xref: /qemu/qapi/qobject-input-visitor.c (revision 423f7cf2) 
1 /*
2  * Input Visitor
3  *
4  * Copyright (C) 2012-2016 Red Hat, Inc.
5  * Copyright IBM, Corp. 2011
6  *
7  * Authors:
8  *  Anthony Liguori   <aliguori@us.ibm.com>
9  *
10  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
11  * See the COPYING.LIB file in the top-level directory.
12  *
13  */
14 
15 #include "qemu/osdep.h"
16 #include "qapi/error.h"
17 #include "qapi/qobject-input-visitor.h"
18 #include "qapi/visitor-impl.h"
19 #include "qemu/queue.h"
20 #include "qemu-common.h"
21 #include "qapi/qmp/types.h"
22 #include "qapi/qmp/qerror.h"
23 
24 #define QIV_STACK_SIZE 1024
25 
26 typedef struct StackObject
27 {
28     QObject *obj; /* Object being visited */
29     void *qapi; /* sanity check that caller uses same pointer */
30 
31     GHashTable *h;           /* If obj is dict: unvisited keys */
32     const QListEntry *entry; /* If obj is list: unvisited tail */
33 
34     QSLIST_ENTRY(StackObject) node;
35 } StackObject;
36 
37 struct QObjectInputVisitor
38 {
39     Visitor visitor;
40 
41     /* Root of visit at visitor creation. */
42     QObject *root;
43 
44     /* Stack of objects being visited (all entries will be either
45      * QDict or QList). */
46     QSLIST_HEAD(, StackObject) stack;
47 
48     /* True to reject parse in visit_end_struct() if unvisited keys remain. */
49     bool strict;
50 };
51 
52 static QObjectInputVisitor *to_qiv(Visitor *v)
53 {
54     return container_of(v, QObjectInputVisitor, visitor);
55 }
56 
57 static QObject *qobject_input_get_object(QObjectInputVisitor *qiv,
58                                          const char *name,
59                                          bool consume, Error **errp)
60 {
61     StackObject *tos;
62     QObject *qobj;
63     QObject *ret;
64 
65     if (QSLIST_EMPTY(&qiv->stack)) {
66         /* Starting at root, name is ignored. */
67         assert(qiv->root);
68         return qiv->root;
69     }
70 
71     /* We are in a container; find the next element. */
72     tos = QSLIST_FIRST(&qiv->stack);
73     qobj = tos->obj;
74     assert(qobj);
75 
76     if (qobject_type(qobj) == QTYPE_QDICT) {
77         assert(name);
78         ret = qdict_get(qobject_to_qdict(qobj), name);
79         if (tos->h && consume && ret) {
80             bool removed = g_hash_table_remove(tos->h, name);
81             assert(removed);
82         }
83         if (!ret) {
84             error_setg(errp, QERR_MISSING_PARAMETER, name);
85         }
86     } else {
87         assert(qobject_type(qobj) == QTYPE_QLIST);
88         assert(!name);
89         ret = qlist_entry_obj(tos->entry);
90         assert(ret);
91         if (consume) {
92             tos->entry = qlist_next(tos->entry);
93         }
94     }
95 
96     return ret;
97 }
98 
99 static void qdict_add_key(const char *key, QObject *obj, void *opaque)
100 {
101     GHashTable *h = opaque;
102     g_hash_table_insert(h, (gpointer) key, NULL);
103 }
104 
105 static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv,
106                                             QObject *obj, void *qapi,
107                                             Error **errp)
108 {
109     GHashTable *h;
110     StackObject *tos = g_new0(StackObject, 1);
111 
112     assert(obj);
113     tos->obj = obj;
114     tos->qapi = qapi;
115 
116     if (qiv->strict && qobject_type(obj) == QTYPE_QDICT) {
117         h = g_hash_table_new(g_str_hash, g_str_equal);
118         qdict_iter(qobject_to_qdict(obj), qdict_add_key, h);
119         tos->h = h;
120     } else if (qobject_type(obj) == QTYPE_QLIST) {
121         tos->entry = qlist_first(qobject_to_qlist(obj));
122     }
123 
124     QSLIST_INSERT_HEAD(&qiv->stack, tos, node);
125     return tos->entry;
126 }
127 
128 
129 static void qobject_input_check_struct(Visitor *v, Error **errp)
130 {
131     QObjectInputVisitor *qiv = to_qiv(v);
132     StackObject *tos = QSLIST_FIRST(&qiv->stack);
133 
134     assert(tos && !tos->entry);
135     if (qiv->strict) {
136         GHashTable *const top_ht = tos->h;
137         if (top_ht) {
138             GHashTableIter iter;
139             const char *key;
140 
141             g_hash_table_iter_init(&iter, top_ht);
142             if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
143                 error_setg(errp, QERR_QMP_EXTRA_MEMBER, key);
144             }
145         }
146     }
147 }
148 
149 static void qobject_input_stack_object_free(StackObject *tos)
150 {
151     if (tos->h) {
