Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20210921' into staging
[qemu.git] / qapi / qobject-output-visitor.c
1 /*
2 * Core Definitions for QAPI/QMP Command Registry
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/compat-policy.h"
17 #include "qapi/qobject-output-visitor.h"
18 #include "qapi/visitor-impl.h"
19 #include "qemu/queue.h"
20 #include "qapi/qmp/qbool.h"
21 #include "qapi/qmp/qdict.h"
22 #include "qapi/qmp/qlist.h"
23 #include "qapi/qmp/qnull.h"
24 #include "qapi/qmp/qnum.h"
25 #include "qapi/qmp/qstring.h"
26
27 typedef struct QStackEntry {
28 QObject *value;
29 void *qapi; /* sanity check that caller uses same pointer */
30 QSLIST_ENTRY(QStackEntry) node;
31 } QStackEntry;
32
33 struct QObjectOutputVisitor {
34 Visitor visitor;
35 CompatPolicyOutput deprecated_policy;
36
37 QSLIST_HEAD(, QStackEntry) stack; /* Stack of unfinished containers */
38 QObject *root; /* Root of the output visit */
39 QObject **result; /* User's storage location for result */
40 };
41
42 #define qobject_output_add(qov, name, value) \
43 qobject_output_add_obj(qov, name, QOBJECT(value))
44 #define qobject_output_push(qov, value, qapi) \
45 qobject_output_push_obj(qov, QOBJECT(value), qapi)
46
47 static QObjectOutputVisitor *to_qov(Visitor *v)
48 {
49 return container_of(v, QObjectOutputVisitor, visitor);
50 }
51
52 /* Push @value onto the stack of current QObjects being built */
53 static void qobject_output_push_obj(QObjectOutputVisitor *qov, QObject *value,
54 void *qapi)
55 {
56 QStackEntry *e = g_malloc0(sizeof(*e));
57
58 assert(qov->root);
59 assert(value);
60 e->value = value;
61 e->qapi = qapi;
62 QSLIST_INSERT_HEAD(&qov->stack, e, node);
63 }
64
65 /* Pop a value off the stack of QObjects being built, and return it. */
66 static QObject *qobject_output_pop(QObjectOutputVisitor *qov, void *qapi)
67 {
68 QStackEntry *e = QSLIST_FIRST(&qov->stack);
69 QObject *value;
70
71 assert(e);
72 assert(e->qapi == qapi);
73 QSLIST_REMOVE_HEAD(&qov->stack, node);
74 value = e->value;
75 assert(value);
76 g_free(e);
77 return value;
78 }
79
80 /* Add @value to the current QObject being built.
81 * If the stack is visiting a dictionary or list, @value is now owned
82 * by that container. Otherwise, @value is now the root. */
83 static void qobject_output_add_obj(QObjectOutputVisitor *qov, const char *name,
84 QObject *value)
85 {
86 QStackEntry *e = QSLIST_FIRST(&qov->stack);
87 QObject *cur = e ? e->value : NULL;
88
89 if (!cur) {
90 /* Don't allow reuse of visitor on more than one root */
91 assert(!qov->root);
92 qov->root = value;
93 } else {
94 switch (qobject_type(cur)) {
95 case QTYPE_QDICT:
96 assert(name);
97 qdict_put_obj(qobject_to(QDict, cur), name, value);
98 break;
99 case QTYPE_QLIST:
100 assert(!name);
101 qlist_append_obj(qobject_to(QList, cur), value);
102 break;
103 default:
104 g_assert_not_reached();
105 }
106 }
107 }
108
109 static bool qobject_output_start_struct(Visitor *v, const char *name,
110 void **obj, size_t unused, Error **errp)
111 {
112 QObjectOutputVisitor *qov = to_qov(v);
113 QDict *dict = qdict_new();
114
115 qobject_output_add(qov, name, dict);
116 qobject_output_push(qov, dict, obj);
117 return true;
118 }
119
120 static void qobject_output_end_struct(Visitor *v, void **obj)
121 {
122 QObjectOutputVisitor *qov = to_qov(v);
123 QObject *value = qobject_output_pop(qov, obj);
124 assert(qobject_type(value) == QTYPE_QDICT);
125 }
126
127 static bool qobject_output_start_list(Visitor *v, const char *name,
128 GenericList **listp, size_t size,
129 Error **errp)
130 {
131 QObjectOutputVisitor *qov = to_qov(v);
132 QList *list = qlist_new();
133
134 qobject_output_add(qov, name, list);
135 qobject_output_push(qov, list, listp);
136 return true;
137 }
138
139 static GenericList *qobject_output_next_list(Visitor *v, GenericList *tail,
140 size_t size)
141 {
142 return tail->next;
143 }
144
145 static void qobject_output_end_list(Visitor *v, void **obj)
146 {
147 QObjectOutputVisitor *qov = to_qov(v);
148 QObject *value = qobject_output_pop(qov, obj);
149 assert(qobject_type(value) == QTYPE_QLIST);
