qom/object.c

   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 #include "qemu/osdep.h"
  14 #include "hw/qdev-core.h"
  15 #include "qapi/error.h"
  16 #include "qom/object.h"
  17 #include "qom/object_interfaces.h"
  18 #include "qemu/cutils.h"
  19 #include "qapi/visitor.h"
  20 #include "qapi/string-input-visitor.h"
  21 #include "qapi/string-output-visitor.h"
  22 #include "qapi/qapi-builtin-visit.h"
  23 #include "qapi/qmp/qerror.h"
  24 #include "trace.h"
  25
  26 /* TODO: replace QObject with a simpler visitor to avoid a dependency
  27  * of the QOM core on QObject?  */
  28 #include "qom/qom-qobject.h"
  29 #include "qapi/qmp/qbool.h"
  30 #include "qapi/qmp/qnum.h"
  31 #include "qapi/qmp/qstring.h"
  32 #include "qemu/error-report.h"
  33
  34 #define MAX_INTERFACES 32
  35
  36 typedef struct InterfaceImpl InterfaceImpl;
  37 typedef struct TypeImpl TypeImpl;
  38
  39 struct InterfaceImpl
  40 {
  41     const char *typename;
  42 };
  43
  44 struct TypeImpl
  45 {
  46     const char *name;
  47
  48     size_t class_size;
  49
  50     size_t instance_size;
  51
  52     void (*class_init)(ObjectClass *klass, void *data);
  53     void (*class_base_init)(ObjectClass *klass, void *data);
  54
  55     void *class_data;
  56
  57     void (*instance_init)(Object *obj);
  58     void (*instance_post_init)(Object *obj);
  59     void (*instance_finalize)(Object *obj);
  60
  61     bool abstract;
  62
  63     const char *parent;
  64     TypeImpl *parent_type;
  65
  66     ObjectClass *class;
  67
  68     int num_interfaces;
  69     InterfaceImpl interfaces[MAX_INTERFACES];
  70 };
  71
  72 static Type type_interface;
  73
  74 static GHashTable *type_table_get(void)
  75 {
  76     static GHashTable *type_table;
  77
  78     if (type_table == NULL) {
  79         type_table = g_hash_table_new(g_str_hash, g_str_equal);
  80     }
  81
  82     return type_table;
  83 }
  84
  85 static bool enumerating_types;
  86
  87 static void type_table_add(TypeImpl *ti)
  88 {
  89     assert(!enumerating_types);
  90     g_hash_table_insert(type_table_get(), (void *)ti->name, ti);
  91 }
  92
  93 static TypeImpl *type_table_lookup(const char *name)
  94 {
  95     return g_hash_table_lookup(type_table_get(), name);
  96 }
  97
  98 static TypeImpl *type_new(const TypeInfo *info)
  99 {
 100     TypeImpl *ti = g_malloc0(sizeof(*ti));
 101     int i;
 102
 103     g_assert(info->name != NULL);
 104
 105     if (type_table_lookup(info->name) != NULL) {
 106         fprintf(stderr, "Registering `%s' which already exists\n", info->name);
 107         abort();
 108     }
 109
 110     ti->name = g_strdup(info->name);
 111     ti->parent = g_strdup(info->parent);
 112
 113     ti->class_size = info->class_size;
 114     ti->instance_size = info->instance_size;
 115
 116     ti->class_init = info->class_init;
 117     ti->class_base_init = info->class_base_init;
 118     ti->class_data = info->class_data;
 119
 120     ti->instance_init = info->instance_init;
 121     ti->instance_post_init = info->instance_post_init;
 122     ti->instance_finalize = info->instance_finalize;
 123
 124     ti->abstract = info->abstract;
 125
 126     for (i = 0; info->interfaces && info->interfaces[i].type; i++) {
 127         ti->interfaces[i].typename = g_strdup(info->interfaces[i].type);
 128     }
 129     ti->num_interfaces = i;
 130
 131     return ti;
 132 }
 133
 134 static TypeImpl *type_register_internal(const TypeInfo *info)
 135 {
 136     TypeImpl *ti;
 137     ti = type_new(info);
 138
 139     type_table_add(ti);
 140     return ti;
 141 }
 142
 143 TypeImpl *type_register(const TypeInfo *info)
 144 {
 145     assert(info->parent);
 146     return type_register_internal(info);
 147 }
 148
 149 TypeImpl *type_register_static(const TypeInfo *info)
 150 {
 151     return type_register(info);
 152 }
 153
 154 void type_register_static_array(const TypeInfo *infos, int nr_infos)
 155 {
 156     int i;
 157
 158     for (i = 0; i < nr_infos; i++) {
 159         type_register_static(&infos[i]);
 160     }
 161 }
 162
 163 static TypeImpl *type_get_by_name(const char *name)
 164 {
 165     if (name == NULL) {
 166         return NULL;
 167     }
 168
 169     return type_table_lookup(name);
 170 }
 171
 172 static TypeImpl *type_get_parent(TypeImpl *type)
 173 {
 174     if (!type->parent_type && type->parent) {
 175         type->parent_type = type_get_by_name(type->parent);
 176         g_assert(type->parent_type != NULL);
 177     }
 178
 179     return type->parent_type;
 180 }
 181
 182 static bool type_has_parent(TypeImpl *type)
 183 {
 184     return (type->parent != NULL);
 185 }
 186
 187 static size_t type_class_get_size(TypeImpl *ti)
 188 {
 189     if (ti->class_size) {
 190         return ti->class_size;
 191     }
 192
 193     if (type_has_parent(ti)) {
 194         return type_class_get_size(type_get_parent(ti));
 195     }
 196
 197     return sizeof(ObjectClass);
 198 }
 199
 200 static size_t type_object_get_size(TypeImpl *ti)
 201 {
 202     if (ti->instance_size) {
 203         return ti->instance_size;
 204     }
 205
 206     if (type_has_parent(ti)) {
 207         return type_object_get_size(type_get_parent(ti));
 208     }
 209
 210     return 0;
 211 }
 212
 213 size_t object_type_get_instance_size(const char *typename)
 214 {
 215     TypeImpl *type = type_get_by_name(typename);
 216
 217     g_assert(type != NULL);
 218     return type_object_get_size(type);
 219 }
 220
 221 static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
 222 {
 223     assert(target_type);
 224
 225     /* Check if target_type is a direct ancestor of type */
 226     while (type) {
 227         if (type == target_type) {
 228             return true;
 229         }
 230
 231         type = type_get_parent(type);
 232     }
 233
 234     return false;
 235 }
 236
 237 static void type_initialize(TypeImpl *ti);
 238
 239 static void type_initialize_interface(TypeImpl *ti, TypeImpl *interface_type,
 240                                       TypeImpl *parent_type)
 241 {
 242     InterfaceClass *new_iface;
 243     TypeInfo info = { };
 244     TypeImpl *iface_impl;
 245
 246     info.parent = parent_type->name;
 247     info.name = g_strdup_printf("%s::%s", ti->name, interface_type->name);
 248     info.abstract = true;
 249
 250     iface_impl = type_new(&info);
 251     iface_impl->parent_type = parent_type;
 252     type_initialize(iface_impl);
 253     g_free((char *)info.name);
 254
 255     new_iface = (InterfaceClass *)iface_impl->class;
 256     new_iface->concrete_class = ti->class;
 257     new_iface->interface_type = interface_type;
 258
 259     ti->class->interfaces = g_slist_append(ti->class->interfaces,
 260                                            iface_impl->class);
 261 }
 262
 263 static void object_property_free(gpointer data)
 264 {
 265     ObjectProperty *prop = data;
 266
 267     g_free(prop->name);
 268     g_free(prop->type);
 269     g_free(prop->description);
 270     g_free(prop);
 271 }
 272
 273 static void type_initialize(TypeImpl *ti)
 274 {
 275     TypeImpl *parent;
 276
 277     if (ti->class) {
 278         return;
 279     }
 280
 281     ti->class_size = type_class_get_size(ti);
 282     ti->instance_size = type_object_get_size(ti);
 283     /* Any type with zero instance_size is implicitly abstract.
 284      * This means interface types are all abstract.
