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 "qom/object.h"
  14 #include "qemu-common.h"
  15 #include "qapi/visitor.h"
  16 #include "qapi/string-input-visitor.h"
  17 #include "qapi/string-output-visitor.h"
  18 #include "qapi/qmp/qerror.h"
  19 #include "trace.h"
  20
  21 /* TODO: replace QObject with a simpler visitor to avoid a dependency
  22  * of the QOM core on QObject?  */
  23 #include "qom/qom-qobject.h"
  24 #include "qapi/qmp/qobject.h"
  25 #include "qapi/qmp/qbool.h"
  26 #include "qapi/qmp/qint.h"
  27 #include "qapi/qmp/qstring.h"
  28
  29 #define MAX_INTERFACES 32
  30
  31 typedef struct InterfaceImpl InterfaceImpl;
  32 typedef struct TypeImpl TypeImpl;
  33
  34 struct InterfaceImpl
  35 {
  36     const char *typename;
  37 };
  38
  39 struct TypeImpl
  40 {
  41     const char *name;
  42
  43     size_t class_size;
  44
  45     size_t instance_size;
  46
  47     void (*class_init)(ObjectClass *klass, void *data);
  48     void (*class_base_init)(ObjectClass *klass, void *data);
  49     void (*class_finalize)(ObjectClass *klass, void *data);
  50
  51     void *class_data;
  52
  53     void (*instance_init)(Object *obj);
  54     void (*instance_finalize)(Object *obj);
  55
  56     bool abstract;
  57
  58     const char *parent;
  59     TypeImpl *parent_type;
  60
  61     ObjectClass *class;
  62
  63     int num_interfaces;
  64     InterfaceImpl interfaces[MAX_INTERFACES];
  65 };
  66
  67 static Type type_interface;
  68
  69 static GHashTable *type_table_get(void)
  70 {
  71     static GHashTable *type_table;
  72
  73     if (type_table == NULL) {
  74         type_table = g_hash_table_new(g_str_hash, g_str_equal);
  75     }
  76
  77     return type_table;
  78 }
  79
  80 static void type_table_add(TypeImpl *ti)
  81 {
  82     g_hash_table_insert(type_table_get(), (void *)ti->name, ti);
  83 }
  84
  85 static TypeImpl *type_table_lookup(const char *name)
  86 {
  87     return g_hash_table_lookup(type_table_get(), name);
  88 }
  89
  90 static TypeImpl *type_register_internal(const TypeInfo *info)
  91 {
  92     TypeImpl *ti = g_malloc0(sizeof(*ti));
  93     int i;
  94
  95     g_assert(info->name != NULL);
  96
  97     if (type_table_lookup(info->name) != NULL) {
  98         fprintf(stderr, "Registering `%s' which already exists\n", info->name);
  99         abort();
 100     }
 101
 102     ti->name = g_strdup(info->name);
 103     ti->parent = g_strdup(info->parent);
 104
 105     ti->class_size = info->class_size;
 106     ti->instance_size = info->instance_size;
 107
 108     ti->class_init = info->class_init;
 109     ti->class_base_init = info->class_base_init;
 110     ti->class_finalize = info->class_finalize;
 111     ti->class_data = info->class_data;
 112
 113     ti->instance_init = info->instance_init;
 114     ti->instance_finalize = info->instance_finalize;
 115
 116     ti->abstract = info->abstract;
 117
 118     for (i = 0; info->interfaces && info->interfaces[i].type; i++) {
 119         ti->interfaces[i].typename = g_strdup(info->interfaces[i].type);
 120     }
 121     ti->num_interfaces = i;
 122
 123     type_table_add(ti);
 124
 125     return ti;
 126 }
 127
 128 TypeImpl *type_register(const TypeInfo *info)
 129 {
 130     assert(info->parent);
 131     return type_register_internal(info);
 132 }
 133
 134 TypeImpl *type_register_static(const TypeInfo *info)
 135 {
 136     return type_register(info);
 137 }
 138
 139 static TypeImpl *type_get_by_name(const char *name)
 140 {
 141     if (name == NULL) {
 142         return NULL;
 143     }
 144
 145     return type_table_lookup(name);
 146 }
 147
 148 static TypeImpl *type_get_parent(TypeImpl *type)
 149 {
 150     if (!type->parent_type && type->parent) {
 151         type->parent_type = type_get_by_name(type->parent);
 152         g_assert(type->parent_type != NULL);
 153     }
 154
 155     return type->parent_type;
 156 }
 157
 158 static bool type_has_parent(TypeImpl *type)
 159 {
 160     return (type->parent != NULL);
 161 }
 162
 163 static size_t type_class_get_size(TypeImpl *ti)
 164 {
 165     if (ti->class_size) {
 166         return ti->class_size;
 167     }
 168
 169     if (type_has_parent(ti)) {
 170         return type_class_get_size(type_get_parent(ti));
 171     }
 172
 173     return sizeof(ObjectClass);
 174 }
 175
 176 static size_t type_object_get_size(TypeImpl *ti)
 177 {
 178     if (ti->instance_size) {
 179         return ti->instance_size;
 180     }
 181
 182     if (type_has_parent(ti)) {
 183         return type_object_get_size(type_get_parent(ti));
 184     }
 185
 186     return 0;
 187 }
 188
 189 static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
 190 {
 191     assert(target_type);
 192
 193     /* Check if typename is a direct ancestor of type */
 194     while (type) {
 195         if (type == target_type) {
