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-common.h"
  30 #include "qemu/error-report.h"
  31 #include "qapi/qmp/qbool.h"
  32 #include "qapi/qmp/qdict.h"
  33 #include "qapi/qmp/qnum.h"
  34 #include "qapi/qmp/qstring.h"
  35 #include "qapi/qmp/qerror.h"
  36 #include "qemu/option_int.h"
  37 #include "qemu/cutils.h"
  38 #include "qemu/id.h"
  39 #include "qemu/help_option.h"
  40
  41 /*
  42  * Extracts the name of an option from the parameter string (p points at the
  43  * first byte of the option name)
  44  *
  45  * The option name is delimited by delim (usually , or =) or the string end
  46  * and is copied into option. The caller is responsible for free'ing option
  47  * when no longer required.
  48  *
  49  * The return value is the position of the delimiter/zero byte after the option
  50  * name in p.
  51  */
  52 static const char *get_opt_name(const char *p, char **option, char delim)
  53 {
  54     char *offset = strchr(p, delim);
  55
  56     if (offset) {
  57         *option = g_strndup(p, offset - p);
  58         return offset;
  59     } else {
  60         *option = g_strdup(p);
  61         return p + strlen(p);
  62     }
  63 }
  64
  65 /*
  66  * Extracts the value of an option from the parameter string p (p points at the
  67  * first byte of the option value)
  68  *
  69  * This function is comparable to get_opt_name with the difference that the
  70  * delimiter is fixed to be comma which starts a new option. To specify an
  71  * option value that contains commas, double each comma.
  72  */
  73 const char *get_opt_value(const char *p, char **value)
  74 {
  75     size_t capacity = 0, length;
  76     const char *offset;
  77
  78     *value = NULL;
  79     while (1) {
  80         offset = qemu_strchrnul(p, ',');
  81         length = offset - p;
  82         if (*offset != '\0' && *(offset + 1) == ',') {
  83             length++;
  84         }
  85         *value = g_renew(char, *value, capacity + length + 1);
  86         strncpy(*value + capacity, p, length);
  87         (*value)[capacity + length] = '\0';
  88         capacity += length;
  89         if (*offset == '\0' ||
  90             *(offset + 1) != ',') {
  91             break;
  92         }
  93
  94         p += (offset - p) + 2;
  95     }
  96
  97     return offset;
  98 }
  99
 100 static void parse_option_bool(const char *name, const char *value, bool *ret,
 101                               Error **errp)
 102 {
 103     if (!strcmp(value, "on")) {
 104         *ret = 1;
 105     } else if (!strcmp(value, "off")) {
 106         *ret = 0;
 107     } else {
 108         error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
 109                    name, "'on' or 'off'");
 110     }
 111 }
 112
 113 static void parse_option_number(const char *name, const char *value,
 114                                 uint64_t *ret, Error **errp)
 115 {
 116     uint64_t number;
 117     int err;
 118
 119     err = qemu_strtou64(value, NULL, 0, &number);
 120     if (err == -ERANGE) {
 121         error_setg(errp, "Value '%s' is too large for parameter '%s'",
 122                    value, name);
 123         return;
 124     }
 125     if (err) {
 126         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
 127         return;
 128     }
 129     *ret = number;
 130 }
 131
 132 static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
 133                                             const char *name)
 134 {
 135     int i;
 136
 137     for (i = 0; desc[i].name != NULL; i++) {
 138         if (strcmp(desc[i].name, name) == 0) {
 139             return &desc[i];
 140         }
 141     }
 142
 143     return NULL;
 144 }
 145
 146 void parse_option_size(const char *name, const char *value,
 147                        uint64_t *ret, Error **errp)
 148 {
 149     uint64_t size;
 150     int err;
 151
 152     err = qemu_strtosz(value, NULL, &size);
 153     if (err == -ERANGE) {
 154         error_setg(errp, "Value '%s' is out of range for parameter '%s'",