152         g_hash_table_unref(tos->h);
153     }
154 
155     g_free(tos);
156 }
157 
158 static void qobject_input_pop(Visitor *v, void **obj)
159 {
160     QObjectInputVisitor *qiv = to_qiv(v);
161     StackObject *tos = QSLIST_FIRST(&qiv->stack);
162 
163     assert(tos && tos->qapi == obj);
164     QSLIST_REMOVE_HEAD(&qiv->stack, node);
165     qobject_input_stack_object_free(tos);
166 }
167 
168 static void qobject_input_start_struct(Visitor *v, const char *name, void **obj,
169                                        size_t size, Error **errp)
170 {
171     QObjectInputVisitor *qiv = to_qiv(v);
172     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
173     Error *err = NULL;
174 
175     if (obj) {
176         *obj = NULL;
177     }
178     if (!qobj) {
179         return;
180     }
181     if (qobject_type(qobj) != QTYPE_QDICT) {
182         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
183                    "QDict");
184         return;
185     }
186 
187     qobject_input_push(qiv, qobj, obj, &err);
188     if (err) {
189         error_propagate(errp, err);
190         return;
191     }
192 
193     if (obj) {
194         *obj = g_malloc0(size);
195     }
196 }
197 
198 
199 static void qobject_input_start_list(Visitor *v, const char *name,
200                                      GenericList **list, size_t size,
201                                      Error **errp)
202 {
203     QObjectInputVisitor *qiv = to_qiv(v);
204     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
205     const QListEntry *entry;
206 
207     if (!qobj) {
208         return;
209     }
210     if (qobject_type(qobj) != QTYPE_QLIST) {
211         if (list) {
212             *list = NULL;
213         }
214         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
215                    "list");
216         return;
217     }
218 
219     entry = qobject_input_push(qiv, qobj, list, errp);
220     if (list) {
221         if (entry) {
222             *list = g_malloc0(size);
223         } else {
224             *list = NULL;
225         }
226     }
227 }
228 
229 static GenericList *qobject_input_next_list(Visitor *v, GenericList *tail,
230                                             size_t size)
231 {
232     QObjectInputVisitor *qiv = to_qiv(v);
233     StackObject *so = QSLIST_FIRST(&qiv->stack);
234 
235     if (!so->entry) {
236         return NULL;
237     }
238     tail->next = g_malloc0(size);
239     return tail->next;
240 }
241 
242 
243 static void qobject_input_start_alternate(Visitor *v, const char *name,
244                                           GenericAlternate **obj, size_t size,
245                                           bool promote_int, Error **errp)
246 {
247     QObjectInputVisitor *qiv = to_qiv(v);
248     QObject *qobj = qobject_input_get_object(qiv, name, false, errp);
249 
250     if (!qobj) {
251         *obj = NULL;
252         return;
253     }
254     *obj = g_malloc0(size);
255     (*obj)->type = qobject_type(qobj);
256     if (promote_int && (*obj)->type == QTYPE_QINT) {
257         (*obj)->type = QTYPE_QFLOAT;
258     }
259 }
260 
261 static void qobject_input_type_int64(Visitor *v, const char *name, int64_t *obj,
262                                      Error **errp)
263 {
264     QObjectInputVisitor *qiv = to_qiv(v);
265     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
266     QInt *qint;
267 
268     if (!qobj) {
269         return;
270     }
271     qint = qobject_to_qint(qobj);
272     if (!qint) {
273         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
274                    "integer");
275         return;
276     }
277 
278     *obj = qint_get_int(qint);
279 }
280 
281 static void qobject_input_type_uint64(Visitor *v, const char *name,
282                                       uint64_t *obj, Error **errp)
283 {
284     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
285     QObjectInputVisitor *qiv = to_qiv(v);
286     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
287     QInt *qint;
288 
289     if (!qobj) {
290         return;
291     }
292     qint = qobject_to_qint(qobj);
293     if (!qint) {
294         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
295                    "integer");
296         return;
297     }
298 
299     *obj = qint_get_int(qint);
300 }
301 
302 static void qobject_input_type_bool(Visitor *v, const char *name, bool *obj,
303                                     Error **errp)
304 {
305     QObjectInputVisitor *qiv = to_qiv(v);
