qapi/qmp-input-visitor.c

   1 /*
   2  * Input Visitor
   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 "qapi/qmp-input-visitor.h"
  15 #include "qapi/visitor-impl.h"
  16 #include "qemu/queue.h"
  17 #include "qemu-common.h"
  18 #include "qapi/qmp/types.h"
  19 #include "qapi/qmp/qerror.h"
  20
  21 #define QIV_STACK_SIZE 1024
  22
  23 typedef struct StackObject
  24 {
  25     QObject *obj;
  26     const QListEntry *entry;
  27     GHashTable *h;
  28 } StackObject;
  29
  30 struct QmpInputVisitor
  31 {
  32     Visitor visitor;
  33     StackObject stack[QIV_STACK_SIZE];
  34     int nb_stack;
  35     bool strict;
  36 };
  37
  38 static QmpInputVisitor *to_qiv(Visitor *v)
  39 {
  40     return container_of(v, QmpInputVisitor, visitor);
  41 }
  42
  43 static QObject *qmp_input_get_object(QmpInputVisitor *qiv,
  44                                      const char *name,
  45                                      bool consume)
  46 {
  47     QObject *qobj = qiv->stack[qiv->nb_stack - 1].obj;
  48
  49     if (qobj) {
  50         if (name && qobject_type(qobj) == QTYPE_QDICT) {
  51             if (qiv->stack[qiv->nb_stack - 1].h && consume) {
  52                 g_hash_table_remove(qiv->stack[qiv->nb_stack - 1].h, name);
  53             }
  54             return qdict_get(qobject_to_qdict(qobj), name);
  55         } else if (qiv->stack[qiv->nb_stack - 1].entry) {
  56             return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry);
  57         }
  58     }
  59
  60     return qobj;
  61 }
  62
  63 static void qdict_add_key(const char *key, QObject *obj, void *opaque)
  64 {
  65     GHashTable *h = opaque;
  66     g_hash_table_insert(h, (gpointer) key, NULL);
  67 }
  68
  69 static void qmp_input_push(QmpInputVisitor *qiv, QObject *obj, Error **errp)
  70 {
  71     GHashTable *h;
  72
  73     if (qiv->nb_stack >= QIV_STACK_SIZE) {
  74         error_setg(errp, "An internal buffer overran");
  75         return;
  76     }
  77
  78     qiv->stack[qiv->nb_stack].obj = obj;
  79     qiv->stack[qiv->nb_stack].entry = NULL;
  80     qiv->stack[qiv->nb_stack].h = NULL;
  81
  82     if (qiv->strict && qobject_type(obj) == QTYPE_QDICT) {
  83         h = g_hash_table_new(g_str_hash, g_str_equal);
  84         qdict_iter(qobject_to_qdict(obj), qdict_add_key, h);
  85         qiv->stack[qiv->nb_stack].h = h;
  86     }
  87
  88     qiv->nb_stack++;
  89 }
  90
  91 /** Only for qmp_input_pop. */
  92 static gboolean always_true(gpointer key, gpointer val, gpointer user_pkey)
  93 {
  94     *(const char **)user_pkey = (const char *)key;
  95     return TRUE;
  96 }
  97
  98 static void qmp_input_pop(QmpInputVisitor *qiv, Error **errp)
  99 {
 100     assert(qiv->nb_stack > 0);
 101
 102     if (qiv->strict) {
 103         GHashTable * const top_ht = qiv->stack[qiv->nb_stack - 1].h;
 104         if (top_ht) {
 105             if (g_hash_table_size(top_ht)) {
 106                 const char *key;
 107                 g_hash_table_find(top_ht, always_true, &key);
 108                 error_set(errp, QERR_QMP_EXTRA_MEMBER, key);
 109             }
 110             g_hash_table_unref(top_ht);
 111         }
 112     }
 113
 114     qiv->nb_stack--;
 115 }
 116
 117 static void qmp_input_start_struct(Visitor *v, void **obj, const char *kind,
 118                                    const char *name, size_t size, Error **errp)
 119 {
 120     QmpInputVisitor *qiv = to_qiv(v);
 121     QObject *qobj = qmp_input_get_object(qiv, name, true);
