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 <stdio.h>
  27 #include <string.h>
  28
  29 #include "qemu-common.h"
  30 #include "qemu-error.h"
  31 #include "qemu-objects.h"
  32 #include "qemu-option.h"
  33 #include "qerror.h"
  34
  35 /*
  36  * Extracts the name of an option from the parameter string (p points at the
  37  * first byte of the option name)
  38  *
  39  * The option name is delimited by delim (usually , or =) or the string end
  40  * and is copied into buf. If the option name is longer than buf_size, it is
  41  * truncated. buf is always zero terminated.
  42  *
  43  * The return value is the position of the delimiter/zero byte after the option
  44  * name in p.
  45  */
  46 const char *get_opt_name(char *buf, int buf_size, const char *p, char delim)
  47 {
  48     char *q;
  49
  50     q = buf;
  51     while (*p != '\0' && *p != delim) {
  52         if (q && (q - buf) < buf_size - 1)
  53             *q++ = *p;
  54         p++;
  55     }
  56     if (q)
  57         *q = '\0';
  58
  59     return p;
  60 }
  61
  62 /*
  63  * Extracts the value of an option from the parameter string p (p points at the
  64  * first byte of the option value)
  65  *
  66  * This function is comparable to get_opt_name with the difference that the
  67  * delimiter is fixed to be comma which starts a new option. To specify an
  68  * option value that contains commas, double each comma.
  69  */
  70 const char *get_opt_value(char *buf, int buf_size, const char *p)
  71 {
  72     char *q;
  73
  74     q = buf;
  75     while (*p != '\0') {
  76         if (*p == ',') {
  77             if (*(p + 1) != ',')
  78                 break;
  79             p++;
  80         }
  81         if (q && (q - buf) < buf_size - 1)
  82             *q++ = *p;
  83         p++;
  84     }
  85     if (q)
  86         *q = '\0';
  87
  88     return p;
  89 }
  90
  91 int get_next_param_value(char *buf, int buf_size,
  92                          const char *tag, const char **pstr)
  93 {
  94     const char *p;
  95     char option[128];
  96
  97     p = *pstr;
  98     for(;;) {
  99         p = get_opt_name(option, sizeof(option), p, '=');
 100         if (*p != '=')
 101             break;
 102         p++;
 103         if (!strcmp(tag, option)) {
 104             *pstr = get_opt_value(buf, buf_size, p);
 105             if (**pstr == ',') {
 106                 (*pstr)++;
 107             }
 108             return strlen(buf);
 109         } else {
 110             p = get_opt_value(NULL, 0, p);
 111         }
 112         if (*p != ',')
 113             break;
 114         p++;
 115     }
 116     return 0;
 117 }
 118
 119 int get_param_value(char *buf, int buf_size,
 120                     const char *tag, const char *str)
 121 {
 122     return get_next_param_value(buf, buf_size, tag, &str);
 123 }
 124
 125 int check_params(char *buf, int buf_size,
 126                  const char * const *params, const char *str)
 127 {
 128     const char *p;
 129     int i;
 130
 131     p = str;
 132     while (*p != '\0') {
 133         p = get_opt_name(buf, buf_size, p, '=');
 134         if (*p != '=') {
 135             return -1;
 136         }
 137         p++;
 138         for (i = 0; params[i] != NULL; i++) {
 139             if (!strcmp(params[i], buf)) {
 140                 break;
 141             }
 142         }
 143         if (params[i] == NULL) {
 144             return -1;
 145         }
 146         p = get_opt_value(NULL, 0, p);
 147         if (*p != ',') {
 148             break;
 149         }
 150         p++;
 151     }
 152     return 0;
 153 }
 154
 155 /*
 156  * Searches an option list for an option with the given name
 157  */
 158 QEMUOptionParameter *get_option_parameter(QEMUOptionParameter *list,
 159     const char *name)
 160 {
 161     while (list && list->name) {
 162         if (!strcmp(list->name, name)) {
 163             return list;
 164         }
 165         list++;
 166     }
 167
 168     return NULL;
 169 }
 170
