qemu/include/qom/object.h
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   1/*
   2 * QEMU Object Model
   3 *
   4 * Copyright IBM, Corp. 2011
   5 *
   6 * Authors:
   7 *  Anthony Liguori   <aliguori@us.ibm.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10 * See the COPYING file in the top-level directory.
  11 *
  12 */
  13
  14#ifndef QEMU_OBJECT_H
  15#define QEMU_OBJECT_H
  16
  17#include "qapi/qapi-builtin-types.h"
  18#include "qemu/module.h"
  19
  20struct TypeImpl;
  21typedef struct TypeImpl *Type;
  22
  23typedef struct TypeInfo TypeInfo;
  24
  25typedef struct InterfaceClass InterfaceClass;
  26typedef struct InterfaceInfo InterfaceInfo;
  27
  28#define TYPE_OBJECT "object"
  29#define TYPE_CONTAINER "container"
  30
  31typedef struct ObjectProperty ObjectProperty;
  32
  33/**
  34 * typedef ObjectPropertyAccessor:
  35 * @obj: the object that owns the property
  36 * @v: the visitor that contains the property data
  37 * @name: the name of the property
  38 * @opaque: the object property opaque
  39 * @errp: a pointer to an Error that is filled if getting/setting fails.
  40 *
  41 * Called when trying to get/set a property.
  42 */
  43typedef void (ObjectPropertyAccessor)(Object *obj,
  44                                      Visitor *v,
  45                                      const char *name,
  46                                      void *opaque,
  47                                      Error **errp);
  48
  49/**
  50 * typedef ObjectPropertyResolve:
  51 * @obj: the object that owns the property
  52 * @opaque: the opaque registered with the property
  53 * @part: the name of the property
  54 *
  55 * Resolves the #Object corresponding to property @part.
  56 *
  57 * The returned object can also be used as a starting point
  58 * to resolve a relative path starting with "@part".
  59 *
  60 * Returns: If @path is the path that led to @obj, the function
  61 * returns the #Object corresponding to "@path/@part".
  62 * If "@path/@part" is not a valid object path, it returns #NULL.
  63 */
  64typedef Object *(ObjectPropertyResolve)(Object *obj,
  65                                        void *opaque,
  66                                        const char *part);
  67
  68/**
  69 * typedef ObjectPropertyRelease:
  70 * @obj: the object that owns the property
  71 * @name: the name of the property
  72 * @opaque: the opaque registered with the property
  73 *
  74 * Called when a property is removed from a object.
  75 */
  76typedef void (ObjectPropertyRelease)(Object *obj,
  77                                     const char *name,
  78                                     void *opaque);
  79
  80/**
  81 * typedef ObjectPropertyInit:
  82 * @obj: the object that owns the property
  83 * @prop: the property to set
  84 *
  85 * Called when a property is initialized.
  86 */
  87typedef void (ObjectPropertyInit)(Object *obj, ObjectProperty *prop);
  88
  89struct ObjectProperty
  90{
  91    char *name;
  92    char *type;
  93    char *description;
  94    ObjectPropertyAccessor *get;
  95    ObjectPropertyAccessor *set;
  96    ObjectPropertyResolve *resolve;
  97    ObjectPropertyRelease *release;
  98    ObjectPropertyInit *init;
  99    void *opaque;
 100    QObject *defval;
 101};
 102
 103/**
 104 * typedef ObjectUnparent:
 105 * @obj: the object that is being removed from the composition tree
 106 *
 107 * Called when an object is being removed from the QOM composition tree.
 108 * The function should remove any backlinks from children objects to @obj.
 109 */
 110typedef void (ObjectUnparent)(Object *obj);
 111
 112/**
 113 * typedef ObjectFree:
 114 * @obj: the object being freed
 115 *
 116 * Called when an object's last reference is removed.
 117 */
 118typedef void (ObjectFree)(void *obj);
 119
 120#define OBJECT_CLASS_CAST_CACHE 4
 121
 122/**
 123 * struct ObjectClass:
 124 *
 125 * The base for all classes.  The only thing that #ObjectClass contains is an
 126 * integer type handle.
 127 */
 128struct ObjectClass
 129{
 130    /* private: */
 131    Type type;
 132    GSList *interfaces;
 133
 134    const char *object_cast_cache[OBJECT_CLASS_CAST_CACHE];
 135    const char *class_cast_cache[OBJECT_CLASS_CAST_CACHE];
 136
 137    ObjectUnparent *unparent;
 138
 139    GHashTable *properties;
 140};
 141
 142/**
 143 * struct Object:
 144 *
 145 * The base for all objects.  The first member of this object is a pointer to
 146 * a #ObjectClass.  Since C guarantees that the first member of a structure
 147 * always begins at byte 0 of that structure, as long as any sub-object places
 148 * its parent as the first member, we can cast directly to a #Object.
 149 *
 150 * As a result, #Object contains a reference to the objects type as its
 151 * first member.  This allows identification of the real type of the object at
 152 * run time.
 153 */
 154struct Object
 155{
 156    /* private: */
 157    ObjectClass *class;
 158    ObjectFree *free;
 159    GHashTable *properties;
 160    uint32_t ref;
 161    Object *parent;
 162};
 163
 164/**
 165 * DECLARE_INSTANCE_CHECKER:
 166 * @InstanceType: instance struct name
 167 * @OBJ_NAME: the object name in uppercase with underscore separators
 168 * @TYPENAME: type name
 169 *
 170 * Direct usage of this macro should be avoided, and the complete
 171 * OBJECT_DECLARE_TYPE macro is recommended instead.
 172 *
 173 * This macro will provide the instance type cast functions for a
 174 * QOM type.
 175 */
 176#define DECLARE_INSTANCE_CHECKER(InstanceType, OBJ_NAME, TYPENAME) \
 177    static inline G_GNUC_UNUSED InstanceType * \
 178    OBJ_NAME(const void *obj) \
 179    { return OBJECT_CHECK(InstanceType, obj, TYPENAME); }
 180
 181/**
 182 * DECLARE_CLASS_CHECKERS:
 183 * @ClassType: class struct name
 184 * @OBJ_NAME: the object name in uppercase with underscore separators
 185 * @TYPENAME: type name
 186 *
 187 * Direct usage of this macro should be avoided, and the complete
 188 * OBJECT_DECLARE_TYPE macro is recommended instead.
 189 *
 190 * This macro will provide the class type cast functions for a
 191 * QOM type.
 192 */
 193#define DECLARE_CLASS_CHECKERS(ClassType, OBJ_NAME, TYPENAME) \
 194    static inline G_GNUC_UNUSED ClassType * \
 195    OBJ_NAME##_GET_CLASS(const void *obj) \
 196    { return OBJECT_GET_CLASS(ClassType, obj, TYPENAME); } \
 197    \
 198    static inline G_GNUC_UNUSED ClassType * \
 199    OBJ_NAME##_CLASS(const void *klass) \
 200    { return OBJECT_CLASS_CHECK(ClassType, klass, TYPENAME); }
 201
 202/**
 203 * DECLARE_OBJ_CHECKERS:
 204 * @InstanceType: instance struct name
 205 * @ClassType: class struct name
 206 * @OBJ_NAME: the object name in uppercase with underscore separators
 207 * @TYPENAME: type name
 208 *
 209 * Direct usage of this macro should be avoided, and the complete
 210 * OBJECT_DECLARE_TYPE macro is recommended instead.
 211 *
 212 * This macro will provide the three standard type cast functions for a
 213 * QOM type.
 214 */
 215#define DECLARE_OBJ_CHECKERS(InstanceType, ClassType, OBJ_NAME, TYPENAME) \
 216    DECLARE_INSTANCE_CHECKER(InstanceType, OBJ_NAME, TYPENAME) \
 217    \
 218    DECLARE_CLASS_CHECKERS(ClassType, OBJ_NAME, TYPENAME)
 219
 220/**
 221 * OBJECT_DECLARE_TYPE:
 222 * @InstanceType: instance struct name
 223 * @ClassType: class struct name
 224 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 225 *
 226 * This macro is typically used in a header file, and will:
 227 *
 228 *   - create the typedefs for the object and class structs
 229 *   - register the type for use with g_autoptr
 230 *   - provide three standard type cast functions
 231 *
 232 * The object struct and class struct need to be declared manually.
 233 */
 234#define OBJECT_DECLARE_TYPE(InstanceType, ClassType, MODULE_OBJ_NAME) \
 235    typedef struct InstanceType InstanceType; \
 236    typedef struct ClassType ClassType; \
 237    \
 238    G_DEFINE_AUTOPTR_CLEANUP_FUNC(InstanceType, object_unref) \
 239    \
 240    DECLARE_OBJ_CHECKERS(InstanceType, ClassType, \
 241                         MODULE_OBJ_NAME, TYPE_##MODULE_OBJ_NAME)
 242
 243/**
 244 * OBJECT_DECLARE_SIMPLE_TYPE:
 245 * @InstanceType: instance struct name
 246 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 247 *
 248 * This does the same as OBJECT_DECLARE_TYPE(), but with no class struct
 249 * declared.
 250 *
 251 * This macro should be used unless the class struct needs to have
 252 * virtual methods declared.