 285      */
 286     if (ti->instance_size == 0) {
 287         ti->abstract = true;
 288     }
 289     if (type_is_ancestor(ti, type_interface)) {
 290         assert(ti->instance_size == 0);
 291         assert(ti->abstract);
 292         assert(!ti->instance_init);
 293         assert(!ti->instance_post_init);
 294         assert(!ti->instance_finalize);
 295         assert(!ti->num_interfaces);
 296     }
 297     ti->class = g_malloc0(ti->class_size);
 298
 299     parent = type_get_parent(ti);
 300     if (parent) {
 301         type_initialize(parent);
 302         GSList *e;
 303         int i;
 304
 305         g_assert(parent->class_size <= ti->class_size);
 306         memcpy(ti->class, parent->class, parent->class_size);
 307         ti->class->interfaces = NULL;
 308         ti->class->properties = g_hash_table_new_full(
 309             g_str_hash, g_str_equal, g_free, object_property_free);
 310
 311         for (e = parent->class->interfaces; e; e = e->next) {
 312             InterfaceClass *iface = e->data;
 313             ObjectClass *klass = OBJECT_CLASS(iface);
 314
 315             type_initialize_interface(ti, iface->interface_type, klass->type);
 316         }
 317
 318         for (i = 0; i < ti->num_interfaces; i++) {
 319             TypeImpl *t = type_get_by_name(ti->interfaces[i].typename);
 320             for (e = ti->class->interfaces; e; e = e->next) {
 321                 TypeImpl *target_type = OBJECT_CLASS(e->data)->type;
 322
 323                 if (type_is_ancestor(target_type, t)) {
 324                     break;
 325                 }
 326             }
 327
 328             if (e) {
 329                 continue;
 330             }
 331
 332             type_initialize_interface(ti, t, t);
 333         }
 334     } else {
 335         ti->class->properties = g_hash_table_new_full(
 336             g_str_hash, g_str_equal, g_free, object_property_free);
 337     }
 338
 339     ti->class->type = ti;
 340
 341     while (parent) {
 342         if (parent->class_base_init) {
 343             parent->class_base_init(ti->class, ti->class_data);
 344         }
 345         parent = type_get_parent(parent);
 346     }
 347
 348     if (ti->class_init) {
 349         ti->class_init(ti->class, ti->class_data);
 350     }
 351 }
 352
 353 static void object_init_with_type(Object *obj, TypeImpl *ti)
 354 {
 355     if (type_has_parent(ti)) {
 356         object_init_with_type(obj, type_get_parent(ti));
 357     }
 358
 359     if (ti->instance_init) {
 360         ti->instance_init(obj);
 361     }
 362 }
 363
 364 static void object_post_init_with_type(Object *obj, TypeImpl *ti)
 365 {
 366     if (ti->instance_post_init) {
 367         ti->instance_post_init(obj);
 368     }
 369
 370     if (type_has_parent(ti)) {
 371         object_post_init_with_type(obj, type_get_parent(ti));
 372     }
 373 }
 374
 375 void object_apply_global_props(Object *obj, const GPtrArray *props, Error **errp)
 376 {
 377     int i;
 378
 379     if (!props) {
 380         return;
 381     }
 382
 383     for (i = 0; i < props->len; i++) {
 384         GlobalProperty *p = g_ptr_array_index(props, i);
 385         Error *err = NULL;
 386
 387         if (object_dynamic_cast(obj, p->driver) == NULL) {
 388             continue;
 389         }
 390         if (p->optional && !object_property_find(obj, p->property, NULL)) {
 391             continue;
 392         }
 393         p->used = true;
 394         object_property_parse(obj, p->value, p->property, &err);
 395         if (err != NULL) {
 396             error_prepend(&err, "can't apply global %s.%s=%s: ",
 397                           p->driver, p->property, p->value);
 398             /*
 399              * If errp != NULL, propagate error and return.
 400              * If errp == NULL, report a warning, but keep going
 401              * with the remaining globals.
 402              */
 403             if (errp) {
 404                 error_propagate(errp, err);
 405                 return;
 406             } else {
 407                 warn_report_err(err);
 408             }
 409         }
 410     }
 411 }
 412
 413 /*
 414  * Global property defaults
 415  * Slot 0: accelerator's global property defaults
 416  * Slot 1: machine's global property defaults
 417  * Each is a GPtrArray of of GlobalProperty.
 418  * Applied in order, later entries override earlier ones.
 419  */
 420 static GPtrArray *object_compat_props[2];
 421
 422 /*
 423  * Set machine's global property defaults to @compat_props.
 424  * May be called at most once.
 425  */
 426 void object_set_machine_compat_props(GPtrArray *compat_props)
 427 {
 428     assert(!object_compat_props[1]);
 429     object_compat_props[1] = compat_props;
 430 }
 431
 432 /*
 433  * Set accelerator's global property defaults to @compat_props.
 434  * May be called at most once.
 435  */
 436 void object_set_accelerator_compat_props(GPtrArray *compat_props)
 437 {
 438     assert(!object_compat_props[0]);
 439     object_compat_props[0] = compat_props;
 440 }
 441
 442 void object_apply_compat_props(Object *obj)
 443 {
 444     int i;
 445
 446     for (i = 0; i < ARRAY_SIZE(object_compat_props); i++) {
 447         object_apply_global_props(obj, object_compat_props[i],
 448                                   &error_abort);
 449     }
 450 }
 451
 452 static void object_initialize_with_type(void *data, size_t size, TypeImpl *type)
 453 {
 454     Object *obj = data;
 455
 456     type_initialize(type);
 457
 458     g_assert(type->instance_size >= sizeof(Object));
 459     g_assert(type->abstract == false);
 460     g_assert(size >= type->instance_size);
 461
 462     memset(obj, 0, type->instance_size);
 463     obj->class = type->class;
 464     object_ref(obj);
 465     obj->properties = g_hash_table_new_full(g_str_hash, g_str_equal,
 466                                             NULL, object_property_free);
 467     object_init_with_type(obj, type);
 468     object_post_init_with_type(obj, type);
 469 }
 470
 471 void object_initialize(void *data, size_t size, const char *typename)
 472 {
 473     TypeImpl *type = type_get_by_name(typename);
 474
 475     if (!type) {
 476         error_report("missing object type '%s'", typename);
 477         abort();
 478     }
 479
 480     object_initialize_with_type(data, size, type);
 481 }
 482
 483 void object_initialize_child(Object *parentobj, const char *propname,
 484                              void *childobj, size_t size, const char *type,
 485                              Error **errp, ...)
 486 {
 487     va_list vargs;
 488
 489     va_start(vargs, errp);
 490     object_initialize_childv(parentobj, propname, childobj, size, type, errp,
 491                              vargs);
 492     va_end(vargs);
 493 }
 494
 495 void object_initialize_childv(Object *parentobj, const char *propname,
 496                               void *childobj, size_t size, const char *type,
 497                               Error **errp, va_list vargs)
 498 {
 499     Error *local_err = NULL;
 500     Object *obj;
 501     UserCreatable *uc;
 502
 503     object_initialize(childobj, size, type);
 504     obj = OBJECT(childobj);
 505
 506     object_set_propv(obj, &local_err, vargs);
 507     if (local_err) {
 508         goto out;
 509     }
 510
 511     object_property_add_child(parentobj, propname, obj, &local_err);
 512     if (local_err) {
 513         goto out;
 514     }
 515
 516     uc = (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE);
 517     if (uc) {
 518         user_creatable_complete(uc, &local_err);
 519         if (local_err) {
 520             object_unparent(obj);
 521             goto out;
 522         }
 523     }
 524
 525     /*
 526      * Since object_property_add_child added a reference to the child object,
 527      * we can drop the reference added by object_initialize(), so the child
 528      * property will own the only reference to the object.
 529      */
 530     object_unref(obj);
 531
 532 out:
 533     if (local_err) {
 534         error_propagate(errp, local_err);
 535         object_unref(obj);
 536     }
 537 }
 538
 539 static inline bool object_property_is_child(ObjectProperty *prop)
 540 {
 541     return strstart(prop->type, "child<", NULL);
 542 }
 543
 544 static void object_property_del_all(Object *obj)
 545 {
 546     ObjectProperty *prop;
 547     GHashTableIter iter;
 548     gpointer key, value;
 549     bool released;
 550
 551     do {
 552         released = false;
 553         g_hash_table_iter_init(&iter, obj->properties);
 554         while (g_hash_table_iter_next(&iter, &key, &value)) {
 555             prop = value;
 556             if (prop->release) {
 557                 prop->release(obj, prop->name, prop->opaque);
 558                 prop->release = NULL;
 559                 released = true;
 560                 break;
 561             }
 562             g_hash_table_iter_remove(&iter);
 563         }
 564     } while (released);
 565
 566     g_hash_table_unref(obj->properties);
 567 }
 568
 569 static void object_property_del_child(Object *obj, Object *child, Error **errp)
 570 {
 571     ObjectProperty *prop;
 572     GHashTableIter iter;
 573     gpointer key, value;
 574
 575     g_hash_table_iter_init(&iter, obj->properties);
 576     while (g_hash_table_iter_next(&iter, &key, &value)) {
 577         prop = value;
 578         if (object_property_is_child(prop) && prop->opaque == child) {
 579             if (prop->release) {
 580                 prop->release(obj, prop->name, prop->opaque);
 581                 prop->release = NULL;
 582             }
 583             break;
 584         }
 585     }
 586     g_hash_table_iter_init(&iter, obj->properties);
 587     while (g_hash_table_iter_next(&iter, &key, &value)) {
 588         prop = value;
 589         if (object_property_is_child(prop) && prop->opaque == child) {
 590             g_hash_table_iter_remove(&iter);
 591             break;
 592         }
 593     }
 594 }
 595
 596 void object_unparent(Object *obj)
 597 {
 598     if (obj->parent) {
 599         object_property_del_child(obj->parent, obj, NULL);
 600     }
 601 }
 602
 603 static void object_deinit(Object *obj, TypeImpl *type)
 604 {
 605     if (type->instance_finalize) {
 606         type->instance_finalize(obj);
 607     }
 608
 609     if (type_has_parent(type)) {
 610         object_deinit(obj, type_get_parent(type));
 611     }
 612 }
 613
 614 static void object_finalize(void *data)
 615 {
 616     Object *obj = data;
 617     TypeImpl *ti = obj->class->type;
 618
 619     object_property_del_all(obj);
 620     object_deinit(obj, ti);
 621
 622     g_assert(obj->ref == 0);
 623     if (obj->free) {
 624         obj->free(obj);
 625     }
 626 }
 627
 628 static Object *object_new_with_type(Type type)
 629 {
 630     Object *obj;
 631
 632     g_assert(type != NULL);
 633     type_initialize(type);
 634
 635     obj = g_malloc(type->instance_size);
 636     object_initialize_with_type(obj, type->instance_size, type);
 637     obj->free = g_free;
 638
 639     return obj;
 640 }
 641
 642 Object *object_new(const char *typename)
 643 {
 644     TypeImpl *ti = type_get_by_name(typename);
 645
 646     return object_new_with_type(ti);
 647 }
 648
 649
 650 Object *object_new_with_props(const char *typename,
 651                               Object *parent,
 652                               const char *id,
 653                               Error **errp,
 654                               ...)
