qapi/qmp-output-visitor.c

   1 /*
   2  * Core Definitions for QAPI/QMP Command Registry
   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 LGPL, version 2.1 or later.
  10  * See the COPYING.LIB file in the top-level directory.
  11  *
  12  */
  13
  14 #include "qmp-output-visitor.h"
  15 #include "qemu-queue.h"
  16 #include "qemu-common.h"
  17 #include "qemu-objects.h"
  18 #include "qerror.h"
  19
  20 typedef struct QStackEntry
  21 {
  22     QObject *value;
  23     QTAILQ_ENTRY(QStackEntry) node;
  24 } QStackEntry;
  25
  26 typedef QTAILQ_HEAD(QStack, QStackEntry) QStack;
  27
  28 struct QmpOutputVisitor
  29 {
  30     Visitor visitor;
  31     QStack stack;
  32 };
  33
  34 #define qmp_output_add(qov, name, value) \
  35     qmp_output_add_obj(qov, name, QOBJECT(value))
  36 #define qmp_output_push(qov, value) qmp_output_push_obj(qov, QOBJECT(value))
  37
  38 static QmpOutputVisitor *to_qov(Visitor *v)
  39 {
  40     return container_of(v, QmpOutputVisitor, visitor);
  41 }
  42
  43 static void qmp_output_push_obj(QmpOutputVisitor *qov, QObject *value)
  44 {
  45     QStackEntry *e = qemu_mallocz(sizeof(*e));
  46
  47     e->value = value;
  48     QTAILQ_INSERT_HEAD(&qov->stack, e, node);
  49 }
  50
  51 static QObject *qmp_output_pop(QmpOutputVisitor *qov)
  52 {
  53     QStackEntry *e = QTAILQ_FIRST(&qov->stack);
  54     QObject *value;
  55     QTAILQ_REMOVE(&qov->stack, e, node);
  56     value = e->value;
  57     qemu_free(e);
  58     return value;
  59 }
  60
  61 static QObject *qmp_output_first(QmpOutputVisitor *qov)
  62 {
  63     QStackEntry *e = QTAILQ_LAST(&qov->stack, QStack);
  64     return e->value;
  65 }
  66
  67 static QObject *qmp_output_last(QmpOutputVisitor *qov)
  68 {
  69     QStackEntry *e = QTAILQ_FIRST(&qov->stack);
  70     return e->value;
  71 }
  72
  73 static void qmp_output_add_obj(QmpOutputVisitor *qov, const char *name,
  74                                QObject *value)
  75 {
  76     QObject *cur;
  77
  78     if (QTAILQ_EMPTY(&qov->stack)) {
  79         qmp_output_push_obj(qov, value);
  80         return;
  81     }
  82
  83     cur = qmp_output_last(qov);
  84
  85     switch (qobject_type(cur)) {
  86     case QTYPE_QDICT:
  87         qdict_put_obj(qobject_to_qdict(cur), name, value);
  88         break;
  89     case QTYPE_QLIST:
  90         qlist_append_obj(qobject_to_qlist(cur), value);
  91         break;
  92     default:
  93         qobject_decref(qmp_output_pop(qov));
  94         qmp_output_push_obj(qov, value);
  95         break;
  96     }
  97 }
  98
  99 static void qmp_output_start_struct(Visitor *v, void **obj, const char *kind,
 100                                     const char *name, size_t unused,
 101                                     Error **errp)
 102 {
 103     QmpOutputVisitor *qov = to_qov(v);
 104     QDict *dict = qdict_new();
 105
 106     qmp_output_add(qov, name, dict);
 107     qmp_output_push(qov, dict);
 108 }
 109
 110 static void qmp_output_end_struct(Visitor *v, Error **errp)
 111 {
 112     QmpOutputVisitor *qov = to_qov(v);
 113     qmp_output_pop(qov);
 114 }
 115
 116 static void qmp_output_start_list(Visitor *v, const char *name, Error **errp)
 117 {
 118     QmpOutputVisitor *qov = to_qov(v);
 119     QList *list = qlist_new();
 120
 121     qmp_output_add(qov, name, list);
 122     qmp_output_push(qov, list);
 123 }
 124
 125 static GenericList *qmp_output_next_list(Visitor *v, GenericList **list,
