qapi/qapi-visit-core.c

   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/error.h"
  17 #include "qapi/qmp/qerror.h"
  18 #include "qapi/visitor.h"
  19 #include "qapi/visitor-impl.h"
  20 #include "trace.h"
  21
  22 /* Zero-initialization must result in default policy */
  23 QEMU_BUILD_BUG_ON(COMPAT_POLICY_INPUT_ACCEPT || COMPAT_POLICY_OUTPUT_ACCEPT);
  24
  25
  26 void visit_complete(Visitor *v, void *opaque)
  27 {
  28     assert(v->type != VISITOR_OUTPUT || v->complete);
  29     trace_visit_complete(v, opaque);
  30     if (v->complete) {
  31         v->complete(v, opaque);
  32     }
  33 }
  34
  35 void visit_free(Visitor *v)
  36 {
  37     trace_visit_free(v);
  38     if (v) {
  39         v->free(v);
  40     }
  41 }
  42
  43 bool visit_start_struct(Visitor *v, const char *name, void **obj,
  44                         size_t size, Error **errp)
  45 {
  46     bool ok;
  47
  48     trace_visit_start_struct(v, name, obj, size);
  49     if (obj) {
  50         assert(size);
  51         assert(!(v->type & VISITOR_OUTPUT) || *obj);
  52     }
  53     ok = v->start_struct(v, name, obj, size, errp);
  54     if (obj && (v->type & VISITOR_INPUT)) {
  55         assert(ok != !*obj);
  56     }
  57     return ok;
  58 }
  59
  60 bool visit_check_struct(Visitor *v, Error **errp)
  61 {
  62     trace_visit_check_struct(v);
  63     return v->check_struct ? v->check_struct(v, errp) : true;
  64 }
  65
  66 void visit_end_struct(Visitor *v, void **obj)
  67 {
  68     trace_visit_end_struct(v, obj);
  69     v->end_struct(v, obj);
  70 }
  71
  72 bool visit_start_list(Visitor *v, const char *name, GenericList **list,
  73                       size_t size, Error **errp)
  74 {
  75     bool ok;
  76
  77     assert(!list || size >= sizeof(GenericList));
  78     trace_visit_start_list(v, name, list, size);
  79     ok = v->start_list(v, name, list, size, errp);
  80     if (list && (v->type & VISITOR_INPUT)) {
  81         assert(ok || !*list);
  82     }
  83     return ok;
  84 }
  85
  86 GenericList *visit_next_list(Visitor *v, GenericList *tail, size_t size)
  87 {
  88     assert(tail && size >= sizeof(GenericList));
  89     trace_visit_next_list(v, tail, size);
  90     return v->next_list(v, tail, size);
  91 }
  92
  93 bool visit_check_list(Visitor *v, Error **errp)
  94 {
  95     trace_visit_check_list(v);
  96     return v->check_list ? v->check_list(v, errp) : true;
  97 }
  98
  99 void visit_end_list(Visitor *v, void **obj)
 100 {
 101     trace_visit_end_list(v, obj);
 102     v->end_list(v, obj);
 103 }
 104
 105 bool visit_start_alternate(Visitor *v, const char *name,
 106                            GenericAlternate **obj, size_t size,
 107                            Error **errp)
 108 {
 109     bool ok;
 110
 111     assert(obj && size >= sizeof(GenericAlternate));
 112     assert(!(v->type & VISITOR_OUTPUT) || *obj);
 113     trace_visit_start_alternate(v, name, obj, size);
 114     if (!v->start_alternate) {
 115         assert(!(v->type & VISITOR_INPUT));
 116         return true;
 117     }
 118     ok = v->start_alternate(v, name, obj, size, errp);
 119     if (v->type & VISITOR_INPUT) {
 120         assert(ok != !*obj);
 121     }
 122     return ok;
 123 }
 124
 125 void visit_end_alternate(Visitor *v, void **obj)
 126 {
 127     trace_visit_end_alternate(v, obj);
 128     if (v->end_alternate) {
 129         v->end_alternate(v, obj);
 130     }
 131 }
 132
 133 bool visit_optional(Visitor *v, const char *name, bool *present)
 134 {
 135     trace_visit_optional(v, name, present);
 136     if (v->optional) {
 137         v->optional(v, name, present);
 138     }
 139     return *present;
 140 }
 141
 142 bool visit_deprecated_accept(Visitor *v, const char *name, Error **errp)
 143 {
 144     trace_visit_deprecated_accept(v, name);
 145     if (v->deprecated_accept) {
 146         return v->deprecated_accept(v, name, errp);
 147     }
 148     return true;
 149 }
 150
 151 bool visit_deprecated(Visitor *v, const char *name)
 152 {
 153     trace_visit_deprecated(v, name);
 154     if (v->deprecated) {
 155         return v->deprecated(v, name);
 156     }
 157     return true;
 158 }
 159
 160 void visit_set_policy(Visitor *v, CompatPolicy *policy)
 161 {
 162     v->compat_policy = *policy;
 163 }
 164
 165 bool visit_is_input(Visitor *v)
 166 {