 196             return true;
 197         }
 198
 199         type = type_get_parent(type);
 200     }
 201
 202     return false;
 203 }
 204
 205 static void type_initialize(TypeImpl *ti);
 206
 207 static void type_initialize_interface(TypeImpl *ti, const char *parent)
 208 {
 209     InterfaceClass *new_iface;
 210     TypeInfo info = { };
 211     TypeImpl *iface_impl;
 212
 213     info.parent = parent;
 214     info.name = g_strdup_printf("%s::%s", ti->name, info.parent);
 215     info.abstract = true;
 216
 217     iface_impl = type_register(&info);
 218     type_initialize(iface_impl);
 219     g_free((char *)info.name);
 220
 221     new_iface = (InterfaceClass *)iface_impl->class;
 222     new_iface->concrete_class = ti->class;
 223
 224     ti->class->interfaces = g_slist_append(ti->class->interfaces,
 225                                            iface_impl->class);
 226 }
 227
 228 static void type_initialize(TypeImpl *ti)
 229 {
 230     TypeImpl *parent;
 231
 232     if (ti->class) {
 233         return;
 234     }
 235
 236     ti->class_size = type_class_get_size(ti);
 237     ti->instance_size = type_object_get_size(ti);
 238
 239     ti->class = g_malloc0(ti->class_size);
 240
 241     parent = type_get_parent(ti);
 242     if (parent) {
 243         type_initialize(parent);
 244         GSList *e;
 245         int i;
 246
 247         g_assert(parent->class_size <= ti->class_size);
 248         memcpy(ti->class, parent->class, parent->class_size);
 249         ti->class->interfaces = NULL;
 250
 251         for (e = parent->class->interfaces; e; e = e->next) {
 252             ObjectClass *iface = e->data;
 253             type_initialize_interface(ti, object_class_get_name(iface));
 254         }
 255
 256         for (i = 0; i < ti->num_interfaces; i++) {
 257             TypeImpl *t = type_get_by_name(ti->interfaces[i].typename);
 258             for (e = ti->class->interfaces; e; e = e->next) {
 259                 TypeImpl *target_type = OBJECT_CLASS(e->data)->type;
 260
 261                 if (type_is_ancestor(target_type, t)) {
 262                     break;
 263                 }
 264             }
 265
 266             if (e) {
 267                 continue;
 268             }
 269
 270             type_initialize_interface(ti, ti->interfaces[i].typename);
 271         }
 272     }
 273
 274     ti->class->type = ti;
 275
 276     while (parent) {
 277         if (parent->class_base_init) {
 278             parent->class_base_init(ti->class, ti->class_data);
 279         }
 280         parent = type_get_parent(parent);
 281     }
 282
 283     if (ti->class_init) {
 284         ti->class_init(ti->class, ti->class_data);
 285     }
 286
 287
 288 }
 289
 290 static void object_init_with_type(Object *obj, TypeImpl *ti)
 291 {
 292     if (type_has_parent(ti)) {
 293         object_init_with_type(obj, type_get_parent(ti));
 294     }
 295
 296     if (ti->instance_init) {
 297         ti->instance_init(obj);
 298     }
 299 }
 300
 301 void object_initialize_with_type(void *data, TypeImpl *type)
 302 {
 303     Object *obj = data;
 304
 305     g_assert(type != NULL);
 306     type_initialize(type);
 307
 308     g_assert(type->instance_size >= sizeof(Object));
 309     g_assert(type->abstract == false);
 310
 311     memset(obj, 0, type->instance_size);
 312     obj->class = type->class;
 313     object_ref(obj);
 314     QTAILQ_INIT(&obj->properties);
 315     object_init_with_type(obj, type);
 316 }
 317
 318 void object_initialize(void *data, const char *typename)
 319 {
 320     TypeImpl *type = type_get_by_name(typename);
 321
 322     object_initialize_with_type(data, type);
 323 }
 324
 325 static inline bool object_property_is_child(ObjectProperty *prop)
 326 {
 327     return strstart(prop->type, "child<", NULL);
 328 }
 329
 330 static inline bool object_property_is_link(ObjectProperty *prop)
 331 {
 332     return strstart(prop->type, "link<", NULL);
 333 }
 334
 335 static void object_property_del_all(Object *obj)
 336 {
 337     while (!QTAILQ_EMPTY(&obj->properties)) {
 338         ObjectProperty *prop = QTAILQ_FIRST(&obj->properties);
 339
 340         QTAILQ_REMOVE(&obj->properties, prop, node);
 341
 342         if (prop->release) {
 343             prop->release(obj, prop->name, prop->opaque);
 344         }
 345
 346         g_free(prop->name);
 347         g_free(prop->type);
 348         g_free(prop);
 349     }
 350 }
 351
 352 static void object_property_del_child(Object *obj, Object *child, Error **errp)
 353 {
 354     ObjectProperty *prop;
 355
 356     QTAILQ_FOREACH(prop, &obj->properties, node) {
 357         if (object_property_is_child(prop) && prop->opaque == child) {
 358             object_property_del(obj, prop->name, errp);
 359             break;
 360         }
 361     }
 362 }
 363
