xref: /openbmc/qemu/qom/object.c (revision f173d57a)
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-visit.h"
17 #include "qapi/string-input-visitor.h"
18 #include "qapi/string-output-visitor.h"
19 #include "qapi/qmp/qerror.h"
20 #include "trace.h"
21 
22 /* TODO: replace QObject with a simpler visitor to avoid a dependency
23  * of the QOM core on QObject?  */
24 #include "qom/qom-qobject.h"
25 #include "qapi/qmp/qobject.h"
26 #include "qapi/qmp/qbool.h"
27 #include "qapi/qmp/qint.h"
28 #include "qapi/qmp/qstring.h"
29 
30 #define MAX_INTERFACES 32
31 
32 typedef struct InterfaceImpl InterfaceImpl;
33 typedef struct TypeImpl TypeImpl;
34 
35 struct InterfaceImpl
36 {
37     const char *typename;
38 };
39 
40 struct TypeImpl
41 {
42     const char *name;
43 
44     size_t class_size;
45 
46     size_t instance_size;
47 
48     void (*class_init)(ObjectClass *klass, void *data);
49     void (*class_base_init)(ObjectClass *klass, void *data);
50     void (*class_finalize)(ObjectClass *klass, void *data);
51 
52     void *class_data;
53 
54     void (*instance_init)(Object *obj);
55     void (*instance_post_init)(Object *obj);
56     void (*instance_finalize)(Object *obj);
57 
58     bool abstract;
59 
60     const char *parent;
61     TypeImpl *parent_type;
62 
63     ObjectClass *class;
64 
65     int num_interfaces;
66     InterfaceImpl interfaces[MAX_INTERFACES];
67 };
68 
69 static Type type_interface;
70 
71 static GHashTable *type_table_get(void)
72 {
73     static GHashTable *type_table;
74 
75     if (type_table == NULL) {
76         type_table = g_hash_table_new(g_str_hash, g_str_equal);
77     }
78 
79     return type_table;
80 }
81 
82 static bool enumerating_types;
83 
84 static void type_table_add(TypeImpl *ti)
85 {
86     assert(!enumerating_types);
87     g_hash_table_insert(type_table_get(), (void *)ti->name, ti);
88 }
89 
90 static TypeImpl *type_table_lookup(const char *name)
91 {
92     return g_hash_table_lookup(type_table_get(), name);
93 }
94 
95 static TypeImpl *type_new(const TypeInfo *info)
96 {
97     TypeImpl *ti = g_malloc0(sizeof(*ti));
98     int i;
99 
100     g_assert(info->name != NULL);
101 
102     if (type_table_lookup(info->name) != NULL) {
103         fprintf(stderr, "Registering `%s' which already exists\n", info->name);
104         abort();
105     }
106 
107     ti->name = g_strdup(info->name);
108     ti->parent = g_strdup(info->parent);
109 
110     ti->class_size = info->class_size;
111     ti->instance_size = info->instance_size;
112 
113     ti->class_init = info->class_init;
114     ti->class_base_init = info->class_base_init;
115     ti->class_finalize = info->class_finalize;
116     ti->class_data = info->class_data;
117 
118     ti->instance_init = info->instance_init;
119     ti->instance_post_init = info->instance_post_init;
120     ti->instance_finalize = info->instance_finalize;
121 
122     ti->abstract = info->abstract;
123 
124     for (i = 0; info->interfaces && info->interfaces[i].type; i++) {
125         ti->interfaces[i].typename = g_strdup(info->interfaces[i].type);
126     }
127     ti->num_interfaces = i;
128 
129     return ti;
130 }
131 
132 static TypeImpl *type_register_internal(const TypeInfo *info)
133 {
134     TypeImpl *ti;
135     ti = type_new(info);
136 
137     type_table_add(ti);
138     return ti;
139 }
140 
141 TypeImpl *type_register(const TypeInfo *info)
142 {
143     assert(info->parent);
144     return type_register_internal(info);
145 }
146 
147 TypeImpl *type_register_static(const TypeInfo *info)
148 {
149     return type_register(info);
150 }
151 
152 static TypeImpl *type_get_by_name(const char *name)
153 {
154     if (name == NULL) {
155         return NULL;
156     }
157 
158     return type_table_lookup(name);
159 }
160 
161 static TypeImpl *type_get_parent(TypeImpl *type)
162 {
163     if (!type->parent_type && type->parent) {
164         type->parent_type = type_get_by_name(type->parent);
165         g_assert(type->parent_type != NULL);
166     }
167 
168     return type->parent_type;
169 }
170 
171 static bool type_has_parent(TypeImpl *type)
172 {
173     return (type->parent != NULL);
174 }
175 
176 static size_t type_class_get_size(TypeImpl *ti)
177 {
178     if (ti->class_size) {
179         return ti->class_size;
180     }
181 
182     if (type_has_parent(ti)) {
183         return type_class_get_size(type_get_parent(ti));
184     }
185 
186     return sizeof(ObjectClass);
187 }
188 
189 static size_t type_object_get_size(TypeImpl *ti)
190 {
191     if (ti->instance_size) {
192         return ti->instance_size;
193     }
194 
195     if (type_has_parent(ti)) {
196         return type_object_get_size(type_get_parent(ti));
197     }
198 
199     return 0;
200 }
201 
202 static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
203 {
204     assert(target_type);
205 
206     /* Check if typename is a direct ancestor of type */
207     while (type) {
208         if (type == target_type) {
209             return true;
210         }
211 
212         type = type_get_parent(type);
213     }
214 
215     return false;
216 }
217 
218 static void type_initialize(TypeImpl *ti);
219 
220 static void type_initialize_interface(TypeImpl *ti, TypeImpl *interface_type,
221                                       TypeImpl *parent_type)
222 {
223     InterfaceClass *new_iface;
224     TypeInfo info = { };
225     TypeImpl *iface_impl;
226 
227     info.parent = parent_type->name;
228     info.name = g_strdup_printf("%s::%s", ti->name, interface_type->name);
229     info.abstract = true;
230 
231     iface_impl = type_new(&info);
232     iface_impl->parent_type = parent_type;
233     type_initialize(iface_impl);
234     g_free((char *)info.name);
235 
236     new_iface = (InterfaceClass *)iface_impl->class;