 253 */
 254#define OBJECT_DECLARE_SIMPLE_TYPE(InstanceType, MODULE_OBJ_NAME) \
 255    typedef struct InstanceType InstanceType; \
 256    \
 257    G_DEFINE_AUTOPTR_CLEANUP_FUNC(InstanceType, object_unref) \
 258    \
 259    DECLARE_INSTANCE_CHECKER(InstanceType, MODULE_OBJ_NAME, TYPE_##MODULE_OBJ_NAME)
 260
 261
 262/**
 263 * DO_OBJECT_DEFINE_TYPE_EXTENDED:
 264 * @ModuleObjName: the object name with initial caps
 265 * @module_obj_name: the object name in lowercase with underscore separators
 266 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 267 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 268 *                          separators
 269 * @ABSTRACT: boolean flag to indicate whether the object can be instantiated
 270 * @CLASS_SIZE: size of the type's class
 271 * @...: list of initializers for "InterfaceInfo" to declare implemented interfaces
 272 *
 273 * This is the base macro used to implement all the OBJECT_DEFINE_*
 274 * macros. It should never be used directly in a source file.
 275 */
 276#define DO_OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 277                                       MODULE_OBJ_NAME, \
 278                                       PARENT_MODULE_OBJ_NAME, \
 279                                       ABSTRACT, CLASS_SIZE, ...) \
 280    static void \
 281    module_obj_name##_finalize(Object *obj); \
 282    static void \
 283    module_obj_name##_class_init(ObjectClass *oc, const void *data); \
 284    static void \
 285    module_obj_name##_init(Object *obj); \
 286    \
 287    static const TypeInfo module_obj_name##_info = { \
 288        .parent = TYPE_##PARENT_MODULE_OBJ_NAME, \
 289        .name = TYPE_##MODULE_OBJ_NAME, \
 290        .instance_size = sizeof(ModuleObjName), \
 291        .instance_align = __alignof__(ModuleObjName), \
 292        .instance_init = module_obj_name##_init, \
 293        .instance_finalize = module_obj_name##_finalize, \
 294        .class_size = CLASS_SIZE, \
 295        .class_init = module_obj_name##_class_init, \
 296        .abstract = ABSTRACT, \
 297        .interfaces = (const InterfaceInfo[]) { __VA_ARGS__ } , \
 298    }; \
 299    \
 300    static void \
 301    module_obj_name##_register_types(void) \
 302    { \
 303        type_register_static(&module_obj_name##_info); \
 304    } \
 305    type_init(module_obj_name##_register_types);
 306
 307/**
 308 * OBJECT_DEFINE_TYPE_EXTENDED:
 309 * @ModuleObjName: the object name with initial caps
 310 * @module_obj_name: the object name in lowercase with underscore separators
 311 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 312 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 313 *                          separators
 314 * @ABSTRACT: boolean flag to indicate whether the object can be instantiated
 315 * @...: list of initializers for "InterfaceInfo" to declare implemented interfaces
 316 *
 317 * This macro is typically used in a source file, and will:
 318 *
 319 *   - declare prototypes for _finalize, _class_init and _init methods
 320 *   - declare the TypeInfo struct instance
 321 *   - provide the constructor to register the type
 322 *
 323 * After using this macro, implementations of the _finalize, _class_init,
 324 * and _init methods need to be written. Any of these can be zero-line
 325 * no-op impls if no special logic is required for a given type.
 326 *
 327 * This macro should rarely be used, instead one of the more specialized
 328 * macros is usually a better choice.
 329 */
 330#define OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 331                                    MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 332                                    ABSTRACT, ...) \
 333    DO_OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 334                                   MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 335                                   ABSTRACT, sizeof(ModuleObjName##Class), \
 336                                   __VA_ARGS__)
 337
 338/**
 339 * OBJECT_DEFINE_TYPE:
 340 * @ModuleObjName: the object name with initial caps
 341 * @module_obj_name: the object name in lowercase with underscore separators
 342 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 343 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 344 *                          separators
 345 *
 346 * This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
 347 * for the common case of a non-abstract type, without any interfaces.
 348 */
 349#define OBJECT_DEFINE_TYPE(ModuleObjName, module_obj_name, MODULE_OBJ_NAME, \
 350                           PARENT_MODULE_OBJ_NAME) \
 351    OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 352                                MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 353                                false, { NULL })
 354
 355/**
 356 * OBJECT_DEFINE_TYPE_WITH_INTERFACES:
 357 * @ModuleObjName: the object name with initial caps
 358 * @module_obj_name: the object name in lowercase with underscore separators
 359 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 360 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 361 *                          separators
 362 * @...: list of initializers for "InterfaceInfo" to declare implemented interfaces
 363 *
 364 * This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
 365 * for the common case of a non-abstract type, with one or more implemented
 366 * interfaces.
 367 *
 368 * Note when passing the list of interfaces, be sure to include the final
 369 * NULL entry, e.g.  { TYPE_USER_CREATABLE }, { NULL }
 370 */
 371#define OBJECT_DEFINE_TYPE_WITH_INTERFACES(ModuleObjName, module_obj_name, \
 372                                           MODULE_OBJ_NAME, \
 373                                           PARENT_MODULE_OBJ_NAME, ...) \
 374    OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 375                                MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 376                                false, __VA_ARGS__)
 377
 378/**
 379 * OBJECT_DEFINE_ABSTRACT_TYPE:
 380 * @ModuleObjName: the object name with initial caps
 381 * @module_obj_name: the object name in lowercase with underscore separators
 382 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 383 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 384 *                          separators
 385 *
 386 * This is a specialization of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable
 387 * for defining an abstract type, without any interfaces.
 388 */
 389#define OBJECT_DEFINE_ABSTRACT_TYPE(ModuleObjName, module_obj_name, \
 390                                    MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME) \
 391    OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 392                                MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 393                                true, { NULL })
 394
 395/**
 396 * OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES:
 397 * @ModuleObjName: the object name with initial caps
 398 * @module_obj_name: the object name in lowercase with underscore separators
 399 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 400 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 401 *                          separators
 402 *
 403 * This is a variant of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable for
 404 * the case of a non-abstract type, with interfaces, and with no requirement
 405 * for a class struct.
 406 */
 407#define OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(ModuleObjName, \
 408                                                  module_obj_name, \
 409                                                  MODULE_OBJ_NAME, \
 410                                                  PARENT_MODULE_OBJ_NAME, ...) \
 411    DO_OBJECT_DEFINE_TYPE_EXTENDED(ModuleObjName, module_obj_name, \
 412                                   MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, \
 413                                   false, 0, __VA_ARGS__)
 414
 415/**
 416 * OBJECT_DEFINE_SIMPLE_TYPE:
 417 * @ModuleObjName: the object name with initial caps
 418 * @module_obj_name: the object name in lowercase with underscore separators
 419 * @MODULE_OBJ_NAME: the object name in uppercase with underscore separators
 420 * @PARENT_MODULE_OBJ_NAME: the parent object name in uppercase with underscore
 421 *                          separators
 422 *
 423 * This is a variant of OBJECT_DEFINE_TYPE_EXTENDED, which is suitable for
 424 * the common case of a non-abstract type, without any interfaces, and with
 425 * no requirement for a class struct. If you declared your type with
 426 * OBJECT_DECLARE_SIMPLE_TYPE then this is probably the right choice for
 427 * defining it.
 428 */
 429#define OBJECT_DEFINE_SIMPLE_TYPE(ModuleObjName, module_obj_name, \
 430                                  MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME) \
 431    OBJECT_DEFINE_SIMPLE_TYPE_WITH_INTERFACES(ModuleObjName, module_obj_name, \
 432        MODULE_OBJ_NAME, PARENT_MODULE_OBJ_NAME, { NULL })
 433
 434/**
 435 * struct TypeInfo:
 436 * @name: The name of the type.
 437 * @parent: The name of the parent type.
 438 * @instance_size: The size of the object (derivative of #Object).  If
 439 *   @instance_size is 0, then the size of the object will be the size of the
 440 *   parent object.
 441 * @instance_align: The required alignment of the object.  If @instance_align
 442 *   is 0, then normal malloc alignment is sufficient; if non-zero, then we
 443 *   must use qemu_memalign for allocation.
 444 * @instance_init: This function is called to initialize an object.  The parent
 445 *   class will have already been initialized so the type is only responsible
 446 *   for initializing its own members.
 447 * @instance_post_init: This function is called to finish initialization of
 448 *   an object, after all @instance_init functions were called, as well as
 449 *   @instance_post_init functions for the parent classes.
 450 * @instance_finalize: This function is called during object destruction.  This
 451 *   is called before the parent @instance_finalize function has been called.
 452 *   An object should only free the members that are unique to its type in this
 453 *   function.
 454 * @abstract: If this field is true, then the class is considered abstract and
 455 *   cannot be directly instantiated.
 456 * @class_size: The size of the class object (derivative of #ObjectClass)
 457 *   for this object.  If @class_size is 0, then the size of the class will be
 458 *   assumed to be the size of the parent class.  This allows a type to avoid
 459 *   implementing an explicit class type if they are not adding additional
 460 *   virtual functions.
 461 * @class_init: This function is called after all parent class initialization
 462 *   has occurred to allow a class to set its default virtual method pointers.
 463 *   This is also the function to use to override virtual methods from a parent
 464 *   class.
 465 * @class_base_init: This function is called for all base classes after all
 466 *   parent class initialization has occurred, but before the class itself
 467 *   is initialized.  This is the function to use to undo the effects of
 468 *   memcpy from the parent class to the descendants.
 469 * @class_data: Data to pass to the @class_init,
 470 *   @class_base_init. This can be useful when building dynamic
 471 *   classes.