 364 void object_unparent(Object *obj)
 365 {
 366     if (!obj->parent) {
 367         return;
 368     }
 369
 370     object_ref(obj);
 371     if (obj->class->unparent) {
 372         (obj->class->unparent)(obj);
 373     }
 374     if (obj->parent) {
 375         object_property_del_child(obj->parent, obj, NULL);
 376     }
 377     object_unref(obj);
 378 }
 379
 380 static void object_deinit(Object *obj, TypeImpl *type)
 381 {
 382     if (type->instance_finalize) {
 383         type->instance_finalize(obj);
 384     }
 385
 386     if (type_has_parent(type)) {
 387         object_deinit(obj, type_get_parent(type));
 388     }
 389 }
 390
 391 static void object_finalize(void *data)
 392 {
 393     Object *obj = data;
 394     TypeImpl *ti = obj->class->type;
 395
 396     object_deinit(obj, ti);
 397     object_property_del_all(obj);
 398
 399     g_assert(obj->ref == 0);
 400     if (obj->free) {
 401         obj->free(obj);
 402     }
 403 }
 404
 405 Object *object_new_with_type(Type type)
 406 {
 407     Object *obj;
 408
 409     g_assert(type != NULL);
 410     type_initialize(type);
 411
 412     obj = g_malloc(type->instance_size);
 413     object_initialize_with_type(obj, type);
 414     obj->free = g_free;
 415
 416     return obj;
 417 }
 418
 419 Object *object_new(const char *typename)
 420 {
 421     TypeImpl *ti = type_get_by_name(typename);
 422
 423     return object_new_with_type(ti);
 424 }
 425
 426 Object *object_dynamic_cast(Object *obj, const char *typename)
 427 {
 428     if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
 429         return obj;
 430     }
 431
 432     return NULL;
 433 }
 434
 435 Object *object_dynamic_cast_assert(Object *obj, const char *typename,
 436                                    const char *file, int line, const char *func)
 437 {
 438     trace_object_dynamic_cast_assert(obj ? obj->class->type->name : "(null)",
 439                                      typename, file, line, func);
 440
 441 #ifdef CONFIG_QOM_CAST_DEBUG
 442     int i;
 443     Object *inst;
 444
 445     for (i = 0; obj && i < OBJECT_CLASS_CAST_CACHE; i++) {
 446         if (obj->class->cast_cache[i] == typename) {
 447             goto out;
 448         }
 449     }
 450
 451     inst = object_dynamic_cast(obj, typename);
 452
 453     if (!inst && obj) {
 454         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
 455                 file, line, func, obj, typename);
 456         abort();
 457     }
 458
 459     assert(obj == inst);
 460
 461     if (obj && obj == inst) {
 462         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
 463             obj->class->cast_cache[i - 1] = obj->class->cast_cache[i];
 464         }
 465         obj->class->cast_cache[i - 1] = typename;
 466     }
 467
 468 out:
 469 #endif
 470     return obj;
 471 }
 472
 473 ObjectClass *object_class_dynamic_cast(ObjectClass *class,
 474                                        const char *typename)
 475 {
 476     ObjectClass *ret = NULL;
 477     TypeImpl *target_type;
 478     TypeImpl *type;
 479
 480     if (!class) {
 481         return NULL;
 482     }
 483
 484     /* A simple fast path that can trigger a lot for leaf classes.  */
 485     type = class->type;
 486     if (type->name == typename) {
 487         return class;
 488     }
 489
 490     target_type = type_get_by_name(typename);
 491     if (!target_type) {
 492         /* target class type unknown, so fail the cast */
 493         return NULL;
 494     }
 495
 496     if (type->class->interfaces &&
 497             type_is_ancestor(target_type, type_interface)) {
 498         int found = 0;
 499         GSList *i;
 500
 501         for (i = class->interfaces; i; i = i->next) {
 502             ObjectClass *target_class = i->data;
 503
 504             if (type_is_ancestor(target_class->type, target_type)) {
 505                 ret = target_class;
 506                 found++;
 507             }
 508          }
 509
 510         /* The match was ambiguous, don't allow a cast */
 511         if (found > 1) {
 512             ret = NULL;
 513         }
 514     } else if (type_is_ancestor(type, target_type)) {
 515         ret = class;
 516     }
 517
 518     return ret;
 519 }
 520
 521 ObjectClass *object_class_dynamic_cast_assert(ObjectClass *class,
 522                                               const char *typename,
 523                                               const char *file, int line,
 524                                               const char *func)
 525 {
 526     ObjectClass *ret;
 527
 528     trace_object_class_dynamic_cast_assert(class ? class->type->name : "(null)",
 529                                            typename, file, line, func);
 530
 531 #ifdef CONFIG_QOM_CAST_DEBUG
 532     int i;
 533
 534     for (i = 0; i < OBJECT_CLASS_CAST_CACHE; i++) {