237     new_iface->concrete_class = ti->class;
238     new_iface->interface_type = interface_type;
239 
240     ti->class->interfaces = g_slist_append(ti->class->interfaces,
241                                            iface_impl->class);
242 }
243 
244 static void type_initialize(TypeImpl *ti)
245 {
246     TypeImpl *parent;
247 
248     if (ti->class) {
249         return;
250     }
251 
252     ti->class_size = type_class_get_size(ti);
253     ti->instance_size = type_object_get_size(ti);
254 
255     ti->class = g_malloc0(ti->class_size);
256 
257     parent = type_get_parent(ti);
258     if (parent) {
259         type_initialize(parent);
260         GSList *e;
261         int i;
262 
263         g_assert(parent->class_size <= ti->class_size);
264         memcpy(ti->class, parent->class, parent->class_size);
265         ti->class->interfaces = NULL;
266 
267         for (e = parent->class->interfaces; e; e = e->next) {
268             InterfaceClass *iface = e->data;
269             ObjectClass *klass = OBJECT_CLASS(iface);
270 
271             type_initialize_interface(ti, iface->interface_type, klass->type);
272         }
273 
274         for (i = 0; i < ti->num_interfaces; i++) {
275             TypeImpl *t = type_get_by_name(ti->interfaces[i].typename);
276             for (e = ti->class->interfaces; e; e = e->next) {
277                 TypeImpl *target_type = OBJECT_CLASS(e->data)->type;
278 
279                 if (type_is_ancestor(target_type, t)) {
280                     break;
281                 }
282             }
283 
284             if (e) {
285                 continue;
286             }
287 
288             type_initialize_interface(ti, t, t);
289         }
290     }
291 
292     ti->class->type = ti;
293 
294     while (parent) {
295         if (parent->class_base_init) {
296             parent->class_base_init(ti->class, ti->class_data);
297         }
298         parent = type_get_parent(parent);
299     }
300 
301     if (ti->class_init) {
302         ti->class_init(ti->class, ti->class_data);
303     }
304 }
305 
306 static void object_init_with_type(Object *obj, TypeImpl *ti)
307 {
308     if (type_has_parent(ti)) {
309         object_init_with_type(obj, type_get_parent(ti));
310     }
311 
312     if (ti->instance_init) {
313         ti->instance_init(obj);
314     }
315 }
316 
317 static void object_post_init_with_type(Object *obj, TypeImpl *ti)
318 {
319     if (ti->instance_post_init) {
320         ti->instance_post_init(obj);
321     }
322 
323     if (type_has_parent(ti)) {
324         object_post_init_with_type(obj, type_get_parent(ti));
325     }
326 }
327 
328 void object_initialize_with_type(void *data, size_t size, TypeImpl *type)
329 {
330     Object *obj = data;
331 
332     g_assert(type != NULL);
333     type_initialize(type);
334 
335     g_assert(type->instance_size >= sizeof(Object));
336     g_assert(type->abstract == false);
337     g_assert(size >= type->instance_size);
338 
339     memset(obj, 0, type->instance_size);
340     obj->class = type->class;
341     object_ref(obj);
342     QTAILQ_INIT(&obj->properties);
343     object_init_with_type(obj, type);
344     object_post_init_with_type(obj, type);
345 }
346 
347 void object_initialize(void *data, size_t size, const char *typename)
348 {
349     TypeImpl *type = type_get_by_name(typename);
350 
351     object_initialize_with_type(data, size, type);
352 }
353 
354 static inline bool object_property_is_child(ObjectProperty *prop)
355 {
356     return strstart(prop->type, "child<", NULL);
357 }
358 
359 static inline bool object_property_is_link(ObjectProperty *prop)
360 {
361     return strstart(prop->type, "link<", NULL);
362 }
363 
364 static void object_property_del_all(Object *obj)
365 {
366     while (!QTAILQ_EMPTY(&obj->properties)) {
367         ObjectProperty *prop = QTAILQ_FIRST(&obj->properties);
368 
369         QTAILQ_REMOVE(&obj->properties, prop, node);
370 
371         if (prop->release) {
372             prop->release(obj, prop->name, prop->opaque);
373         }
374 
375         g_free(prop->name);
376         g_free(prop->type);
377         g_free(prop);
378     }
379 }
380 
381 static void object_property_del_child(Object *obj, Object *child, Error **errp)
382 {
383     ObjectProperty *prop;
384 
385     QTAILQ_FOREACH(prop, &obj->properties, node) {
386         if (object_property_is_child(prop) && prop->opaque == child) {
387             object_property_del(obj, prop->name, errp);
388             break;
389         }
390     }
391 }
392 
393 void object_unparent(Object *obj)
394 {
395     if (!obj->parent) {
396         return;
397     }
398 
399     object_ref(obj);
400     if (obj->class->unparent) {
401         (obj->class->unparent)(obj);
402     }
403     if (obj->parent) {
404         object_property_del_child(obj->parent, obj, NULL);
405         obj->parent = NULL;
406     }
407     object_unref(obj);
408 }
409 
410 static void object_deinit(Object *obj, TypeImpl *type)
411 {
412     if (type->instance_finalize) {
413         type->instance_finalize(obj);
414     }
415 
416     if (type_has_parent(type)) {
417         object_deinit(obj, type_get_parent(type));
418     }
419 }
420 
421 static void object_finalize(void *data)
422 {
423     Object *obj = data;
424     TypeImpl *ti = obj->class->type;
425 
426     object_deinit(obj, ti);
427     object_property_del_all(obj);
428 
429     g_assert(obj->ref == 0);
430     if (obj->free) {
431         obj->free(obj);
432     }
433 }
434 
435 Object *object_new_with_type(Type type)
436 {
437     Object *obj;
438 
439     g_assert(type != NULL);
440     type_initialize(type);
441 
442     obj = g_malloc(type->instance_size);
443     object_initialize_with_type(obj, type->instance_size, type);
444     obj->free = g_free;
