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 #define QIV_STACK_SIZE 1024
  25
  26 typedef struct StackObject
  27 {
  28     QObject *obj; /* Object being visited */
  29     void *qapi; /* sanity check that caller uses same pointer */
  30
  31     GHashTable *h;           /* If obj is dict: unvisited keys */
  32     const QListEntry *entry; /* If obj is list: unvisited tail */
  33
  34     QSLIST_ENTRY(StackObject) node;
  35 } StackObject;
  36
  37 struct QObjectInputVisitor
  38 {
  39     Visitor visitor;
  40
  41     /* Root of visit at visitor creation. */
  42     QObject *root;
  43
  44     /* Stack of objects being visited (all entries will be either
  45      * QDict or QList). */
  46     QSLIST_HEAD(, StackObject) stack;
  47
  48     /* True to reject parse in visit_end_struct() if unvisited keys remain. */
  49     bool strict;
  50 };
  51
  52 static QObjectInputVisitor *to_qiv(Visitor *v)
  53 {
  54     return container_of(v, QObjectInputVisitor, visitor);
  55 }
  56
  57 static QObject *qobject_input_get_object(QObjectInputVisitor *qiv,
  58                                          const char *name,
  59                                          bool consume, Error **errp)
  60 {
  61     StackObject *tos;
  62     QObject *qobj;
  63     QObject *ret;
  64
  65     if (QSLIST_EMPTY(&qiv->stack)) {
  66         /* Starting at root, name is ignored. */
  67         assert(qiv->root);
  68         return qiv->root;
  69     }
  70
  71     /* We are in a container; find the next element. */
  72     tos = QSLIST_FIRST(&qiv->stack);
  73     qobj = tos->obj;
  74     assert(qobj);
  75
  76     if (qobject_type(qobj) == QTYPE_QDICT) {
  77         assert(name);
  78         ret = qdict_get(qobject_to_qdict(qobj), name);
  79         if (tos->h && consume && ret) {
  80             bool removed = g_hash_table_remove(tos->h, name);
  81             assert(removed);
  82         }
  83         if (!ret) {
  84             error_setg(errp, QERR_MISSING_PARAMETER, name);
  85         }
  86     } else {
  87         assert(qobject_type(qobj) == QTYPE_QLIST);
  88         assert(!name);
  89         ret = qlist_entry_obj(tos->entry);
  90         assert(ret);
  91         if (consume) {
  92             tos->entry = qlist_next(tos->entry);
  93         }
  94     }
  95
  96     return ret;
  97 }
  98
  99 static void qdict_add_key(const char *key, QObject *obj, void *opaque)
 100 {
 101     GHashTable *h = opaque;
 102     g_hash_table_insert(h, (gpointer) key, NULL);
 103 }
 104
 105 static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv,
 106                                             QObject *obj, void *qapi,
 107                                             Error **errp)
 108 {
 109     GHashTable *h;
 110     StackObject *tos = g_new0(StackObject, 1);
 111
 112     assert(obj);
 113     tos->obj = obj;
 114     tos->qapi = qapi;
 115
 116     if (qiv->strict && qobject_type(obj) == QTYPE_QDICT) {
 117         h = g_hash_table_new(g_str_hash, g_str_equal);
 118         qdict_iter(qobject_to_qdict(obj), qdict_add_key, h);
 119         tos->h = h;
 120     } else if (qobject_type(obj) == QTYPE_QLIST) {
 121         tos->entry = qlist_first(qobject_to_qlist(obj));
 122     }
 123
 124     QSLIST_INSERT_HEAD(&qiv->stack, tos, node);
 125     return tos->entry;
 126 }
 127
 128
 129 static void qobject_input_check_struct(Visitor *v, Error **errp)
 130 {
 131     QObjectInputVisitor *qiv = to_qiv(v);
 132     StackObject *tos = QSLIST_FIRST(&qiv->stack);
 133
 134     assert(tos && !tos->entry);
 135     if (qiv->strict) {
 136         GHashTable *const top_ht = tos->h;
 137         if (top_ht) {
 138             GHashTableIter iter;
 139             const char *key;
 140
 141             g_hash_table_iter_init(&iter, top_ht);
 142             if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
 143                 error_setg(errp, QERR_QMP_EXTRA_MEMBER, key);
 144             }
 145         }
 146     }
 147 }
 148
 149 static void qobject_input_stack_object_free(StackObject *tos)
 150 {
 151     if (tos->h) {
 152         g_hash_table_unref(tos->h);
 153     }
 154
 155     g_free(tos);
 156 }
 157
 158 static void qobject_input_pop(Visitor *v, void **obj)
 159 {
 160     QObjectInputVisitor *qiv = to_qiv(v);
 161     StackObject *tos = QSLIST_FIRST(&qiv->stack);
 162
 163     assert(tos && tos->qapi == obj);
 164     QSLIST_REMOVE_HEAD(&qiv->stack, node);