 535         if (class->cast_cache[i] == typename) {
 536             ret = class;
 537             goto out;
 538         }
 539     }
 540 #else
 541     if (!class->interfaces) {
 542         return class;
 543     }
 544 #endif
 545
 546     ret = object_class_dynamic_cast(class, typename);
 547     if (!ret && class) {
 548         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
 549                 file, line, func, class, typename);
 550         abort();
 551     }
 552
 553 #ifdef CONFIG_QOM_CAST_DEBUG
 554     if (ret == class) {
 555         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
 556             class->cast_cache[i - 1] = class->cast_cache[i];
 557         }
 558         class->cast_cache[i - 1] = typename;
 559     }
 560 out:
 561 #endif
 562     return ret;
 563 }
 564
 565 const char *object_get_typename(Object *obj)
 566 {
 567     return obj->class->type->name;
 568 }
 569
 570 ObjectClass *object_get_class(Object *obj)
 571 {
 572     return obj->class;
 573 }
 574
 575 bool object_class_is_abstract(ObjectClass *klass)
 576 {
 577     return klass->type->abstract;
 578 }
 579
 580 const char *object_class_get_name(ObjectClass *klass)
 581 {
 582     return klass->type->name;
 583 }
 584
 585 ObjectClass *object_class_by_name(const char *typename)
 586 {
 587     TypeImpl *type = type_get_by_name(typename);
 588
 589     if (!type) {
 590         return NULL;
 591     }
 592
 593     type_initialize(type);
 594
 595     return type->class;
 596 }
 597
 598 ObjectClass *object_class_get_parent(ObjectClass *class)
 599 {
 600     TypeImpl *type = type_get_parent(class->type);
 601
 602     if (!type) {
 603         return NULL;
 604     }
 605
 606     type_initialize(type);
 607
 608     return type->class;
 609 }
 610
 611 typedef struct OCFData
 612 {
 613     void (*fn)(ObjectClass *klass, void *opaque);
 614     const char *implements_type;
 615     bool include_abstract;
 616     void *opaque;
 617 } OCFData;
 618
 619 static void object_class_foreach_tramp(gpointer key, gpointer value,
 620                                        gpointer opaque)
 621 {
 622     OCFData *data = opaque;
 623     TypeImpl *type = value;
 624     ObjectClass *k;
 625
 626     type_initialize(type);
 627     k = type->class;
 628
 629     if (!data->include_abstract && type->abstract) {
 630         return;
 631     }
 632
 633     if (data->implements_type &&
 634         !object_class_dynamic_cast(k, data->implements_type)) {
 635         return;
 636     }
 637
 638     data->fn(k, data->opaque);
 639 }
 640
 641 void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
 642                           const char *implements_type, bool include_abstract,
 643                           void *opaque)
 644 {
 645     OCFData data = { fn, implements_type, include_abstract, opaque };
 646
 647     g_hash_table_foreach(type_table_get(), object_class_foreach_tramp, &data);
 648 }
 649
 650 int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
 651                          void *opaque)
 652 {
 653     ObjectProperty *prop;
 654     int ret = 0;
 655
 656     QTAILQ_FOREACH(prop, &obj->properties, node) {
 657         if (object_property_is_child(prop)) {
 658             ret = fn(prop->opaque, opaque);
 659             if (ret != 0) {
 660                 break;
 661             }
 662         }
 663     }
 664     return ret;
 665 }
 666
 667 static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
 668 {
 669     GSList **list = opaque;
 670
 671     *list = g_slist_prepend(*list, klass);
 672 }
 673
 674 GSList *object_class_get_list(const char *implements_type,
 675                               bool include_abstract)
 676 {
 677     GSList *list = NULL;
 678
 679     object_class_foreach(object_class_get_list_tramp,
 680                          implements_type, include_abstract, &list);
 681     return list;
 682 }
 683
 684 void object_ref(Object *obj)
 685 {
 686     obj->ref++;
 687 }
 688
 689 void object_unref(Object *obj)
 690 {
 691     g_assert(obj->ref > 0);
 692     obj->ref--;
 693
 694     /* parent always holds a reference to its children */
 695     if (obj->ref == 0) {
 696         object_finalize(obj);
 697     }
 698 }
 699
 700 void object_property_add(Object *obj, const char *name, const char *type,
 701                          ObjectPropertyAccessor *get,
 702                          ObjectPropertyAccessor *set,
 703                          ObjectPropertyRelease *release,
 704                          void *opaque, Error **errp)
 705 {
 706     ObjectProperty *prop;
 707
 708     QTAILQ_FOREACH(prop, &obj->properties, node) {
 709         if (strcmp(prop->name, name) == 0) {
 710             error_setg(errp, "attempt to add duplicate property '%s'"
 711                        " to object (type '%s')", name,
 712                        object_get_typename(obj));