445 
446     return obj;
447 }
448 
449 Object *object_new(const char *typename)
450 {
451     TypeImpl *ti = type_get_by_name(typename);
452 
453     return object_new_with_type(ti);
454 }
455 
456 Object *object_dynamic_cast(Object *obj, const char *typename)
457 {
458     if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
459         return obj;
460     }
461 
462     return NULL;
463 }
464 
465 Object *object_dynamic_cast_assert(Object *obj, const char *typename,
466                                    const char *file, int line, const char *func)
467 {
468     trace_object_dynamic_cast_assert(obj ? obj->class->type->name : "(null)",
469                                      typename, file, line, func);
470 
471 #ifdef CONFIG_QOM_CAST_DEBUG
472     int i;
473     Object *inst;
474 
475     for (i = 0; obj && i < OBJECT_CLASS_CAST_CACHE; i++) {
476         if (obj->class->object_cast_cache[i] == typename) {
477             goto out;
478         }
479     }
480 
481     inst = object_dynamic_cast(obj, typename);
482 
483     if (!inst && obj) {
484         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
485                 file, line, func, obj, typename);
486         abort();
487     }
488 
489     assert(obj == inst);
490 
491     if (obj && obj == inst) {
492         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
493             obj->class->object_cast_cache[i - 1] =
494                     obj->class->object_cast_cache[i];
495         }
496         obj->class->object_cast_cache[i - 1] = typename;
497     }
498 
499 out:
500 #endif
501     return obj;
502 }
503 
504 ObjectClass *object_class_dynamic_cast(ObjectClass *class,
505                                        const char *typename)
506 {
507     ObjectClass *ret = NULL;
508     TypeImpl *target_type;
509     TypeImpl *type;
510 
511     if (!class) {
512         return NULL;
513     }
514 
515     /* A simple fast path that can trigger a lot for leaf classes.  */
516     type = class->type;
517     if (type->name == typename) {
518         return class;
519     }
520 
521     target_type = type_get_by_name(typename);
522     if (!target_type) {
523         /* target class type unknown, so fail the cast */
524         return NULL;
525     }
526 
527     if (type->class->interfaces &&
528             type_is_ancestor(target_type, type_interface)) {
529         int found = 0;
530         GSList *i;
531 
532         for (i = class->interfaces; i; i = i->next) {
533             ObjectClass *target_class = i->data;
534 
535             if (type_is_ancestor(target_class->type, target_type)) {
536                 ret = target_class;
537                 found++;
538             }
539          }
540 
541         /* The match was ambiguous, don't allow a cast */
542         if (found > 1) {
543             ret = NULL;
544         }
545     } else if (type_is_ancestor(type, target_type)) {
546         ret = class;
547     }
548 
549     return ret;
550 }
551 
552 ObjectClass *object_class_dynamic_cast_assert(ObjectClass *class,
553                                               const char *typename,
554                                               const char *file, int line,
555                                               const char *func)
556 {
557     ObjectClass *ret;
558 
559     trace_object_class_dynamic_cast_assert(class ? class->type->name : "(null)",
560                                            typename, file, line, func);
561 
562 #ifdef CONFIG_QOM_CAST_DEBUG
563     int i;
564 
565     for (i = 0; class && i < OBJECT_CLASS_CAST_CACHE; i++) {
566         if (class->class_cast_cache[i] == typename) {
567             ret = class;
568             goto out;
569         }
570     }
571 #else
572     if (!class || !class->interfaces) {
573         return class;
574     }
575 #endif
576 
577     ret = object_class_dynamic_cast(class, typename);
578     if (!ret && class) {
579         fprintf(stderr, "%s:%d:%s: Object %p is not an instance of type %s\n",
580                 file, line, func, class, typename);
581         abort();
582     }
583 
584 #ifdef CONFIG_QOM_CAST_DEBUG
585     if (class && ret == class) {
586         for (i = 1; i < OBJECT_CLASS_CAST_CACHE; i++) {
587             class->class_cast_cache[i - 1] = class->class_cast_cache[i];
588         }
589         class->class_cast_cache[i - 1] = typename;
590     }
591 out:
592 #endif
593     return ret;
594 }
595 
596 const char *object_get_typename(Object *obj)
597 {
598     return obj->class->type->name;
599 }
600 
601 ObjectClass *object_get_class(Object *obj)
602 {
603     return obj->class;
604 }
605 
606 bool object_class_is_abstract(ObjectClass *klass)
607 {
608     return klass->type->abstract;
609 }
610 
611 const char *object_class_get_name(ObjectClass *klass)
612 {
613     return klass->type->name;
614 }
615 
616 ObjectClass *object_class_by_name(const char *typename)
617 {
618     TypeImpl *type = type_get_by_name(typename);
619 
620     if (!type) {
621         return NULL;
622     }
623 
624     type_initialize(type);
625 
626     return type->class;
627 }
628 
629 ObjectClass *object_class_get_parent(ObjectClass *class)
630 {
631     TypeImpl *type = type_get_parent(class->type);
632 
633     if (!type) {
634         return NULL;
635     }
636 
637     type_initialize(type);
638 
639     return type->class;
640 }
641 
642 typedef struct OCFData
643 {
644     void (*fn)(ObjectClass *klass, void *opaque);
645     const char *implements_type;
646     bool include_abstract;
647     void *opaque;
648 } OCFData;
649 
650 static void object_class_foreach_tramp(gpointer key, gpointer value,
651                                        gpointer opaque)
652 {
653     OCFData *data = opaque;
654     TypeImpl *type = value;
655     ObjectClass *k;
