util/qemu-option.c

   1 /*
   2  * Commandline option parsing functions
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  * Copyright (c) 2009 Kevin Wolf <kwolf@redhat.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27
  28 #include "qapi/error.h"
  29 #include "qemu/error-report.h"
  30 #include "qapi/qmp/qbool.h"
  31 #include "qapi/qmp/qdict.h"
  32 #include "qapi/qmp/qnum.h"
  33 #include "qapi/qmp/qstring.h"
  34 #include "qapi/qmp/qerror.h"
  35 #include "qemu/option_int.h"
  36 #include "qemu/cutils.h"
  37 #include "qemu/id.h"
  38 #include "qemu/help_option.h"
  39
  40 /*
  41  * Extracts the name of an option from the parameter string (@p points at the
  42  * first byte of the option name)
  43  *
  44  * The option name is @len characters long and is copied into @option. The
  45  * caller is responsible for free'ing @option when no longer required.
  46  *
  47  * The return value is the position of the delimiter/zero byte after the option
  48  * name in @p.
  49  */
  50 static const char *get_opt_name(const char *p, char **option, size_t len)
  51 {
  52     *option = g_strndup(p, len);
  53     return p + len;
  54 }
  55
  56 /*
  57  * Extracts the value of an option from the parameter string p (p points at the
  58  * first byte of the option value)
  59  *
  60  * This function is comparable to get_opt_name with the difference that the
  61  * delimiter is fixed to be comma which starts a new option. To specify an
  62  * option value that contains commas, double each comma.
  63  */
  64 const char *get_opt_value(const char *p, char **value)
  65 {
  66     size_t capacity = 0, length;
  67     const char *offset;
  68
  69     *value = NULL;
  70     while (1) {
  71         offset = qemu_strchrnul(p, ',');
  72         length = offset - p;
  73         if (*offset != '\0' && *(offset + 1) == ',') {
  74             length++;
  75         }
  76         *value = g_renew(char, *value, capacity + length + 1);
  77         strncpy(*value + capacity, p, length);
  78         (*value)[capacity + length] = '\0';
  79         capacity += length;
  80         if (*offset == '\0' ||
  81             *(offset + 1) != ',') {
  82             break;
  83         }
  84
  85         p += (offset - p) + 2;
  86     }
  87
  88     return offset;
  89 }
  90
  91 static bool parse_option_number(const char *name, const char *value,
  92                                 uint64_t *ret, Error **errp)
  93 {
  94     uint64_t number;
  95     int err;
  96
  97     err = qemu_strtou64(value, NULL, 0, &number);
  98     if (err == -ERANGE) {
  99         error_setg(errp, "Value '%s' is too large for parameter '%s'",
 100                    value, name);
 101         return false;
 102     }
 103     if (err) {
 104         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
 105         return false;
 106     }
 107     *ret = number;
 108     return true;
 109 }
 110
 111 static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
 112                                             const char *name)
 113 {
 114     int i;
 115
 116     for (i = 0; desc[i].name != NULL; i++) {
 117         if (strcmp(desc[i].name, name) == 0) {
 118             return &desc[i];
 119         }
 120     }
 121
 122     return NULL;
 123 }
 124
 125 static const char *find_default_by_name(QemuOpts *opts, const char *name)
 126 {
 127     const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
 128
 129     return desc ? desc->def_value_str : NULL;
 130 }
 131
 132 bool parse_option_size(const char *name, const char *value,
 133                        uint64_t *ret, Error **errp)
 134 {
 135     uint64_t size;
 136     int err;
 137
 138     err = qemu_strtosz(value, NULL, &size);
 139     if (err == -ERANGE) {
 140         error_setg(errp, "Value '%s' is out of range for parameter '%s'",
 141                    value, name);
 142         return false;
 143     }
 144     if (err) {
 145         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
 146                    "a non-negative number below 2^64");
 147         error_append_hint(errp, "Optional suffix k, M, G, T, P or E means"
 148                           " kilo-, mega-, giga-, tera-, peta-\n"
 149                           "and exabytes, respectively.\n");
 150         return false;
 151     }
 152     *ret = size;
 153     return true;
 154 }
 155
 156 static const char *opt_type_to_string(enum QemuOptType type)
 157 {
 158     switch (type) {
 159     case QEMU_OPT_STRING:
 160         return "str";
 161     case QEMU_OPT_BOOL:
 162         return "bool (on/off)";
 163     case QEMU_OPT_NUMBER:
 164         return "num";
 165     case QEMU_OPT_SIZE:
 166         return "size";
 167     }
 168
 169     g_assert_not_reached();
 170 }
 171
 172 /**
 173  * Print the list of options available in the given list.  If
 174  * @print_caption is true, a caption (including the list name, if it
 175  * exists) is printed.  The options itself will be indented, so
 176  * @print_caption should only be set to false if the caller prints its
 177  * own custom caption (so that the indentation makes sense).