 171 static int parse_option_bool(const char *name, const char *value, int *ret)
 172 {
 173     if (value != NULL) {
 174         if (!strcmp(value, "on")) {
 175             *ret = 1;
 176         } else if (!strcmp(value, "off")) {
 177             *ret = 0;
 178         } else {
 179             qerror_report(QERR_INVALID_PARAMETER_VALUE, name, "'on' or 'off'");
 180             return -1;
 181         }
 182     } else {
 183         *ret = 1;
 184     }
 185     return 0;
 186 }
 187
 188 static int parse_option_number(const char *name, const char *value, uint64_t *ret)
 189 {
 190     char *postfix;
 191     uint64_t number;
 192
 193     if (value != NULL) {
 194         number = strtoull(value, &postfix, 0);
 195         if (*postfix != '\0') {
 196             qerror_report(QERR_INVALID_PARAMETER_VALUE, name, "a number");
 197             return -1;
 198         }
 199         *ret = number;
 200     } else {
 201         qerror_report(QERR_INVALID_PARAMETER_VALUE, name, "a number");
 202         return -1;
 203     }
 204     return 0;
 205 }
 206
 207 static int parse_option_size(const char *name, const char *value, uint64_t *ret)
 208 {
 209     char *postfix;
 210     double sizef;
 211
 212     if (value != NULL) {
 213         sizef = strtod(value, &postfix);
 214         switch (*postfix) {
 215         case 'T':
 216             sizef *= 1024;
 217         case 'G':
 218             sizef *= 1024;
 219         case 'M':
 220             sizef *= 1024;
 221         case 'K':
 222         case 'k':
 223             sizef *= 1024;
 224         case 'b':
 225         case '\0':
 226             *ret = (uint64_t) sizef;
 227             break;
 228         default:
 229             qerror_report(QERR_INVALID_PARAMETER_VALUE, name, "a size");
 230             error_printf_unless_qmp("You may use k, M, G or T suffixes for "
 231                     "kilobytes, megabytes, gigabytes and terabytes.\n");
 232             return -1;
 233         }
 234     } else {
 235         qerror_report(QERR_INVALID_PARAMETER_VALUE, name, "a size");
 236         return -1;
 237     }
 238     return 0;
 239 }
 240
 241 /*
 242  * Sets the value of a parameter in a given option list. The parsing of the
 243  * value depends on the type of option:
 244  *
 245  * OPT_FLAG (uses value.n):
 246  *      If no value is given, the flag is set to 1.
 247  *      Otherwise the value must be "on" (set to 1) or "off" (set to 0)
 248  *
 249  * OPT_STRING (uses value.s):
 250  *      value is strdup()ed and assigned as option value
 251  *
 252  * OPT_SIZE (uses value.n):
 253  *      The value is converted to an integer. Suffixes for kilobytes etc. are
 254  *      allowed (powers of 1024).
 255  *
 256  * Returns 0 on succes, -1 in error cases
 257  */
 258 int set_option_parameter(QEMUOptionParameter *list, const char *name,
 259     const char *value)
 260 {
 261     int flag;
 262
 263     // Find a matching parameter
 264     list = get_option_parameter(list, name);
 265     if (list == NULL) {
 266         fprintf(stderr, "Unknown option '%s'\n", name);
 267         return -1;
 268     }
 269
 270     // Process parameter
 271     switch (list->type) {
 272     case OPT_FLAG:
 273         if (parse_option_bool(name, value, &flag) == -1)
 274             return -1;
 275         list->value.n = flag;
 276         break;
 277
 278     case OPT_STRING:
 279         if (value != NULL) {
 280             list->value.s = qemu_strdup(value);
 281         } else {
 282             fprintf(stderr, "Option '%s' needs a parameter\n", name);
 283             return -1;
 284         }
 285         break;
 286
 287     case OPT_SIZE:
 288         if (parse_option_size(name, value, &list->value.n) == -1)
 289             return -1;
 290         break;
 291
 292     default:
 293         fprintf(stderr, "Bug: Option '%s' has an unknown type\n", name);
 294         return -1;
 295     }
 296
 297     return 0;
 298 }
 299
 300 /*
 301  * Sets the given parameter to an integer instead of a string.
 302  * This function cannot be used to set string options.
