xref: /openbmc/qemu/util/qemu-option.c (revision c964b660)
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 "qemu-common.h"
29 #include "qemu/error-report.h"
30 #include "qapi/qmp/types.h"
31 #include "qapi/qmp/qerror.h"
32 #include "qemu/option_int.h"
33 
34 /*
35  * Extracts the name of an option from the parameter string (p points at the
36  * first byte of the option name)
37  *
38  * The option name is delimited by delim (usually , or =) or the string end
39  * and is copied into buf. If the option name is longer than buf_size, it is
40  * truncated. buf is always zero terminated.
41  *
42  * The return value is the position of the delimiter/zero byte after the option
43  * name in p.
44  */
45 const char *get_opt_name(char *buf, int buf_size, const char *p, char delim)
46 {
47     char *q;
48 
49     q = buf;
50     while (*p != '\0' && *p != delim) {
51         if (q && (q - buf) < buf_size - 1)
52             *q++ = *p;
53         p++;
54     }
55     if (q)
56         *q = '\0';
57 
58     return p;
59 }
60 
61 /*
62  * Extracts the value of an option from the parameter string p (p points at the
63  * first byte of the option value)
64  *
65  * This function is comparable to get_opt_name with the difference that the
66  * delimiter is fixed to be comma which starts a new option. To specify an
67  * option value that contains commas, double each comma.
68  */
69 const char *get_opt_value(char *buf, int buf_size, const char *p)
70 {
71     char *q;
72 
73     q = buf;
74     while (*p != '\0') {
75         if (*p == ',') {
76             if (*(p + 1) != ',')
77                 break;
78             p++;
79         }
80         if (q && (q - buf) < buf_size - 1)
81             *q++ = *p;
82         p++;
83     }
84     if (q)
85         *q = '\0';
86 
87     return p;
88 }
89 
90 int get_next_param_value(char *buf, int buf_size,
91                          const char *tag, const char **pstr)
92 {
93     const char *p;
94     char option[128];
95 
96     p = *pstr;
97     for(;;) {
98         p = get_opt_name(option, sizeof(option), p, '=');
99         if (*p != '=')
100             break;
101         p++;
102         if (!strcmp(tag, option)) {
103             *pstr = get_opt_value(buf, buf_size, p);
104             if (**pstr == ',') {
105                 (*pstr)++;
106             }
107             return strlen(buf);
108         } else {
109             p = get_opt_value(NULL, 0, p);
110         }
111         if (*p != ',')
112             break;
113         p++;
114     }
115     return 0;
116 }
117 
118 int get_param_value(char *buf, int buf_size,
119                     const char *tag, const char *str)
120 {
121     return get_next_param_value(buf, buf_size, tag, &str);
122 }
123 
124 static void parse_option_bool(const char *name, const char *value, bool *ret,
125                               Error **errp)
126 {
127     if (value != NULL) {
128         if (!strcmp(value, "on")) {
129             *ret = 1;
130         } else if (!strcmp(value, "off")) {
131             *ret = 0;
132         } else {
133             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
134                        name, "'on' or 'off'");
135         }
136     } else {
137         *ret = 1;
138     }
139 }
140 
141 static void parse_option_number(const char *name, const char *value,
142                                 uint64_t *ret, Error **errp)
143 {
144     char *postfix;
145     uint64_t number;
146 
147     if (value != NULL) {
148         number = strtoull(value, &postfix, 0);
149         if (*postfix != '\0') {
150             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
151             return;
152         }
153         *ret = number;
154     } else {
155         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
156     }
157 }
158 
159 static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
160                                             const char *name)
161 {
162     int i;
163 
164     for (i = 0; desc[i].name != NULL; i++) {
165         if (strcmp(desc[i].name, name) == 0) {
166             return &desc[i];
167         }
168     }
169 
170     return NULL;
171 }
172 
173 void parse_option_size(const char *name, const char *value,
174                        uint64_t *ret, Error **errp)
175 {
176     char *postfix;
