c.object_new_with_propv" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
<dt><code class="docutils literal notranslate">Object *parent</code></dt>
<dd>the parent object</dd>
<dt><code class="docutils literal notranslate">const char *id</code></dt>
<dd>The unique ID of the object</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
<dt><code class="docutils literal notranslate">va_list vargs</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
See object_new_with_props() for documentation.
<dl class="function">
<dt id="c.object_set_props">
bool <code class="descname">object_set_props</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, Error&nbsp;**errp, ...)<a class="headerlink" href="#c.object_set_props" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object instance to set properties on</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
<dt><code class="docutils literal notranslate">...</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
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 <code class="docutils literal notranslate">NULL</code> indicates the end of the property
list.
<div class="literal-block-wrapper docutils container" id="id13">
<div class="code-block-caption">Update an object’s properties<a class="headerlink" href="#id13" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre> Error *err = NULL;
 Object *obj = ...get / create object...;

if (!object_set_props(obj,
 &amp;err,
 &quot;share&quot;, &quot;yes&quot;,
 &quot;mem-path&quot;, &quot;/dev/shm/somefile&quot;,
 &quot;prealloc&quot;, &quot;yes&quot;,
 &quot;size&quot;, &quot;1048576&quot;,
 NULL)) {
 error_reportf_err(err, &quot;Cannot set properties: &quot;);
 }
</pre></div>
</div>
</div>
The returned object will have one stable reference maintained
for as long as it is present in the object hierarchy.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on error.
<dl class="function">
<dt id="c.object_set_propv">
bool <code class="descname">object_set_propv</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, Error&nbsp;**errp, va_list&nbsp;vargs)<a class="headerlink" href="#c.object_set_propv" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object instance to set properties on</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
<dt><code class="docutils literal notranslate">va_list vargs</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
See object_set_props() for documentation.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on error.
<dl class="function">
<dt id="c.object_initialize">
void <code class="descname">object_initialize</code>(void&nbsp;*obj, size_t&nbsp;size, const char&nbsp;*typename)<a class="headerlink" href="#c.object_initialize" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void *obj</code></dt>
<dd>A pointer to the memory to be used for the object.</dd>
<dt><code class="docutils literal notranslate">size_t size</code></dt>
<dd>The maximum size available at obj for the object.</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
</dl>
Description
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.
<dl class="function">
<dt id="c.object_initialize_child_with_props">
bool <code class="descname">object_initialize_child_with_props</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parentobj, const char&nbsp;*propname, void&nbsp;*childobj, size_t&nbsp;size, const char&nbsp;*type, Error&nbsp;**errp, ...)<a class="headerlink" href="#c.object_initialize_child_with_props" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *parentobj</code></dt>
<dd>The parent object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *propname</code></dt>
<dd>The name of the property</dd>
<dt><code class="docutils literal notranslate">void *childobj</code></dt>
<dd>A pointer to the memory to be used for the object.</dd>
<dt><code class="docutils literal notranslate">size_t size</code></dt>
<dd>The maximum size available at childobj for the object.</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>If an error occurs, a pointer to an area to store the error</dd>
<dt><code class="docutils literal notranslate">...</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
This function will initialize an object. The memory for the object should
have already been allocated. The object will then be added as child property
to a parent with object_property_add_child() function. The returned object
has a reference count of 1 (for the “child&lt;…&gt;” property from the parent),
so the object will be finalized automatically when the parent gets removed.
The variadic parameters are a list of pairs of (propname, propvalue)
strings. The propname of <code class="docutils literal notranslate">NULL</code> 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.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_initialize_child_with_propsv">
bool <code class="descname">object_initialize_child_with_propsv</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parentobj, const char&nbsp;*propname, void&nbsp;*childobj, size_t&nbsp;size, const char&nbsp;*type, Error&nbsp;**errp, va_list&nbsp;vargs)<a class="headerlink" href="#c.object_initialize_child_with_propsv" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *parentobj</code></dt>
<dd>The parent object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *propname</code></dt>
<dd>The name of the property</dd>
<dt><code class="docutils literal notranslate">void *childobj</code></dt>
<dd>A pointer to the memory to be used for the object.</dd>
<dt><code class="docutils literal notranslate">size_t size</code></dt>
<dd>The maximum size available at childobj for the object.</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>If an error occurs, a pointer to an area to store the error</dd>
<dt><code class="docutils literal notranslate">va_list vargs</code></dt>
<dd>list of property names and values</dd>
</dl>
Description
See object_initialize_child() for documentation.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_initialize_child">
<code class="descname">object_initialize_child</code>(parent, propname, child, type)<a class="headerlink" href="#c.object_initialize_child" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">parent</code></dt>
<dd>The parent object to add a property to</dd>
<dt><code class="docutils literal notranslate">propname</code></dt>
<dd>The name of the property</dd>
<dt><code class="docutils literal notranslate">child</code></dt>
<dd>A precisely typed pointer to the memory to be used for the
object.</dd>
<dt><code class="docutils literal notranslate">type</code></dt>
<dd>The name of the type of the object to instantiate.</dd>
</dl>
Description
This is like:
<div class="highlight-c notranslate"><div class="highlight"><pre>object_initialize_child_with_props(parent, propname,
 child, sizeof(*child), type,
 &amp;error_abort, NULL)
</pre></div>
</div>
<dl class="function">
<dt id="c.object_dynamic_cast">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_dynamic_cast</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*typename)<a class="headerlink" href="#c.object_dynamic_cast" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>The object to cast.</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The typename to cast to.</dd>
</dl>
Description
This function will determine if obj is-a typename. obj can refer to an
object or an interface associated with an object.