 655 {
 656     va_list vargs;
 657     Object *obj;
 658
 659     va_start(vargs, errp);
 660     obj = object_new_with_propv(typename, parent, id, errp, vargs);
 661     va_end(vargs);
 662
 663     return obj;
 664 }
 665
 666
 667 Object *object_new_with_propv(const char *typename,
 668                               Object *parent,
 669                               const char *id,
 670                               Error **errp,
 671                               va_list vargs)
 672 {
 673     Object *obj;
 674     ObjectClass *klass;
 675     Error *local_err = NULL;
 676     UserCreatable *uc;
 677
 678     klass = object_class_by_name(typename);
 679     if (!klass) {
 680         error_setg(errp, "invalid object type: %s", typename);
 681         return NULL;
 682     }
 683
 684     if (object_class_is_abstract(klass)) {
 685         error_setg(errp, "object type '%s' is abstract", typename);
 686         return NULL;
 687     }
 688     obj = object_new_with_type(klass->type);
 689
 690     if (object_set_propv(obj, &local_err, vargs) < 0) {
 691         goto error;
 692     }
 693
 694     if (id != NULL) {
 695         object_property_add_child(parent, id, obj, &local_err);
 696         if (local_err) {
 697             goto error;
 698         }
 699     }
 700
 701     uc = (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE);
 702     if (uc) {
 703         user_creatable_complete(uc, &local_err);
 704         if (local_err) {
 705             if (id != NULL) {
 706                 object_unparent(obj);
 707             }
 708             goto error;
 709         }
 710     }
 711
 712     object_unref(OBJECT(obj));
 713     return obj;
 714
 715  error:
 716     error_propagate(errp, local_err);
 717     object_unref(obj);
 718     return NULL;
 719 }
 720
 721
 722 int object_set_props(Object *obj,
 723                      Error **errp,
 724                      ...)
 725 {
 726     va_list vargs;
 727     int ret;
 728
 729     va_start(vargs, errp);
 730     ret = object_set_propv(obj, errp, vargs);
 731     va_end(vargs);
 732
 733     return ret;
 734 }
 735
 736
 737 int object_set_propv(Object *obj,
 738                      Error **errp,
 739                      va_list vargs)
 740 {
 741     const char *propname;
 742     Error *local_err = NULL;
 743
 744     propname = va_arg(vargs, char *);
 745     while (propname != NULL) {
 746         const char *value = va_arg(vargs, char *);
 747
 748         g_assert(value != NULL);
 749         object_property_parse(obj, value, propname, &local_err);
 750         if (local_err) {
 751             error_propagate(errp, local_err);
 752             return -1;
 753         }
 754         propname = va_arg(vargs, char *);
 755     }
 756
 757     return 0;
 758 }
 759
 760
 761 Object *object_dynamic_cast(Object *obj, const char *typename)
 762 {
 763     if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
 764         return obj;
 765     }
 766
 767     return NULL;
 768 }
 769
 770 Object *object_dynamic_cast_assert(Object *obj, const char *typename,
 771                                    const char *file, int line, const char *func)
 772 {
 773     trace_object_dynamic_cast_assert(obj ? obj->class->type->name : "(null)",
 774                                      typename, file, line, func);
 775
 776 #ifdef CONFIG_QOM_CAST_DEBUG
 777     int i;
 778     Object *inst;
 779
 780     for (i = 0; obj && i < OBJECT_CLASS_CAST_CACHE; i++) {
 781         if (atomic_read(&obj->class->object_cast_cache[i]) == typename) {
 782             goto out;
 783         }
 784     }
 785
 786     inst = object_dynamic_cast(obj, typename);
 787
 788     if (!inst && obj) {
 789         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
 790                 file, line, func, obj, typename);
 791         abort();
 792     }
 793
 794     assert(obj == inst);
 795
 796     if (obj && obj == inst) {
 797         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
 798             atomic_set(&obj->class->object_cast_cache[i - 1],
 799                        atomic_read(&obj->class->object_cast_cache[i]));
 800         }
 801         atomic_set(&obj->class->object_cast_cache[i - 1], typename);
 802     }
 803
 804 out:
 805 #endif
 806     return obj;
 807 }
 808
 809 ObjectClass *object_class_dynamic_cast(ObjectClass *class,
 810                                        const char *typename)
 811 {
 812     ObjectClass *ret = NULL;
 813     TypeImpl *target_type;
 814     TypeImpl *type;
 815
 816     if (!class) {
 817         return NULL;
 818     }
 819
 820     /* A simple fast path that can trigger a lot for leaf classes.  */
 821     type = class->type;
 822     if (type->name == typename) {
 823         return class;
 824     }
 825
 826     target_type = type_get_by_name(typename);
 827     if (!target_type) {
 828         /* target class type unknown, so fail the cast */
 829         return NULL;
 830     }
 831
 832     if (type->class->interfaces &&
 833             type_is_ancestor(target_type, type_interface)) {
 834         int found = 0;
 835         GSList *i;
 836
 837         for (i = class->interfaces; i; i = i->next) {
 838             ObjectClass *target_class = i->data;
 839
 840             if (type_is_ancestor(target_class->type, target_type)) {
 841                 ret = target_class;
 842                 found++;
 843             }
 844          }
 845
 846         /* The match was ambiguous, don't allow a cast */
 847         if (found > 1) {
 848             ret = NULL;
 849         }
 850     } else if (type_is_ancestor(type, target_type)) {
 851         ret = class;
 852     }
 853
 854     return ret;
 855 }
 856
 857 ObjectClass *object_class_dynamic_cast_assert(ObjectClass *class,
 858                                               const char *typename,
 859                                               const char *file, int line,
 860                                               const char *func)
 861 {
 862     ObjectClass *ret;
 863
 864     trace_object_class_dynamic_cast_assert(class ? class->type->name : "(null)",
 865                                            typename, file, line, func);
 866
 867 #ifdef CONFIG_QOM_CAST_DEBUG
 868     int i;
 869
 870     for (i = 0; class && i < OBJECT_CLASS_CAST_CACHE; i++) {
 871         if (atomic_read(&class->class_cast_cache[i]) == typename) {
 872             ret = class;
 873             goto out;
 874         }
 875     }
 876 #else
 877     if (!class || !class->interfaces) {
 878         return class;
 879     }
 880 #endif
 881
 882     ret = object_class_dynamic_cast(class, typename);
 883     if (!ret && class) {
 884         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
 885                 file, line, func, class, typename);
 886         abort();
 887     }
 888
 889 #ifdef CONFIG_QOM_CAST_DEBUG
 890     if (class && ret == class) {
 891         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
 892             atomic_set(&class->class_cast_cache[i - 1],
 893                        atomic_read(&class->class_cast_cache[i]));
 894         }
 895         atomic_set(&class->class_cast_cache[i - 1], typename);
 896     }
 897 out:
 898 #endif
 899     return ret;
 900 }
 901
 902 const char *object_get_typename(const Object *obj)
 903 {
 904     return obj->class->type->name;
 905 }
 906
 907 ObjectClass *object_get_class(Object *obj)
 908 {
 909     return obj->class;
 910 }
 911
 912 bool object_class_is_abstract(ObjectClass *klass)
 913 {
 914     return klass->type->abstract;
 915 }
 916
 917 const char *object_class_get_name(ObjectClass *klass)
 918 {
 919     return klass->type->name;
 920 }
 921
 922 ObjectClass *object_class_by_name(const char *typename)
 923 {
 924     TypeImpl *type = type_get_by_name(typename);
 925
 926     if (!type) {
 927         return NULL;
 928     }
 929
 930     type_initialize(type);
 931
 932     return type->class;
 933 }
 934
 935 ObjectClass *object_class_get_parent(ObjectClass *class)
 936 {
 937     TypeImpl *type = type_get_parent(class->type);
 938
 939     if (!type) {
 940         return NULL;
 941     }
 942
 943     type_initialize(type);
 944
 945     return type->class;
 946 }
 947
 948 typedef struct OCFData
 949 {
 950     void (*fn)(ObjectClass *klass, void *opaque);
 951     const char *implements_type;
 952     bool include_abstract;
 953     void *opaque;
 954 } OCFData;
 955
 956 static void object_class_foreach_tramp(gpointer key, gpointer value,
 957                                        gpointer opaque)
 958 {
 959     OCFData *data = opaque;
 960     TypeImpl *type = value;
 961     ObjectClass *k;
 962
 963     type_initialize(type);
 964     k = type->class;
 965
 966     if (!data->include_abstract && type->abstract) {
 967         return;
 968     }
 969
 970     if (data->implements_type &&
 971         !object_class_dynamic_cast(k, data->implements_type)) {
 972         return;
 973     }
 974
 975     data->fn(k, data->opaque);
 976 }
 977
 978 void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
 979                           const char *implements_type, bool include_abstract,
 980                           void *opaque)
 981 {
 982     OCFData data = { fn, implements_type, include_abstract, opaque };
 983
 984     enumerating_types = true;
 985     g_hash_table_foreach(type_table_get(), object_class_foreach_tramp, &data);
 986     enumerating_types = false;
 987 }
 988
 989 static int do_object_child_foreach(Object *obj,
 990                                    int (*fn)(Object *child, void *opaque),
 991                                    void *opaque, bool recurse)
 992 {
 993     GHashTableIter iter;
 994     ObjectProperty *prop;
 995     int ret = 0;
 996
 997     g_hash_table_iter_init(&iter, obj->properties);
 998     while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
 999         if (object_property_is_child(prop)) {