177     double sizef;
178 
179     if (value != NULL) {
180         sizef = strtod(value, &postfix);
181         if (sizef < 0 || sizef > UINT64_MAX) {
182             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
183                              "a non-negative number below 2^64");
184             return;
185         }
186         switch (*postfix) {
187         case 'T':
188             sizef *= 1024;
189             /* fall through */
190         case 'G':
191             sizef *= 1024;
192             /* fall through */
193         case 'M':
194             sizef *= 1024;
195             /* fall through */
196         case 'K':
197         case 'k':
198             sizef *= 1024;
199             /* fall through */
200         case 'b':
201         case '\0':
202             *ret = (uint64_t) sizef;
203             break;
204         default:
205             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a size");
206             error_append_hint(errp, "You may use k, M, G or T suffixes for "
207                     "kilobytes, megabytes, gigabytes and terabytes.\n");
208             return;
209         }
210     } else {
211         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a size");
212     }
213 }
214 
215 bool has_help_option(const char *param)
216 {
217     size_t buflen = strlen(param) + 1;
218     char *buf = g_malloc(buflen);
219     const char *p = param;
220     bool result = false;
221 
222     while (*p) {
223         p = get_opt_value(buf, buflen, p);
224         if (*p) {
225             p++;
226         }
227 
228         if (is_help_option(buf)) {
229             result = true;
230             goto out;
231         }
232     }
233 
234 out:
235     g_free(buf);
236     return result;
237 }
238 
239 bool is_valid_option_list(const char *param)
240 {
241     size_t buflen = strlen(param) + 1;
242     char *buf = g_malloc(buflen);
243     const char *p = param;
244     bool result = true;
245 
246     while (*p) {
247         p = get_opt_value(buf, buflen, p);
248         if (*p && !*++p) {
249             result = false;
250             goto out;
251         }
252 
253         if (!*buf || *buf == ',') {
254             result = false;
255             goto out;
256         }
257     }
258 
259 out:
260     g_free(buf);
261     return result;
262 }
263 
264 void qemu_opts_print_help(QemuOptsList *list)
265 {
266     QemuOptDesc *desc;
267 
268     assert(list);
269     desc = list->desc;
270     printf("Supported options:\n");
271     while (desc && desc->name) {
272         printf("%-16s %s\n", desc->name,
273                desc->help ? desc->help : "No description available");
274         desc++;
275     }
276 }
277 /* ------------------------------------------------------------------ */
278 
279 QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
280 {
281     QemuOpt *opt;
282 
283     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
284         if (strcmp(opt->name, name) != 0)
285             continue;
286         return opt;
287     }
288     return NULL;
289 }
290 
291 static void qemu_opt_del(QemuOpt *opt)
292 {
293     QTAILQ_REMOVE(&opt->opts->head, opt, next);
294     g_free(opt->name);
295     g_free(opt->str);
296     g_free(opt);
297 }
298 
299 /* qemu_opt_set allows many settings for the same option.
300  * This function deletes all settings for an option.
301  */
302 static void qemu_opt_del_all(QemuOpts *opts, const char *name)
303 {
304     QemuOpt *opt, *next_opt;
305 
306     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next_opt) {
307         if (!strcmp(opt->name, name)) {
308             qemu_opt_del(opt);
309         }
310     }
311 }
312 
313 const char *qemu_opt_get(QemuOpts *opts, const char *name)
314 {
315     QemuOpt *opt;
316 
317     if (opts == NULL) {
318         return NULL;
319     }
320 
321     opt = qemu_opt_find(opts, name);
322     if (!opt) {
323         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
324         if (desc && desc->def_value_str) {
325             return desc->def_value_str;
326         }
327     }
328     return opt ? opt->str : NULL;
329 }
330 
331 /* Get a known option (or its default) and remove it from the list
332  * all in one action. Return a malloced string of the option value.
333  * Result must be freed by caller with g_free().