 178  */
 179 void qemu_opts_print_help(QemuOptsList *list, bool print_caption)
 180 {
 181     QemuOptDesc *desc;
 182     int i;
 183     GPtrArray *array = g_ptr_array_new();
 184
 185     assert(list);
 186     desc = list->desc;
 187     while (desc && desc->name) {
 188         GString *str = g_string_new(NULL);
 189         g_string_append_printf(str, "  %s=<%s>", desc->name,
 190                                opt_type_to_string(desc->type));
 191         if (desc->help) {
 192             if (str->len < 24) {
 193                 g_string_append_printf(str, "%*s", 24 - (int)str->len, "");
 194             }
 195             g_string_append_printf(str, " - %s", desc->help);
 196         }
 197         g_ptr_array_add(array, g_string_free(str, false));
 198         desc++;
 199     }
 200
 201     g_ptr_array_sort(array, (GCompareFunc)qemu_pstrcmp0);
 202     if (print_caption && array->len > 0) {
 203         if (list->name) {
 204             printf("%s options:\n", list->name);
 205         } else {
 206             printf("Options:\n");
 207         }
 208     } else if (array->len == 0) {
 209         if (list->name) {
 210             printf("There are no options for %s.\n", list->name);
 211         } else {
 212             printf("No options available.\n");
 213         }
 214     }
 215     for (i = 0; i < array->len; i++) {
 216         printf("%s\n", (char *)array->pdata[i]);
 217     }
 218     g_ptr_array_set_free_func(array, g_free);
 219     g_ptr_array_free(array, true);
 220
 221 }
 222 /* ------------------------------------------------------------------ */
 223
 224 QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
 225 {
 226     QemuOpt *opt;
 227
 228     QTAILQ_FOREACH_REVERSE(opt, &opts->head, next) {
 229         if (strcmp(opt->name, name) != 0)
 230             continue;
 231         return opt;
 232     }
 233     return NULL;
 234 }
 235
 236 static void qemu_opt_del(QemuOpt *opt)
 237 {
 238     QTAILQ_REMOVE(&opt->opts->head, opt, next);
 239     g_free(opt->name);
 240     g_free(opt->str);
 241     g_free(opt);
 242 }
 243
 244 /* qemu_opt_set allows many settings for the same option.
 245  * This function deletes all settings for an option.
 246  */
 247 static void qemu_opt_del_all(QemuOpts *opts, const char *name)
 248 {
 249     QemuOpt *opt, *next_opt;
 250
 251     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next_opt) {
 252         if (!strcmp(opt->name, name)) {
 253             qemu_opt_del(opt);
 254         }
 255     }
 256 }
 257
 258 const char *qemu_opt_get(QemuOpts *opts, const char *name)
 259 {
 260     QemuOpt *opt;
 261
 262     if (opts == NULL) {
 263         return NULL;
 264     }
 265
 266     opt = qemu_opt_find(opts, name);
 267     if (!opt) {
 268         return find_default_by_name(opts, name);
 269     }
 270
 271     return opt->str;
 272 }
 273
 274 void qemu_opt_iter_init(QemuOptsIter *iter, QemuOpts *opts, const char *name)
 275 {
 276     iter->opts = opts;
 277     iter->opt = QTAILQ_FIRST(&opts->head);
 278     iter->name = name;
 279 }
 280
 281 const char *qemu_opt_iter_next(QemuOptsIter *iter)
 282 {
 283     QemuOpt *ret = iter->opt;
 284     if (iter->name) {
 285         while (ret && !g_str_equal(iter->name, ret->name)) {
 286             ret = QTAILQ_NEXT(ret, next);
 287         }
 288     }
 289     iter->opt = ret ? QTAILQ_NEXT(ret, next) : NULL;
 290     return ret ? ret->str : NULL;
 291 }
 292
 293 /* Get a known option (or its default) and remove it from the list
 294  * all in one action. Return a malloced string of the option value.
 295  * Result must be freed by caller with g_free().