 303  *
 304  * Returns 0 on success, -1 in error cases
 305  */
 306 int set_option_parameter_int(QEMUOptionParameter *list, const char *name,
 307     uint64_t value)
 308 {
 309     // Find a matching parameter
 310     list = get_option_parameter(list, name);
 311     if (list == NULL) {
 312         fprintf(stderr, "Unknown option '%s'\n", name);
 313         return -1;
 314     }
 315
 316     // Process parameter
 317     switch (list->type) {
 318     case OPT_FLAG:
 319     case OPT_NUMBER:
 320     case OPT_SIZE:
 321         list->value.n = value;
 322         break;
 323
 324     default:
 325         return -1;
 326     }
 327
 328     return 0;
 329 }
 330
 331 /*
 332  * Frees a option list. If it contains strings, the strings are freed as well.
 333  */
 334 void free_option_parameters(QEMUOptionParameter *list)
 335 {
 336     QEMUOptionParameter *cur = list;
 337
 338     while (cur && cur->name) {
 339         if (cur->type == OPT_STRING) {
 340             qemu_free(cur->value.s);
 341         }
 342         cur++;
 343     }
 344
 345     qemu_free(list);
 346 }
 347
 348 /*
 349  * Count valid options in list
 350  */
 351 static size_t count_option_parameters(QEMUOptionParameter *list)
 352 {
 353     size_t num_options = 0;
 354
 355     while (list && list->name) {
 356         num_options++;
 357         list++;
 358     }
 359
 360     return num_options;
 361 }
 362
 363 /*
 364  * Append an option list (list) to an option list (dest).
 365  *
 366  * If dest is NULL, a new copy of list is created.
 367  *
 368  * Returns a pointer to the first element of dest (or the newly allocated copy)
 369  */
 370 QEMUOptionParameter *append_option_parameters(QEMUOptionParameter *dest,
 371     QEMUOptionParameter *list)
 372 {
 373     size_t num_options, num_dest_options;
 374
 375     num_options = count_option_parameters(dest);
 376     num_dest_options = num_options;
 377
 378     num_options += count_option_parameters(list);
 379
 380     dest = qemu_realloc(dest, (num_options + 1) * sizeof(QEMUOptionParameter));
 381     dest[num_dest_options].name = NULL;
 382
 383     while (list && list->name) {
 384         if (get_option_parameter(dest, list->name) == NULL) {
 385             dest[num_dest_options++] = *list;
 386             dest[num_dest_options].name = NULL;
 387         }
 388         list++;
 389     }
 390
 391     return dest;
 392 }
 393
 394 /*
 395  * Parses a parameter string (param) into an option list (dest).
 396  *
 397  * list is the templace is. If dest is NULL, a new copy of list is created for
 398  * it. If list is NULL, this function fails.
 399  *
 400  * A parameter string consists of one or more parameters, separated by commas.
 401  * Each parameter consists of its name and possibly of a value. In the latter
 402  * case, the value is delimited by an = character. To specify a value which
 403  * contains commas, double each comma so it won't be recognized as the end of
 404  * the parameter.
 405  *
 406  * For more details of the parsing see above.
