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 Object Object;
  24
  25typedef struct TypeInfo TypeInfo;
  26
  27typedef struct InterfaceClass InterfaceClass;
  28typedef struct InterfaceInfo InterfaceInfo;
  29
  30#define TYPE_OBJECT "object"
  31
  32/**
  33 * SECTION:object.h
  34 * @title:Base Object Type System
  35 * @short_description: interfaces for creating new types and objects
  36 *
  37 * The QEMU Object Model provides a framework for registering user creatable
  38 * types and instantiating objects from those types.  QOM provides the following
  39 * features:
  40 *
  41 *  - System for dynamically registering types
  42 *  - Support for single-inheritance of types
  43 *  - Multiple inheritance of stateless interfaces
  44 *
  45 * <example>
  46 *   <title>Creating a minimal type</title>
  47 *   <programlisting>
  48 * #include "qdev.h"
  49 *
  50 * #define TYPE_MY_DEVICE "my-device"
  51 *
  52 * // No new virtual functions: we can reuse the typedef for the
  53 * // superclass.
  54 * typedef DeviceClass MyDeviceClass;
  55 * typedef struct MyDevice
  56 * {
  57 *     DeviceState parent;
  58 *
  59 *     int reg0, reg1, reg2;
  60 * } MyDevice;
  61 *
  62 * static const TypeInfo my_device_info = {
  63 *     .name = TYPE_MY_DEVICE,
  64 *     .parent = TYPE_DEVICE,
  65 *     .instance_size = sizeof(MyDevice),
  66 * };
  67 *
  68 * static void my_device_register_types(void)
  69 * {
  70 *     type_register_static(&my_device_info);
  71 * }
  72 *
  73 * type_init(my_device_register_types)
  74 *   </programlisting>
  75 * </example>
  76 *
  77 * In the above example, we create a simple type that is described by #TypeInfo.
  78 * #TypeInfo describes information about the type including what it inherits
  79 * from, the instance and class size, and constructor/destructor hooks.
  80 *
  81 * Alternatively several static types could be registered using helper macro
  82 * DEFINE_TYPES()
  83 *
  84 * <example>
  85 *   <programlisting>
  86 * static const TypeInfo device_types_info[] = {
  87 *     {
  88 *         .name = TYPE_MY_DEVICE_A,
  89 *         .parent = TYPE_DEVICE,
  90 *         .instance_size = sizeof(MyDeviceA),
  91 *     },
  92 *     {
  93 *         .name = TYPE_MY_DEVICE_B,
  94 *         .parent = TYPE_DEVICE,
  95 *         .instance_size = sizeof(MyDeviceB),
  96 *     },
  97 * };
  98 *
  99 * DEFINE_TYPES(device_types_info)
 100 *   </programlisting>
 101 * </example>
 102 *
 103 * Every type has an #ObjectClass associated with it.  #ObjectClass derivatives
 104 * are instantiated dynamically but there is only ever one instance for any
 105 * given type.  The #ObjectClass typically holds a table of function pointers
 106 * for the virtual methods implemented by this type.
 107 *
 108 * Using object_new(), a new #Object derivative will be instantiated.  You can
 109 * cast an #Object to a subclass (or base-class) type using
 110 * object_dynamic_cast().  You typically want to define macro wrappers around
 111 * OBJECT_CHECK() and OBJECT_CLASS_CHECK() to make it easier to convert to a
 112 * specific type:
 113 *
 114 * <example>
 115 *   <title>Typecasting macros</title>
 116 *   <programlisting>
 117 *    #define MY_DEVICE_GET_CLASS(obj) \
 118 *       OBJECT_GET_CLASS(MyDeviceClass, obj, TYPE_MY_DEVICE)
 119 *    #define MY_DEVICE_CLASS(klass) \
 120 *       OBJECT_CLASS_CHECK(MyDeviceClass, klass, TYPE_MY_DEVICE)
 121 *    #define MY_DEVICE(obj) \
 122 *       OBJECT_CHECK(MyDevice, obj, TYPE_MY_DEVICE)
 123 *   </programlisting>
 124 * </example>
 125 *
 126 * # Class Initialization #
 127 *
 128 * Before an object is initialized, the class for the object must be
 129 * initialized.  There is only one class object for all instance objects
 130 * that is created lazily.
 131 *
 132 * Classes are initialized by first initializing any parent classes (if
 133 * necessary).  After the parent class object has initialized, it will be
 134 * copied into the current class object and any additional storage in the
 135 * class object is zero filled.
 136 *
 137 * The effect of this is that classes automatically inherit any virtual
 138 * function pointers that the parent class has already initialized.  All
 139 * other fields will be zero filled.
 140 *
 141 * Once all of the parent classes have been initialized, #TypeInfo::class_init
 142 * is called to let the class being instantiated provide default initialize for
 143 * its virtual functions.  Here is how the above example might be modified
 144 * to introduce an overridden virtual function:
 145 *
 146 * <example>
 147 *   <title>Overriding a virtual function</title>
 148 *   <programlisting>
 149 * #include "qdev.h"
 150 *
 151 * void my_device_class_init(ObjectClass *klass, void *class_data)
 152 * {
 153 *     DeviceClass *dc = DEVICE_CLASS(klass);
 154 *     dc->reset = my_device_reset;
 155 * }
 156 *
 157 * static const TypeInfo my_device_info = {
 158 *     .name = TYPE_MY_DEVICE,
 159 *     .parent = TYPE_DEVICE,
 160 *     .instance_size = sizeof(MyDevice),
 161 *     .class_init = my_device_class_init,
 162 * };
 163 *   </programlisting>
 164 * </example>
 165 *
 166 * Introducing new virtual methods requires a class to define its own
 167 * struct and to add a .class_size member to the #TypeInfo.  Each method
 168 * will also have a wrapper function to call it easily:
 169 *
 170 * <example>
 171 *   <title>Defining an abstract class</title>
 172 *   <programlisting>
 173 * #include "qdev.h"
 174 *
 175 * typedef struct MyDeviceClass
 176 * {
 177 *     DeviceClass parent;
 178 *
 179 *     void (*frobnicate) (MyDevice *obj);
 180 * } MyDeviceClass;
 181 *
 182 * static const TypeInfo my_device_info = {
 183 *     .name = TYPE_MY_DEVICE,
 184 *     .parent = TYPE_DEVICE,
 185 *     .instance_size = sizeof(MyDevice),
 186 *     .abstract = true, // or set a default in my_device_class_init
 187 *     .class_size = sizeof(MyDeviceClass),
 188 * };
 189 *
 190 * void my_device_frobnicate(MyDevice *obj)
 191 * {
 192 *     MyDeviceClass *klass = MY_DEVICE_GET_CLASS(obj);
 193 *
 194 *     klass->frobnicate(obj);
 195 * }
 196 *   </programlisting>
 197 * </example>
 198 *
 199 * # Interfaces #
 200 *
 201 * Interfaces allow a limited form of multiple inheritance.  Instances are
 202 * similar to normal types except for the fact that are only defined by
 203 * their classes and never carry any state.  As a consequence, a pointer to
 204 * an interface instance should always be of incomplete type in order to be
 205 * sure it cannot be dereferenced.  That is, you should define the
 206 * 'typedef struct SomethingIf SomethingIf' so that you can pass around
 207 * 'SomethingIf *si' arguments, but not define a 'struct SomethingIf { ... }'.
 208 * The only things you can validly do with a 'SomethingIf *' are to pass it as
 209 * an argument to a method on its corresponding SomethingIfClass, or to
 210 * dynamically cast it to an object that implements the interface.
 211 *
 212 * # Methods #
 213 *
 214 * A <emphasis>method</emphasis> is a function within the namespace scope of
 215 * a class. It usually operates on the object instance by passing it as a
 216 * strongly-typed first argument.
 217 * If it does not operate on an object instance, it is dubbed
 218 * <emphasis>class method</emphasis>.
 219 *
 220 * Methods cannot be overloaded. That is, the #ObjectClass and method name
 221 * uniquely identity the function to be called; the signature does not vary
 222 * except for trailing varargs.
 223 *
 224 * Methods are always <emphasis>virtual</emphasis>. Overriding a method in
 225 * #TypeInfo.class_init of a subclass leads to any user of the class obtained
 226 * via OBJECT_GET_CLASS() accessing the overridden function.
 227 * The original function is not automatically invoked. It is the responsibility
 228 * of the overriding class to determine whether and when to invoke the method
 229 * being overridden.