656 
657     type_initialize(type);
658     k = type->class;
659 
660     if (!data->include_abstract && type->abstract) {
661         return;
662     }
663 
664     if (data->implements_type &&
665         !object_class_dynamic_cast(k, data->implements_type)) {
666         return;
667     }
668 
669     data->fn(k, data->opaque);
670 }
671 
672 void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
673                           const char *implements_type, bool include_abstract,
674                           void *opaque)
675 {
676     OCFData data = { fn, implements_type, include_abstract, opaque };
677 
678     enumerating_types = true;
679     g_hash_table_foreach(type_table_get(), object_class_foreach_tramp, &data);
680     enumerating_types = false;
681 }
682 
683 int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
684                          void *opaque)
685 {
686     ObjectProperty *prop;
687     int ret = 0;
688 
689     QTAILQ_FOREACH(prop, &obj->properties, node) {
690         if (object_property_is_child(prop)) {
691             ret = fn(prop->opaque, opaque);
692             if (ret != 0) {
693                 break;
694             }
695         }
696     }
697     return ret;
698 }
699 
700 static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
701 {
702     GSList **list = opaque;
703 
704     *list = g_slist_prepend(*list, klass);
705 }
706 
707 GSList *object_class_get_list(const char *implements_type,
708                               bool include_abstract)
709 {
710     GSList *list = NULL;
711 
712     object_class_foreach(object_class_get_list_tramp,
713                          implements_type, include_abstract, &list);
714     return list;
715 }
716 
717 void object_ref(Object *obj)
718 {
719      atomic_inc(&obj->ref);
720 }
721 
722 void object_unref(Object *obj)
723 {
724     g_assert(obj->ref > 0);
725 
726     /* parent always holds a reference to its children */
727     if (atomic_fetch_dec(&obj->ref) == 1) {
728         object_finalize(obj);
729     }
730 }
731 
732 void object_property_add(Object *obj, const char *name, const char *type,
733                          ObjectPropertyAccessor *get,
734                          ObjectPropertyAccessor *set,
735                          ObjectPropertyRelease *release,
736                          void *opaque, Error **errp)
737 {
738     ObjectProperty *prop;
739 
740     QTAILQ_FOREACH(prop, &obj->properties, node) {
741         if (strcmp(prop->name, name) == 0) {
742             error_setg(errp, "attempt to add duplicate property '%s'"
743                        " to object (type '%s')", name,
744                        object_get_typename(obj));
745             return;
746         }
747     }
748 
749     prop = g_malloc0(sizeof(*prop));
750 
751     prop->name = g_strdup(name);
752     prop->type = g_strdup(type);
753 
754     prop->get = get;
755     prop->set = set;
756     prop->release = release;
757     prop->opaque = opaque;
758 
759     QTAILQ_INSERT_TAIL(&obj->properties, prop, node);
760 }
761 
762 ObjectProperty *object_property_find(Object *obj, const char *name,
763                                      Error **errp)
764 {
765     ObjectProperty *prop;
766 
767     QTAILQ_FOREACH(prop, &obj->properties, node) {
768         if (strcmp(prop->name, name) == 0) {
769             return prop;
770         }
771     }
772 
773     error_setg(errp, "Property '.%s' not found", name);
774     return NULL;
775 }
776 
777 void object_property_del(Object *obj, const char *name, Error **errp)
778 {
779     ObjectProperty *prop = object_property_find(obj, name, errp);
780     if (prop == NULL) {
781         return;
782     }
783 
784     if (prop->release) {
785         prop->release(obj, name, prop->opaque);
786     }
787 
788     QTAILQ_REMOVE(&obj->properties, prop, node);
789 
790     g_free(prop->name);
791     g_free(prop->type);
792     g_free(prop);
793 }
794 
795 void object_property_get(Object *obj, Visitor *v, const char *name,
796                          Error **errp)
797 {
798     ObjectProperty *prop = object_property_find(obj, name, errp);
799     if (prop == NULL) {
800         return;
801     }
802 
803     if (!prop->get) {
804         error_set(errp, QERR_PERMISSION_DENIED);
805     } else {
806         prop->get(obj, v, prop->opaque, name, errp);
807     }
808 }
809 
810 void object_property_set(Object *obj, Visitor *v, const char *name,
811                          Error **errp)
812 {
813     ObjectProperty *prop = object_property_find(obj, name, errp);
814     if (prop == NULL) {
815         return;
816     }
817 
818     if (!prop->set) {
819         error_set(errp, QERR_PERMISSION_DENIED);
820     } else {
821         prop->set(obj, v, prop->opaque, name, errp);
822     }
823 }
824 
825 void object_property_set_str(Object *obj, const char *value,
826                              const char *name, Error **errp)
827 {
828     QString *qstr = qstring_from_str(value);
829     object_property_set_qobject(obj, QOBJECT(qstr), name, errp);
830 
831     QDECREF(qstr);
832 }
833 
834 char *object_property_get_str(Object *obj, const char *name,
835                               Error **errp)
836 {
837     QObject *ret = object_property_get_qobject(obj, name, errp);
838     QString *qstring;
839     char *retval;
840 
841     if (!ret) {
842         return NULL;
843     }
844     qstring = qobject_to_qstring(ret);
845     if (!qstring) {
846         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "string");
847         retval = NULL;
848     } else {
849         retval = g_strdup(qstring_get_str(qstring));
850     }
851 
852     QDECREF(qstring);
853     return retval;
854 }
855 
856 void object_property_set_link(Object *obj, Object *value,