 167     return v->type == VISITOR_INPUT;
 168 }
 169
 170 bool visit_is_dealloc(Visitor *v)
 171 {
 172     return v->type == VISITOR_DEALLOC;
 173 }
 174
 175 bool visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp)
 176 {
 177     assert(obj);
 178     trace_visit_type_int(v, name, obj);
 179     return v->type_int64(v, name, obj, errp);
 180 }
 181
 182 static bool visit_type_uintN(Visitor *v, uint64_t *obj, const char *name,
 183                              uint64_t max, const char *type, Error **errp)
 184 {
 185     uint64_t value = *obj;
 186
 187     assert(v->type == VISITOR_INPUT || value <= max);
 188
 189     if (!v->type_uint64(v, name, &value, errp)) {
 190         return false;
 191     }
 192     if (value > max) {
 193         assert(v->type == VISITOR_INPUT);
 194         error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
 195                    name ? name : "null", type);
 196         return false;
 197     }
 198     *obj = value;
 199     return true;
 200 }
 201
 202 bool visit_type_uint8(Visitor *v, const char *name, uint8_t *obj,
 203                       Error **errp)
 204 {
 205     uint64_t value;
 206     bool ok;
 207
 208     trace_visit_type_uint8(v, name, obj);
 209     value = *obj;
 210     ok = visit_type_uintN(v, &value, name, UINT8_MAX, "uint8_t", errp);
 211     *obj = value;
 212     return ok;
 213 }
 214
 215 bool visit_type_uint16(Visitor *v, const char *name, uint16_t *obj,
 216                        Error **errp)
 217 {
 218     uint64_t value;
 219     bool ok;
 220
 221     trace_visit_type_uint16(v, name, obj);
 222     value = *obj;
 223     ok = visit_type_uintN(v, &value, name, UINT16_MAX, "uint16_t", errp);
 224     *obj = value;
 225     return ok;
 226 }
 227
 228 bool visit_type_uint32(Visitor *v, const char *name, uint32_t *obj,
 229                        Error **errp)
 230 {
 231     uint64_t value;
 232     bool ok;
 233
 234     trace_visit_type_uint32(v, name, obj);
 235     value = *obj;
 236     ok = visit_type_uintN(v, &value, name, UINT32_MAX, "uint32_t", errp);
 237     *obj = value;
 238     return ok;
 239 }
 240
 241 bool visit_type_uint64(Visitor *v, const char *name, uint64_t *obj,
 242                        Error **errp)
 243 {
 244     assert(obj);
 245     trace_visit_type_uint64(v, name, obj);
 246     return v->type_uint64(v, name, obj, errp);
 247 }
 248
 249 static bool visit_type_intN(Visitor *v, int64_t *obj, const char *name,
 250                             int64_t min, int64_t max, const char *type,
 251                             Error **errp)
 252 {
 253     int64_t value = *obj;
 254
 255     assert(v->type == VISITOR_INPUT || (value >= min && value <= max));
 256
 257     if (!v->type_int64(v, name, &value, errp)) {
 258         return false;
 259     }
 260     if (value < min || value > max) {
 261         assert(v->type == VISITOR_INPUT);
 262         error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
 263                    name ? name : "null", type);
 264         return false;
 265     }
 266     *obj = value;
 267     return true;
 268 }
 269
 270 bool visit_type_int8(Visitor *v, const char *name, int8_t *obj, Error **errp)
 271 {
 272     int64_t value;
 273     bool ok;
 274
 275     trace_visit_type_int8(v, name, obj);
 276     value = *obj;
 277     ok = visit_type_intN(v, &value, name, INT8_MIN, INT8_MAX, "int8_t", errp);
 278     *obj = value;
 279     return ok;
 280 }
 281
 282 bool visit_type_int16(Visitor *v, const char *name, int16_t *obj,
 283                       Error **errp)
 284 {
 285     int64_t value;
 286     bool ok;
 287
 288     trace_visit_type_int16(v, name, obj);
 289     value = *obj;
 290     ok = visit_type_intN(v, &value, name, INT16_MIN, INT16_MAX, "int16_t",
 291                          errp);
 292     *obj = value;
 293     return ok;
 294 }
 295
 296 bool visit_type_int32(Visitor *v, const char *name, int32_t *obj,
 297                       Error **errp)
 298 {
 299     int64_t value;
 300     bool ok;
 301
 302     trace_visit_type_int32(v, name, obj);
 303     value = *obj;
 304     ok = visit_type_intN(v, &value, name, INT32_MIN, INT32_MAX, "int32_t",
 305                         errp);
 306     *obj = value;
 307     return ok;
 308 }
 309
 310 bool visit_type_int64(Visitor *v, const char *name, int64_t *obj,
 311                       Error **errp)
