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 "qemu/osdep.h"
  15 #include "qapi/qmp-input-visitor.h"
  16 #include "qapi/visitor-impl.h"
  17 #include "qemu/queue.h"
  18 #include "qemu-common.h"
  19 #include "qapi/qmp/types.h"
  20 #include "qapi/qmp/qerror.h"
  21
  22 #define QIV_STACK_SIZE 1024
  23
  24 typedef struct StackObject
  25 {
  26     QObject *obj;
  27     const QListEntry *entry;
  28     GHashTable *h;
  29 } StackObject;
  30
  31 struct QmpInputVisitor
  32 {
  33     Visitor visitor;
  34     StackObject stack[QIV_STACK_SIZE];
  35     int nb_stack;
  36     bool strict;
  37 };
  38
  39 static QmpInputVisitor *to_qiv(Visitor *v)
  40 {
  41     return container_of(v, QmpInputVisitor, visitor);
  42 }
  43
  44 static QObject *qmp_input_get_object(QmpInputVisitor *qiv,
  45                                      const char *name,
  46                                      bool consume)
  47 {
  48     QObject *qobj = qiv->stack[qiv->nb_stack - 1].obj;
  49
  50     if (qobj) {
  51         if (name && qobject_type(qobj) == QTYPE_QDICT) {
  52             if (qiv->stack[qiv->nb_stack - 1].h && consume) {
  53                 g_hash_table_remove(qiv->stack[qiv->nb_stack - 1].h, name);
  54             }
  55             return qdict_get(qobject_to_qdict(qobj), name);
  56         } else if (qiv->stack[qiv->nb_stack - 1].entry) {
  57             return qlist_entry_obj(qiv->stack[qiv->nb_stack - 1].entry);
  58         }
  59     }
  60
  61     return qobj;
  62 }
  63
  64 static void qdict_add_key(const char *key, QObject *obj, void *opaque)
  65 {
  66     GHashTable *h = opaque;
  67     g_hash_table_insert(h, (gpointer) key, NULL);
  68 }
  69
  70 static void qmp_input_push(QmpInputVisitor *qiv, QObject *obj, Error **errp)
  71 {
  72     GHashTable *h;
  73
  74     if (qiv->nb_stack >= QIV_STACK_SIZE) {
  75         error_setg(errp, "An internal buffer overran");
  76         return;
  77     }
  78
  79     qiv->stack[qiv->nb_stack].obj = obj;
  80     qiv->stack[qiv->nb_stack].entry = NULL;
  81     qiv->stack[qiv->nb_stack].h = NULL;
  82
  83     if (qiv->strict && qobject_type(obj) == QTYPE_QDICT) {
  84         h = g_hash_table_new(g_str_hash, g_str_equal);
  85         qdict_iter(qobject_to_qdict(obj), qdict_add_key, h);
  86         qiv->stack[qiv->nb_stack].h = h;
  87     }
  88
  89     qiv->nb_stack++;
  90 }
  91
  92 /** Only for qmp_input_pop. */
  93 static gboolean always_true(gpointer key, gpointer val, gpointer user_pkey)
  94 {
  95     *(const char **)user_pkey = (const char *)key;
  96     return TRUE;
  97 }
  98
  99 static void qmp_input_pop(QmpInputVisitor *qiv, Error **errp)
 100 {
 101     assert(qiv->nb_stack > 0);
 102
 103     if (qiv->strict) {
 104         GHashTable * const top_ht = qiv->stack[qiv->nb_stack - 1].h;
 105         if (top_ht) {
 106             if (g_hash_table_size(top_ht)) {
 107                 const char *key;
 108                 g_hash_table_find(top_ht, always_true, &key);
 109                 error_setg(errp, QERR_QMP_EXTRA_MEMBER, key);
 110             }
 111             g_hash_table_unref(top_ht);
 112         }
 113     }
 114
 115     qiv->nb_stack--;
 116 }
 117
 118 static void qmp_input_start_struct(Visitor *v, const char *name, void **obj,
 119                                    size_t size, Error **errp)
 120 {
 121     QmpInputVisitor *qiv = to_qiv(v);
 122     QObject *qobj = qmp_input_get_object(qiv, name, true);
 123     Error *err = NULL;
 124
 125     if (!qobj || qobject_type(qobj) != QTYPE_QDICT) {
 126         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 127                    "QDict");
 128         return;
 129     }
 130
 131     qmp_input_push(qiv, qobj, &err);
 132     if (err) {