 472 * @interfaces: The list of interfaces associated with this type.  This
 473 *   should point to a static array that's terminated with a zero filled
 474 *   element.
 475 */
 476struct TypeInfo
 477{
 478    const char *name;
 479    const char *parent;
 480
 481    size_t instance_size;
 482    size_t instance_align;
 483    void (*instance_init)(Object *obj);
 484    void (*instance_post_init)(Object *obj);
 485    void (*instance_finalize)(Object *obj);
 486
 487    bool abstract;
 488    size_t class_size;
 489
 490    void (*class_init)(ObjectClass *klass, const void *data);
 491    void (*class_base_init)(ObjectClass *klass, const void *data);
 492    const void *class_data;
 493
 494    const InterfaceInfo *interfaces;
 495};
 496
 497/**
 498 * OBJECT:
 499 * @obj: A derivative of #Object
 500 *
 501 * Converts an object to a #Object.  Since all objects are #Objects,
 502 * this function will always succeed.
 503 */
 504#define OBJECT(obj) \
 505    ((Object *)(obj))
 506
 507/**
 508 * OBJECT_CLASS:
 509 * @class: A derivative of #ObjectClass.
 510 *
 511 * Converts a class to an #ObjectClass.  Since all objects are #Objects,
 512 * this function will always succeed.
 513 */
 514#define OBJECT_CLASS(class) \
 515    ((ObjectClass *)(class))
 516
 517/**
 518 * OBJECT_CHECK:
 519 * @type: The C type to use for the return value.
 520 * @obj: A derivative of @type to cast.
 521 * @name: The QOM typename of @type
 522 *
 523 * A type safe version of @object_dynamic_cast_assert.  Typically each class
 524 * will define a macro based on this type to perform type safe dynamic_casts to
 525 * this object type.
 526 *
 527 * If an invalid object is passed to this function, a run time assert will be
 528 * generated.
 529 */
 530#define OBJECT_CHECK(type, obj, name) \
 531    ((type *)object_dynamic_cast_assert(OBJECT(obj), (name), \
 532                                        __FILE__, __LINE__, __func__))
 533
 534/**
 535 * OBJECT_CLASS_CHECK:
 536 * @class_type: The C type to use for the return value.
 537 * @class: A derivative class of @class_type to cast.
 538 * @name: the QOM typename of @class_type.
 539 *
 540 * A type safe version of @object_class_dynamic_cast_assert.  This macro is
 541 * typically wrapped by each type to perform type safe casts of a class to a
 542 * specific class type.
 543 */
 544#define OBJECT_CLASS_CHECK(class_type, class, name) \
 545    ((class_type *)object_class_dynamic_cast_assert(OBJECT_CLASS(class), (name), \
 546                                               __FILE__, __LINE__, __func__))
 547
 548/**
 549 * OBJECT_GET_CLASS:
 550 * @class: The C type to use for the return value.
 551 * @obj: The object to obtain the class for.
 552 * @name: The QOM typename of @obj.
 553 *
 554 * This function will return a specific class for a given object.  Its generally
 555 * used by each type to provide a type safe macro to get a specific class type
 556 * from an object.
 557 */
 558#define OBJECT_GET_CLASS(class, obj, name) \
 559    OBJECT_CLASS_CHECK(class, object_get_class(OBJECT(obj)), name)
 560
 561/**
 562 * struct InterfaceInfo:
 563 * @type: The name of the interface.
 564 *
 565 * The information associated with an interface.
 566 */
 567struct InterfaceInfo {
 568    const char *type;
 569};
 570
 571/**
 572 * struct InterfaceClass:
 573 * @parent_class: the base class
 574 *
 575 * The class for all interfaces.  Subclasses of this class should only add
 576 * virtual methods.
 577 *
 578 * Note that most of the fields of ObjectClass are unused (all except
 579 * "type", in fact).  They are only present in InterfaceClass to allow
 580 * @object_class_dynamic_cast to work with both regular classes and interfaces.
 581 */
 582struct InterfaceClass
 583{
 584    ObjectClass parent_class;
 585    /* private: */
 586    Type interface_type;
 587};
 588
 589#define TYPE_INTERFACE "interface"
 590
 591/**
 592 * INTERFACE_CLASS:
 593 * @klass: class to cast from
 594 * Returns: An #InterfaceClass or raise an error if cast is invalid
 595 */
 596#define INTERFACE_CLASS(klass) \
 597    OBJECT_CLASS_CHECK(InterfaceClass, klass, TYPE_INTERFACE)
 598
 599/**
 600 * INTERFACE_CHECK:
 601 * @interface: the type to return
 602 * @obj: the object to convert to an interface
 603 * @name: the interface type name
 604 *
 605 * Returns: @obj casted to @interface if cast is valid, otherwise raise error.
 606 */
 607#define INTERFACE_CHECK(interface, obj, name) \
 608    ((interface *)object_dynamic_cast_assert(OBJECT((obj)), (name), \
 609                                             __FILE__, __LINE__, __func__))
 610
 611/**
 612 * object_new_with_class:
 613 * @klass: The class to instantiate.
 614 *
 615 * This function will initialize a new object using heap allocated memory.
 616 * The returned object has a reference count of 1, and will be freed when
 617 * the last reference is dropped.
 618 *
 619 * Returns: The newly allocated and instantiated object.
 620 */
 621Object *object_new_with_class(ObjectClass *klass);
 622
 623/**
 624 * object_new:
 625 * @typename: The name of the type of the object to instantiate.
 626 *
 627 * This function will initialize a new object using heap allocated memory.
 628 * The returned object has a reference count of 1, and will be freed when
 629 * the last reference is dropped.
 630 *
 631 * Returns: The newly allocated and instantiated object.
 632 */
 633Object *object_new(const char *typename);
 634
 635/**
 636 * object_new_with_props:
 637 * @typename:  The name of the type of the object to instantiate.
 638 * @parent: the parent object
 639 * @id: The unique ID of the object
 640 * @errp: pointer to error object
 641 * @...: list of property names and values
 642 *
 643 * This function will initialize a new object using heap allocated memory.
 644 * The returned object has a reference count of 1, and will be freed when
 645 * the last reference is dropped.
 646 *
 647 * The @id parameter will be used when registering the object as a
 648 * child of @parent in the composition tree.
 649 *
 650 * The variadic parameters are a list of pairs of (propname, propvalue)
 651 * strings. The propname of %NULL indicates the end of the property
 652 * list. If the object implements the user creatable interface, the
 653 * object will be marked complete once all the properties have been
 654 * processed.
 655 *
 656 * .. code-block:: c
 657 *    :caption: Creating an object with properties
 658 *
 659 *      Error *err = NULL;
 660 *      Object *obj;
 661 *
 662 *      obj = object_new_with_props(TYPE_MEMORY_BACKEND_FILE,
 663 *                                  object_get_objects_root(),
 664 *                                  "hostmem0",
 665 *                                  &err,
 666 *                                  "share", "yes",
 667 *                                  "mem-path", "/dev/shm/somefile",
 668 *                                  "prealloc", "yes",
 669 *                                  "size", "1048576",
 670 *                                  NULL);
 671 *
 672 *      if (!obj) {
 673 *        error_reportf_err(err, "Cannot create memory backend: ");
 674 *      }
 675 *
 676 * The returned object will have one stable reference maintained
 677 * for as long as it is present in the object hierarchy.
 678 *
 679 * Returns: The newly allocated, instantiated & initialized object.
 680 */
 681Object *object_new_with_props(const char *typename,
 682                              Object *parent,
 683                              const char *id,
 684                              Error **errp,
 685                              ...) G_GNUC_NULL_TERMINATED;
 686
 687/**
 688 * object_new_with_propv:
 689 * @typename:  The name of the type of the object to instantiate.
 690 * @parent: the parent object
 691 * @id: The unique ID of the object
 692 * @errp: pointer to error object
 693 * @vargs: list of property names and values
 694 *
 695 * See object_new_with_props() for documentation.
 696 */
 697Object *object_new_with_propv(const char *typename,
 698                              Object *parent,
 699                              const char *id,
 700                              Error **errp,
 701                              va_list vargs);
 702
 703bool object_apply_global_props(Object *obj, const GPtrArray *props,
 704                               Error **errp);
 705void object_set_machine_compat_props(GPtrArray *compat_props);
 706void object_set_accelerator_compat_props(GPtrArray *compat_props);
 707void object_register_sugar_prop(const char *driver, const char *prop,
 708                                const char *value, bool optional);
 709void object_apply_compat_props(Object *obj);
 710
 711/**
 712 * object_set_props:
 713 * @obj: the object instance to set properties on
 714 * @errp: pointer to error object
 715 * @...: list of property names and values
 716 *
 717 * This function will set a list of properties on an existing object
 718 * instance.
 719 *
 720 * The variadic parameters are a list of pairs of (propname, propvalue)
 721 * strings. The propname of %NULL indicates the end of the property
 722 * list.
 723 *
 724 * .. code-block:: c
 725 *    :caption: Update an object's properties
 726 *
 727 *      Error *err = NULL;
 728 *      Object *obj = ...get / create object...;
 729 *
 730 *      if (!object_set_props(obj,
 731 *                            &err,
 732 *                            "share", "yes",
 733 *                            "mem-path", "/dev/shm/somefile",
 734 *                            "prealloc", "yes",
 735 *                            "size", "1048576",
 736 *                            NULL)) {
 737 *        error_reportf_err(err, "Cannot set properties: ");
 738 *      }
 739 *
 740 * The returned object will have one stable reference maintained
 741 * for as long as it is present in the object hierarchy.