 155                    value, name);
 156         return;
 157     }
 158     if (err) {
 159         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
 160                    "a non-negative number below 2^64");
 161         error_append_hint(errp, "Optional suffix k, M, G, T, P or E means"
 162                           " kilo-, mega-, giga-, tera-, peta-\n"
 163                           "and exabytes, respectively.\n");
 164         return;
 165     }
 166     *ret = size;
 167 }
 168
 169 bool has_help_option(const char *param)
 170 {
 171     const char *p = param;
 172     bool result = false;
 173
 174     while (*p && !result) {
 175         char *value;
 176
 177         p = get_opt_value(p, &value);
 178         if (*p) {
 179             p++;
 180         }
 181
 182         result = is_help_option(value);
 183         g_free(value);
 184     }
 185
 186     return result;
 187 }
 188
 189 bool is_valid_option_list(const char *p)
 190 {
 191     char *value = NULL;
 192     bool result = false;
 193
 194     while (*p) {
 195         p = get_opt_value(p, &value);
 196         if ((*p && !*++p) ||
 197             (!*value || *value == ',')) {
 198             goto out;
 199         }
 200
 201         g_free(value);
 202         value = NULL;
 203     }
 204
 205     result = true;
 206 out:
 207     g_free(value);
 208     return result;
 209 }
 210
 211 void qemu_opts_print_help(QemuOptsList *list)
 212 {
 213     QemuOptDesc *desc;
 214
 215     assert(list);
 216     desc = list->desc;
 217     while (desc && desc->name) {
 218         printf("%-16s %s\n", desc->name,
 219                desc->help ? desc->help : "No description available");
 220         desc++;
 221     }
 222 }
 223 /* ------------------------------------------------------------------ */
 224
 225 QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
 226 {
 227     QemuOpt *opt;
 228
 229     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
 230         if (strcmp(opt->name, name) != 0)
 231             continue;
 232         return opt;
 233     }
 234     return NULL;
 235 }
 236
 237 static void qemu_opt_del(QemuOpt *opt)
 238 {
 239     QTAILQ_REMOVE(&opt->opts->head, opt, next);
 240     g_free(opt->name);
 241     g_free(opt->str);
 242     g_free(opt);
 243 }
 244
 245 /* qemu_opt_set allows many settings for the same option.
 246  * This function deletes all settings for an option.
 247  */
 248 static void qemu_opt_del_all(QemuOpts *opts, const char *name)
 249 {
 250     QemuOpt *opt, *next_opt;
 251
 252     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next_opt) {
 253         if (!strcmp(opt->name, name)) {
 254             qemu_opt_del(opt);
 255         }
 256     }
 257 }
 258
 259 const char *qemu_opt_get(QemuOpts *opts, const char *name)
 260 {
 261     QemuOpt *opt;
 262
 263     if (opts == NULL) {
 264         return NULL;
 265     }
 266
 267     opt = qemu_opt_find(opts, name);
 268     if (!opt) {
 269         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
 270         if (desc && desc->def_value_str) {
 271             return desc->def_value_str;
 272         }
 273     }
 274     return opt ? opt->str : NULL;
 275 }
 276
 277 void qemu_opt_iter_init(QemuOptsIter *iter, QemuOpts *opts, const char *name)
 278 {
 279     iter->opts = opts;
 280     iter->opt = QTAILQ_FIRST(&opts->head);
 281     iter->name = name;
 282 }
 283
 284 const char *qemu_opt_iter_next(QemuOptsIter *iter)
 285 {
 286     QemuOpt *ret = iter->opt;
 287     if (iter->name) {
 288         while (ret && !g_str_equal(iter->name, ret->name)) {
 289             ret = QTAILQ_NEXT(ret, next);
 290         }
 291     }
 292     iter->opt = ret ? QTAILQ_NEXT(ret, next) : NULL;
 293     return ret ? ret->str : NULL;
 294 }
 295
 296 /* Get a known option (or its default) and remove it from the list
 297  * all in one action. Return a malloced string of the option value.
 298  * Result must be freed by caller with g_free().