 312 {
 313     assert(obj);
 314     trace_visit_type_int64(v, name, obj);
 315     return v->type_int64(v, name, obj, errp);
 316 }
 317
 318 bool visit_type_size(Visitor *v, const char *name, uint64_t *obj,
 319                      Error **errp)
 320 {
 321     assert(obj);
 322     trace_visit_type_size(v, name, obj);
 323     if (v->type_size) {
 324         return v->type_size(v, name, obj, errp);
 325     }
 326     return v->type_uint64(v, name, obj, errp);
 327 }
 328
 329 bool visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp)
 330 {
 331     assert(obj);
 332     trace_visit_type_bool(v, name, obj);
 333     return v->type_bool(v, name, obj, errp);
 334 }
 335
 336 bool visit_type_str(Visitor *v, const char *name, char **obj, Error **errp)
 337 {
 338     bool ok;
 339
 340     assert(obj);
 341     /* TODO: Fix callers to not pass NULL when they mean "", so that we
 342      * can enable:
 343     assert(!(v->type & VISITOR_OUTPUT) || *obj);
 344      */
 345     trace_visit_type_str(v, name, obj);
 346     ok = v->type_str(v, name, obj, errp);
 347     if (v->type & VISITOR_INPUT) {
 348         assert(ok != !*obj);
 349     }
 350     return ok;
 351 }
 352
 353 bool visit_type_number(Visitor *v, const char *name, double *obj,
 354                        Error **errp)
 355 {
 356     assert(obj);
 357     trace_visit_type_number(v, name, obj);
 358     return v->type_number(v, name, obj, errp);
 359 }
 360
 361 bool visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp)
 362 {
 363     bool ok;
 364
 365     assert(obj);
 366     assert(v->type != VISITOR_OUTPUT || *obj);
 367     trace_visit_type_any(v, name, obj);
 368     ok = v->type_any(v, name, obj, errp);
 369     if (v->type == VISITOR_INPUT) {
 370         assert(ok != !*obj);
 371     }
 372     return ok;
 373 }
 374
 375 bool visit_type_null(Visitor *v, const char *name, QNull **obj,
 376                      Error **errp)
 377 {
 378     trace_visit_type_null(v, name, obj);
 379     return v->type_null(v, name, obj, errp);
 380 }
 381
 382 static bool output_type_enum(Visitor *v, const char *name, int *obj,
 383                              const QEnumLookup *lookup, Error **errp)
 384 {
 385     int value = *obj;
 386     char *enum_str;
 387
 388     enum_str = (char *)qapi_enum_lookup(lookup, value);
 389     return visit_type_str(v, name, &enum_str, errp);
 390 }
 391
 392 static bool input_type_enum(Visitor *v, const char *name, int *obj,
 393                             const QEnumLookup *lookup, Error **errp)
 394 {
 395     int64_t value;
 396     g_autofree char *enum_str = NULL;
 397
 398     if (!visit_type_str(v, name, &enum_str, errp)) {
 399         return false;
 400     }
 401
 402     value = qapi_enum_parse(lookup, enum_str, -1, NULL);
 403     if (value < 0) {
 404         error_setg(errp, "Parameter '%s' does not accept value '%s'",
 405                    name ? name : "null", enum_str);
 406         return false;
 407     }
 408
 409     if (lookup->flags && (lookup->flags[value] & QAPI_ENUM_DEPRECATED)) {
 410         switch (v->compat_policy.deprecated_input) {
 411         case COMPAT_POLICY_INPUT_ACCEPT:
 412             break;
 413         case COMPAT_POLICY_INPUT_REJECT:
 414             error_setg(errp, "Deprecated value '%s' disabled by policy",
 415                        enum_str);
 416             return false;
 417         case COMPAT_POLICY_INPUT_CRASH:
 418         default:
 419             abort();
 420         }
 421     }
 422
 423     *obj = value;
 424     return true;
 425 }
 426
 427 bool visit_type_enum(Visitor *v, const char *name, int *obj,
 428                      const QEnumLookup *lookup, Error **errp)
 429 {
 430     assert(obj && lookup);
 431     trace_visit_type_enum(v, name, obj);
 432     switch (v->type) {
 433     case VISITOR_INPUT:
 434         return input_type_enum(v, name, obj, lookup, errp);
 435     case VISITOR_OUTPUT:
 436         return output_type_enum(v, name, obj, lookup, errp);
 437     case VISITOR_CLONE:
 438         /* nothing further to do, scalar value was already copied by
 439          * g_memdup() during visit_start_*() */
 440         return true;
 441     case VISITOR_DEALLOC:
 442         /* nothing to deallocate for a scalar */
 443         return true;
 444     default:
 445         abort();
 446     }
 447 }