857                               const char *name, Error **errp)
858 {
859     gchar *path = object_get_canonical_path(value);
860     object_property_set_str(obj, path, name, errp);
861     g_free(path);
862 }
863 
864 Object *object_property_get_link(Object *obj, const char *name,
865                                  Error **errp)
866 {
867     char *str = object_property_get_str(obj, name, errp);
868     Object *target = NULL;
869 
870     if (str && *str) {
871         target = object_resolve_path(str, NULL);
872         if (!target) {
873             error_set(errp, QERR_DEVICE_NOT_FOUND, str);
874         }
875     }
876 
877     g_free(str);
878     return target;
879 }
880 
881 void object_property_set_bool(Object *obj, bool value,
882                               const char *name, Error **errp)
883 {
884     QBool *qbool = qbool_from_int(value);
885     object_property_set_qobject(obj, QOBJECT(qbool), name, errp);
886 
887     QDECREF(qbool);
888 }
889 
890 bool object_property_get_bool(Object *obj, const char *name,
891                               Error **errp)
892 {
893     QObject *ret = object_property_get_qobject(obj, name, errp);
894     QBool *qbool;
895     bool retval;
896 
897     if (!ret) {
898         return false;
899     }
900     qbool = qobject_to_qbool(ret);
901     if (!qbool) {
902         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "boolean");
903         retval = false;
904     } else {
905         retval = qbool_get_int(qbool);
906     }
907 
908     QDECREF(qbool);
909     return retval;
910 }
911 
912 void object_property_set_int(Object *obj, int64_t value,
913                              const char *name, Error **errp)
914 {
915     QInt *qint = qint_from_int(value);
916     object_property_set_qobject(obj, QOBJECT(qint), name, errp);
917 
918     QDECREF(qint);
919 }
920 
921 int64_t object_property_get_int(Object *obj, const char *name,
922                                 Error **errp)
923 {
924     QObject *ret = object_property_get_qobject(obj, name, errp);
925     QInt *qint;
926     int64_t retval;
927 
928     if (!ret) {
929         return -1;
930     }
931     qint = qobject_to_qint(ret);
932     if (!qint) {
933         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, "int");
934         retval = -1;
935     } else {
936         retval = qint_get_int(qint);
937     }
938 
939     QDECREF(qint);
940     return retval;
941 }
942 
943 int object_property_get_enum(Object *obj, const char *name,
944                              const char *strings[], Error **errp)
945 {
946     StringOutputVisitor *sov;
947     StringInputVisitor *siv;
948     int ret;
949 
950     sov = string_output_visitor_new(false);
951     object_property_get(obj, string_output_get_visitor(sov), name, errp);
952     siv = string_input_visitor_new(string_output_get_string(sov));
953     string_output_visitor_cleanup(sov);
954     visit_type_enum(string_input_get_visitor(siv),
955                     &ret, strings, NULL, name, errp);
956     string_input_visitor_cleanup(siv);
957 
958     return ret;
959 }
960 
961 void object_property_get_uint16List(Object *obj, const char *name,
962                                     uint16List **list, Error **errp)
963 {
964     StringOutputVisitor *ov;
965     StringInputVisitor *iv;
966 
967     ov = string_output_visitor_new(false);
968     object_property_get(obj, string_output_get_visitor(ov),
969                         name, errp);
970     iv = string_input_visitor_new(string_output_get_string(ov));
971     visit_type_uint16List(string_input_get_visitor(iv),
972                           list, NULL, errp);
973     string_output_visitor_cleanup(ov);
974     string_input_visitor_cleanup(iv);
975 }
976 
977 void object_property_parse(Object *obj, const char *string,
978                            const char *name, Error **errp)
979 {
980     StringInputVisitor *mi;
981     mi = string_input_visitor_new(string);
982     object_property_set(obj, string_input_get_visitor(mi), name, errp);
983 
984     string_input_visitor_cleanup(mi);
985 }
986 
987 char *object_property_print(Object *obj, const char *name, bool human,
988                             Error **errp)
989 {
990     StringOutputVisitor *mo;
991     char *string;
992 
993     mo = string_output_visitor_new(human);
994     object_property_get(obj, string_output_get_visitor(mo), name, errp);
995     string = string_output_get_string(mo);
996     string_output_visitor_cleanup(mo);
997     return string;
998 }
999 
1000 const char *object_property_get_type(Object *obj, const char *name, Error **errp)
1001 {
1002     ObjectProperty *prop = object_property_find(obj, name, errp);
1003     if (prop == NULL) {
1004         return NULL;
1005     }
1006 
1007     return prop->type;
1008 }
1009 
1010 Object *object_get_root(void)
1011 {
1012     static Object *root;
1013 
1014     if (!root) {
1015         root = object_new("container");
1016     }
1017 
1018     return root;
1019 }
1020 
1021 static void object_get_child_property(Object *obj, Visitor *v, void *opaque,
1022                                       const char *name, Error **errp)
1023 {
1024     Object *child = opaque;
1025     gchar *path;
1026 
1027     path = object_get_canonical_path(child);
1028     visit_type_str(v, &path, name, errp);
1029     g_free(path);
1030 }
1031 
1032 static void object_finalize_child_property(Object *obj, const char *name,
1033                                            void *opaque)
1034 {
1035     Object *child = opaque;
1036 
1037     object_unref(child);
1038 }
1039 
1040 void object_property_add_child(Object *obj, const char *name,
1041                                Object *child, Error **errp)
1042 {
1043     Error *local_err = NULL;
1044     gchar *type;
1045 
