qerror.c

   1 /*
   2  * QError Module
   3  *
   4  * Copyright (C) 2009 Red Hat Inc.
   5  *
   6  * Authors:
   7  *  Luiz Capitulino <lcapitulino@redhat.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 #include "monitor.h"
  14 #include "qjson.h"
  15 #include "qerror.h"
  16 #include "qemu-common.h"
  17
  18 static void qerror_destroy_obj(QObject *obj);
  19
  20 static const QType qerror_type = {
  21     .code = QTYPE_QERROR,
  22     .destroy = qerror_destroy_obj,
  23 };
  24
  25 /**
  26  * The 'desc' parameter is a printf-like string, the format of the format
  27  * string is:
  28  *
  29  * %(KEY)
  30  *
  31  * Where KEY is a QDict key, which has to be passed to qerror_from_info().
  32  *
  33  * Example:
  34  *
  35  * "foo error on device: %(device) slot: %(slot_nr)"
  36  *
  37  * A single percent sign can be printed if followed by a second one,
  38  * for example:
  39  *
  40  * "running out of foo: %(foo)%%"
  41  *
  42  * Please keep the entries in alphabetical order.
  43  * Use scripts/check-qerror.sh to check.
  44  */
  45 static const QErrorStringTable qerror_table[] = {
  46     {
  47          QERR_ADD_CLIENT_FAILED,
  48          "Could not add client",
  49     },
  50     {
  51          QERR_AMBIGUOUS_PATH,
  52          "Path '%(path)' does not uniquely identify an object"
  53     },
  54     {
  55          QERR_BAD_BUS_FOR_DEVICE,
  56          "Device '%(device)' can't go on a %(bad_bus_type) bus",
  57     },
  58     {
  59          QERR_BASE_NOT_FOUND,
  60          "Base '%(base)' not found",
  61     },
  62     {
  63          QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
  64          "Block format '%(format)' used by device '%(name)' does not support feature '%(feature)'",
  65     },
  66     {
  67          QERR_BUS_NO_HOTPLUG,
  68          "Bus '%(bus)' does not support hotplugging",
  69     },
  70     {
  71          QERR_BUS_NOT_FOUND,
  72          "Bus '%(bus)' not found",
  73     },
  74     {
  75          QERR_COMMAND_DISABLED,
  76          "The command %(name) has been disabled for this instance",
  77     },
  78     {
  79          QERR_COMMAND_NOT_FOUND,
  80          "The command %(name) has not been found",
  81     },
  82     {
  83          QERR_DEVICE_ENCRYPTED,
  84          "'%(device)' (%(filename)) is encrypted",
  85     },
  86     {
  87          QERR_DEVICE_FEATURE_BLOCKS_MIGRATION,
  88          "Migration is disabled when using feature '%(feature)' in device '%(device)'",
  89     },
  90     {
  91          QERR_DEVICE_HAS_NO_MEDIUM,
  92          "Device '%(device)' has no medium",
  93     },
  94     {
  95          QERR_DEVICE_INIT_FAILED,
  96          "Device '%(device)' could not be initialized",
  97     },
  98     {
  99          QERR_DEVICE_IN_USE,
 100          "Device '%(device)' is in use",
 101     },
 102     {
 103          QERR_DEVICE_IS_READ_ONLY,
 104          "Device '%(device)' is read only",
 105     },
 106     {
 107          QERR_DEVICE_LOCKED,
 108          "Device '%(device)' is locked",
 109     },
 110     {
 111          QERR_DEVICE_MULTIPLE_BUSSES,
 112          "Device '%(device)' has multiple child busses",
 113     },
 114     {
 115          QERR_DEVICE_NO_BUS,
 116          "Device '%(device)' has no child bus",
 117     },
 118     {
 119          QERR_DEVICE_NO_HOTPLUG,
 120          "Device '%(device)' does not support hotplugging",
 121     },
 122     {
 123          QERR_DEVICE_NOT_ACTIVE,
 124          "Device '%(device)' has not been activated",
 125     },
 126     {
 127          QERR_DEVICE_NOT_ENCRYPTED,
 128          "Device '%(device)' is not encrypted",
 129     },
 130     {
 131          QERR_DEVICE_NOT_FOUND,
 132          "Device '%(device)' not found",
 133     },
 134     {
 135          QERR_DEVICE_NOT_REMOVABLE,
 136          "Device '%(device)' is not removable",
 137     },
 138     {
 139          QERR_DUPLICATE_ID,
 140          "Duplicate ID '%(id)' for %(object)",
 141     },
 142     {
 143          QERR_FD_NOT_FOUND,
 144          "File descriptor named '%(name)' not found",
 145     },
 146     {
 147          QERR_FD_NOT_SUPPLIED,
 148          "No file descriptor supplied via SCM_RIGHTS",
 149     },
 150     {
 151          QERR_FEATURE_DISABLED,
 152          "The feature '%(name)' is not enabled",
 153     },
 154     {
 155          QERR_INVALID_BLOCK_FORMAT,
 156          "Invalid block format '%(name)'",
 157     },
 158     {
 159          QERR_INVALID_OPTION_GROUP,
 160          "There is no option group '%(group)'",
 161     },
 162     {
 163          QERR_INVALID_PARAMETER,
 164          "Invalid parameter '%(name)'",
 165     },
 166     {
 167          QERR_INVALID_PARAMETER_COMBINATION,
 168          "Invalid parameter combination",
 169     },
 170     {
 171          QERR_INVALID_PARAMETER_TYPE,
 172          "Invalid parameter type for '%(name)', expected: %(expected)",
