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, bool *invalidp, 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         if (invalidp) {
 500             *invalidp = true;
 501         }
 502         return;
 503     }
 504
 505     opt = g_malloc0(sizeof(*opt));
 506     opt->name = g_strdup(name);
 507     opt->opts = opts;
 508     if (prepend) {
 509         QTAILQ_INSERT_HEAD(&opts->head, opt, next);
 510     } else {
 511         QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 512     }
 513     opt->desc = desc;
 514     opt->str = value;
 515     qemu_opt_parse(opt, &local_err);
 516     if (local_err) {
 517         error_propagate(errp, local_err);
 518         qemu_opt_del(opt);
 519     }
 520 }
 521
 522 void qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
 523                   Error **errp)
 524 {
 525     opt_set(opts, name, g_strdup(value), false, NULL, errp);
 526 }
 527
 528 void qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
 529                        Error **errp)
 530 {
 531     QemuOpt *opt;
 532     const QemuOptDesc *desc = opts->list->desc;
 533
 534     opt = g_malloc0(sizeof(*opt));
 535     opt->desc = find_desc_by_name(desc, name);
 536     if (!opt->desc && !opts_accepts_any(opts)) {
 537         error_setg(errp, QERR_INVALID_PARAMETER, name);
 538         g_free(opt);
 539         return;
 540     }
 541
 542     opt->name = g_strdup(name);
 543     opt->opts = opts;
 544     opt->value.boolean = !!val;
 545     opt->str = g_strdup(val ? "on" : "off");
 546     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 547 }
 548
 549 void qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
 550                          Error **errp)
 551 {
 552     QemuOpt *opt;
 553     const QemuOptDesc *desc = opts->list->desc;
 554
 555     opt = g_malloc0(sizeof(*opt));
 556     opt->desc = find_desc_by_name(desc, name);
 557     if (!opt->desc && !opts_accepts_any(opts)) {
 558         error_setg(errp, QERR_INVALID_PARAMETER, name);
 559         g_free(opt);
 560         return;
 561     }
 562
 563     opt->name = g_strdup(name);
 564     opt->opts = opts;
 565     opt->value.uint = val;
 566     opt->str = g_strdup_printf("%" PRId64, val);
 567     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 568 }
 569
 570 /**
 571  * For each member of @opts, call @func(@opaque, name, value, @errp).
 572  * @func() may store an Error through @errp, but must return non-zero then.
 573  * When @func() returns non-zero, break the loop and return that value.
 574  * Return zero when the loop completes.
 575  */
 576 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
 577                      Error **errp)
 578 {
 579     QemuOpt *opt;
 580     int rc;
 581
 582     QTAILQ_FOREACH(opt, &opts->head, next) {
 583         rc = func(opaque, opt->name, opt->str, errp);
 584         if (rc) {
 585             return rc;
 586         }
 587         assert(!errp || !*errp);
 588     }
 589     return 0;
 590 }
 591
 592 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
 593 {
 594     QemuOpts *opts;
 595
 596     QTAILQ_FOREACH(opts, &list->head, next) {
 597         if (!opts->id && !id) {
 598             return opts;
 599         }
 600         if (opts->id && id && !strcmp(opts->id, id)) {
 601             return opts;
 602         }
 603     }
 604     return NULL;
 605 }
 606
 607 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
 608                            int fail_if_exists, Error **errp)
 609 {
 610     QemuOpts *opts = NULL;
 611
 612     if (id) {
 613         if (!id_wellformed(id)) {
 614             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
 615                        "an identifier");
 616             error_append_hint(errp, "Identifiers consist of letters, digits, "
 617                               "'-', '.', '_', starting with a letter.\n");
 618             return NULL;
 619         }
 620         opts = qemu_opts_find(list, id);
 621         if (opts != NULL) {
 622             if (fail_if_exists && !list->merge_lists) {
 623                 error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
 624                 return NULL;
 625             } else {
 626                 return opts;
 627             }
 628         }
 629     } else if (list->merge_lists) {
 630         opts = qemu_opts_find(list, NULL);
 631         if (opts) {
 632             return opts;
 633         }
 634     }
 635     opts = g_malloc0(sizeof(*opts));
 636     opts->id = g_strdup(id);
 637     opts->list = list;
 638     loc_save(&opts->loc);
 639     QTAILQ_INIT(&opts->head);
 640     QTAILQ_INSERT_TAIL(&list->head, opts, next);
 641     return opts;
 642 }
 643
 644 void qemu_opts_reset(QemuOptsList *list)
 645 {
 646     QemuOpts *opts, *next_opts;
 647
 648     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
 649         qemu_opts_del(opts);
 650     }
 651 }
 652