 742 *
 743 * Returns: %true on success, %false on error.
 744 */
 745bool object_set_props(Object *obj, Error **errp, ...) G_GNUC_NULL_TERMINATED;
 746
 747/**
 748 * object_set_propv:
 749 * @obj: the object instance to set properties on
 750 * @errp: pointer to error object
 751 * @vargs: list of property names and values
 752 *
 753 * See object_set_props() for documentation.
 754 *
 755 * Returns: %true on success, %false on error.
 756 */
 757bool object_set_propv(Object *obj, Error **errp, va_list vargs);
 758
 759/**
 760 * object_initialize:
 761 * @obj: A pointer to the memory to be used for the object.
 762 * @size: The maximum size available at @obj for the object.
 763 * @typename: The name of the type of the object to instantiate.
 764 *
 765 * This function will initialize an object.  The memory for the object should
 766 * have already been allocated.  The returned object has a reference count of 1,
 767 * and will be finalized when the last reference is dropped.
 768 */
 769void object_initialize(void *obj, size_t size, const char *typename);
 770
 771/**
 772 * object_initialize_child_with_props:
 773 * @parentobj: The parent object to add a property to
 774 * @propname: The name of the property
 775 * @childobj: A pointer to the memory to be used for the object.
 776 * @size: The maximum size available at @childobj for the object.
 777 * @type: The name of the type of the object to instantiate.
 778 * @errp: If an error occurs, a pointer to an area to store the error
 779 * @...: list of property names and values
 780 *
 781 * This function will initialize an object. The memory for the object should
 782 * have already been allocated. The object will then be added as child property
 783 * to a parent with object_property_add_child() function. The returned object
 784 * has a reference count of 1 (for the "child<...>" property from the parent),
 785 * so the object will be finalized automatically when the parent gets removed.
 786 *
 787 * The variadic parameters are a list of pairs of (propname, propvalue)
 788 * strings. The propname of %NULL indicates the end of the property list.
 789 * If the object implements the user creatable interface, the object will
 790 * be marked complete once all the properties have been processed.
 791 *
 792 * Returns: %true on success, %false on failure.
 793 */
 794bool object_initialize_child_with_props(Object *parentobj,
 795                             const char *propname,
 796                             void *childobj, size_t size, const char *type,
 797                             Error **errp, ...) G_GNUC_NULL_TERMINATED;
 798
 799/**
 800 * object_initialize_child_with_propsv:
 801 * @parentobj: The parent object to add a property to
 802 * @propname: The name of the property
 803 * @childobj: A pointer to the memory to be used for the object.
 804 * @size: The maximum size available at @childobj for the object.
 805 * @type: The name of the type of the object to instantiate.
 806 * @errp: If an error occurs, a pointer to an area to store the error
 807 * @vargs: list of property names and values
 808 *
 809 * See object_initialize_child() for documentation.
 810 *
 811 * Returns: %true on success, %false on failure.
 812 */
 813bool object_initialize_child_with_propsv(Object *parentobj,
 814                              const char *propname,
 815                              void *childobj, size_t size, const char *type,
 816                              Error **errp, va_list vargs);
 817
 818/**
 819 * object_initialize_child:
 820 * @parent: The parent object to add a property to
 821 * @propname: The name of the property
 822 * @child: A precisely typed pointer to the memory to be used for the
 823 * object.
 824 * @type: The name of the type of the object to instantiate.
 825 *
 826 * This is like::
 827 *
 828 *   object_initialize_child_with_props(parent, propname,
 829 *                                      child, sizeof(*child), type,
 830 *                                      &error_abort, NULL)
 831 */
 832#define object_initialize_child(parent, propname, child, type)          \
 833    object_initialize_child_internal((parent), (propname),              \
 834                                     (child), sizeof(*(child)), (type))
 835void object_initialize_child_internal(Object *parent, const char *propname,
 836                                      void *child, size_t size,
 837                                      const char *type);
 838
 839/**
 840 * object_dynamic_cast:
 841 * @obj: The object to cast.
 842 * @typename: The @typename to cast to.
 843 *
 844 * This function will determine if @obj is-a @typename.  @obj can refer to an
 845 * object or an interface associated with an object.
 846 *
 847 * Returns: This function returns @obj on success or #NULL on failure.
 848 */
 849Object *object_dynamic_cast(Object *obj, const char *typename);
 850
 851/**
 852 * object_dynamic_cast_assert:
 853 * @obj: The object to cast.
 854 * @typename: The @typename to cast to.
 855 * @file: Source code file where function was called
 856 * @line: Source code line where function was called
 857 * @func: Name of function where this function was called
 858 *
 859 * See object_dynamic_cast() for a description of the parameters of this
 860 * function.  The only difference in behavior is that this function asserts
 861 * instead of returning #NULL on failure if QOM cast debugging is enabled.
 862 * This function is not meant to be called directly, but only through
 863 * the wrapper macro OBJECT_CHECK.
 864 */
 865Object *object_dynamic_cast_assert(Object *obj, const char *typename,
 866                                   const char *file, int line, const char *func);
 867
 868/**
 869 * object_get_class:
 870 * @obj: A derivative of #Object
 871 *
 872 * Returns: The #ObjectClass of the type associated with @obj.
 873 */
 874ObjectClass *object_get_class(Object *obj);
 875
 876/**
 877 * object_get_typename:
 878 * @obj: A derivative of #Object.
 879 *
 880 * Returns: The QOM typename of @obj.
 881 */
 882const char *object_get_typename(const Object *obj);
 883
 884/**
 885 * type_register_static:
 886 * @info: The #TypeInfo of the new type.
 887 *
 888 * Returns: the new #Type.
 889 */
 890Type type_register_static(const TypeInfo *info);
 891
 892/**
 893 * type_register_static_array:
 894 * @infos: The array of the new type #TypeInfo structures.
 895 * @nr_infos: number of entries in @infos
 896 *
 897 * @infos and all of the strings it points to should exist for the life time
 898 * that the type is registered.
 899 */
 900void type_register_static_array(const TypeInfo *infos, int nr_infos);
 901
 902/**
 903 * DEFINE_TYPES:
 904 * @type_array: The array containing #TypeInfo structures to register
 905 *
 906 * @type_array should be static constant that exists for the life time
 907 * that the type is registered.
 908 */
 909#define DEFINE_TYPES(type_array)                                            \
 910static void do_qemu_init_ ## type_array(void)                               \
 911{                                                                           \
 912    type_register_static_array(type_array, ARRAY_SIZE(type_array));         \
 913}                                                                           \
 914type_init(do_qemu_init_ ## type_array)
 915
 916/**
 917 * type_print_class_properties:
 918 * @type: a QOM class name
 919 *
 920 * Print the object's class properties to stdout or the monitor.
 921 * Return whether an object was found.
 922 */
 923bool type_print_class_properties(const char *type);
 924
 925/**
 926 * object_set_properties_from_keyval:
 927 * @obj: a QOM object
 928 * @qdict: a dictionary with the properties to be set
 929 * @from_json: true if leaf values of @qdict are typed, false if they
 930 * are strings
 931 * @errp: pointer to error object
 932 *
 933 * For each key in the dictionary, parse the value string if needed,
 934 * then set the corresponding property in @obj.
 935 */
 936void object_set_properties_from_keyval(Object *obj, const QDict *qdict,
 937                                       bool from_json, Error **errp);
 938
 939/**
 940 * object_class_dynamic_cast_assert:
 941 * @klass: The #ObjectClass to attempt to cast.
 942 * @typename: The QOM typename of the class to cast to.
 943 * @file: Source code file where function was called
 944 * @line: Source code line where function was called
 945 * @func: Name of function where this function was called
 946 *
 947 * See object_class_dynamic_cast() for a description of the parameters
 948 * of this function.  The only difference in behavior is that this function
 949 * asserts instead of returning #NULL on failure if QOM cast debugging is
 950 * enabled.  This function is not meant to be called directly, but only through
 951 * the wrapper macro OBJECT_CLASS_CHECK.
 952 */
 953ObjectClass *object_class_dynamic_cast_assert(ObjectClass *klass,
 954                                              const char *typename,
 955                                              const char *file, int line,
 956                                              const char *func);
 957
 958/**
 959 * object_class_dynamic_cast:
 960 * @klass: The #ObjectClass to attempt to cast.
 961 * @typename: The QOM typename of the class to cast to.
 962 *
 963 * Returns: If @typename is a class, this function returns @klass if
 964 * @typename is a subtype of @klass, else returns #NULL.
 965 *
 966 * If @typename is an interface, this function returns the interface
 967 * definition for @klass if @klass implements it unambiguously; #NULL
 968 * is returned if @klass does not implement the interface or if multiple
 969 * classes or interfaces on the hierarchy leading to @klass implement
 970 * it.  (FIXME: perhaps this can be detected at type definition time?)
 971 */
 972ObjectClass *object_class_dynamic_cast(ObjectClass *klass,
 973                                       const char *typename);
 974
 975/**
 976 * object_class_get_parent:
 977 * @klass: The class to obtain the parent for.
 978 *
 979 * Returns: The parent for @klass or %NULL if none.
 980 */
 981ObjectClass *object_class_get_parent(ObjectClass *klass);
 982
 983/**
 984 * object_class_get_name:
 985 * @klass: The class to obtain the QOM typename for.