334  */
335 char *qemu_opt_get_del(QemuOpts *opts, const char *name)
336 {
337     QemuOpt *opt;
338     const QemuOptDesc *desc;
339     char *str = NULL;
340 
341     if (opts == NULL) {
342         return NULL;
343     }
344 
345     opt = qemu_opt_find(opts, name);
346     if (!opt) {
347         desc = find_desc_by_name(opts->list->desc, name);
348         if (desc && desc->def_value_str) {
349             str = g_strdup(desc->def_value_str);
350         }
351         return str;
352     }
353     str = opt->str;
354     opt->str = NULL;
355     qemu_opt_del_all(opts, name);
356     return str;
357 }
358 
359 bool qemu_opt_has_help_opt(QemuOpts *opts)
360 {
361     QemuOpt *opt;
362 
363     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
364         if (is_help_option(opt->name)) {
365             return true;
366         }
367     }
368     return false;
369 }
370 
371 static bool qemu_opt_get_bool_helper(QemuOpts *opts, const char *name,
372                                      bool defval, bool del)
373 {
374     QemuOpt *opt;
375     bool ret = defval;
376 
377     if (opts == NULL) {
378         return ret;
379     }
380 
381     opt = qemu_opt_find(opts, name);
382     if (opt == NULL) {
383         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
384         if (desc && desc->def_value_str) {
385             parse_option_bool(name, desc->def_value_str, &ret, &error_abort);
386         }
387         return ret;
388     }
389     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
390     ret = opt->value.boolean;
391     if (del) {
392         qemu_opt_del_all(opts, name);
393     }
394     return ret;
395 }
396 
397 bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
398 {
399     return qemu_opt_get_bool_helper(opts, name, defval, false);
400 }
401 
402 bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
403 {
404     return qemu_opt_get_bool_helper(opts, name, defval, true);
405 }
406 
407 static uint64_t qemu_opt_get_number_helper(QemuOpts *opts, const char *name,
408                                            uint64_t defval, bool del)
409 {
410     QemuOpt *opt;
411     uint64_t ret = defval;
412 
413     if (opts == NULL) {
414         return ret;
415     }
416 
417     opt = qemu_opt_find(opts, name);
418     if (opt == NULL) {
419         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
420         if (desc && desc->def_value_str) {
421             parse_option_number(name, desc->def_value_str, &ret, &error_abort);
422         }
423         return ret;
424     }
425     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
426     ret = opt->value.uint;
427     if (del) {
428         qemu_opt_del_all(opts, name);
429     }
430     return ret;
431 }
432 
433 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
434 {
435     return qemu_opt_get_number_helper(opts, name, defval, false);
436 }
437 
438 uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
439                                  uint64_t defval)
440 {
441     return qemu_opt_get_number_helper(opts, name, defval, true);
442 }
443 
444 static uint64_t qemu_opt_get_size_helper(QemuOpts *opts, const char *name,
445                                          uint64_t defval, bool del)
446 {
447     QemuOpt *opt;
448     uint64_t ret = defval;
449 
450     if (opts == NULL) {
451         return ret;
452     }
453 
454     opt = qemu_opt_find(opts, name);
455     if (opt == NULL) {
456         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
457         if (desc && desc->def_value_str) {
458             parse_option_size(name, desc->def_value_str, &ret, &error_abort);
459         }
460         return ret;
461     }
462     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
463     ret = opt->value.uint;
464     if (del) {
465         qemu_opt_del_all(opts, name);
466     }
467     return ret;
468 }
469 
470 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
471 {
472     return qemu_opt_get_size_helper(opts, name, defval, false);
473 }
474 
475 uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
476                                uint64_t defval)
477 {
478     return qemu_opt_get_size_helper(opts, name, defval, true);
479 }
480 
481 static void qemu_opt_parse(QemuOpt *opt, Error **errp)
482 {
483     if (opt->desc == NULL)
484         return;
485 
486     switch (opt->desc->type) {
487     case QEMU_OPT_STRING:
488         /* nothing */
489         return;
490     case QEMU_OPT_BOOL:
491         parse_option_bool(opt->name, opt->str, &opt->value.boolean, errp);
492         break;
493     case QEMU_OPT_NUMBER:
494         parse_option_number(opt->name, opt->str, &opt->value.uint, errp);
495         break;
496     case QEMU_OPT_SIZE:
497         parse_option_size(opt->name, opt->str, &opt->value.uint, errp);
498         break;
499     default:
500         abort();
501     }
502 }
503 
504 static bool opts_accepts_any(const QemuOpts *opts)
505 {
506     return opts->list->desc[0].name == NULL;
