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   <[email protected]>
   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 (!qobj) {
 200         return;
 201     }
 202     if (qobject_type(qobj) != QTYPE_QLIST) {
 203         if (list) {
 204             *list = NULL;
 205         }
 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 (list) {
 213         if (entry) {
 214             *list = g_malloc0(size);
 215         } else {
 216             *list = NULL;
 217         }
 218     }
 219 }
 220
 221 static GenericList *qobject_input_next_list(Visitor *v, GenericList *tail,
 222                                             size_t size)
 223 {
 224     QObjectInputVisitor *qiv = to_qiv(v);
 225     StackObject *so = QSLIST_FIRST(&qiv->stack);
 226
 227     if (!so->entry) {
 228         return NULL;
 229     }
 230     tail->next = g_malloc0(size);
 231     return tail->next;
 232 }
 233
 234
 235 static void qobject_input_start_alternate(Visitor *v, const char *name,
 236                                           GenericAlternate **obj, size_t size,
 237                                           bool promote_int, Error **errp)
 238 {
 239     QObjectInputVisitor *qiv = to_qiv(v);
 240     QObject *qobj = qobject_input_get_object(qiv, name, false, errp);
 241
 242     if (!qobj) {
 243         *obj = NULL;
 244         return;
 245     }
 246     *obj = g_malloc0(size);
 247     (*obj)->type = qobject_type(qobj);
 248     if (promote_int && (*obj)->type == QTYPE_QINT) {
 249         (*obj)->type = QTYPE_QFLOAT;
 250     }
 251 }
 252
 253 static void qobject_input_type_int64(Visitor *v, const char *name, int64_t *obj,
 254                                      Error **errp)
 255 {
 256     QObjectInputVisitor *qiv = to_qiv(v);
 257     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 258     QInt *qint;
 259
 260     if (!qobj) {
 261         return;
 262     }
 263     qint = qobject_to_qint(qobj);
 264     if (!qint) {
 265         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 266                    "integer");
 267         return;
 268     }
 269
 270     *obj = qint_get_int(qint);
 271 }
 272
 273 static void qobject_input_type_uint64(Visitor *v, const char *name,
 274                                       uint64_t *obj, Error **errp)
 275 {
 276     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
 277     QObjectInputVisitor *qiv = to_qiv(v);
 278     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 279     QInt *qint;
 280
 281     if (!qobj) {
 282         return;
 283     }
 284     qint = qobject_to_qint(qobj);
 285     if (!qint) {
 286         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 287                    "integer");
 288         return;
 289     }
 290
 291     *obj = qint_get_int(qint);
 292 }
 293
 294 static void qobject_input_type_bool(Visitor *v, const char *name, bool *obj,
 295                                     Error **errp)
 296 {
 297     QObjectInputVisitor *qiv = to_qiv(v);
 298     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 299     QBool *qbool;
 300
 301     if (!qobj) {
 302         return;
 303     }
 304     qbool = qobject_to_qbool(qobj);
 305     if (!qbool) {
 306         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 307                    "boolean");
 308         return;
 309     }
 310
 311     *obj = qbool_get_bool(qbool);
 312 }
 313
 314 static void qobject_input_type_str(Visitor *v, const char *name, char **obj,
 315                                    Error **errp)
 316 {
 317     QObjectInputVisitor *qiv = to_qiv(v);
 318     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 319     QString *qstr;
 320
 321     *obj = NULL;
 322     if (!qobj) {
 323         return;
 324     }
 325     qstr = qobject_to_qstring(qobj);
 326     if (!qstr) {
 327         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 328                    "string");
 329         return;
 330     }
 331
 332     *obj = g_strdup(qstring_get_str(qstr));
 333 }
 334
 335 static void qobject_input_type_number(Visitor *v, const char *name, double *obj,
 336                                       Error **errp)
 337 {
 338     QObjectInputVisitor *qiv = to_qiv(v);
 339     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 340     QInt *qint;
 341     QFloat *qfloat;
 342
 343     if (!qobj) {
 344         return;
 345     }
 346     qint = qobject_to_qint(qobj);
 347     if (qint) {
 348         *obj = qint_get_int(qobject_to_qint(qobj));
 349         return;
 350     }
 351
 352     qfloat = qobject_to_qfloat(qobj);
 353     if (qfloat) {
 354         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
 355         return;
 356     }
 357
 358     error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 359                "number");
 360 }
 361
 362 static void qobject_input_type_any(Visitor *v, const char *name, QObject **obj,
 363                                    Error **errp)
 364 {
 365     QObjectInputVisitor *qiv = to_qiv(v);
 366     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 367
 368     *obj = NULL;
 369     if (!qobj) {
 370         return;
 371     }
 372
 373     qobject_incref(qobj);
 374     *obj = qobj;
 375 }
 376
 377 static void qobject_input_type_null(Visitor *v, const char *name, Error **errp)
 378 {
 379     QObjectInputVisitor *qiv = to_qiv(v);
 380     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 381
 382     if (!qobj) {
 383         return;
 384     }
 385
 386     if (qobject_type(qobj) != QTYPE_QNULL) {
 387         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 388                    "null");
 389     }
 390 }
 391
 392 static void qobject_input_optional(Visitor *v, const char *name, bool *present)
 393 {
 394     QObjectInputVisitor *qiv = to_qiv(v);
 395     QObject *qobj = qobject_input_get_object(qiv, name, false, NULL);
 396
 397     if (!qobj) {
 398         *present = false;
 399         return;
 400     }
 401
 402     *present = true;
 403 }
 404
 405 static void qobject_input_free(Visitor *v)
 406 {
 407     QObjectInputVisitor *qiv = to_qiv(v);
 408     while (!QSLIST_EMPTY(&qiv->stack)) {
 409         StackObject *tos = QSLIST_FIRST(&qiv->stack);
 410
 411         QSLIST_REMOVE_HEAD(&qiv->stack, node);
 412         qobject_input_stack_object_free(tos);
 413     }
 414
 415     qobject_decref(qiv->root);
 416     g_free(qiv);
 417 }
 418
 419 Visitor *qobject_input_visitor_new(QObject *obj, bool strict)
 420 {
 421     QObjectInputVisitor *v;
 422
 423     assert(obj);
 424     v = g_malloc0(sizeof(*v));
 425
 426     v->visitor.type = VISITOR_INPUT;
 427     v->visitor.start_struct = qobject_input_start_struct;
 428     v->visitor.check_struct = qobject_input_check_struct;
 429     v->visitor.end_struct = qobject_input_pop;
 430     v->visitor.start_list = qobject_input_start_list;
 431     v->visitor.next_list = qobject_input_next_list;
 432     v->visitor.end_list = qobject_input_pop;
 433     v->visitor.start_alternate = qobject_input_start_alternate;
 434     v->visitor.type_int64 = qobject_input_type_int64;
 435     v->visitor.type_uint64 = qobject_input_type_uint64;
 436     v->visitor.type_bool = qobject_input_type_bool;
 437     v->visitor.type_str = qobject_input_type_str;
 438     v->visitor.type_number = qobject_input_type_number;
 439     v->visitor.type_any = qobject_input_type_any;
 440     v->visitor.type_null = qobject_input_type_null;
 441     v->visitor.optional = qobject_input_optional;
 442     v->visitor.free = qobject_input_free;
 443     v->strict = strict;
 444
 445     v->root = obj;
 446     qobject_incref(obj);
 447
 448     return &v->visitor;
 449 }