 986 *
 987 * Returns: The QOM typename for @klass.
 988 */
 989const char *object_class_get_name(ObjectClass *klass);
 990
 991/**
 992 * object_class_is_abstract:
 993 * @klass: The class to obtain the abstractness for.
 994 *
 995 * Returns: %true if @klass is abstract, %false otherwise.
 996 */
 997bool object_class_is_abstract(ObjectClass *klass);
 998
 999/**
1000 * object_class_by_name:
1001 * @typename: The QOM typename to obtain the class for.
1002 *
1003 * Returns: The class for @typename or %NULL if not found.
1004 */
1005ObjectClass *object_class_by_name(const char *typename);
1006
1007/**
1008 * module_object_class_by_name:
1009 * @typename: The QOM typename to obtain the class for.
1010 *
1011 * For objects which might be provided by a module.  Behaves like
1012 * object_class_by_name, but additionally tries to load the module
1013 * needed in case the class is not available.
1014 *
1015 * Returns: The class for @typename or %NULL if not found.
1016 */
1017ObjectClass *module_object_class_by_name(const char *typename);
1018
1019void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
1020                          const char *implements_type, bool include_abstract,
1021                          void *opaque);
1022
1023/**
1024 * object_class_get_list:
1025 * @implements_type: The type to filter for, including its derivatives.
1026 * @include_abstract: Whether to include abstract classes.
1027 *
1028 * Returns: A singly-linked list of the classes in reverse hashtable order.
1029 */
1030GSList *object_class_get_list(const char *implements_type,
1031                              bool include_abstract);
1032
1033/**
1034 * object_class_get_list_sorted:
1035 * @implements_type: The type to filter for, including its derivatives.
1036 * @include_abstract: Whether to include abstract classes.
1037 *
1038 * Returns: A singly-linked list of the classes in alphabetical
1039 * case-insensitive order.
1040 */
1041GSList *object_class_get_list_sorted(const char *implements_type,
1042                              bool include_abstract);
1043
1044/**
1045 * object_ref:
1046 * @obj: the object
1047 *
1048 * Increase the reference count of a object.  A object cannot be freed as long
1049 * as its reference count is greater than zero.
1050 * Returns: @obj
1051 */
1052Object *object_ref(void *obj);
1053
1054/**
1055 * object_unref:
1056 * @obj: the object
1057 *
1058 * Decrease the reference count of a object.  A object cannot be freed as long
1059 * as its reference count is greater than zero.
1060 */
1061void object_unref(void *obj);
1062
1063/**
1064 * object_property_try_add:
1065 * @obj: the object to add a property to
1066 * @name: the name of the property.  This can contain any character except for
1067 *  a forward slash.  In general, you should use hyphens '-' instead of
1068 *  underscores '_' when naming properties.
1069 * @type: the type name of the property.  This namespace is pretty loosely
1070 *   defined.  Sub namespaces are constructed by using a prefix and then
1071 *   to angle brackets.  For instance, the type 'virtio-net-pci' in the
1072 *   'link' namespace would be 'link<virtio-net-pci>'.
1073 * @get: The getter to be called to read a property.  If this is NULL, then
1074 *   the property cannot be read.
1075 * @set: the setter to be called to write a property.  If this is NULL,
1076 *   then the property cannot be written.
1077 * @release: called when the property is removed from the object.  This is
1078 *   meant to allow a property to free its opaque upon object
1079 *   destruction.  This may be NULL.
1080 * @opaque: an opaque pointer to pass to the callbacks for the property
1081 * @errp: pointer to error object
1082 *
1083 * Returns: The #ObjectProperty; this can be used to set the @resolve
1084 * callback for child and link properties.
1085 */
1086ObjectProperty *object_property_try_add(Object *obj, const char *name,
1087                                        const char *type,
1088                                        ObjectPropertyAccessor *get,
1089                                        ObjectPropertyAccessor *set,
1090                                        ObjectPropertyRelease *release,
1091                                        void *opaque, Error **errp);
1092
1093/**
1094 * object_property_add:
1095 * Same as object_property_try_add() with @errp hardcoded to
1096 * &error_abort.
1097 *
1098 * @obj: the object to add a property to
1099 * @name: the name of the property.  This can contain any character except for
1100 *  a forward slash.  In general, you should use hyphens '-' instead of
1101 *  underscores '_' when naming properties.
1102 * @type: the type name of the property.  This namespace is pretty loosely
1103 *   defined.  Sub namespaces are constructed by using a prefix and then
1104 *   to angle brackets.  For instance, the type 'virtio-net-pci' in the
1105 *   'link' namespace would be 'link<virtio-net-pci>'.
1106 * @get: The getter to be called to read a property.  If this is NULL, then
1107 *   the property cannot be read.
1108 * @set: the setter to be called to write a property.  If this is NULL,
1109 *   then the property cannot be written.
1110 * @release: called when the property is removed from the object.  This is
1111 *   meant to allow a property to free its opaque upon object
1112 *   destruction.  This may be NULL.
1113 * @opaque: an opaque pointer to pass to the callbacks for the property
1114 */
1115ObjectProperty *object_property_add(Object *obj, const char *name,
1116                                    const char *type,
1117                                    ObjectPropertyAccessor *get,
1118                                    ObjectPropertyAccessor *set,
1119                                    ObjectPropertyRelease *release,
1120                                    void *opaque);
1121
1122void object_property_del(Object *obj, const char *name);
1123
1124ObjectProperty *object_class_property_add(ObjectClass *klass, const char *name,
1125                                          const char *type,
1126                                          ObjectPropertyAccessor *get,
1127                                          ObjectPropertyAccessor *set,
1128                                          ObjectPropertyRelease *release,
1129                                          void *opaque);
1130
1131/**
1132 * object_property_set_default_bool:
1133 * @prop: the property to set
1134 * @value: the value to be written to the property
1135 *
1136 * Set the property default value.
1137 */
1138void object_property_set_default_bool(ObjectProperty *prop, bool value);
1139
1140/**
1141 * object_property_set_default_str:
1142 * @prop: the property to set
1143 * @value: the value to be written to the property
1144 *
1145 * Set the property default value.
1146 */
1147void object_property_set_default_str(ObjectProperty *prop, const char *value);
1148
1149/**
1150 * object_property_set_default_list:
1151 * @prop: the property to set
1152 *
1153 * Set the property default value to be an empty list.
1154 */
1155void object_property_set_default_list(ObjectProperty *prop);
1156
1157/**
1158 * object_property_set_default_int:
1159 * @prop: the property to set
1160 * @value: the value to be written to the property
1161 *
1162 * Set the property default value.
1163 */
1164void object_property_set_default_int(ObjectProperty *prop, int64_t value);
1165
1166/**
1167 * object_property_set_default_uint:
1168 * @prop: the property to set
1169 * @value: the value to be written to the property
1170 *
1171 * Set the property default value.
1172 */
1173void object_property_set_default_uint(ObjectProperty *prop, uint64_t value);
1174
1175/**
1176 * object_property_find:
1177 * @obj: the object
1178 * @name: the name of the property
1179 *
1180 * Look up a property for an object.
1181 *
1182 * Return its #ObjectProperty if found, or NULL.
1183 */
1184ObjectProperty *object_property_find(Object *obj, const char *name);
1185
1186/**
1187 * object_property_find_err:
1188 * @obj: the object
1189 * @name: the name of the property
1190 * @errp: returns an error if this function fails
1191 *
1192 * Look up a property for an object.
1193 *
1194 * Return its #ObjectProperty if found, or NULL.
1195 */
1196ObjectProperty *object_property_find_err(Object *obj,
1197                                         const char *name,
1198                                         Error **errp);
1199
1200/**
1201 * object_class_property_find:
1202 * @klass: the object class
1203 * @name: the name of the property
1204 *
1205 * Look up a property for an object class.
1206 *
1207 * Return its #ObjectProperty if found, or NULL.
1208 */
1209ObjectProperty *object_class_property_find(ObjectClass *klass,
1210                                           const char *name);
1211
1212/**
1213 * object_class_property_find_err:
1214 * @klass: the object class
1215 * @name: the name of the property
1216 * @errp: returns an error if this function fails
1217 *
1218 * Look up a property for an object class.
1219 *
1220 * Return its #ObjectProperty if found, or NULL.
1221 */
1222ObjectProperty *object_class_property_find_err(ObjectClass *klass,
1223                                               const char *name,
1224                                               Error **errp);
1225
1226typedef struct ObjectPropertyIterator {
1227    ObjectClass *nextclass;
1228    GHashTableIter iter;
1229} ObjectPropertyIterator;
1230
1231/**
1232 * object_property_iter_init:
1233 * @iter: the iterator instance
1234 * @obj: the object
1235 *
1236 * Initializes an iterator for traversing all properties
1237 * registered against an object instance, its class and all parent classes.
1238 *
1239 * It is forbidden to modify the property list while iterating,
1240 * whether removing or adding properties.
1241 *
1242 * Typical usage pattern would be
1243 *
1244 * .. code-block:: c
1245 *    :caption: Using object property iterators
1246 *
1247 *      ObjectProperty *prop;
1248 *      ObjectPropertyIterator iter;
1249 *
1250 *      object_property_iter_init(&iter, obj);
1251 *      while ((prop = object_property_iter_next(&iter))) {
1252 *        ... do something with prop ...