1000             Object *child = prop->opaque;
1001
1002             ret = fn(child, opaque);
1003             if (ret != 0) {
1004                 break;
1005             }
1006             if (recurse) {
1007                 do_object_child_foreach(child, fn, opaque, true);
1008             }
1009         }
1010     }
1011     return ret;
1012 }
1013
1014 int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
1015                          void *opaque)
1016 {
1017     return do_object_child_foreach(obj, fn, opaque, false);
1018 }
1019
1020 int object_child_foreach_recursive(Object *obj,
1021                                    int (*fn)(Object *child, void *opaque),
1022                                    void *opaque)
1023 {
1024     return do_object_child_foreach(obj, fn, opaque, true);
1025 }
1026
1027 static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
1028 {
1029     GSList **list = opaque;
1030
1031     *list = g_slist_prepend(*list, klass);
1032 }
1033
1034 GSList *object_class_get_list(const char *implements_type,
1035                               bool include_abstract)
1036 {
1037     GSList *list = NULL;
1038
1039     object_class_foreach(object_class_get_list_tramp,
1040                          implements_type, include_abstract, &list);
1041     return list;
1042 }
1043
1044 static gint object_class_cmp(gconstpointer a, gconstpointer b)
1045 {
1046     return strcasecmp(object_class_get_name((ObjectClass *)a),
1047                       object_class_get_name((ObjectClass *)b));
1048 }
1049
1050 GSList *object_class_get_list_sorted(const char *implements_type,
1051                                      bool include_abstract)
1052 {
1053     return g_slist_sort(object_class_get_list(implements_type, include_abstract),
1054                         object_class_cmp);
1055 }
1056
1057 void object_ref(Object *obj)
1058 {
1059     if (!obj) {
1060         return;
1061     }
1062     atomic_inc(&obj->ref);
1063 }
1064
1065 void object_unref(Object *obj)
1066 {
1067     if (!obj) {
1068         return;
1069     }
1070     g_assert(obj->ref > 0);
1071
1072     /* parent always holds a reference to its children */
1073     if (atomic_fetch_dec(&obj->ref) == 1) {
1074         object_finalize(obj);
1075     }
1076 }
1077
1078 ObjectProperty *
1079 object_property_add(Object *obj, const char *name, const char *type,
1080                     ObjectPropertyAccessor *get,
1081                     ObjectPropertyAccessor *set,
1082                     ObjectPropertyRelease *release,
1083                     void *opaque, Error **errp)
1084 {
1085     ObjectProperty *prop;
1086     size_t name_len = strlen(name);
1087
1088     if (name_len >= 3 && !memcmp(name + name_len - 3, "[*]", 4)) {
1089         int i;
1090         ObjectProperty *ret;
1091         char *name_no_array = g_strdup(name);
1092
1093         name_no_array[name_len - 3] = '\0';
1094         for (i = 0; ; ++i) {
1095             char *full_name = g_strdup_printf("%s[%d]", name_no_array, i);
1096
1097             ret = object_property_add(obj, full_name, type, get, set,
1098                                       release, opaque, NULL);
1099             g_free(full_name);
1100             if (ret) {
1101                 break;
1102             }
1103         }
1104         g_free(name_no_array);
1105         return ret;
1106     }
1107
1108     if (object_property_find(obj, name, NULL) != NULL) {
1109         error_setg(errp, "attempt to add duplicate property '%s' to object (type '%s')",
1110                    name, object_get_typename(obj));
1111         return NULL;
1112     }
1113
1114     prop = g_malloc0(sizeof(*prop));
1115
1116     prop->name = g_strdup(name);
1117     prop->type = g_strdup(type);
1118
1119     prop->get = get;
1120     prop->set = set;
1121     prop->release = release;
1122     prop->opaque = opaque;
1123
1124     g_hash_table_insert(obj->properties, prop->name, prop);
1125     return prop;
1126 }
1127
1128 ObjectProperty *
1129 object_class_property_add(ObjectClass *klass,
1130                           const char *name,
1131                           const char *type,
1132                           ObjectPropertyAccessor *get,
1133                           ObjectPropertyAccessor *set,
1134                           ObjectPropertyRelease *release,
1135                           void *opaque,
1136                           Error **errp)
1137 {
1138     ObjectProperty *prop;
1139
1140     if (object_class_property_find(klass, name, NULL) != NULL) {
1141         error_setg(errp, "attempt to add duplicate property '%s' to class (type '%s')",
1142                    name, object_class_get_name(klass));
1143         return NULL;
1144     }
1145
1146     prop = g_malloc0(sizeof(*prop));
1147
1148     prop->name = g_strdup(name);
1149     prop->type = g_strdup(type);
1150
1151     prop->get = get;
1152     prop->set = set;
1153     prop->release = release;
1154     prop->opaque = opaque;
1155
1156     g_hash_table_insert(klass->properties, g_strdup(name), prop);
1157
1158     return prop;
1159 }
1160
1161 ObjectProperty *object_property_find(Object *obj, const char *name,
1162                                      Error **errp)
1163 {
1164     ObjectProperty *prop;
1165     ObjectClass *klass = object_get_class(obj);
1166
1167     prop = object_class_property_find(klass, name, NULL);
1168     if (prop) {
1169         return prop;
1170     }
1171
1172     prop = g_hash_table_lookup(obj->properties, name);
1173     if (prop) {
1174         return prop;
1175     }
1176
1177     error_setg(errp, "Property '.%s' not found", name);
1178     return NULL;
1179 }
1180
1181 void object_property_iter_init(ObjectPropertyIterator *iter,
1182                                Object *obj)
1183 {
1184     g_hash_table_iter_init(&iter->iter, obj->properties);
1185     iter->nextclass = object_get_class(obj);
1186 }
1187
1188 ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter)
1189 {
1190     gpointer key, val;
1191     while (!g_hash_table_iter_next(&iter->iter, &key, &val)) {
1192         if (!iter->nextclass) {
1193             return NULL;
1194         }
1195         g_hash_table_iter_init(&iter->iter, iter->nextclass->properties);
1196         iter->nextclass = object_class_get_parent(iter->nextclass);
1197     }
1198     return val;
1199 }
1200
1201 void object_class_property_iter_init(ObjectPropertyIterator *iter,
1202                                      ObjectClass *klass)
1203 {
1204     g_hash_table_iter_init(&iter->iter, klass->properties);
1205     iter->nextclass = object_class_get_parent(klass);
1206 }
1207
1208 ObjectProperty *object_class_property_find(ObjectClass *klass, const char *name,
1209                                            Error **errp)
1210 {
1211     ObjectProperty *prop;
1212     ObjectClass *parent_klass;
1213
1214     parent_klass = object_class_get_parent(klass);
1215     if (parent_klass) {
1216         prop = object_class_property_find(parent_klass, name, NULL);
1217         if (prop) {
1218             return prop;
1219         }
1220     }
1221
1222     prop = g_hash_table_lookup(klass->properties, name);
1223     if (!prop) {
1224         error_setg(errp, "Property '.%s' not found", name);
1225     }
1226     return prop;
1227 }
1228
1229 void object_property_del(Object *obj, const char *name, Error **errp)
1230 {
1231     ObjectProperty *prop = g_hash_table_lookup(obj->properties, name);
1232
1233     if (!prop) {
1234         error_setg(errp, "Property '.%s' not found", name);
1235         return;
1236     }
1237
1238     if (prop->release) {
1239         prop->release(obj, name, prop->opaque);
1240     }
1241     g_hash_table_remove(obj->properties, name);
1242 }
1243
1244 void object_property_get(Object *obj, Visitor *v, const char *name,
1245                          Error **errp)
1246 {
1247     ObjectProperty *prop = object_property_find(obj, name, errp);
1248     if (prop == NULL) {
1249         return;
1250     }
1251
1252     if (!prop->get) {
1253         error_setg(errp, QERR_PERMISSION_DENIED);
1254     } else {
1255         prop->get(obj, v, name, prop->opaque, errp);
1256     }
1257 }
1258
1259 void object_property_set(Object *obj, Visitor *v, const char *name,
1260                          Error **errp)
1261 {
1262     ObjectProperty *prop = object_property_find(obj, name, errp);
1263     if (prop == NULL) {
1264         return;
1265     }
1266
1267     if (!prop->set) {
1268         error_setg(errp, QERR_PERMISSION_DENIED);
1269     } else {
1270         prop->set(obj, v, name, prop->opaque, errp);
1271     }
1272 }
1273
1274 void object_property_set_str(Object *obj, const char *value,
1275                              const char *name, Error **errp)
1276 {
1277     QString *qstr = qstring_from_str(value);
1278     object_property_set_qobject(obj, QOBJECT(qstr), name, errp);
1279
1280     qobject_unref(qstr);
1281 }
1282
1283 char *object_property_get_str(Object *obj, const char *name,
1284                               Error **errp)
1285 {
1286     QObject *ret = object_property_get_qobject(obj, name, errp);
1287     char *retval;
1288
1289     if (!ret) {
1290         return NULL;
1291     }
1292
1293     retval = g_strdup(qobject_get_try_str(ret));
1294     if (!retval) {
1295         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name, "string");
1296     }
1297
1298     qobject_unref(ret);
1299     return retval;
1300 }
1301
1302 void object_property_set_link(Object *obj, Object *value,
1303                               const char *name, Error **errp)
1304 {
1305     if (value) {
1306         gchar *path = object_get_canonical_path(value);
1307         object_property_set_str(obj, path, name, errp);
1308         g_free(path);
1309     } else {
1310         object_property_set_str(obj, "", name, errp);
1311     }
1312 }
1313
1314 Object *object_property_get_link(Object *obj, const char *name,