 653 void qemu_opts_loc_restore(QemuOpts *opts)
 654 {
 655     loc_restore(&opts->loc);
 656 }
 657
 658 void qemu_opts_set(QemuOptsList *list, const char *id,
 659                    const char *name, const char *value, Error **errp)
 660 {
 661     QemuOpts *opts;
 662     Error *local_err = NULL;
 663
 664     opts = qemu_opts_create(list, id, 1, &local_err);
 665     if (local_err) {
 666         error_propagate(errp, local_err);
 667         return;
 668     }
 669     qemu_opt_set(opts, name, value, errp);
 670 }
 671
 672 const char *qemu_opts_id(QemuOpts *opts)
 673 {
 674     return opts->id;
 675 }
 676
 677 /* The id string will be g_free()d by qemu_opts_del */
 678 void qemu_opts_set_id(QemuOpts *opts, char *id)
 679 {
 680     opts->id = id;
 681 }
 682
 683 void qemu_opts_del(QemuOpts *opts)
 684 {
 685     QemuOpt *opt;
 686
 687     if (opts == NULL) {
 688         return;
 689     }
 690
 691     for (;;) {
 692         opt = QTAILQ_FIRST(&opts->head);
 693         if (opt == NULL)
 694             break;
 695         qemu_opt_del(opt);
 696     }
 697     QTAILQ_REMOVE(&opts->list->head, opts, next);
 698     g_free(opts->id);
 699     g_free(opts);
 700 }
 701
 702 /* print value, escaping any commas in value */
 703 static void escaped_print(const char *value)
 704 {
 705     const char *ptr;
 706
 707     for (ptr = value; *ptr; ++ptr) {
 708         if (*ptr == ',') {
 709             putchar(',');
 710         }
 711         putchar(*ptr);
 712     }
 713 }
 714
 715 void qemu_opts_print(QemuOpts *opts, const char *separator)
 716 {
 717     QemuOpt *opt;
 718     QemuOptDesc *desc = opts->list->desc;
 719     const char *sep = "";
 720
 721     if (opts->id) {
 722         printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
 723         sep = separator;
 724     }
 725
 726     if (desc[0].name == NULL) {
 727         QTAILQ_FOREACH(opt, &opts->head, next) {
 728             printf("%s%s=", sep, opt->name);
 729             escaped_print(opt->str);
 730             sep = separator;
 731         }
 732         return;
 733     }
 734     for (; desc && desc->name; desc++) {
 735         const char *value;
 736         opt = qemu_opt_find(opts, desc->name);
 737
 738         value = opt ? opt->str : desc->def_value_str;
 739         if (!value) {
 740             continue;
 741         }
 742         if (desc->type == QEMU_OPT_STRING) {
 743             printf("%s%s=", sep, desc->name);
 744             escaped_print(value);
 745         } else if ((desc->type == QEMU_OPT_SIZE ||
 746                     desc->type == QEMU_OPT_NUMBER) && opt) {
 747             printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
 748         } else {
 749             printf("%s%s=%s", sep, desc->name, value);
 750         }
 751         sep = separator;
 752     }
 753 }
 754
 755 static void opts_do_parse(QemuOpts *opts, const char *params,
 756                           const char *firstname, bool prepend,
 757                           bool *invalidp, Error **errp)
 758 {
 759     char *option = NULL;
 760     char *value = NULL;
 761     const char *p,*pe,*pc;
 762     Error *local_err = NULL;
 763
 764     for (p = params; *p != '\0'; p++) {
 765         pe = strchr(p, '=');
 766         pc = strchr(p, ',');
 767         if (!pe || (pc && pc < pe)) {
 768             /* found "foo,more" */
 769             if (p == params && firstname) {
 770                 /* implicitly named first option */
 771                 option = g_strdup(firstname);
 772                 p = get_opt_value(p, &value);
 773             } else {
 774                 /* option without value, probably a flag */
 775                 p = get_opt_name(p, &option, ',');
 776                 if (strncmp(option, "no", 2) == 0) {
 777                     memmove(option, option+2, strlen(option+2)+1);
 778                     value = g_strdup("off");
 779                 } else {
 780                     value = g_strdup("on");
 781                 }
 782             }
 783         } else {
 784             /* found "foo=bar,more" */
 785             p = get_opt_name(p, &option, '=');
 786             assert(*p == '=');
 787             p++;
 788             p = get_opt_value(p, &value);
 789         }
 790         if (strcmp(option, "id") != 0) {
 791             /* store and parse */
 792             opt_set(opts, option, value, prepend, invalidp, &local_err);
 793             value = NULL;
 794             if (local_err) {
 795                 error_propagate(errp, local_err);
 796                 goto cleanup;
 797             }
 798         }
 799         if (*p != ',') {
 800             break;
 801         }
 802         g_free(option);
 803         g_free(value);
 804         option = value = NULL;
 805     }
 806
 807  cleanup:
 808     g_free(option);
 809     g_free(value);
 810 }
 811
 812 /**
 813  * Store options parsed from @params into @opts.