1253 *      }
1254 */
1255void object_property_iter_init(ObjectPropertyIterator *iter,
1256                               Object *obj);
1257
1258/**
1259 * object_class_property_iter_init:
1260 * @iter: the iterator instance
1261 * @klass: the class
1262 *
1263 * Initializes an iterator for traversing all properties
1264 * registered against an object class and all parent classes.
1265 *
1266 * It is forbidden to modify the property list while iterating,
1267 * whether removing or adding properties.
1268 *
1269 * This can be used on abstract classes as it does not create a temporary
1270 * instance.
1271 */
1272void object_class_property_iter_init(ObjectPropertyIterator *iter,
1273                                     ObjectClass *klass);
1274
1275/**
1276 * object_property_iter_next:
1277 * @iter: the iterator instance
1278 *
1279 * Return the next available property. If no further properties
1280 * are available, a %NULL value will be returned and the @iter
1281 * pointer should not be used again after this point without
1282 * re-initializing it.
1283 *
1284 * Returns: the next property, or %NULL when all properties
1285 * have been traversed.
1286 */
1287ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter);
1288
1289void object_unparent(Object *obj);
1290
1291/**
1292 * object_property_get:
1293 * @obj: the object
1294 * @name: the name of the property
1295 * @v: the visitor that will receive the property value.  This should be an
1296 *   Output visitor and the data will be written with @name as the name.
1297 * @errp: returns an error if this function fails
1298 *
1299 * Reads a property from a object.
1300 *
1301 * Returns: %true on success, %false on failure.
1302 */
1303bool object_property_get(Object *obj, const char *name, Visitor *v,
1304                         Error **errp);
1305
1306/**
1307 * object_property_set_str:
1308 * @obj: the object
1309 * @name: the name of the property
1310 * @value: the value to be written to the property
1311 * @errp: returns an error if this function fails
1312 *
1313 * Writes a string value to a property.
1314 *
1315 * Returns: %true on success, %false on failure.
1316 */
1317bool object_property_set_str(Object *obj, const char *name,
1318                             const char *value, Error **errp);
1319
1320/**
1321 * object_property_get_str:
1322 * @obj: the object
1323 * @name: the name of the property
1324 * @errp: returns an error if this function fails
1325 *
1326 * Returns: the value of the property, converted to a C string, or NULL if
1327 * an error occurs (including when the property value is not a string).
1328 * The caller should free the string.
1329 */
1330char *object_property_get_str(Object *obj, const char *name,
1331                              Error **errp);
1332
1333/**
1334 * object_property_set_link:
1335 * @obj: the object
1336 * @name: the name of the property
1337 * @value: the value to be written to the property
1338 * @errp: returns an error if this function fails
1339 *
1340 * Writes an object's canonical path to a property.
1341 *
1342 * If the link property was created with
1343 * %OBJ_PROP_LINK_STRONG bit, the old target object is
1344 * unreferenced, and a reference is added to the new target object.
1345 *
1346 * Returns: %true on success, %false on failure.
1347 */
1348bool object_property_set_link(Object *obj, const char *name,
1349                              Object *value, Error **errp);
1350
1351/**
1352 * object_property_get_link:
1353 * @obj: the object
1354 * @name: the name of the property
1355 * @errp: returns an error if this function fails
1356 *
1357 * Returns: the value of the property, resolved from a path to an Object,
1358 * or NULL if an error occurs (including when the property value is not a
1359 * string or not a valid object path).
1360 */
1361Object *object_property_get_link(Object *obj, const char *name,
1362                                 Error **errp);
1363
1364/**
1365 * object_property_set_bool:
1366 * @obj: the object
1367 * @name: the name of the property
1368 * @value: the value to be written to the property
1369 * @errp: returns an error if this function fails
1370 *
1371 * Writes a bool value to a property.
1372 *
1373 * Returns: %true on success, %false on failure.
1374 */
1375bool object_property_set_bool(Object *obj, const char *name,
1376                              bool value, Error **errp);
1377
1378/**
1379 * object_property_get_bool:
1380 * @obj: the object
1381 * @name: the name of the property
1382 * @errp: returns an error if this function fails
1383 *
1384 * Returns: the value of the property, converted to a boolean, or false if
1385 * an error occurs (including when the property value is not a bool).
1386 */
1387bool object_property_get_bool(Object *obj, const char *name,
1388                              Error **errp);
1389
1390/**
1391 * object_property_set_int:
1392 * @obj: the object
1393 * @name: the name of the property
1394 * @value: the value to be written to the property
1395 * @errp: returns an error if this function fails
1396 *
1397 * Writes an integer value to a property.
1398 *
1399 * Returns: %true on success, %false on failure.
1400 */
1401bool object_property_set_int(Object *obj, const char *name,
1402                             int64_t value, Error **errp);
1403
1404/**
1405 * object_property_get_int:
1406 * @obj: the object
1407 * @name: the name of the property
1408 * @errp: returns an error if this function fails
1409 *
1410 * Returns: the value of the property, converted to an integer, or -1 if
1411 * an error occurs (including when the property value is not an integer).
1412 */
1413int64_t object_property_get_int(Object *obj, const char *name,
1414                                Error **errp);
1415
1416/**
1417 * object_property_set_uint:
1418 * @obj: the object
1419 * @name: the name of the property
1420 * @value: the value to be written to the property
1421 * @errp: returns an error if this function fails
1422 *
1423 * Writes an unsigned integer value to a property.
1424 *
1425 * Returns: %true on success, %false on failure.
1426 */
1427bool object_property_set_uint(Object *obj, const char *name,
1428                              uint64_t value, Error **errp);
1429
1430/**
1431 * object_property_get_uint:
1432 * @obj: the object
1433 * @name: the name of the property
1434 * @errp: returns an error if this function fails
1435 *
1436 * Returns: the value of the property, converted to an unsigned integer, or 0
1437 * an error occurs (including when the property value is not an integer).
1438 */
1439uint64_t object_property_get_uint(Object *obj, const char *name,
1440                                  Error **errp);
1441
1442/**
1443 * object_property_get_enum:
1444 * @obj: the object
1445 * @name: the name of the property
1446 * @typename: the name of the enum data type
1447 * @errp: returns an error if this function fails
1448 *
1449 * Returns: the value of the property, converted to an integer (which
1450 * can't be negative), or -1 on error (including when the property
1451 * value is not an enum).
1452 */
1453int object_property_get_enum(Object *obj, const char *name,
1454                             const char *typename, Error **errp);
1455
1456/**
1457 * object_property_set:
1458 * @obj: the object
1459 * @name: the name of the property
1460 * @v: the visitor that will be used to write the property value.  This should
1461 *   be an Input visitor and the data will be first read with @name as the
1462 *   name and then written as the property value.
1463 * @errp: returns an error if this function fails
1464 *
1465 * Writes a property to a object.
1466 *
1467 * Returns: %true on success, %false on failure.
1468 */
1469bool object_property_set(Object *obj, const char *name, Visitor *v,
1470                         Error **errp);
1471
1472/**
1473 * object_property_parse:
1474 * @obj: the object
1475 * @name: the name of the property
1476 * @string: the string that will be used to parse the property value.
1477 * @errp: returns an error if this function fails
1478 *
1479 * Parses a string and writes the result into a property of an object.
1480 *
1481 * Returns: %true on success, %false on failure.
1482 */
1483bool object_property_parse(Object *obj, const char *name,
1484                           const char *string, Error **errp);
1485
1486/**
1487 * object_property_print:
1488 * @obj: the object
1489 * @name: the name of the property
1490 * @human: if true, print for human consumption
1491 * @errp: returns an error if this function fails
1492 *
1493 * Returns a string representation of the value of the property.  The
1494 * caller shall free the string.
1495 */
1496char *object_property_print(Object *obj, const char *name, bool human,
1497                            Error **errp);
1498
1499/**
1500 * object_property_get_type:
1501 * @obj: the object
1502 * @name: the name of the property
1503 * @errp: returns an error if this function fails
1504 *
1505 * Returns:  The type name of the property.
1506 */
1507const char *object_property_get_type(Object *obj, const char *name,
1508                                     Error **errp);
1509
1510/**
1511 * object_get_root:
1512 *
1513 * Returns: the root object of the composition tree
1514 */
1515Object *object_get_root(void);
1516
1517/**
1518 * object_get_container:
1519 * @name: the name of container to lookup
1520 *
1521 * Lookup a root level container.
1522 *
1523 * Returns: the container with @name.
1524 */
1525Object *object_get_container(const char *name);
1526
1527
1528/**
1529 * object_get_objects_root:
1530 *
1531 * Get the container object that holds user created
1532 * object instances. This is the object at path
1533 * "/objects"
1534 *
1535 * Returns: the user object container
1536 */
1537Object *object_get_objects_root(void);
1538
1539/**
1540 * object_get_internal_root:
1541 *
1542 * Get the container object that holds internally used object
1543 * instances.  Any object which is put into this container must not be
1544 * user visible, and it will not be exposed in the QOM tree.
1545 *
1546 * Returns: the internal object container
1547 */
1548Object *object_get_internal_root(void);
1549
1550/**
1551 * object_get_canonical_path_component:
1552 * @obj: the object
1553 *
1554 * Returns: The final component in the object's canonical path.  The canonical
1555 * path is the path within the composition tree starting from the root.
1556 * %NULL if the object doesn't have a parent (and thus a canonical path).
1557 */
1558const char *object_get_canonical_path_component(const Object *obj);
1559
1560/**
1561 * object_get_canonical_path:
1562 * @obj: the object
1563 *
1564 * Returns: The canonical path for a object, newly allocated.  This is
1565 * the path within the composition tree starting from the root.  Use
1566 * g_free() to free it.
