xref: /openbmc/qemu/qom/object.c (revision fc48ffc3)
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 "qom/object_interfaces.h"
15 #include "qemu-common.h"
16 #include "qapi/visitor.h"
17 #include "qapi-visit.h"
18 #include "qapi/string-input-visitor.h"
19 #include "qapi/string-output-visitor.h"
20 #include "qapi/qmp/qerror.h"
21 #include "trace.h"
22 
23 /* TODO: replace QObject with a simpler visitor to avoid a dependency
24  * of the QOM core on QObject?  */
25 #include "qom/qom-qobject.h"
26 #include "qapi/qmp/qobject.h"
27 #include "qapi/qmp/qbool.h"
28 #include "qapi/qmp/qint.h"
29 #include "qapi/qmp/qstring.h"
30 
31 #define MAX_INTERFACES 32
32 
33 typedef struct InterfaceImpl InterfaceImpl;
34 typedef struct TypeImpl TypeImpl;
35 
36 struct InterfaceImpl
37 {
38     const char *typename;
39 };
40 
41 struct TypeImpl
42 {
43     const char *name;
44 
45     size_t class_size;
46 
47     size_t instance_size;
48 
49     void (*class_init)(ObjectClass *klass, void *data);
50     void (*class_base_init)(ObjectClass *klass, void *data);
51     void (*class_finalize)(ObjectClass *klass, void *data);
52 
53     void *class_data;
54 
55     void (*instance_init)(Object *obj);
56     void (*instance_post_init)(Object *obj);
57     void (*instance_finalize)(Object *obj);
58 
59     bool abstract;
60 
61     const char *parent;
62     TypeImpl *parent_type;
63 
64     ObjectClass *class;
65 
66     int num_interfaces;
67     InterfaceImpl interfaces[MAX_INTERFACES];
68 };
69 
70 static Type type_interface;
71 
72 static GHashTable *type_table_get(void)
73 {
74     static GHashTable *type_table;
75 
76     if (type_table == NULL) {
77         type_table = g_hash_table_new(g_str_hash, g_str_equal);
78     }
79 
80     return type_table;
81 }
82 
83 static bool enumerating_types;
84 
85 static void type_table_add(TypeImpl *ti)
86 {
87     assert(!enumerating_types);
88     g_hash_table_insert(type_table_get(), (void *)ti->name, ti);
89 }
90 
91 static TypeImpl *type_table_lookup(const char *name)
92 {
93     return g_hash_table_lookup(type_table_get(), name);
94 }
95 
96 static TypeImpl *type_new(const TypeInfo *info)
97 {
98     TypeImpl *ti = g_malloc0(sizeof(*ti));
99     int i;
100 
101     g_assert(info->name != NULL);
102 
103     if (type_table_lookup(info->name) != NULL) {
104         fprintf(stderr, "Registering `%s' which already exists\n", info->name);
105         abort();
106     }
107 
108     ti->name = g_strdup(info->name);
109     ti->parent = g_strdup(info->parent);
110 
111     ti->class_size = info->class_size;
112     ti->instance_size = info->instance_size;
113 
114     ti->class_init = info->class_init;
115     ti->class_base_init = info->class_base_init;
116     ti->class_finalize = info->class_finalize;
117     ti->class_data = info->class_data;
118 
119     ti->instance_init = info->instance_init;
120     ti->instance_post_init = info->instance_post_init;
121     ti->instance_finalize = info->instance_finalize;
122 
123     ti->abstract = info->abstract;
124 
125     for (i = 0; info->interfaces && info->interfaces[i].type; i++) {
126         ti->interfaces[i].typename = g_strdup(info->interfaces[i].type);
127     }
128     ti->num_interfaces = i;
129 
130     return ti;
131 }
132 
133 static TypeImpl *type_register_internal(const TypeInfo *info)
134 {
135     TypeImpl *ti;
136     ti = type_new(info);
137 
138     type_table_add(ti);
139     return ti;
140 }
141 
142 TypeImpl *type_register(const TypeInfo *info)
143 {
144     assert(info->parent);
145     return type_register_internal(info);
146 }
147 
148 TypeImpl *type_register_static(const TypeInfo *info)
149 {
150     return type_register(info);
151 }
152 
153 static TypeImpl *type_get_by_name(const char *name)
154 {
155     if (name == NULL) {
156         return NULL;
157     }
158 
159     return type_table_lookup(name);
160 }
161 
162 static TypeImpl *type_get_parent(TypeImpl *type)
163 {
164     if (!type->parent_type && type->parent) {
165         type->parent_type = type_get_by_name(type->parent);
166         g_assert(type->parent_type != NULL);
167     }
168 
169     return type->parent_type;
170 }
171 
172 static bool type_has_parent(TypeImpl *type)
173 {
174     return (type->parent != NULL);
175 }
176 
177 static size_t type_class_get_size(TypeImpl *ti)
178 {
179     if (ti->class_size) {
180         return ti->class_size;
181     }
182 
183     if (type_has_parent(ti)) {
184         return type_class_get_size(type_get_parent(ti));
185     }
186 
187     return sizeof(ObjectClass);
188 }
189 
190 static size_t type_object_get_size(TypeImpl *ti)
191 {
192     if (ti->instance_size) {
193         return ti->instance_size;
194     }
195 
196     if (type_has_parent(ti)) {
197         return type_object_get_size(type_get_parent(ti));
198     }
199 
200     return 0;
201 }
202 
203 static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
204 {
205     assert(target_type);
206 
207     /* Check if typename is a direct ancestor of type */
208     while (type) {
209         if (type == target_type) {
210             return true;
211         }
212 
213         type = type_get_parent(type);
214     }
215 
216     return false;
217 }
218 
219 static void type_initialize(TypeImpl *ti);
220 
221 static void type_initialize_interface(TypeImpl *ti, TypeImpl *interface_type,
222                                       TypeImpl *parent_type)
223 {
224     InterfaceClass *new_iface;
225     TypeInfo info = { };
226     TypeImpl *iface_impl;
227 
228     info.parent = parent_type->name;
229     info.name = g_strdup_printf("%s::%s", ti->name, interface_type->name);
230     info.abstract = true;
231 
232     iface_impl = type_new(&info);
233     iface_impl->parent_type = parent_type;
234     type_initialize(iface_impl);
235     g_free((char *)info.name);
236 
237     new_iface = (InterfaceClass *)iface_impl->class;
238     new_iface->concrete_class = ti->class;
239     new_iface->interface_type = interface_type;
240 
241     ti->class->interfaces = g_slist_append(ti->class->interfaces,
242                                            iface_impl->class);
243 }
244 
245 static void type_initialize(TypeImpl *ti)
246 {
247     TypeImpl *parent;
248 
249     if (ti->class) {
250         return;
251     }
252 
253     ti->class_size = type_class_get_size(ti);
254     ti->instance_size = type_object_get_size(ti);
255 
256     ti->class = g_malloc0(ti->class_size);
257 
258     parent = type_get_parent(ti);
259     if (parent) {
260         type_initialize(parent);
261         GSList *e;
262         int i;
263 
264         g_assert(parent->class_size <= ti->class_size);
265         memcpy(ti->class, parent->class, parent->class_size);
266         ti->class->interfaces = NULL;
267 
