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     const char *name;            /* Name of @obj in its parent, if any */
  26     QObject *obj;                /* QDict or QList being visited */
  27     void *qapi; /* sanity check that caller uses same pointer */
  28
  29     GHashTable *h;              /* If @obj is QDict: unvisited keys */
  30     const QListEntry *entry;    /* If @obj is QList: unvisited tail */
  31     unsigned index;             /* If @obj is QList: list index of @entry */
  32
  33     QSLIST_ENTRY(StackObject) node; /* parent */
  34 } StackObject;
  35
  36 struct QObjectInputVisitor {
  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     GString *errname;           /* Accumulator for full_name() */
  50 };
  51
  52 static QObjectInputVisitor *to_qiv(Visitor *v)
  53 {
  54     return container_of(v, QObjectInputVisitor, visitor);
  55 }
  56
  57 static const char *full_name(QObjectInputVisitor *qiv, const char *name)
  58 {
  59     StackObject *so;
  60     char buf[32];
  61
  62     if (qiv->errname) {
  63         g_string_truncate(qiv->errname, 0);
  64     } else {
  65         qiv->errname = g_string_new("");
  66     }
  67
  68     QSLIST_FOREACH(so , &qiv->stack, node) {
  69         if (qobject_type(so->obj) == QTYPE_QDICT) {
  70             g_string_prepend(qiv->errname, name);
  71             g_string_prepend_c(qiv->errname, '.');
  72         } else {
  73             snprintf(buf, sizeof(buf), "[%u]", so->index);
  74             g_string_prepend(qiv->errname, buf);
  75         }
  76         name = so->name;
  77     }
  78
  79     if (name) {
  80         g_string_prepend(qiv->errname, name);
  81     } else if (qiv->errname->str[0] == '.') {
  82         g_string_erase(qiv->errname, 0, 1);
  83     } else {
  84         return "<anonymous>";
  85     }
  86
  87     return qiv->errname->str;
  88 }
  89
  90 static QObject *qobject_input_try_get_object(QObjectInputVisitor *qiv,
  91                                              const char *name,
  92                                              bool consume)
  93 {
  94     StackObject *tos;
  95     QObject *qobj;
  96     QObject *ret;
  97
  98     if (QSLIST_EMPTY(&qiv->stack)) {
  99         /* Starting at root, name is ignored. */
 100         assert(qiv->root);
 101         return qiv->root;
 102     }
 103
 104     /* We are in a container; find the next element. */
 105     tos = QSLIST_FIRST(&qiv->stack);
 106     qobj = tos->obj;
 107     assert(qobj);
 108
 109     if (qobject_type(qobj) == QTYPE_QDICT) {
 110         assert(name);
 111         ret = qdict_get(qobject_to_qdict(qobj), name);
 112         if (tos->h && consume && ret) {
 113             bool removed = g_hash_table_remove(tos->h, name);
 114             assert(removed);
 115         }
 116     } else {
 117         assert(qobject_type(qobj) == QTYPE_QLIST);
 118         assert(!name);
 119         ret = qlist_entry_obj(tos->entry);
 120         assert(ret);
 121         if (consume) {
 122             tos->entry = qlist_next(tos->entry);
 123             tos->index++;
 124         }
 125     }
 126
 127     return ret;
 128 }
 129
 130 static QObject *qobject_input_get_object(QObjectInputVisitor *qiv,
 131                                          const char *name,
 132                                          bool consume, Error **errp)
 133 {
 134     QObject *obj = qobject_input_try_get_object(qiv, name, consume);
 135
 136     if (!obj) {
 137         error_setg(errp, QERR_MISSING_PARAMETER, full_name(qiv, name));
 138     }
 139     return obj;
 140 }
 141
 142 static void qdict_add_key(const char *key, QObject *obj, void *opaque)
 143 {
 144     GHashTable *h = opaque;
 145     g_hash_table_insert(h, (gpointer) key, NULL);
 146 }
 147
 148 static const QListEntry *qobject_input_push(QObjectInputVisitor *qiv,
 149                                             const char *name,
 150                                             QObject *obj, void *qapi)
 151 {
 152     GHashTable *h;
 153     StackObject *tos = g_new0(StackObject, 1);
 154
 155     assert(obj);
 156     tos->name = name;
 157     tos->obj = obj;
 158     tos->qapi = qapi;
 159
 160     if (qiv->strict && qobject_type(obj) == QTYPE_QDICT) {
 161         h = g_hash_table_new(g_str_hash, g_str_equal);
 162         qdict_iter(qobject_to_qdict(obj), qdict_add_key, h);
 163         tos->h = h;
 164     } else if (qobject_type(obj) == QTYPE_QLIST) {
 165         tos->entry = qlist_first(qobject_to_qlist(obj));
 166         tos->index = -1;
 167     }
 168
 169     QSLIST_INSERT_HEAD(&qiv->stack, tos, node);
 170     return tos->entry;
 171 }
 172
 173
 174 static void qobject_input_check_struct(Visitor *v, Error **errp)
 175 {
 176     QObjectInputVisitor *qiv = to_qiv(v);
 177     StackObject *tos = QSLIST_FIRST(&qiv->stack);
 178
 179     assert(tos && !tos->entry);
 180     if (qiv->strict) {