 814  * If @firstname is non-null, the first key=value in @params may omit
 815  * key=, and is treated as if key was @firstname.
 816  * On error, store an error object through @errp if non-null.
 817  */
 818 void qemu_opts_do_parse(QemuOpts *opts, const char *params,
 819                        const char *firstname, Error **errp)
 820 {
 821     opts_do_parse(opts, params, firstname, false, NULL, errp);
 822 }
 823
 824 static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
 825                             bool permit_abbrev, bool defaults,
 826                             bool *invalidp, Error **errp)
 827 {
 828     const char *firstname;
 829     char *id = NULL;
 830     const char *p;
 831     QemuOpts *opts;
 832     Error *local_err = NULL;
 833
 834     assert(!permit_abbrev || list->implied_opt_name);
 835     firstname = permit_abbrev ? list->implied_opt_name : NULL;
 836
 837     if (strncmp(params, "id=", 3) == 0) {
 838         get_opt_value(params + 3, &id);
 839     } else if ((p = strstr(params, ",id=")) != NULL) {
 840         get_opt_value(p + 4, &id);
 841     }
 842
 843     /*
 844      * This code doesn't work for defaults && !list->merge_lists: when
 845      * params has no id=, and list has an element with !opts->id, it
 846      * appends a new element instead of returning the existing opts.
 847      * However, we got no use for this case.  Guard against possible
 848      * (if unlikely) future misuse:
 849      */
 850     assert(!defaults || list->merge_lists);
 851     opts = qemu_opts_create(list, id, !defaults, &local_err);
 852     g_free(id);
 853     if (opts == NULL) {
 854         error_propagate(errp, local_err);
 855         return NULL;
 856     }
 857
 858     opts_do_parse(opts, params, firstname, defaults, invalidp, &local_err);
 859     if (local_err) {
 860         error_propagate(errp, local_err);
 861         qemu_opts_del(opts);
 862         return NULL;
 863     }
 864
 865     return opts;
 866 }
 867
 868 /**
 869  * Create a QemuOpts in @list and with options parsed from @params.
 870  * If @permit_abbrev, the first key=value in @params may omit key=,
 871  * and is treated as if key was @list->implied_opt_name.
 872  * On error, store an error object through @errp if non-null.
 873  * Return the new QemuOpts on success, null pointer on error.
 874  */
 875 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
 876                           bool permit_abbrev, Error **errp)
 877 {
 878     return opts_parse(list, params, permit_abbrev, false, NULL, errp);
 879 }
 880
 881 /**
 882  * Create a QemuOpts in @list and with options parsed from @params.
 883  * If @permit_abbrev, the first key=value in @params may omit key=,
 884  * and is treated as if key was @list->implied_opt_name.
 885  * Report errors with error_report_err().  This is inappropriate in
 886  * QMP context.  Do not use this function there!
 887  * Return the new QemuOpts on success, null pointer on error.