268         for (e = parent->class->interfaces; e; e = e->next) {
269             InterfaceClass *iface = e->data;
270             ObjectClass *klass = OBJECT_CLASS(iface);
271 
272             type_initialize_interface(ti, iface->interface_type, klass->type);
273         }
274 
275         for (i = 0; i < ti->num_interfaces; i++) {
276             TypeImpl *t = type_get_by_name(ti->interfaces[i].typename);
277             for (e = ti->class->interfaces; e; e = e->next) {
278                 TypeImpl *target_type = OBJECT_CLASS(e->data)->type;
279 
280                 if (type_is_ancestor(target_type, t)) {
281                     break;
282                 }
283             }
284 
285             if (e) {
286                 continue;
287             }
288 
289             type_initialize_interface(ti, t, t);
290         }
291     }
292 
293     ti->class->type = ti;
294 
295     while (parent) {
296         if (parent->class_base_init) {
297             parent->class_base_init(ti->class, ti->class_data);
298         }
299         parent = type_get_parent(parent);
300     }
301 
302     if (ti->class_init) {
303         ti->class_init(ti->class, ti->class_data);
304     }
305 }
306 
307 static void object_init_with_type(Object *obj, TypeImpl *ti)
308 {
309     if (type_has_parent(ti)) {
310         object_init_with_type(obj, type_get_parent(ti));
311     }
312 
313     if (ti->instance_init) {
314         ti->instance_init(obj);
315     }
316 }
317 
318 static void object_post_init_with_type(Object *obj, TypeImpl *ti)
319 {
320     if (ti->instance_post_init) {
321         ti->instance_post_init(obj);
322     }
323 
324     if (type_has_parent(ti)) {
325         object_post_init_with_type(obj, type_get_parent(ti));
326     }
327 }
328 
329 void object_initialize_with_type(void *data, size_t size, TypeImpl *type)
330 {
331     Object *obj = data;
332 
333     g_assert(type != NULL);
334     type_initialize(type);
335 
336     g_assert(type->instance_size >= sizeof(Object));
337     g_assert(type->abstract == false);
338     g_assert(size >= type->instance_size);
339 
340     memset(obj, 0, type->instance_size);
341     obj->class = type->class;
342     object_ref(obj);
343     QTAILQ_INIT(&obj->properties);
344     object_init_with_type(obj, type);
345     object_post_init_with_type(obj, type);
346 }
347 
348 void object_initialize(void *data, size_t size, const char *typename)
349 {
350     TypeImpl *type = type_get_by_name(typename);
351 
352     object_initialize_with_type(data, size, type);
353 }
354 
355 static inline bool object_property_is_child(ObjectProperty *prop)
356 {
357     return strstart(prop->type, "child<", NULL);
358 }
359 
360 static void object_property_del_all(Object *obj)
361 {
362     while (!QTAILQ_EMPTY(&obj->properties)) {
363         ObjectProperty *prop = QTAILQ_FIRST(&obj->properties);
364 
365         QTAILQ_REMOVE(&obj->properties, prop, node);
366 
367         if (prop->release) {
368             prop->release(obj, prop->name, prop->opaque);
369         }
370 
371         g_free(prop->name);
372         g_free(prop->type);
373         g_free(prop->description);
374         g_free(prop);
375     }
376 }
377 
378 static void object_property_del_child(Object *obj, Object *child, Error **errp)
379 {
380     ObjectProperty *prop;
381 
382     QTAILQ_FOREACH(prop, &obj->properties, node) {
383         if (object_property_is_child(prop) && prop->opaque == child) {
384             object_property_del(obj, prop->name, errp);
385             break;
386         }
387     }
388 }
389 
390 void object_unparent(Object *obj)
391 {
392     if (obj->parent) {
393         object_property_del_child(obj->parent, obj, NULL);
394     }
395 }
396 
397 static void object_deinit(Object *obj, TypeImpl *type)
398 {
399     if (type->instance_finalize) {
400         type->instance_finalize(obj);
401     }
402 
403     if (type_has_parent(type)) {
404         object_deinit(obj, type_get_parent(type));
405     }
406 }
407 
408 static void object_finalize(void *data)
409 {
410     Object *obj = data;
411     TypeImpl *ti = obj->class->type;
412 
413     object_property_del_all(obj);
414     object_deinit(obj, ti);
415 
416     g_assert(obj->ref == 0);
417     if (obj->free) {
418         obj->free(obj);
419     }
420 }
421 
422 Object *object_new_with_type(Type type)
423 {
424     Object *obj;
425 
426     g_assert(type != NULL);
427     type_initialize(type);
428 
429     obj = g_malloc(type->instance_size);
430     object_initialize_with_type(obj, type->instance_size, type);
431     obj->free = g_free;
432 
433     return obj;
434 }
435 
436 Object *object_new(const char *typename)
437 {
438     TypeImpl *ti = type_get_by_name(typename);
439 
440     return object_new_with_type(ti);
441 }
442 
443 
444 Object *object_new_with_props(const char *typename,
445                               Object *parent,
446                               const char *id,
447                               Error **errp,
448                               ...)
449 {
450     va_list vargs;
451     Object *obj;
452 
453     va_start(vargs, errp);
454     obj = object_new_with_propv(typename, parent, id, errp, vargs);
455     va_end(vargs);
456 
457     return obj;
458 }
459 
460 
461 Object *object_new_with_propv(const char *typename,
462                               Object *parent,
463                               const char *id,
464                               Error **errp,
465                               va_list vargs)
466 {
467     Object *obj;
468     ObjectClass *klass;
469     Error *local_err = NULL;
470 
471     klass = object_class_by_name(typename);
472     if (!klass) {
473         error_setg(errp, "invalid object type: %s", typename);
474         return NULL;
475     }
476 
477     if (object_class_is_abstract(klass)) {
478         error_setg(errp, "object type '%s' is abstract", typename);
479         return NULL;
480     }
481     obj = object_new(typename);
482 
483     if (object_set_propv(obj, &local_err, vargs) < 0) {
484         goto error;
485     }
486 
487     object_property_add_child(parent, id, obj, &local_err);
488     if (local_err) {
489         goto error;
490     }
491 
492     if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) {
493         user_creatable_complete(obj, &local_err);
494         if (local_err) {
495             object_unparent(obj);
496             goto error;
497         }
498     }
499 
500     object_unref(OBJECT(obj));
501     return obj;
502 
503  error:
504     if (local_err) {
505         error_propagate(errp, local_err);
506     }
507     object_unref(obj);
508     return NULL;
509 }
510 
511 
512 int object_set_props(Object *obj,
513                      Error **errp,
514                      ...)