 230 *
 231 * To invoke the method being overridden, the preferred solution is to store
 232 * the original value in the overriding class before overriding the method.
 233 * This corresponds to |[ {super,base}.method(...) ]| in Java and C#
 234 * respectively; this frees the overriding class from hardcoding its parent
 235 * class, which someone might choose to change at some point.
 236 *
 237 * <example>
 238 *   <title>Overriding a virtual method</title>
 239 *   <programlisting>
 240 * typedef struct MyState MyState;
 241 *
 242 * typedef void (*MyDoSomething)(MyState *obj);
 243 *
 244 * typedef struct MyClass {
 245 *     ObjectClass parent_class;
 246 *
 247 *     MyDoSomething do_something;
 248 * } MyClass;
 249 *
 250 * static void my_do_something(MyState *obj)
 251 * {
 252 *     // do something
 253 * }
 254 *
 255 * static void my_class_init(ObjectClass *oc, void *data)
 256 * {
 257 *     MyClass *mc = MY_CLASS(oc);
 258 *
 259 *     mc->do_something = my_do_something;
 260 * }
 261 *
 262 * static const TypeInfo my_type_info = {
 263 *     .name = TYPE_MY,
 264 *     .parent = TYPE_OBJECT,
 265 *     .instance_size = sizeof(MyState),
 266 *     .class_size = sizeof(MyClass),
 267 *     .class_init = my_class_init,
 268 * };
 269 *
 270 * typedef struct DerivedClass {
 271 *     MyClass parent_class;
 272 *
 273 *     MyDoSomething parent_do_something;
 274 * } DerivedClass;
 275 *
 276 * static void derived_do_something(MyState *obj)
 277 * {
 278 *     DerivedClass *dc = DERIVED_GET_CLASS(obj);
 279 *
 280 *     // do something here
 281 *     dc->parent_do_something(obj);
 282 *     // do something else here
 283 * }
 284 *
 285 * static void derived_class_init(ObjectClass *oc, void *data)
 286 * {
 287 *     MyClass *mc = MY_CLASS(oc);
 288 *     DerivedClass *dc = DERIVED_CLASS(oc);
 289 *
 290 *     dc->parent_do_something = mc->do_something;
 291 *     mc->do_something = derived_do_something;
 292 * }
 293 *
 294 * static const TypeInfo derived_type_info = {
 295 *     .name = TYPE_DERIVED,
 296 *     .parent = TYPE_MY,
 297 *     .class_size = sizeof(DerivedClass),
 298 *     .class_init = derived_class_init,
 299 * };
 300 *   </programlisting>
 301 * </example>
 302 *
 303 * Alternatively, object_class_by_name() can be used to obtain the class and
 304 * its non-overridden methods for a specific type. This would correspond to
 305 * |[ MyClass::method(...) ]| in C++.
 306 *
 307 * The first example of such a QOM method was #CPUClass.reset,
 308 * another example is #DeviceClass.realize.
 309 */
 310
 311
 312typedef struct ObjectProperty ObjectProperty;
 313
 314/**
 315 * ObjectPropertyAccessor:
 316 * @obj: the object that owns the property
 317 * @v: the visitor that contains the property data
 318 * @name: the name of the property
 319 * @opaque: the object property opaque
 320 * @errp: a pointer to an Error that is filled if getting/setting fails.
 321 *
 322 * Called when trying to get/set a property.
 323 */
 324typedef void (ObjectPropertyAccessor)(Object *obj,
 325                                      Visitor *v,
 326                                      const char *name,
 327                                      void *opaque,
 328                                      Error **errp);
 329
 330/**
 331 * ObjectPropertyResolve:
 332 * @obj: the object that owns the property
 333 * @opaque: the opaque registered with the property
 334 * @part: the name of the property
 335 *
 336 * Resolves the #Object corresponding to property @part.
 337 *
 338 * The returned object can also be used as a starting point
 339 * to resolve a relative path starting with "@part".
 340 *
 341 * Returns: If @path is the path that led to @obj, the function
 342 * returns the #Object corresponding to "@path/@part".
 343 * If "@path/@part" is not a valid object path, it returns #NULL.
 344 */
 345typedef Object *(ObjectPropertyResolve)(Object *obj,
 346                                        void *opaque,
 347                                        const char *part);
 348
 349/**
 350 * ObjectPropertyRelease:
 351 * @obj: the object that owns the property
 352 * @name: the name of the property
 353 * @opaque: the opaque registered with the property
 354 *
 355 * Called when a property is removed from a object.
 356 */
 357typedef void (ObjectPropertyRelease)(Object *obj,
 358                                     const char *name,
 359                                     void *opaque);
 360
 361/**
 362 * ObjectPropertyInit:
 363 * @obj: the object that owns the property
 364 * @prop: the property to set
 365 *
 366 * Called when a property is initialized.
 367 */
 368typedef void (ObjectPropertyInit)(Object *obj, ObjectProperty *prop);
 369
 370struct ObjectProperty
 371{
 372    gchar *name;
 373    gchar *type;
 374    gchar *description;
 375    ObjectPropertyAccessor *get;
 376    ObjectPropertyAccessor *set;
 377    ObjectPropertyResolve *resolve;
 378    ObjectPropertyRelease *release;
 379    ObjectPropertyInit *init;
 380    void *opaque;
 381    QObject *defval;
 382};
 383
 384/**
 385 * ObjectUnparent:
 386 * @obj: the object that is being removed from the composition tree
 387 *
 388 * Called when an object is being removed from the QOM composition tree.
 389 * The function should remove any backlinks from children objects to @obj.
 390 */
 391typedef void (ObjectUnparent)(Object *obj);
 392
 393/**
 394 * ObjectFree:
 395 * @obj: the object being freed
 396 *
 397 * Called when an object's last reference is removed.
 398 */
 399typedef void (ObjectFree)(void *obj);
 400
 401#define OBJECT_CLASS_CAST_CACHE 4
 402
 403/**
 404 * ObjectClass:
 405 *
 406 * The base for all classes.  The only thing that #ObjectClass contains is an
 407 * integer type handle.
 408 */
 409struct ObjectClass
 410{
 411    /*< private >*/
 412    Type type;
 413    GSList *interfaces;
 414
 415    const char *object_cast_cache[OBJECT_CLASS_CAST_CACHE];
 416    const char *class_cast_cache[OBJECT_CLASS_CAST_CACHE];
 417
 418    ObjectUnparent *unparent;
 419
 420    GHashTable *properties;
 421};
 422
 423/**
 424 * Object:
 425 *
 426 * The base for all objects.  The first member of this object is a pointer to
 427 * a #ObjectClass.  Since C guarantees that the first member of a structure
 428 * always begins at byte 0 of that structure, as long as any sub-object places
 429 * its parent as the first member, we can cast directly to a #Object.
 430 *
 431 * As a result, #Object contains a reference to the objects type as its
 432 * first member.  This allows identification of the real type of the object at
 433 * run time.
 434 */
 435struct Object
 436{
 437    /*< private >*/
 438    ObjectClass *class;
 439    ObjectFree *free;
 440    GHashTable *properties;
 441    uint32_t ref;
 442    Object *parent;
 443};
 444
 445/**
 446 * TypeInfo:
 447 * @name: The name of the type.
 448 * @parent: The name of the parent type.
 449 * @instance_size: The size of the object (derivative of #Object).  If
 450 *   @instance_size is 0, then the size of the object will be the size of the
 451 *   parent object.
 452 * @instance_init: This function is called to initialize an object.  The parent
 453 *   class will have already been initialized so the type is only responsible
 454 *   for initializing its own members.
 455 * @instance_post_init: This function is called to finish initialization of
 456 *   an object, after all @instance_init functions were called.
 457 * @instance_finalize: This function is called during object destruction.  This
 458 *   is called before the parent @instance_finalize function has been called.
 459 *   An object should only free the members that are unique to its type in this
 460 *   function.
 461 * @abstract: If this field is true, then the class is considered abstract and
 462 *   cannot be directly instantiated.
 463 * @class_size: The size of the class object (derivative of #ObjectClass)
 464 *   for this object.  If @class_size is 0, then the size of the class will be
 465 *   assumed to be the size of the parent class.  This allows a type to avoid
 466 *   implementing an explicit class type if they are not adding additional
 467 *   virtual functions.
 468 * @class_init: This function is called after all parent class initialization
 469 *   has occurred to allow a class to set its default virtual method pointers.
 470 *   This is also the function to use to override virtual methods from a parent
 471 *   class.