 133         error_propagate(errp, err);
 134         return;
 135     }
 136
 137     if (obj) {
 138         *obj = g_malloc0(size);
 139     }
 140 }
 141
 142 static void qmp_input_end_struct(Visitor *v, Error **errp)
 143 {
 144     QmpInputVisitor *qiv = to_qiv(v);
 145
 146     qmp_input_pop(qiv, errp);
 147 }
 148
 149 static void qmp_input_start_implicit_struct(Visitor *v, void **obj,
 150                                             size_t size, Error **errp)
 151 {
 152     if (obj) {
 153         *obj = g_malloc0(size);
 154     }
 155 }
 156
 157 static void qmp_input_end_implicit_struct(Visitor *v, Error **errp)
 158 {
 159 }
 160
 161 static void qmp_input_start_list(Visitor *v, const char *name, Error **errp)
 162 {
 163     QmpInputVisitor *qiv = to_qiv(v);
 164     QObject *qobj = qmp_input_get_object(qiv, name, true);
 165
 166     if (!qobj || qobject_type(qobj) != QTYPE_QLIST) {
 167         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 168                    "list");
 169         return;
 170     }
 171
 172     qmp_input_push(qiv, qobj, errp);
 173 }
 174
 175 static GenericList *qmp_input_next_list(Visitor *v, GenericList **list,
 176                                         Error **errp)
 177 {
 178     QmpInputVisitor *qiv = to_qiv(v);
 179     GenericList *entry;
 180     StackObject *so = &qiv->stack[qiv->nb_stack - 1];
 181     bool first;
 182
 183     if (so->entry == NULL) {
 184         so->entry = qlist_first(qobject_to_qlist(so->obj));
 185         first = true;
 186     } else {
 187         so->entry = qlist_next(so->entry);
 188         first = false;
 189     }
 190
 191     if (so->entry == NULL) {
 192         return NULL;
 193     }
 194
 195     entry = g_malloc0(sizeof(*entry));
 196     if (first) {
 197         *list = entry;
 198     } else {
 199         (*list)->next = entry;
 200     }
 201
 202     return entry;
 203 }
 204
 205 static void qmp_input_end_list(Visitor *v, Error **errp)
 206 {
 207     QmpInputVisitor *qiv = to_qiv(v);
 208
 209     qmp_input_pop(qiv, &error_abort);
 210 }
 211
 212 static void qmp_input_get_next_type(Visitor *v, const char *name, QType *type,
 213                                     bool promote_int, Error **errp)
 214 {
 215     QmpInputVisitor *qiv = to_qiv(v);
 216     QObject *qobj = qmp_input_get_object(qiv, name, false);
 217
 218     if (!qobj) {
 219         error_setg(errp, QERR_MISSING_PARAMETER, name ? name : "null");
 220         return;
 221     }
 222     *type = qobject_type(qobj);
 223     if (promote_int && *type == QTYPE_QINT) {
 224         *type = QTYPE_QFLOAT;
 225     }
 226 }
 227
 228 static void qmp_input_type_int64(Visitor *v, const char *name, int64_t *obj,
 229                                  Error **errp)
 230 {
 231     QmpInputVisitor *qiv = to_qiv(v);
 232     QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));
 233
 234     if (!qint) {
 235         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 236                    "integer");
 237         return;
 238     }
 239
 240     *obj = qint_get_int(qint);
 241 }
 242
 243 static void qmp_input_type_uint64(Visitor *v, const char *name, uint64_t *obj,
 244                                   Error **errp)
 245 {
 246     /* FIXME: qobject_to_qint mishandles values over INT64_MAX */
 247     QmpInputVisitor *qiv = to_qiv(v);
 248     QInt *qint = qobject_to_qint(qmp_input_get_object(qiv, name, true));
 249
 250     if (!qint) {
 251         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 252                    "integer");
 253         return;
 254     }
 255
 256     *obj = qint_get_int(qint);
 257 }
 258
 259 static void qmp_input_type_bool(Visitor *v, const char *name, bool *obj,
 260                                 Error **errp)
 261 {
