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