 472 * @class_base_init: This function is called for all base classes after all
 473 *   parent class initialization has occurred, but before the class itself
 474 *   is initialized.  This is the function to use to undo the effects of
 475 *   memcpy from the parent class to the descendants.
 476 * @class_data: Data to pass to the @class_init,
 477 *   @class_base_init. This can be useful when building dynamic
 478 *   classes.
 479 * @interfaces: The list of interfaces associated with this type.  This
 480 *   should point to a static array that's terminated with a zero filled
 481 *   element.
 482 */
 483struct TypeInfo
 484{
 485    const char *name;
 486    const char *parent;
 487
 488    size_t instance_size;
 489    void (*instance_init)(Object *obj);
 490    void (*instance_post_init)(Object *obj);
 491    void (*instance_finalize)(Object *obj);
 492
 493    bool abstract;
 494    size_t class_size;
 495
 496    void (*class_init)(ObjectClass *klass, void *data);
 497    void (*class_base_init)(ObjectClass *klass, void *data);
 498    void *class_data;
 499
 500    InterfaceInfo *interfaces;
 501};
 502
 503/**
 504 * OBJECT:
 505 * @obj: A derivative of #Object
 506 *
 507 * Converts an object to a #Object.  Since all objects are #Objects,
 508 * this function will always succeed.
 509 */
 510#define OBJECT(obj) \
 511    ((Object *)(obj))
 512
 513/**
 514 * OBJECT_CLASS:
 515 * @class: A derivative of #ObjectClass.
 516 *
 517 * Converts a class to an #ObjectClass.  Since all objects are #Objects,
 518 * this function will always succeed.
 519 */
 520#define OBJECT_CLASS(class) \
 521    ((ObjectClass *)(class))
 522
 523/**
 524 * OBJECT_CHECK:
 525 * @type: The C type to use for the return value.
 526 * @obj: A derivative of @type to cast.
 527 * @name: The QOM typename of @type
 528 *
 529 * A type safe version of @object_dynamic_cast_assert.  Typically each class
 530 * will define a macro based on this type to perform type safe dynamic_casts to
 531 * this object type.
 532 *
 533 * If an invalid object is passed to this function, a run time assert will be
 534 * generated.
 535 */
 536#define OBJECT_CHECK(type, obj, name) \
 537    ((type *)object_dynamic_cast_assert(OBJECT(obj), (name), \
 538                                        __FILE__, __LINE__, __func__))
 539
 540/**
 541 * OBJECT_CLASS_CHECK:
 542 * @class_type: The C type to use for the return value.
 543 * @class: A derivative class of @class_type to cast.
 544 * @name: the QOM typename of @class_type.
 545 *
 546 * A type safe version of @object_class_dynamic_cast_assert.  This macro is
 547 * typically wrapped by each type to perform type safe casts of a class to a
 548 * specific class type.
 549 */
 550#define OBJECT_CLASS_CHECK(class_type, class, name) \
 551    ((class_type *)object_class_dynamic_cast_assert(OBJECT_CLASS(class), (name), \
 552                                               __FILE__, __LINE__, __func__))
 553
 554/**
 555 * OBJECT_GET_CLASS:
 556 * @class: The C type to use for the return value.
 557 * @obj: The object to obtain the class for.
 558 * @name: The QOM typename of @obj.
 559 *
 560 * This function will return a specific class for a given object.  Its generally
 561 * used by each type to provide a type safe macro to get a specific class type
 562 * from an object.
 563 */
 564#define OBJECT_GET_CLASS(class, obj, name) \
 565    OBJECT_CLASS_CHECK(class, object_get_class(OBJECT(obj)), name)
 566
 567/**
 568 * InterfaceInfo:
 569 * @type: The name of the interface.
 570 *
 571 * The information associated with an interface.
 572 */
 573struct InterfaceInfo {
 574    const char *type;
 575};
 576
 577/**
 578 * InterfaceClass:
 579 * @parent_class: the base class
 580 *
 581 * The class for all interfaces.  Subclasses of this class should only add
 582 * virtual methods.
 583 */
 584struct InterfaceClass
 585{
 586    ObjectClass parent_class;
 587    /*< private >*/
 588    ObjectClass *concrete_class;
 589    Type interface_type;
 590};
 591
 592#define TYPE_INTERFACE "interface"
 593
 594/**
 595 * INTERFACE_CLASS:
 596 * @klass: class to cast from
 597 * Returns: An #InterfaceClass or raise an error if cast is invalid
 598 */
 599#define INTERFACE_CLASS(klass) \
 600    OBJECT_CLASS_CHECK(InterfaceClass, klass, TYPE_INTERFACE)
 601
 602/**
 603 * INTERFACE_CHECK:
 604 * @interface: the type to return
 605 * @obj: the object to convert to an interface
 606 * @name: the interface type name
 607 *
 608 * Returns: @obj casted to @interface if cast is valid, otherwise raise error.
 609 */
 610#define INTERFACE_CHECK(interface, obj, name) \
 611    ((interface *)object_dynamic_cast_assert(OBJECT((obj)), (name), \
 612                                             __FILE__, __LINE__, __func__))
 613
 614/**
 615 * object_new_with_class:
 616 * @klass: The class to instantiate.
 617 *
 618 * This function will initialize a new object using heap allocated memory.
 619 * The returned object has a reference count of 1, and will be freed when
 620 * the last reference is dropped.
 621 *
 622 * Returns: The newly allocated and instantiated object.
 623 */
 624Object *object_new_with_class(ObjectClass *klass);
 625
 626/**
 627 * object_new:
 628 * @typename: The name of the type of the object to instantiate.
 629 *
 630 * This function will initialize a new object using heap allocated memory.
 631 * The returned object has a reference count of 1, and will be freed when
 632 * the last reference is dropped.
 633 *
 634 * Returns: The newly allocated and instantiated object.
 635 */
 636Object *object_new(const char *typename);
 637
 638/**
 639 * object_new_with_props:
 640 * @typename:  The name of the type of the object to instantiate.
 641 * @parent: the parent object
 642 * @id: The unique ID of the object
 643 * @errp: pointer to error object
 644 * @...: list of property names and values
 645 *
 646 * This function will initialize a new object using heap allocated memory.
 647 * The returned object has a reference count of 1, and will be freed when
 648 * the last reference is dropped.
 649 *
 650 * The @id parameter will be used when registering the object as a
 651 * child of @parent in the composition tree.
 652 *
 653 * The variadic parameters are a list of pairs of (propname, propvalue)
 654 * strings. The propname of %NULL indicates the end of the property
 655 * list. If the object implements the user creatable interface, the
 656 * object will be marked complete once all the properties have been
 657 * processed.
 658 *
 659 * <example>
 660 *   <title>Creating an object with properties</title>
 661 *   <programlisting>
 662 *   Error *err = NULL;
 663 *   Object *obj;
 664 *
 665 *   obj = object_new_with_props(TYPE_MEMORY_BACKEND_FILE,
 666 *                               object_get_objects_root(),
 667 *                               "hostmem0",
 668 *                               &err,
 669 *                               "share", "yes",
 670 *                               "mem-path", "/dev/shm/somefile",
 671 *                               "prealloc", "yes",
 672 *                               "size", "1048576",
 673 *                               NULL);
 674 *
 675 *   if (!obj) {
 676 *     g_printerr("Cannot create memory backend: %s\n",
 677 *                error_get_pretty(err));
 678 *   }
 679 *   </programlisting>
 680 * </example>
 681 *
 682 * The returned object will have one stable reference maintained
 683 * for as long as it is present in the object hierarchy.
 684 *
 685 * Returns: The newly allocated, instantiated & initialized object.
 686 */
 687Object *object_new_with_props(const char *typename,
 688                              Object *parent,
 689                              const char *id,
 690                              Error **errp,
 691                              ...) QEMU_SENTINEL;
 692
 693/**
 694 * object_new_with_propv:
 695 * @typename:  The name of the type of the object to instantiate.
 696 * @parent: the parent object
 697 * @id: The unique ID of the object
 698 * @errp: pointer to error object
 699 * @vargs: list of property names and values
 700 *
 701 * See object_new_with_props() for documentation.