507 }
508 
509 int qemu_opt_unset(QemuOpts *opts, const char *name)
510 {
511     QemuOpt *opt = qemu_opt_find(opts, name);
512 
513     assert(opts_accepts_any(opts));
514 
515     if (opt == NULL) {
516         return -1;
517     } else {
518         qemu_opt_del(opt);
519         return 0;
520     }
521 }
522 
523 static void opt_set(QemuOpts *opts, const char *name, const char *value,
524                     bool prepend, Error **errp)
525 {
526     QemuOpt *opt;
527     const QemuOptDesc *desc;
528     Error *local_err = NULL;
529 
530     desc = find_desc_by_name(opts->list->desc, name);
531     if (!desc && !opts_accepts_any(opts)) {
532         error_setg(errp, QERR_INVALID_PARAMETER, name);
533         return;
534     }
535 
536     opt = g_malloc0(sizeof(*opt));
537     opt->name = g_strdup(name);
538     opt->opts = opts;
539     if (prepend) {
540         QTAILQ_INSERT_HEAD(&opts->head, opt, next);
541     } else {
542         QTAILQ_INSERT_TAIL(&opts->head, opt, next);
543     }
544     opt->desc = desc;
545     opt->str = g_strdup(value);
546     qemu_opt_parse(opt, &local_err);
547     if (local_err) {
548         error_propagate(errp, local_err);
549         qemu_opt_del(opt);
550     }
551 }
552 
553 void qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
554                   Error **errp)
555 {
556     opt_set(opts, name, value, false, errp);
557 }
558 
559 void qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
560                        Error **errp)
561 {
562     QemuOpt *opt;
563     const QemuOptDesc *desc = opts->list->desc;
564 
565     opt = g_malloc0(sizeof(*opt));
566     opt->desc = find_desc_by_name(desc, name);
567     if (!opt->desc && !opts_accepts_any(opts)) {
568         error_setg(errp, QERR_INVALID_PARAMETER, name);
569         g_free(opt);
570         return;
571     }
572 
573     opt->name = g_strdup(name);
574     opt->opts = opts;
575     opt->value.boolean = !!val;
576     opt->str = g_strdup(val ? "on" : "off");
577     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
578 }
579 
580 void qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
581                          Error **errp)
582 {
583     QemuOpt *opt;
584     const QemuOptDesc *desc = opts->list->desc;
585 
586     opt = g_malloc0(sizeof(*opt));
587     opt->desc = find_desc_by_name(desc, name);
588     if (!opt->desc && !opts_accepts_any(opts)) {
589         error_setg(errp, QERR_INVALID_PARAMETER, name);
590         g_free(opt);
591         return;
592     }
593 
594     opt->name = g_strdup(name);
595     opt->opts = opts;
596     opt->value.uint = val;
597     opt->str = g_strdup_printf("%" PRId64, val);
598     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
599 }
600 
601 /**
602  * For each member of @opts, call @func(@opaque, name, value, @errp).
603  * @func() may store an Error through @errp, but must return non-zero then.
604  * When @func() returns non-zero, break the loop and return that value.
605  * Return zero when the loop completes.
606  */
607 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
608                      Error **errp)
609 {
610     QemuOpt *opt;
611     int rc;
612 
613     QTAILQ_FOREACH(opt, &opts->head, next) {
614         rc = func(opaque, opt->name, opt->str, errp);
615         if (rc) {
616             return rc;
617         }
618         assert(!errp || !*errp);
619     }
620     return 0;
621 }
622 
623 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
624 {
625     QemuOpts *opts;
626 
627     QTAILQ_FOREACH(opts, &list->head, next) {
628         if (!opts->id && !id) {
629             return opts;
630         }
631         if (opts->id && id && !strcmp(opts->id, id)) {
632             return opts;
633         }
634     }
635     return NULL;
636 }
637 
638 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
639                            int fail_if_exists, Error **errp)
640 {
641     QemuOpts *opts = NULL;
642 
643     if (id) {
644         if (!id_wellformed(id)) {
645             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
646                        "an identifier");
647             error_append_hint(errp, "Identifiers consist of letters, digits, "
648                               "'-', '.', '_', starting with a letter.\n");
649             return NULL;
650         }
651         opts = qemu_opts_find(list, id);
652         if (opts != NULL) {
653             if (fail_if_exists && !list->merge_lists) {
654                 error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
655                 return NULL;
656             } else {
657                 return opts;
658             }
659         }
660     } else if (list->merge_lists) {
661         opts = qemu_opts_find(list, NULL);
662         if (opts) {
663             return opts;
664         }
665     }
666     opts = g_malloc0(sizeof(*opts));
667     opts->id = g_strdup(id);
668     opts->list = list;
669     loc_save(&opts->loc);