Return
This function returns obj on success or <code class="xref c c-type docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_dynamic_cast_assert">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_dynamic_cast_assert</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*typename, const char&nbsp;*file, int&nbsp;line, const char&nbsp;*func)<a class="headerlink" href="#c.object_dynamic_cast_assert" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>The object to cast.</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The typename to cast to.</dd>
<dt><code class="docutils literal notranslate">const char *file</code></dt>
<dd>Source code file where function was called</dd>
<dt><code class="docutils literal notranslate">int line</code></dt>
<dd>Source code line where function was called</dd>
<dt><code class="docutils literal notranslate">const char *func</code></dt>
<dd>Name of function where this function was called</dd>
</dl>
Description
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 <code class="xref c c-type docutils literal notranslate">NULL</code> 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.
<dl class="function">
<dt id="c.object_get_class">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">object_get_class</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj)<a class="headerlink" href="#c.object_get_class" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>A derivative of <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a></dd>
</dl>
Return
The <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a> of the type associated with obj.
<dl class="function">
<dt id="c.object_get_typename">
const char * <code class="descname">object_get_typename</code>(const <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj)<a class="headerlink" href="#c.object_get_typename" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const Object *obj</code></dt>
<dd>A derivative of <a class="reference internal" href="#c.Object" title="Object"><code class="xref c c-type docutils literal notranslate">Object</code></a>.</dd>
</dl>
Return
The QOM typename of obj.
<dl class="function">
<dt id="c.type_register_static">
Type <code class="descname">type_register_static</code>(const <a class="reference internal" href="#c.TypeInfo" title="TypeInfo">TypeInfo</a>&nbsp;*info)<a class="headerlink" href="#c.type_register_static" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const TypeInfo *info</code></dt>
<dd>The <a class="reference internal" href="#c.TypeInfo" title="TypeInfo"><code class="xref c c-type docutils literal notranslate">TypeInfo</code></a> of the new type.</dd>
</dl>
Description
info and all of the strings it points to should exist for the life time
that the type is registered.
Return
the new <code class="xref c c-type docutils literal notranslate">Type</code>.
<dl class="function">
<dt id="c.type_register">
Type <code class="descname">type_register</code>(const <a class="reference internal" href="#c.TypeInfo" title="TypeInfo">TypeInfo</a>&nbsp;*info)<a class="headerlink" href="#c.type_register" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const TypeInfo *info</code></dt>
<dd>The <a class="reference internal" href="#c.TypeInfo" title="TypeInfo"><code class="xref c c-type docutils literal notranslate">TypeInfo</code></a> of the new type</dd>
</dl>
Description
Unlike type_register_static(), this call does not require info or its
string members to continue to exist after the call returns.
Return
the new <code class="xref c c-type docutils literal notranslate">Type</code>.
<dl class="function">
<dt id="c.type_register_static_array">
void <code class="descname">type_register_static_array</code>(const <a class="reference internal" href="#c.TypeInfo" title="TypeInfo">TypeInfo</a>&nbsp;*infos, int&nbsp;nr_infos)<a class="headerlink" href="#c.type_register_static_array" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const TypeInfo *infos</code></dt>
<dd>The array of the new type <a class="reference internal" href="#c.TypeInfo" title="TypeInfo"><code class="xref c c-type docutils literal notranslate">TypeInfo</code></a> structures.</dd>
<dt><code class="docutils literal notranslate">int nr_infos</code></dt>
<dd>number of entries in infos</dd>
</dl>
Description
infos and all of the strings it points to should exist for the life time
that the type is registered.
<dl class="function">
<dt id="c.DEFINE_TYPES">
<code class="descname">DEFINE_TYPES</code>(type_array)<a class="headerlink" href="#c.DEFINE_TYPES" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">type_array</code></dt>
<dd>The array containing <a class="reference internal" href="#c.TypeInfo" title="TypeInfo"><code class="xref c c-type docutils literal notranslate">TypeInfo</code></a> structures to register</dd>
</dl>
Description
type_array should be static constant that exists for the life time
that the type is registered.
<dl class="function">
<dt id="c.type_print_class_properties">
bool <code class="descname">type_print_class_properties</code>(const char&nbsp;*type)<a class="headerlink" href="#c.type_print_class_properties" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>a QOM class name</dd>
</dl>
Description
Print the object’s class properties to stdout or the monitor.
Return whether an object was found.
<dl class="function">
<dt id="c.object_set_properties_from_keyval">
void <code class="descname">object_set_properties_from_keyval</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const QDict&nbsp;*qdict, bool&nbsp;from_json, Error&nbsp;**errp)<a class="headerlink" href="#c.object_set_properties_from_keyval" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>a QOM object</dd>
<dt><code class="docutils literal notranslate">const QDict *qdict</code></dt>
<dd>a dictionary with the properties to be set</dd>
<dt><code class="docutils literal notranslate">bool from_json</code></dt>
<dd>true if leaf values of qdict are typed, false if they
are strings</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
</dl>
Description
For each key in the dictionary, parse the value string if needed,
then set the corresponding property in obj.