 296  */
 297 char *qemu_opt_get_del(QemuOpts *opts, const char *name)
 298 {
 299     QemuOpt *opt;
 300     char *str;
 301
 302     if (opts == NULL) {
 303         return NULL;
 304     }
 305
 306     opt = qemu_opt_find(opts, name);
 307     if (!opt) {
 308         return g_strdup(find_default_by_name(opts, name));
 309     }
 310     str = opt->str;
 311     opt->str = NULL;
 312     qemu_opt_del_all(opts, name);
 313     return str;
 314 }
 315
 316 bool qemu_opt_has_help_opt(QemuOpts *opts)
 317 {
 318     QemuOpt *opt;
 319
 320     QTAILQ_FOREACH_REVERSE(opt, &opts->head, next) {
 321         if (is_help_option(opt->name)) {
 322             return true;
 323         }
 324     }
 325     return false;
 326 }
 327
 328 static bool qemu_opt_get_bool_helper(QemuOpts *opts, const char *name,
 329                                      bool defval, bool del)
 330 {
 331     QemuOpt *opt;
 332     const char *def_val;
 333     bool ret = defval;
 334
 335     if (opts == NULL) {
 336         return ret;
 337     }
 338
 339     opt = qemu_opt_find(opts, name);
 340     if (opt == NULL) {
 341         def_val = find_default_by_name(opts, name);
 342         if (def_val) {
 343             qapi_bool_parse(name, def_val, &ret, &error_abort);
 344         }
 345         return ret;
 346     }
 347     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
 348     ret = opt->value.boolean;
 349     if (del) {
 350         qemu_opt_del_all(opts, name);
 351     }
 352     return ret;
 353 }
 354
 355 bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
 356 {
 357     return qemu_opt_get_bool_helper(opts, name, defval, false);
 358 }
 359
 360 bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
 361 {
 362     return qemu_opt_get_bool_helper(opts, name, defval, true);
 363 }
 364
 365 static uint64_t qemu_opt_get_number_helper(QemuOpts *opts, const char *name,
 366                                            uint64_t defval, bool del)
 367 {
 368     QemuOpt *opt;
 369     const char *def_val;
 370     uint64_t ret = defval;
 371
 372     if (opts == NULL) {
 373         return ret;
 374     }
 375
 376     opt = qemu_opt_find(opts, name);
 377     if (opt == NULL) {
 378         def_val = find_default_by_name(opts, name);
 379         if (def_val) {
 380             parse_option_number(name, def_val, &ret, &error_abort);
 381         }
 382         return ret;
 383     }
 384     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
 385     ret = opt->value.uint;
 386     if (del) {
 387         qemu_opt_del_all(opts, name);
 388     }
 389     return ret;
 390 }
 391
 392 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
 393 {
 394     return qemu_opt_get_number_helper(opts, name, defval, false);
 395 }
 396
 397 uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
 398                                  uint64_t defval)
 399 {
 400     return qemu_opt_get_number_helper(opts, name, defval, true);
 401 }
 402
 403 static uint64_t qemu_opt_get_size_helper(QemuOpts *opts, const char *name,
 404                                          uint64_t defval, bool del)
 405 {
 406     QemuOpt *opt;
 407     const char *def_val;
 408     uint64_t ret = defval;
 409
 410     if (opts == NULL) {
 411         return ret;
 412     }
 413
 414     opt = qemu_opt_find(opts, name);
 415     if (opt == NULL) {
 416         def_val = find_default_by_name(opts, name);
 417         if (def_val) {
 418             parse_option_size(name, def_val, &ret, &error_abort);
 419         }
 420         return ret;
 421     }
 422     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
 423     ret = opt->value.uint;
 424     if (del) {
 425         qemu_opt_del_all(opts, name);
 426     }
 427     return ret;
 428 }
 429
 430 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
 431 {
 432     return qemu_opt_get_size_helper(opts, name, defval, false);
 433 }
 434
 435 uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
 436                                uint64_t defval)
 437 {
 438     return qemu_opt_get_size_helper(opts, name, defval, true);
 439 }
 440
 441 static bool qemu_opt_parse(QemuOpt *opt, Error **errp)
 442 {
 443     if (opt->desc == NULL)
 444         return true;
 445
 446     switch (opt->desc->type) {
 447     case QEMU_OPT_STRING:
 448         /* nothing */
 449         return true;
 450     case QEMU_OPT_BOOL:
 451         return qapi_bool_parse(opt->name, opt->str, &opt->value.boolean, errp);
 452     case QEMU_OPT_NUMBER:
 453         return parse_option_number(opt->name, opt->str, &opt->value.uint,
 454                                    errp);
 455     case QEMU_OPT_SIZE:
 456         return parse_option_size(opt->name, opt->str, &opt->value.uint,
 457                                  errp);
 458     default:
 459         abort();
 460     }
 461 }
 462
 463 static bool opts_accepts_any(const QemuOptsList *list)
 464 {
 465     return list->desc[0].name == NULL;
 466 }
 467
 468 int qemu_opt_unset(QemuOpts *opts, const char *name)