306     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
307     QBool *qbool;
308 
309     if (!qobj) {
310         return;
311     }
312     qbool = qobject_to_qbool(qobj);
313     if (!qbool) {
314         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
315                    "boolean");
316         return;
317     }
318 
319     *obj = qbool_get_bool(qbool);
320 }
321 
322 static void qobject_input_type_str(Visitor *v, const char *name, char **obj,
323                                    Error **errp)
324 {
325     QObjectInputVisitor *qiv = to_qiv(v);
326     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
327     QString *qstr;
328 
329     *obj = NULL;
330     if (!qobj) {
331         return;
332     }
333     qstr = qobject_to_qstring(qobj);
334     if (!qstr) {
335         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
336                    "string");
337         return;
338     }
339 
340     *obj = g_strdup(qstring_get_str(qstr));
341 }
342 
343 static void qobject_input_type_number(Visitor *v, const char *name, double *obj,
344                                       Error **errp)
345 {
346     QObjectInputVisitor *qiv = to_qiv(v);
347     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
348     QInt *qint;
349     QFloat *qfloat;
350 
351     if (!qobj) {
352         return;
353     }
354     qint = qobject_to_qint(qobj);
355     if (qint) {
356         *obj = qint_get_int(qobject_to_qint(qobj));
357         return;
358     }
359 
360     qfloat = qobject_to_qfloat(qobj);
361     if (qfloat) {
362         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
363         return;
364     }
365 
366     error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
367                "number");
368 }
369 
370 static void qobject_input_type_any(Visitor *v, const char *name, QObject **obj,
371                                    Error **errp)
372 {
373     QObjectInputVisitor *qiv = to_qiv(v);
374     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
375 
376     *obj = NULL;
377     if (!qobj) {
378         return;
379     }
380 
381     qobject_incref(qobj);
382     *obj = qobj;
383 }
384 
385 static void qobject_input_type_null(Visitor *v, const char *name, Error **errp)
386 {
387     QObjectInputVisitor *qiv = to_qiv(v);
388     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
389 
390     if (!qobj) {
391         return;
392     }
393 
394     if (qobject_type(qobj) != QTYPE_QNULL) {
395         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
396                    "null");
397     }
398 }
399 
400 static void qobject_input_optional(Visitor *v, const char *name, bool *present)
401 {
402     QObjectInputVisitor *qiv = to_qiv(v);
403     QObject *qobj = qobject_input_get_object(qiv, name, false, NULL);
404 
405     if (!qobj) {
406         *present = false;
407         return;
408     }
409 
410     *present = true;
411 }
412 
413 static void qobject_input_free(Visitor *v)
414 {
415     QObjectInputVisitor *qiv = to_qiv(v);
416     while (!QSLIST_EMPTY(&qiv->stack)) {
417         StackObject *tos = QSLIST_FIRST(&qiv->stack);
418 
419         QSLIST_REMOVE_HEAD(&qiv->stack, node);
420         qobject_input_stack_object_free(tos);
421     }
422 
423     qobject_decref(qiv->root);
424     g_free(qiv);
425 }
426 
427 Visitor *qobject_input_visitor_new(QObject *obj, bool strict)
428 {
429     QObjectInputVisitor *v;
430 
431     assert(obj);
432     v = g_malloc0(sizeof(*v));
433 
434     v->visitor.type = VISITOR_INPUT;
435     v->visitor.start_struct = qobject_input_start_struct;
436     v->visitor.check_struct = qobject_input_check_struct;
437     v->visitor.end_struct = qobject_input_pop;
438     v->visitor.start_list = qobject_input_start_list;
439     v->visitor.next_list = qobject_input_next_list;
440     v->visitor.end_list = qobject_input_pop;
441     v->visitor.start_alternate = qobject_input_start_alternate;
442     v->visitor.type_int64 = qobject_input_type_int64;
443     v->visitor.type_uint64 = qobject_input_type_uint64;
444     v->visitor.type_bool = qobject_input_type_bool;
445     v->visitor.type_str = qobject_input_type_str;
446     v->visitor.type_number = qobject_input_type_number;
447     v->visitor.type_any = qobject_input_type_any;
448     v->visitor.type_null = qobject_input_type_null;
449     v->visitor.optional = qobject_input_optional;
450     v->visitor.free = qobject_input_free;
451     v->strict = strict;
452 
453     v->root = obj;
454     qobject_incref(obj);
455 
456     return &v->visitor;
457 }
458