 262     QmpInputVisitor *qiv = to_qiv(v);
 263     QBool *qbool = qobject_to_qbool(qmp_input_get_object(qiv, name, true));
 264
 265     if (!qbool) {
 266         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 267                    "boolean");
 268         return;
 269     }
 270
 271     *obj = qbool_get_bool(qbool);
 272 }
 273
 274 static void qmp_input_type_str(Visitor *v, const char *name, char **obj,
 275                                Error **errp)
 276 {
 277     QmpInputVisitor *qiv = to_qiv(v);
 278     QString *qstr = qobject_to_qstring(qmp_input_get_object(qiv, name, true));
 279
 280     if (!qstr) {
 281         error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 282                    "string");
 283         return;
 284     }
 285
 286     *obj = g_strdup(qstring_get_str(qstr));
 287 }
 288
 289 static void qmp_input_type_number(Visitor *v, const char *name, double *obj,
 290                                   Error **errp)
 291 {
 292     QmpInputVisitor *qiv = to_qiv(v);
 293     QObject *qobj = qmp_input_get_object(qiv, name, true);
 294     QInt *qint;
 295     QFloat *qfloat;
 296
 297     qint = qobject_to_qint(qobj);
 298     if (qint) {
 299         *obj = qint_get_int(qobject_to_qint(qobj));
 300         return;
 301     }
 302
 303     qfloat = qobject_to_qfloat(qobj);
 304     if (qfloat) {
 305         *obj = qfloat_get_double(qobject_to_qfloat(qobj));
 306         return;
 307     }
 308
 309     error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 310                "number");
 311 }
 312
 313 static void qmp_input_type_any(Visitor *v, const char *name, QObject **obj,
 314                                Error **errp)
 315 {
 316     QmpInputVisitor *qiv = to_qiv(v);
 317     QObject *qobj = qmp_input_get_object(qiv, name, true);
 318
 319     qobject_incref(qobj);
 320     *obj = qobj;
 321 }
 322
 323 static void qmp_input_optional(Visitor *v, const char *name, bool *present)
 324 {
 325     QmpInputVisitor *qiv = to_qiv(v);
 326     QObject *qobj = qmp_input_get_object(qiv, name, true);
 327
 328     if (!qobj) {
 329         *present = false;
 330         return;
 331     }
 332
 333     *present = true;
 334 }
 335
 336 Visitor *qmp_input_get_visitor(QmpInputVisitor *v)
 337 {
 338     return &v->visitor;
 339 }
 340
 341 void qmp_input_visitor_cleanup(QmpInputVisitor *v)
 342 {
 343     qobject_decref(v->stack[0].obj);
 344     g_free(v);
 345 }
 346
 347 QmpInputVisitor *qmp_input_visitor_new(QObject *obj)
 348 {
 349     QmpInputVisitor *v;
 350
 351     v = g_malloc0(sizeof(*v));
 352
 353     v->visitor.start_struct = qmp_input_start_struct;
 354     v->visitor.end_struct = qmp_input_end_struct;
 355     v->visitor.start_implicit_struct = qmp_input_start_implicit_struct;
 356     v->visitor.end_implicit_struct = qmp_input_end_implicit_struct;
 357     v->visitor.start_list = qmp_input_start_list;
 358     v->visitor.next_list = qmp_input_next_list;
 359     v->visitor.end_list = qmp_input_end_list;
 360     v->visitor.type_enum = input_type_enum;
 361     v->visitor.type_int64 = qmp_input_type_int64;
 362     v->visitor.type_uint64 = qmp_input_type_uint64;
 363     v->visitor.type_bool = qmp_input_type_bool;
 364     v->visitor.type_str = qmp_input_type_str;
 365     v->visitor.type_number = qmp_input_type_number;
 366     v->visitor.type_any = qmp_input_type_any;
 367     v->visitor.optional = qmp_input_optional;
 368     v->visitor.get_next_type = qmp_input_get_next_type;
 369
 370     qmp_input_push(v, obj, NULL);
 371     qobject_incref(obj);
 372
 373     return v;
 374 }
 375
 376 QmpInputVisitor *qmp_input_visitor_new_strict(QObject *obj)
 377 {
 378     QmpInputVisitor *v;
 379
 380     v = qmp_input_visitor_new(obj);
 381     v->strict = true;
 382
 383     return v;
 384 }