 469 {
 470     QemuOpt *opt = qemu_opt_find(opts, name);
 471
 472     assert(opts_accepts_any(opts->list));
 473
 474     if (opt == NULL) {
 475         return -1;
 476     } else {
 477         qemu_opt_del(opt);
 478         return 0;
 479     }
 480 }
 481
 482 static QemuOpt *opt_create(QemuOpts *opts, const char *name, char *value,
 483                            bool prepend)
 484 {
 485     QemuOpt *opt = g_malloc0(sizeof(*opt));
 486
 487     opt->name = g_strdup(name);
 488     opt->str = value;
 489     opt->opts = opts;
 490     if (prepend) {
 491         QTAILQ_INSERT_HEAD(&opts->head, opt, next);
 492     } else {
 493         QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 494     }
 495
 496     return opt;
 497 }
 498
 499 static bool opt_validate(QemuOpt *opt, Error **errp)
 500 {
 501     const QemuOptDesc *desc;
 502     const QemuOptsList *list = opt->opts->list;
 503
 504     desc = find_desc_by_name(list->desc, opt->name);
 505     if (!desc && !opts_accepts_any(list)) {
 506         error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
 507         return false;
 508     }
 509
 510     opt->desc = desc;
 511     if (!qemu_opt_parse(opt, errp)) {
 512         return false;
 513     }
 514
 515     return true;
 516 }
 517
 518 bool qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
 519                   Error **errp)
 520 {
 521     QemuOpt *opt = opt_create(opts, name, g_strdup(value), false);
 522
 523     if (!opt_validate(opt, errp)) {
 524         qemu_opt_del(opt);
 525         return false;
 526     }
 527     return true;
 528 }
 529
 530 bool qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
 531                        Error **errp)
 532 {
 533     QemuOpt *opt;
 534     const QemuOptDesc *desc;
 535     const QemuOptsList *list = opts->list;
 536
 537     desc = find_desc_by_name(list->desc, name);
 538     if (!desc && !opts_accepts_any(list)) {
 539         error_setg(errp, QERR_INVALID_PARAMETER, name);
 540         return false;
 541     }
 542
 543     opt = g_malloc0(sizeof(*opt));
 544     opt->name = g_strdup(name);
 545     opt->opts = opts;
 546     opt->desc = desc;
 547     opt->value.boolean = !!val;
 548     opt->str = g_strdup(val ? "on" : "off");
 549     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 550     return true;
 551 }
 552
 553 bool qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
 554                          Error **errp)
 555 {
 556     QemuOpt *opt;
 557     const QemuOptDesc *desc;
 558     const QemuOptsList *list = opts->list;
 559
 560     desc = find_desc_by_name(list->desc, name);
 561     if (!desc && !opts_accepts_any(list)) {
 562         error_setg(errp, QERR_INVALID_PARAMETER, name);
 563         return false;
 564     }
 565
 566     opt = g_malloc0(sizeof(*opt));
 567     opt->name = g_strdup(name);
 568     opt->opts = opts;
 569     opt->desc = desc;
 570     opt->value.uint = val;
 571     opt->str = g_strdup_printf("%" PRId64, val);
 572     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 573     return true;
 574 }
 575
 576 /**
 577  * For each member of @opts, call @func(@opaque, name, value, @errp).
 578  * @func() may store an Error through @errp, but must return non-zero then.
 579  * When @func() returns non-zero, break the loop and return that value.
 580  * Return zero when the loop completes.
 581  */
 582 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
 583                      Error **errp)
 584 {
 585     QemuOpt *opt;
 586     int rc;
 587
 588     QTAILQ_FOREACH(opt, &opts->head, next) {
 589         rc = func(opaque, opt->name, opt->str, errp);
 590         if (rc) {
 591             return rc;
 592         }
 593         assert(!errp || !*errp);
 594     }
 595     return 0;
 596 }
 597
 598 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
 599 {
 600     QemuOpts *opts;
 601
 602     QTAILQ_FOREACH(opts, &list->head, next) {
 603         if (!opts->id && !id) {
 604             return opts;
 605         }
 606         if (opts->id && id && !strcmp(opts->id, id)) {
 607             return opts;
 608         }
 609     }
 610     return NULL;
 611 }
 612
 613 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
 614                            int fail_if_exists, Error **errp)
 615 {
 616     QemuOpts *opts = NULL;
 617
 618     if (list->merge_lists) {
 619         if (id) {
 620             error_setg(errp, QERR_INVALID_PARAMETER, "id");
 621             return NULL;
 622         }
 623         opts = qemu_opts_find(list, NULL);
 624         if (opts) {
 625             return opts;
 626         }
 627     } else if (id) {
 628         assert(fail_if_exists);
 629         if (!id_wellformed(id)) {
 630             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
 631                        "an identifier");
 632             error_append_hint(errp, "Identifiers consist of letters, digits, "
 633                               "'-', '.', '_', starting with a letter.\n");