 299  */
 300 char *qemu_opt_get_del(QemuOpts *opts, const char *name)
 301 {
 302     QemuOpt *opt;
 303     const QemuOptDesc *desc;
 304     char *str = NULL;
 305
 306     if (opts == NULL) {
 307         return NULL;
 308     }
 309
 310     opt = qemu_opt_find(opts, name);
 311     if (!opt) {
 312         desc = find_desc_by_name(opts->list->desc, name);
 313         if (desc && desc->def_value_str) {
 314             str = g_strdup(desc->def_value_str);
 315         }
 316         return str;
 317     }
 318     str = opt->str;
 319     opt->str = NULL;
 320     qemu_opt_del_all(opts, name);
 321     return str;
 322 }
 323
 324 bool qemu_opt_has_help_opt(QemuOpts *opts)
 325 {
 326     QemuOpt *opt;
 327
 328     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
 329         if (is_help_option(opt->name)) {
 330             return true;
 331         }
 332     }
 333     return false;
 334 }
 335
 336 static bool qemu_opt_get_bool_helper(QemuOpts *opts, const char *name,
 337                                      bool defval, bool del)
 338 {
 339     QemuOpt *opt;
 340     bool ret = defval;
 341
 342     if (opts == NULL) {
 343         return ret;
 344     }
 345
 346     opt = qemu_opt_find(opts, name);
 347     if (opt == NULL) {
 348         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
 349         if (desc && desc->def_value_str) {
 350             parse_option_bool(name, desc->def_value_str, &ret, &error_abort);
 351         }
 352         return ret;
 353     }
 354     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
 355     ret = opt->value.boolean;
 356     if (del) {
 357         qemu_opt_del_all(opts, name);
 358     }
 359     return ret;
 360 }
 361
 362 bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
 363 {
 364     return qemu_opt_get_bool_helper(opts, name, defval, false);
 365 }
 366
 367 bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
 368 {
 369     return qemu_opt_get_bool_helper(opts, name, defval, true);
 370 }
 371
 372 static uint64_t qemu_opt_get_number_helper(QemuOpts *opts, const char *name,
 373                                            uint64_t defval, bool del)
 374 {
 375     QemuOpt *opt;
 376     uint64_t ret = defval;
 377
 378     if (opts == NULL) {
 379         return ret;
 380     }
 381
 382     opt = qemu_opt_find(opts, name);
 383     if (opt == NULL) {
 384         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
 385         if (desc && desc->def_value_str) {
 386             parse_option_number(name, desc->def_value_str, &ret, &error_abort);
 387         }
 388         return ret;
 389     }
 390     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
 391     ret = opt->value.uint;
 392     if (del) {
 393         qemu_opt_del_all(opts, name);
 394     }
 395     return ret;
 396 }
 397
 398 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
 399 {
 400     return qemu_opt_get_number_helper(opts, name, defval, false);
 401 }
 402
 403 uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
 404                                  uint64_t defval)
 405 {
 406     return qemu_opt_get_number_helper(opts, name, defval, true);
 407 }
 408
 409 static uint64_t qemu_opt_get_size_helper(QemuOpts *opts, const char *name,
 410                                          uint64_t defval, bool del)
 411 {
 412     QemuOpt *opt;
 413     uint64_t ret = defval;
 414
 415     if (opts == NULL) {
 416         return ret;
 417     }
 418
 419     opt = qemu_opt_find(opts, name);
 420     if (opt == NULL) {
 421         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
 422         if (desc && desc->def_value_str) {
 423             parse_option_size(name, desc->def_value_str, &ret, &error_abort);
 424         }
 425         return ret;
 426     }
 427     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
 428     ret = opt->value.uint;
 429     if (del) {
 430         qemu_opt_del_all(opts, name);
 431     }
 432     return ret;
 433 }
 434
 435 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
 436 {
 437     return qemu_opt_get_size_helper(opts, name, defval, false);
 438 }
 439
 440 uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
 441                                uint64_t defval)
 442 {
 443     return qemu_opt_get_size_helper(opts, name, defval, true);
 444 }
 445
 446 static void qemu_opt_parse(QemuOpt *opt, Error **errp)
 447 {
 448     if (opt->desc == NULL)
 449         return;
 450
 451     switch (opt->desc->type) {
 452     case QEMU_OPT_STRING:
 453         /* nothing */
 454         return;
 455     case QEMU_OPT_BOOL:
 456         parse_option_bool(opt->name, opt->str, &opt->value.boolean, errp);
 457         break;
 458     case QEMU_OPT_NUMBER:
 459         parse_option_number(opt->name, opt->str, &opt->value.uint, errp);
 460         break;
 461     case QEMU_OPT_SIZE:
 462         parse_option_size(opt->name, opt->str, &opt->value.uint, errp);
 463         break;
 464     default:
 465         abort();
 466     }
 467 }
 468
 469 static bool opts_accepts_any(const QemuOpts *opts)
 470 {
 471     return opts->list->desc[0].name == NULL;
 472 }
 473