 407  *
 408  * Returns a pointer to the first element of dest (or the newly allocated copy)
 409  * or NULL in error cases
 410  */
 411 QEMUOptionParameter *parse_option_parameters(const char *param,
 412     QEMUOptionParameter *list, QEMUOptionParameter *dest)
 413 {
 414     QEMUOptionParameter *allocated = NULL;
 415     char name[256];
 416     char value[256];
 417     char *param_delim, *value_delim;
 418     char next_delim;
 419     size_t num_options;
 420
 421     if (list == NULL) {
 422         return NULL;
 423     }
 424
 425     if (dest == NULL) {
 426         // Count valid options
 427         num_options = count_option_parameters(list);
 428
 429         // Create a copy of the option list to fill in values
 430         dest = qemu_mallocz((num_options + 1) * sizeof(QEMUOptionParameter));
 431         allocated = dest;
 432         memcpy(dest, list, (num_options + 1) * sizeof(QEMUOptionParameter));
 433     }
 434
 435     while (*param) {
 436
 437         // Find parameter name and value in the string
 438         param_delim = strchr(param, ',');
 439         value_delim = strchr(param, '=');
 440
 441         if (value_delim && (value_delim < param_delim || !param_delim)) {
 442             next_delim = '=';
 443         } else {
 444             next_delim = ',';
 445             value_delim = NULL;
 446         }
 447
 448         param = get_opt_name(name, sizeof(name), param, next_delim);
 449         if (value_delim) {
 450             param = get_opt_value(value, sizeof(value), param + 1);
 451         }
 452         if (*param != '\0') {
 453             param++;
 454         }
 455
 456         // Set the parameter
 457         if (set_option_parameter(dest, name, value_delim ? value : NULL)) {
 458             goto fail;
 459         }
 460     }
 461
 462     return dest;
 463
 464 fail:
 465     // Only free the list if it was newly allocated
 466     free_option_parameters(allocated);
 467     return NULL;
 468 }
 469
 470 /*
 471  * Prints all options of a list that have a value to stdout
 472  */
 473 void print_option_parameters(QEMUOptionParameter *list)
 474 {
 475     while (list && list->name) {
 476         switch (list->type) {
 477             case OPT_STRING:
 478                  if (list->value.s != NULL) {
 479                      printf("%s='%s' ", list->name, list->value.s);
 480                  }
 481                 break;
 482             case OPT_FLAG:
 483                 printf("%s=%s ", list->name, list->value.n ? "on" : "off");
 484                 break;
 485             case OPT_SIZE:
 486             case OPT_NUMBER:
 487                 printf("%s=%" PRId64 " ", list->name, list->value.n);
 488                 break;
 489             default:
 490                 printf("%s=(unkown type) ", list->name);
 491                 break;
 492         }
 493         list++;
 494     }
 495 }
 496
 497 /*
 498  * Prints an overview of all available options
 499  */
 500 void print_option_help(QEMUOptionParameter *list)
 501 {
 502     printf("Supported options:\n");
 503     while (list && list->name) {
 504         printf("%-16s %s\n", list->name,
 505             list->help ? list->help : "No description available");
 506         list++;
 507     }
 508 }
 509
 510 /* ------------------------------------------------------------------ */
 511
 512 struct QemuOpt {
 513     const char   *name;
 514     const char   *str;
 515
 516     const QemuOptDesc *desc;
 517     union {
 518         int      boolean;
 519         uint64_t uint;
 520     } value;
 521
 522     QemuOpts     *opts;
 523     QTAILQ_ENTRY(QemuOpt) next;
 524 };
 525
 526 struct QemuOpts {
 527     char *id;
 528     QemuOptsList *list;
 529     Location loc;
 530     QTAILQ_HEAD(QemuOptHead, QemuOpt) head;
 531     QTAILQ_ENTRY(QemuOpts) next;
 532 };
 533
 534 static QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
 535 {
 536     QemuOpt *opt;
 537
 538     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
 539         if (strcmp(opt->name, name) != 0)
 540             continue;
 541         return opt;
 542     }
 543     return NULL;
 544 }
 545
 546 const char *qemu_opt_get(QemuOpts *opts, const char *name)
 547 {
 548     QemuOpt *opt = qemu_opt_find(opts, name);