<dl class="function">
<dt id="c.object_class_dynamic_cast_assert">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">object_class_dynamic_cast_assert</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass, const char&nbsp;*typename, const char&nbsp;*file, int&nbsp;line, const char&nbsp;*func)<a class="headerlink" href="#c.object_class_dynamic_cast_assert" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a> to attempt to cast.</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The QOM typename of the class to cast to.</dd>
<dt><code class="docutils literal notranslate">const char *file</code></dt>
<dd>Source code file where function was called</dd>
<dt><code class="docutils literal notranslate">int line</code></dt>
<dd>Source code line where function was called</dd>
<dt><code class="docutils literal notranslate">const char *func</code></dt>
<dd>Name of function where this function was called</dd>
</dl>
Description
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 <code class="xref c c-type docutils literal notranslate">NULL</code> on failure if QOM cast debugging is
enabled. This function is not meant to be called directly, but only through
the wrapper macro OBJECT_CLASS_CHECK.
<dl class="function">
<dt id="c.object_class_dynamic_cast">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">object_class_dynamic_cast</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass, const char&nbsp;*typename)<a class="headerlink" href="#c.object_class_dynamic_cast" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The <a class="reference internal" href="#c.ObjectClass" title="ObjectClass"><code class="xref c c-type docutils literal notranslate">ObjectClass</code></a> to attempt to cast.</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The QOM typename of the class to cast to.</dd>
</dl>
Return
If typename is a class, this function returns klass if
typename is a subtype of klass, else returns <code class="xref c c-type docutils literal notranslate">NULL</code>.
Description
If typename is an interface, this function returns the interface
definition for klass if klass implements it unambiguously; <code class="xref c c-type docutils literal notranslate">NULL</code>
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?)
<dl class="function">
<dt id="c.object_class_get_parent">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">object_class_get_parent</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass)<a class="headerlink" href="#c.object_class_get_parent" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The class to obtain the parent for.</dd>
</dl>
Return
The parent for klass or <code class="docutils literal notranslate">NULL</code> if none.
<dl class="function">
<dt id="c.object_class_get_name">
const char * <code class="descname">object_class_get_name</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass)<a class="headerlink" href="#c.object_class_get_name" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The class to obtain the QOM typename for.</dd>
</dl>
Return
The QOM typename for klass.
<dl class="function">
<dt id="c.object_class_is_abstract">
bool <code class="descname">object_class_is_abstract</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass)<a class="headerlink" href="#c.object_class_is_abstract" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>The class to obtain the abstractness for.</dd>
</dl>
Return
<code class="docutils literal notranslate">true</code> if klass is abstract, <code class="docutils literal notranslate">false</code> otherwise.
<dl class="function">
<dt id="c.object_class_by_name">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">object_class_by_name</code>(const char&nbsp;*typename)<a class="headerlink" href="#c.object_class_by_name" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The QOM typename to obtain the class for.</dd>
</dl>
Return
The class for typename or <code class="docutils literal notranslate">NULL</code> if not found.
<dl class="function">
<dt id="c.module_object_class_by_name">
<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a> * <code class="descname">module_object_class_by_name</code>(const char&nbsp;*typename)<a class="headerlink" href="#c.module_object_class_by_name" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>The QOM typename to obtain the class for.</dd>
</dl>
Description
For objects which might be provided by a module. Behaves like
object_class_by_name, but additionally tries to load the module
needed in case the class is not available.
Return
The class for typename or <code class="docutils literal notranslate">NULL</code> if not found.
<dl class="function">
<dt id="c.object_class_get_list">
GSList * <code class="descname">object_class_get_list</code>(const char&nbsp;*implements_type, bool&nbsp;include_abstract)<a class="headerlink" href="#c.object_class_get_list" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *implements_type</code></dt>
<dd>The type to filter for, including its derivatives.</dd>
<dt><code class="docutils literal notranslate">bool include_abstract</code></dt>
<dd>Whether to include abstract classes.</dd>
</dl>
Return
A singly-linked list of the classes in reverse hashtable order.
<dl class="function">
<dt id="c.object_class_get_list_sorted">
GSList * <code class="descname">object_class_get_list_sorted</code>(const char&nbsp;*implements_type, bool&nbsp;include_abstract)<a class="headerlink" href="#c.object_class_get_list_sorted" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *implements_type</code></dt>
<dd>The type to filter for, including its derivatives.</dd>
<dt><code class="docutils literal notranslate">bool include_abstract</code></dt>
<dd>Whether to include abstract classes.</dd>
</dl>
Return
A singly-linked list of the classes in alphabetical
case-insensitive order.
<dl class="function">
<dt id="c.object_ref">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_ref</code>(void&nbsp;*obj)<a class="headerlink" href="#c.object_ref" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void *obj</code></dt>
<dd>the object</dd>
</dl>
Description
Increase the reference count of a object. A object cannot be freed as long
as its reference count is greater than zero.
Return
obj
<dl class="function">
<dt id="c.object_unref">
void <code class="descname">object_unref</code>(void&nbsp;*obj)<a class="headerlink" href="#c.object_unref" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void *obj</code></dt>
<dd>the object</dd>
</dl>
Description
Decrease the reference count of a object. A object cannot be freed as long
as its reference count is greater than zero.