515 {
516     va_list vargs;
517     int ret;
518 
519     va_start(vargs, errp);
520     ret = object_set_propv(obj, errp, vargs);
521     va_end(vargs);
522 
523     return ret;
524 }
525 
526 
527 int object_set_propv(Object *obj,
528                      Error **errp,
529                      va_list vargs)
530 {
531     const char *propname;
532     Error *local_err = NULL;
533 
534     propname = va_arg(vargs, char *);
535     while (propname != NULL) {
536         const char *value = va_arg(vargs, char *);
537 
538         g_assert(value != NULL);
539         object_property_parse(obj, value, propname, &local_err);
540         if (local_err) {
541             error_propagate(errp, local_err);
542             return -1;
543         }
544         propname = va_arg(vargs, char *);
545     }
546 
547     return 0;
548 }
549 
550 
551 Object *object_dynamic_cast(Object *obj, const char *typename)
552 {
553     if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
554         return obj;
555     }
556 
557     return NULL;
558 }
559 
560 Object *object_dynamic_cast_assert(Object *obj, const char *typename,
561                                    const char *file, int line, const char *func)
562 {
563     trace_object_dynamic_cast_assert(obj ? obj->class->type->name : "(null)",
564                                      typename, file, line, func);
565 
566 #ifdef CONFIG_QOM_CAST_DEBUG
567     int i;
568     Object *inst;
569 
570     for (i = 0; obj && i < OBJECT_CLASS_CAST_CACHE; i++) {
571         if (obj->class->object_cast_cache[i] == typename) {
572             goto out;
573         }
574     }
575 
576     inst = object_dynamic_cast(obj, typename);
577 
578     if (!inst && obj) {
579         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
580                 file, line, func, obj, typename);
581         abort();
582     }
583 
584     assert(obj == inst);
585 
586     if (obj && obj == inst) {
587         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
588             obj->class->object_cast_cache[i - 1] =
589                     obj->class->object_cast_cache[i];
590         }
591         obj->class->object_cast_cache[i - 1] = typename;
592     }
593 
594 out:
595 #endif
596     return obj;
597 }
598 
599 ObjectClass *object_class_dynamic_cast(ObjectClass *class,
600                                        const char *typename)
601 {
602     ObjectClass *ret = NULL;
603     TypeImpl *target_type;
604     TypeImpl *type;
605 
606     if (!class) {
607         return NULL;
608     }
609 
610     /* A simple fast path that can trigger a lot for leaf classes.  */
611     type = class->type;
612     if (type->name == typename) {
613         return class;
614     }
615 
616     target_type = type_get_by_name(typename);
617     if (!target_type) {
618         /* target class type unknown, so fail the cast */
619         return NULL;
620     }
621 
622     if (type->class->interfaces &&
623             type_is_ancestor(target_type, type_interface)) {
624         int found = 0;
625         GSList *i;
626 
627         for (i = class->interfaces; i; i = i->next) {
628             ObjectClass *target_class = i->data;
629 
630             if (type_is_ancestor(target_class->type, target_type)) {
631                 ret = target_class;
632                 found++;
633             }
634          }
635 
636         /* The match was ambiguous, don't allow a cast */
637         if (found > 1) {
638             ret = NULL;
639         }
640     } else if (type_is_ancestor(type, target_type)) {
641         ret = class;
642     }
643 
644     return ret;
645 }
646 
647 ObjectClass *object_class_dynamic_cast_assert(ObjectClass *class,
648                                               const char *typename,
649                                               const char *file, int line,
650                                               const char *func)
651 {
652     ObjectClass *ret;
653 
654     trace_object_class_dynamic_cast_assert(class ? class->type->name : "(null)",
655                                            typename, file, line, func);
656 
657 #ifdef CONFIG_QOM_CAST_DEBUG
658     int i;
659 
660     for (i = 0; class && i < OBJECT_CLASS_CAST_CACHE; i++) {
661         if (class->class_cast_cache[i] == typename) {
662             ret = class;
663             goto out;
664         }
665     }
666 #else
667     if (!class || !class->interfaces) {
668         return class;
669     }
670 #endif
671 
672     ret = object_class_dynamic_cast(class, typename);
673     if (!ret && class) {
674         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
675                 file, line, func, class, typename);
676         abort();
677     }
678 
679 #ifdef CONFIG_QOM_CAST_DEBUG
680     if (class && ret == class) {
681         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
682             class->class_cast_cache[i - 1] = class->class_cast_cache[i];
683         }
684         class->class_cast_cache[i - 1] = typename;
685     }
686 out:
687 #endif
688     return ret;
689 }
690 
691 const char *object_get_typename(Object *obj)
692 {
693     return obj->class->type->name;
694 }
695 
696 ObjectClass *object_get_class(Object *obj)
697 {
698     return obj->class;
699 }
700 
701 bool object_class_is_abstract(ObjectClass *klass)
702 {
703     return klass->type->abstract;
704 }
705 
706 const char *object_class_get_name(ObjectClass *klass)
707 {
708     return klass->type->name;
709 }
710 
711 ObjectClass *object_class_by_name(const char *typename)
712 {
713     TypeImpl *type = type_get_by_name(typename);
714 
715     if (!type) {
716         return NULL;
717     }
718 
719     type_initialize(type);
720 
721     return type->class;
722 }
723 
724 ObjectClass *object_class_get_parent(ObjectClass *class)
725 {
726     TypeImpl *type = type_get_parent(class->type);
727 
728     if (!type) {
729         return NULL;
730     }
731 
732     type_initialize(type);
733 
734     return type->class;
735 }
736 
737 typedef struct OCFData
738 {
739     void (*fn)(ObjectClass *klass, void *opaque);
740     const char *implements_type;
741     bool include_abstract;
742     void *opaque;
743 } OCFData;
744 
745 static void object_class_foreach_tramp(gpointer key, gpointer value,
746                                        gpointer opaque)
747 {
748     OCFData *data = opaque;
749     TypeImpl *type = value;
750     ObjectClass *k;
751 
752     type_initialize(type);
753     k = type->class;
754 
755     if (!data->include_abstract && type->abstract) {
756         return;
757     }
758 
759     if (data->implements_type &&
760         !object_class_dynamic_cast(k, data->implements_type)) {
761         return;
762     }
763 
764     data->fn(k, data->opaque);
765 }
766 
767 void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
768                           const char *implements_type, bool include_abstract,
769                           void *opaque)
770 {
771     OCFData data = { fn, implements_type, include_abstract, opaque };
772 
773     enumerating_types = true;
774     g_hash_table_foreach(type_table_get(), object_class_foreach_tramp, &data);
775     enumerating_types = false;
776 }
777 
778 int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
779                          void *opaque)
780 {
781     ObjectProperty *prop, *next;
782     int ret = 0;
783 
784     QTAILQ_FOREACH_SAFE(prop, &obj->properties, node, next) {
785         if (object_property_is_child(prop)) {