 474 int qemu_opt_unset(QemuOpts *opts, const char *name)
 475 {
 476     QemuOpt *opt = qemu_opt_find(opts, name);
 477
 478     assert(opts_accepts_any(opts));
 479
 480     if (opt == NULL) {
 481         return -1;
 482     } else {
 483         qemu_opt_del(opt);
 484         return 0;
 485     }
 486 }
 487
 488 static void opt_set(QemuOpts *opts, const char *name, char *value,
 489                     bool prepend, Error **errp)
 490 {
 491     QemuOpt *opt;
 492     const QemuOptDesc *desc;
 493     Error *local_err = NULL;
 494
 495     desc = find_desc_by_name(opts->list->desc, name);
 496     if (!desc && !opts_accepts_any(opts)) {
 497         g_free(value);
 498         error_setg(errp, QERR_INVALID_PARAMETER, name);
 499         return;
 500     }
 501
 502     opt = g_malloc0(sizeof(*opt));
 503     opt->name = g_strdup(name);
 504     opt->opts = opts;
 505     if (prepend) {
 506         QTAILQ_INSERT_HEAD(&opts->head, opt, next);
 507     } else {
 508         QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 509     }
 510     opt->desc = desc;
 511     opt->str = value;
 512     qemu_opt_parse(opt, &local_err);
 513     if (local_err) {
 514         error_propagate(errp, local_err);
 515         qemu_opt_del(opt);
 516     }
 517 }
 518
 519 void qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
 520                   Error **errp)
 521 {
 522     opt_set(opts, name, g_strdup(value), false, errp);
 523 }
 524
 525 void qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
 526                        Error **errp)
 527 {
 528     QemuOpt *opt;
 529     const QemuOptDesc *desc = opts->list->desc;
 530
 531     opt = g_malloc0(sizeof(*opt));
 532     opt->desc = find_desc_by_name(desc, name);
 533     if (!opt->desc && !opts_accepts_any(opts)) {
 534         error_setg(errp, QERR_INVALID_PARAMETER, name);
 535         g_free(opt);
 536         return;
 537     }
 538
 539     opt->name = g_strdup(name);
 540     opt->opts = opts;
 541     opt->value.boolean = !!val;
 542     opt->str = g_strdup(val ? "on" : "off");
 543     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 544 }
 545
 546 void qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
 547                          Error **errp)
 548 {
 549     QemuOpt *opt;
 550     const QemuOptDesc *desc = opts->list->desc;
 551
 552     opt = g_malloc0(sizeof(*opt));
 553     opt->desc = find_desc_by_name(desc, name);
 554     if (!opt->desc && !opts_accepts_any(opts)) {
 555         error_setg(errp, QERR_INVALID_PARAMETER, name);
 556         g_free(opt);
 557         return;
 558     }
 559
 560     opt->name = g_strdup(name);
 561     opt->opts = opts;
 562     opt->value.uint = val;
 563     opt->str = g_strdup_printf("%" PRId64, val);
 564     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 565 }
 566
 567 /**
 568  * For each member of @opts, call @func(@opaque, name, value, @errp).
 569  * @func() may store an Error through @errp, but must return non-zero then.
 570  * When @func() returns non-zero, break the loop and return that value.
 571  * Return zero when the loop completes.
 572  */
 573 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
 574                      Error **errp)
 575 {
 576     QemuOpt *opt;
 577     int rc;
 578
 579     QTAILQ_FOREACH(opt, &opts->head, next) {
 580         rc = func(opaque, opt->name, opt->str, errp);
 581         if (rc) {
 582             return rc;
 583         }
 584         assert(!errp || !*errp);
 585     }
 586     return 0;
 587 }
 588
 589 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
 590 {
 591     QemuOpts *opts;
 592
 593     QTAILQ_FOREACH(opts, &list->head, next) {
 594         if (!opts->id && !id) {
 595             return opts;
 596         }
 597         if (opts->id && id && !strcmp(opts->id, id)) {
 598             return opts;
 599         }
 600     }
 601     return NULL;
 602 }
 603
 604 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
 605                            int fail_if_exists, Error **errp)
 606 {
 607     QemuOpts *opts = NULL;
 608
 609     if (id) {
 610         if (!id_wellformed(id)) {
 611             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
 612                        "an identifier");
 613             error_append_hint(errp, "Identifiers consist of letters, digits, "
 614                               "'-', '.', '_', starting with a letter.\n");
 615             return NULL;
 616         }
 617         opts = qemu_opts_find(list, id);
 618         if (opts != NULL) {
 619             if (fail_if_exists && !list->merge_lists) {
 620                 error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
 621                 return NULL;
 622             } else {
 623                 return opts;
 624             }
 625         }
 626     } else if (list->merge_lists) {
 627         opts = qemu_opts_find(list, NULL);
 628         if (opts) {
 629             return opts;
 630         }
 631     }
 632     opts = g_malloc0(sizeof(*opts));
 633     opts->id = g_strdup(id);
 634     opts->list = list;
 635     loc_save(&opts->loc);
 636     QTAILQ_INIT(&opts->head);