<dl class="function">
<dt id="c.object_property_try_add">
ObjectProperty * <code class="descname">object_property_try_add</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*type, <a class="reference internal" href="#c.ObjectPropertyAccessor" title="ObjectPropertyAccessor">ObjectPropertyAccessor</a>&nbsp;*get, <a class="reference internal" href="#c.ObjectPropertyAccessor" title="ObjectPropertyAccessor">ObjectPropertyAccessor</a>&nbsp;*set, <a class="reference internal" href="#c.ObjectPropertyRelease" title="ObjectPropertyRelease">ObjectPropertyRelease</a>&nbsp;*release, void&nbsp;*opaque, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_try_add" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>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&lt;virtio-net-pci&gt;’.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyAccessor *get</code></dt>
<dd>The getter to be called to read a property. If this is NULL, then
the property cannot be read.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyAccessor *set</code></dt>
<dd>the setter to be called to write a property. If this is NULL,
then the property cannot be written.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyRelease *release</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>an opaque pointer to pass to the callbacks for the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
</dl>
Return
The <code class="xref c c-type docutils literal notranslate">ObjectProperty</code>; this can be used to set the resolve
callback for child and link properties.
<dl class="function">
<dt id="c.object_property_add">
ObjectProperty * <code class="descname">object_property_add</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*type, <a class="reference internal" href="#c.ObjectPropertyAccessor" title="ObjectPropertyAccessor">ObjectPropertyAccessor</a>&nbsp;*get, <a class="reference internal" href="#c.ObjectPropertyAccessor" title="ObjectPropertyAccessor">ObjectPropertyAccessor</a>&nbsp;*set, <a class="reference internal" href="#c.ObjectPropertyRelease" title="ObjectPropertyRelease">ObjectPropertyRelease</a>&nbsp;*release, void&nbsp;*opaque)<a class="headerlink" href="#c.object_property_add" title="Permalink to this definition">¶</a></dt>
<dd>Same as object_property_try_add() with errp hardcoded to &amp;error_abort.
</dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>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&lt;virtio-net-pci&gt;’.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyAccessor *get</code></dt>
<dd>The getter to be called to read a property. If this is NULL, then
the property cannot be read.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyAccessor *set</code></dt>
<dd>the setter to be called to write a property. If this is NULL,
then the property cannot be written.</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyRelease *release</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>an opaque pointer to pass to the callbacks for the property</dd>
</dl>
<dl class="function">
<dt id="c.object_property_set_default_bool">
void <code class="descname">object_property_set_default_bool</code>(ObjectProperty&nbsp;*prop, bool&nbsp;value)<a class="headerlink" href="#c.object_property_set_default_bool" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectProperty *prop</code></dt>
<dd>the property to set</dd>
<dt><code class="docutils literal notranslate">bool value</code></dt>
<dd>the value to be written to the property</dd>
</dl>
Description
Set the property default value.
<dl class="function">
<dt id="c.object_property_set_default_str">
void <code class="descname">object_property_set_default_str</code>(ObjectProperty&nbsp;*prop, const char&nbsp;*value)<a class="headerlink" href="#c.object_property_set_default_str" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectProperty *prop</code></dt>
<dd>the property to set</dd>
<dt><code class="docutils literal notranslate">const char *value</code></dt>
<dd>the value to be written to the property</dd>
</dl>
Description
Set the property default value.
<dl class="function">
<dt id="c.object_property_set_default_int">
void <code class="descname">object_property_set_default_int</code>(ObjectProperty&nbsp;*prop, int64_t&nbsp;value)<a class="headerlink" href="#c.object_property_set_default_int" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectProperty *prop</code></dt>
<dd>the property to set</dd>
<dt><code class="docutils literal notranslate">int64_t value</code></dt>
<dd>the value to be written to the property</dd>
</dl>
Description
Set the property default value.
<dl class="function">
<dt id="c.object_property_set_default_uint">
void <code class="descname">object_property_set_default_uint</code>(ObjectProperty&nbsp;*prop, uint64_t&nbsp;value)<a class="headerlink" href="#c.object_property_set_default_uint" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectProperty *prop</code></dt>
<dd>the property to set</dd>
<dt><code class="docutils literal notranslate">uint64_t value</code></dt>
<dd>the value to be written to the property</dd>
</dl>
Description
Set the property default value.
<dl class="function">
<dt id="c.object_property_find">
ObjectProperty * <code class="descname">object_property_find</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name)<a class="headerlink" href="#c.object_property_find" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
</dl>
Description
Look up a property for an object.
Return its <code class="xref c c-type docutils literal notranslate">ObjectProperty</code> if found, or NULL.
<dl class="function">
<dt id="c.object_property_find_err">
ObjectProperty * <code class="descname">object_property_find_err</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_find_err" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Look up a property for an object.
Return its <code class="xref c c-type docutils literal notranslate">ObjectProperty</code> if found, or NULL.
<dl class="function">
<dt id="c.object_class_property_find">
ObjectProperty * <code class="descname">object_class_property_find</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass, const char&nbsp;*name)<a class="headerlink" href="#c.object_class_property_find" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>the object class</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
</dl>
Description
Look up a property for an object class.
Return its <code class="xref c c-type docutils literal notranslate">ObjectProperty</code> if found, or NULL.
<dl class="function">
<dt id="c.object_class_property_find_err">
ObjectProperty * <code class="descname">object_class_property_find_err</code>(<a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_class_property_find_err" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>the object class</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Look up a property for an object class.