 634             return NULL;
 635         }
 636         opts = qemu_opts_find(list, id);
 637         if (opts != NULL) {
 638             error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
 639             return NULL;
 640         }
 641     }
 642     opts = g_malloc0(sizeof(*opts));
 643     opts->id = g_strdup(id);
 644     opts->list = list;
 645     loc_save(&opts->loc);
 646     QTAILQ_INIT(&opts->head);
 647     QTAILQ_INSERT_TAIL(&list->head, opts, next);
 648     return opts;
 649 }
 650
 651 void qemu_opts_reset(QemuOptsList *list)
 652 {
 653     QemuOpts *opts, *next_opts;
 654
 655     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
 656         qemu_opts_del(opts);
 657     }
 658 }
 659
 660 void qemu_opts_loc_restore(QemuOpts *opts)
 661 {
 662     loc_restore(&opts->loc);
 663 }
 664
 665 bool qemu_opts_set(QemuOptsList *list, const char *name, const char *value, Error **errp)
 666 {
 667     QemuOpts *opts;
 668
 669     assert(list->merge_lists);
 670     opts = qemu_opts_create(list, NULL, 0, &error_abort);
 671     return qemu_opt_set(opts, name, value, errp);
 672 }
 673
 674 const char *qemu_opts_id(QemuOpts *opts)
 675 {
 676     return opts->id;
 677 }
 678
 679 /* The id string will be g_free()d by qemu_opts_del */
 680 void qemu_opts_set_id(QemuOpts *opts, char *id)
 681 {
 682     opts->id = id;
 683 }
 684
 685 void qemu_opts_del(QemuOpts *opts)
 686 {
 687     QemuOpt *opt;
 688
 689     if (opts == NULL) {
 690         return;
 691     }
 692
 693     for (;;) {
 694         opt = QTAILQ_FIRST(&opts->head);
 695         if (opt == NULL)
 696             break;
 697         qemu_opt_del(opt);
 698     }
 699     QTAILQ_REMOVE(&opts->list->head, opts, next);
 700     g_free(opts->id);
 701     g_free(opts);
 702 }
 703
 704 /* print value, escaping any commas in value */
 705 static void escaped_print(const char *value)
 706 {
 707     const char *ptr;
 708
 709     for (ptr = value; *ptr; ++ptr) {
 710         if (*ptr == ',') {
 711             putchar(',');
 712         }
 713         putchar(*ptr);
 714     }
 715 }
 716
 717 void qemu_opts_print(QemuOpts *opts, const char *separator)
 718 {
 719     QemuOpt *opt;
 720     QemuOptDesc *desc = opts->list->desc;
 721     const char *sep = "";
 722
 723     if (opts->id) {
 724         printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
 725         sep = separator;
 726     }
 727
 728     if (desc[0].name == NULL) {
 729         QTAILQ_FOREACH(opt, &opts->head, next) {
 730             printf("%s%s=", sep, opt->name);
 731             escaped_print(opt->str);
 732             sep = separator;
 733         }
 734         return;
 735     }
 736     for (; desc && desc->name; desc++) {
 737         const char *value;
 738         opt = qemu_opt_find(opts, desc->name);
 739
 740         value = opt ? opt->str : desc->def_value_str;
 741         if (!value) {
 742             continue;
 743         }
 744         if (desc->type == QEMU_OPT_STRING) {
 745             printf("%s%s=", sep, desc->name);
 746             escaped_print(value);
 747         } else if ((desc->type == QEMU_OPT_SIZE ||
 748                     desc->type == QEMU_OPT_NUMBER) && opt) {
 749             printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
 750         } else {
 751             printf("%s%s=%s", sep, desc->name, value);
 752         }
 753         sep = separator;
 754     }
 755 }
 756
 757 static const char *get_opt_name_value(const char *params,
 758                                       const char *firstname,
 759                                       bool warn_on_flag,
 760                                       bool *help_wanted,
 761                                       char **name, char **value)
 762 {
 763     const char *p;
 764     const char *prefix = "";
 765     size_t len;
 766     bool is_help = false;
 767
 768     len = strcspn(params, "=,");
 769     if (params[len] != '=') {
 770         /* found "foo,more" */
 771         if (firstname) {
 772             /* implicitly named first option */
 773             *name = g_strdup(firstname);
 774             p = get_opt_value(params, value);
 775         } else {
 776             /* option without value, must be a flag */
 777             p = get_opt_name(params, name, len);
 778             if (strncmp(*name, "no", 2) == 0) {
 779                 memmove(*name, *name + 2, strlen(*name + 2) + 1);
 780                 *value = g_strdup("off");
 781                 prefix = "no";
 782             } else {
 783                 *value = g_strdup("on");
 784                 is_help = is_help_option(*name);
 785             }
 786             if (!is_help && warn_on_flag) {
 787                 warn_report("short-form boolean option '%s%s' deprecated", prefix, *name);
 788                 error_printf("Please use %s=%s instead\n", *name, *value);
 789             }
 790         }
 791     } else {
 792         /* found "foo=bar,more" */
 793         p = get_opt_name(params, name, len);