 702 */
 703Object *object_new_with_propv(const char *typename,
 704                              Object *parent,
 705                              const char *id,
 706                              Error **errp,
 707                              va_list vargs);
 708
 709void object_apply_global_props(Object *obj, const GPtrArray *props,
 710                               Error **errp);
 711void object_set_machine_compat_props(GPtrArray *compat_props);
 712void object_set_accelerator_compat_props(GPtrArray *compat_props);
 713void object_register_sugar_prop(const char *driver, const char *prop, const char *value);
 714void object_apply_compat_props(Object *obj);
 715
 716/**
 717 * object_set_props:
 718 * @obj: the object instance to set properties on
 719 * @errp: pointer to error object
 720 * @...: list of property names and values
 721 *
 722 * This function will set a list of properties on an existing object
 723 * instance.
 724 *
 725 * The variadic parameters are a list of pairs of (propname, propvalue)
 726 * strings. The propname of %NULL indicates the end of the property
 727 * list.
 728 *
 729 * <example>
 730 *   <title>Update an object's properties</title>
 731 *   <programlisting>
 732 *   Error *err = NULL;
 733 *   Object *obj = ...get / create object...;
 734 *
 735 *   obj = object_set_props(obj,
 736 *                          &err,
 737 *                          "share", "yes",
 738 *                          "mem-path", "/dev/shm/somefile",
 739 *                          "prealloc", "yes",
 740 *                          "size", "1048576",
 741 *                          NULL);
 742 *
 743 *   if (!obj) {
 744 *     g_printerr("Cannot set properties: %s\n",
 745 *                error_get_pretty(err));
 746 *   }
 747 *   </programlisting>
 748 * </example>
 749 *
 750 * The returned object will have one stable reference maintained
 751 * for as long as it is present in the object hierarchy.
 752 *
 753 * Returns: -1 on error, 0 on success
 754 */
 755int object_set_props(Object *obj,
 756                     Error **errp,
 757                     ...) QEMU_SENTINEL;
 758
 759/**
 760 * object_set_propv:
 761 * @obj: the object instance to set properties on
 762 * @errp: pointer to error object
 763 * @vargs: list of property names and values
 764 *
 765 * See object_set_props() for documentation.
 766 *
 767 * Returns: -1 on error, 0 on success
 768 */
 769int object_set_propv(Object *obj,
 770                     Error **errp,
 771                     va_list vargs);
 772
 773/**
 774 * object_initialize:
 775 * @obj: A pointer to the memory to be used for the object.
 776 * @size: The maximum size available at @obj for the object.
 777 * @typename: The name of the type of the object to instantiate.
 778 *
 779 * This function will initialize an object.  The memory for the object should
 780 * have already been allocated.  The returned object has a reference count of 1,
 781 * and will be finalized when the last reference is dropped.
 782 */
 783void object_initialize(void *obj, size_t size, const char *typename);
 784
 785/**
 786 * object_initialize_child:
 787 * @parentobj: The parent object to add a property to
 788 * @propname: The name of the property
 789 * @childobj: A pointer to the memory to be used for the object.
 790 * @size: The maximum size available at @childobj for the object.
 791 * @type: The name of the type of the object to instantiate.
 792 * @errp: If an error occurs, a pointer to an area to store the error
 793 * @...: list of property names and values
 794 *
 795 * This function will initialize an object. The memory for the object should
 796 * have already been allocated. The object will then be added as child property
 797 * to a parent with object_property_add_child() function. The returned object
 798 * has a reference count of 1 (for the "child<...>" property from the parent),
 799 * so the object will be finalized automatically when the parent gets removed.
 800 *
 801 * The variadic parameters are a list of pairs of (propname, propvalue)
 802 * strings. The propname of %NULL indicates the end of the property list.
 803 * If the object implements the user creatable interface, the object will
 804 * be marked complete once all the properties have been processed.
 805 */
 806void object_initialize_child(Object *parentobj, const char *propname,
 807                             void *childobj, size_t size, const char *type,
 808                             Error **errp, ...) QEMU_SENTINEL;
 809
 810/**
 811 * object_initialize_childv:
 812 * @parentobj: The parent object to add a property to
 813 * @propname: The name of the property
 814 * @childobj: A pointer to the memory to be used for the object.
 815 * @size: The maximum size available at @childobj for the object.
 816 * @type: The name of the type of the object to instantiate.
 817 * @errp: If an error occurs, a pointer to an area to store the error
 818 * @vargs: list of property names and values
 819 *
 820 * See object_initialize_child() for documentation.
 821 */
 822void object_initialize_childv(Object *parentobj, const char *propname,
 823                              void *childobj, size_t size, const char *type,
 824                              Error **errp, va_list vargs);
 825
 826/**
 827 * object_dynamic_cast:
 828 * @obj: The object to cast.
 829 * @typename: The @typename to cast to.
 830 *
 831 * This function will determine if @obj is-a @typename.  @obj can refer to an
 832 * object or an interface associated with an object.
 833 *
 834 * Returns: This function returns @obj on success or #NULL on failure.
 835 */
 836Object *object_dynamic_cast(Object *obj, const char *typename);
 837
 838/**
 839 * object_dynamic_cast_assert:
 840 *
 841 * See object_dynamic_cast() for a description of the parameters of this
 842 * function.  The only difference in behavior is that this function asserts
 843 * instead of returning #NULL on failure if QOM cast debugging is enabled.
 844 * This function is not meant to be called directly, but only through
 845 * the wrapper macro OBJECT_CHECK.
 846 */
 847Object *object_dynamic_cast_assert(Object *obj, const char *typename,
 848                                   const char *file, int line, const char *func);
 849
 850/**
 851 * object_get_class:
 852 * @obj: A derivative of #Object
 853 *
 854 * Returns: The #ObjectClass of the type associated with @obj.
 855 */
 856ObjectClass *object_get_class(Object *obj);
 857
 858/**
 859 * object_get_typename:
 860 * @obj: A derivative of #Object.
 861 *
 862 * Returns: The QOM typename of @obj.
 863 */
 864const char *object_get_typename(const Object *obj);
 865
 866/**
 867 * type_register_static:
 868 * @info: The #TypeInfo of the new type.
 869 *
 870 * @info and all of the strings it points to should exist for the life time
 871 * that the type is registered.
 872 *
 873 * Returns: the new #Type.
 874 */
 875Type type_register_static(const TypeInfo *info);
 876
 877/**
 878 * type_register:
 879 * @info: The #TypeInfo of the new type
 880 *
 881 * Unlike type_register_static(), this call does not require @info or its
 882 * string members to continue to exist after the call returns.
 883 *
 884 * Returns: the new #Type.
 885 */
 886Type type_register(const TypeInfo *info);
 887
 888/**
 889 * type_register_static_array:
 890 * @infos: The array of the new type #TypeInfo structures.
 891 * @nr_infos: number of entries in @infos
 892 *
 893 * @infos and all of the strings it points to should exist for the life time
 894 * that the type is registered.
 895 */
 896void type_register_static_array(const TypeInfo *infos, int nr_infos);
 897
 898/**
 899 * DEFINE_TYPES:
 900 * @type_array: The array containing #TypeInfo structures to register
 901 *
 902 * @type_array should be static constant that exists for the life time
 903 * that the type is registered.
 904 */
 905#define DEFINE_TYPES(type_array)                                            \
 906static void do_qemu_init_ ## type_array(void)                               \
 907{                                                                           \
 908    type_register_static_array(type_array, ARRAY_SIZE(type_array));         \
 909}                                                                           \
 910type_init(do_qemu_init_ ## type_array)
 911
 912/**
 913 * object_class_dynamic_cast_assert:
 914 * @klass: The #ObjectClass to attempt to cast.
 915 * @typename: The QOM typename of the class to cast to.
 916 *
 917 * See object_class_dynamic_cast() for a description of the parameters
 918 * of this function.  The only difference in behavior is that this function
 919 * asserts instead of returning #NULL on failure if QOM cast debugging is
 920 * enabled.  This function is not meant to be called directly, but only through
 921 * the wrapper macros OBJECT_CLASS_CHECK and INTERFACE_CHECK.
 922 */
 923ObjectClass *object_class_dynamic_cast_assert(ObjectClass *klass,
 924                                              const char *typename,
 925                                              const char *file, int line,
 926                                              const char *func);
 927
 928/**
 929 * object_class_dynamic_cast:
 930 * @klass: The #ObjectClass to attempt to cast.
 931 * @typename: The QOM typename of the class to cast to.
 932 *
 933 * Returns: If @typename is a class, this function returns @klass if
 934 * @typename is a subtype of @klass, else returns #NULL.
 935 *
 936 * If @typename is an interface, this function returns the interface
 937 * definition for @klass if @klass implements it unambiguously; #NULL
 938 * is returned if @klass does not implement the interface or if multiple
 939 * classes or interfaces on the hierarchy leading to @klass implement
 940 * it.  (FIXME: perhaps this can be detected at type definition time?)