Return its <code class="xref c c-type docutils literal notranslate">ObjectProperty</code> if found, or NULL.
<dl class="function">
<dt id="c.object_property_iter_init">
void <code class="descname">object_property_iter_init</code>(ObjectPropertyIterator&nbsp;*iter, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj)<a class="headerlink" href="#c.object_property_iter_init" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectPropertyIterator *iter</code></dt>
<dd>the iterator instance</dd>
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
</dl>
Description
Initializes an iterator for traversing all properties
registered against an object instance, its class and all parent classes.
It is forbidden to modify the property list while iterating,
whether removing or adding properties.
Typical usage pattern would be
<div class="literal-block-wrapper docutils container" id="id14">
<div class="code-block-caption">Using object property iterators<a class="headerlink" href="#id14" title="Permalink to this code">¶</a></div>
<div class="highlight-c notranslate"><div class="highlight"><pre> ObjectProperty *prop;
 ObjectPropertyIterator iter;

object_property_iter_init(&amp;iter, obj);
 while ((prop = object_property_iter_next(&amp;iter))) {
 ... do something with prop ...
 }
</pre></div>
</div>
</div>
<dl class="function">
<dt id="c.object_class_property_iter_init">
void <code class="descname">object_class_property_iter_init</code>(ObjectPropertyIterator&nbsp;*iter, <a class="reference internal" href="#c.ObjectClass" title="ObjectClass">ObjectClass</a>&nbsp;*klass)<a class="headerlink" href="#c.object_class_property_iter_init" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectPropertyIterator *iter</code></dt>
<dd>the iterator instance</dd>
<dt><code class="docutils literal notranslate">ObjectClass *klass</code></dt>
<dd>the class</dd>
</dl>
Description
Initializes an iterator for traversing all properties
registered against an object class and all parent classes.
It is forbidden to modify the property list while iterating,
whether removing or adding properties.
This can be used on abstract classes as it does not create a temporary
instance.
<dl class="function">
<dt id="c.object_property_iter_next">
ObjectProperty * <code class="descname">object_property_iter_next</code>(ObjectPropertyIterator&nbsp;*iter)<a class="headerlink" href="#c.object_property_iter_next" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">ObjectPropertyIterator *iter</code></dt>
<dd>the iterator instance</dd>
</dl>
Description
Return the next available property. If no further properties
are available, a <code class="docutils literal notranslate">NULL</code> value will be returned and the iter
pointer should not be used again after this point without
re-initializing it.
Return
the next property, or <code class="docutils literal notranslate">NULL</code> when all properties
have been traversed.
<dl class="function">
<dt id="c.object_property_get">
bool <code class="descname">object_property_get</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Visitor&nbsp;*v, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Visitor *v</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Reads a property from a object.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_set_str">
bool <code class="descname">object_property_set_str</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*value, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set_str" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *value</code></dt>
<dd>the value to be written to the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes a string value to a property.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_get_str">
char * <code class="descname">object_property_get_str</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_str" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
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.
<dl class="function">
<dt id="c.object_property_set_link">
bool <code class="descname">object_property_set_link</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*value, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set_link" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *value</code></dt>
<dd>the value to be written to the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes an object’s canonical path to a property.
If the link property was created with
<code class="docutils literal notranslate">OBJ_PROP_LINK_STRONG</code> bit, the old target object is
unreferenced, and a reference is added to the new target object.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_get_link">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_property_get_link</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_link" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
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).
<dl class="function">
<dt id="c.object_property_set_bool">
bool <code class="descname">object_property_set_bool</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, bool&nbsp;value, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set_bool" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">bool value</code></dt>
<dd>the value to be written to the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes a bool value to a property.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_get_bool">
bool <code class="descname">object_property_get_bool</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_bool" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
the value of the property, converted to a boolean, or false if
an error occurs (including when the property value is not a bool).
<dl class="function">
<dt id="c.object_property_set_int">
bool <code class="descname">object_property_set_int</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, int64_t&nbsp;value, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set_int" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">int64_t value</code></dt>
<dd>the value to be written to the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes an integer value to a property.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_get_int">
int64_t <code class="descname">object_property_get_int</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_int" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
the value of the property, converted to an integer, or -1 if
an error occurs (including when the property value is not an integer).
<dl class="function">
<dt id="c.object_property_set_uint">
bool <code class="descname">object_property_set_uint</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, uint64_t&nbsp;value, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set_uint" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">uint64_t value</code></dt>
<dd>the value to be written to the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes an unsigned integer value to a property.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_get_uint">
uint64_t <code class="descname">object_property_get_uint</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_uint" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
the value of the property, converted to an unsigned integer, or 0
an error occurs (including when the property value is not an integer).
<dl class="function">
<dt id="c.object_property_get_enum">
int <code class="descname">object_property_get_enum</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*typename, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_enum" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>the name of the enum data type</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
the value of the property, converted to an integer (which
can’t be negative), or -1 on error (including when the property
value is not an enum).
<dl class="function">
<dt id="c.object_property_set">
bool <code class="descname">object_property_set</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Visitor&nbsp;*v, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_set" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Visitor *v</code></dt>
<dd>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.</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Writes a property to a object.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_parse">
bool <code class="descname">object_property_parse</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*string, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_parse" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *string</code></dt>
<dd>the string that will be used to parse the property value.</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Parses a string and writes the result into a property of an object.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_property_print">
char * <code class="descname">object_property_print</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, bool&nbsp;human, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_print" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">bool human</code></dt>
<dd>if true, print for human consumption</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Description
Returns a string representation of the value of the property. The
caller shall free the string.