 637     QTAILQ_INSERT_TAIL(&list->head, opts, next);
 638     return opts;
 639 }
 640
 641 void qemu_opts_reset(QemuOptsList *list)
 642 {
 643     QemuOpts *opts, *next_opts;
 644
 645     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
 646         qemu_opts_del(opts);
 647     }
 648 }
 649
 650 void qemu_opts_loc_restore(QemuOpts *opts)
 651 {
 652     loc_restore(&opts->loc);
 653 }
 654
 655 void qemu_opts_set(QemuOptsList *list, const char *id,
 656                    const char *name, const char *value, Error **errp)
 657 {
 658     QemuOpts *opts;
 659     Error *local_err = NULL;
 660
 661     opts = qemu_opts_create(list, id, 1, &local_err);
 662     if (local_err) {
 663         error_propagate(errp, local_err);
 664         return;
 665     }
 666     qemu_opt_set(opts, name, value, errp);
 667 }
 668
 669 const char *qemu_opts_id(QemuOpts *opts)
 670 {
 671     return opts->id;
 672 }
 673
 674 /* The id string will be g_free()d by qemu_opts_del */
 675 void qemu_opts_set_id(QemuOpts *opts, char *id)
 676 {
 677     opts->id = id;
 678 }
 679
 680 void qemu_opts_del(QemuOpts *opts)
 681 {
 682     QemuOpt *opt;
 683
 684     if (opts == NULL) {
 685         return;
 686     }
 687
 688     for (;;) {
 689         opt = QTAILQ_FIRST(&opts->head);
 690         if (opt == NULL)
 691             break;
 692         qemu_opt_del(opt);
 693     }
 694     QTAILQ_REMOVE(&opts->list->head, opts, next);
 695     g_free(opts->id);
 696     g_free(opts);
 697 }
 698
 699 /* print value, escaping any commas in value */
 700 static void escaped_print(const char *value)
 701 {
 702     const char *ptr;
 703
 704     for (ptr = value; *ptr; ++ptr) {
 705         if (*ptr == ',') {
 706             putchar(',');
 707         }
 708         putchar(*ptr);
 709     }
 710 }
 711
 712 void qemu_opts_print(QemuOpts *opts, const char *separator)
 713 {
 714     QemuOpt *opt;
 715     QemuOptDesc *desc = opts->list->desc;
 716     const char *sep = "";
 717
 718     if (opts->id) {
 719         printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
 720         sep = separator;
 721     }
 722
 723     if (desc[0].name == NULL) {
 724         QTAILQ_FOREACH(opt, &opts->head, next) {
 725             printf("%s%s=", sep, opt->name);
 726             escaped_print(opt->str);
 727             sep = separator;
 728         }
 729         return;
 730     }
 731     for (; desc && desc->name; desc++) {
 732         const char *value;
 733         opt = qemu_opt_find(opts, desc->name);
 734
 735         value = opt ? opt->str : desc->def_value_str;
 736         if (!value) {
 737             continue;
 738         }
 739         if (desc->type == QEMU_OPT_STRING) {
 740             printf("%s%s=", sep, desc->name);
 741             escaped_print(value);
 742         } else if ((desc->type == QEMU_OPT_SIZE ||
 743                     desc->type == QEMU_OPT_NUMBER) && opt) {
 744             printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
 745         } else {
 746             printf("%s%s=%s", sep, desc->name, value);
 747         }
 748         sep = separator;
 749     }
 750 }
 751
 752 static void opts_do_parse(QemuOpts *opts, const char *params,
 753                           const char *firstname, bool prepend, Error **errp)
 754 {
 755     char *option = NULL;
 756     char *value = NULL;
 757     const char *p,*pe,*pc;
 758     Error *local_err = NULL;
 759
 760     for (p = params; *p != '\0'; p++) {
 761         pe = strchr(p, '=');
 762         pc = strchr(p, ',');
 763         if (!pe || (pc && pc < pe)) {
 764             /* found "foo,more" */
 765             if (p == params && firstname) {
 766                 /* implicitly named first option */
 767                 option = g_strdup(firstname);
 768                 p = get_opt_value(p, &value);
 769             } else {
 770                 /* option without value, probably a flag */
 771                 p = get_opt_name(p, &option, ',');
 772                 if (strncmp(option, "no", 2) == 0) {
 773                     memmove(option, option+2, strlen(option+2)+1);
 774                     value = g_strdup("off");
 775                 } else {
 776                     value = g_strdup("on");
 777                 }
 778             }
 779         } else {
 780             /* found "foo=bar,more" */
 781             p = get_opt_name(p, &option, '=');
 782             assert(*p == '=');
 783             p++;
 784             p = get_opt_value(p, &value);
 785         }
 786         if (strcmp(option, "id") != 0) {
 787             /* store and parse */
 788             opt_set(opts, option, value, prepend, &local_err);
 789             value = NULL;
 790             if (local_err) {
 791                 error_propagate(errp, local_err);
 792                 goto cleanup;
 793             }
 794         }
 795         if (*p != ',') {
 796             break;
 797         }
 798         g_free(option);
 799         g_free(value);
 800         option = value = NULL;
 801     }
 802
 803  cleanup:
 804     g_free(option);
 805     g_free(value);
 806 }
 807
 808 /**
 809  * Store options parsed from @params into @opts.