 713             return;
 714         }
 715     }
 716
 717     prop = g_malloc0(sizeof(*prop));
 718
 719     prop->name = g_strdup(name);
 720     prop->type = g_strdup(type);
 721
 722     prop->get = get;
 723     prop->set = set;
 724     prop->release = release;
 725     prop->opaque = opaque;
 726
 727     QTAILQ_INSERT_TAIL(&obj->properties, prop, node);
 728 }
 729
 730 ObjectProperty *object_property_find(Object *obj, const char *name,
 731                                      Error **errp)
 732 {
 733     ObjectProperty *prop;
 734
 735     QTAILQ_FOREACH(prop, &obj->properties, node) {
 736         if (strcmp(prop->name, name) == 0) {
 737             return prop;
 738         }
 739     }
 740
 741     error_set(errp, QERR_PROPERTY_NOT_FOUND, "", name);
 742     return NULL;
 743 }
 744
 745 void object_property_del(Object *obj, const char *name, Error **errp)
 746 {
 747     ObjectProperty *prop = object_property_find(obj, name, errp);
 748     if (prop == NULL) {
 749         return;
 750     }
 751
 752     if (prop->release) {
 753         prop->release(obj, name, prop->opaque);
 754     }
 755
 756     QTAILQ_REMOVE(&obj->properties, prop, node);
 757
 758     g_free(prop->name);
 759     g_free(prop->type);
 760     g_free(prop);
 761 }
 762
 763 void object_property_get(Object *obj, Visitor *v, const char *name,
 764                          Error **errp)
 765 {
 766     ObjectProperty *prop = object_property_find(obj, name, errp);
 767     if (prop == NULL) {
 768         return;
 769     }
 770
 771     if (!prop->get) {
 772         error_set(errp, QERR_PERMISSION_DENIED);
 773     } else {
 774         prop->get(obj, v, prop->opaque, name, errp);
 775     }
 776 }
 777
 778 void object_property_set(Object *obj, Visitor *v, const char *name,
 779                          Error **errp)
 780 {
 781     ObjectProperty *prop = object_property_find(obj, name, errp);
 782     if (prop == NULL) {
 783         return;
 784     }
 785
 786     if (!prop->set) {
 787         error_set(errp, QERR_PERMISSION_DENIED);
 788     } else {
 789         prop->set(obj, v, prop->opaque, name, errp);
 790     }
 791 }
 792
 793 void object_property_set_str(Object *obj, const char *value,
 794                              const char *name, Error **errp)
 795 {
 796     QString *qstr = qstring_from_str(value);
 797     object_property_set_qobject(obj, QOBJECT(qstr), name, errp);
 798
 799     QDECREF(qstr);
 800 }
 801
 802 char *object_property_get_str(Object *obj, const char *name,
 803                               Error **errp)
 804 {
 805     QObject *ret = object_property_get_qobject(obj, name, errp);
 806     QString *qstring;
 807     char *retval;
 808
 809     if (!ret) {
 810         return NULL;
 811     }
 812     qstring = qobject_to_qstring(ret);
 813     if (!qstring) {
 814         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "string");
 815         retval = NULL;
 816     } else {
 817         retval = g_strdup(qstring_get_str(qstring));
 818     }
 819
 820     QDECREF(qstring);
 821     return retval;
 822 }
 823
 824 void object_property_set_link(Object *obj, Object *value,
 825                               const char *name, Error **errp)
 826 {
 827     object_property_set_str(obj, object_get_canonical_path(value),
 828                             name, errp);
 829 }
 830
 831 Object *object_property_get_link(Object *obj, const char *name,
 832                                  Error **errp)
 833 {
 834     char *str = object_property_get_str(obj, name, errp);
 835     Object *target = NULL;
 836
 837     if (str && *str) {
 838         target = object_resolve_path(str, NULL);
 839         if (!target) {
 840             error_set(errp, QERR_DEVICE_NOT_FOUND, str);
 841         }
 842     }
 843
 844     g_free(str);
 845     return target;
 846 }
 847
 848 void object_property_set_bool(Object *obj, bool value,
 849                               const char *name, Error **errp)
 850 {
 851     QBool *qbool = qbool_from_int(value);
 852     object_property_set_qobject(obj, QOBJECT(qbool), name, errp);
 853
 854     QDECREF(qbool);
 855 }
 856
 857 bool object_property_get_bool(Object *obj, const char *name,
 858                               Error **errp)
 859 {
 860     QObject *ret = object_property_get_qobject(obj, name, errp);
 861     QBool *qbool;
 862     bool retval;
 863
 864     if (!ret) {
 865         return false;
 866     }
 867     qbool = qobject_to_qbool(ret);
 868     if (!qbool) {
 869         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "boolean");
 870         retval = false;
 871     } else {
 872         retval = qbool_get_int(qbool);
 873     }
 874
 875     QDECREF(qbool);
 876     return retval;
 877 }
 878
 879 void object_property_set_int(Object *obj, int64_t value,