 941 */
 942ObjectClass *object_class_dynamic_cast(ObjectClass *klass,
 943                                       const char *typename);
 944
 945/**
 946 * object_class_get_parent:
 947 * @klass: The class to obtain the parent for.
 948 *
 949 * Returns: The parent for @klass or %NULL if none.
 950 */
 951ObjectClass *object_class_get_parent(ObjectClass *klass);
 952
 953/**
 954 * object_class_get_name:
 955 * @klass: The class to obtain the QOM typename for.
 956 *
 957 * Returns: The QOM typename for @klass.
 958 */
 959const char *object_class_get_name(ObjectClass *klass);
 960
 961/**
 962 * object_class_is_abstract:
 963 * @klass: The class to obtain the abstractness for.
 964 *
 965 * Returns: %true if @klass is abstract, %false otherwise.
 966 */
 967bool object_class_is_abstract(ObjectClass *klass);
 968
 969/**
 970 * object_class_by_name:
 971 * @typename: The QOM typename to obtain the class for.
 972 *
 973 * Returns: The class for @typename or %NULL if not found.
 974 */
 975ObjectClass *object_class_by_name(const char *typename);
 976
 977void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
 978                          const char *implements_type, bool include_abstract,
 979                          void *opaque);
 980
 981/**
 982 * object_class_get_list:
 983 * @implements_type: The type to filter for, including its derivatives.
 984 * @include_abstract: Whether to include abstract classes.
 985 *
 986 * Returns: A singly-linked list of the classes in reverse hashtable order.
 987 */
 988GSList *object_class_get_list(const char *implements_type,
 989                              bool include_abstract);
 990
 991/**
 992 * object_class_get_list_sorted:
 993 * @implements_type: The type to filter for, including its derivatives.
 994 * @include_abstract: Whether to include abstract classes.
 995 *
 996 * Returns: A singly-linked list of the classes in alphabetical
 997 * case-insensitive order.
 998 */
 999GSList *object_class_get_list_sorted(const char *implements_type,
1000                              bool include_abstract);
1001
1002/**
1003 * object_ref:
1004 * @obj: the object
1005 *
1006 * Increase the reference count of a object.  A object cannot be freed as long
1007 * as its reference count is greater than zero.
1008 * Returns: @obj
1009 */
1010Object *object_ref(Object *obj);
1011
1012/**
1013 * object_unref:
1014 * @obj: the object
1015 *
1016 * Decrease the reference count of a object.  A object cannot be freed as long
1017 * as its reference count is greater than zero.
1018 */
1019void object_unref(Object *obj);
1020
1021/**
1022 * object_property_add:
1023 * @obj: the object to add a property to
1024 * @name: the name of the property.  This can contain any character except for
1025 *  a forward slash.  In general, you should use hyphens '-' instead of
1026 *  underscores '_' when naming properties.
1027 * @type: the type name of the property.  This namespace is pretty loosely
1028 *   defined.  Sub namespaces are constructed by using a prefix and then
1029 *   to angle brackets.  For instance, the type 'virtio-net-pci' in the
1030 *   'link' namespace would be 'link<virtio-net-pci>'.
1031 * @get: The getter to be called to read a property.  If this is NULL, then
1032 *   the property cannot be read.
1033 * @set: the setter to be called to write a property.  If this is NULL,
1034 *   then the property cannot be written.
1035 * @release: called when the property is removed from the object.  This is
1036 *   meant to allow a property to free its opaque upon object
1037 *   destruction.  This may be NULL.
1038 * @opaque: an opaque pointer to pass to the callbacks for the property
1039 * @errp: returns an error if this function fails
1040 *
1041 * Returns: The #ObjectProperty; this can be used to set the @resolve
1042 * callback for child and link properties.
1043 */
1044ObjectProperty *object_property_add(Object *obj, const char *name,
1045                                    const char *type,
1046                                    ObjectPropertyAccessor *get,
1047                                    ObjectPropertyAccessor *set,
1048                                    ObjectPropertyRelease *release,
1049                                    void *opaque, Error **errp);
1050
1051void object_property_del(Object *obj, const char *name, Error **errp);
1052
1053ObjectProperty *object_class_property_add(ObjectClass *klass, const char *name,
1054                                          const char *type,
1055                                          ObjectPropertyAccessor *get,
1056                                          ObjectPropertyAccessor *set,
1057                                          ObjectPropertyRelease *release,
1058                                          void *opaque, Error **errp);
1059
1060/**
1061 * object_property_set_default_bool:
1062 * @prop: the property to set
1063 * @value: the value to be written to the property
1064 *
1065 * Set the property default value.
1066 */
1067void object_property_set_default_bool(ObjectProperty *prop, bool value);
1068
1069/**
1070 * object_property_set_default_str:
1071 * @prop: the property to set
1072 * @value: the value to be written to the property
1073 *
1074 * Set the property default value.
1075 */
1076void object_property_set_default_str(ObjectProperty *prop, const char *value);
1077
1078/**
1079 * object_property_set_default_int:
1080 * @prop: the property to set
1081 * @value: the value to be written to the property
1082 *
1083 * Set the property default value.
1084 */
1085void object_property_set_default_int(ObjectProperty *prop, int64_t value);
1086
1087/**
1088 * object_property_set_default_uint:
1089 * @prop: the property to set
1090 * @value: the value to be written to the property
1091 *
1092 * Set the property default value.
1093 */
1094void object_property_set_default_uint(ObjectProperty *prop, uint64_t value);
1095
1096/**
1097 * object_property_find:
1098 * @obj: the object
1099 * @name: the name of the property
1100 * @errp: returns an error if this function fails
1101 *
1102 * Look up a property for an object and return its #ObjectProperty if found.
1103 */
1104ObjectProperty *object_property_find(Object *obj, const char *name,
1105                                     Error **errp);
1106ObjectProperty *object_class_property_find(ObjectClass *klass, const char *name,
1107                                           Error **errp);
1108
1109typedef struct ObjectPropertyIterator {
1110    ObjectClass *nextclass;
1111    GHashTableIter iter;
1112} ObjectPropertyIterator;
1113
1114/**
1115 * object_property_iter_init:
1116 * @obj: the object
1117 *
1118 * Initializes an iterator for traversing all properties
1119 * registered against an object instance, its class and all parent classes.
1120 *
1121 * It is forbidden to modify the property list while iterating,
1122 * whether removing or adding properties.
1123 *
1124 * Typical usage pattern would be
1125 *
1126 * <example>
1127 *   <title>Using object property iterators</title>
1128 *   <programlisting>
1129 *   ObjectProperty *prop;
1130 *   ObjectPropertyIterator iter;
1131 *
1132 *   object_property_iter_init(&iter, obj);
1133 *   while ((prop = object_property_iter_next(&iter))) {
1134 *     ... do something with prop ...
1135 *   }
1136 *   </programlisting>
1137 * </example>
1138 */
1139void object_property_iter_init(ObjectPropertyIterator *iter,
1140                               Object *obj);
1141
1142/**
1143 * object_class_property_iter_init:
1144 * @klass: the class
1145 *
1146 * Initializes an iterator for traversing all properties
1147 * registered against an object class and all parent classes.
1148 *
1149 * It is forbidden to modify the property list while iterating,
1150 * whether removing or adding properties.
1151 *
1152 * This can be used on abstract classes as it does not create a temporary
1153 * instance.
1154 */
1155void object_class_property_iter_init(ObjectPropertyIterator *iter,
1156                                     ObjectClass *klass);
1157
1158/**
1159 * object_property_iter_next:
1160 * @iter: the iterator instance
1161 *
1162 * Return the next available property. If no further properties
1163 * are available, a %NULL value will be returned and the @iter
1164 * pointer should not be used again after this point without
1165 * re-initializing it.
1166 *
1167 * Returns: the next property, or %NULL when all properties
1168 * have been traversed.
1169 */
1170ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter);
1171
1172void object_unparent(Object *obj);
1173
1174/**
1175 * object_property_get:
1176 * @obj: the object
1177 * @v: the visitor that will receive the property value.  This should be an
1178 *   Output visitor and the data will be written with @name as the name.
1179 * @name: the name of the property
1180 * @errp: returns an error if this function fails
1181 *
1182 * Reads a property from a object.