 810  * If @firstname is non-null, the first key=value in @params may omit
 811  * key=, and is treated as if key was @firstname.
 812  * On error, store an error object through @errp if non-null.
 813  */
 814 void qemu_opts_do_parse(QemuOpts *opts, const char *params,
 815                        const char *firstname, Error **errp)
 816 {
 817     opts_do_parse(opts, params, firstname, false, errp);
 818 }
 819
 820 static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
 821                             bool permit_abbrev, bool defaults, Error **errp)
 822 {
 823     const char *firstname;
 824     char *id = NULL;
 825     const char *p;
 826     QemuOpts *opts;
 827     Error *local_err = NULL;
 828
 829     assert(!permit_abbrev || list->implied_opt_name);
 830     firstname = permit_abbrev ? list->implied_opt_name : NULL;
 831
 832     if (strncmp(params, "id=", 3) == 0) {
 833         get_opt_value(params + 3, &id);
 834     } else if ((p = strstr(params, ",id=")) != NULL) {
 835         get_opt_value(p + 4, &id);
 836     }
 837
 838     /*
 839      * This code doesn't work for defaults && !list->merge_lists: when
 840      * params has no id=, and list has an element with !opts->id, it
 841      * appends a new element instead of returning the existing opts.
 842      * However, we got no use for this case.  Guard against possible
 843      * (if unlikely) future misuse:
 844      */
 845     assert(!defaults || list->merge_lists);
 846     opts = qemu_opts_create(list, id, !defaults, &local_err);
 847     g_free(id);
 848     if (opts == NULL) {
 849         error_propagate(errp, local_err);
 850         return NULL;
 851     }
 852
 853     opts_do_parse(opts, params, firstname, defaults, &local_err);
 854     if (local_err) {
 855         error_propagate(errp, local_err);
 856         qemu_opts_del(opts);
 857         return NULL;
 858     }
 859
 860     return opts;
 861 }
 862
 863 /**
 864  * Create a QemuOpts in @list and with options parsed from @params.
 865  * If @permit_abbrev, the first key=value in @params may omit key=,
 866  * and is treated as if key was @list->implied_opt_name.
 867  * On error, store an error object through @errp if non-null.
 868  * Return the new QemuOpts on success, null pointer on error.
 869  */
 870 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
 871                           bool permit_abbrev, Error **errp)
 872 {
 873     return opts_parse(list, params, permit_abbrev, false, errp);
 874 }
 875
 876 /**
 877  * Create a QemuOpts in @list and with options parsed from @params.
 878  * If @permit_abbrev, the first key=value in @params may omit key=,
 879  * and is treated as if key was @list->implied_opt_name.
 880  * Report errors with error_report_err().  This is inappropriate in
 881  * QMP context.  Do not use this function there!
 882  * Return the new QemuOpts on success, null pointer on error.