 880                              const char *name, Error **errp)
 881 {
 882     QInt *qint = qint_from_int(value);
 883     object_property_set_qobject(obj, QOBJECT(qint), name, errp);
 884
 885     QDECREF(qint);
 886 }
 887
 888 int64_t object_property_get_int(Object *obj, const char *name,
 889                                 Error **errp)
 890 {
 891     QObject *ret = object_property_get_qobject(obj, name, errp);
 892     QInt *qint;
 893     int64_t retval;
 894
 895     if (!ret) {
 896         return -1;
 897     }
 898     qint = qobject_to_qint(ret);
 899     if (!qint) {
 900         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "int");
 901         retval = -1;
 902     } else {
 903         retval = qint_get_int(qint);
 904     }
 905
 906     QDECREF(qint);
 907     return retval;
 908 }
 909
 910 void object_property_parse(Object *obj, const char *string,
 911                            const char *name, Error **errp)
 912 {
 913     StringInputVisitor *mi;
 914     mi = string_input_visitor_new(string);
 915     object_property_set(obj, string_input_get_visitor(mi), name, errp);
 916
 917     string_input_visitor_cleanup(mi);
 918 }
 919
 920 char *object_property_print(Object *obj, const char *name,
 921                             Error **errp)
 922 {
 923     StringOutputVisitor *mo;
 924     char *string;
 925
 926     mo = string_output_visitor_new();
 927     object_property_get(obj, string_output_get_visitor(mo), name, errp);
 928     string = string_output_get_string(mo);
 929     string_output_visitor_cleanup(mo);
 930     return string;
 931 }
 932
 933 const char *object_property_get_type(Object *obj, const char *name, Error **errp)
 934 {
 935     ObjectProperty *prop = object_property_find(obj, name, errp);
 936     if (prop == NULL) {
 937         return NULL;
 938     }
 939
 940     return prop->type;
 941 }
 942
 943 Object *object_get_root(void)
 944 {
 945     static Object *root;
 946
 947     if (!root) {
 948         root = object_new("container");
 949     }
 950
 951     return root;
 952 }
 953
 954 static void object_get_child_property(Object *obj, Visitor *v, void *opaque,
 955                                       const char *name, Error **errp)
 956 {
 957     Object *child = opaque;
 958     gchar *path;
 959
 960     path = object_get_canonical_path(child);
 961     visit_type_str(v, &path, name, errp);
 962     g_free(path);
 963 }
 964
 965 static void object_finalize_child_property(Object *obj, const char *name,
 966                                            void *opaque)
 967 {
 968     Object *child = opaque;
 969
 970     object_unref(child);
 971 }
 972
 973 void object_property_add_child(Object *obj, const char *name,
 974                                Object *child, Error **errp)
 975 {
 976     gchar *type;
 977
 978     type = g_strdup_printf("child<%s>", object_get_typename(OBJECT(child)));
 979
 980     object_property_add(obj, name, type, object_get_child_property,
 981                         NULL, object_finalize_child_property, child, errp);
 982
 983     object_ref(child);
 984     g_assert(child->parent == NULL);
 985     child->parent = obj;
 986
 987     g_free(type);
 988 }
 989
 990 static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
 991                                      const char *name, Error **errp)
 992 {
 993     Object **child = opaque;
 994     gchar *path;
 995
 996     if (*child) {
 997         path = object_get_canonical_path(*child);
 998         visit_type_str(v, &path, name, errp);
 999         g_free(path);
1000     } else {
1001         path = (gchar *)"";
1002         visit_type_str(v, &path, name, errp);
1003     }
1004 }
1005
1006 static void object_set_link_property(Object *obj, Visitor *v, void *opaque,
1007                                      const char *name, Error **errp)
1008 {
1009     Object **child = opaque;
1010     Object *old_target;
1011     bool ambiguous = false;
1012     const char *type;
1013     char *path;
1014     gchar *target_type;
1015
1016     type = object_property_get_type(obj, name, NULL);
1017
1018     visit_type_str(v, &path, name, errp);
1019
1020     old_target = *child;
1021     *child = NULL;
1022
1023     if (strcmp(path, "") != 0) {
1024         Object *target;
1025
1026         /* Go from link<FOO> to FOO.  */
1027         target_type = g_strndup(&type[5], strlen(type) - 6);
1028         target = object_resolve_path_type(path, target_type, &ambiguous);
1029
1030         if (ambiguous) {
1031             error_set(errp, QERR_AMBIGUOUS_PATH, path);
1032         } else if (target) {
1033             object_ref(target);
1034             *child = target;
1035         } else {
1036             target = object_resolve_path(path, &ambiguous);
1037             if (target || ambiguous) {
1038                 error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
