qapi/qobject-input-visitor.c

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