1315                                  Error **errp)
1316 {
1317     char *str = object_property_get_str(obj, name, errp);
1318     Object *target = NULL;
1319
1320     if (str && *str) {
1321         target = object_resolve_path(str, NULL);
1322         if (!target) {
1323             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1324                       "Device '%s' not found", str);
1325         }
1326     }
1327
1328     g_free(str);
1329     return target;
1330 }
1331
1332 void object_property_set_bool(Object *obj, bool value,
1333                               const char *name, Error **errp)
1334 {
1335     QBool *qbool = qbool_from_bool(value);
1336     object_property_set_qobject(obj, QOBJECT(qbool), name, errp);
1337
1338     qobject_unref(qbool);
1339 }
1340
1341 bool object_property_get_bool(Object *obj, const char *name,
1342                               Error **errp)
1343 {
1344     QObject *ret = object_property_get_qobject(obj, name, errp);
1345     QBool *qbool;
1346     bool retval;
1347
1348     if (!ret) {
1349         return false;
1350     }
1351     qbool = qobject_to(QBool, ret);
1352     if (!qbool) {
1353         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name, "boolean");
1354         retval = false;
1355     } else {
1356         retval = qbool_get_bool(qbool);
1357     }
1358
1359     qobject_unref(ret);
1360     return retval;
1361 }
1362
1363 void object_property_set_int(Object *obj, int64_t value,
1364                              const char *name, Error **errp)
1365 {
1366     QNum *qnum = qnum_from_int(value);
1367     object_property_set_qobject(obj, QOBJECT(qnum), name, errp);
1368
1369     qobject_unref(qnum);
1370 }
1371
1372 int64_t object_property_get_int(Object *obj, const char *name,
1373                                 Error **errp)
1374 {
1375     QObject *ret = object_property_get_qobject(obj, name, errp);
1376     QNum *qnum;
1377     int64_t retval;
1378
1379     if (!ret) {
1380         return -1;
1381     }
1382
1383     qnum = qobject_to(QNum, ret);
1384     if (!qnum || !qnum_get_try_int(qnum, &retval)) {
1385         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name, "int");
1386         retval = -1;
1387     }
1388
1389     qobject_unref(ret);
1390     return retval;
1391 }
1392
1393 void object_property_set_uint(Object *obj, uint64_t value,
1394                               const char *name, Error **errp)
1395 {
1396     QNum *qnum = qnum_from_uint(value);
1397
1398     object_property_set_qobject(obj, QOBJECT(qnum), name, errp);
1399     qobject_unref(qnum);
1400 }
1401
1402 uint64_t object_property_get_uint(Object *obj, const char *name,
1403                                   Error **errp)
1404 {
1405     QObject *ret = object_property_get_qobject(obj, name, errp);
1406     QNum *qnum;
1407     uint64_t retval;
1408
1409     if (!ret) {
1410         return 0;
1411     }
1412     qnum = qobject_to(QNum, ret);
1413     if (!qnum || !qnum_get_try_uint(qnum, &retval)) {
1414         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name, "uint");
1415         retval = 0;
1416     }
1417
1418     qobject_unref(ret);
1419     return retval;
1420 }
1421
1422 typedef struct EnumProperty {
1423     const QEnumLookup *lookup;
1424     int (*get)(Object *, Error **);
1425     void (*set)(Object *, int, Error **);
1426 } EnumProperty;
1427
1428 int object_property_get_enum(Object *obj, const char *name,
1429                              const char *typename, Error **errp)
1430 {
1431     Error *err = NULL;
1432     Visitor *v;
1433     char *str;
1434     int ret;
1435     ObjectProperty *prop = object_property_find(obj, name, errp);
1436     EnumProperty *enumprop;
1437
1438     if (prop == NULL) {
1439         return 0;
1440     }
1441
1442     if (!g_str_equal(prop->type, typename)) {
1443         error_setg(errp, "Property %s on %s is not '%s' enum type",
1444                    name, object_class_get_name(
1445                        object_get_class(obj)), typename);
1446         return 0;
1447     }
1448
1449     enumprop = prop->opaque;
1450
1451     v = string_output_visitor_new(false, &str);
1452     object_property_get(obj, v, name, &err);
1453     if (err) {
1454         error_propagate(errp, err);
1455         visit_free(v);
1456         return 0;
1457     }
1458     visit_complete(v, &str);
1459     visit_free(v);
1460     v = string_input_visitor_new(str);
1461     visit_type_enum(v, name, &ret, enumprop->lookup, errp);
1462
1463     g_free(str);
1464     visit_free(v);
1465
1466     return ret;
1467 }
1468
1469 void object_property_get_uint16List(Object *obj, const char *name,
1470                                     uint16List **list, Error **errp)
1471 {
1472     Error *err = NULL;
1473     Visitor *v;
1474     char *str;
1475
1476     v = string_output_visitor_new(false, &str);
1477     object_property_get(obj, v, name, &err);
1478     if (err) {
1479         error_propagate(errp, err);
1480         goto out;
1481     }
1482     visit_complete(v, &str);
1483     visit_free(v);
1484     v = string_input_visitor_new(str);
1485     visit_type_uint16List(v, NULL, list, errp);
1486
1487     g_free(str);
1488 out:
1489     visit_free(v);
1490 }
1491
1492 void object_property_parse(Object *obj, const char *string,
1493                            const char *name, Error **errp)
1494 {
1495     Visitor *v = string_input_visitor_new(string);
1496     object_property_set(obj, v, name, errp);
1497     visit_free(v);
1498 }
1499
1500 char *object_property_print(Object *obj, const char *name, bool human,
1501                             Error **errp)
1502 {
1503     Visitor *v;
1504     char *string = NULL;
1505     Error *local_err = NULL;
1506
1507     v = string_output_visitor_new(human, &string);
1508     object_property_get(obj, v, name, &local_err);
1509     if (local_err) {
1510         error_propagate(errp, local_err);
1511         goto out;
1512     }
1513
1514     visit_complete(v, &string);
1515
1516 out:
1517     visit_free(v);
1518     return string;
1519 }
1520
1521 const char *object_property_get_type(Object *obj, const char *name, Error **errp)
1522 {
1523     ObjectProperty *prop = object_property_find(obj, name, errp);
1524     if (prop == NULL) {
1525         return NULL;
1526     }
1527
1528     return prop->type;
1529 }
1530
1531 Object *object_get_root(void)
1532 {
1533     static Object *root;
1534
1535     if (!root) {
1536         root = object_new("container");
1537     }
1538
1539     return root;
1540 }
1541
1542 Object *object_get_objects_root(void)
1543 {
1544     return container_get(object_get_root(), "/objects");
1545 }
1546
1547 Object *object_get_internal_root(void)
1548 {
1549     static Object *internal_root;
1550
1551     if (!internal_root) {
1552         internal_root = object_new("container");
1553     }
1554
1555     return internal_root;
1556 }
1557
1558 static void object_get_child_property(Object *obj, Visitor *v,
1559                                       const char *name, void *opaque,
1560                                       Error **errp)
1561 {
1562     Object *child = opaque;
1563     gchar *path;
1564
1565     path = object_get_canonical_path(child);
1566     visit_type_str(v, name, &path, errp);
1567     g_free(path);
1568 }
1569
1570 static Object *object_resolve_child_property(Object *parent, void *opaque, const gchar *part)
1571 {
1572     return opaque;
1573 }
1574
1575 static void object_finalize_child_property(Object *obj, const char *name,
1576                                            void *opaque)
1577 {
1578     Object *child = opaque;
1579
1580     if (child->class->unparent) {
1581         (child->class->unparent)(child);
1582     }
1583     child->parent = NULL;
1584     object_unref(child);
1585 }
1586
1587 void object_property_add_child(Object *obj, const char *name,
1588                                Object *child, Error **errp)
1589 {
1590     Error *local_err = NULL;
1591     gchar *type;
1592     ObjectProperty *op;
1593
1594     if (child->parent != NULL) {
1595         error_setg(errp, "child object is already parented");
1596         return;
1597     }
1598
1599     type = g_strdup_printf("child<%s>", object_get_typename(OBJECT(child)));
1600
1601     op = object_property_add(obj, name, type, object_get_child_property, NULL,
1602                              object_finalize_child_property, child, &local_err);
1603     if (local_err) {
1604         error_propagate(errp, local_err);
1605         goto out;
1606     }
1607
1608     op->resolve = object_resolve_child_property;
1609     object_ref(child);
1610     child->parent = obj;
1611
1612 out:
1613     g_free(type);
1614 }
1615
1616 void object_property_allow_set_link(const Object *obj, const char *name,
1617                                     Object *val, Error **errp)
1618 {
1619     /* Allow the link to be set, always */
1620 }
1621
1622 typedef struct {
1623     Object **child;
1624     void (*check)(const Object *, const char *, Object *, Error **);
1625     ObjectPropertyLinkFlags flags;
1626 } LinkProperty;
1627
1628 static void object_get_link_property(Object *obj, Visitor *v,
1629                                      const char *name, void *opaque,
1630                                      Error **errp)
1631 {
1632     LinkProperty *lprop = opaque;
1633     Object **child = lprop->child;
1634     gchar *path;
1635
1636     if (*child) {
1637         path = object_get_canonical_path(*child);
1638         visit_type_str(v, name, &path, errp);
1639         g_free(path);
1640     } else {
1641         path = (gchar *)"";
1642         visit_type_str(v, name, &path, errp);
1643     }
1644 }
1645
1646 /*
1647  * object_resolve_link:
1648  *
1649  * Lookup an object and ensure its type matches the link property type.  This
1650  * is similar to object_resolve_path() except type verification against the
1651  * link property is performed.