 549     return opt ? opt->str : NULL;
 550 }
 551
 552 int qemu_opt_get_bool(QemuOpts *opts, const char *name, int defval)
 553 {
 554     QemuOpt *opt = qemu_opt_find(opts, name);
 555
 556     if (opt == NULL)
 557         return defval;
 558     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
 559     return opt->value.boolean;
 560 }
 561
 562 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
 563 {
 564     QemuOpt *opt = qemu_opt_find(opts, name);
 565
 566     if (opt == NULL)
 567         return defval;
 568     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
 569     return opt->value.uint;
 570 }
 571
 572 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
 573 {
 574     QemuOpt *opt = qemu_opt_find(opts, name);
 575
 576     if (opt == NULL)
 577         return defval;
 578     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
 579     return opt->value.uint;
 580 }
 581
 582 static int qemu_opt_parse(QemuOpt *opt)
 583 {
 584     if (opt->desc == NULL)
 585         return 0;
 586     switch (opt->desc->type) {
 587     case QEMU_OPT_STRING:
 588         /* nothing */
 589         return 0;
 590     case QEMU_OPT_BOOL:
 591         return parse_option_bool(opt->name, opt->str, &opt->value.boolean);
 592     case QEMU_OPT_NUMBER:
 593         return parse_option_number(opt->name, opt->str, &opt->value.uint);
 594     case QEMU_OPT_SIZE:
 595         return parse_option_size(opt->name, opt->str, &opt->value.uint);
 596     default:
 597         abort();
 598     }
 599 }
 600
 601 static void qemu_opt_del(QemuOpt *opt)
 602 {
 603     QTAILQ_REMOVE(&opt->opts->head, opt, next);
 604     qemu_free((/* !const */ char*)opt->name);
 605     qemu_free((/* !const */ char*)opt->str);
 606     qemu_free(opt);
 607 }
 608
 609 int qemu_opt_set(QemuOpts *opts, const char *name, const char *value)
 610 {
 611     QemuOpt *opt;
 612     const QemuOptDesc *desc = opts->list->desc;
 613     int i;
 614
 615     for (i = 0; desc[i].name != NULL; i++) {
 616         if (strcmp(desc[i].name, name) == 0) {
 617             break;
 618         }
 619     }
 620     if (desc[i].name == NULL) {
 621         if (i == 0) {
 622             /* empty list -> allow any */;
 623         } else {
 624             qerror_report(QERR_INVALID_PARAMETER, name);
 625             return -1;
 626         }
 627     }
 628
 629     opt = qemu_mallocz(sizeof(*opt));
 630     opt->name = qemu_strdup(name);
 631     opt->opts = opts;
 632     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 633     if (desc[i].name != NULL) {
 634         opt->desc = desc+i;
 635     }
 636     if (value) {
 637         opt->str = qemu_strdup(value);
 638     }
 639     if (qemu_opt_parse(opt) < 0) {
 640         qemu_opt_del(opt);
 641         return -1;
 642     }
 643     return 0;
 644 }
 645
 646 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
 647                      int abort_on_failure)
 648 {
 649     QemuOpt *opt;
 650     int rc = 0;
 651
 652     QTAILQ_FOREACH(opt, &opts->head, next) {
 653         rc = func(opt->name, opt->str, opaque);
 654         if (abort_on_failure  &&  rc != 0)
 655             break;
 656     }
 657     return rc;
 658 }
 659
 660 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
 661 {
 662     QemuOpts *opts;
 663
 664     QTAILQ_FOREACH(opts, &list->head, next) {
 665         if (!opts->id) {
 666             continue;
 667         }
 668         if (strcmp(opts->id, id) != 0) {
 669             continue;
 670         }
 671         return opts;
 672     }
 673     return NULL;
 674 }
 675
 676 static int id_wellformed(const char *id)
 677 {
 678     int i;
 679
 680     if (!qemu_isalpha(id[0])) {
 681         return 0;
 682     }
 683     for (i = 1; id[i]; i++) {
 684         if (!qemu_isalnum(id[i]) && !strchr("-._", id[i])) {
 685             return 0;
 686         }
 687     }
 688     return 1;
 689 }
 690
 691 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id, int fail_if_exists)
 692 {
 693     QemuOpts *opts = NULL;
 694
 695     if (id) {
 696         if (!id_wellformed(id)) {
 697             qerror_report(QERR_INVALID_PARAMETER_VALUE, "id", "an identifier");
 698             error_printf_unless_qmp("Identifiers consist of letters, digits, '-', '.', '_', starting with a letter.\n");