1046     type = g_strdup_printf("child<%s>", object_get_typename(OBJECT(child)));
1047 
1048     object_property_add(obj, name, type, object_get_child_property, NULL,
1049                         object_finalize_child_property, child, &local_err);
1050     if (local_err) {
1051         error_propagate(errp, local_err);
1052         goto out;
1053     }
1054     object_ref(child);
1055     g_assert(child->parent == NULL);
1056     child->parent = obj;
1057 
1058 out:
1059     g_free(type);
1060 }
1061 
1062 void object_property_allow_set_link(Object *obj, const char *name,
1063                                     Object *val, Error **errp)
1064 {
1065     /* Allow the link to be set, always */
1066 }
1067 
1068 typedef struct {
1069     Object **child;
1070     void (*check)(Object *, const char *, Object *, Error **);
1071     ObjectPropertyLinkFlags flags;
1072 } LinkProperty;
1073 
1074 static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
1075                                      const char *name, Error **errp)
1076 {
1077     LinkProperty *lprop = opaque;
1078     Object **child = lprop->child;
1079     gchar *path;
1080 
1081     if (*child) {
1082         path = object_get_canonical_path(*child);
1083         visit_type_str(v, &path, name, errp);
1084         g_free(path);
1085     } else {
1086         path = (gchar *)"";
1087         visit_type_str(v, &path, name, errp);
1088     }
1089 }
1090 
1091 /*
1092  * object_resolve_link:
1093  *
1094  * Lookup an object and ensure its type matches the link property type.  This
1095  * is similar to object_resolve_path() except type verification against the
1096  * link property is performed.
1097  *
1098  * Returns: The matched object or NULL on path lookup failures.
1099  */
1100 static Object *object_resolve_link(Object *obj, const char *name,
1101                                    const char *path, Error **errp)
1102 {
1103     const char *type;
1104     gchar *target_type;
1105     bool ambiguous = false;
1106     Object *target;
1107 
1108     /* Go from link<FOO> to FOO.  */
1109     type = object_property_get_type(obj, name, NULL);
1110     target_type = g_strndup(&type[5], strlen(type) - 6);
1111     target = object_resolve_path_type(path, target_type, &ambiguous);
1112 
1113     if (ambiguous) {
1114         error_set(errp, ERROR_CLASS_GENERIC_ERROR,
1115                   "Path '%s' does not uniquely identify an object", path);
1116     } else if (!target) {
1117         target = object_resolve_path(path, &ambiguous);
1118         if (target || ambiguous) {
1119             error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
1120         } else {
1121             error_set(errp, QERR_DEVICE_NOT_FOUND, path);
1122         }
1123         target = NULL;
1124     }
1125     g_free(target_type);
1126 
1127     return target;
1128 }
1129 
1130 static void object_set_link_property(Object *obj, Visitor *v, void *opaque,
1131                                      const char *name, Error **errp)
1132 {
1133     Error *local_err = NULL;
1134     LinkProperty *prop = opaque;
1135     Object **child = prop->child;
1136     Object *old_target = *child;
1137     Object *new_target = NULL;
1138     char *path = NULL;
1139 
1140     visit_type_str(v, &path, name, &local_err);
1141 
1142     if (!local_err && strcmp(path, "") != 0) {
1143         new_target = object_resolve_link(obj, name, path, &local_err);
1144     }
1145 
1146     g_free(path);
1147     if (local_err) {
1148         error_propagate(errp, local_err);
1149         return;
1150     }
1151 
1152     prop->check(obj, name, new_target, &local_err);
1153     if (local_err) {
1154         error_propagate(errp, local_err);
1155         return;
1156     }
1157 
1158     if (new_target) {
1159         object_ref(new_target);
1160     }
1161     *child = new_target;
1162     if (old_target != NULL) {
1163         object_unref(old_target);
1164     }
1165 }
1166 
1167 static void object_release_link_property(Object *obj, const char *name,
1168                                          void *opaque)
1169 {
1170     LinkProperty *prop = opaque;
1171 
1172     if ((prop->flags & OBJ_PROP_LINK_UNREF_ON_RELEASE) && *prop->child) {
1173         object_unref(*prop->child);
1174     }
1175     g_free(prop);
1176 }
1177 
1178 void object_property_add_link(Object *obj, const char *name,
1179                               const char *type, Object **child,
1180                               void (*check)(Object *, const char *,
1181                                             Object *, Error **),
1182                               ObjectPropertyLinkFlags flags,
1183                               Error **errp)
1184 {
1185     Error *local_err = NULL;
1186     LinkProperty *prop = g_malloc(sizeof(*prop));
1187     gchar *full_type;
1188 
1189     prop->child = child;
1190     prop->check = check;
1191     prop->flags = flags;
1192 
1193     full_type = g_strdup_printf("link<%s>", type);
1194 
1195     object_property_add(obj, name, full_type,
1196                         object_get_link_property,
1197                         check ? object_set_link_property : NULL,
1198                         object_release_link_property,
1199                         prop,
1200                         &local_err);
1201     if (local_err) {
1202         error_propagate(errp, local_err);
1203         g_free(prop);
1204     }
1205 
1206     g_free(full_type);
1207 }
1208 
1209 gchar *object_get_canonical_path_component(Object *obj)
1210 {
1211     ObjectProperty *prop = NULL;
1212 
1213     g_assert(obj);
1214     g_assert(obj->parent != NULL);
1215 
1216     QTAILQ_FOREACH(prop, &obj->parent->properties, node) {
1217         if (!object_property_is_child(prop)) {
1218             continue;
1219         }
1220 
1221         if (prop->opaque == obj) {