670     QTAILQ_INIT(&opts->head);
671     QTAILQ_INSERT_TAIL(&list->head, opts, next);
672     return opts;
673 }
674 
675 void qemu_opts_reset(QemuOptsList *list)
676 {
677     QemuOpts *opts, *next_opts;
678 
679     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
680         qemu_opts_del(opts);
681     }
682 }
683 
684 void qemu_opts_loc_restore(QemuOpts *opts)
685 {
686     loc_restore(&opts->loc);
687 }
688 
689 void qemu_opts_set(QemuOptsList *list, const char *id,
690                    const char *name, const char *value, Error **errp)
691 {
692     QemuOpts *opts;
693     Error *local_err = NULL;
694 
695     opts = qemu_opts_create(list, id, 1, &local_err);
696     if (local_err) {
697         error_propagate(errp, local_err);
698         return;
699     }
700     qemu_opt_set(opts, name, value, errp);
701 }
702 
703 const char *qemu_opts_id(QemuOpts *opts)
704 {
705     return opts->id;
706 }
707 
708 /* The id string will be g_free()d by qemu_opts_del */
709 void qemu_opts_set_id(QemuOpts *opts, char *id)
710 {
711     opts->id = id;
712 }
713 
714 void qemu_opts_del(QemuOpts *opts)
715 {
716     QemuOpt *opt;
717 
718     if (opts == NULL) {
719         return;
720     }
721 
722     for (;;) {
723         opt = QTAILQ_FIRST(&opts->head);
724         if (opt == NULL)
725             break;
726         qemu_opt_del(opt);
727     }
728     QTAILQ_REMOVE(&opts->list->head, opts, next);
729     g_free(opts->id);
730     g_free(opts);
731 }
732 
733 /* print value, escaping any commas in value */
734 static void escaped_print(const char *value)
735 {
736     const char *ptr;
737 
738     for (ptr = value; *ptr; ++ptr) {
739         if (*ptr == ',') {
740             putchar(',');
741         }
742         putchar(*ptr);
743     }
744 }
745 
746 void qemu_opts_print(QemuOpts *opts, const char *separator)
747 {
748     QemuOpt *opt;
749     QemuOptDesc *desc = opts->list->desc;
750     const char *sep = "";
751 
752     if (opts->id) {
753         printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
754         sep = separator;
755     }
756 
757     if (desc[0].name == NULL) {
758         QTAILQ_FOREACH(opt, &opts->head, next) {
759             printf("%s%s=", sep, opt->name);
760             escaped_print(opt->str);
761             sep = separator;
762         }
763         return;
764     }
765     for (; desc && desc->name; desc++) {
766         const char *value;
767         QemuOpt *opt = qemu_opt_find(opts, desc->name);
768 
769         value = opt ? opt->str : desc->def_value_str;
770         if (!value) {
771             continue;
772         }
773         if (desc->type == QEMU_OPT_STRING) {
774             printf("%s%s=", sep, desc->name);
775             escaped_print(value);
776         } else if ((desc->type == QEMU_OPT_SIZE ||
777                     desc->type == QEMU_OPT_NUMBER) && opt) {
778             printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
779         } else {
780             printf("%s%s=%s", sep, desc->name, value);
781         }
782         sep = separator;
783     }
784 }
785 
786 static void opts_do_parse(QemuOpts *opts, const char *params,
787                           const char *firstname, bool prepend, Error **errp)
788 {
789     char option[128], value[1024];
790     const char *p,*pe,*pc;
791     Error *local_err = NULL;
792 
793     for (p = params; *p != '\0'; p++) {
794         pe = strchr(p, '=');
795         pc = strchr(p, ',');
796         if (!pe || (pc && pc < pe)) {
797             /* found "foo,more" */
798             if (p == params && firstname) {
799                 /* implicitly named first option */
800                 pstrcpy(option, sizeof(option), firstname);
801                 p = get_opt_value(value, sizeof(value), p);
802             } else {
803                 /* option without value, probably a flag */
804                 p = get_opt_name(option, sizeof(option), p, ',');
805                 if (strncmp(option, "no", 2) == 0) {
806                     memmove(option, option+2, strlen(option+2)+1);
807                     pstrcpy(value, sizeof(value), "off");
808                 } else {
809                     pstrcpy(value, sizeof(value), "on");
810                 }
811             }
812         } else {
813             /* found "foo=bar,more" */
814             p = get_opt_name(option, sizeof(option), p, '=');
815             if (*p != '=') {
816                 break;
817             }
818             p++;
819             p = get_opt_value(value, sizeof(value), p);
820         }
821         if (strcmp(option, "id") != 0) {
822             /* store and parse */
823             opt_set(opts, option, value, prepend, &local_err);
824             if (local_err) {
825                 error_propagate(errp, local_err);
826                 return;
827             }
828         }
829         if (*p != ',') {
830             break;
831         }
832     }
833 }
834 
835 /**
836  * Store options parsed from @params into @opts.
