qemu/qapi/qapi-visit-core.c
<<
>>
Prefs
   1/*
   2 * Core Definitions for QAPI Visitor Classes
   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/compat-policy.h"
  17#include "qapi/error.h"
  18#include "qapi/qmp/qerror.h"
  19#include "qapi/visitor.h"
  20#include "qapi/visitor-impl.h"
  21#include "trace.h"
  22
  23/* Zero-initialization must result in default policy */
  24QEMU_BUILD_BUG_ON(COMPAT_POLICY_INPUT_ACCEPT || COMPAT_POLICY_OUTPUT_ACCEPT);
  25
  26
  27void visit_complete(Visitor *v, void *opaque)
  28{
  29    assert(v->type != VISITOR_OUTPUT || v->complete);
  30    trace_visit_complete(v, opaque);
  31    if (v->complete) {
  32        v->complete(v, opaque);
  33    }
  34}
  35
  36void visit_free(Visitor *v)
  37{
  38    trace_visit_free(v);
  39    if (v) {
  40        v->free(v);
  41    }
  42}
  43
  44bool visit_start_struct(Visitor *v, const char *name, void **obj,
  45                        size_t size, Error **errp)
  46{
  47    bool ok;
  48
  49    trace_visit_start_struct(v, name, obj, size);
  50    if (obj) {
  51        assert(size);
  52        assert(!(v->type & VISITOR_OUTPUT) || *obj);
  53    }
  54    ok = v->start_struct(v, name, obj, size, errp);
  55    if (obj && (v->type & VISITOR_INPUT)) {
  56        assert(ok != !*obj);
  57    }
  58    return ok;
  59}
  60
  61bool visit_check_struct(Visitor *v, Error **errp)
  62{
  63    trace_visit_check_struct(v);
  64    return v->check_struct ? v->check_struct(v, errp) : true;
  65}
  66
  67void visit_end_struct(Visitor *v, void **obj)
  68{
  69    trace_visit_end_struct(v, obj);
  70    v->end_struct(v, obj);
  71}
  72
  73bool visit_start_list(Visitor *v, const char *name, GenericList **list,
  74                      size_t size, Error **errp)
  75{
  76    bool ok;
  77
  78    assert(!list || size >= sizeof(GenericList));
  79    trace_visit_start_list(v, name, list, size);
  80    ok = v->start_list(v, name, list, size, errp);
  81    if (list && (v->type & VISITOR_INPUT)) {
  82        assert(ok || !*list);
  83    }
  84    return ok;
  85}
  86
  87GenericList *visit_next_list(Visitor *v, GenericList *tail, size_t size)
  88{
  89    assert(tail && size >= sizeof(GenericList));
  90    trace_visit_next_list(v, tail, size);
  91    return v->next_list(v, tail, size);
  92}
  93
  94bool visit_check_list(Visitor *v, Error **errp)
  95{
  96    trace_visit_check_list(v);
  97    return v->check_list ? v->check_list(v, errp) : true;
  98}
  99
 100void visit_end_list(Visitor *v, void **obj)
 101{
 102    trace_visit_end_list(v, obj);
 103    v->end_list(v, obj);
 104}
 105
 106bool visit_start_alternate(Visitor *v, const char *name,
 107                           GenericAlternate **obj, size_t size,
 108                           Error **errp)
 109{
 110    bool ok;
 111
 112    assert(obj && size >= sizeof(GenericAlternate));
 113    assert(!(v->type & VISITOR_OUTPUT) || *obj);
 114    trace_visit_start_alternate(v, name, obj, size);
 115    if (!v->start_alternate) {
 116        assert(!(v->type & VISITOR_INPUT));
 117        return true;
 118    }
 119    ok = v->start_alternate(v, name, obj, size, errp);
 120    if (v->type & VISITOR_INPUT) {
 121        assert(ok != !*obj);
 122    }
 123    return ok;
 124}
 125
 126void visit_end_alternate(Visitor *v, void **obj)
 127{
 128    trace_visit_end_alternate(v, obj);
 129    if (v->end_alternate) {
 130        v->end_alternate(v, obj);
 131    }
 132}
 133
 134bool visit_optional(Visitor *v, const char *name, bool *present)
 135{
 136    trace_visit_optional(v, name, present);
 137    if (v->optional) {
 138        v->optional(v, name, present);
 139    }
 140    return *present;
 141}
 142
 143bool visit_policy_reject(Visitor *v, const char *name,
 144                         unsigned special_features, Error **errp)
 145{
 146    trace_visit_policy_reject(v, name);
 147    if (v->policy_reject) {
 148        return v->policy_reject(v, name, special_features, errp);
 149    }
 150    return false;
 151}
 152
 153bool visit_policy_skip(Visitor *v, const char *name,
 154                       unsigned special_features)
 155{
 156    trace_visit_policy_skip(v, name);
 157    if (v->policy_skip) {
 158        return v->policy_skip(v, name, special_features);