1039             } else {
1040                 error_set(errp, QERR_DEVICE_NOT_FOUND, path);
1041             }
1042         }
1043         g_free(target_type);
1044     }
1045
1046     g_free(path);
1047
1048     if (old_target != NULL) {
1049         object_unref(old_target);
1050     }
1051 }
1052
1053 void object_property_add_link(Object *obj, const char *name,
1054                               const char *type, Object **child,
1055                               Error **errp)
1056 {
1057     gchar *full_type;
1058
1059     full_type = g_strdup_printf("link<%s>", type);
1060
1061     object_property_add(obj, name, full_type,
1062                         object_get_link_property,
1063                         object_set_link_property,
1064                         NULL, child, errp);
1065
1066     g_free(full_type);
1067 }
1068
1069 gchar *object_get_canonical_path(Object *obj)
1070 {
1071     Object *root = object_get_root();
1072     char *newpath = NULL, *path = NULL;
1073
1074     while (obj != root) {
1075         ObjectProperty *prop = NULL;
1076
1077         g_assert(obj->parent != NULL);
1078
1079         QTAILQ_FOREACH(prop, &obj->parent->properties, node) {
1080             if (!object_property_is_child(prop)) {
1081                 continue;
1082             }
1083
1084             if (prop->opaque == obj) {
1085                 if (path) {
1086                     newpath = g_strdup_printf("%s/%s", prop->name, path);
1087                     g_free(path);
1088                     path = newpath;
1089                 } else {
1090                     path = g_strdup(prop->name);
1091                 }
1092                 break;
1093             }
1094         }
1095
1096         g_assert(prop != NULL);
1097
1098         obj = obj->parent;
1099     }
1100
1101     newpath = g_strdup_printf("/%s", path);
1102     g_free(path);
1103
1104     return newpath;
1105 }
1106
1107 Object *object_resolve_path_component(Object *parent, const gchar *part)
1108 {
1109     ObjectProperty *prop = object_property_find(parent, part, NULL);
1110     if (prop == NULL) {
1111         return NULL;
1112     }
1113
1114     if (object_property_is_link(prop)) {
1115         return *(Object **)prop->opaque;
1116     } else if (object_property_is_child(prop)) {
1117         return prop->opaque;
1118     } else {
1119         return NULL;
1120     }
1121 }
1122
1123 static Object *object_resolve_abs_path(Object *parent,
1124                                           gchar **parts,
1125                                           const char *typename,
1126                                           int index)
1127 {
1128     Object *child;
1129
1130     if (parts[index] == NULL) {
1131         return object_dynamic_cast(parent, typename);
1132     }
1133
1134     if (strcmp(parts[index], "") == 0) {
1135         return object_resolve_abs_path(parent, parts, typename, index + 1);
1136     }
1137
1138     child = object_resolve_path_component(parent, parts[index]);
1139     if (!child) {
1140         return NULL;
1141     }
1142
1143     return object_resolve_abs_path(child, parts, typename, index + 1);
1144 }
1145
1146 static Object *object_resolve_partial_path(Object *parent,
1147                                               gchar **parts,
1148                                               const char *typename,
1149                                               bool *ambiguous)
1150 {
1151     Object *obj;
1152     ObjectProperty *prop;
1153
1154     obj = object_resolve_abs_path(parent, parts, typename, 0);
1155
1156     QTAILQ_FOREACH(prop, &parent->properties, node) {
1157         Object *found;
1158
1159         if (!object_property_is_child(prop)) {
1160             continue;
1161         }
1162
1163         found = object_resolve_partial_path(prop->opaque, parts,
1164                                             typename, ambiguous);
1165         if (found) {
1166             if (obj) {
1167                 if (ambiguous) {
1168                     *ambiguous = true;
1169                 }
1170                 return NULL;
1171             }
1172             obj = found;
1173         }
1174
1175         if (ambiguous && *ambiguous) {
1176             return NULL;
1177         }
1178     }
1179
1180     return obj;
1181 }
1182
1183 Object *object_resolve_path_type(const char *path, const char *typename,
1184                                  bool *ambiguous)
1185 {
1186     Object *obj;
1187     gchar **parts;
1188
1189     parts = g_strsplit(path, "/", 0);
1190     assert(parts);
1191
1192     if (parts[0] == NULL || strcmp(parts[0], "") != 0) {
1193         if (ambiguous) {
1194             *ambiguous = false;
1195         }
1196         obj = object_resolve_partial_path(object_get_root(), parts,
1197                                           typename, ambiguous);
1198     } else {