150 }
151
152 static bool qobject_output_type_int64(Visitor *v, const char *name,
153 int64_t *obj, Error **errp)
154 {
155 QObjectOutputVisitor *qov = to_qov(v);
156 qobject_output_add(qov, name, qnum_from_int(*obj));
157 return true;
158 }
159
160 static bool qobject_output_type_uint64(Visitor *v, const char *name,
161 uint64_t *obj, Error **errp)
162 {
163 QObjectOutputVisitor *qov = to_qov(v);
164 qobject_output_add(qov, name, qnum_from_uint(*obj));
165 return true;
166 }
167
168 static bool qobject_output_type_bool(Visitor *v, const char *name, bool *obj,
169 Error **errp)
170 {
171 QObjectOutputVisitor *qov = to_qov(v);
172 qobject_output_add(qov, name, qbool_from_bool(*obj));
173 return true;
174 }
175
176 static bool qobject_output_type_str(Visitor *v, const char *name, char **obj,
177 Error **errp)
178 {
179 QObjectOutputVisitor *qov = to_qov(v);
180 if (*obj) {
181 qobject_output_add(qov, name, qstring_from_str(*obj));
182 } else {
183 qobject_output_add(qov, name, qstring_from_str(""));
184 }
185 return true;
186 }
187
188 static bool qobject_output_type_number(Visitor *v, const char *name,
189 double *obj, Error **errp)
190 {
191 QObjectOutputVisitor *qov = to_qov(v);
192 qobject_output_add(qov, name, qnum_from_double(*obj));
193 return true;
194 }
195
196 static bool qobject_output_type_any(Visitor *v, const char *name,
197 QObject **obj, Error **errp)
198 {
199 QObjectOutputVisitor *qov = to_qov(v);
200
201 qobject_output_add_obj(qov, name, qobject_ref(*obj));
202 return true;
203 }
204
205 static bool qobject_output_type_null(Visitor *v, const char *name,
206 QNull **obj, Error **errp)
207 {
208 QObjectOutputVisitor *qov = to_qov(v);
209 qobject_output_add(qov, name, qnull());
210 return true;
211 }
212
213 static bool qobject_output_deprecated(Visitor *v, const char *name)
214 {
215 QObjectOutputVisitor *qov = to_qov(v);
216
217 return qov->deprecated_policy != COMPAT_POLICY_OUTPUT_HIDE;
218 }
219
220 /* Finish building, and return the root object.
221 * The root object is never null. The caller becomes the object's
222 * owner, and should use qobject_unref() when done with it. */
223 static void qobject_output_complete(Visitor *v, void *opaque)
224 {
225 QObjectOutputVisitor *qov = to_qov(v);
226
227 /* A visit must have occurred, with each start paired with end. */
228 assert(qov->root && QSLIST_EMPTY(&qov->stack));
229 assert(opaque == qov->result);
230
231 *qov->result = qobject_ref(qov->root);
232 qov->result = NULL;
233 }
234
235 static void qobject_output_free(Visitor *v)
236 {
237 QObjectOutputVisitor *qov = to_qov(v);
238 QStackEntry *e;
239
240 while (!QSLIST_EMPTY(&qov->stack)) {
241 e = QSLIST_FIRST(&qov->stack);
242 QSLIST_REMOVE_HEAD(&qov->stack, node);
243 g_free(e);
244 }
245
246 qobject_unref(qov->root);
247 g_free(qov);
248 }
249
250 Visitor *qobject_output_visitor_new(QObject **result)
251 {
252 QObjectOutputVisitor *v;
253
254 v = g_malloc0(sizeof(*v));
255
256 v->visitor.type = VISITOR_OUTPUT;
257 v->visitor.start_struct = qobject_output_start_struct;
258 v->visitor.end_struct = qobject_output_end_struct;
259 v->visitor.start_list = qobject_output_start_list;
260 v->visitor.next_list = qobject_output_next_list;
261 v->visitor.end_list = qobject_output_end_list;
262 v->visitor.type_int64 = qobject_output_type_int64;
263 v->visitor.type_uint64 = qobject_output_type_uint64;
264 v->visitor.type_bool = qobject_output_type_bool;
265 v->visitor.type_str = qobject_output_type_str;
266 v->visitor.type_number = qobject_output_type_number;
267 v->visitor.type_any = qobject_output_type_any;
268 v->visitor.type_null = qobject_output_type_null;
269 v->visitor.deprecated = qobject_output_deprecated;
270 v->visitor.complete = qobject_output_complete;
271 v->visitor.free = qobject_output_free;
272
273 *result = NULL;
274 v->result = result;
275
276 return &v->visitor;
277 }
278
279 void qobject_output_visitor_set_policy(Visitor *v,
280 CompatPolicyOutput deprecated)
281 {
282 QObjectOutputVisitor *qov = to_qov(v);
283
284 qov->deprecated_policy = deprecated;
285 }