 794         assert(*p == '=');
 795         p++;
 796         p = get_opt_value(p, value);
 797     }
 798
 799     assert(!*p || *p == ',');
 800     if (help_wanted && is_help) {
 801         *help_wanted = true;
 802     }
 803     if (*p == ',') {
 804         p++;
 805     }
 806     return p;
 807 }
 808
 809 static bool opts_do_parse(QemuOpts *opts, const char *params,
 810                           const char *firstname, bool prepend,
 811                           bool warn_on_flag, bool *help_wanted, Error **errp)
 812 {
 813     char *option, *value;
 814     const char *p;
 815     QemuOpt *opt;
 816
 817     for (p = params; *p;) {
 818         p = get_opt_name_value(p, firstname, warn_on_flag, help_wanted, &option, &value);
 819         if (help_wanted && *help_wanted) {
 820             g_free(option);
 821             g_free(value);
 822             return false;
 823         }
 824         firstname = NULL;
 825
 826         if (!strcmp(option, "id")) {
 827             g_free(option);
 828             g_free(value);
 829             continue;
 830         }
 831
 832         opt = opt_create(opts, option, value, prepend);
 833         g_free(option);
 834         if (!opt_validate(opt, errp)) {
 835             qemu_opt_del(opt);
 836             return false;
 837         }
 838     }
 839
 840     return true;
 841 }
 842
 843 static char *opts_parse_id(const char *params)
 844 {
 845     const char *p;
 846     char *name, *value;
 847
 848     for (p = params; *p;) {
 849         p = get_opt_name_value(p, NULL, false, NULL, &name, &value);
 850         if (!strcmp(name, "id")) {
 851             g_free(name);
 852             return value;
 853         }
 854         g_free(name);
 855         g_free(value);
 856     }
 857
 858     return NULL;
 859 }
 860
 861 bool has_help_option(const char *params)
 862 {
 863     const char *p;
 864     char *name, *value;
 865     bool ret = false;
 866
 867     for (p = params; *p;) {
 868         p = get_opt_name_value(p, NULL, false, &ret, &name, &value);
 869         g_free(name);
 870         g_free(value);
 871         if (ret) {
 872             return true;
 873         }
 874     }
 875
 876     return false;
 877 }
 878
 879 /**
 880  * Store options parsed from @params into @opts.
 881  * If @firstname is non-null, the first key=value in @params may omit
 882  * key=, and is treated as if key was @firstname.
 883  * On error, store an error object through @errp if non-null.
 884  */
 885 bool qemu_opts_do_parse(QemuOpts *opts, const char *params,
 886                        const char *firstname, Error **errp)
 887 {
 888     return opts_do_parse(opts, params, firstname, false, false, NULL, errp);
 889 }
 890
 891 static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
 892                             bool permit_abbrev, bool defaults,
 893                             bool warn_on_flag, bool *help_wanted, Error **errp)
 894 {
 895     const char *firstname;
 896     char *id = opts_parse_id(params);
 897     QemuOpts *opts;
 898
 899     assert(!permit_abbrev || list->implied_opt_name);
 900     firstname = permit_abbrev ? list->implied_opt_name : NULL;
 901
 902     /*
 903      * This code doesn't work for defaults && !list->merge_lists: when
 904      * params has no id=, and list has an element with !opts->id, it
 905      * appends a new element instead of returning the existing opts.
 906      * However, we got no use for this case.  Guard against possible
 907      * (if unlikely) future misuse:
 908      */
 909     assert(!defaults || list->merge_lists);
 910     opts = qemu_opts_create(list, id, !list->merge_lists, errp);
 911     g_free(id);
 912     if (opts == NULL) {
 913         return NULL;
 914     }
 915
 916     if (!opts_do_parse(opts, params, firstname, defaults,
 917                        warn_on_flag, help_wanted, errp)) {
 918         qemu_opts_del(opts);
 919         return NULL;
 920     }
 921
 922     return opts;
 923 }
 924
 925 /**
 926  * Create a QemuOpts in @list and with options parsed from @params.
 927  * If @permit_abbrev, the first key=value in @params may omit key=,
 928  * and is treated as if key was @list->implied_opt_name.
 929  * On error, store an error object through @errp if non-null.
 930  * Return the new QemuOpts on success, null pointer on error.
 931  */
 932 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
 933                           bool permit_abbrev, Error **errp)
 934 {
 935     return opts_parse(list, params, permit_abbrev, false, false, NULL, errp);
 936 }
 937
 938 /**
 939  * Create a QemuOpts in @list and with options parsed from @params.
 940  * If @permit_abbrev, the first key=value in @params may omit key=,
 941  * and is treated as if key was @list->implied_opt_name.
 942  * Report errors with error_report_err().  This is inappropriate in
 943  * QMP context.  Do not use this function there!
 944  * Return the new QemuOpts on success, null pointer on error.