 165     qobject_input_stack_object_free(tos);
 166 }
 167
 168 static void qobject_input_start_struct(Visitor *v, const char *name, void **obj,
 169                                        size_t size, Error **errp)
 170 {
 171     QObjectInputVisitor *qiv = to_qiv(v);
 172     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 173     Error *err = NULL;
 174
 175     if (obj) {
 176         *obj = NULL;
 177     }
 178     if (!qobj) {
 179         return;
 180     }
 181     if (qobject_type(qobj) != QTYPE_QDICT) {
 182         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 183                    "QDict");
 184         return;
 185     }
 186
 187     qobject_input_push(qiv, qobj, obj, &err);
 188     if (err) {
 189         error_propagate(errp, err);
 190         return;
 191     }
 192
 193     if (obj) {
 194         *obj = g_malloc0(size);
 195     }
 196 }
 197
 198
 199 static void qobject_input_start_list(Visitor *v, const char *name,
 200                                      GenericList **list, size_t size,
 201                                      Error **errp)
 202 {
 203     QObjectInputVisitor *qiv = to_qiv(v);
 204     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 205     const QListEntry *entry;
 206
 207     if (!qobj) {
 208         return;
 209     }
 210     if (qobject_type(qobj) != QTYPE_QLIST) {
 211         if (list) {
 212             *list = NULL;
 213         }
 214         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 215                    "list");
 216         return;
 217     }
 218
 219     entry = qobject_input_push(qiv, qobj, list, errp);
 220     if (list) {
 221         if (entry) {
 222             *list = g_malloc0(size);
 223         } else {
 224             *list = NULL;
 225         }
 226     }
 227 }
 228
 229 static GenericList *qobject_input_next_list(Visitor *v, GenericList *tail,
 230                                             size_t size)
 231 {
 232     QObjectInputVisitor *qiv = to_qiv(v);
 233     StackObject *so = QSLIST_FIRST(&qiv->stack);
 234
 235     if (!so->entry) {
 236         return NULL;
 237     }
 238     tail->next = g_malloc0(size);
 239     return tail->next;
 240 }
 241
 242
 243 static void qobject_input_start_alternate(Visitor *v, const char *name,
 244                                           GenericAlternate **obj, size_t size,
 245                                           bool promote_int, Error **errp)
 246 {
 247     QObjectInputVisitor *qiv = to_qiv(v);
 248     QObject *qobj = qobject_input_get_object(qiv, name, false, errp);
 249
 250     if (!qobj) {
 251         *obj = NULL;
 252         return;
 253     }
 254     *obj = g_malloc0(size);
 255     (*obj)->type = qobject_type(qobj);
 256     if (promote_int && (*obj)->type == QTYPE_QINT) {
 257         (*obj)->type = QTYPE_QFLOAT;
 258     }
 259 }
 260
 261 static void qobject_input_type_int64(Visitor *v, const char *name, int64_t *obj,
 262                                      Error **errp)
 263 {
 264     QObjectInputVisitor *qiv = to_qiv(v);
 265     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 266     QInt *qint;
 267
 268     if (!qobj) {
 269         return;
 270     }
 271     qint = qobject_to_qint(qobj);
 272     if (!qint) {
 273         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 274                    "integer");
 275         return;
 276     }
 277
 278     *obj = qint_get_int(qint);
 279 }
 280
 281 static void qobject_input_type_uint64(Visitor *v, const char *name,
 282                                       uint64_t *obj, Error **errp)
 283 {
 284     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
 285     QObjectInputVisitor *qiv = to_qiv(v);
 286     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 287     QInt *qint;
 288
 289     if (!qobj) {
 290         return;
 291     }
 292     qint = qobject_to_qint(qobj);
 293     if (!qint) {
 294         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 295                    "integer");
 296         return;
 297     }
 298
 299     *obj = qint_get_int(qint);
 300 }
 301
 302 static void qobject_input_type_bool(Visitor *v, const char *name, bool *obj,
 303                                     Error **errp)
 304 {
 305     QObjectInputVisitor *qiv = to_qiv(v);
 306     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 307     QBool *qbool;
 308
 309     if (!qobj) {
 310         return;
 311     }
 312     qbool = qobject_to_qbool(qobj);