837  * If @firstname is non-null, the first key=value in @params may omit
838  * key=, and is treated as if key was @firstname.
839  * On error, store an error object through @errp if non-null.
840  */
841 void qemu_opts_do_parse(QemuOpts *opts, const char *params,
842                        const char *firstname, Error **errp)
843 {
844     opts_do_parse(opts, params, firstname, false, errp);
845 }
846 
847 static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
848                             bool permit_abbrev, bool defaults, Error **errp)
849 {
850     const char *firstname;
851     char value[1024], *id = NULL;
852     const char *p;
853     QemuOpts *opts;
854     Error *local_err = NULL;
855 
856     assert(!permit_abbrev || list->implied_opt_name);
857     firstname = permit_abbrev ? list->implied_opt_name : NULL;
858 
859     if (strncmp(params, "id=", 3) == 0) {
860         get_opt_value(value, sizeof(value), params+3);
861         id = value;
862     } else if ((p = strstr(params, ",id=")) != NULL) {
863         get_opt_value(value, sizeof(value), p+4);
864         id = value;
865     }
866 
867     /*
868      * This code doesn't work for defaults && !list->merge_lists: when
869      * params has no id=, and list has an element with !opts->id, it
870      * appends a new element instead of returning the existing opts.
871      * However, we got no use for this case.  Guard against possible
872      * (if unlikely) future misuse:
873      */
874     assert(!defaults || list->merge_lists);
875     opts = qemu_opts_create(list, id, !defaults, &local_err);
876     if (opts == NULL) {
877         error_propagate(errp, local_err);
878         return NULL;
879     }
880 
881     opts_do_parse(opts, params, firstname, defaults, &local_err);
882     if (local_err) {
883         error_propagate(errp, local_err);
884         qemu_opts_del(opts);
885         return NULL;
886     }
887 
888     return opts;
889 }
890 
891 /**
892  * Create a QemuOpts in @list and with options parsed from @params.
893  * If @permit_abbrev, the first key=value in @params may omit key=,
894  * and is treated as if key was @list->implied_opt_name.
895  * On error, store an error object through @errp if non-null.
896  * Return the new QemuOpts on success, null pointer on error.
897  */
898 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
899                           bool permit_abbrev, Error **errp)
900 {
901     return opts_parse(list, params, permit_abbrev, false, errp);
902 }
903 
904 /**
905  * Create a QemuOpts in @list and with options parsed from @params.
906  * If @permit_abbrev, the first key=value in @params may omit key=,
907  * and is treated as if key was @list->implied_opt_name.
908  * Report errors with error_report_err().  This is inappropriate in
909  * QMP context.  Do not use this function there!
910  * Return the new QemuOpts on success, null pointer on error.