 122     Error *err = NULL;
 123
 124     if (!qobj || qobject_type(qobj) != QTYPE_QDICT) {
 125         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 126                   "QDict");
 127         return;
 128     }
 129
 130     qmp_input_push(qiv, qobj, &err);
 131     if (err) {
 132         error_propagate(errp, err);
 133         return;
 134     }
 135
 136     if (obj) {
 137         *obj = g_malloc0(size);
 138     }
 139 }
 140
 141 static void qmp_input_end_struct(Visitor *v, Error **errp)
 142 {
 143     QmpInputVisitor *qiv = to_qiv(v);
 144
 145     qmp_input_pop(qiv, errp);
 146 }
 147
 148 static void qmp_input_start_implicit_struct(Visitor *v, void **obj,
 149                                             size_t size, Error **errp)
 150 {
 151     if (obj) {
 152         *obj = g_malloc0(size);
 153     }
 154 }
 155
 156 static void qmp_input_end_implicit_struct(Visitor *v, Error **errp)
 157 {
 158 }
 159
 160 static void qmp_input_start_list(Visitor *v, const char *name, Error **errp)
 161 {
 162     QmpInputVisitor *qiv = to_qiv(v);
 163     QObject *qobj = qmp_input_get_object(qiv, name, true);
 164
 165     if (!qobj || qobject_type(qobj) != QTYPE_QLIST) {
 166         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 167                   "list");
 168         return;
 169     }
 170
 171     qmp_input_push(qiv, qobj, errp);
 172 }
 173
 174 static GenericList *qmp_input_next_list(Visitor *v, GenericList **list,
 175                                         Error **errp)
 176 {
 177     QmpInputVisitor *qiv = to_qiv(v);
 178     GenericList *entry;
 179     StackObject *so = &qiv->stack[qiv->nb_stack - 1];
 180     bool first;
 181
 182     if (so->entry == NULL) {
 183         so->entry = qlist_first(qobject_to_qlist(so->obj));
 184         first = true;
 185     } else {
 186         so->entry = qlist_next(so->entry);
 187         first = false;
 188     }
 189
 190     if (so->entry == NULL) {
 191         return NULL;
 192     }
 193
 194     entry = g_malloc0(sizeof(*entry));
 195     if (first) {
 196         *list = entry;
 197     } else {
 198         (*list)->next = entry;
 199     }
 200
 201     return entry;
 202 }
 203
 204 static void qmp_input_end_list(Visitor *v, Error **errp)
 205 {
 206     QmpInputVisitor *qiv = to_qiv(v);
 207
 208     qmp_input_pop(qiv, errp);
 209 }
 210
 211 static void qmp_input_get_next_type(Visitor *v, int *kind, const int *qobjects,
 212                                     const char *name, Error **errp)
 213 {
 214     QmpInputVisitor *qiv = to_qiv(v);
 215     QObject *qobj = qmp_input_get_object(qiv, name, false);
 216
 217     if (!qobj) {
 218         error_set(errp, QERR_MISSING_PARAMETER, name ? name : "null");
 219         return;
 220     }
 221     *kind = qobjects[qobject_type(qobj)];
 222 }
 223
 224 static void qmp_input_type_int(Visitor *v, int64_t *obj, const char *name,
 225                                Error **errp)
 226 {
 227     QmpInputVisitor *qiv = to_qiv(v);
 228     QObject *qobj = qmp_input_get_object(qiv, name, true);
 229
 230     if (!qobj || qobject_type(qobj) != QTYPE_QINT) {
 231         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 232                   "integer");
 233         return;
 234     }
 235
 236     *obj = qint_get_int(qobject_to_qint(qobj));
 237 }
 238
 239 static void qmp_input_type_bool(Visitor *v, bool *obj, const char *name,
 240                                 Error **errp)