 181         GHashTable *const top_ht = tos->h;
 182         if (top_ht) {
 183             GHashTableIter iter;
 184             const char *key;
 185
 186             g_hash_table_iter_init(&iter, top_ht);
 187             if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) {
 188                 error_setg(errp, "Parameter '%s' is unexpected",
 189                            full_name(qiv, key));
 190             }
 191         }
 192     }
 193 }
 194
 195 static void qobject_input_stack_object_free(StackObject *tos)
 196 {
 197     if (tos->h) {
 198         g_hash_table_unref(tos->h);
 199     }
 200
 201     g_free(tos);
 202 }
 203
 204 static void qobject_input_pop(Visitor *v, void **obj)
 205 {
 206     QObjectInputVisitor *qiv = to_qiv(v);
 207     StackObject *tos = QSLIST_FIRST(&qiv->stack);
 208
 209     assert(tos && tos->qapi == obj);
 210     QSLIST_REMOVE_HEAD(&qiv->stack, node);
 211     qobject_input_stack_object_free(tos);
 212 }
 213
 214 static void qobject_input_start_struct(Visitor *v, const char *name, void **obj,
 215                                        size_t size, Error **errp)
 216 {
 217     QObjectInputVisitor *qiv = to_qiv(v);
 218     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 219
 220     if (obj) {
 221         *obj = NULL;
 222     }
 223     if (!qobj) {
 224         return;
 225     }
 226     if (qobject_type(qobj) != QTYPE_QDICT) {
 227         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 228                    full_name(qiv, name), "object");
 229         return;
 230     }
 231
 232     qobject_input_push(qiv, name, qobj, obj);
 233
 234     if (obj) {
 235         *obj = g_malloc0(size);
 236     }
 237 }
 238
 239
 240 static void qobject_input_start_list(Visitor *v, const char *name,
 241                                      GenericList **list, size_t size,
 242                                      Error **errp)
 243 {
 244     QObjectInputVisitor *qiv = to_qiv(v);
 245     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 246     const QListEntry *entry;
 247
 248     if (list) {
 249         *list = NULL;
 250     }
 251     if (!qobj) {
 252         return;
 253     }
 254     if (qobject_type(qobj) != QTYPE_QLIST) {
 255         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 256                    full_name(qiv, name), "array");
 257         return;
 258     }
 259
 260     entry = qobject_input_push(qiv, name, qobj, list);
 261     if (entry && list) {
 262         *list = g_malloc0(size);
 263     }
 264 }
 265
 266 static GenericList *qobject_input_next_list(Visitor *v, GenericList *tail,
 267                                             size_t size)
 268 {
 269     QObjectInputVisitor *qiv = to_qiv(v);
 270     StackObject *so = QSLIST_FIRST(&qiv->stack);
 271
 272     if (!so->entry) {
 273         return NULL;
 274     }
 275     tail->next = g_malloc0(size);
 276     return tail->next;
 277 }
 278
 279
 280 static void qobject_input_start_alternate(Visitor *v, const char *name,
 281                                           GenericAlternate **obj, size_t size,
 282                                           bool promote_int, Error **errp)
 283 {
 284     QObjectInputVisitor *qiv = to_qiv(v);
 285     QObject *qobj = qobject_input_get_object(qiv, name, false, errp);
 286
 287     if (!qobj) {
 288         *obj = NULL;
 289         return;
 290     }
 291     *obj = g_malloc0(size);
 292     (*obj)->type = qobject_type(qobj);
 293     if (promote_int && (*obj)->type == QTYPE_QINT) {
 294         (*obj)->type = QTYPE_QFLOAT;
 295     }
 296 }
 297
 298 static void qobject_input_type_int64(Visitor *v, const char *name, int64_t *obj,
 299                                      Error **errp)
 300 {
 301     QObjectInputVisitor *qiv = to_qiv(v);
 302     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 303     QInt *qint;
 304
 305     if (!qobj) {
 306         return;
 307     }
 308     qint = qobject_to_qint(qobj);
 309     if (!qint) {
 310         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 311                    full_name(qiv, name), "integer");
 312         return;
 313     }
 314
 315     *obj = qint_get_int(qint);
 316 }
 317
 318 static void qobject_input_type_uint64(Visitor *v, const char *name,
 319                                       uint64_t *obj, Error **errp)
 320 {
 321     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
 322     QObjectInputVisitor *qiv = to_qiv(v);
 323     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 324     QInt *qint;
 325
 326     if (!qobj) {
 327         return;
 328     }
 329     qint = qobject_to_qint(qobj);
 330     if (!qint) {
 331         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 332                    full_name(qiv, name), "integer");
 333         return;
 334     }
 335
 336     *obj = qint_get_int(qint);
 337 }
 338
 339 static void qobject_input_type_bool(Visitor *v, const char *name, bool *obj,