 888  */
 889 QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
 890                                   bool permit_abbrev)
 891 {
 892     Error *err = NULL;
 893     QemuOpts *opts;
 894     bool invalidp = false;
 895
 896     opts = opts_parse(list, params, permit_abbrev, false, &invalidp, &err);
 897     if (err) {
 898         if (invalidp && has_help_option(params)) {
 899             qemu_opts_print_help(list);
 900             error_free(err);
 901         } else {
 902             error_report_err(err);
 903         }
 904     }
 905     return opts;
 906 }
 907
 908 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,
 909                             int permit_abbrev)
 910 {
 911     QemuOpts *opts;
 912
 913     opts = opts_parse(list, params, permit_abbrev, true, NULL, NULL);
 914     assert(opts);
 915 }
 916
 917 typedef struct OptsFromQDictState {
 918     QemuOpts *opts;
 919     Error **errp;
 920 } OptsFromQDictState;
 921
 922 static void qemu_opts_from_qdict_1(const char *key, QObject *obj, void *opaque)
 923 {
 924     OptsFromQDictState *state = opaque;
 925     char buf[32], *tmp = NULL;
 926     const char *value;
 927
 928     if (!strcmp(key, "id") || *state->errp) {
 929         return;
 930     }
 931
 932     switch (qobject_type(obj)) {
 933     case QTYPE_QSTRING:
 934         value = qstring_get_str(qobject_to(QString, obj));
 935         break;
 936     case QTYPE_QNUM:
 937         tmp = qnum_to_string(qobject_to(QNum, obj));
 938         value = tmp;
 939         break;
 940     case QTYPE_QBOOL:
 941         pstrcpy(buf, sizeof(buf),
 942                 qbool_get_bool(qobject_to(QBool, obj)) ? "on" : "off");
 943         value = buf;
 944         break;
 945     default:
 946         return;
 947     }
 948
 949     qemu_opt_set(state->opts, key, value, state->errp);
 950     g_free(tmp);
 951 }
 952
 953 /*
 954  * Create QemuOpts from a QDict.
 955  * Use value of key "id" as ID if it exists and is a QString.  Only
 956  * QStrings, QNums and QBools are copied.  Entries with other types
 957  * are silently ignored.
 958  */
 959 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
 960                                Error **errp)
 961 {
 962     OptsFromQDictState state;
 963     Error *local_err = NULL;
 964     QemuOpts *opts;
 965
 966     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1,
 967                             &local_err);
 968     if (local_err) {
 969         error_propagate(errp, local_err);
 970         return NULL;
 971     }
 972
 973     assert(opts != NULL);
 974
 975     state.errp = &local_err;
 976     state.opts = opts;
 977     qdict_iter(qdict, qemu_opts_from_qdict_1, &state);
 978     if (local_err) {
 979         error_propagate(errp, local_err);
 980         qemu_opts_del(opts);
 981         return NULL;
 982     }
 983
 984     return opts;
 985 }
 986
 987 /*
 988  * Adds all QDict entries to the QemuOpts that can be added and removes them
 989  * from the QDict. When this function returns, the QDict contains only those
 990  * entries that couldn't be added to the QemuOpts.
 991  */
 992 void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
 993 {
 994     const QDictEntry *entry, *next;
 995
 996     entry = qdict_first(qdict);
 997
 998     while (entry != NULL) {
 999         Error *local_err = NULL;
1000         OptsFromQDictState state = {
1001             .errp = &local_err,
1002             .opts = opts,
1003         };
1004
1005         next = qdict_next(qdict, entry);
1006
1007         if (find_desc_by_name(opts->list->desc, entry->key)) {
1008             qemu_opts_from_qdict_1(entry->key, entry->value, &state);
1009             if (local_err) {
1010                 error_propagate(errp, local_err);
1011                 return;
1012             } else {
1013                 qdict_del(qdict, entry->key);
1014             }
1015         }
1016
1017         entry = next;
1018     }
1019 }
1020
1021 /*
1022  * Convert from QemuOpts to QDict. The QDict values are of type QString.
1023  *
1024  * If @list is given, only add those options to the QDict that are contained in
1025  * the list. If @del is true, any options added to the QDict are removed from
1026  * the QemuOpts, otherwise they remain there.
1027  *
1028  * If two options in @opts have the same name, they are processed in order
1029  * so that the last one wins (consistent with the reverse iteration in
1030  * qemu_opt_find()), but all of them are deleted if @del is true.
1031  *
1032  * TODO We'll want to use types appropriate for opt->desc->type, but
1033  * this is enough for now.
1034  */
1035 QDict *qemu_opts_to_qdict_filtered(QemuOpts *opts, QDict *qdict,
1036                                    QemuOptsList *list, bool del)
1037 {
1038     QemuOpt *opt, *next;
1039
1040     if (!qdict) {
1041         qdict = qdict_new();
1042     }
1043     if (opts->id) {
1044         qdict_put_str(qdict, "id", opts->id);
1045     }
1046     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next) {
1047         if (list) {
1048             QemuOptDesc *desc;
1049             bool found = false;
1050             for (desc = list->desc; desc->name; desc++) {
1051                 if (!strcmp(desc->name, opt->name)) {
1052                     found = true;
1053                     break;
1054                 }
1055             }
1056             if (!found) {
1057                 continue;
1058             }
1059         }
1060         qdict_put_str(qdict, opt->name, opt->str);
1061         if (del) {
1062             qemu_opt_del(opt);
1063         }
1064     }
1065     return qdict;
1066 }
1067
1068 /* Copy all options in a QemuOpts to the given QDict. See
1069  * qemu_opts_to_qdict_filtered() for details. */
1070 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
1071 {
1072     return qemu_opts_to_qdict_filtered(opts, qdict, NULL, false);
1073 }
1074
1075 /* Validate parsed opts against descriptions where no
1076  * descriptions were provided in the QemuOptsList.