 699             return NULL;
 700         }
 701         opts = qemu_opts_find(list, id);
 702         if (opts != NULL) {
 703             if (fail_if_exists) {
 704                 qerror_report(QERR_DUPLICATE_ID, id, list->name);
 705                 return NULL;
 706             } else {
 707                 return opts;
 708             }
 709         }
 710     }
 711     opts = qemu_mallocz(sizeof(*opts));
 712     if (id) {
 713         opts->id = qemu_strdup(id);
 714     }
 715     opts->list = list;
 716     loc_save(&opts->loc);
 717     QTAILQ_INIT(&opts->head);
 718     QTAILQ_INSERT_TAIL(&list->head, opts, next);
 719     return opts;
 720 }
 721
 722 void qemu_opts_reset(QemuOptsList *list)
 723 {
 724     QemuOpts *opts, *next_opts;
 725
 726     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
 727         qemu_opts_del(opts);
 728     }
 729 }
 730
 731 void qemu_opts_loc_restore(QemuOpts *opts)
 732 {
 733     loc_restore(&opts->loc);
 734 }
 735
 736 int qemu_opts_set(QemuOptsList *list, const char *id,
 737                   const char *name, const char *value)
 738 {
 739     QemuOpts *opts;
 740
 741     opts = qemu_opts_create(list, id, 1);
 742     if (opts == NULL) {
 743         return -1;
 744     }
 745     return qemu_opt_set(opts, name, value);
 746 }
 747
 748 const char *qemu_opts_id(QemuOpts *opts)
 749 {
 750     return opts->id;
 751 }
 752
 753 void qemu_opts_del(QemuOpts *opts)
 754 {
 755     QemuOpt *opt;
 756
 757     for (;;) {
 758         opt = QTAILQ_FIRST(&opts->head);
 759         if (opt == NULL)
 760             break;
 761         qemu_opt_del(opt);
 762     }
 763     QTAILQ_REMOVE(&opts->list->head, opts, next);
 764     qemu_free(opts->id);
 765     qemu_free(opts);
 766 }
 767
 768 int qemu_opts_print(QemuOpts *opts, void *dummy)
 769 {
 770     QemuOpt *opt;
 771
 772     fprintf(stderr, "%s: %s:", opts->list->name,
 773             opts->id ? opts->id : "<noid>");
 774     QTAILQ_FOREACH(opt, &opts->head, next) {
 775         fprintf(stderr, " %s=\"%s\"", opt->name, opt->str);
 776     }
 777     fprintf(stderr, "\n");
 778     return 0;
 779 }
 780
 781 int qemu_opts_do_parse(QemuOpts *opts, const char *params, const char *firstname)
 782 {
 783     char option[128], value[1024];
 784     const char *p,*pe,*pc;
 785
 786     for (p = params; *p != '\0'; p++) {
 787         pe = strchr(p, '=');
 788         pc = strchr(p, ',');
 789         if (!pe || (pc && pc < pe)) {
 790             /* found "foo,more" */
 791             if (p == params && firstname) {
 792                 /* implicitly named first option */
 793                 pstrcpy(option, sizeof(option), firstname);
 794                 p = get_opt_value(value, sizeof(value), p);
 795             } else {
 796                 /* option without value, probably a flag */
 797                 p = get_opt_name(option, sizeof(option), p, ',');
 798                 if (strncmp(option, "no", 2) == 0) {
 799                     memmove(option, option+2, strlen(option+2)+1);
 800                     pstrcpy(value, sizeof(value), "off");
 801                 } else {
 802                     pstrcpy(value, sizeof(value), "on");
 803                 }
 804             }
 805         } else {
 806             /* found "foo=bar,more" */
 807             p = get_opt_name(option, sizeof(option), p, '=');
 808             if (*p != '=') {
 809                 break;
 810             }
 811             p++;
 812             p = get_opt_value(value, sizeof(value), p);
 813         }
 814         if (strcmp(option, "id") != 0) {
 815             /* store and parse */
 816             if (qemu_opt_set(opts, option, value) == -1) {
 817                 return -1;
 818             }
 819         }
 820         if (*p != ',') {
 821             break;
 822         }
 823     }
 824     return 0;
 825 }
 826
 827 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
 828                           int permit_abbrev)
 829 {
 830     const char *firstname;
 831     char value[1024], *id = NULL;
 832     const char *p;
 833     QemuOpts *opts;
 834
 835     assert(!permit_abbrev || list->implied_opt_name);
 836     firstname = permit_abbrev ? list->implied_opt_name : NULL;
 837