 241 {
 242     QmpInputVisitor *qiv = to_qiv(v);
 243     QObject *qobj = qmp_input_get_object(qiv, name, true);
 244
 245     if (!qobj || qobject_type(qobj) != QTYPE_QBOOL) {
 246         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 247                   "boolean");
 248         return;
 249     }
 250
 251     *obj = qbool_get_int(qobject_to_qbool(qobj));
 252 }
 253
 254 static void qmp_input_type_str(Visitor *v, char **obj, const char *name,
 255                                Error **errp)
 256 {
 257     QmpInputVisitor *qiv = to_qiv(v);
 258     QObject *qobj = qmp_input_get_object(qiv, name, true);
 259
 260     if (!qobj || qobject_type(qobj) != QTYPE_QSTRING) {
 261         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 262                   "string");
 263         return;
 264     }
 265
 266     *obj = g_strdup(qstring_get_str(qobject_to_qstring(qobj)));
 267 }
 268
 269 static void qmp_input_type_number(Visitor *v, double *obj, const char *name,
 270                                   Error **errp)
 271 {
 272     QmpInputVisitor *qiv = to_qiv(v);
 273     QObject *qobj = qmp_input_get_object(qiv, name, true);
 274
 275     if (!qobj || (qobject_type(qobj) != QTYPE_QFLOAT &&
 276         qobject_type(qobj) != QTYPE_QINT)) {
 277         error_set(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 278                   "number");
 279         return;
 280     }
 281
 282     if (qobject_type(qobj) == QTYPE_QINT) {
 283         *obj = qint_get_int(qobject_to_qint(qobj));
 284     } else {
 285         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
 286     }
 287 }
 288
 289 static void qmp_input_optional(Visitor *v, bool *present, const char *name,
 290                                Error **errp)
 291 {
 292     QmpInputVisitor *qiv = to_qiv(v);
 293     QObject *qobj = qmp_input_get_object(qiv, name, true);
 294
 295     if (!qobj) {
 296         *present = false;
 297         return;
 298     }
 299
 300     *present = true;
 301 }
 302
 303 Visitor *qmp_input_get_visitor(QmpInputVisitor *v)
 304 {
 305     return &v->visitor;
 306 }
 307
 308 void qmp_input_visitor_cleanup(QmpInputVisitor *v)
 309 {
 310     qobject_decref(v->stack[0].obj);
 311     g_free(v);
 312 }
 313
 314 QmpInputVisitor *qmp_input_visitor_new(QObject *obj)
 315 {
 316     QmpInputVisitor *v;
 317
 318     v = g_malloc0(sizeof(*v));
 319
 320     v->visitor.start_struct = qmp_input_start_struct;
 321     v->visitor.end_struct = qmp_input_end_struct;
 322     v->visitor.start_implicit_struct = qmp_input_start_implicit_struct;
 323     v->visitor.end_implicit_struct = qmp_input_end_implicit_struct;
 324     v->visitor.start_list = qmp_input_start_list;
 325     v->visitor.next_list = qmp_input_next_list;
 326     v->visitor.end_list = qmp_input_end_list;
 327     v->visitor.type_enum = input_type_enum;
 328     v->visitor.type_int = qmp_input_type_int;
 329     v->visitor.type_bool = qmp_input_type_bool;
 330     v->visitor.type_str = qmp_input_type_str;
 331     v->visitor.type_number = qmp_input_type_number;
 332     v->visitor.optional = qmp_input_optional;
 333     v->visitor.get_next_type = qmp_input_get_next_type;
 334
 335     qmp_input_push(v, obj, NULL);
 336     qobject_incref(obj);
 337
 338     return v;
 339 }
 340
 341 QmpInputVisitor *qmp_input_visitor_new_strict(QObject *obj)
 342 {
 343     QmpInputVisitor *v;
 344
 345     v = qmp_input_visitor_new(obj);
 346     v->strict = true;
 347
 348     return v;
 349 }