1199         obj = object_resolve_abs_path(object_get_root(), parts, typename, 1);
1200     }
1201
1202     g_strfreev(parts);
1203
1204     return obj;
1205 }
1206
1207 Object *object_resolve_path(const char *path, bool *ambiguous)
1208 {
1209     return object_resolve_path_type(path, TYPE_OBJECT, ambiguous);
1210 }
1211
1212 typedef struct StringProperty
1213 {
1214     char *(*get)(Object *, Error **);
1215     void (*set)(Object *, const char *, Error **);
1216 } StringProperty;
1217
1218 static void property_get_str(Object *obj, Visitor *v, void *opaque,
1219                              const char *name, Error **errp)
1220 {
1221     StringProperty *prop = opaque;
1222     char *value;
1223
1224     value = prop->get(obj, errp);
1225     if (value) {
1226         visit_type_str(v, &value, name, errp);
1227         g_free(value);
1228     }
1229 }
1230
1231 static void property_set_str(Object *obj, Visitor *v, void *opaque,
1232                              const char *name, Error **errp)
1233 {
1234     StringProperty *prop = opaque;
1235     char *value;
1236     Error *local_err = NULL;
1237
1238     visit_type_str(v, &value, name, &local_err);
1239     if (local_err) {
1240         error_propagate(errp, local_err);
1241         return;
1242     }
1243
1244     prop->set(obj, value, errp);
1245     g_free(value);
1246 }
1247
1248 static void property_release_str(Object *obj, const char *name,
1249                                  void *opaque)
1250 {
1251     StringProperty *prop = opaque;
1252     g_free(prop);
1253 }
1254
1255 void object_property_add_str(Object *obj, const char *name,
1256                            char *(*get)(Object *, Error **),
1257                            void (*set)(Object *, const char *, Error **),
1258                            Error **errp)
1259 {
1260     StringProperty *prop = g_malloc0(sizeof(*prop));
1261
1262     prop->get = get;
1263     prop->set = set;
1264
1265     object_property_add(obj, name, "string",
1266                         get ? property_get_str : NULL,
1267                         set ? property_set_str : NULL,
1268                         property_release_str,
1269                         prop, errp);
1270 }
1271
1272 typedef struct BoolProperty
1273 {
1274     bool (*get)(Object *, Error **);
1275     void (*set)(Object *, bool, Error **);
1276 } BoolProperty;
1277
1278 static void property_get_bool(Object *obj, Visitor *v, void *opaque,
1279                               const char *name, Error **errp)
1280 {
1281     BoolProperty *prop = opaque;
1282     bool value;
1283
1284     value = prop->get(obj, errp);
1285     visit_type_bool(v, &value, name, errp);
1286 }
1287
1288 static void property_set_bool(Object *obj, Visitor *v, void *opaque,
1289                               const char *name, Error **errp)
1290 {
1291     BoolProperty *prop = opaque;
1292     bool value;
1293     Error *local_err = NULL;
1294
1295     visit_type_bool(v, &value, name, &local_err);
1296     if (local_err) {
1297         error_propagate(errp, local_err);
1298         return;
1299     }
1300
1301     prop->set(obj, value, errp);
1302 }
1303
1304 static void property_release_bool(Object *obj, const char *name,
1305                                   void *opaque)
1306 {
1307     BoolProperty *prop = opaque;
1308     g_free(prop);
1309 }
1310
1311 void object_property_add_bool(Object *obj, const char *name,
1312                               bool (*get)(Object *, Error **),
1313                               void (*set)(Object *, bool, Error **),
1314                               Error **errp)
1315 {
1316     BoolProperty *prop = g_malloc0(sizeof(*prop));
1317
1318     prop->get = get;
1319     prop->set = set;
1320
1321     object_property_add(obj, name, "bool",
1322                         get ? property_get_bool : NULL,
1323                         set ? property_set_bool : NULL,
1324                         property_release_bool,
1325                         prop, errp);
1326 }
1327
1328 static char *qdev_get_type(Object *obj, Error **errp)
1329 {
1330     return g_strdup(object_get_typename(obj));
1331 }
1332
1333 static void object_instance_init(Object *obj)
1334 {
1335     object_property_add_str(obj, "type", qdev_get_type, NULL, NULL);
1336 }
1337
1338 static void register_types(void)
1339 {
1340     static TypeInfo interface_info = {
1341         .name = TYPE_INTERFACE,
1342         .class_size = sizeof(InterfaceClass),
1343         .abstract = true,
1344     };
1345
1346     static TypeInfo object_info = {
1347         .name = TYPE_OBJECT,
1348         .instance_size = sizeof(Object),
1349         .instance_init = object_instance_init,
1350         .abstract = true,
1351     };
1352
1353     type_interface = type_register_internal(&interface_info);
1354     type_register_internal(&object_info);
1355 }
1356
1357 type_init(register_types)