 945  */
 946 QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
 947                                   bool permit_abbrev)
 948 {
 949     Error *err = NULL;
 950     QemuOpts *opts;
 951     bool help_wanted = false;
 952
 953     opts = opts_parse(list, params, permit_abbrev, false, true,
 954                       opts_accepts_any(list) ? NULL : &help_wanted,
 955                       &err);
 956     if (!opts) {
 957         assert(!!err + !!help_wanted == 1);
 958         if (help_wanted) {
 959             qemu_opts_print_help(list, true);
 960         } else {
 961             error_report_err(err);
 962         }
 963     }
 964     return opts;
 965 }
 966
 967 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,
 968                             int permit_abbrev)
 969 {
 970     QemuOpts *opts;
 971
 972     opts = opts_parse(list, params, permit_abbrev, true, false, NULL, NULL);
 973     assert(opts);
 974 }
 975
 976 static bool qemu_opts_from_qdict_entry(QemuOpts *opts,
 977                                        const QDictEntry *entry,
 978                                        Error **errp)
 979 {
 980     const char *key = qdict_entry_key(entry);
 981     QObject *obj = qdict_entry_value(entry);
 982     char buf[32];
 983     g_autofree char *tmp = NULL;
 984     const char *value;
 985
 986     if (!strcmp(key, "id")) {
 987         return true;
 988     }
 989
 990     switch (qobject_type(obj)) {
 991     case QTYPE_QSTRING:
 992         value = qstring_get_str(qobject_to(QString, obj));
 993         break;
 994     case QTYPE_QNUM:
 995         tmp = qnum_to_string(qobject_to(QNum, obj));
 996         value = tmp;
 997         break;
 998     case QTYPE_QBOOL:
 999         pstrcpy(buf, sizeof(buf),
1000                 qbool_get_bool(qobject_to(QBool, obj)) ? "on" : "off");
1001         value = buf;
1002         break;
1003     default:
1004         return true;
1005     }
1006
1007     return qemu_opt_set(opts, key, value, errp);
1008 }
1009
1010 /*
1011  * Create QemuOpts from a QDict.
1012  * Use value of key "id" as ID if it exists and is a QString.  Only
1013  * QStrings, QNums and QBools are copied.  Entries with other types
1014  * are silently ignored.
1015  */
1016 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
1017                                Error **errp)
1018 {
1019     QemuOpts *opts;
1020     const QDictEntry *entry;
1021
1022     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1, errp);
1023     if (!opts) {
1024         return NULL;
1025     }
1026
1027     assert(opts != NULL);
1028
1029     for (entry = qdict_first(qdict);
1030          entry;
1031          entry = qdict_next(qdict, entry)) {
1032         if (!qemu_opts_from_qdict_entry(opts, entry, errp)) {
1033             qemu_opts_del(opts);
1034             return NULL;
1035         }
1036     }
1037
1038     return opts;
1039 }
1040
1041 /*
1042  * Adds all QDict entries to the QemuOpts that can be added and removes them
1043  * from the QDict. When this function returns, the QDict contains only those
1044  * entries that couldn't be added to the QemuOpts.
1045  */
1046 bool qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
1047 {
1048     const QDictEntry *entry, *next;
1049
1050     entry = qdict_first(qdict);
1051
1052     while (entry != NULL) {
1053         next = qdict_next(qdict, entry);
1054
1055         if (find_desc_by_name(opts->list->desc, entry->key)) {
1056             if (!qemu_opts_from_qdict_entry(opts, entry, errp)) {
1057                 return false;
1058             }
1059             qdict_del(qdict, entry->key);
1060         }
1061
1062         entry = next;
1063     }
1064
1065     return true;
1066 }
1067
1068 /*
1069  * Convert from QemuOpts to QDict. The QDict values are of type QString.
1070  *
1071  * If @list is given, only add those options to the QDict that are contained in
1072  * the list. If @del is true, any options added to the QDict are removed from
1073  * the QemuOpts, otherwise they remain there.
1074  *
1075  * If two options in @opts have the same name, they are processed in order
1076  * so that the last one wins (consistent with the reverse iteration in
1077  * qemu_opt_find()), but all of them are deleted if @del is true.
1078  *
1079  * TODO We'll want to use types appropriate for opt->desc->type, but
1080  * this is enough for now.