1652  *
1653  * Returns: The matched object or NULL on path lookup failures.
1654  */
1655 static Object *object_resolve_link(Object *obj, const char *name,
1656                                    const char *path, Error **errp)
1657 {
1658     const char *type;
1659     gchar *target_type;
1660     bool ambiguous = false;
1661     Object *target;
1662
1663     /* Go from link<FOO> to FOO.  */
1664     type = object_property_get_type(obj, name, NULL);
1665     target_type = g_strndup(&type[5], strlen(type) - 6);
1666     target = object_resolve_path_type(path, target_type, &ambiguous);
1667
1668     if (ambiguous) {
1669         error_setg(errp, "Path '%s' does not uniquely identify an object",
1670                    path);
1671     } else if (!target) {
1672         target = object_resolve_path(path, &ambiguous);
1673         if (target || ambiguous) {
1674             error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
1675         } else {
1676             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1677                       "Device '%s' not found", path);
1678         }
1679         target = NULL;
1680     }
1681     g_free(target_type);
1682
1683     return target;
1684 }
1685
1686 static void object_set_link_property(Object *obj, Visitor *v,
1687                                      const char *name, void *opaque,
1688                                      Error **errp)
1689 {
1690     Error *local_err = NULL;
1691     LinkProperty *prop = opaque;
1692     Object **child = prop->child;
1693     Object *old_target = *child;
1694     Object *new_target = NULL;
1695     char *path = NULL;
1696
1697     visit_type_str(v, name, &path, &local_err);
1698
1699     if (!local_err && strcmp(path, "") != 0) {
1700         new_target = object_resolve_link(obj, name, path, &local_err);
1701     }
1702
1703     g_free(path);
1704     if (local_err) {
1705         error_propagate(errp, local_err);
1706         return;
1707     }
1708
1709     prop->check(obj, name, new_target, &local_err);
1710     if (local_err) {
1711         error_propagate(errp, local_err);
1712         return;
1713     }
1714
1715     *child = new_target;
1716     if (prop->flags == OBJ_PROP_LINK_STRONG) {
1717         object_ref(new_target);
1718         object_unref(old_target);
1719     }
1720 }
1721
1722 static Object *object_resolve_link_property(Object *parent, void *opaque, const gchar *part)
1723 {
1724     LinkProperty *lprop = opaque;
1725
1726     return *lprop->child;
1727 }
1728
1729 static void object_release_link_property(Object *obj, const char *name,
1730                                          void *opaque)
1731 {
1732     LinkProperty *prop = opaque;
1733
1734     if ((prop->flags & OBJ_PROP_LINK_STRONG) && *prop->child) {
1735         object_unref(*prop->child);
1736     }
1737     g_free(prop);
1738 }
1739
1740 void object_property_add_link(Object *obj, const char *name,
1741                               const char *type, Object **child,
1742                               void (*check)(const Object *, const char *,
1743                                             Object *, Error **),
1744                               ObjectPropertyLinkFlags flags,
1745                               Error **errp)
1746 {
1747     Error *local_err = NULL;
1748     LinkProperty *prop = g_malloc(sizeof(*prop));
1749     gchar *full_type;
1750     ObjectProperty *op;
1751
1752     prop->child = child;
1753     prop->check = check;
1754     prop->flags = flags;
1755
1756     full_type = g_strdup_printf("link<%s>", type);
1757
1758     op = object_property_add(obj, name, full_type,
1759                              object_get_link_property,
1760                              check ? object_set_link_property : NULL,
1761                              object_release_link_property,
1762                              prop,
1763                              &local_err);
1764     if (local_err) {
1765         error_propagate(errp, local_err);
1766         g_free(prop);
1767         goto out;
1768     }
1769
1770     op->resolve = object_resolve_link_property;
1771
1772 out:
1773     g_free(full_type);
1774 }
1775
1776 void object_property_add_const_link(Object *obj, const char *name,
1777                                     Object *target, Error **errp)
1778 {
1779     char *link_type;
1780     ObjectProperty *op;
1781
1782     link_type = g_strdup_printf("link<%s>", object_get_typename(target));
1783     op = object_property_add(obj, name, link_type,
1784                              object_get_child_property, NULL,
1785                              NULL, target, errp);
1786     if (op != NULL) {
1787         op->resolve = object_resolve_child_property;
1788     }
1789     g_free(link_type);
1790 }
1791
1792 gchar *object_get_canonical_path_component(Object *obj)
1793 {
1794     ObjectProperty *prop = NULL;
1795     GHashTableIter iter;
1796
1797     if (obj->parent == NULL) {
1798         return NULL;
1799     }
1800
1801     g_hash_table_iter_init(&iter, obj->parent->properties);
1802     while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
1803         if (!object_property_is_child(prop)) {
1804             continue;
1805         }
1806
1807         if (prop->opaque == obj) {
1808             return g_strdup(prop->name);
1809         }
1810     }
1811
1812     /* obj had a parent but was not a child, should never happen */
1813     g_assert_not_reached();
1814     return NULL;
1815 }
1816
1817 gchar *object_get_canonical_path(Object *obj)
1818 {
1819     Object *root = object_get_root();
1820     char *newpath, *path = NULL;
1821
1822     if (obj == root) {
1823         return g_strdup("/");
1824     }
1825
1826     do {
1827         char *component = object_get_canonical_path_component(obj);
1828
1829         if (!component) {
1830             /* A canonical path must be complete, so discard what was
1831              * collected so far.
1832              */
1833             g_free(path);
1834             return NULL;
1835         }
1836
1837         newpath = g_strdup_printf("/%s%s", component, path ? path : "");
1838         g_free(path);
1839         g_free(component);
1840         path = newpath;
1841         obj = obj->parent;
1842     } while (obj != root);
1843
1844     return path;
1845 }
1846
1847 Object *object_resolve_path_component(Object *parent, const gchar *part)
1848 {
1849     ObjectProperty *prop = object_property_find(parent, part, NULL);
1850     if (prop == NULL) {
1851         return NULL;
1852     }
1853
1854     if (prop->resolve) {
1855         return prop->resolve(parent, prop->opaque, part);
1856     } else {
1857         return NULL;
1858     }
1859 }
1860
1861 static Object *object_resolve_abs_path(Object *parent,
1862                                           gchar **parts,
1863                                           const char *typename,
1864                                           int index)
1865 {
1866     Object *child;
1867
1868     if (parts[index] == NULL) {
1869         return object_dynamic_cast(parent, typename);
1870     }
1871
1872     if (strcmp(parts[index], "") == 0) {
1873         return object_resolve_abs_path(parent, parts, typename, index + 1);
1874     }
1875
1876     child = object_resolve_path_component(parent, parts[index]);
1877     if (!child) {
1878         return NULL;
1879     }
1880
1881     return object_resolve_abs_path(child, parts, typename, index + 1);
1882 }
1883
1884 static Object *object_resolve_partial_path(Object *parent,
1885                                               gchar **parts,
1886                                               const char *typename,
1887                                               bool *ambiguous)
1888 {
1889     Object *obj;
1890     GHashTableIter iter;
1891     ObjectProperty *prop;
1892
1893     obj = object_resolve_abs_path(parent, parts, typename, 0);
1894
1895     g_hash_table_iter_init(&iter, parent->properties);
1896     while (g_hash_table_iter_next(&iter, NULL, (gpointer *)&prop)) {
1897         Object *found;
1898
1899         if (!object_property_is_child(prop)) {
1900             continue;
1901         }
1902
1903         found = object_resolve_partial_path(prop->opaque, parts,
1904                                             typename, ambiguous);
1905         if (found) {
1906             if (obj) {
1907                 *ambiguous = true;
1908                 return NULL;
1909             }
1910             obj = found;
1911         }
1912
1913         if (*ambiguous) {
1914             return NULL;
1915         }
1916     }
1917
1918     return obj;
1919 }
1920
1921 Object *object_resolve_path_type(const char *path, const char *typename,
1922                                  bool *ambiguousp)
1923 {
1924     Object *obj;
1925     gchar **parts;
1926
1927     parts = g_strsplit(path, "/", 0);
1928     assert(parts);
1929
1930     if (parts[0] == NULL || strcmp(parts[0], "") != 0) {
1931         bool ambiguous = false;
1932         obj = object_resolve_partial_path(object_get_root(), parts,
1933                                           typename, &ambiguous);
1934         if (ambiguousp) {
1935             *ambiguousp = ambiguous;
1936         }
1937     } else {
1938         obj = object_resolve_abs_path(object_get_root(), parts, typename, 1);
1939     }
1940
1941     g_strfreev(parts);
1942
1943     return obj;
1944 }
1945
1946 Object *object_resolve_path(const char *path, bool *ambiguous)
1947 {
1948     return object_resolve_path_type(path, TYPE_OBJECT, ambiguous);
1949 }
1950
1951 typedef struct StringProperty
1952 {
1953     char *(*get)(Object *, Error **);
1954     void (*set)(Object *, const char *, Error **);
1955 } StringProperty;
1956
1957 static void property_get_str(Object *obj, Visitor *v, const char *name,
1958                              void *opaque, Error **errp)
1959 {
1960     StringProperty *prop = opaque;
1961     char *value;
1962     Error *err = NULL;
1963