 883  */
 884 QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
 885                                   bool permit_abbrev)
 886 {
 887     Error *err = NULL;
 888     QemuOpts *opts;
 889
 890     opts = opts_parse(list, params, permit_abbrev, false, &err);
 891     if (err) {
 892         error_report_err(err);
 893     }
 894     return opts;
 895 }
 896
 897 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,
 898                             int permit_abbrev)
 899 {
 900     QemuOpts *opts;
 901
 902     opts = opts_parse(list, params, permit_abbrev, true, NULL);
 903     assert(opts);
 904 }
 905
 906 typedef struct OptsFromQDictState {
 907     QemuOpts *opts;
 908     Error **errp;
 909 } OptsFromQDictState;
 910
 911 static void qemu_opts_from_qdict_1(const char *key, QObject *obj, void *opaque)
 912 {
 913     OptsFromQDictState *state = opaque;
 914     char buf[32], *tmp = NULL;
 915     const char *value;
 916
 917     if (!strcmp(key, "id") || *state->errp) {
 918         return;
 919     }
 920
 921     switch (qobject_type(obj)) {
 922     case QTYPE_QSTRING:
 923         value = qstring_get_str(qobject_to(QString, obj));
 924         break;
 925     case QTYPE_QNUM:
 926         tmp = qnum_to_string(qobject_to(QNum, obj));
 927         value = tmp;
 928         break;
 929     case QTYPE_QBOOL:
 930         pstrcpy(buf, sizeof(buf),
 931                 qbool_get_bool(qobject_to(QBool, obj)) ? "on" : "off");
 932         value = buf;
 933         break;
 934     default:
 935         return;
 936     }
 937
 938     qemu_opt_set(state->opts, key, value, state->errp);
 939     g_free(tmp);
 940 }
 941
 942 /*
 943  * Create QemuOpts from a QDict.
 944  * Use value of key "id" as ID if it exists and is a QString.  Only
 945  * QStrings, QNums and QBools are copied.  Entries with other types
 946  * are silently ignored.
 947  */
 948 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
 949                                Error **errp)
 950 {
 951     OptsFromQDictState state;
 952     Error *local_err = NULL;
 953     QemuOpts *opts;
 954
 955     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1,
 956                             &local_err);
 957     if (local_err) {
 958         error_propagate(errp, local_err);
 959         return NULL;
 960     }
 961
 962     assert(opts != NULL);
 963
 964     state.errp = &local_err;
 965     state.opts = opts;
 966     qdict_iter(qdict, qemu_opts_from_qdict_1, &state);
 967     if (local_err) {
 968         error_propagate(errp, local_err);
 969         qemu_opts_del(opts);
 970         return NULL;
 971     }
 972
 973     return opts;
 974 }
 975
 976 /*
 977  * Adds all QDict entries to the QemuOpts that can be added and removes them
 978  * from the QDict. When this function returns, the QDict contains only those
 979  * entries that couldn't be added to the QemuOpts.
 980  */
 981 void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
 982 {
 983     const QDictEntry *entry, *next;
 984
 985     entry = qdict_first(qdict);
 986
 987     while (entry != NULL) {
 988         Error *local_err = NULL;
 989         OptsFromQDictState state = {
 990             .errp = &local_err,
 991             .opts = opts,
 992         };
 993
 994         next = qdict_next(qdict, entry);
 995
 996         if (find_desc_by_name(opts->list->desc, entry->key)) {
 997             qemu_opts_from_qdict_1(entry->key, entry->value, &state);
 998             if (local_err) {
 999                 error_propagate(errp, local_err);
1000                 return;
1001             } else {
1002                 qdict_del(qdict, entry->key);
1003             }
1004         }
1005
1006         entry = next;
1007     }
1008 }
1009
1010 /*
1011  * Convert from QemuOpts to QDict. The QDict values are of type QString.
1012  *
1013  * If @list is given, only add those options to the QDict that are contained in
1014  * the list. If @del is true, any options added to the QDict are removed from
1015  * the QemuOpts, otherwise they remain there.
1016  *
1017  * If two options in @opts have the same name, they are processed in order
1018  * so that the last one wins (consistent with the reverse iteration in
1019  * qemu_opt_find()), but all of them are deleted if @del is true.
1020  *
1021  * TODO We'll want to use types appropriate for opt->desc->type, but
1022  * this is enough for now.
1023  */
1024 QDict *qemu_opts_to_qdict_filtered(QemuOpts *opts, QDict *qdict,
1025                                    QemuOptsList *list, bool del)
1026 {
1027     QemuOpt *opt, *next;
1028
1029     if (!qdict) {
1030         qdict = qdict_new();
1031     }
1032     if (opts->id) {
1033         qdict_put_str(qdict, "id", opts->id);
1034     }
1035     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next) {
1036         if (list) {
1037             QemuOptDesc *desc;
1038             bool found = false;
1039             for (desc = list->desc; desc->name; desc++) {
1040                 if (!strcmp(desc->name, opt->name)) {
1041                     found = true;
1042                     break;
1043                 }
1044             }
1045             if (!found) {
1046                 continue;
1047             }
1048         }
1049         qdict_put_str(qdict, opt->name, opt->str);
1050         if (del) {
1051             qemu_opt_del(opt);
1052         }
1053     }
1054     return qdict;
1055 }
1056
1057 /* Copy all options in a QemuOpts to the given QDict. See
1058  * qemu_opts_to_qdict_filtered() for details. */
1059 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
1060 {
1061     return qemu_opts_to_qdict_filtered(opts, qdict, NULL, false);
1062 }
1063
1064 /* Validate parsed opts against descriptions where no
1065  * descriptions were provided in the QemuOptsList.