1567 */
1568char *object_get_canonical_path(const Object *obj);
1569
1570/**
1571 * object_resolve_path:
1572 * @path: the path to resolve
1573 * @ambiguous: (out) (optional): location to store whether the lookup failed
1574 *   because it was ambiguous, or %NULL. Set to %false on success.
1575 *
1576 * There are two types of supported paths--absolute paths and partial paths.
1577 * 
1578 * Absolute paths are derived from the root object and can follow child<> or
1579 * link<> properties.  Since they can follow link<> properties, they can be
1580 * arbitrarily long.  Absolute paths look like absolute filenames and are
1581 * prefixed with a leading slash.
1582 * 
1583 * Partial paths look like relative filenames.  They do not begin with a
1584 * prefix.  The matching rules for partial paths are subtle but designed to make
1585 * specifying objects easy.  At each level of the composition tree, the partial
1586 * path is matched as an absolute path.  The first match is not returned.  At
1587 * least two matches are searched for.  A successful result is only returned if
1588 * only one match is found.  If more than one match is found, a flag is
1589 * returned to indicate that the match was ambiguous.
1590 *
1591 * Returns: The matched object or %NULL on path lookup failure.
1592 */
1593Object *object_resolve_path(const char *path, bool *ambiguous);
1594
1595/**
1596 * object_resolve_path_type:
1597 * @path: the path to resolve
1598 * @typename: the type to look for.
1599 * @ambiguous: (out) (optional): location to store whether the lookup failed
1600 *   because it was ambiguous, or %NULL. Set to %false on success.
1601 *
1602 * This is similar to object_resolve_path().  However, when looking for a
1603 * partial path only matches that implement the given type are considered.
1604 * This restricts the search and avoids spuriously flagging matches as
1605 * ambiguous.
1606 *
1607 * For both partial and absolute paths, the return value goes through
1608 * a dynamic cast to @typename.  This is important if either the link,
1609 * or the typename itself are of interface types.
1610 *
1611 * Returns: The matched object or NULL on path lookup failure.
1612 */
1613Object *object_resolve_path_type(const char *path, const char *typename,
1614                                 bool *ambiguous);
1615
1616/**
1617 * object_resolve_type_unambiguous:
1618 * @typename: the type to look for
1619 * @errp: pointer to error object
1620 *
1621 * Return the only object in the QOM tree of type @typename.
1622 * If no match or more than one match is found, an error is
1623 * returned.
1624 *
1625 * Returns: The matched object or NULL on path lookup failure.
1626 */
1627Object *object_resolve_type_unambiguous(const char *typename, Error **errp);
1628
1629/**
1630 * object_resolve_path_at:
1631 * @parent: the object in which to resolve the path
1632 * @path: the path to resolve
1633 *
1634 * This is like object_resolve_path(), except paths not starting with
1635 * a slash are relative to @parent.
1636 *
1637 * Returns: The resolved object or NULL on path lookup failure.
1638 */
1639Object *object_resolve_path_at(Object *parent, const char *path);
1640
1641/**
1642 * object_resolve_path_component:
1643 * @parent: the object in which to resolve the path
1644 * @part: the component to resolve.
1645 *
1646 * This is similar to object_resolve_path with an absolute path, but it
1647 * only resolves one element (@part) and takes the others from @parent.
1648 *
1649 * Returns: The resolved object or NULL on path lookup failure.
1650 */
1651Object *object_resolve_path_component(Object *parent, const char *part);
1652
1653/**
1654 * object_property_try_add_child:
1655 * @obj: the object to add a property to
1656 * @name: the name of the property
1657 * @child: the child object
1658 * @errp: pointer to error object
1659 *
1660 * Child properties form the composition tree.  All objects need to be a child
1661 * of another object.  Objects can only be a child of one object.
1662 *
1663 * There is no way for a child to determine what its parent is.  It is not
1664 * a bidirectional relationship.  This is by design.
1665 *
1666 * The value of a child property as a C string will be the child object's
1667 * canonical path. It can be retrieved using object_property_get_str().
1668 * The child object itself can be retrieved using object_property_get_link().
1669 *
1670 * Returns: The newly added property on success, or %NULL on failure.
1671 */
1672ObjectProperty *object_property_try_add_child(Object *obj, const char *name,
1673                                              Object *child, Error **errp);
1674
1675/**
1676 * object_property_add_child:
1677 * @obj: the object to add a property to
1678 * @name: the name of the property
1679 * @child: the child object
1680 *
1681 * Same as object_property_try_add_child() with @errp hardcoded to
1682 * &error_abort
1683 */
1684ObjectProperty *object_property_add_child(Object *obj, const char *name,
1685                                          Object *child);
1686
1687typedef enum {
1688    /* Unref the link pointer when the property is deleted */
1689    OBJ_PROP_LINK_STRONG = 0x1,
1690
1691    /* private */
1692    OBJ_PROP_LINK_DIRECT = 0x2,
1693    OBJ_PROP_LINK_CLASS = 0x4,
1694} ObjectPropertyLinkFlags;
1695
1696/**
1697 * object_property_allow_set_link:
1698 * @obj: the object to add a property to
1699 * @name: the name of the property
1700 * @child: the child object
1701 * @errp: pointer to error object
1702 *
1703 * The default implementation of the object_property_add_link() check()
1704 * callback function.  It allows the link property to be set and never returns
1705 * an error.
1706 */
1707void object_property_allow_set_link(const Object *obj, const char *name,
1708                                    Object *child, Error **errp);
1709
1710/**
1711 * object_property_add_link:
1712 * @obj: the object to add a property to
1713 * @name: the name of the property
1714 * @type: the qobj type of the link
1715 * @targetp: a pointer to where the link object reference is stored
1716 * @check: callback to veto setting or NULL if the property is read-only
1717 * @flags: additional options for the link
1718 *
1719 * Links establish relationships between objects.  Links are unidirectional
1720 * although two links can be combined to form a bidirectional relationship
1721 * between objects.
1722 *
1723 * Links form the graph in the object model.
1724 *
1725 * The @check() callback is invoked when
1726 * object_property_set_link() is called and can raise an error to prevent the
1727 * link being set.  If @check is NULL, the property is read-only
1728 * and cannot be set.
1729 *
1730 * Ownership of the pointer that @child points to is transferred to the
1731 * link property.  The reference count for *@child is
1732 * managed by the property from after the function returns till the
1733 * property is deleted with object_property_del().  If the
1734 * @flags %OBJ_PROP_LINK_STRONG bit is set,
1735 * the reference count is decremented when the property is deleted or
1736 * modified.
1737 *
1738 * Returns: The newly added property on success, or %NULL on failure.
1739 */
1740ObjectProperty *object_property_add_link(Object *obj, const char *name,
1741                              const char *type, Object **targetp,
1742                              void (*check)(const Object *obj, const char *name,
1743                                            Object *val, Error **errp),
1744                              ObjectPropertyLinkFlags flags);
1745
1746ObjectProperty *object_class_property_add_link(ObjectClass *oc,
1747                              const char *name,
1748                              const char *type, ptrdiff_t offset,
1749                              void (*check)(const Object *obj, const char *name,
1750                                            Object *val, Error **errp),
1751                              ObjectPropertyLinkFlags flags);
1752
1753/**
1754 * object_property_add_str:
1755 * @obj: the object to add a property to
1756 * @name: the name of the property
1757 * @get: the getter or NULL if the property is write-only.  This function must
1758 *   return a string to be freed by g_free().
1759 * @set: the setter or NULL if the property is read-only
1760 *
1761 * Add a string property using getters/setters.  This function will add a
1762 * property of type 'string'.
1763 *
1764 * Returns: The newly added property on success, or %NULL on failure.
1765 */
1766ObjectProperty *object_property_add_str(Object *obj, const char *name,
1767                             char *(*get)(Object *, Error **),
1768                             void (*set)(Object *, const char *, Error **));
1769
1770ObjectProperty *object_class_property_add_str(ObjectClass *klass,
1771                                   const char *name,
1772                                   char *(*get)(Object *, Error **),
1773                                   void (*set)(Object *, const char *,
1774                                               Error **));
1775
1776/**
1777 * object_property_add_bool:
1778 * @obj: the object to add a property to
1779 * @name: the name of the property
1780 * @get: the getter or NULL if the property is write-only.
1781 * @set: the setter or NULL if the property is read-only
1782 *
1783 * Add a bool property using getters/setters.  This function will add a
1784 * property of type 'bool'.
1785 *
1786 * Returns: The newly added property on success, or %NULL on failure.
1787 */
1788ObjectProperty *object_property_add_bool(Object *obj, const char *name,
1789                              bool (*get)(Object *, Error **),
1790                              void (*set)(Object *, bool, Error **));
1791
1792ObjectProperty *object_class_property_add_bool(ObjectClass *klass,
1793                                    const char *name,
1794                                    bool (*get)(Object *, Error **),
1795                                    void (*set)(Object *, bool, Error **));
1796
1797/**
1798 * object_property_add_enum:
1799 * @obj: the object to add a property to
1800 * @name: the name of the property
1801 * @typename: the name of the enum data type
1802 * @lookup: enum value namelookup table
1803 * @get: the getter or %NULL if the property is write-only.
1804 * @set: the setter or %NULL if the property is read-only
1805 *
1806 * Add an enum property using getters/setters.  This function will add a
1807 * property of type '@typename'.