1964     value = prop->get(obj, &err);
1965     if (err) {
1966         error_propagate(errp, err);
1967         return;
1968     }
1969
1970     visit_type_str(v, name, &value, errp);
1971     g_free(value);
1972 }
1973
1974 static void property_set_str(Object *obj, Visitor *v, const char *name,
1975                              void *opaque, Error **errp)
1976 {
1977     StringProperty *prop = opaque;
1978     char *value;
1979     Error *local_err = NULL;
1980
1981     visit_type_str(v, name, &value, &local_err);
1982     if (local_err) {
1983         error_propagate(errp, local_err);
1984         return;
1985     }
1986
1987     prop->set(obj, value, errp);
1988     g_free(value);
1989 }
1990
1991 static void property_release_str(Object *obj, const char *name,
1992                                  void *opaque)
1993 {
1994     StringProperty *prop = opaque;
1995     g_free(prop);
1996 }
1997
1998 void object_property_add_str(Object *obj, const char *name,
1999                            char *(*get)(Object *, Error **),
2000                            void (*set)(Object *, const char *, Error **),
2001                            Error **errp)
2002 {
2003     Error *local_err = NULL;
2004     StringProperty *prop = g_malloc0(sizeof(*prop));
2005
2006     prop->get = get;
2007     prop->set = set;
2008
2009     object_property_add(obj, name, "string",
2010                         get ? property_get_str : NULL,
2011                         set ? property_set_str : NULL,
2012                         property_release_str,
2013                         prop, &local_err);
2014     if (local_err) {
2015         error_propagate(errp, local_err);
2016         g_free(prop);
2017     }
2018 }
2019
2020 void object_class_property_add_str(ObjectClass *klass, const char *name,
2021                                    char *(*get)(Object *, Error **),
2022                                    void (*set)(Object *, const char *,
2023                                                Error **),
2024                                    Error **errp)
2025 {
2026     Error *local_err = NULL;
2027     StringProperty *prop = g_malloc0(sizeof(*prop));
2028
2029     prop->get = get;
2030     prop->set = set;
2031
2032     object_class_property_add(klass, name, "string",
2033                               get ? property_get_str : NULL,
2034                               set ? property_set_str : NULL,
2035                               property_release_str,
2036                               prop, &local_err);
2037     if (local_err) {
2038         error_propagate(errp, local_err);
2039         g_free(prop);
2040     }
2041 }
2042
2043 typedef struct BoolProperty
2044 {
2045     bool (*get)(Object *, Error **);
2046     void (*set)(Object *, bool, Error **);
2047 } BoolProperty;
2048
2049 static void property_get_bool(Object *obj, Visitor *v, const char *name,
2050                               void *opaque, Error **errp)
2051 {
2052     BoolProperty *prop = opaque;
2053     bool value;
2054     Error *err = NULL;
2055
2056     value = prop->get(obj, &err);
2057     if (err) {
2058         error_propagate(errp, err);
2059         return;
2060     }
2061
2062     visit_type_bool(v, name, &value, errp);
2063 }
2064
2065 static void property_set_bool(Object *obj, Visitor *v, const char *name,
2066                               void *opaque, Error **errp)
2067 {
2068     BoolProperty *prop = opaque;
2069     bool value;
2070     Error *local_err = NULL;
2071
2072     visit_type_bool(v, name, &value, &local_err);
2073     if (local_err) {
2074         error_propagate(errp, local_err);
2075         return;
2076     }
2077
2078     prop->set(obj, value, errp);
2079 }
2080
2081 static void property_release_bool(Object *obj, const char *name,
2082                                   void *opaque)
2083 {
2084     BoolProperty *prop = opaque;
2085     g_free(prop);
2086 }
2087
2088 void object_property_add_bool(Object *obj, const char *name,
2089                               bool (*get)(Object *, Error **),
2090                               void (*set)(Object *, bool, Error **),
2091                               Error **errp)
2092 {
2093     Error *local_err = NULL;
2094     BoolProperty *prop = g_malloc0(sizeof(*prop));
2095
2096     prop->get = get;
2097     prop->set = set;
2098
2099     object_property_add(obj, name, "bool",
2100                         get ? property_get_bool : NULL,
2101                         set ? property_set_bool : NULL,
2102                         property_release_bool,
2103                         prop, &local_err);
2104     if (local_err) {
2105         error_propagate(errp, local_err);
2106         g_free(prop);
2107     }
2108 }
2109
2110 void object_class_property_add_bool(ObjectClass *klass, const char *name,
2111                                     bool (*get)(Object *, Error **),
2112                                     void (*set)(Object *, bool, Error **),
2113                                     Error **errp)
2114 {
2115     Error *local_err = NULL;
2116     BoolProperty *prop = g_malloc0(sizeof(*prop));
2117
2118     prop->get = get;
2119     prop->set = set;
2120
2121     object_class_property_add(klass, name, "bool",
2122                               get ? property_get_bool : NULL,
2123                               set ? property_set_bool : NULL,
2124                               property_release_bool,
2125                               prop, &local_err);
2126     if (local_err) {
2127         error_propagate(errp, local_err);
2128         g_free(prop);
2129     }
2130 }
2131
2132 static void property_get_enum(Object *obj, Visitor *v, const char *name,
2133                               void *opaque, Error **errp)
2134 {
2135     EnumProperty *prop = opaque;
2136     int value;
2137     Error *err = NULL;
2138
2139     value = prop->get(obj, &err);
2140     if (err) {
2141         error_propagate(errp, err);
2142         return;
2143     }
2144
2145     visit_type_enum(v, name, &value, prop->lookup, errp);
2146 }
2147
2148 static void property_set_enum(Object *obj, Visitor *v, const char *name,
2149                               void *opaque, Error **errp)
2150 {
2151     EnumProperty *prop = opaque;
2152     int value;
2153     Error *err = NULL;
2154
2155     visit_type_enum(v, name, &value, prop->lookup, &err);
2156     if (err) {
2157         error_propagate(errp, err);
2158         return;
2159     }
2160     prop->set(obj, value, errp);
2161 }
2162
2163 static void property_release_enum(Object *obj, const char *name,
2164                                   void *opaque)
2165 {
2166     EnumProperty *prop = opaque;
2167     g_free(prop);
2168 }
2169
2170 void object_property_add_enum(Object *obj, const char *name,
2171                               const char *typename,
2172                               const QEnumLookup *lookup,
2173                               int (*get)(Object *, Error **),
2174                               void (*set)(Object *, int, Error **),
2175                               Error **errp)
2176 {
2177     Error *local_err = NULL;
2178     EnumProperty *prop = g_malloc(sizeof(*prop));
2179
2180     prop->lookup = lookup;
2181     prop->get = get;
2182     prop->set = set;
2183
2184     object_property_add(obj, name, typename,
2185                         get ? property_get_enum : NULL,
2186                         set ? property_set_enum : NULL,
2187                         property_release_enum,
2188                         prop, &local_err);
2189     if (local_err) {
2190         error_propagate(errp, local_err);
2191         g_free(prop);
2192     }
2193 }
2194
2195 void object_class_property_add_enum(ObjectClass *klass, const char *name,
2196                                     const char *typename,
2197                                     const QEnumLookup *lookup,
2198                                     int (*get)(Object *, Error **),
2199                                     void (*set)(Object *, int, Error **),
2200                                     Error **errp)
2201 {
2202     Error *local_err = NULL;
2203     EnumProperty *prop = g_malloc(sizeof(*prop));
2204
2205     prop->lookup = lookup;
2206     prop->get = get;
2207     prop->set = set;
2208
2209     object_class_property_add(klass, name, typename,
2210                               get ? property_get_enum : NULL,
2211                               set ? property_set_enum : NULL,
2212                               property_release_enum,
2213                               prop, &local_err);
2214     if (local_err) {
2215         error_propagate(errp, local_err);
2216         g_free(prop);
2217     }
2218 }
2219
2220 typedef struct TMProperty {
2221     void (*get)(Object *, struct tm *, Error **);
2222 } TMProperty;
2223
2224 static void property_get_tm(Object *obj, Visitor *v, const char *name,
2225                             void *opaque, Error **errp)
2226 {
2227     TMProperty *prop = opaque;
2228     Error *err = NULL;
2229     struct tm value;
2230
2231     prop->get(obj, &value, &err);
2232     if (err) {
2233         goto out;
2234     }
2235
2236     visit_start_struct(v, name, NULL, 0, &err);
2237     if (err) {
2238         goto out;
2239     }
2240     visit_type_int32(v, "tm_year", &value.tm_year, &err);
2241     if (err) {
2242         goto out_end;
2243     }
2244     visit_type_int32(v, "tm_mon", &value.tm_mon, &err);
2245     if (err) {
2246         goto out_end;
2247     }
2248     visit_type_int32(v, "tm_mday", &value.tm_mday, &err);
2249     if (err) {
2250         goto out_end;
2251     }
2252     visit_type_int32(v, "tm_hour", &value.tm_hour, &err);
2253     if (err) {
2254         goto out_end;
2255     }
2256     visit_type_int32(v, "tm_min", &value.tm_min, &err);
2257     if (err) {
2258         goto out_end;
2259     }
2260     visit_type_int32(v, "tm_sec", &value.tm_sec, &err);
2261     if (err) {
2262         goto out_end;
2263     }
2264     visit_check_struct(v, &err);