1183 */
1184void object_property_get(Object *obj, Visitor *v, const char *name,
1185                         Error **errp);
1186
1187/**
1188 * object_property_set_str:
1189 * @value: the value to be written to the property
1190 * @name: the name of the property
1191 * @errp: returns an error if this function fails
1192 *
1193 * Writes a string value to a property.
1194 */
1195void object_property_set_str(Object *obj, const char *value,
1196                             const char *name, Error **errp);
1197
1198/**
1199 * object_property_get_str:
1200 * @obj: the object
1201 * @name: the name of the property
1202 * @errp: returns an error if this function fails
1203 *
1204 * Returns: the value of the property, converted to a C string, or NULL if
1205 * an error occurs (including when the property value is not a string).
1206 * The caller should free the string.
1207 */
1208char *object_property_get_str(Object *obj, const char *name,
1209                              Error **errp);
1210
1211/**
1212 * object_property_set_link:
1213 * @value: the value to be written to the property
1214 * @name: the name of the property
1215 * @errp: returns an error if this function fails
1216 *
1217 * Writes an object's canonical path to a property.
1218 *
1219 * If the link property was created with
1220 * <code>OBJ_PROP_LINK_STRONG</code> bit, the old target object is
1221 * unreferenced, and a reference is added to the new target object.
1222 *
1223 */
1224void object_property_set_link(Object *obj, Object *value,
1225                              const char *name, Error **errp);
1226
1227/**
1228 * object_property_get_link:
1229 * @obj: the object
1230 * @name: the name of the property
1231 * @errp: returns an error if this function fails
1232 *
1233 * Returns: the value of the property, resolved from a path to an Object,
1234 * or NULL if an error occurs (including when the property value is not a
1235 * string or not a valid object path).
1236 */
1237Object *object_property_get_link(Object *obj, const char *name,
1238                                 Error **errp);
1239
1240/**
1241 * object_property_set_bool:
1242 * @value: the value to be written to the property
1243 * @name: the name of the property
1244 * @errp: returns an error if this function fails
1245 *
1246 * Writes a bool value to a property.
1247 */
1248void object_property_set_bool(Object *obj, bool value,
1249                              const char *name, Error **errp);
1250
1251/**
1252 * object_property_get_bool:
1253 * @obj: the object
1254 * @name: the name of the property
1255 * @errp: returns an error if this function fails
1256 *
1257 * Returns: the value of the property, converted to a boolean, or NULL if
1258 * an error occurs (including when the property value is not a bool).
1259 */
1260bool object_property_get_bool(Object *obj, const char *name,
1261                              Error **errp);
1262
1263/**
1264 * object_property_set_int:
1265 * @value: the value to be written to the property
1266 * @name: the name of the property
1267 * @errp: returns an error if this function fails
1268 *
1269 * Writes an integer value to a property.
1270 */
1271void object_property_set_int(Object *obj, int64_t value,
1272                             const char *name, Error **errp);
1273
1274/**
1275 * object_property_get_int:
1276 * @obj: the object
1277 * @name: the name of the property
1278 * @errp: returns an error if this function fails
1279 *
1280 * Returns: the value of the property, converted to an integer, or negative if
1281 * an error occurs (including when the property value is not an integer).
1282 */
1283int64_t object_property_get_int(Object *obj, const char *name,
1284                                Error **errp);
1285
1286/**
1287 * object_property_set_uint:
1288 * @value: the value to be written to the property
1289 * @name: the name of the property
1290 * @errp: returns an error if this function fails
1291 *
1292 * Writes an unsigned integer value to a property.
1293 */
1294void object_property_set_uint(Object *obj, uint64_t value,
1295                              const char *name, Error **errp);
1296
1297/**
1298 * object_property_get_uint:
1299 * @obj: the object
1300 * @name: the name of the property
1301 * @errp: returns an error if this function fails
1302 *
1303 * Returns: the value of the property, converted to an unsigned integer, or 0
1304 * an error occurs (including when the property value is not an integer).
1305 */
1306uint64_t object_property_get_uint(Object *obj, const char *name,
1307                                  Error **errp);
1308
1309/**
1310 * object_property_get_enum:
1311 * @obj: the object
1312 * @name: the name of the property
1313 * @typename: the name of the enum data type
1314 * @errp: returns an error if this function fails
1315 *
1316 * Returns: the value of the property, converted to an integer, or
1317 * undefined if an error occurs (including when the property value is not
1318 * an enum).
1319 */
1320int object_property_get_enum(Object *obj, const char *name,
1321                             const char *typename, Error **errp);
1322
1323/**
1324 * object_property_get_uint16List:
1325 * @obj: the object
1326 * @name: the name of the property
1327 * @list: the returned int list
1328 * @errp: returns an error if this function fails
1329 *
1330 * Returns: the value of the property, converted to integers, or
1331 * undefined if an error occurs (including when the property value is not
1332 * an list of integers).
1333 */
1334void object_property_get_uint16List(Object *obj, const char *name,
1335                                    uint16List **list, Error **errp);
1336
1337/**
1338 * object_property_set:
1339 * @obj: the object
1340 * @v: the visitor that will be used to write the property value.  This should
1341 *   be an Input visitor and the data will be first read with @name as the
1342 *   name and then written as the property value.
1343 * @name: the name of the property
1344 * @errp: returns an error if this function fails
1345 *
1346 * Writes a property to a object.
1347 */
1348void object_property_set(Object *obj, Visitor *v, const char *name,
1349                         Error **errp);
1350
1351/**
1352 * object_property_parse:
1353 * @obj: the object
1354 * @string: the string that will be used to parse the property value.
1355 * @name: the name of the property
1356 * @errp: returns an error if this function fails
1357 *
1358 * Parses a string and writes the result into a property of an object.
1359 */
1360void object_property_parse(Object *obj, const char *string,
1361                           const char *name, Error **errp);
1362
1363/**
1364 * object_property_print:
1365 * @obj: the object
1366 * @name: the name of the property
1367 * @human: if true, print for human consumption
1368 * @errp: returns an error if this function fails
1369 *
1370 * Returns a string representation of the value of the property.  The
1371 * caller shall free the string.
1372 */
1373char *object_property_print(Object *obj, const char *name, bool human,
1374                            Error **errp);
1375
1376/**
1377 * object_property_get_type:
1378 * @obj: the object
1379 * @name: the name of the property
1380 * @errp: returns an error if this function fails
1381 *
1382 * Returns:  The type name of the property.
1383 */
1384const char *object_property_get_type(Object *obj, const char *name,
1385                                     Error **errp);
1386
1387/**
1388 * object_get_root:
1389 *
1390 * Returns: the root object of the composition tree
1391 */
1392Object *object_get_root(void);
1393
1394
1395/**
1396 * object_get_objects_root:
1397 *
1398 * Get the container object that holds user created
1399 * object instances. This is the object at path
1400 * "/objects"
1401 *
1402 * Returns: the user object container
1403 */
1404Object *object_get_objects_root(void);
1405
1406/**
1407 * object_get_internal_root:
1408 *
1409 * Get the container object that holds internally used object
1410 * instances.  Any object which is put into this container must not be
1411 * user visible, and it will not be exposed in the QOM tree.
1412 *
1413 * Returns: the internal object container
1414 */
1415Object *object_get_internal_root(void);
1416
1417/**
1418 * object_get_canonical_path_component:
1419 *
1420 * Returns: The final component in the object's canonical path.  The canonical
1421 * path is the path within the composition tree starting from the root.
1422 * %NULL if the object doesn't have a parent (and thus a canonical path).
1423 */
1424gchar *object_get_canonical_path_component(Object *obj);
1425
1426/**
1427 * object_get_canonical_path:
1428 *
1429 * Returns: The canonical path for a object.  This is the path within the
1430 * composition tree starting from the root.
1431 */
1432gchar *object_get_canonical_path(Object *obj);
1433
1434/**
1435 * object_resolve_path:
1436 * @path: the path to resolve
1437 * @ambiguous: returns true if the path resolution failed because of an
1438 *   ambiguous match
1439 *
1440 * There are two types of supported paths--absolute paths and partial paths.
1441 * 
1442 * Absolute paths are derived from the root object and can follow child<> or
1443 * link<> properties.  Since they can follow link<> properties, they can be
1444 * arbitrarily long.  Absolute paths look like absolute filenames and are
1445 * prefixed with a leading slash.