 838     if (strncmp(params, "id=", 3) == 0) {
 839         get_opt_value(value, sizeof(value), params+3);
 840         id = value;
 841     } else if ((p = strstr(params, ",id=")) != NULL) {
 842         get_opt_value(value, sizeof(value), p+4);
 843         id = value;
 844     }
 845     opts = qemu_opts_create(list, id, 1);
 846     if (opts == NULL)
 847         return NULL;
 848
 849     if (qemu_opts_do_parse(opts, params, firstname) != 0) {
 850         qemu_opts_del(opts);
 851         return NULL;
 852     }
 853
 854     return opts;
 855 }
 856
 857 static void qemu_opts_from_qdict_1(const char *key, QObject *obj, void *opaque)
 858 {
 859     char buf[32];
 860     const char *value;
 861     int n;
 862
 863     if (!strcmp(key, "id")) {
 864         return;
 865     }
 866
 867     switch (qobject_type(obj)) {
 868     case QTYPE_QSTRING:
 869         value = qstring_get_str(qobject_to_qstring(obj));
 870         break;
 871     case QTYPE_QINT:
 872         n = snprintf(buf, sizeof(buf), "%" PRId64,
 873                      qint_get_int(qobject_to_qint(obj)));
 874         assert(n < sizeof(buf));
 875         value = buf;
 876         break;
 877     case QTYPE_QFLOAT:
 878         n = snprintf(buf, sizeof(buf), "%.17g",
 879                      qfloat_get_double(qobject_to_qfloat(obj)));
 880         assert(n < sizeof(buf));
 881         value = buf;
 882         break;
 883     case QTYPE_QBOOL:
 884         pstrcpy(buf, sizeof(buf),
 885                 qbool_get_int(qobject_to_qbool(obj)) ? "on" : "off");
 886         value = buf;
 887         break;
 888     default:
 889         return;
 890     }
 891     qemu_opt_set(opaque, key, value);
 892 }
 893
 894 /*
 895  * Create QemuOpts from a QDict.
 896  * Use value of key "id" as ID if it exists and is a QString.
 897  * Only QStrings, QInts, QFloats and QBools are copied.  Entries with
 898  * other types are silently ignored.
 899  */
 900 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict)
 901 {
 902     QemuOpts *opts;
 903
 904     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1);
 905     if (opts == NULL)
 906         return NULL;
 907
 908     qdict_iter(qdict, qemu_opts_from_qdict_1, opts);
 909     return opts;
 910 }
 911
 912 /*
 913  * Convert from QemuOpts to QDict.
 914  * The QDict values are of type QString.
 915  * TODO We'll want to use types appropriate for opt->desc->type, but
 916  * this is enough for now.
 917  */
 918 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
 919 {
 920     QemuOpt *opt;
 921     QObject *val;
 922
 923     if (!qdict) {
 924         qdict = qdict_new();
 925     }
 926     if (opts->id) {
 927         qdict_put(qdict, "id", qstring_from_str(opts->id));
 928     }
 929     QTAILQ_FOREACH(opt, &opts->head, next) {
 930         val = QOBJECT(qstring_from_str(opt->str));
 931         qdict_put_obj(qdict, opt->name, val);
 932     }
 933     return qdict;
 934 }
 935
 936 /* Validate parsed opts against descriptions where no
 937  * descriptions were provided in the QemuOptsList.
 938  */
 939 int qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc)
 940 {
 941     QemuOpt *opt;
 942
 943     assert(opts->list->desc[0].name == NULL);
 944
 945     QTAILQ_FOREACH(opt, &opts->head, next) {
 946         int i;
 947
 948         for (i = 0; desc[i].name != NULL; i++) {
 949             if (strcmp(desc[i].name, opt->name) == 0) {
 950                 break;
 951             }
 952         }
 953         if (desc[i].name == NULL) {
 954             qerror_report(QERR_INVALID_PARAMETER, opt->name);
 955             return -1;
 956         }
 957
 958         opt->desc = &desc[i];
 959
 960         if (qemu_opt_parse(opt) < 0) {
 961             return -1;
 962         }
 963     }
 964
 965     return 0;
 966 }
 967
 968 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
 969                       int abort_on_failure)
 970 {
 971     Location loc;
 972     QemuOpts *opts;
 973     int rc = 0;
 974
 975     loc_push_none(&loc);
 976     QTAILQ_FOREACH(opts, &list->head, next) {
 977         loc_restore(&opts->loc);
 978         rc |= func(opts, opaque);
 979         if (abort_on_failure  &&  rc != 0)
 980             break;
 981     }
 982     loc_pop(&loc);
 983     return rc;
 984 }