 173     },
 174     {
 175          QERR_INVALID_PARAMETER_VALUE,
 176          "Parameter '%(name)' expects %(expected)",
 177     },
 178     {
 179          QERR_INVALID_PASSWORD,
 180          "Password incorrect",
 181     },
 182     {
 183          QERR_IO_ERROR,
 184          "An IO error has occurred",
 185     },
 186     {
 187          QERR_JSON_PARSE_ERROR,
 188          "JSON parse error, %(message)",
 189
 190     },
 191     {
 192          QERR_JSON_PARSING,
 193          "Invalid JSON syntax",
 194     },
 195     {
 196          QERR_KVM_MISSING_CAP,
 197          "Using KVM without %(capability), %(feature) unavailable",
 198     },
 199     {
 200          QERR_MIGRATION_ACTIVE,
 201          "There's a migration process in progress",
 202     },
 203     {
 204          QERR_MIGRATION_NOT_SUPPORTED,
 205          "State blocked by non-migratable device '%(device)'",
 206     },
 207     {
 208          QERR_MIGRATION_EXPECTED,
 209          "An incoming migration is expected before this command can be executed",
 210     },
 211     {
 212          QERR_MISSING_PARAMETER,
 213          "Parameter '%(name)' is missing",
 214     },
 215     {
 216          QERR_NO_BUS_FOR_DEVICE,
 217          "No '%(bus)' bus found for device '%(device)'",
 218     },
 219     {
 220          QERR_NOT_SUPPORTED,
 221          "Not supported",
 222     },
 223     {
 224          QERR_OPEN_FILE_FAILED,
 225          "Could not open '%(filename)'",
 226     },
 227     {
 228          QERR_PERMISSION_DENIED,
 229          "Insufficient permission to perform this operation",
 230     },
 231     {
 232          QERR_PROPERTY_NOT_FOUND,
 233          "Property '%(device).%(property)' not found",
 234     },
 235     {
 236          QERR_PROPERTY_VALUE_BAD,
 237          "Property '%(device).%(property)' doesn't take value '%(value)'",
 238     },
 239     {
 240          QERR_PROPERTY_VALUE_IN_USE,
 241          "Property '%(device).%(property)' can't take value '%(value)', it's in use",
 242     },
 243     {
 244          QERR_PROPERTY_VALUE_NOT_FOUND,
 245          "Property '%(device).%(property)' can't find value '%(value)'",
 246     },
 247     {
 248          QERR_PROPERTY_VALUE_NOT_POWER_OF_2,
 249          "Property '%(device).%(property)' doesn't take "
 250                      "value '%(value)', it's not a power of 2",
 251     },
 252     {
 253          QERR_PROPERTY_VALUE_OUT_OF_RANGE,
 254          "Property '%(device).%(property)' doesn't take "
 255                      "value %(value) (minimum: %(min), maximum: %(max))",
 256     },
 257     {
 258          QERR_QGA_COMMAND_FAILED,
 259          "Guest agent command failed, error was '%(message)'",
 260     },
 261     {
 262          QERR_QGA_LOGGING_FAILED,
 263          "Guest agent failed to log non-optional log statement",
 264     },
 265     {
 266          QERR_QMP_BAD_INPUT_OBJECT,
 267          "Expected '%(expected)' in QMP input",
 268     },
 269     {
 270          QERR_QMP_BAD_INPUT_OBJECT_MEMBER,
 271          "QMP input object member '%(member)' expects '%(expected)'",
 272     },
 273     {
 274          QERR_QMP_EXTRA_MEMBER,
 275          "QMP input object member '%(member)' is unexpected",
 276     },
 277     {
 278          QERR_RESET_REQUIRED,
 279          "Resetting the Virtual Machine is required",
 280     },
 281     {
 282          QERR_SET_PASSWD_FAILED,
 283          "Could not set password",
 284     },
 285     {
 286          QERR_TOO_MANY_FILES,
 287          "Too many open files",
 288     },
 289     {
 290          QERR_UNDEFINED_ERROR,
 291          "An undefined error has occurred",
 292     },
 293     {
 294          QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
 295          "'%(device)' uses a %(format) feature which is not "
 296                      "supported by this qemu version: %(feature)",
 297     },
 298     {
 299          QERR_UNSUPPORTED,
 300          "this feature or command is not currently supported",
 301     },
 302     {
 303          QERR_VIRTFS_FEATURE_BLOCKS_MIGRATION,
 304          "Migration is disabled when VirtFS export path '%(path)' "
 305                      "is mounted in the guest using mount_tag '%(tag)'",
 306     },
 307     {
 308          QERR_VNC_SERVER_FAILED,
 309          "Could not start VNC server on %(target)",
 310     },
 311     {
 312          QERR_SOCKET_CONNECT_FAILED,
 313          "Failed to connect to socket",
 314     },
 315     {
 316          QERR_SOCKET_LISTEN_FAILED,
 317          "Failed to set socket to listening mode",
 318     },
 319     {
 320          QERR_SOCKET_BIND_FAILED,
 321          "Failed to bind socket",
 322     },
 323     {
 324          QERR_SOCKET_CREATE_FAILED,
 325          "Failed to create socket",
 326     },
 327     {}
 328 };
 329
 330 /**
 331  * qerror_new(): Create a new QError
 332  *
 333  * Return strong reference.