 126                                          Error **errp)
 127 {
 128     GenericList *retval = *list;
 129     *list = retval->next;
 130     return retval;
 131 }
 132
 133 static void qmp_output_end_list(Visitor *v, Error **errp)
 134 {
 135     QmpOutputVisitor *qov = to_qov(v);
 136     qmp_output_pop(qov);
 137 }
 138
 139 static void qmp_output_type_int(Visitor *v, int64_t *obj, const char *name,
 140                                 Error **errp)
 141 {
 142     QmpOutputVisitor *qov = to_qov(v);
 143     qmp_output_add(qov, name, qint_from_int(*obj));
 144 }
 145
 146 static void qmp_output_type_bool(Visitor *v, bool *obj, const char *name,
 147                                  Error **errp)
 148 {
 149     QmpOutputVisitor *qov = to_qov(v);
 150     qmp_output_add(qov, name, qbool_from_int(*obj));
 151 }
 152
 153 static void qmp_output_type_str(Visitor *v, char **obj, const char *name,
 154                                 Error **errp)
 155 {
 156     QmpOutputVisitor *qov = to_qov(v);
 157     if (*obj) {
 158         qmp_output_add(qov, name, qstring_from_str(*obj));
 159     } else {
 160         qmp_output_add(qov, name, qstring_from_str(""));
 161     }
 162 }
 163
 164 static void qmp_output_type_number(Visitor *v, double *obj, const char *name,
 165                                    Error **errp)
 166 {
 167     QmpOutputVisitor *qov = to_qov(v);
 168     qmp_output_add(qov, name, qfloat_from_double(*obj));
 169 }
 170
 171 static void qmp_output_type_enum(Visitor *v, int *obj, const char *strings[],
 172                                  const char *kind, const char *name,
 173                                  Error **errp)
 174 {
 175     int i = 0;
 176     int value = *obj;
 177     char *enum_str;
 178
 179     assert(strings);
 180     while (strings[i++] != NULL);
 181     if (value >= i - 1) {
 182         error_set(errp, QERR_INVALID_PARAMETER, name ? name : "null");
 183         return;
 184     }
 185
 186     enum_str = (char *)strings[value];
 187     qmp_output_type_str(v, &enum_str, name, errp);
 188 }
 189
 190 QObject *qmp_output_get_qobject(QmpOutputVisitor *qov)
 191 {
 192     QObject *obj = qmp_output_first(qov);
 193     if (obj) {
 194         qobject_incref(obj);
 195     }
 196     return obj;
 197 }
 198
 199 Visitor *qmp_output_get_visitor(QmpOutputVisitor *v)
 200 {
 201     return &v->visitor;
 202 }
 203
 204 void qmp_output_visitor_cleanup(QmpOutputVisitor *v)
 205 {
 206     QStackEntry *e, *tmp;
 207
 208     QTAILQ_FOREACH_SAFE(e, &v->stack, node, tmp) {
 209         QTAILQ_REMOVE(&v->stack, e, node);
 210         if (e->value) {
 211             qobject_decref(e->value);
 212         }
 213         qemu_free(e);
 214     }
 215
 216     qemu_free(v);
 217 }
 218
 219 QmpOutputVisitor *qmp_output_visitor_new(void)
 220 {
 221     QmpOutputVisitor *v;
 222
 223     v = qemu_mallocz(sizeof(*v));
 224
 225     v->visitor.start_struct = qmp_output_start_struct;
 226     v->visitor.end_struct = qmp_output_end_struct;
 227     v->visitor.start_list = qmp_output_start_list;
 228     v->visitor.next_list = qmp_output_next_list;
 229     v->visitor.end_list = qmp_output_end_list;
 230     v->visitor.type_enum = qmp_output_type_enum;
 231     v->visitor.type_int = qmp_output_type_int;
 232     v->visitor.type_bool = qmp_output_type_bool;
 233     v->visitor.type_str = qmp_output_type_str;
 234     v->visitor.type_number = qmp_output_type_number;
 235
 236     QTAILQ_INIT(&v->stack);
 237
 238     return v;
 239 }