 340                                     Error **errp)
 341 {
 342     QObjectInputVisitor *qiv = to_qiv(v);
 343     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 344     QBool *qbool;
 345
 346     if (!qobj) {
 347         return;
 348     }
 349     qbool = qobject_to_qbool(qobj);
 350     if (!qbool) {
 351         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 352                    full_name(qiv, name), "boolean");
 353         return;
 354     }
 355
 356     *obj = qbool_get_bool(qbool);
 357 }
 358
 359 static void qobject_input_type_str(Visitor *v, const char *name, char **obj,
 360                                    Error **errp)
 361 {
 362     QObjectInputVisitor *qiv = to_qiv(v);
 363     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 364     QString *qstr;
 365
 366     *obj = NULL;
 367     if (!qobj) {
 368         return;
 369     }
 370     qstr = qobject_to_qstring(qobj);
 371     if (!qstr) {
 372         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 373                    full_name(qiv, name), "string");
 374         return;
 375     }
 376
 377     *obj = g_strdup(qstring_get_str(qstr));
 378 }
 379
 380 static void qobject_input_type_number(Visitor *v, const char *name, double *obj,
 381                                       Error **errp)
 382 {
 383     QObjectInputVisitor *qiv = to_qiv(v);
 384     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 385     QInt *qint;
 386     QFloat *qfloat;
 387
 388     if (!qobj) {
 389         return;
 390     }
 391     qint = qobject_to_qint(qobj);
 392     if (qint) {
 393         *obj = qint_get_int(qobject_to_qint(qobj));
 394         return;
 395     }
 396
 397     qfloat = qobject_to_qfloat(qobj);
 398     if (qfloat) {
 399         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
 400         return;
 401     }
 402
 403     error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 404                full_name(qiv, name), "number");
 405 }
 406
 407 static void qobject_input_type_any(Visitor *v, const char *name, QObject **obj,
 408                                    Error **errp)
 409 {
 410     QObjectInputVisitor *qiv = to_qiv(v);
 411     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 412
 413     *obj = NULL;
 414     if (!qobj) {
 415         return;
 416     }
 417
 418     qobject_incref(qobj);
 419     *obj = qobj;
 420 }
 421
 422 static void qobject_input_type_null(Visitor *v, const char *name, Error **errp)
 423 {
 424     QObjectInputVisitor *qiv = to_qiv(v);
 425     QObject *qobj = qobject_input_get_object(qiv, name, true, errp);
 426
 427     if (!qobj) {
 428         return;
 429     }
 430
 431     if (qobject_type(qobj) != QTYPE_QNULL) {
 432         error_setg(errp, QERR_INVALID_PARAMETER_TYPE,
 433                    full_name(qiv, name), "null");
 434     }
 435 }
 436
 437 static void qobject_input_optional(Visitor *v, const char *name, bool *present)
 438 {
 439     QObjectInputVisitor *qiv = to_qiv(v);
 440     QObject *qobj = qobject_input_try_get_object(qiv, name, false);
 441
 442     if (!qobj) {
 443         *present = false;
 444         return;
 445     }
 446
 447     *present = true;
 448 }
 449
 450 static void qobject_input_free(Visitor *v)
 451 {
 452     QObjectInputVisitor *qiv = to_qiv(v);
 453
 454     while (!QSLIST_EMPTY(&qiv->stack)) {
 455         StackObject *tos = QSLIST_FIRST(&qiv->stack);
 456
 457         QSLIST_REMOVE_HEAD(&qiv->stack, node);
 458         qobject_input_stack_object_free(tos);
 459     }
 460
 461     qobject_decref(qiv->root);
 462     if (qiv->errname) {
 463         g_string_free(qiv->errname, TRUE);
 464     }
 465     g_free(qiv);
 466 }
 467
 468 Visitor *qobject_input_visitor_new(QObject *obj, bool strict)
 469 {
 470     QObjectInputVisitor *v;
 471
 472     assert(obj);
 473     v = g_malloc0(sizeof(*v));
 474
 475     v->visitor.type = VISITOR_INPUT;
 476     v->visitor.start_struct = qobject_input_start_struct;
 477     v->visitor.check_struct = qobject_input_check_struct;
 478     v->visitor.end_struct = qobject_input_pop;
 479     v->visitor.start_list = qobject_input_start_list;
 480     v->visitor.next_list = qobject_input_next_list;
 481     v->visitor.end_list = qobject_input_pop;
 482     v->visitor.start_alternate = qobject_input_start_alternate;
 483     v->visitor.type_int64 = qobject_input_type_int64;
 484     v->visitor.type_uint64 = qobject_input_type_uint64;
 485     v->visitor.type_bool = qobject_input_type_bool;
 486     v->visitor.type_str = qobject_input_type_str;
 487     v->visitor.type_number = qobject_input_type_number;
 488     v->visitor.type_any = qobject_input_type_any;
 489     v->visitor.type_null = qobject_input_type_null;
 490     v->visitor.optional = qobject_input_optional;
 491     v->visitor.free = qobject_input_free;
 492     v->strict = strict;
 493
 494     v->root = obj;
 495     qobject_incref(obj);
 496
 497     return &v->visitor;
 498 }