1222             return g_strdup(prop->name);
1223         }
1224     }
1225 
1226     /* obj had a parent but was not a child, should never happen */
1227     g_assert_not_reached();
1228     return NULL;
1229 }
1230 
1231 gchar *object_get_canonical_path(Object *obj)
1232 {
1233     Object *root = object_get_root();
1234     char *newpath, *path = NULL;
1235 
1236     while (obj != root) {
1237         char *component = object_get_canonical_path_component(obj);
1238 
1239         if (path) {
1240             newpath = g_strdup_printf("%s/%s", component, path);
1241             g_free(component);
1242             g_free(path);
1243             path = newpath;
1244         } else {
1245             path = component;
1246         }
1247 
1248         obj = obj->parent;
1249     }
1250 
1251     newpath = g_strdup_printf("/%s", path ? path : "");
1252     g_free(path);
1253 
1254     return newpath;
1255 }
1256 
1257 Object *object_resolve_path_component(Object *parent, const gchar *part)
1258 {
1259     ObjectProperty *prop = object_property_find(parent, part, NULL);
1260     if (prop == NULL) {
1261         return NULL;
1262     }
1263 
1264     if (object_property_is_link(prop)) {
1265         LinkProperty *lprop = prop->opaque;
1266         return *lprop->child;
1267     } else if (object_property_is_child(prop)) {
1268         return prop->opaque;
1269     } else {
1270         return NULL;
1271     }
1272 }
1273 
1274 static Object *object_resolve_abs_path(Object *parent,
1275                                           gchar **parts,
1276                                           const char *typename,
1277                                           int index)
1278 {
1279     Object *child;
1280 
1281     if (parts[index] == NULL) {
1282         return object_dynamic_cast(parent, typename);
1283     }
1284 
1285     if (strcmp(parts[index], "") == 0) {
1286         return object_resolve_abs_path(parent, parts, typename, index + 1);
1287     }
1288 
1289     child = object_resolve_path_component(parent, parts[index]);
1290     if (!child) {
1291         return NULL;
1292     }
1293 
1294     return object_resolve_abs_path(child, parts, typename, index + 1);
1295 }
1296 
1297 static Object *object_resolve_partial_path(Object *parent,
1298                                               gchar **parts,
1299                                               const char *typename,
1300                                               bool *ambiguous)
1301 {
1302     Object *obj;
1303     ObjectProperty *prop;
1304 
1305     obj = object_resolve_abs_path(parent, parts, typename, 0);
1306 
1307     QTAILQ_FOREACH(prop, &parent->properties, node) {
1308         Object *found;
1309 
1310         if (!object_property_is_child(prop)) {
1311             continue;
1312         }
1313 
1314         found = object_resolve_partial_path(prop->opaque, parts,
1315                                             typename, ambiguous);
1316         if (found) {
1317             if (obj) {
1318                 if (ambiguous) {
1319                     *ambiguous = true;
1320                 }
1321                 return NULL;
1322             }
1323             obj = found;
1324         }
1325 
1326         if (ambiguous && *ambiguous) {
1327             return NULL;
1328         }
1329     }
1330 
1331     return obj;
1332 }
1333 
1334 Object *object_resolve_path_type(const char *path, const char *typename,
1335                                  bool *ambiguous)
1336 {
1337     Object *obj;
1338     gchar **parts;
1339 
1340     parts = g_strsplit(path, "/", 0);
1341     assert(parts);
1342 
1343     if (parts[0] == NULL || strcmp(parts[0], "") != 0) {
1344         if (ambiguous) {
1345             *ambiguous = false;
1346         }
1347         obj = object_resolve_partial_path(object_get_root(), parts,
1348                                           typename, ambiguous);
1349     } else {
1350         obj = object_resolve_abs_path(object_get_root(), parts, typename, 1);
1351     }
1352 
1353     g_strfreev(parts);
1354 
1355     return obj;
1356 }
1357 
1358 Object *object_resolve_path(const char *path, bool *ambiguous)
1359 {
1360     return object_resolve_path_type(path, TYPE_OBJECT, ambiguous);
1361 }
1362 
1363 typedef struct StringProperty
1364 {
1365     char *(*get)(Object *, Error **);
1366     void (*set)(Object *, const char *, Error **);
1367 } StringProperty;
1368 
1369 static void property_get_str(Object *obj, Visitor *v, void *opaque,
1370                              const char *name, Error **errp)
1371 {
1372     StringProperty *prop = opaque;
1373     char *value;
1374 
1375     value = prop->get(obj, errp);
1376     if (value) {
1377         visit_type_str(v, &value, name, errp);
1378         g_free(value);
1379     }
1380 }
1381 
1382 static void property_set_str(Object *obj, Visitor *v, void *opaque,
1383                              const char *name, Error **errp)
1384 {
1385     StringProperty *prop = opaque;
1386     char *value;
1387     Error *local_err = NULL;
1388 
1389     visit_type_str(v, &value, name, &local_err);
1390     if (local_err) {
1391         error_propagate(errp, local_err);
1392         return;
1393     }
1394 
1395     prop->set(obj, value, errp);
1396     g_free(value);
1397 }
1398 
1399 static void property_release_str(Object *obj, const char *name,
1400                                  void *opaque)
1401 {
1402     StringProperty *prop = opaque;
1403     g_free(prop);
1404 }
1405 
1406 void object_property_add_str(Object *obj, const char *name,
1407                            char *(*get)(Object *, Error **),
1408                            void (*set)(Object *, const char *, Error **),
1409                            Error **errp)
1410 {
1411     Error *local_err = NULL;