911  */
912 QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
913                                   bool permit_abbrev)
914 {
915     Error *err = NULL;
916     QemuOpts *opts;
917 
918     opts = opts_parse(list, params, permit_abbrev, false, &err);
919     if (err) {
920         error_report_err(err);
921     }
922     return opts;
923 }
924 
925 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,
926                             int permit_abbrev)
927 {
928     QemuOpts *opts;
929 
930     opts = opts_parse(list, params, permit_abbrev, true, NULL);
931     assert(opts);
932 }
933 
934 typedef struct OptsFromQDictState {
935     QemuOpts *opts;
936     Error **errp;
937 } OptsFromQDictState;
938 
939 static void qemu_opts_from_qdict_1(const char *key, QObject *obj, void *opaque)
940 {
941     OptsFromQDictState *state = opaque;
942     char buf[32];
943     const char *value;
944     int n;
945 
946     if (!strcmp(key, "id") || *state->errp) {
947         return;
948     }
949 
950     switch (qobject_type(obj)) {
951     case QTYPE_QSTRING:
952         value = qstring_get_str(qobject_to_qstring(obj));
953         break;
954     case QTYPE_QINT:
955         n = snprintf(buf, sizeof(buf), "%" PRId64,
956                      qint_get_int(qobject_to_qint(obj)));
957         assert(n < sizeof(buf));
958         value = buf;
959         break;
960     case QTYPE_QFLOAT:
961         n = snprintf(buf, sizeof(buf), "%.17g",
962                      qfloat_get_double(qobject_to_qfloat(obj)));
963         assert(n < sizeof(buf));
964         value = buf;
965         break;
966     case QTYPE_QBOOL:
967         pstrcpy(buf, sizeof(buf),
968                 qbool_get_bool(qobject_to_qbool(obj)) ? "on" : "off");
969         value = buf;
970         break;
971     default:
972         return;
973     }
974 
975     qemu_opt_set(state->opts, key, value, state->errp);
976 }
977 
978 /*
979  * Create QemuOpts from a QDict.
980  * Use value of key "id" as ID if it exists and is a QString.
981  * Only QStrings, QInts, QFloats and QBools are copied.  Entries with
982  * other types are silently ignored.
983  */
984 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
985                                Error **errp)
986 {
987     OptsFromQDictState state;
988     Error *local_err = NULL;
989     QemuOpts *opts;
990 
991     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1,
992                             &local_err);
993     if (local_err) {
994         error_propagate(errp, local_err);
995         return NULL;
996     }
997 
998     assert(opts != NULL);
999 
1000     state.errp = &local_err;
1001     state.opts = opts;
1002     qdict_iter(qdict, qemu_opts_from_qdict_1, &state);
1003     if (local_err) {
1004         error_propagate(errp, local_err);
1005         qemu_opts_del(opts);
1006         return NULL;
1007     }
1008 
1009     return opts;
1010 }
1011 
1012 /*
1013  * Adds all QDict entries to the QemuOpts that can be added and removes them
1014  * from the QDict. When this function returns, the QDict contains only those
1015  * entries that couldn't be added to the QemuOpts.
1016  */
1017 void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
1018 {
1019     const QDictEntry *entry, *next;
1020 
1021     entry = qdict_first(qdict);
1022 
1023     while (entry != NULL) {
1024         Error *local_err = NULL;
1025         OptsFromQDictState state = {
1026             .errp = &local_err,
1027             .opts = opts,
1028         };
1029 
1030         next = qdict_next(qdict, entry);
1031 
1032         if (find_desc_by_name(opts->list->desc, entry->key)) {
1033             qemu_opts_from_qdict_1(entry->key, entry->value, &state);
1034             if (local_err) {
1035                 error_propagate(errp, local_err);
1036                 return;
1037             } else {
1038                 qdict_del(qdict, entry->key);
1039             }
1040         }
1041 
1042         entry = next;
1043     }
1044 }
1045 
1046 /*
1047  * Convert from QemuOpts to QDict.
1048  * The QDict values are of type QString.
1049  * TODO We'll want to use types appropriate for opt->desc->type, but
1050  * this is enough for now.
1051  */
1052 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
1053 {
1054     QemuOpt *opt;
1055     QObject *val;
1056 
1057     if (!qdict) {
1058         qdict = qdict_new();
1059     }
1060     if (opts->id) {
1061         qdict_put(qdict, "id", qstring_from_str(opts->id));
1062     }
1063     QTAILQ_FOREACH(opt, &opts->head, next) {
1064         val = QOBJECT(qstring_from_str(opt->str));
1065         qdict_put_obj(qdict, opt->name, val);
1066     }
1067     return qdict;
1068 }
1069 
1070 /* Validate parsed opts against descriptions where no
1071  * descriptions were provided in the QemuOptsList.