 334  */
 335 static QError *qerror_new(void)
 336 {
 337     QError *qerr;
 338
 339     qerr = g_malloc0(sizeof(*qerr));
 340     QOBJECT_INIT(qerr, &qerror_type);
 341
 342     return qerr;
 343 }
 344
 345 static QDict *error_obj_from_fmt_no_fail(const char *fmt, va_list *va)
 346 {
 347     QObject *obj;
 348     QDict *ret;
 349
 350     obj = qobject_from_jsonv(fmt, va);
 351     if (!obj) {
 352         fprintf(stderr, "invalid json in error dict '%s'\n", fmt);
 353         abort();
 354     }
 355     if (qobject_type(obj) != QTYPE_QDICT) {
 356         fprintf(stderr, "error is not a dict '%s'\n", fmt);
 357         abort();
 358     }
 359
 360     ret = qobject_to_qdict(obj);
 361     obj = qdict_get(ret, "class");
 362     if (!obj) {
 363         fprintf(stderr, "missing 'class' key in '%s'\n", fmt);
 364         abort();
 365     }
 366     if (qobject_type(obj) != QTYPE_QSTRING) {
 367         fprintf(stderr, "'class' key value should be a string in '%s'\n", fmt);
 368         abort();
 369     }
 370
 371     obj = qdict_get(ret, "data");
 372     if (!obj) {
 373         fprintf(stderr, "missing 'data' key in '%s'\n", fmt);
 374         abort();
 375     }
 376     if (qobject_type(obj) != QTYPE_QDICT) {
 377         fprintf(stderr, "'data' key value should be a dict in '%s'\n", fmt);
 378         abort();
 379     }
 380
 381     return ret;
 382 }
 383
 384 /**
 385  * qerror_from_info(): Create a new QError from error information
 386  *
 387  * Return strong reference.
 388  */
 389 static QError *qerror_from_info(ErrorClass err_class, const char *fmt,
 390                                 va_list *va)
 391 {
 392     QError *qerr;
 393
 394     qerr = qerror_new();
 395     loc_save(&qerr->loc);
 396
 397     qerr->err_class = err_class;
 398     qerr->error = error_obj_from_fmt_no_fail(fmt, va);
 399     qerr->err_msg = qerror_format(fmt, qerr->error);
 400
 401     return qerr;
 402 }
 403
 404 static void parse_error(const QErrorStringTable *entry, int c)
 405 {
 406     fprintf(stderr, "expected '%c' in '%s'", c, entry->desc);
 407     abort();
 408 }
 409
 410 static const char *append_field(QDict *error, QString *outstr,
 411                                 const QErrorStringTable *entry,
 412                                 const char *start)
 413 {
 414     QObject *obj;
 415     QDict *qdict;
 416     QString *key_qs;
 417     const char *end, *key;
 418
 419     if (*start != '%')
 420         parse_error(entry, '%');
 421     start++;
 422     if (*start != '(')
 423         parse_error(entry, '(');
 424     start++;
 425
 426     end = strchr(start, ')');
 427     if (!end)
 428         parse_error(entry, ')');
 429
 430     key_qs = qstring_from_substr(start, 0, end - start - 1);
 431     key = qstring_get_str(key_qs);
 432
 433     qdict = qobject_to_qdict(qdict_get(error, "data"));
 434     obj = qdict_get(qdict, key);
 435     if (!obj) {
 436         abort();
 437     }
 438
 439     switch (qobject_type(obj)) {
 440         case QTYPE_QSTRING:
 441             qstring_append(outstr, qdict_get_str(qdict, key));
 442             break;
 443         case QTYPE_QINT:
 444             qstring_append_int(outstr, qdict_get_int(qdict, key));
 445             break;
 446         default:
 447             abort();
 448     }
 449
 450     QDECREF(key_qs);
 451     return ++end;
 452 }
 453
 454 static QString *qerror_format_desc(QDict *error,
 455                                    const QErrorStringTable *entry)
 456 {
 457     QString *qstring;
 458     const char *p;
 459