786             ret = fn(prop->opaque, opaque);
787             if (ret != 0) {
788                 break;
789             }
790         }
791     }
792     return ret;
793 }
794 
795 static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
796 {
797     GSList **list = opaque;
798 
799     *list = g_slist_prepend(*list, klass);
800 }
801 
802 GSList *object_class_get_list(const char *implements_type,
803                               bool include_abstract)
804 {
805     GSList *list = NULL;
806 
807     object_class_foreach(object_class_get_list_tramp,
808                          implements_type, include_abstract, &list);
809     return list;
810 }
811 
812 void object_ref(Object *obj)
813 {
814     if (!obj) {
815         return;
816     }
817      atomic_inc(&obj->ref);
818 }
819 
820 void object_unref(Object *obj)
821 {
822     if (!obj) {
823         return;
824     }
825     g_assert(obj->ref > 0);
826 
827     /* parent always holds a reference to its children */
828     if (atomic_fetch_dec(&obj->ref) == 1) {
829         object_finalize(obj);
830     }
831 }
832 
833 ObjectProperty *
834 object_property_add(Object *obj, const char *name, const char *type,
835                     ObjectPropertyAccessor *get,
836                     ObjectPropertyAccessor *set,
837                     ObjectPropertyRelease *release,
838                     void *opaque, Error **errp)
839 {
840     ObjectProperty *prop;
841     size_t name_len = strlen(name);
842 
843     if (name_len >= 3 && !memcmp(name + name_len - 3, "[*]", 4)) {
844         int i;
845         ObjectProperty *ret;
846         char *name_no_array = g_strdup(name);
847 
848         name_no_array[name_len - 3] = '\0';
849         for (i = 0; ; ++i) {
850             char *full_name = g_strdup_printf("%s[%d]", name_no_array, i);
851 
852             ret = object_property_add(obj, full_name, type, get, set,
853                                       release, opaque, NULL);
854             g_free(full_name);
855             if (ret) {
856                 break;
857             }
858         }
859         g_free(name_no_array);
860         return ret;
861     }
862 
863     QTAILQ_FOREACH(prop, &obj->properties, node) {
864         if (strcmp(prop->name, name) == 0) {
865             error_setg(errp, "attempt to add duplicate property '%s'"
866                        " to object (type '%s')", name,
867                        object_get_typename(obj));
868             return NULL;
869         }
870     }
871 
872     prop = g_malloc0(sizeof(*prop));
873 
874     prop->name = g_strdup(name);
875     prop->type = g_strdup(type);
876 
877     prop->get = get;
878     prop->set = set;
879     prop->release = release;
880     prop->opaque = opaque;
881 
882     QTAILQ_INSERT_TAIL(&obj->properties, prop, node);
883     return prop;
884 }
885 
886 ObjectProperty *object_property_find(Object *obj, const char *name,
887                                      Error **errp)
888 {
889     ObjectProperty *prop;
890 
891     QTAILQ_FOREACH(prop, &obj->properties, node) {
892         if (strcmp(prop->name, name) == 0) {
893             return prop;
894         }
895     }
896 
897     error_setg(errp, "Property '.%s' not found", name);
898     return NULL;
899 }
900 
901 void object_property_del(Object *obj, const char *name, Error **errp)
902 {
903     ObjectProperty *prop = object_property_find(obj, name, errp);
904     if (prop == NULL) {
905         return;
906     }
907 
908     if (prop->release) {
909         prop->release(obj, name, prop->opaque);
910     }
911 
912     QTAILQ_REMOVE(&obj->properties, prop, node);
913 
914     g_free(prop->name);
915     g_free(prop->type);
916     g_free(prop->description);
917     g_free(prop);
918 }
919 
920 void object_property_get(Object *obj, Visitor *v, const char *name,
921                          Error **errp)
922 {
923     ObjectProperty *prop = object_property_find(obj, name, errp);
924     if (prop == NULL) {
925         return;
926     }
927 
928     if (!prop->get) {
929         error_set(errp, QERR_PERMISSION_DENIED);
930     } else {
931         prop->get(obj, v, prop->opaque, name, errp);
932     }
933 }
934 
935 void object_property_set(Object *obj, Visitor *v, const char *name,
936                          Error **errp)
937 {
938     ObjectProperty *prop = object_property_find(obj, name, errp);
939     if (prop == NULL) {
940         return;
941     }
942 
943     if (!prop->set) {
944         error_set(errp, QERR_PERMISSION_DENIED);
945     } else {
946         prop->set(obj, v, prop->opaque, name, errp);
947     }
948 }
949 
950 void object_property_set_str(Object *obj, const char *value,
951                              const char *name, Error **errp)
952 {
953     QString *qstr = qstring_from_str(value);
954     object_property_set_qobject(obj, QOBJECT(qstr), name, errp);
955 
956     QDECREF(qstr);
957 }
958 
959 char *object_property_get_str(Object *obj, const char *name,
960                               Error **errp)
961 {
962     QObject *ret = object_property_get_qobject(obj, name, errp);
963     QString *qstring;
964     char *retval;
965 
966     if (!ret) {
967         return NULL;
968     }
969     qstring = qobject_to_qstring(ret);
970     if (!qstring) {
971         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "string");
972         retval = NULL;
973     } else {
974         retval = g_strdup(qstring_get_str(qstring));
975     }
976 
977     QDECREF(qstring);
978     return retval;
979 }
980 
981 void object_property_set_link(Object *obj, Object *value,
982                               const char *name, Error **errp)
983 {
984     if (value) {
985         gchar *path = object_get_canonical_path(value);
986         object_property_set_str(obj, path, name, errp);
987         g_free(path);
988     } else {
989         object_property_set_str(obj, "", name, errp);
990     }
991 }
992 
993 Object *object_property_get_link(Object *obj, const char *name,
994                                  Error **errp)
995 {
996     char *str = object_property_get_str(obj, name, errp);
997     Object *target = NULL;
998 
999     if (str && *str) {
1000         target = object_resolve_path(str, NULL);
1001         if (!target) {
1002             error_set(errp, QERR_DEVICE_NOT_FOUND, str);
1003         }
1004     }
1005 
1006     g_free(str);
1007     return target;
1008 }
1009 
1010 void object_property_set_bool(Object *obj, bool value,
1011                               const char *name, Error **errp)
1012 {
1013     QBool *qbool = qbool_from_bool(value);
1014     object_property_set_qobject(obj, QOBJECT(qbool), name, errp);
1015 
1016     QDECREF(qbool);
1017 }
1018 
1019 bool object_property_get_bool(Object *obj, const char *name,
1020                               Error **errp)
1021 {
1022     QObject *ret = object_property_get_qobject(obj, name, errp);
1023     QBool *qbool;
1024     bool retval;
1025 
1026     if (!ret) {
1027         return false;
1028     }
1029     qbool = qobject_to_qbool(ret);
1030     if (!qbool) {
1031         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "boolean");
1032         retval = false;
1033     } else {
1034         retval = qbool_get_bool(qbool);
1035     }
1036 
1037     QDECREF(qbool);
1038     return retval;
1039 }
1040 
1041 void object_property_set_int(Object *obj, int64_t value,
1042                              const char *name, Error **errp)
1043 {
1044     QInt *qint = qint_from_int(value);