1412     StringProperty *prop = g_malloc0(sizeof(*prop));
1413 
1414     prop->get = get;
1415     prop->set = set;
1416 
1417     object_property_add(obj, name, "string",
1418                         get ? property_get_str : NULL,
1419                         set ? property_set_str : NULL,
1420                         property_release_str,
1421                         prop, &local_err);
1422     if (local_err) {
1423         error_propagate(errp, local_err);
1424         g_free(prop);
1425     }
1426 }
1427 
1428 typedef struct BoolProperty
1429 {
1430     bool (*get)(Object *, Error **);
1431     void (*set)(Object *, bool, Error **);
1432 } BoolProperty;
1433 
1434 static void property_get_bool(Object *obj, Visitor *v, void *opaque,
1435                               const char *name, Error **errp)
1436 {
1437     BoolProperty *prop = opaque;
1438     bool value;
1439 
1440     value = prop->get(obj, errp);
1441     visit_type_bool(v, &value, name, errp);
1442 }
1443 
1444 static void property_set_bool(Object *obj, Visitor *v, void *opaque,
1445                               const char *name, Error **errp)
1446 {
1447     BoolProperty *prop = opaque;
1448     bool value;
1449     Error *local_err = NULL;
1450 
1451     visit_type_bool(v, &value, name, &local_err);
1452     if (local_err) {
1453         error_propagate(errp, local_err);
1454         return;
1455     }
1456 
1457     prop->set(obj, value, errp);
1458 }
1459 
1460 static void property_release_bool(Object *obj, const char *name,
1461                                   void *opaque)
1462 {
1463     BoolProperty *prop = opaque;
1464     g_free(prop);
1465 }
1466 
1467 void object_property_add_bool(Object *obj, const char *name,
1468                               bool (*get)(Object *, Error **),
1469                               void (*set)(Object *, bool, Error **),
1470                               Error **errp)
1471 {
1472     Error *local_err = NULL;
1473     BoolProperty *prop = g_malloc0(sizeof(*prop));
1474 
1475     prop->get = get;
1476     prop->set = set;
1477 
1478     object_property_add(obj, name, "bool",
1479                         get ? property_get_bool : NULL,
1480                         set ? property_set_bool : NULL,
1481                         property_release_bool,
1482                         prop, &local_err);
1483     if (local_err) {
1484         error_propagate(errp, local_err);
1485         g_free(prop);
1486     }
1487 }
1488 
1489 static char *qdev_get_type(Object *obj, Error **errp)
1490 {
1491     return g_strdup(object_get_typename(obj));
1492 }
1493 
1494 static void property_get_uint8_ptr(Object *obj, Visitor *v,
1495                                    void *opaque, const char *name,
1496                                    Error **errp)
1497 {
1498     uint8_t value = *(uint8_t *)opaque;
1499     visit_type_uint8(v, &value, name, errp);
1500 }
1501 
1502 static void property_get_uint16_ptr(Object *obj, Visitor *v,
1503                                    void *opaque, const char *name,
1504                                    Error **errp)
1505 {
1506     uint16_t value = *(uint16_t *)opaque;
1507     visit_type_uint16(v, &value, name, errp);
1508 }
1509 
1510 static void property_get_uint32_ptr(Object *obj, Visitor *v,
1511                                    void *opaque, const char *name,
1512                                    Error **errp)
1513 {
1514     uint32_t value = *(uint32_t *)opaque;
1515     visit_type_uint32(v, &value, name, errp);
1516 }
1517 
1518 static void property_get_uint64_ptr(Object *obj, Visitor *v,
1519                                    void *opaque, const char *name,
1520                                    Error **errp)
1521 {
1522     uint64_t value = *(uint64_t *)opaque;
1523     visit_type_uint64(v, &value, name, errp);
1524 }
1525 
1526 void object_property_add_uint8_ptr(Object *obj, const char *name,
1527                                    const uint8_t *v, Error **errp)
1528 {
1529     object_property_add(obj, name, "uint8", property_get_uint8_ptr,
1530                         NULL, NULL, (void *)v, errp);
1531 }
1532 
1533 void object_property_add_uint16_ptr(Object *obj, const char *name,
1534                                     const uint16_t *v, Error **errp)
1535 {
1536     object_property_add(obj, name, "uint16", property_get_uint16_ptr,
1537                         NULL, NULL, (void *)v, errp);
1538 }
1539 
1540 void object_property_add_uint32_ptr(Object *obj, const char *name,
1541                                     const uint32_t *v, Error **errp)
1542 {
1543     object_property_add(obj, name, "uint32", property_get_uint32_ptr,
1544                         NULL, NULL, (void *)v, errp);
1545 }
1546 
1547 void object_property_add_uint64_ptr(Object *obj, const char *name,
1548                                     const uint64_t *v, Error **errp)
1549 {
1550     object_property_add(obj, name, "uint64", property_get_uint64_ptr,
1551                         NULL, NULL, (void *)v, errp);
1552 }
1553 
1554 static void object_instance_init(Object *obj)
1555 {
1556     object_property_add_str(obj, "type", qdev_get_type, NULL, NULL);
1557 }
1558 
1559 static void register_types(void)
1560 {
1561     static TypeInfo interface_info = {
1562         .name = TYPE_INTERFACE,
1563         .class_size = sizeof(InterfaceClass),
1564         .abstract = true,
1565     };
1566 
1567     static TypeInfo object_info = {
1568         .name = TYPE_OBJECT,
1569         .instance_size = sizeof(Object),
1570         .instance_init = object_instance_init,
1571         .abstract = true,
1572     };
1573 
1574     type_interface = type_register_internal(&interface_info);
1575     type_register_internal(&object_info);
1576 }
1577 
1578 type_init(register_types)
1579