 313     if (!qbool) {
 314         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 315                    "boolean");
 316         return;
 317     }
 318
 319     *obj = qbool_get_bool(qbool);
 320 }
 321
 322 static void qobject_input_type_str(Visitor *v, const char *name, char **obj,
 323                                    Error **errp)
 324 {
 325     QObjectInputVisitor *qiv = to_qiv(v);
 326     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 327     QString *qstr;
 328
 329     *obj = NULL;
 330     if (!qobj) {
 331         return;
 332     }
 333     qstr = qobject_to_qstring(qobj);
 334     if (!qstr) {
 335         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 336                    "string");
 337         return;
 338     }
 339
 340     *obj = g_strdup(qstring_get_str(qstr));
 341 }
 342
 343 static void qobject_input_type_number(Visitor *v, const char *name, double *obj,
 344                                       Error **errp)
 345 {
 346     QObjectInputVisitor *qiv = to_qiv(v);
 347     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 348     QInt *qint;
 349     QFloat *qfloat;
 350
 351     if (!qobj) {
 352         return;
 353     }
 354     qint = qobject_to_qint(qobj);
 355     if (qint) {
 356         *obj = qint_get_int(qobject_to_qint(qobj));
 357         return;
 358     }
 359
 360     qfloat = qobject_to_qfloat(qobj);
 361     if (qfloat) {
 362         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
 363         return;
 364     }
 365
 366     error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 367                "number");
 368 }
 369
 370 static void qobject_input_type_any(Visitor *v, const char *name, QObject **obj,
 371                                    Error **errp)
 372 {
 373     QObjectInputVisitor *qiv = to_qiv(v);
 374     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 375
 376     *obj = NULL;
 377     if (!qobj) {
 378         return;
 379     }
 380
 381     qobject_incref(qobj);
 382     *obj = qobj;
 383 }
 384
 385 static void qobject_input_type_null(Visitor *v, const char *name, Error **errp)
 386 {
 387     QObjectInputVisitor *qiv = to_qiv(v);
 388     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 389
 390     if (!qobj) {
 391         return;
 392     }
 393
 394     if (qobject_type(qobj) != QTYPE_QNULL) {
 395         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 396                    "null");
 397     }
 398 }
 399
 400 static void qobject_input_optional(Visitor *v, const char *name, bool *present)
 401 {
 402     QObjectInputVisitor *qiv = to_qiv(v);
 403     QObject *qobj = qobject_input_get_object(qiv, name, false, NULL);
 404
 405     if (!qobj) {
 406         *present = false;
 407         return;
 408     }
 409
 410     *present = true;
 411 }
 412
 413 static void qobject_input_free(Visitor *v)
 414 {
 415     QObjectInputVisitor *qiv = to_qiv(v);
 416     while (!QSLIST_EMPTY(&qiv->stack)) {
 417         StackObject *tos = QSLIST_FIRST(&qiv->stack);
 418
 419         QSLIST_REMOVE_HEAD(&qiv->stack, node);
 420         qobject_input_stack_object_free(tos);
 421     }
 422
 423     qobject_decref(qiv->root);
 424     g_free(qiv);
 425 }
 426
 427 Visitor *qobject_input_visitor_new(QObject *obj, bool strict)
 428 {
 429     QObjectInputVisitor *v;
 430
 431     assert(obj);
 432     v = g_malloc0(sizeof(*v));
 433
 434     v->visitor.type = VISITOR_INPUT;
 435     v->visitor.start_struct = qobject_input_start_struct;
 436     v->visitor.check_struct = qobject_input_check_struct;
 437     v->visitor.end_struct = qobject_input_pop;
 438     v->visitor.start_list = qobject_input_start_list;
 439     v->visitor.next_list = qobject_input_next_list;
 440     v->visitor.end_list = qobject_input_pop;
 441     v->visitor.start_alternate = qobject_input_start_alternate;
 442     v->visitor.type_int64 = qobject_input_type_int64;
 443     v->visitor.type_uint64 = qobject_input_type_uint64;
 444     v->visitor.type_bool = qobject_input_type_bool;
 445     v->visitor.type_str = qobject_input_type_str;
 446     v->visitor.type_number = qobject_input_type_number;
 447     v->visitor.type_any = qobject_input_type_any;
 448     v->visitor.type_null = qobject_input_type_null;
 449     v->visitor.optional = qobject_input_optional;
 450     v->visitor.free = qobject_input_free;
 451     v->strict = strict;
 452
 453     v->root = obj;
 454     qobject_incref(obj);
 455
 456     return &v->visitor;
 457 }