<dl class="function">
<dt id="c.object_property_get_type">
const char * <code class="descname">object_property_get_type</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_get_type" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>returns an error if this function fails</dd>
</dl>
Return
The type name of the property.
<dl class="function">
<dt id="c.object_get_root">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_get_root</code>(void)<a class="headerlink" href="#c.object_get_root" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void</code></dt>
<dd>no arguments</dd>
</dl>
Return
the root object of the composition tree
<dl class="function">
<dt id="c.object_get_objects_root">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_get_objects_root</code>(void)<a class="headerlink" href="#c.object_get_objects_root" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void</code></dt>
<dd>no arguments</dd>
</dl>
Description
Get the container object that holds user created
object instances. This is the object at path
“/objects”
Return
the user object container
<dl class="function">
<dt id="c.object_get_internal_root">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_get_internal_root</code>(void)<a class="headerlink" href="#c.object_get_internal_root" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">void</code></dt>
<dd>no arguments</dd>
</dl>
Description
Get the container object that holds internally used object
instances. Any object which is put into this container must not be
user visible, and it will not be exposed in the QOM tree.
Return
the internal object container
<dl class="function">
<dt id="c.object_get_canonical_path_component">
const char * <code class="descname">object_get_canonical_path_component</code>(const <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj)<a class="headerlink" href="#c.object_get_canonical_path_component" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const Object *obj</code></dt>
<dd>the object</dd>
</dl>
Return
The final component in the object’s canonical path. The canonical
path is the path within the composition tree starting from the root.
<code class="docutils literal notranslate">NULL</code> if the object doesn’t have a parent (and thus a canonical path).
<dl class="function">
<dt id="c.object_get_canonical_path">
char * <code class="descname">object_get_canonical_path</code>(const <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj)<a class="headerlink" href="#c.object_get_canonical_path" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const Object *obj</code></dt>
<dd>the object</dd>
</dl>
Return
The canonical path for a object, newly allocated. This is
the path within the composition tree starting from the root. Use
g_free() to free it.
<dl class="function">
<dt id="c.object_resolve_path">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_resolve_path</code>(const char&nbsp;*path, bool&nbsp;*ambiguous)<a class="headerlink" href="#c.object_resolve_path" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *path</code></dt>
<dd>the path to resolve</dd>
<dt><code class="docutils literal notranslate">bool *ambiguous</code></dt>
<dd>returns true if the path resolution failed because of an
ambiguous match</dd>
</dl>
Description
There are two types of supported paths–absolute paths and partial paths.
Absolute paths are derived from the root object and can follow child&lt;&gt; or
link&lt;&gt; properties. Since they can follow link&lt;&gt; 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.
Return
The matched object or NULL on path lookup failure.
<dl class="function">
<dt id="c.object_resolve_path_type">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_resolve_path_type</code>(const char&nbsp;*path, const char&nbsp;*typename, bool&nbsp;*ambiguous)<a class="headerlink" href="#c.object_resolve_path_type" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *path</code></dt>
<dd>the path to resolve</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>the type to look for.</dd>
<dt><code class="docutils literal notranslate">bool *ambiguous</code></dt>
<dd>returns true if the path resolution failed because of an
ambiguous match</dd>
</dl>
Description
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.
Return
The matched object or NULL on path lookup failure.
<dl class="function">
<dt id="c.object_resolve_path_at">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_resolve_path_at</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parent, const char&nbsp;*path)<a class="headerlink" href="#c.object_resolve_path_at" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *parent</code></dt>
<dd>the object in which to resolve the path</dd>
<dt><code class="docutils literal notranslate">const char *path</code></dt>
<dd>the path to resolve</dd>
</dl>
Description
This is like object_resolve_path(), except paths not starting with
a slash are relative to parent.
Return
The resolved object or NULL on path lookup failure.
<dl class="function">
<dt id="c.object_resolve_path_component">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">object_resolve_path_component</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*parent, const char&nbsp;*part)<a class="headerlink" href="#c.object_resolve_path_component" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *parent</code></dt>
<dd>the object in which to resolve the path</dd>
<dt><code class="docutils literal notranslate">const char *part</code></dt>
<dd>the component to resolve.</dd>
</dl>
Description
This is similar to object_resolve_path with an absolute path, but it
only resolves one element (part) and takes the others from parent.
Return
The resolved object or NULL on path lookup failure.
<dl class="function">
<dt id="c.object_property_try_add_child">
ObjectProperty * <code class="descname">object_property_try_add_child</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*child, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_try_add_child" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *child</code></dt>
<dd>the child object</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
</dl>
Description
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().
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_child">
ObjectProperty * <code class="descname">object_property_add_child</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*child)<a class="headerlink" href="#c.object_property_add_child" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *child</code></dt>
<dd>the child object</dd>
</dl>
Description
Same as object_property_try_add_child() with errp hardcoded to
&amp;error_abort
<dl class="function">
<dt id="c.object_property_allow_set_link">
void <code class="descname">object_property_allow_set_link</code>(const <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*child, Error&nbsp;**errp)<a class="headerlink" href="#c.object_property_allow_set_link" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *child</code></dt>
<dd>the child object</dd>
<dt><code class="docutils literal notranslate">Error **errp</code></dt>
<dd>pointer to error object</dd>
</dl>
Description
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.