 159    }
 160    return false;
 161}
 162
 163void visit_set_policy(Visitor *v, CompatPolicy *policy)
 164{
 165    v->compat_policy = *policy;
 166}
 167
 168bool visit_is_input(Visitor *v)
 169{
 170    return v->type == VISITOR_INPUT;
 171}
 172
 173bool visit_is_dealloc(Visitor *v)
 174{
 175    return v->type == VISITOR_DEALLOC;
 176}
 177
 178bool visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp)
 179{
 180    assert(obj);
 181    trace_visit_type_int(v, name, obj);
 182    return v->type_int64(v, name, obj, errp);
 183}
 184
 185static bool visit_type_uintN(Visitor *v, uint64_t *obj, const char *name,
 186                             uint64_t max, const char *type, Error **errp)
 187{
 188    uint64_t value = *obj;
 189
 190    assert(v->type == VISITOR_INPUT || value <= max);
 191
 192    if (!v->type_uint64(v, name, &value, errp)) {
 193        return false;
 194    }
 195    if (value > max) {
 196        assert(v->type == VISITOR_INPUT);
 197        error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
 198                   name ? name : "null", type);
 199        return false;
 200    }
 201    *obj = value;
 202    return true;
 203}
 204
 205bool visit_type_uint8(Visitor *v, const char *name, uint8_t *obj,
 206                      Error **errp)
 207{
 208    uint64_t value;
 209    bool ok;
 210
 211    trace_visit_type_uint8(v, name, obj);
 212    value = *obj;
 213    ok = visit_type_uintN(v, &value, name, UINT8_MAX, "uint8_t", errp);
 214    *obj = value;
 215    return ok;
 216}
 217
 218bool visit_type_uint16(Visitor *v, const char *name, uint16_t *obj,
 219                       Error **errp)
 220{
 221    uint64_t value;
 222    bool ok;
 223
 224    trace_visit_type_uint16(v, name, obj);
 225    value = *obj;
 226    ok = visit_type_uintN(v, &value, name, UINT16_MAX, "uint16_t", errp);
 227    *obj = value;
 228    return ok;
 229}
 230
 231bool visit_type_uint32(Visitor *v, const char *name, uint32_t *obj,
 232                       Error **errp)
 233{
 234    uint64_t value;
 235    bool ok;
 236
 237    trace_visit_type_uint32(v, name, obj);
 238    value = *obj;
 239    ok = visit_type_uintN(v, &value, name, UINT32_MAX, "uint32_t", errp);
 240    *obj = value;
 241    return ok;
 242}
 243
 244bool visit_type_uint64(Visitor *v, const char *name, uint64_t *obj,
 245                       Error **errp)
 246{
 247    assert(obj);
 248    trace_visit_type_uint64(v, name, obj);
 249    return v->type_uint64(v, name, obj, errp);
 250}
 251
 252static bool visit_type_intN(Visitor *v, int64_t *obj, const char *name,
 253                            int64_t min, int64_t max, const char *type,
 254                            Error **errp)
 255{
 256    int64_t value = *obj;
 257
 258    assert(v->type == VISITOR_INPUT || (value >= min && value <= max));
 259
 260    if (!v->type_int64(v, name, &value, errp)) {
 261        return false;
 262    }
 263    if (value < min || value > max) {
 264        assert(v->type == VISITOR_INPUT);
 265        error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
 266                   name ? name : "null", type);
 267        return false;
 268    }
 269    *obj = value;
 270    return true;
 271}
 272
 273bool visit_type_int8(Visitor *v, const char *name, int8_t *obj, Error **errp)
 274{
 275    int64_t value;
 276    bool ok;
 277
 278    trace_visit_type_int8(v, name, obj);
 279    value = *obj;
 280    ok = visit_type_intN(v, &value, name, INT8_MIN, INT8_MAX, "int8_t", errp);
 281    *obj = value;
 282    return ok;
 283}
 284
 285bool visit_type_int16(Visitor *v, const char *name, int16_t *obj,
 286                      Error **errp)
 287{
 288    int64_t value;
 289    bool ok;
 290
 291    trace_visit_type_int16(v, name, obj);
 292    value = *obj;
 293    ok = visit_type_intN(v, &value, name, INT16_MIN, INT16_MAX, "int16_t",
 294                         errp);
 295    *obj = value;
 296    return ok;
 297}
 298
 299bool visit_type_int32(Visitor *v, const char *name, int32_t *obj,
 300                      Error **errp)
 301{
 302    int64_t value;
 303    bool ok;
 304
 305    trace_visit_type_int32(v, name, obj);
 306    value = *obj;
 307    ok = visit_type_intN(v, &value, name, INT32_MIN, INT32_MAX, "int32_t",