1072  */
1073 void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
1074 {
1075     QemuOpt *opt;
1076     Error *local_err = NULL;
1077 
1078     assert(opts_accepts_any(opts));
1079 
1080     QTAILQ_FOREACH(opt, &opts->head, next) {
1081         opt->desc = find_desc_by_name(desc, opt->name);
1082         if (!opt->desc) {
1083             error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
1084             return;
1085         }
1086 
1087         qemu_opt_parse(opt, &local_err);
1088         if (local_err) {
1089             error_propagate(errp, local_err);
1090             return;
1091         }
1092     }
1093 }
1094 
1095 /**
1096  * For each member of @list, call @func(@opaque, member, @errp).
1097  * Call it with the current location temporarily set to the member's.
1098  * @func() may store an Error through @errp, but must return non-zero then.
1099  * When @func() returns non-zero, break the loop and return that value.
1100  * Return zero when the loop completes.
1101  */
1102 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
1103                       void *opaque, Error **errp)
1104 {
1105     Location loc;
1106     QemuOpts *opts;
1107     int rc;
1108 
1109     loc_push_none(&loc);
1110     QTAILQ_FOREACH(opts, &list->head, next) {
1111         loc_restore(&opts->loc);
1112         rc = func(opaque, opts, errp);
1113         if (rc) {
1114             return rc;
1115         }
1116         assert(!errp || !*errp);
1117     }
1118     loc_pop(&loc);
1119     return 0;
1120 }
1121 
1122 static size_t count_opts_list(QemuOptsList *list)
1123 {
1124     QemuOptDesc *desc = NULL;
1125     size_t num_opts = 0;
1126 
1127     if (!list) {
1128         return 0;
1129     }
1130 
1131     desc = list->desc;
1132     while (desc && desc->name) {
1133         num_opts++;
1134         desc++;
1135     }
1136 
1137     return num_opts;
1138 }
1139 
1140 void qemu_opts_free(QemuOptsList *list)
1141 {
1142     g_free(list);
1143 }
1144 
1145 /* Realloc dst option list and append options from an option list (list)
1146  * to it. dst could be NULL or a malloced list.
1147  * The lifetime of dst must be shorter than the input list because the
1148  * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
1149  */
1150 QemuOptsList *qemu_opts_append(QemuOptsList *dst,
1151                                QemuOptsList *list)
1152 {
1153     size_t num_opts, num_dst_opts;
1154     QemuOptDesc *desc;
1155     bool need_init = false;
1156     bool need_head_update;
1157 
1158     if (!list) {
1159         return dst;
1160     }
1161 
1162     /* If dst is NULL, after realloc, some area of dst should be initialized
1163      * before adding options to it.
1164      */
1165     if (!dst) {
1166         need_init = true;
1167         need_head_update = true;
1168     } else {
1169         /* Moreover, even if dst is not NULL, the realloc may move it to a
1170          * different address in which case we may get a stale tail pointer
1171          * in dst->head. */
1172         need_head_update = QTAILQ_EMPTY(&dst->head);
1173     }
1174 
1175     num_opts = count_opts_list(dst);
1176     num_dst_opts = num_opts;
1177     num_opts += count_opts_list(list);
1178     dst = g_realloc(dst, sizeof(QemuOptsList) +
1179                     (num_opts + 1) * sizeof(QemuOptDesc));
1180     if (need_init) {
1181         dst->name = NULL;
1182         dst->implied_opt_name = NULL;
1183         dst->merge_lists = false;
1184     }
1185     if (need_head_update) {
1186         QTAILQ_INIT(&dst->head);
1187     }
1188     dst->desc[num_dst_opts].name = NULL;
1189 
1190     /* append list->desc to dst->desc */
1191     if (list) {
1192         desc = list->desc;
1193         while (desc && desc->name) {
1194             if (find_desc_by_name(dst->desc, desc->name) == NULL) {
1195                 dst->desc[num_dst_opts++] = *desc;
1196                 dst->desc[num_dst_opts].name = NULL;
1197             }
1198             desc++;
1199         }
1200     }
1201 
1202     return dst;
1203 }
1204