1081  */
1082 QDict *qemu_opts_to_qdict_filtered(QemuOpts *opts, QDict *qdict,
1083                                    QemuOptsList *list, bool del)
1084 {
1085     QemuOpt *opt, *next;
1086
1087     if (!qdict) {
1088         qdict = qdict_new();
1089     }
1090     if (opts->id) {
1091         qdict_put_str(qdict, "id", opts->id);
1092     }
1093     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next) {
1094         if (list) {
1095             QemuOptDesc *desc;
1096             bool found = false;
1097             for (desc = list->desc; desc->name; desc++) {
1098                 if (!strcmp(desc->name, opt->name)) {
1099                     found = true;
1100                     break;
1101                 }
1102             }
1103             if (!found) {
1104                 continue;
1105             }
1106         }
1107         qdict_put_str(qdict, opt->name, opt->str);
1108         if (del) {
1109             qemu_opt_del(opt);
1110         }
1111     }
1112     return qdict;
1113 }
1114
1115 /* Copy all options in a QemuOpts to the given QDict. See
1116  * qemu_opts_to_qdict_filtered() for details. */
1117 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
1118 {
1119     return qemu_opts_to_qdict_filtered(opts, qdict, NULL, false);
1120 }
1121
1122 /* Validate parsed opts against descriptions where no
1123  * descriptions were provided in the QemuOptsList.
1124  */
1125 bool qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
1126 {
1127     QemuOpt *opt;
1128
1129     assert(opts_accepts_any(opts->list));
1130
1131     QTAILQ_FOREACH(opt, &opts->head, next) {
1132         opt->desc = find_desc_by_name(desc, opt->name);
1133         if (!opt->desc) {
1134             error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
1135             return false;
1136         }
1137
1138         if (!qemu_opt_parse(opt, errp)) {
1139             return false;
1140         }
1141     }
1142
1143     return true;
1144 }
1145
1146 /**
1147  * For each member of @list, call @func(@opaque, member, @errp).
1148  * Call it with the current location temporarily set to the member's.
1149  * @func() may store an Error through @errp, but must return non-zero then.
1150  * When @func() returns non-zero, break the loop and return that value.
1151  * Return zero when the loop completes.
1152  */
1153 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
1154                       void *opaque, Error **errp)
1155 {
1156     Location loc;
1157     QemuOpts *opts;
1158     int rc = 0;
1159
1160     loc_push_none(&loc);
1161     QTAILQ_FOREACH(opts, &list->head, next) {
1162         loc_restore(&opts->loc);
1163         rc = func(opaque, opts, errp);
1164         if (rc) {
1165             break;
1166         }
1167         assert(!errp || !*errp);
1168     }
1169     loc_pop(&loc);
1170     return rc;
1171 }
1172
1173 static size_t count_opts_list(QemuOptsList *list)
1174 {
1175     QemuOptDesc *desc = NULL;
1176     size_t num_opts = 0;
1177
1178     if (!list) {
1179         return 0;
1180     }
1181
1182     desc = list->desc;
1183     while (desc && desc->name) {
1184         num_opts++;
1185         desc++;
1186     }
1187
1188     return num_opts;
1189 }
1190
1191 void qemu_opts_free(QemuOptsList *list)
1192 {
1193     g_free(list);
1194 }
1195
1196 /* Realloc dst option list and append options from an option list (list)
1197  * to it. dst could be NULL or a malloced list.
1198  * The lifetime of dst must be shorter than the input list because the
1199  * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
1200  */
1201 QemuOptsList *qemu_opts_append(QemuOptsList *dst,
1202                                QemuOptsList *list)
1203 {
1204     size_t num_opts, num_dst_opts;
1205     QemuOptDesc *desc;
1206     bool need_init = false;
1207     bool need_head_update;
1208
1209     if (!list) {
1210         return dst;
1211     }
1212
1213     /* If dst is NULL, after realloc, some area of dst should be initialized
1214      * before adding options to it.
1215      */
1216     if (!dst) {
1217         need_init = true;
1218         need_head_update = true;
1219     } else {
1220         /* Moreover, even if dst is not NULL, the realloc may move it to a
1221          * different address in which case we may get a stale tail pointer
1222          * in dst->head. */
1223         need_head_update = QTAILQ_EMPTY(&dst->head);
1224     }
1225
1226     num_opts = count_opts_list(dst);
1227     num_dst_opts = num_opts;
1228     num_opts += count_opts_list(list);
1229     dst = g_realloc(dst, sizeof(QemuOptsList) +
1230                     (num_opts + 1) * sizeof(QemuOptDesc));
1231     if (need_init) {
1232         dst->name = NULL;
1233         dst->implied_opt_name = NULL;
1234         dst->merge_lists = false;
1235     }
1236     if (need_head_update) {
1237         QTAILQ_INIT(&dst->head);
1238     }
1239     dst->desc[num_dst_opts].name = NULL;
1240
1241     /* append list->desc to dst->desc */
1242     if (list) {
1243         desc = list->desc;
1244         while (desc && desc->name) {
1245             if (find_desc_by_name(dst->desc, desc->name) == NULL) {
1246                 dst->desc[num_dst_opts++] = *desc;
1247                 dst->desc[num_dst_opts].name = NULL;
1248             }
1249             desc++;
1250         }
1251     }
1252
1253     return dst;
1254 }