1077  */
1078 void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
1079 {
1080     QemuOpt *opt;
1081     Error *local_err = NULL;
1082
1083     assert(opts_accepts_any(opts));
1084
1085     QTAILQ_FOREACH(opt, &opts->head, next) {
1086         opt->desc = find_desc_by_name(desc, opt->name);
1087         if (!opt->desc) {
1088             error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
1089             return;
1090         }
1091
1092         qemu_opt_parse(opt, &local_err);
1093         if (local_err) {
1094             error_propagate(errp, local_err);
1095             return;
1096         }
1097     }
1098 }
1099
1100 /**
1101  * For each member of @list, call @func(@opaque, member, @errp).
1102  * Call it with the current location temporarily set to the member's.
1103  * @func() may store an Error through @errp, but must return non-zero then.
1104  * When @func() returns non-zero, break the loop and return that value.
1105  * Return zero when the loop completes.
1106  */
1107 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
1108                       void *opaque, Error **errp)
1109 {
1110     Location loc;
1111     QemuOpts *opts;
1112     int rc = 0;
1113
1114     loc_push_none(&loc);
1115     QTAILQ_FOREACH(opts, &list->head, next) {
1116         loc_restore(&opts->loc);
1117         rc = func(opaque, opts, errp);
1118         if (rc) {
1119             break;
1120         }
1121         assert(!errp || !*errp);
1122     }
1123     loc_pop(&loc);
1124     return rc;
1125 }
1126
1127 static size_t count_opts_list(QemuOptsList *list)
1128 {
1129     QemuOptDesc *desc = NULL;
1130     size_t num_opts = 0;
1131
1132     if (!list) {
1133         return 0;
1134     }
1135
1136     desc = list->desc;
1137     while (desc && desc->name) {
1138         num_opts++;
1139         desc++;
1140     }
1141
1142     return num_opts;
1143 }
1144
1145 void qemu_opts_free(QemuOptsList *list)
1146 {
1147     g_free(list);
1148 }
1149
1150 /* Realloc dst option list and append options from an option list (list)
1151  * to it. dst could be NULL or a malloced list.
1152  * The lifetime of dst must be shorter than the input list because the
1153  * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
1154  */
1155 QemuOptsList *qemu_opts_append(QemuOptsList *dst,
1156                                QemuOptsList *list)
1157 {
1158     size_t num_opts, num_dst_opts;
1159     QemuOptDesc *desc;
1160     bool need_init = false;
1161     bool need_head_update;
1162
1163     if (!list) {
1164         return dst;
1165     }
1166
1167     /* If dst is NULL, after realloc, some area of dst should be initialized
1168      * before adding options to it.
1169      */
1170     if (!dst) {
1171         need_init = true;
1172         need_head_update = true;
1173     } else {
1174         /* Moreover, even if dst is not NULL, the realloc may move it to a
1175          * different address in which case we may get a stale tail pointer
1176          * in dst->head. */
1177         need_head_update = QTAILQ_EMPTY(&dst->head);
1178     }
1179
1180     num_opts = count_opts_list(dst);
1181     num_dst_opts = num_opts;
1182     num_opts += count_opts_list(list);
1183     dst = g_realloc(dst, sizeof(QemuOptsList) +
1184                     (num_opts + 1) * sizeof(QemuOptDesc));
1185     if (need_init) {
1186         dst->name = NULL;
1187         dst->implied_opt_name = NULL;
1188         dst->merge_lists = false;
1189     }
1190     if (need_head_update) {
1191         QTAILQ_INIT(&dst->head);
1192     }
1193     dst->desc[num_dst_opts].name = NULL;
1194
1195     /* append list->desc to dst->desc */
1196     if (list) {
1197         desc = list->desc;
1198         while (desc && desc->name) {
1199             if (find_desc_by_name(dst->desc, desc->name) == NULL) {
1200                 dst->desc[num_dst_opts++] = *desc;
1201                 dst->desc[num_dst_opts].name = NULL;
1202             }
1203             desc++;
1204         }
1205     }
1206
1207     return dst;
1208 }