1808 *
1809 * Returns: The newly added property on success, or %NULL on failure.
1810 */
1811ObjectProperty *object_property_add_enum(Object *obj, const char *name,
1812                              const char *typename,
1813                              const QEnumLookup *lookup,
1814                              int (*get)(Object *, Error **),
1815                              void (*set)(Object *, int, Error **));
1816
1817ObjectProperty *object_class_property_add_enum(ObjectClass *klass,
1818                                    const char *name,
1819                                    const char *typename,
1820                                    const QEnumLookup *lookup,
1821                                    int (*get)(Object *, Error **),
1822                                    void (*set)(Object *, int, Error **));
1823
1824/**
1825 * object_property_add_tm:
1826 * @obj: the object to add a property to
1827 * @name: the name of the property
1828 * @get: the getter or NULL if the property is write-only.
1829 *
1830 * Add a read-only struct tm valued property using a getter function.
1831 * This function will add a property of type 'struct tm'.
1832 *
1833 * Returns: The newly added property on success, or %NULL on failure.
1834 */
1835ObjectProperty *object_property_add_tm(Object *obj, const char *name,
1836                            void (*get)(Object *, struct tm *, Error **));
1837
1838ObjectProperty *object_class_property_add_tm(ObjectClass *klass,
1839                            const char *name,
1840                            void (*get)(Object *, struct tm *, Error **));
1841
1842typedef enum {
1843    /* Automatically add a getter to the property */
1844    OBJ_PROP_FLAG_READ = 1 << 0,
1845    /* Automatically add a setter to the property */
1846    OBJ_PROP_FLAG_WRITE = 1 << 1,
1847    /* Automatically add a getter and a setter to the property */
1848    OBJ_PROP_FLAG_READWRITE = (OBJ_PROP_FLAG_READ | OBJ_PROP_FLAG_WRITE),
1849} ObjectPropertyFlags;
1850
1851/**
1852 * object_property_add_uint8_ptr:
1853 * @obj: the object to add a property to
1854 * @name: the name of the property
1855 * @v: pointer to value
1856 * @flags: bitwise-or'd ObjectPropertyFlags
1857 *
1858 * Add an integer property in memory.  This function will add a
1859 * property of type 'uint8'.
1860 *
1861 * Returns: The newly added property on success, or %NULL on failure.
1862 */
1863ObjectProperty *object_property_add_uint8_ptr(Object *obj, const char *name,
1864                                              const uint8_t *v,
1865                                              ObjectPropertyFlags flags);
1866
1867ObjectProperty *object_class_property_add_uint8_ptr(ObjectClass *klass,
1868                                         const char *name,
1869                                         const uint8_t *v,
1870                                         ObjectPropertyFlags flags);
1871
1872/**
1873 * object_property_add_uint16_ptr:
1874 * @obj: the object to add a property to
1875 * @name: the name of the property
1876 * @v: pointer to value
1877 * @flags: bitwise-or'd ObjectPropertyFlags
1878 *
1879 * Add an integer property in memory.  This function will add a
1880 * property of type 'uint16'.
1881 *
1882 * Returns: The newly added property on success, or %NULL on failure.
1883 */
1884ObjectProperty *object_property_add_uint16_ptr(Object *obj, const char *name,
1885                                    const uint16_t *v,
1886                                    ObjectPropertyFlags flags);
1887
1888ObjectProperty *object_class_property_add_uint16_ptr(ObjectClass *klass,
1889                                          const char *name,
1890                                          const uint16_t *v,
1891                                          ObjectPropertyFlags flags);
1892
1893/**
1894 * object_property_add_uint32_ptr:
1895 * @obj: the object to add a property to
1896 * @name: the name of the property
1897 * @v: pointer to value
1898 * @flags: bitwise-or'd ObjectPropertyFlags
1899 *
1900 * Add an integer property in memory.  This function will add a
1901 * property of type 'uint32'.
1902 *
1903 * Returns: The newly added property on success, or %NULL on failure.
1904 */
1905ObjectProperty *object_property_add_uint32_ptr(Object *obj, const char *name,
1906                                    const uint32_t *v,
1907                                    ObjectPropertyFlags flags);
1908
1909ObjectProperty *object_class_property_add_uint32_ptr(ObjectClass *klass,
1910                                          const char *name,
1911                                          const uint32_t *v,
1912                                          ObjectPropertyFlags flags);
1913
1914/**
1915 * object_property_add_uint64_ptr:
1916 * @obj: the object to add a property to
1917 * @name: the name of the property
1918 * @v: pointer to value
1919 * @flags: bitwise-or'd ObjectPropertyFlags
1920 *
1921 * Add an integer property in memory.  This function will add a
1922 * property of type 'uint64'.
1923 *
1924 * Returns: The newly added property on success, or %NULL on failure.
1925 */
1926ObjectProperty *object_property_add_uint64_ptr(Object *obj, const char *name,
1927                                    const uint64_t *v,
1928                                    ObjectPropertyFlags flags);
1929
1930ObjectProperty *object_class_property_add_uint64_ptr(ObjectClass *klass,
1931                                          const char *name,
1932                                          const uint64_t *v,
1933                                          ObjectPropertyFlags flags);
1934
1935/**
1936 * object_property_add_alias:
1937 * @obj: the object to add a property to
1938 * @name: the name of the property
1939 * @target_obj: the object to forward property access to
1940 * @target_name: the name of the property on the forwarded object
1941 *
1942 * Add an alias for a property on an object.  This function will add a property
1943 * of the same type as the forwarded property.
1944 *
1945 * The caller must ensure that @target_obj stays alive as long as
1946 * this property exists.  In the case of a child object or an alias on the same
1947 * object this will be the case.  For aliases to other objects the caller is
1948 * responsible for taking a reference.
1949 *
1950 * Returns: The newly added property on success, or %NULL on failure.
1951 */
1952ObjectProperty *object_property_add_alias(Object *obj, const char *name,
1953                               Object *target_obj, const char *target_name);
1954
1955/**
1956 * object_property_add_const_link:
1957 * @obj: the object to add a property to
1958 * @name: the name of the property
1959 * @target: the object to be referred by the link
1960 *
1961 * Add an unmodifiable link for a property on an object.  This function will
1962 * add a property of type link<TYPE> where TYPE is the type of @target.
1963 *
1964 * The caller must ensure that @target stays alive as long as
1965 * this property exists.  In the case @target is a child of @obj,
1966 * this will be the case.  Otherwise, the caller is responsible for
1967 * taking a reference.
1968 *
1969 * Returns: The newly added property on success, or %NULL on failure.
1970 */
1971ObjectProperty *object_property_add_const_link(Object *obj, const char *name,
1972                                               Object *target);
1973
1974/**
1975 * object_property_set_description:
1976 * @obj: the object owning the property
1977 * @name: the name of the property
1978 * @description: the description of the property on the object
1979 *
1980 * Set an object property's description.
1981 *
1982 * Returns: %true on success, %false on failure.
1983 */
1984void object_property_set_description(Object *obj, const char *name,
1985                                     const char *description);
1986void object_class_property_set_description(ObjectClass *klass, const char *name,
1987                                           const char *description);
1988
1989/**
1990 * object_child_foreach:
1991 * @obj: the object whose children will be navigated
1992 * @fn: the iterator function to be called
1993 * @opaque: an opaque value that will be passed to the iterator
1994 *
1995 * Call @fn passing each child of @obj and @opaque to it, until @fn returns
1996 * non-zero.
1997 *
1998 * It is forbidden to add or remove children from @obj from the @fn
1999 * callback.
2000 *
2001 * Returns: The last value returned by @fn, or 0 if there is no child.
2002 */
2003int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
2004                         void *opaque);
2005
2006/**
2007 * object_child_foreach_recursive:
2008 * @obj: the object whose children will be navigated
2009 * @fn: the iterator function to be called
2010 * @opaque: an opaque value that will be passed to the iterator
2011 *
2012 * Call @fn passing each child of @obj and @opaque to it, until @fn returns
2013 * non-zero. Calls recursively, all child nodes of @obj will also be passed
2014 * all the way down to the leaf nodes of the tree. Depth first ordering.
2015 *
2016 * It is forbidden to add or remove children from @obj (or its
2017 * child nodes) from the @fn callback.
2018 *
2019 * Returns: The last value returned by @fn, or 0 if there is no child.
2020 */
2021int object_child_foreach_recursive(Object *obj,
2022                                   int (*fn)(Object *child, void *opaque),
2023                                   void *opaque);
2024
2025/**
2026 * object_property_add_new_container:
2027 * @obj: the parent object
2028 * @name: the name of the parent object's property to add
2029 *
2030 * Add a newly created container object to a parent object.
2031 *
2032 * Returns: the newly created container object.  Its reference count is 1,
2033 * and the reference is owned by the parent object.
2034 */
2035Object *object_property_add_new_container(Object *obj, const char *name);
2036
2037/**
2038 * object_property_help:
2039 * @name: the name of the property
2040 * @type: the type of the property
2041 * @defval: the default value
2042 * @description: description of the property
2043 *
2044 * Returns: a user-friendly formatted string describing the property
2045 * for help purposes.
2046 */
2047char *object_property_help(const char *name, const char *type,
2048                           QObject *defval, const char *description);
2049
2050G_DEFINE_AUTOPTR_CLEANUP_FUNC(Object, object_unref)
2051
2052#endif
2053