 308                        errp);
 309    *obj = value;
 310    return ok;
 311}
 312
 313bool visit_type_int64(Visitor *v, const char *name, int64_t *obj,
 314                      Error **errp)
 315{
 316    assert(obj);
 317    trace_visit_type_int64(v, name, obj);
 318    return v->type_int64(v, name, obj, errp);
 319}
 320
 321bool visit_type_size(Visitor *v, const char *name, uint64_t *obj,
 322                     Error **errp)
 323{
 324    assert(obj);
 325    trace_visit_type_size(v, name, obj);
 326    if (v->type_size) {
 327        return v->type_size(v, name, obj, errp);
 328    }
 329    return v->type_uint64(v, name, obj, errp);
 330}
 331
 332bool visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp)
 333{
 334    assert(obj);
 335    trace_visit_type_bool(v, name, obj);
 336    return v->type_bool(v, name, obj, errp);
 337}
 338
 339bool visit_type_str(Visitor *v, const char *name, char **obj, Error **errp)
 340{
 341    bool ok;
 342
 343    assert(obj);
 344    /* TODO: Fix callers to not pass NULL when they mean "", so that we
 345     * can enable:
 346    assert(!(v->type & VISITOR_OUTPUT) || *obj);
 347     */
 348    trace_visit_type_str(v, name, obj);
 349    ok = v->type_str(v, name, obj, errp);
 350    if (v->type & VISITOR_INPUT) {
 351        assert(ok != !*obj);
 352    }
 353    return ok;
 354}
 355
 356bool visit_type_number(Visitor *v, const char *name, double *obj,
 357                       Error **errp)
 358{
 359    assert(obj);
 360    trace_visit_type_number(v, name, obj);
 361    return v->type_number(v, name, obj, errp);
 362}
 363
 364bool visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp)
 365{
 366    bool ok;
 367
 368    assert(obj);
 369    assert(v->type != VISITOR_OUTPUT || *obj);
 370    trace_visit_type_any(v, name, obj);
 371    ok = v->type_any(v, name, obj, errp);
 372    if (v->type == VISITOR_INPUT) {
 373        assert(ok != !*obj);
 374    }
 375    return ok;
 376}
 377
 378bool visit_type_null(Visitor *v, const char *name, QNull **obj,
 379                     Error **errp)
 380{
 381    trace_visit_type_null(v, name, obj);
 382    return v->type_null(v, name, obj, errp);
 383}
 384
 385static bool output_type_enum(Visitor *v, const char *name, int *obj,
 386                             const QEnumLookup *lookup, Error **errp)
 387{
 388    int value = *obj;
 389    char *enum_str;
 390
 391    enum_str = (char *)qapi_enum_lookup(lookup, value);
 392    return visit_type_str(v, name, &enum_str, errp);
 393}
 394
 395static bool input_type_enum(Visitor *v, const char *name, int *obj,
 396                            const QEnumLookup *lookup, Error **errp)
 397{
 398    int64_t value;
 399    g_autofree char *enum_str = NULL;
 400
 401    if (!visit_type_str(v, name, &enum_str, errp)) {
 402        return false;
 403    }
 404
 405    value = qapi_enum_parse(lookup, enum_str, -1, NULL);
 406    if (value < 0) {
 407        error_setg(errp, "Parameter '%s' does not accept value '%s'",
 408                   name ? name : "null", enum_str);
 409        return false;
 410    }
 411
 412    if (lookup->special_features
 413        && !compat_policy_input_ok(lookup->special_features[value],
 414                                   &v->compat_policy,
 415                                   ERROR_CLASS_GENERIC_ERROR,
 416                                   "value", enum_str, errp)) {
 417        return false;
 418    }
 419
 420    *obj = value;
 421    return true;
 422}
 423
 424bool visit_type_enum(Visitor *v, const char *name, int *obj,
 425                     const QEnumLookup *lookup, Error **errp)
 426{
 427    assert(obj && lookup);
 428    trace_visit_type_enum(v, name, obj);
 429    switch (v->type) {
 430    case VISITOR_INPUT:
 431        return input_type_enum(v, name, obj, lookup, errp);
 432    case VISITOR_OUTPUT:
 433        return output_type_enum(v, name, obj, lookup, errp);
 434    case VISITOR_CLONE:
 435        /* nothing further to do, scalar value was already copied by
 436         * g_memdup() during visit_start_*() */
 437        return true;
 438    case VISITOR_DEALLOC:
 439        /* nothing to deallocate for a scalar */
 440        return true;
 441    default:
 442        abort();
 443    }
 444}
 445