1045     object_property_set_qobject(obj, QOBJECT(qint), name, errp);
1046 
1047     QDECREF(qint);
1048 }
1049 
1050 int64_t object_property_get_int(Object *obj, const char *name,
1051                                 Error **errp)
1052 {
1053     QObject *ret = object_property_get_qobject(obj, name, errp);
1054     QInt *qint;
1055     int64_t retval;
1056 
1057     if (!ret) {
1058         return -1;
1059     }
1060     qint = qobject_to_qint(ret);
1061     if (!qint) {
1062         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "int");
1063         retval = -1;
1064     } else {
1065         retval = qint_get_int(qint);
1066     }
1067 
1068     QDECREF(qint);
1069     return retval;
1070 }
1071 
1072 typedef struct EnumProperty {
1073     const char * const *strings;
1074     int (*get)(Object *, Error **);
1075     void (*set)(Object *, int, Error **);
1076 } EnumProperty;
1077 
1078 int object_property_get_enum(Object *obj, const char *name,
1079                              const char *typename, Error **errp)
1080 {
1081     StringOutputVisitor *sov;
1082     StringInputVisitor *siv;
1083     char *str;
1084     int ret;
1085     ObjectProperty *prop = object_property_find(obj, name, errp);
1086     EnumProperty *enumprop;
1087 
1088     if (prop == NULL) {
1089         return 0;
1090     }
1091 
1092     if (!g_str_equal(prop->type, typename)) {
1093         error_setg(errp, "Property %s on %s is not '%s' enum type",
1094                    name, object_class_get_name(
1095                        object_get_class(obj)), typename);
1096         return 0;
1097     }
1098 
1099     enumprop = prop->opaque;
1100 
1101     sov = string_output_visitor_new(false);
1102     object_property_get(obj, string_output_get_visitor(sov), name, errp);
1103     str = string_output_get_string(sov);
1104     siv = string_input_visitor_new(str);
1105     string_output_visitor_cleanup(sov);
1106     visit_type_enum(string_input_get_visitor(siv),
1107                     &ret, enumprop->strings, NULL, name, errp);
1108 
1109     g_free(str);
1110     string_input_visitor_cleanup(siv);
1111 
1112     return ret;
1113 }
1114 
1115 void object_property_get_uint16List(Object *obj, const char *name,
1116                                     uint16List **list, Error **errp)
1117 {
1118     StringOutputVisitor *ov;
1119     StringInputVisitor *iv;
1120     char *str;
1121 
1122     ov = string_output_visitor_new(false);
1123     object_property_get(obj, string_output_get_visitor(ov),
1124                         name, errp);
1125     str = string_output_get_string(ov);
1126     iv = string_input_visitor_new(str);
1127     visit_type_uint16List(string_input_get_visitor(iv),
1128                           list, NULL, errp);
1129 
1130     g_free(str);
1131     string_output_visitor_cleanup(ov);
1132     string_input_visitor_cleanup(iv);
1133 }
1134 
1135 void object_property_parse(Object *obj, const char *string,
1136                            const char *name, Error **errp)
1137 {
1138     StringInputVisitor *mi;
1139     mi = string_input_visitor_new(string);
1140     object_property_set(obj, string_input_get_visitor(mi), name, errp);
1141 
1142     string_input_visitor_cleanup(mi);
1143 }
1144 
1145 char *object_property_print(Object *obj, const char *name, bool human,
1146                             Error **errp)
1147 {
1148     StringOutputVisitor *mo;
1149     char *string = NULL;
1150     Error *local_err = NULL;
1151 
1152     mo = string_output_visitor_new(human);
1153     object_property_get(obj, string_output_get_visitor(mo), name, &local_err);
1154     if (local_err) {
1155         error_propagate(errp, local_err);
1156         goto out;
1157     }
1158 
1159     string = string_output_get_string(mo);
1160 
1161 out:
1162     string_output_visitor_cleanup(mo);
1163     return string;
1164 }
1165 
1166 const char *object_property_get_type(Object *obj, const char *name, Error **errp)
1167 {
1168     ObjectProperty *prop = object_property_find(obj, name, errp);
1169     if (prop == NULL) {
1170         return NULL;
1171     }
1172 
1173     return prop->type;
1174 }
1175 
1176 Object *object_get_root(void)
1177 {
1178     static Object *root;
1179 
1180     if (!root) {
1181         root = object_new("container");
1182     }
1183 
1184     return root;
1185 }
1186 
1187 Object *object_get_objects_root(void)
1188 {
1189     return container_get(object_get_root(), "/objects");
1190 }
1191 
1192 static void object_get_child_property(Object *obj, Visitor *v, void *opaque,
1193                                       const char *name, Error **errp)
1194 {
1195     Object *child = opaque;
1196     gchar *path;
1197 
1198     path = object_get_canonical_path(child);
1199     visit_type_str(v, &path, name, errp);
1200     g_free(path);
1201 }
1202 
1203 static Object *object_resolve_child_property(Object *parent, void *opaque, const gchar *part)
1204 {
1205     return opaque;
1206 }
1207 
1208 static void object_finalize_child_property(Object *obj, const char *name,
1209                                            void *opaque)
1210 {
1211     Object *child = opaque;
1212 
1213     if (child->class->unparent) {
1214         (child->class->unparent)(child);
1215     }
1216     child->parent = NULL;
1217     object_unref(child);
1218 }
1219 
1220 void object_property_add_child(Object *obj, const char *name,
1221                                Object *child, Error **errp)
1222 {
1223     Error *local_err = NULL;
1224     gchar *type;
1225     ObjectProperty *op;
1226 
1227     if (child->parent != NULL) {
1228         error_setg(errp, "child object is already parented");
1229         return;
1230     }
1231 
1232     type = g_strdup_printf("child<%s>", object_get_typename(OBJECT(child)));
1233 
1234     op = object_property_add(obj, name, type, object_get_child_property, NULL,
1235                              object_finalize_child_property, child, &local_err);
1236     if (local_err) {
1237         error_propagate(errp, local_err);
1238         goto out;
1239     }
1240 
1241     op->resolve = object_resolve_child_property;
1242     object_ref(child);
1243     child->parent = obj;
1244 
1245 out:
1246     g_free(type);
1247 }
1248 
1249 void object_property_allow_set_link(Object *obj, const char *name,
1250                                     Object *val, Error **errp)
1251 {
1252     /* Allow the link to be set, always */
1253 }
1254 
1255 typedef struct {
1256     Object **child;
1257     void (*check)(Object *, const char *, Object *, Error **);
1258     ObjectPropertyLinkFlags flags;
1259 } LinkProperty;
1260 
1261 static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
1262                                      const char *name, Error **errp)
1263 {
1264     LinkProperty *lprop = opaque;
1265     Object **child = lprop->child;
1266     gchar *path;
1267 
1268     if (*child) {
1269         path = object_get_canonical_path(*child);
1270         visit_type_str(v, &path, name, errp);
1271         g_free(path);
1272     } else {
1273         path = (gchar *)"";
1274         visit_type_str(v, &path, name, errp);
1275     }
1276 }
1277 
1278 /*
1279  * object_resolve_link:
1280  *
1281  * Lookup an object and ensure its type matches the link property type.  This
1282  * is similar to object_resolve_path() except type verification against the
1283  * link property is performed.
1284  *
1285  * Returns: The matched object or NULL on path lookup failures.