1066  */
1067 void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
1068 {
1069     QemuOpt *opt;
1070     Error *local_err = NULL;
1071
1072     assert(opts_accepts_any(opts));
1073
1074     QTAILQ_FOREACH(opt, &opts->head, next) {
1075         opt->desc = find_desc_by_name(desc, opt->name);
1076         if (!opt->desc) {
1077             error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
1078             return;
1079         }
1080
1081         qemu_opt_parse(opt, &local_err);
1082         if (local_err) {
1083             error_propagate(errp, local_err);
1084             return;
1085         }
1086     }
1087 }
1088
1089 /**
1090  * For each member of @list, call @func(@opaque, member, @errp).
1091  * Call it with the current location temporarily set to the member's.
1092  * @func() may store an Error through @errp, but must return non-zero then.
1093  * When @func() returns non-zero, break the loop and return that value.
1094  * Return zero when the loop completes.
1095  */
1096 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
1097                       void *opaque, Error **errp)
1098 {
1099     Location loc;
1100     QemuOpts *opts;
1101     int rc = 0;
1102
1103     loc_push_none(&loc);
1104     QTAILQ_FOREACH(opts, &list->head, next) {
1105         loc_restore(&opts->loc);
1106         rc = func(opaque, opts, errp);
1107         if (rc) {
1108             break;
1109         }
1110         assert(!errp || !*errp);
1111     }
1112     loc_pop(&loc);
1113     return rc;
1114 }
1115
1116 static size_t count_opts_list(QemuOptsList *list)
1117 {
1118     QemuOptDesc *desc = NULL;
1119     size_t num_opts = 0;
1120
1121     if (!list) {
1122         return 0;
1123     }
1124
1125     desc = list->desc;
1126     while (desc && desc->name) {
1127         num_opts++;
1128         desc++;
1129     }
1130
1131     return num_opts;
1132 }
1133
1134 void qemu_opts_free(QemuOptsList *list)
1135 {
1136     g_free(list);
1137 }
1138
1139 /* Realloc dst option list and append options from an option list (list)
1140  * to it. dst could be NULL or a malloced list.
1141  * The lifetime of dst must be shorter than the input list because the
1142  * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
1143  */
1144 QemuOptsList *qemu_opts_append(QemuOptsList *dst,
1145                                QemuOptsList *list)
1146 {
1147     size_t num_opts, num_dst_opts;
1148     QemuOptDesc *desc;
1149     bool need_init = false;
1150     bool need_head_update;
1151
1152     if (!list) {
1153         return dst;
1154     }
1155
1156     /* If dst is NULL, after realloc, some area of dst should be initialized
1157      * before adding options to it.
1158      */
1159     if (!dst) {
1160         need_init = true;
1161         need_head_update = true;
1162     } else {
1163         /* Moreover, even if dst is not NULL, the realloc may move it to a
1164          * different address in which case we may get a stale tail pointer
1165          * in dst->head. */
1166         need_head_update = QTAILQ_EMPTY(&dst->head);
1167     }
1168
1169     num_opts = count_opts_list(dst);
1170     num_dst_opts = num_opts;
1171     num_opts += count_opts_list(list);
1172     dst = g_realloc(dst, sizeof(QemuOptsList) +
1173                     (num_opts + 1) * sizeof(QemuOptDesc));
1174     if (need_init) {
1175         dst->name = NULL;
1176         dst->implied_opt_name = NULL;
1177         dst->merge_lists = false;
1178     }
1179     if (need_head_update) {
1180         QTAILQ_INIT(&dst->head);
1181     }
1182     dst->desc[num_dst_opts].name = NULL;
1183
1184     /* append list->desc to dst->desc */
1185     if (list) {
1186         desc = list->desc;
1187         while (desc && desc->name) {
1188             if (find_desc_by_name(dst->desc, desc->name) == NULL) {
1189                 dst->desc[num_dst_opts++] = *desc;
1190                 dst->desc[num_dst_opts].name = NULL;
1191             }
1192             desc++;
1193         }
1194     }
1195
1196     return dst;
1197 }