2265 out_end:
2266     visit_end_struct(v, NULL);
2267 out:
2268     error_propagate(errp, err);
2269
2270 }
2271
2272 static void property_release_tm(Object *obj, const char *name,
2273                                 void *opaque)
2274 {
2275     TMProperty *prop = opaque;
2276     g_free(prop);
2277 }
2278
2279 void object_property_add_tm(Object *obj, const char *name,
2280                             void (*get)(Object *, struct tm *, Error **),
2281                             Error **errp)
2282 {
2283     Error *local_err = NULL;
2284     TMProperty *prop = g_malloc0(sizeof(*prop));
2285
2286     prop->get = get;
2287
2288     object_property_add(obj, name, "struct tm",
2289                         get ? property_get_tm : NULL, NULL,
2290                         property_release_tm,
2291                         prop, &local_err);
2292     if (local_err) {
2293         error_propagate(errp, local_err);
2294         g_free(prop);
2295     }
2296 }
2297
2298 void object_class_property_add_tm(ObjectClass *klass, const char *name,
2299                                   void (*get)(Object *, struct tm *, Error **),
2300                                   Error **errp)
2301 {
2302     Error *local_err = NULL;
2303     TMProperty *prop = g_malloc0(sizeof(*prop));
2304
2305     prop->get = get;
2306
2307     object_class_property_add(klass, name, "struct tm",
2308                               get ? property_get_tm : NULL, NULL,
2309                               property_release_tm,
2310                               prop, &local_err);
2311     if (local_err) {
2312         error_propagate(errp, local_err);
2313         g_free(prop);
2314     }
2315 }
2316
2317 static char *qdev_get_type(Object *obj, Error **errp)
2318 {
2319     return g_strdup(object_get_typename(obj));
2320 }
2321
2322 static void property_get_uint8_ptr(Object *obj, Visitor *v, const char *name,
2323                                    void *opaque, Error **errp)
2324 {
2325     uint8_t value = *(uint8_t *)opaque;
2326     visit_type_uint8(v, name, &value, errp);
2327 }
2328
2329 static void property_get_uint16_ptr(Object *obj, Visitor *v, const char *name,
2330                                     void *opaque, Error **errp)
2331 {
2332     uint16_t value = *(uint16_t *)opaque;
2333     visit_type_uint16(v, name, &value, errp);
2334 }
2335
2336 static void property_get_uint32_ptr(Object *obj, Visitor *v, const char *name,
2337                                     void *opaque, Error **errp)
2338 {
2339     uint32_t value = *(uint32_t *)opaque;
2340     visit_type_uint32(v, name, &value, errp);
2341 }
2342
2343 static void property_get_uint64_ptr(Object *obj, Visitor *v, const char *name,
2344                                     void *opaque, Error **errp)
2345 {
2346     uint64_t value = *(uint64_t *)opaque;
2347     visit_type_uint64(v, name, &value, errp);
2348 }
2349
2350 void object_property_add_uint8_ptr(Object *obj, const char *name,
2351                                    const uint8_t *v, Error **errp)
2352 {
2353     object_property_add(obj, name, "uint8", property_get_uint8_ptr,
2354                         NULL, NULL, (void *)v, errp);
2355 }
2356
2357 void object_class_property_add_uint8_ptr(ObjectClass *klass, const char *name,
2358                                          const uint8_t *v, Error **errp)
2359 {
2360     object_class_property_add(klass, name, "uint8", property_get_uint8_ptr,
2361                               NULL, NULL, (void *)v, errp);
2362 }
2363
2364 void object_property_add_uint16_ptr(Object *obj, const char *name,
2365                                     const uint16_t *v, Error **errp)
2366 {
2367     object_property_add(obj, name, "uint16", property_get_uint16_ptr,
2368                         NULL, NULL, (void *)v, errp);
2369 }
2370
2371 void object_class_property_add_uint16_ptr(ObjectClass *klass, const char *name,
2372                                           const uint16_t *v, Error **errp)
2373 {
2374     object_class_property_add(klass, name, "uint16", property_get_uint16_ptr,
2375                               NULL, NULL, (void *)v, errp);
2376 }
2377
2378 void object_property_add_uint32_ptr(Object *obj, const char *name,
2379                                     const uint32_t *v, Error **errp)
2380 {
2381     object_property_add(obj, name, "uint32", property_get_uint32_ptr,
2382                         NULL, NULL, (void *)v, errp);
2383 }
2384
2385 void object_class_property_add_uint32_ptr(ObjectClass *klass, const char *name,
2386                                           const uint32_t *v, Error **errp)
2387 {
2388     object_class_property_add(klass, name, "uint32", property_get_uint32_ptr,
2389                               NULL, NULL, (void *)v, errp);
2390 }
2391
2392 void object_property_add_uint64_ptr(Object *obj, const char *name,
2393                                     const uint64_t *v, Error **errp)
2394 {
2395     object_property_add(obj, name, "uint64", property_get_uint64_ptr,
2396                         NULL, NULL, (void *)v, errp);
2397 }
2398
2399 void object_class_property_add_uint64_ptr(ObjectClass *klass, const char *name,
2400                                           const uint64_t *v, Error **errp)
2401 {
2402     object_class_property_add(klass, name, "uint64", property_get_uint64_ptr,
2403                               NULL, NULL, (void *)v, errp);
2404 }
2405
2406 typedef struct {
2407     Object *target_obj;
2408     char *target_name;
2409 } AliasProperty;
2410
2411 static void property_get_alias(Object *obj, Visitor *v, const char *name,
2412                                void *opaque, Error **errp)
2413 {
2414     AliasProperty *prop = opaque;
2415
2416     object_property_get(prop->target_obj, v, prop->target_name, errp);
2417 }
2418
2419 static void property_set_alias(Object *obj, Visitor *v, const char *name,
2420                                void *opaque, Error **errp)
2421 {
2422     AliasProperty *prop = opaque;
2423
2424     object_property_set(prop->target_obj, v, prop->target_name, errp);
2425 }
2426
2427 static Object *property_resolve_alias(Object *obj, void *opaque,
2428                                       const gchar *part)
2429 {
2430     AliasProperty *prop = opaque;
2431
2432     return object_resolve_path_component(prop->target_obj, prop->target_name);
2433 }
2434
2435 static void property_release_alias(Object *obj, const char *name, void *opaque)
2436 {
2437     AliasProperty *prop = opaque;
2438
2439     g_free(prop->target_name);
2440     g_free(prop);
2441 }
2442
2443 void object_property_add_alias(Object *obj, const char *name,
2444                                Object *target_obj, const char *target_name,
2445                                Error **errp)
2446 {
2447     AliasProperty *prop;
2448     ObjectProperty *op;
2449     ObjectProperty *target_prop;
2450     gchar *prop_type;
2451     Error *local_err = NULL;
2452
2453     target_prop = object_property_find(target_obj, target_name, errp);
2454     if (!target_prop) {
2455         return;
2456     }
2457
2458     if (object_property_is_child(target_prop)) {
2459         prop_type = g_strdup_printf("link%s",
2460                                     target_prop->type + strlen("child"));
2461     } else {
2462         prop_type = g_strdup(target_prop->type);
2463     }
2464
2465     prop = g_malloc(sizeof(*prop));
2466     prop->target_obj = target_obj;
2467     prop->target_name = g_strdup(target_name);
2468
2469     op = object_property_add(obj, name, prop_type,
2470                              property_get_alias,
2471                              property_set_alias,
2472                              property_release_alias,
2473                              prop, &local_err);
2474     if (local_err) {
2475         error_propagate(errp, local_err);
2476         g_free(prop);
2477         goto out;
2478     }
2479     op->resolve = property_resolve_alias;
2480
2481     object_property_set_description(obj, op->name,
2482                                     target_prop->description,
2483                                     &error_abort);
2484
2485 out:
2486     g_free(prop_type);
2487 }
2488
2489 void object_property_set_description(Object *obj, const char *name,
2490                                      const char *description, Error **errp)
2491 {
2492     ObjectProperty *op;
2493
2494     op = object_property_find(obj, name, errp);
2495     if (!op) {
2496         return;
2497     }
2498
2499     g_free(op->description);
2500     op->description = g_strdup(description);
2501 }
2502
2503 void object_class_property_set_description(ObjectClass *klass,
2504                                            const char *name,
2505                                            const char *description,
2506                                            Error **errp)
2507 {
2508     ObjectProperty *op;
2509
2510     op = g_hash_table_lookup(klass->properties, name);
2511     if (!op) {
2512         error_setg(errp, "Property '.%s' not found", name);
2513         return;
2514     }
2515
2516     g_free(op->description);
2517     op->description = g_strdup(description);
2518 }
2519
2520 static void object_class_init(ObjectClass *klass, void *data)
2521 {
2522     object_class_property_add_str(klass, "type", qdev_get_type,
2523                                   NULL, &error_abort);
2524 }
2525
2526 static void register_types(void)
2527 {
2528     static TypeInfo interface_info = {
2529         .name = TYPE_INTERFACE,
2530         .class_size = sizeof(InterfaceClass),
2531         .abstract = true,
2532     };
2533
2534     static TypeInfo object_info = {
2535         .name = TYPE_OBJECT,
2536         .instance_size = sizeof(Object),
2537         .class_init = object_class_init,
2538         .abstract = true,
2539     };
2540
2541     type_interface = type_register_internal(&interface_info);
2542     type_register_internal(&object_info);
2543 }
2544
2545 type_init(register_types)