1286  */
1287 static Object *object_resolve_link(Object *obj, const char *name,
1288                                    const char *path, Error **errp)
1289 {
1290     const char *type;
1291     gchar *target_type;
1292     bool ambiguous = false;
1293     Object *target;
1294 
1295     /* Go from link<FOO> to FOO.  */
1296     type = object_property_get_type(obj, name, NULL);
1297     target_type = g_strndup(&type[5], strlen(type) - 6);
1298     target = object_resolve_path_type(path, target_type, &ambiguous);
1299 
1300     if (ambiguous) {
1301         error_set(errp, ERROR_CLASS_GENERIC_ERROR,
1302                   "Path '%s' does not uniquely identify an object", path);
1303     } else if (!target) {
1304         target = object_resolve_path(path, &ambiguous);
1305         if (target || ambiguous) {
1306             error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
1307         } else {
1308             error_set(errp, QERR_DEVICE_NOT_FOUND, path);
1309         }
1310         target = NULL;
1311     }
1312     g_free(target_type);
1313 
1314     return target;
1315 }
1316 
1317 static void object_set_link_property(Object *obj, Visitor *v, void *opaque,
1318                                      const char *name, Error **errp)
1319 {
1320     Error *local_err = NULL;
1321     LinkProperty *prop = opaque;
1322     Object **child = prop->child;
1323     Object *old_target = *child;
1324     Object *new_target = NULL;
1325     char *path = NULL;
1326 
1327     visit_type_str(v, &path, name, &local_err);
1328 
1329     if (!local_err && strcmp(path, "") != 0) {
1330         new_target = object_resolve_link(obj, name, path, &local_err);
1331     }
1332 
1333     g_free(path);
1334     if (local_err) {
1335         error_propagate(errp, local_err);
1336         return;
1337     }
1338 
1339     prop->check(obj, name, new_target, &local_err);
1340     if (local_err) {
1341         error_propagate(errp, local_err);
1342         return;
1343     }
1344 
1345     object_ref(new_target);
1346     *child = new_target;
1347     object_unref(old_target);
1348 }
1349 
1350 static Object *object_resolve_link_property(Object *parent, void *opaque, const gchar *part)
1351 {
1352     LinkProperty *lprop = opaque;
1353 
1354     return *lprop->child;
1355 }
1356 
1357 static void object_release_link_property(Object *obj, const char *name,
1358                                          void *opaque)
1359 {
1360     LinkProperty *prop = opaque;
1361 
1362     if ((prop->flags & OBJ_PROP_LINK_UNREF_ON_RELEASE) && *prop->child) {
1363         object_unref(*prop->child);
1364     }
1365     g_free(prop);
1366 }
1367 
1368 void object_property_add_link(Object *obj, const char *name,
1369                               const char *type, Object **child,
1370                               void (*check)(Object *, const char *,
1371                                             Object *, Error **),
1372                               ObjectPropertyLinkFlags flags,
1373                               Error **errp)
1374 {
1375     Error *local_err = NULL;
1376     LinkProperty *prop = g_malloc(sizeof(*prop));
1377     gchar *full_type;
1378     ObjectProperty *op;
1379 
1380     prop->child = child;
1381     prop->check = check;
1382     prop->flags = flags;
1383 
1384     full_type = g_strdup_printf("link<%s>", type);
1385 
1386     op = object_property_add(obj, name, full_type,
1387                              object_get_link_property,
1388                              check ? object_set_link_property : NULL,
1389                              object_release_link_property,
1390                              prop,
1391                              &local_err);
1392     if (local_err) {
1393         error_propagate(errp, local_err);
1394         g_free(prop);
1395         goto out;
1396     }
1397 
1398     op->resolve = object_resolve_link_property;
1399 
1400 out:
1401     g_free(full_type);
1402 }
1403 
1404 void object_property_add_const_link(Object *obj, const char *name,
1405                                     Object *target, Error **errp)
1406 {
1407     char *link_type;
1408     ObjectProperty *op;
1409 
1410     link_type = g_strdup_printf("link<%s>", object_get_typename(target));
1411     op = object_property_add(obj, name, link_type,
1412                              object_get_child_property, NULL,
1413                              NULL, target, errp);
1414     if (op != NULL) {
1415         op->resolve = object_resolve_child_property;
1416     }
1417     g_free(link_type);
1418 }
1419 
1420 gchar *object_get_canonical_path_component(Object *obj)
1421 {
1422     ObjectProperty *prop = NULL;
1423 
1424     g_assert(obj);
1425     g_assert(obj->parent != NULL);
1426 
1427     QTAILQ_FOREACH(prop, &obj->parent->properties, node) {
1428         if (!object_property_is_child(prop)) {
1429             continue;
1430         }
1431 
1432         if (prop->opaque == obj) {
1433             return g_strdup(prop->name);
1434         }
1435     }
1436 
1437     /* obj had a parent but was not a child, should never happen */
1438     g_assert_not_reached();
1439     return NULL;
1440 }
1441 
1442 gchar *object_get_canonical_path(Object *obj)
1443 {
1444     Object *root = object_get_root();
1445     char *newpath, *path = NULL;
1446 
1447     while (obj != root) {
1448         char *component = object_get_canonical_path_component(obj);
1449 
1450         if (path) {
1451             newpath = g_strdup_printf("%s/%s", component, path);
1452             g_free(component);
1453             g_free(path);
1454             path = newpath;
1455         } else {
1456             path = component;
1457         }
1458 
1459         obj = obj->parent;
1460     }
1461 
1462     newpath = g_strdup_printf("/%s", path ? path : "");
1463     g_free(path);
1464 
1465     return newpath;
1466 }
1467 
1468 Object *object_resolve_path_component(Object *parent, const gchar *part)
1469 {
1470     ObjectProperty *prop = object_property_find(parent, part, NULL);
1471     if (prop == NULL) {
1472         return NULL;
1473     }
1474 
1475     if (prop->resolve) {
1476         return prop->resolve(parent, prop->opaque, part);
1477     } else {
1478         return NULL;
1479     }
1480 }
1481 
1482 static Object *object_resolve_abs_path(Object *parent,
1483                                           gchar **parts,
1484                                           const char *typename,
1485                                           int index)
1486 {
1487     Object *child;
1488 
1489     if (parts[index] == NULL) {
1490         return object_dynamic_cast(parent, typename);
1491     }
1492 
1493     if (strcmp(parts[index], "") == 0) {
1494         return object_resolve_abs_path(parent, parts, typename, index + 1);
1495     }
1496 
1497     child = object_resolve_path_component(parent, parts[index]);
1498     if (!child) {
1499         return NULL;
1500     }
1501 
1502     return object_resolve_abs_path(child, parts, typename, index + 1);
1503 }
1504 
1505 static Object *object_resolve_partial_path(Object *parent,
1506                                               gchar **parts,
1507                                               const char *typename,
1508                                               bool *ambiguous)
1509 {
1510     Object *obj;
1511     ObjectProperty *prop;
1512 
1513     obj = object_resolve_abs_path(parent, parts, typename, 0);
1514 
1515     QTAILQ_FOREACH(prop, &parent->properties, node) {
1516         Object *found;
1517 
1518         if (!object_property_is_child(prop)) {
1519             continue;
1520         }
1521 
1522         found = object_resolve_partial_path(prop->opaque, parts,
1523                                             typename, ambiguous);
1524         if (found) {
1525             if (obj) {
1526                 if (ambiguous) {
1527                     *ambiguous = true;
1528                 }
