summaryrefslogtreecommitdiff
path: root/qapi/qmp-output-visitor.c
blob: 4d3cf78333bbcb88ea88f242568a5ecbccf1f605 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
/*
 * Core Definitions for QAPI/QMP Command Registry
 *
 * Copyright (C) 2012-2016 Red Hat, Inc.
 * Copyright IBM, Corp. 2011
 *
 * Authors:
 *  Anthony Liguori   <aliguori@us.ibm.com>
 *
 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 * See the COPYING.LIB file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include "qapi/qmp-output-visitor.h"
#include "qapi/visitor-impl.h"
#include "qemu/queue.h"
#include "qemu-common.h"
#include "qapi/qmp/types.h"

typedef struct QStackEntry
{
    QObject *value;
    QTAILQ_ENTRY(QStackEntry) node;
} QStackEntry;

typedef QTAILQ_HEAD(QStack, QStackEntry) QStack;

struct QmpOutputVisitor
{
    Visitor visitor;
    QStack stack; /* Stack of containers that haven't yet been finished */
    QObject *root; /* Root of the output visit */
};

#define qmp_output_add(qov, name, value) \
    qmp_output_add_obj(qov, name, QOBJECT(value))
#define qmp_output_push(qov, value) qmp_output_push_obj(qov, QOBJECT(value))

static QmpOutputVisitor *to_qov(Visitor *v)
{
    return container_of(v, QmpOutputVisitor, visitor);
}

/* Push @value onto the stack of current QObjects being built */
static void qmp_output_push_obj(QmpOutputVisitor *qov, QObject *value)
{
    QStackEntry *e = g_malloc0(sizeof(*e));

    assert(qov->root);
    assert(value);
    e->value = value;
    QTAILQ_INSERT_HEAD(&qov->stack, e, node);
}

/* Pop a value off the stack of QObjects being built, and return it. */
static QObject *qmp_output_pop(QmpOutputVisitor *qov)
{
    QStackEntry *e = QTAILQ_FIRST(&qov->stack);
    QObject *value;

    assert(e);
    QTAILQ_REMOVE(&qov->stack, e, node);
    value = e->value;
    assert(value);
    g_free(e);
    return value;
}

/* Add @value to the current QObject being built.
 * If the stack is visiting a dictionary or list, @value is now owned
 * by that container. Otherwise, @value is now the root.  */
static void qmp_output_add_obj(QmpOutputVisitor *qov, const char *name,
                               QObject *value)
{
    QStackEntry *e = QTAILQ_FIRST(&qov->stack);
    QObject *cur = e ? e->value : NULL;

    if (!cur) {
        /* Don't allow reuse of visitor on more than one root */
        assert(!qov->root);
        qov->root = value;
    } else {
        switch (qobject_type(cur)) {
        case QTYPE_QDICT:
            assert(name);
            qdict_put_obj(qobject_to_qdict(cur), name, value);
            break;
        case QTYPE_QLIST:
            assert(!name);
            qlist_append_obj(qobject_to_qlist(cur), value);
            break;
        default:
            g_assert_not_reached();
        }
    }
}

static void qmp_output_start_struct(Visitor *v, const char *name, void **obj,
                                    size_t unused, Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    QDict *dict = qdict_new();

    qmp_output_add(qov, name, dict);
    qmp_output_push(qov, dict);
}

static void qmp_output_end_struct(Visitor *v)
{
    QmpOutputVisitor *qov = to_qov(v);
    QObject *value = qmp_output_pop(qov);
    assert(qobject_type(value) == QTYPE_QDICT);
}

static void qmp_output_start_list(Visitor *v, const char *name,
                                  GenericList **listp, size_t size,
                                  Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    QList *list = qlist_new();

    qmp_output_add(qov, name, list);
    qmp_output_push(qov, list);
}

static GenericList *qmp_output_next_list(Visitor *v, GenericList *tail,
                                         size_t size)
{
    return tail->next;
}

static void qmp_output_end_list(Visitor *v)
{
    QmpOutputVisitor *qov = to_qov(v);
    QObject *value = qmp_output_pop(qov);
    assert(qobject_type(value) == QTYPE_QLIST);
}

static void qmp_output_type_int64(Visitor *v, const char *name, int64_t *obj,
                                  Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    qmp_output_add(qov, name, qint_from_int(*obj));
}

static void qmp_output_type_uint64(Visitor *v, const char *name, uint64_t *obj,
                                   Error **errp)
{
    /* FIXME: QMP outputs values larger than INT64_MAX as negative */
    QmpOutputVisitor *qov = to_qov(v);
    qmp_output_add(qov, name, qint_from_int(*obj));
}

static void qmp_output_type_bool(Visitor *v, const char *name, bool *obj,
                                 Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    qmp_output_add(qov, name, qbool_from_bool(*obj));
}

static void qmp_output_type_str(Visitor *v, const char *name, char **obj,
                                Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    if (*obj) {
        qmp_output_add(qov, name, qstring_from_str(*obj));
    } else {
        qmp_output_add(qov, name, qstring_from_str(""));
    }
}

static void qmp_output_type_number(Visitor *v, const char *name, double *obj,
                                   Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    qmp_output_add(qov, name, qfloat_from_double(*obj));
}

static void qmp_output_type_any(Visitor *v, const char *name, QObject **obj,
                                Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    qobject_incref(*obj);
    qmp_output_add_obj(qov, name, *obj);
}

static void qmp_output_type_null(Visitor *v, const char *name, Error **errp)
{
    QmpOutputVisitor *qov = to_qov(v);
    qmp_output_add_obj(qov, name, qnull());
}

/* Finish building, and return the root object.
 * The root object is never null. The caller becomes the object's
 * owner, and should use qobject_decref() when done with it.  */
QObject *qmp_output_get_qobject(QmpOutputVisitor *qov)
{
    /* A visit must have occurred, with each start paired with end.  */
    assert(qov->root && QTAILQ_EMPTY(&qov->stack));

    qobject_incref(qov->root);
    return qov->root;
}

Visitor *qmp_output_get_visitor(QmpOutputVisitor *v)
{
    return &v->visitor;
}

void qmp_output_visitor_cleanup(QmpOutputVisitor *v)
{
    QStackEntry *e, *tmp;

    QTAILQ_FOREACH_SAFE(e, &v->stack, node, tmp) {
        QTAILQ_REMOVE(&v->stack, e, node);
        g_free(e);
    }

    qobject_decref(v->root);
    g_free(v);
}

QmpOutputVisitor *qmp_output_visitor_new(void)
{
    QmpOutputVisitor *v;

    v = g_malloc0(sizeof(*v));

    v->visitor.type = VISITOR_OUTPUT;
    v->visitor.start_struct = qmp_output_start_struct;
    v->visitor.end_struct = qmp_output_end_struct;
    v->visitor.start_list = qmp_output_start_list;
    v->visitor.next_list = qmp_output_next_list;
    v->visitor.end_list = qmp_output_end_list;
    v->visitor.type_int64 = qmp_output_type_int64;
    v->visitor.type_uint64 = qmp_output_type_uint64;
    v->visitor.type_bool = qmp_output_type_bool;
    v->visitor.type_str = qmp_output_type_str;
    v->visitor.type_number = qmp_output_type_number;
    v->visitor.type_any = qmp_output_type_any;
    v->visitor.type_null = qmp_output_type_null;

    QTAILQ_INIT(&v->stack);

    return v;
}