1446 * 
1447 * Partial paths look like relative filenames.  They do not begin with a
1448 * prefix.  The matching rules for partial paths are subtle but designed to make
1449 * specifying objects easy.  At each level of the composition tree, the partial
1450 * path is matched as an absolute path.  The first match is not returned.  At
1451 * least two matches are searched for.  A successful result is only returned if
1452 * only one match is found.  If more than one match is found, a flag is
1453 * returned to indicate that the match was ambiguous.
1454 *
1455 * Returns: The matched object or NULL on path lookup failure.
1456 */
1457Object *object_resolve_path(const char *path, bool *ambiguous);
1458
1459/**
1460 * object_resolve_path_type:
1461 * @path: the path to resolve
1462 * @typename: the type to look for.
1463 * @ambiguous: returns true if the path resolution failed because of an
1464 *   ambiguous match
1465 *
1466 * This is similar to object_resolve_path.  However, when looking for a
1467 * partial path only matches that implement the given type are considered.
1468 * This restricts the search and avoids spuriously flagging matches as
1469 * ambiguous.
1470 *
1471 * For both partial and absolute paths, the return value goes through
1472 * a dynamic cast to @typename.  This is important if either the link,
1473 * or the typename itself are of interface types.
1474 *
1475 * Returns: The matched object or NULL on path lookup failure.
1476 */
1477Object *object_resolve_path_type(const char *path, const char *typename,
1478                                 bool *ambiguous);
1479
1480/**
1481 * object_resolve_path_component:
1482 * @parent: the object in which to resolve the path
1483 * @part: the component to resolve.
1484 *
1485 * This is similar to object_resolve_path with an absolute path, but it
1486 * only resolves one element (@part) and takes the others from @parent.
1487 *
1488 * Returns: The resolved object or NULL on path lookup failure.
1489 */
1490Object *object_resolve_path_component(Object *parent, const gchar *part);
1491
1492/**
1493 * object_property_add_child:
1494 * @obj: the object to add a property to
1495 * @name: the name of the property
1496 * @child: the child object
1497 * @errp: if an error occurs, a pointer to an area to store the error
1498 *
1499 * Child properties form the composition tree.  All objects need to be a child
1500 * of another object.  Objects can only be a child of one object.
1501 *
1502 * There is no way for a child to determine what its parent is.  It is not
1503 * a bidirectional relationship.  This is by design.
1504 *
1505 * The value of a child property as a C string will be the child object's
1506 * canonical path. It can be retrieved using object_property_get_str().
1507 * The child object itself can be retrieved using object_property_get_link().
1508 */
1509void object_property_add_child(Object *obj, const char *name,
1510                               Object *child, Error **errp);
1511
1512typedef enum {
1513    /* Unref the link pointer when the property is deleted */
1514    OBJ_PROP_LINK_STRONG = 0x1,
1515
1516    /* private */
1517    OBJ_PROP_LINK_DIRECT = 0x2,
1518    OBJ_PROP_LINK_CLASS = 0x4,
1519} ObjectPropertyLinkFlags;
1520
1521/**
1522 * object_property_allow_set_link:
1523 *
1524 * The default implementation of the object_property_add_link() check()
1525 * callback function.  It allows the link property to be set and never returns
1526 * an error.
1527 */
1528void object_property_allow_set_link(const Object *, const char *,
1529                                    Object *, Error **);
1530
1531/**
1532 * object_property_add_link:
1533 * @obj: the object to add a property to
1534 * @name: the name of the property
1535 * @type: the qobj type of the link
1536 * @targetp: a pointer to where the link object reference is stored
1537 * @check: callback to veto setting or NULL if the property is read-only
1538 * @flags: additional options for the link
1539 * @errp: if an error occurs, a pointer to an area to store the error
1540 *
1541 * Links establish relationships between objects.  Links are unidirectional
1542 * although two links can be combined to form a bidirectional relationship
1543 * between objects.
1544 *
1545 * Links form the graph in the object model.
1546 *
1547 * The <code>@check()</code> callback is invoked when
1548 * object_property_set_link() is called and can raise an error to prevent the
1549 * link being set.  If <code>@check</code> is NULL, the property is read-only
1550 * and cannot be set.
1551 *
1552 * Ownership of the pointer that @child points to is transferred to the
1553 * link property.  The reference count for <code>*@child</code> is
1554 * managed by the property from after the function returns till the
1555 * property is deleted with object_property_del().  If the
1556 * <code>@flags</code> <code>OBJ_PROP_LINK_STRONG</code> bit is set,
1557 * the reference count is decremented when the property is deleted or
1558 * modified.
1559 */
1560void object_property_add_link(Object *obj, const char *name,
1561                              const char *type, Object **targetp,
1562                              void (*check)(const Object *obj, const char *name,
1563                                            Object *val, Error **errp),
1564                              ObjectPropertyLinkFlags flags,
1565                              Error **errp);
1566
1567ObjectProperty *object_class_property_add_link(ObjectClass *oc,
1568                              const char *name,
1569                              const char *type, ptrdiff_t offset,
1570                              void (*check)(const Object *obj, const char *name,
1571                                            Object *val, Error **errp),
1572                              ObjectPropertyLinkFlags flags,
1573                              Error **errp);
1574
1575/**
1576 * object_property_add_str:
1577 * @obj: the object to add a property to
1578 * @name: the name of the property
1579 * @get: the getter or NULL if the property is write-only.  This function must
1580 *   return a string to be freed by g_free().
1581 * @set: the setter or NULL if the property is read-only
1582 * @errp: if an error occurs, a pointer to an area to store the error
1583 *
1584 * Add a string property using getters/setters.  This function will add a
1585 * property of type 'string'.
1586 */
1587void object_property_add_str(Object *obj, const char *name,
1588                             char *(*get)(Object *, Error **),
1589                             void (*set)(Object *, const char *, Error **),
1590                             Error **errp);
1591
1592ObjectProperty *object_class_property_add_str(ObjectClass *klass,
1593                                   const char *name,
1594                                   char *(*get)(Object *, Error **),
1595                                   void (*set)(Object *, const char *,
1596                                               Error **),
1597                                   Error **errp);
1598
1599/**
1600 * object_property_add_bool:
1601 * @obj: the object to add a property to
1602 * @name: the name of the property
1603 * @get: the getter or NULL if the property is write-only.
1604 * @set: the setter or NULL if the property is read-only
1605 * @errp: if an error occurs, a pointer to an area to store the error
1606 *
1607 * Add a bool property using getters/setters.  This function will add a
1608 * property of type 'bool'.
1609 */
1610void object_property_add_bool(Object *obj, const char *name,
1611                              bool (*get)(Object *, Error **),
1612                              void (*set)(Object *, bool, Error **),
1613                              Error **errp);
1614
1615ObjectProperty *object_class_property_add_bool(ObjectClass *klass,
1616                                    const char *name,
1617                                    bool (*get)(Object *, Error **),
1618                                    void (*set)(Object *, bool, Error **),
1619                                    Error **errp);
1620
1621/**
1622 * object_property_add_enum:
1623 * @obj: the object to add a property to
1624 * @name: the name of the property
1625 * @typename: the name of the enum data type
1626 * @get: the getter or %NULL if the property is write-only.
1627 * @set: the setter or %NULL if the property is read-only
1628 * @errp: if an error occurs, a pointer to an area to store the error
1629 *
1630 * Add an enum property using getters/setters.  This function will add a
1631 * property of type '@typename'.
1632 */
1633void object_property_add_enum(Object *obj, const char *name,
1634                              const char *typename,
1635                              const QEnumLookup *lookup,
1636                              int (*get)(Object *, Error **),
1637                              void (*set)(Object *, int, Error **),
1638                              Error **errp);
1639
1640ObjectProperty *object_class_property_add_enum(ObjectClass *klass,
1641                                    const char *name,
1642                                    const char *typename,
1643                                    const QEnumLookup *lookup,
1644                                    int (*get)(Object *, Error **),
1645                                    void (*set)(Object *, int, Error **),
1646                                    Error **errp);
1647
1648/**
1649 * object_property_add_tm:
1650 * @obj: the object to add a property to
1651 * @name: the name of the property
1652 * @get: the getter or NULL if the property is write-only.
1653 * @errp: if an error occurs, a pointer to an area to store the error
1654 *
1655 * Add a read-only struct tm valued property using a getter function.
1656 * This function will add a property of type 'struct tm'.