1529                 return NULL;
1530             }
1531             obj = found;
1532         }
1533 
1534         if (ambiguous && *ambiguous) {
1535             return NULL;
1536         }
1537     }
1538 
1539     return obj;
1540 }
1541 
1542 Object *object_resolve_path_type(const char *path, const char *typename,
1543                                  bool *ambiguous)
1544 {
1545     Object *obj;
1546     gchar **parts;
1547 
1548     parts = g_strsplit(path, "/", 0);
1549     assert(parts);
1550 
1551     if (parts[0] == NULL || strcmp(parts[0], "") != 0) {
1552         if (ambiguous) {
1553             *ambiguous = false;
1554         }
1555         obj = object_resolve_partial_path(object_get_root(), parts,
1556                                           typename, ambiguous);
1557     } else {
1558         obj = object_resolve_abs_path(object_get_root(), parts, typename, 1);
1559     }
1560 
1561     g_strfreev(parts);
1562 
1563     return obj;
1564 }
1565 
1566 Object *object_resolve_path(const char *path, bool *ambiguous)
1567 {
1568     return object_resolve_path_type(path, TYPE_OBJECT, ambiguous);
1569 }
1570 
1571 typedef struct StringProperty
1572 {
1573     char *(*get)(Object *, Error **);
1574     void (*set)(Object *, const char *, Error **);
1575 } StringProperty;
1576 
1577 static void property_get_str(Object *obj, Visitor *v, void *opaque,
1578                              const char *name, Error **errp)
1579 {
1580     StringProperty *prop = opaque;
1581     char *value;
1582 
1583     value = prop->get(obj, errp);
1584     if (value) {
1585         visit_type_str(v, &value, name, errp);
1586         g_free(value);
1587     }
1588 }
1589 
1590 static void property_set_str(Object *obj, Visitor *v, void *opaque,
1591                              const char *name, Error **errp)
1592 {
1593     StringProperty *prop = opaque;
1594     char *value;
1595     Error *local_err = NULL;
1596 
1597     visit_type_str(v, &value, name, &local_err);
1598     if (local_err) {
1599         error_propagate(errp, local_err);
1600         return;
1601     }
1602 
1603     prop->set(obj, value, errp);
1604     g_free(value);
1605 }
1606 
1607 static void property_release_str(Object *obj, const char *name,
1608                                  void *opaque)
1609 {
1610     StringProperty *prop = opaque;
1611     g_free(prop);
1612 }
1613 
1614 void object_property_add_str(Object *obj, const char *name,
1615                            char *(*get)(Object *, Error **),
1616                            void (*set)(Object *, const char *, Error **),
1617                            Error **errp)
1618 {
1619     Error *local_err = NULL;
1620     StringProperty *prop = g_malloc0(sizeof(*prop));
1621 
1622     prop->get = get;
1623     prop->set = set;
1624 
1625     object_property_add(obj, name, "string",
1626                         get ? property_get_str : NULL,
1627                         set ? property_set_str : NULL,
1628                         property_release_str,
1629                         prop, &local_err);
1630     if (local_err) {
1631         error_propagate(errp, local_err);
1632         g_free(prop);
1633     }
1634 }
1635 
1636 typedef struct BoolProperty
1637 {
1638     bool (*get)(Object *, Error **);
1639     void (*set)(Object *, bool, Error **);
1640 } BoolProperty;
1641 
1642 static void property_get_bool(Object *obj, Visitor *v, void *opaque,
1643                               const char *name, Error **errp)
1644 {
1645     BoolProperty *prop = opaque;
1646     bool value;
1647 
1648     value = prop->get(obj, errp);
1649     visit_type_bool(v, &value, name, errp);
1650 }
1651 
1652 static void property_set_bool(Object *obj, Visitor *v, void *opaque,
1653                               const char *name, Error **errp)
1654 {
1655     BoolProperty *prop = opaque;
1656     bool value;
1657     Error *local_err = NULL;
1658 
1659     visit_type_bool(v, &value, name, &local_err);
1660     if (local_err) {
1661         error_propagate(errp, local_err);
1662         return;
1663     }
1664 
1665     prop->set(obj, value, errp);
1666 }
1667 
1668 static void property_release_bool(Object *obj, const char *name,
1669                                   void *opaque)
1670 {
1671     BoolProperty *prop = opaque;
1672     g_free(prop);
1673 }
1674 
1675 void object_property_add_bool(Object *obj, const char *name,
1676                               bool (*get)(Object *, Error **),
1677                               void (*set)(Object *, bool, Error **),
1678                               Error **errp)
1679 {
1680     Error *local_err = NULL;
1681     BoolProperty *prop = g_malloc0(sizeof(*prop));
1682 
1683     prop->get = get;
1684     prop->set = set;
1685 
1686     object_property_add(obj, name, "bool",
1687                         get ? property_get_bool : NULL,
1688                         set ? property_set_bool : NULL,
1689                         property_release_bool,
1690                         prop, &local_err);
1691     if (local_err) {
1692         error_propagate(errp, local_err);
1693         g_free(prop);
1694     }
1695 }
1696 
1697 static void property_get_enum(Object *obj, Visitor *v, void *opaque,
1698                               const char *name, Error **errp)
1699 {
1700     EnumProperty *prop = opaque;
1701     int value;
1702 
1703     value = prop->get(obj, errp);
1704     visit_type_enum(v, &value, prop->strings, NULL, name, errp);
1705 }
1706 
1707 static void property_set_enum(Object *obj, Visitor *v, void *opaque,
1708                               const char *name, Error **errp)
1709 {
1710     EnumProperty *prop = opaque;
1711     int value;
1712 
1713     visit_type_enum(v, &value, prop->strings, NULL, name, errp);
1714     prop->set(obj, value, errp);
1715 }
1716 
1717 static void property_release_enum(Object *obj, const char *name,
1718                                   void *opaque)
1719 {
1720     EnumProperty *prop = opaque;
1721     g_free(prop);
1722 }
1723 
1724 void object_property_add_enum(Object *obj, const char *name,
1725                               const char *typename,
1726                               const char * const *strings,
1727                               int (*get)(Object *, Error **),
1728                               void (*set)(Object *, int, Error **),
1729                               Error **errp)
1730 {
1731     Error *local_err = NULL;
1732     EnumProperty *prop = g_malloc(sizeof(*prop));
1733 
1734     prop->strings = strings;
1735     prop->get = get;
1736     prop->set = set;
1737 
1738     object_property_add(obj, name, typename,
1739                         get ? property_get_enum : NULL,
1740                         set ? property_set_enum : NULL,
1741                         property_release_enum,
1742                         prop, &local_err);
1743     if (local_err) {
1744         error_propagate(errp, local_err);
1745         g_free(prop);
1746     }
1747 }
1748 
1749 typedef struct TMProperty {
1750     void (*get)(Object *, struct tm *, Error **);
1751 } TMProperty;
1752 
1753 static void property_get_tm(Object *obj, Visitor *v, void *opaque,
1754                             const char *name, Error **errp)
1755 {
1756     TMProperty *prop = opaque;
1757     Error *err = NULL;
1758     struct tm value;
1759 
1760     prop->get(obj, &value, &err);
1761     if (err) {
1762         goto out;
1763     }
1764 
1765     visit_start_struct(v, NULL, "struct tm", name, 0, &err);
1766     if (err) {
1767         goto out;
1768     }
1769     visit_type_int32(v, &value.tm_year, "tm_year", &err);
1770     if (err) {
1771         goto out_end;
1772     }
1773     visit_type_int32(v, &value.tm_mon, "tm_mon", &err);
1774     if (err) {
1775         goto out_end;
1776     }
1777     visit_type_int32(v, &value.tm_mday, "tm_mday", &err);
1778     if (err) {
1779         goto out_end;
1780     }