<dl class="function">
<dt id="c.object_property_add_link">
ObjectProperty * <code class="descname">object_property_add_link</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*type, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;**targetp, void (*check)(const <a class="reference internal" href="#c.Object" title="Object">Object</a> *obj, const char *name, <a class="reference internal" href="#c.Object" title="Object">Object</a> *val, Error **errp), ObjectPropertyLinkFlags&nbsp;flags)<a class="headerlink" href="#c.object_property_add_link" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>the qobj type of the link</dd>
<dt><code class="docutils literal notranslate">Object **targetp</code></dt>
<dd>a pointer to where the link object reference is stored</dd>
<dt><code class="docutils literal notranslate">void (*check)(const Object *obj, const char *name, Object *val, Error **errp)</code></dt>
<dd>callback to veto setting or NULL if the property is read-only</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyLinkFlags flags</code></dt>
<dd>additional options for the link</dd>
</dl>
Description
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 check() callback is invoked when
object_property_set_link() is called and can raise an error to prevent the
link being set. If check 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 *child is
managed by the property from after the function returns till the
property is deleted with object_property_del(). If the
flags <code class="docutils literal notranslate">OBJ_PROP_LINK_STRONG</code> bit is set,
the reference count is decremented when the property is deleted or
modified.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_str">
ObjectProperty * <code class="descname">object_property_add_str</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, char *(*get)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, Error **), void (*set)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, const char *, Error **))<a class="headerlink" href="#c.object_property_add_str" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">char *(*get)(Object *, Error **)</code></dt>
<dd>the getter or NULL if the property is write-only. This function must
return a string to be freed by g_free().</dd>
<dt><code class="docutils literal notranslate">void (*set)(Object *, const char *, Error **)</code></dt>
<dd>the setter or NULL if the property is read-only</dd>
</dl>
Description
Add a string property using getters/setters. This function will add a
property of type ‘string’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_bool">
ObjectProperty * <code class="descname">object_property_add_bool</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, bool (*get)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, Error **), void (*set)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, bool, Error **))<a class="headerlink" href="#c.object_property_add_bool" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">bool (*get)(Object *, Error **)</code></dt>
<dd>the getter or NULL if the property is write-only.</dd>
<dt><code class="docutils literal notranslate">void (*set)(Object *, bool, Error **)</code></dt>
<dd>the setter or NULL if the property is read-only</dd>
</dl>
Description
Add a bool property using getters/setters. This function will add a
property of type ‘bool’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_enum">
ObjectProperty * <code class="descname">object_property_add_enum</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*typename, const QEnumLookup&nbsp;*lookup, int (*get)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, Error **), void (*set)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, int, Error **))<a class="headerlink" href="#c.object_property_add_enum" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>the name of the enum data type</dd>
<dt><code class="docutils literal notranslate">const QEnumLookup *lookup</code></dt>
<dd>enum value namelookup table</dd>
<dt><code class="docutils literal notranslate">int (*get)(Object *, Error **)</code></dt>
<dd>the getter or <code class="docutils literal notranslate">NULL</code> if the property is write-only.</dd>
<dt><code class="docutils literal notranslate">void (*set)(Object *, int, Error **)</code></dt>
<dd>the setter or <code class="docutils literal notranslate">NULL</code> if the property is read-only</dd>
</dl>
Description
Add an enum property using getters/setters. This function will add a
property of type ‘typename’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_tm">
ObjectProperty * <code class="descname">object_property_add_tm</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, void (*get)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *, struct tm *, Error **))<a class="headerlink" href="#c.object_property_add_tm" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">void (*get)(Object *, struct tm *, Error **)</code></dt>
<dd>the getter or NULL if the property is write-only.</dd>
</dl>
Description
Add a read-only struct tm valued property using a getter function.