 460     assert(entry != NULL);
 461
 462     qstring = qstring_new();
 463
 464     for (p = entry->desc; *p != '\0';) {
 465         if (*p != '%') {
 466             qstring_append_chr(qstring, *p++);
 467         } else if (*(p + 1) == '%') {
 468             qstring_append_chr(qstring, '%');
 469             p += 2;
 470         } else {
 471             p = append_field(error, qstring, entry, p);
 472         }
 473     }
 474
 475     return qstring;
 476 }
 477
 478 char *qerror_format(const char *fmt, QDict *error)
 479 {
 480     const QErrorStringTable *entry = NULL;
 481     QString *qstr;
 482     char *ret;
 483     int i;
 484
 485     for (i = 0; qerror_table[i].error_fmt; i++) {
 486         if (strcmp(qerror_table[i].error_fmt, fmt) == 0) {
 487             entry = &qerror_table[i];
 488             break;
 489         }
 490     }
 491
 492     qstr = qerror_format_desc(error, entry);
 493     ret = g_strdup(qstring_get_str(qstr));
 494     QDECREF(qstr);
 495
 496     return ret;
 497 }
 498
 499 /**
 500  * qerror_human(): Format QError data into human-readable string.
 501  */
 502 QString *qerror_human(const QError *qerror)
 503 {
 504     return qstring_from_str(qerror->err_msg);
 505 }
 506
 507 /**
 508  * qerror_print(): Print QError data
 509  *
 510  * This function will print the member 'desc' of the specified QError object,
 511  * it uses error_report() for this, so that the output is routed to the right
 512  * place (ie. stderr or Monitor's device).
 513  */
 514 static void qerror_print(QError *qerror)
 515 {
 516     QString *qstring = qerror_human(qerror);
 517     loc_push_restore(&qerror->loc);
 518     error_report("%s", qstring_get_str(qstring));
 519     loc_pop(&qerror->loc);
 520     QDECREF(qstring);
 521 }
 522
 523 void qerror_report(ErrorClass eclass, const char *fmt, ...)
 524 {
 525     va_list va;
 526     QError *qerror;
 527
 528     va_start(va, fmt);
 529     qerror = qerror_from_info(eclass, fmt, &va);
 530     va_end(va);
 531
 532     if (monitor_cur_is_qmp()) {
 533         monitor_set_error(cur_mon, qerror);
 534     } else {
 535         qerror_print(qerror);
 536         QDECREF(qerror);
 537     }
 538 }
 539
 540 /* Evil... */
 541 struct Error
 542 {
 543     QDict *obj;
 544     char *msg;
 545     ErrorClass err_class;
 546 };
 547
 548 void qerror_report_err(Error *err)
 549 {
 550     QError *qerr;
 551
 552     qerr = qerror_new();
 553     loc_save(&qerr->loc);
 554     QINCREF(err->obj);
 555     qerr->error = err->obj;
 556     qerr->err_msg = g_strdup(err->msg);
 557     qerr->err_class = err->err_class;
 558
 559     if (monitor_cur_is_qmp()) {
 560         monitor_set_error(cur_mon, qerr);
 561     } else {
 562         qerror_print(qerr);
 563         QDECREF(qerr);
 564     }
 565 }
 566
 567 void assert_no_error(Error *err)
 568 {
 569     if (err) {
 570         qerror_report_err(err);
 571         abort();
 572     }
 573 }
 574
 575 /**
 576  * qobject_to_qerror(): Convert a QObject into a QError
 577  */
 578 static QError *qobject_to_qerror(const QObject *obj)
 579 {
 580     if (qobject_type(obj) != QTYPE_QERROR) {
 581         return NULL;
 582     }
 583
 584     return container_of(obj, QError, base);
 585 }
 586
 587 /**
 588  * qerror_destroy_obj(): Free all memory allocated by a QError
 589  */
 590 static void qerror_destroy_obj(QObject *obj)
 591 {
 592     QError *qerr;
 593
 594     assert(obj != NULL);
 595     qerr = qobject_to_qerror(obj);
 596
 597     QDECREF(qerr->error);
 598     g_free(qerr->err_msg);
 599     g_free(qerr);
 600 }