1781     visit_type_int32(v, &value.tm_hour, "tm_hour", &err);
1782     if (err) {
1783         goto out_end;
1784     }
1785     visit_type_int32(v, &value.tm_min, "tm_min", &err);
1786     if (err) {
1787         goto out_end;
1788     }
1789     visit_type_int32(v, &value.tm_sec, "tm_sec", &err);
1790     if (err) {
1791         goto out_end;
1792     }
1793 out_end:
1794     error_propagate(errp, err);
1795     err = NULL;
1796     visit_end_struct(v, errp);
1797 out:
1798     error_propagate(errp, err);
1799 
1800 }
1801 
1802 static void property_release_tm(Object *obj, const char *name,
1803                                 void *opaque)
1804 {
1805     TMProperty *prop = opaque;
1806     g_free(prop);
1807 }
1808 
1809 void object_property_add_tm(Object *obj, const char *name,
1810                             void (*get)(Object *, struct tm *, Error **),
1811                             Error **errp)
1812 {
1813     Error *local_err = NULL;
1814     TMProperty *prop = g_malloc0(sizeof(*prop));
1815 
1816     prop->get = get;
1817 
1818     object_property_add(obj, name, "struct tm",
1819                         get ? property_get_tm : NULL, NULL,
1820                         property_release_tm,
1821                         prop, &local_err);
1822     if (local_err) {
1823         error_propagate(errp, local_err);
1824         g_free(prop);
1825     }
1826 }
1827 
1828 static char *qdev_get_type(Object *obj, Error **errp)
1829 {
1830     return g_strdup(object_get_typename(obj));
1831 }
1832 
1833 static void property_get_uint8_ptr(Object *obj, Visitor *v,
1834                                    void *opaque, const char *name,
1835                                    Error **errp)
1836 {
1837     uint8_t value = *(uint8_t *)opaque;
1838     visit_type_uint8(v, &value, name, errp);
1839 }
1840 
1841 static void property_get_uint16_ptr(Object *obj, Visitor *v,
1842                                    void *opaque, const char *name,
1843                                    Error **errp)
1844 {
1845     uint16_t value = *(uint16_t *)opaque;
1846     visit_type_uint16(v, &value, name, errp);
1847 }
1848 
1849 static void property_get_uint32_ptr(Object *obj, Visitor *v,
1850                                    void *opaque, const char *name,
1851                                    Error **errp)
1852 {
1853     uint32_t value = *(uint32_t *)opaque;
1854     visit_type_uint32(v, &value, name, errp);
1855 }
1856 
1857 static void property_get_uint64_ptr(Object *obj, Visitor *v,
1858                                    void *opaque, const char *name,
1859                                    Error **errp)
1860 {
1861     uint64_t value = *(uint64_t *)opaque;
1862     visit_type_uint64(v, &value, name, errp);
1863 }
1864 
1865 void object_property_add_uint8_ptr(Object *obj, const char *name,
1866                                    const uint8_t *v, Error **errp)
1867 {
1868     object_property_add(obj, name, "uint8", property_get_uint8_ptr,
1869                         NULL, NULL, (void *)v, errp);
1870 }
1871 
1872 void object_property_add_uint16_ptr(Object *obj, const char *name,
1873                                     const uint16_t *v, Error **errp)
1874 {
1875     object_property_add(obj, name, "uint16", property_get_uint16_ptr,
1876                         NULL, NULL, (void *)v, errp);
1877 }
1878 
1879 void object_property_add_uint32_ptr(Object *obj, const char *name,
1880                                     const uint32_t *v, Error **errp)
1881 {
1882     object_property_add(obj, name, "uint32", property_get_uint32_ptr,
1883                         NULL, NULL, (void *)v, errp);
1884 }
1885 
1886 void object_property_add_uint64_ptr(Object *obj, const char *name,
1887                                     const uint64_t *v, Error **errp)
1888 {
1889     object_property_add(obj, name, "uint64", property_get_uint64_ptr,
1890                         NULL, NULL, (void *)v, errp);
1891 }
1892 
1893 typedef struct {
1894     Object *target_obj;
1895     char *target_name;
1896 } AliasProperty;
1897 
1898 static void property_get_alias(Object *obj, struct Visitor *v, void *opaque,
1899                                const char *name, Error **errp)
1900 {
1901     AliasProperty *prop = opaque;
1902 
1903     object_property_get(prop->target_obj, v, prop->target_name, errp);
1904 }
1905 
1906 static void property_set_alias(Object *obj, struct Visitor *v, void *opaque,
1907                                const char *name, Error **errp)
1908 {
1909     AliasProperty *prop = opaque;
1910 
1911     object_property_set(prop->target_obj, v, prop->target_name, errp);
1912 }
1913 
1914 static Object *property_resolve_alias(Object *obj, void *opaque,
1915                                       const gchar *part)
1916 {
1917     AliasProperty *prop = opaque;
1918 
1919     return object_resolve_path_component(prop->target_obj, prop->target_name);
1920 }
1921 
1922 static void property_release_alias(Object *obj, const char *name, void *opaque)
1923 {
1924     AliasProperty *prop = opaque;
1925 
1926     g_free(prop->target_name);
1927     g_free(prop);
1928 }
1929 
1930 void object_property_add_alias(Object *obj, const char *name,
1931                                Object *target_obj, const char *target_name,
1932                                Error **errp)
1933 {
1934     AliasProperty *prop;
1935     ObjectProperty *op;
1936     ObjectProperty *target_prop;
1937     gchar *prop_type;
1938     Error *local_err = NULL;
1939 
1940     target_prop = object_property_find(target_obj, target_name, errp);
1941     if (!target_prop) {
1942         return;
1943     }
1944 
1945     if (object_property_is_child(target_prop)) {
1946         prop_type = g_strdup_printf("link%s",
1947                                     target_prop->type + strlen("child"));
1948     } else {
1949         prop_type = g_strdup(target_prop->type);
1950     }
1951 
1952     prop = g_malloc(sizeof(*prop));
1953     prop->target_obj = target_obj;
1954     prop->target_name = g_strdup(target_name);
1955 
1956     op = object_property_add(obj, name, prop_type,
1957                              property_get_alias,
1958                              property_set_alias,
1959                              property_release_alias,
1960                              prop, &local_err);
1961     if (local_err) {
1962         error_propagate(errp, local_err);
1963         g_free(prop);
1964         goto out;
1965     }
1966     op->resolve = property_resolve_alias;
1967 
1968     object_property_set_description(obj, op->name,
1969                                     target_prop->description,
1970                                     &error_abort);
1971 
1972 out:
1973     g_free(prop_type);
1974 }
1975 
1976 void object_property_set_description(Object *obj, const char *name,
1977                                      const char *description, Error **errp)
1978 {
1979     ObjectProperty *op;
1980 
1981     op = object_property_find(obj, name, errp);
1982     if (!op) {
1983         return;
1984     }
1985 
1986     g_free(op->description);
1987     op->description = g_strdup(description);
1988 }
1989 
1990 static void object_instance_init(Object *obj)
1991 {
1992     object_property_add_str(obj, "type", qdev_get_type, NULL, NULL);
1993 }
1994 
1995 static void register_types(void)
1996 {
1997     static TypeInfo interface_info = {
1998         .name = TYPE_INTERFACE,
1999         .class_size = sizeof(InterfaceClass),
2000         .abstract = true,
2001     };
2002 
2003     static TypeInfo object_info = {
2004         .name = TYPE_OBJECT,
2005         .instance_size = sizeof(Object),
2006         .instance_init = object_instance_init,
2007         .abstract = true,
2008     };
2009 
2010     type_interface = type_register_internal(&interface_info);
2011     type_register_internal(&object_info);
2012 }
2013 
2014 type_init(register_types)
2015