This function will add a property of type ‘struct tm’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_uint8_ptr">
ObjectProperty * <code class="descname">object_property_add_uint8_ptr</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const uint8_t&nbsp;*v, ObjectPropertyFlags&nbsp;flags)<a class="headerlink" href="#c.object_property_add_uint8_ptr" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const uint8_t *v</code></dt>
<dd>pointer to value</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyFlags flags</code></dt>
<dd>bitwise-or’d ObjectPropertyFlags</dd>
</dl>
Description
Add an integer property in memory. This function will add a
property of type ‘uint8’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_uint16_ptr">
ObjectProperty * <code class="descname">object_property_add_uint16_ptr</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const uint16_t&nbsp;*v, ObjectPropertyFlags&nbsp;flags)<a class="headerlink" href="#c.object_property_add_uint16_ptr" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const uint16_t *v</code></dt>
<dd>pointer to value</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyFlags flags</code></dt>
<dd>bitwise-or’d ObjectPropertyFlags</dd>
</dl>
Description
Add an integer property in memory. This function will add a
property of type ‘uint16’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_uint32_ptr">
ObjectProperty * <code class="descname">object_property_add_uint32_ptr</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const uint32_t&nbsp;*v, ObjectPropertyFlags&nbsp;flags)<a class="headerlink" href="#c.object_property_add_uint32_ptr" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const uint32_t *v</code></dt>
<dd>pointer to value</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyFlags flags</code></dt>
<dd>bitwise-or’d ObjectPropertyFlags</dd>
</dl>
Description
Add an integer property in memory. This function will add a
property of type ‘uint32’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_uint64_ptr">
ObjectProperty * <code class="descname">object_property_add_uint64_ptr</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const uint64_t&nbsp;*v, ObjectPropertyFlags&nbsp;flags)<a class="headerlink" href="#c.object_property_add_uint64_ptr" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const uint64_t *v</code></dt>
<dd>pointer to value</dd>
<dt><code class="docutils literal notranslate">ObjectPropertyFlags flags</code></dt>
<dd>bitwise-or’d ObjectPropertyFlags</dd>
</dl>
Description
Add an integer property in memory. This function will add a
property of type ‘uint64’.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_alias">
ObjectProperty * <code class="descname">object_property_add_alias</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*target_obj, const char&nbsp;*target_name)<a class="headerlink" href="#c.object_property_add_alias" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *target_obj</code></dt>
<dd>the object to forward property access to</dd>
<dt><code class="docutils literal notranslate">const char *target_name</code></dt>
<dd>the name of the property on the forwarded object</dd>
</dl>
Description
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 target_obj 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.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_add_const_link">
ObjectProperty * <code class="descname">object_property_add_const_link</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, <a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*target)<a class="headerlink" href="#c.object_property_add_const_link" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object to add a property to</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">Object *target</code></dt>
<dd>the object to be referred by the link</dd>
</dl>
Description
Add an unmodifiable link for a property on an object. This function will
add a property of type link&lt;TYPE&gt; 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.
Return
The newly added property on success, or <code class="docutils literal notranslate">NULL</code> on failure.
<dl class="function">
<dt id="c.object_property_set_description">
void <code class="descname">object_property_set_description</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, const char&nbsp;*name, const char&nbsp;*description)<a class="headerlink" href="#c.object_property_set_description" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object owning the property</dd>
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *description</code></dt>
<dd>the description of the property on the object</dd>
</dl>
Description
Set an object property’s description.
Return
<code class="docutils literal notranslate">true</code> on success, <code class="docutils literal notranslate">false</code> on failure.
<dl class="function">
<dt id="c.object_child_foreach">
int <code class="descname">object_child_foreach</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, int (*fn)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *child, void *opaque), void&nbsp;*opaque)<a class="headerlink" href="#c.object_child_foreach" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object whose children will be navigated</dd>
<dt><code class="docutils literal notranslate">int (*fn)(Object *child, void *opaque)</code></dt>
<dd>the iterator function to be called</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>an opaque value that will be passed to the iterator</dd>
</dl>
Description
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.
Return
The last value returned by fn, or 0 if there is no child.
<dl class="function">
<dt id="c.object_child_foreach_recursive">
int <code class="descname">object_child_foreach_recursive</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*obj, int (*fn)(<a class="reference internal" href="#c.Object" title="Object">Object</a> *child, void *opaque), void&nbsp;*opaque)<a class="headerlink" href="#c.object_child_foreach_recursive" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *obj</code></dt>
<dd>the object whose children will be navigated</dd>
<dt><code class="docutils literal notranslate">int (*fn)(Object *child, void *opaque)</code></dt>
<dd>the iterator function to be called</dd>
<dt><code class="docutils literal notranslate">void *opaque</code></dt>
<dd>an opaque value that will be passed to the iterator</dd>
</dl>
Description
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.
Return
The last value returned by fn, or 0 if there is no child.
<dl class="function">
<dt id="c.container_get">
<a class="reference internal" href="#c.Object" title="Object">Object</a> * <code class="descname">container_get</code>(<a class="reference internal" href="#c.Object" title="Object">Object</a>&nbsp;*root, const char&nbsp;*path)<a class="headerlink" href="#c.container_get" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">Object *root</code></dt>
<dd>root of the #path, e.g., object_get_root()</dd>
<dt><code class="docutils literal notranslate">const char *path</code></dt>
<dd>path to the container</dd>
</dl>
Description
Return a container object whose path is path. Create more containers
along the path if necessary.
Return
the container object.
<dl class="function">
<dt id="c.object_type_get_instance_size">
size_t <code class="descname">object_type_get_instance_size</code>(const char&nbsp;*typename)<a class="headerlink" href="#c.object_type_get_instance_size" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *typename</code></dt>
<dd>Name of the Type whose instance_size is required</dd>
</dl>
Description
Returns the instance_size of the given typename.
<dl class="function">
<dt id="c.object_property_help">
char * <code class="descname">object_property_help</code>(const char&nbsp;*name, const char&nbsp;*type, QObject&nbsp;*defval, const char&nbsp;*description)<a class="headerlink" href="#c.object_property_help" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

Parameters
<dl class="docutils">
<dt><code class="docutils literal notranslate">const char *name</code></dt>
<dd>the name of the property</dd>
<dt><code class="docutils literal notranslate">const char *type</code></dt>
<dd>the type of the property</dd>
<dt><code class="docutils literal notranslate">QObject *defval</code></dt>
<dd>the default value</dd>
<dt><code class="docutils literal notranslate">const char *description</code></dt>
<dd>description of the property</dd>
</dl>
Return
a user-friendly formatted string describing the property
for help purposes.
</div>
</div>
</div>

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