1657 */
1658void object_property_add_tm(Object *obj, const char *name,
1659                            void (*get)(Object *, struct tm *, Error **),
1660                            Error **errp);
1661
1662ObjectProperty *object_class_property_add_tm(ObjectClass *klass,
1663                                  const char *name,
1664                                  void (*get)(Object *, struct tm *, Error **),
1665                                  Error **errp);
1666
1667typedef enum {
1668    /* Automatically add a getter to the property */
1669    OBJ_PROP_FLAG_READ = 1 << 0,
1670    /* Automatically add a setter to the property */
1671    OBJ_PROP_FLAG_WRITE = 1 << 1,
1672    /* Automatically add a getter and a setter to the property */
1673    OBJ_PROP_FLAG_READWRITE = (OBJ_PROP_FLAG_READ | OBJ_PROP_FLAG_WRITE),
1674} ObjectPropertyFlags;
1675
1676/**
1677 * object_property_add_uint8_ptr:
1678 * @obj: the object to add a property to
1679 * @name: the name of the property
1680 * @v: pointer to value
1681 * @flags: bitwise-or'd ObjectPropertyFlags
1682 * @errp: if an error occurs, a pointer to an area to store the error
1683 *
1684 * Add an integer property in memory.  This function will add a
1685 * property of type 'uint8'.
1686 */
1687void object_property_add_uint8_ptr(Object *obj, const char *name,
1688                                   const uint8_t *v, ObjectPropertyFlags flags,
1689                                   Error **errp);
1690
1691ObjectProperty *object_class_property_add_uint8_ptr(ObjectClass *klass,
1692                                         const char *name,
1693                                         const uint8_t *v,
1694                                         ObjectPropertyFlags flags,
1695                                         Error **errp);
1696
1697/**
1698 * object_property_add_uint16_ptr:
1699 * @obj: the object to add a property to
1700 * @name: the name of the property
1701 * @v: pointer to value
1702 * @flags: bitwise-or'd ObjectPropertyFlags
1703 * @errp: if an error occurs, a pointer to an area to store the error
1704 *
1705 * Add an integer property in memory.  This function will add a
1706 * property of type 'uint16'.
1707 */
1708void object_property_add_uint16_ptr(Object *obj, const char *name,
1709                                    const uint16_t *v,
1710                                    ObjectPropertyFlags flags,
1711                                    Error **errp);
1712
1713ObjectProperty *object_class_property_add_uint16_ptr(ObjectClass *klass,
1714                                          const char *name,
1715                                          const uint16_t *v,
1716                                          ObjectPropertyFlags flags,
1717                                          Error **errp);
1718
1719/**
1720 * object_property_add_uint32_ptr:
1721 * @obj: the object to add a property to
1722 * @name: the name of the property
1723 * @v: pointer to value
1724 * @flags: bitwise-or'd ObjectPropertyFlags
1725 * @errp: if an error occurs, a pointer to an area to store the error
1726 *
1727 * Add an integer property in memory.  This function will add a
1728 * property of type 'uint32'.
1729 */
1730void object_property_add_uint32_ptr(Object *obj, const char *name,
1731                                    const uint32_t *v,
1732                                    ObjectPropertyFlags flags,
1733                                    Error **errp);
1734
1735ObjectProperty *object_class_property_add_uint32_ptr(ObjectClass *klass,
1736                                          const char *name,
1737                                          const uint32_t *v,
1738                                          ObjectPropertyFlags flags,
1739                                          Error **errp);
1740
1741/**
1742 * object_property_add_uint64_ptr:
1743 * @obj: the object to add a property to
1744 * @name: the name of the property
1745 * @v: pointer to value
1746 * @flags: bitwise-or'd ObjectPropertyFlags
1747 * @errp: if an error occurs, a pointer to an area to store the error
1748 *
1749 * Add an integer property in memory.  This function will add a
1750 * property of type 'uint64'.
1751 */
1752void object_property_add_uint64_ptr(Object *obj, const char *name,
1753                                    const uint64_t *v,
1754                                    ObjectPropertyFlags flags,
1755                                    Error **Errp);
1756
1757ObjectProperty *object_class_property_add_uint64_ptr(ObjectClass *klass,
1758                                          const char *name,
1759                                          const uint64_t *v,
1760                                          ObjectPropertyFlags flags,
1761                                          Error **Errp);
1762
1763/**
1764 * object_property_add_alias:
1765 * @obj: the object to add a property to
1766 * @name: the name of the property
1767 * @target_obj: the object to forward property access to
1768 * @target_name: the name of the property on the forwarded object
1769 * @errp: if an error occurs, a pointer to an area to store the error
1770 *
1771 * Add an alias for a property on an object.  This function will add a property
1772 * of the same type as the forwarded property.
1773 *
1774 * The caller must ensure that <code>@target_obj</code> stays alive as long as
1775 * this property exists.  In the case of a child object or an alias on the same
1776 * object this will be the case.  For aliases to other objects the caller is
1777 * responsible for taking a reference.
1778 */
1779void object_property_add_alias(Object *obj, const char *name,
1780                               Object *target_obj, const char *target_name,
1781                               Error **errp);
1782
1783/**
1784 * object_property_add_const_link:
1785 * @obj: the object to add a property to
1786 * @name: the name of the property
1787 * @target: the object to be referred by the link
1788 * @errp: if an error occurs, a pointer to an area to store the error
1789 *
1790 * Add an unmodifiable link for a property on an object.  This function will
1791 * add a property of type link<TYPE> where TYPE is the type of @target.
1792 *
1793 * The caller must ensure that @target stays alive as long as
1794 * this property exists.  In the case @target is a child of @obj,
1795 * this will be the case.  Otherwise, the caller is responsible for
1796 * taking a reference.
1797 */
1798void object_property_add_const_link(Object *obj, const char *name,
1799                                    Object *target, Error **errp);
1800
1801/**
1802 * object_property_set_description:
1803 * @obj: the object owning the property
1804 * @name: the name of the property
1805 * @description: the description of the property on the object
1806 * @errp: if an error occurs, a pointer to an area to store the error
1807 *
1808 * Set an object property's description.
1809 *
1810 */
1811void object_property_set_description(Object *obj, const char *name,
1812                                     const char *description, Error **errp);
1813void object_class_property_set_description(ObjectClass *klass, const char *name,
1814                                           const char *description,
1815                                           Error **errp);
1816
1817/**
1818 * object_child_foreach:
1819 * @obj: the object whose children will be navigated
1820 * @fn: the iterator function to be called
1821 * @opaque: an opaque value that will be passed to the iterator
1822 *
1823 * Call @fn passing each child of @obj and @opaque to it, until @fn returns
1824 * non-zero.
1825 *
1826 * It is forbidden to add or remove children from @obj from the @fn
1827 * callback.
1828 *
1829 * Returns: The last value returned by @fn, or 0 if there is no child.
1830 */
1831int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
1832                         void *opaque);
1833
1834/**
1835 * object_child_foreach_recursive:
1836 * @obj: the object whose children will be navigated
1837 * @fn: the iterator function to be called
1838 * @opaque: an opaque value that will be passed to the iterator
1839 *
1840 * Call @fn passing each child of @obj and @opaque to it, until @fn returns
1841 * non-zero. Calls recursively, all child nodes of @obj will also be passed
1842 * all the way down to the leaf nodes of the tree. Depth first ordering.
1843 *
1844 * It is forbidden to add or remove children from @obj (or its
1845 * child nodes) from the @fn callback.
1846 *
1847 * Returns: The last value returned by @fn, or 0 if there is no child.
1848 */
1849int object_child_foreach_recursive(Object *obj,
1850                                   int (*fn)(Object *child, void *opaque),
1851                                   void *opaque);
1852/**
1853 * container_get:
1854 * @root: root of the #path, e.g., object_get_root()
1855 * @path: path to the container
1856 *
1857 * Return a container object whose path is @path.  Create more containers
1858 * along the path if necessary.
1859 *
1860 * Returns: the container object.
1861 */
1862Object *container_get(Object *root, const char *path);
1863
1864/**
1865 * object_type_get_instance_size:
1866 * @typename: Name of the Type whose instance_size is required
1867 *
1868 * Returns the instance_size of the given @typename.
1869 */
1870size_t object_type_get_instance_size(const char *typename);
1871
1872/**
1873 * object_property_help:
1874 * @name: the name of the property
1875 * @type: the type of the property
1876 * @defval: the default value
1877 * @description: description of the property
1878 *
1879 * Returns: a user-friendly formatted string describing the property
1880 * for help purposes.
1881 */
1882char *object_property_help(const char *name, const char *type,
1883                           QObject *defval, const char *description);
1884
1885G_DEFINE_AUTOPTR_CLEANUP_FUNC(Object, object_unref)
1886
1887#endif
1888