xref: /openbmc/qemu/util/qemu-option.c (revision 4a4ff4c5)
1 /*
2  * Commandline option parsing functions
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2009 Kevin Wolf <kwolf@redhat.com>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 
28 #include "qapi/error.h"
29 #include "qemu-common.h"
30 #include "qemu/error-report.h"
31 #include "qapi/qmp/qbool.h"
32 #include "qapi/qmp/qdict.h"
33 #include "qapi/qmp/qnum.h"
34 #include "qapi/qmp/qstring.h"
35 #include "qapi/qmp/qerror.h"
36 #include "qemu/option_int.h"
37 #include "qemu/cutils.h"
38 #include "qemu/id.h"
39 #include "qemu/help_option.h"
40 
41 /*
42  * Extracts the name of an option from the parameter string (p points at the
43  * first byte of the option name)
44  *
45  * The option name is delimited by delim (usually , or =) or the string end
46  * and is copied into option. The caller is responsible for free'ing option
47  * when no longer required.
48  *
49  * The return value is the position of the delimiter/zero byte after the option
50  * name in p.
51  */
52 static const char *get_opt_name(const char *p, char **option, char delim)
53 {
54     char *offset = strchr(p, delim);
55 
56     if (offset) {
57         *option = g_strndup(p, offset - p);
58         return offset;
59     } else {
60         *option = g_strdup(p);
61         return p + strlen(p);
62     }
63 }
64 
65 /*
66  * Extracts the value of an option from the parameter string p (p points at the
67  * first byte of the option value)
68  *
69  * This function is comparable to get_opt_name with the difference that the
70  * delimiter is fixed to be comma which starts a new option. To specify an
71  * option value that contains commas, double each comma.
72  */
73 const char *get_opt_value(const char *p, char **value)
74 {
75     size_t capacity = 0, length;
76     const char *offset;
77 
78     *value = NULL;
79     while (1) {
80         offset = strchr(p, ',');
81         if (!offset) {
82             offset = p + strlen(p);
83         }
84 
85         length = offset - p;
86         if (*offset != '\0' && *(offset + 1) == ',') {
87             length++;
88         }
89         if (value) {
90             *value = g_renew(char, *value, capacity + length + 1);
91             strncpy(*value + capacity, p, length);
92             (*value)[capacity + length] = '\0';
93         }
94         capacity += length;
95         if (*offset == '\0' ||
96             *(offset + 1) != ',') {
97             break;
98         }
99 
100         p += (offset - p) + 2;
101     }
102 
103     return offset;
104 }
105 
106 static void parse_option_bool(const char *name, const char *value, bool *ret,
107                               Error **errp)
108 {
109     if (!strcmp(value, "on")) {
110         *ret = 1;
111     } else if (!strcmp(value, "off")) {
112         *ret = 0;
113     } else {
114         error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
115                    name, "'on' or 'off'");
116     }
117 }
118 
119 static void parse_option_number(const char *name, const char *value,
120                                 uint64_t *ret, Error **errp)
121 {
122     uint64_t number;
123     int err;
124 
125     err = qemu_strtou64(value, NULL, 0, &number);
126     if (err == -ERANGE) {
127         error_setg(errp, "Value '%s' is too large for parameter '%s'",
128                    value, name);
129         return;
130     }
131     if (err) {
132         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name, "a number");
133         return;
134     }
135     *ret = number;
136 }
137 
138 static const QemuOptDesc *find_desc_by_name(const QemuOptDesc *desc,
139                                             const char *name)
140 {
141     int i;
142 
143     for (i = 0; desc[i].name != NULL; i++) {
144         if (strcmp(desc[i].name, name) == 0) {
145             return &desc[i];
146         }
147     }
148 
149     return NULL;
150 }
151 
152 void parse_option_size(const char *name, const char *value,
153                        uint64_t *ret, Error **errp)
154 {
155     uint64_t size;
156     int err;
157 
158     err = qemu_strtosz(value, NULL, &size);
159     if (err == -ERANGE) {
160         error_setg(errp, "Value '%s' is out of range for parameter '%s'",
161                    value, name);
162         return;
163     }
164     if (err) {
165         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
166                    "a non-negative number below 2^64");
167         error_append_hint(errp, "Optional suffix k, M, G, T, P or E means"
168                           " kilo-, mega-, giga-, tera-, peta-\n"
169                           "and exabytes, respectively.\n");
170         return;
171     }
172     *ret = size;
173 }
174 
175 bool has_help_option(const char *param)
176 {
177     const char *p = param;
178     bool result = false;
179 
180     while (*p && !result) {
181         char *value;
182 
183         p = get_opt_value(p, &value);
184         if (*p) {
185             p++;
186         }
187 
188         result = is_help_option(value);
189         g_free(value);
190     }
191 
192     return result;
193 }
194 
195 bool is_valid_option_list(const char *p)
196 {
197     char *value = NULL;
198     bool result = false;
199 
200     while (*p) {
201         p = get_opt_value(p, &value);
202         if ((*p && !*++p) ||
203             (!*value || *value == ',')) {
204             goto out;
205         }
206 
207         g_free(value);
208         value = NULL;
209     }
210 
211     result = true;
212 out:
213     g_free(value);
214     return result;
215 }
216 
217 void qemu_opts_print_help(QemuOptsList *list)
218 {
219     QemuOptDesc *desc;
220 
221     assert(list);
222     desc = list->desc;
223     printf("Supported options:\n");
224     while (desc && desc->name) {
225         printf("%-16s %s\n", desc->name,
226                desc->help ? desc->help : "No description available");
227         desc++;
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, QemuOptHead, 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         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
277         if (desc && desc->def_value_str) {
278             return desc->def_value_str;
279         }
280     }
281     return opt ? opt->str : NULL;
282 }
283 
284 void qemu_opt_iter_init(QemuOptsIter *iter, QemuOpts *opts, const char *name)
285 {
286     iter->opts = opts;
287     iter->opt = QTAILQ_FIRST(&opts->head);
288     iter->name = name;
289 }
290 
291 const char *qemu_opt_iter_next(QemuOptsIter *iter)
292 {
293     QemuOpt *ret = iter->opt;
294     if (iter->name) {
295         while (ret && !g_str_equal(iter->name, ret->name)) {
296             ret = QTAILQ_NEXT(ret, next);
297         }
298     }
299     iter->opt = ret ? QTAILQ_NEXT(ret, next) : NULL;
300     return ret ? ret->str : NULL;
301 }
302 
303 /* Get a known option (or its default) and remove it from the list
304  * all in one action. Return a malloced string of the option value.
305  * Result must be freed by caller with g_free().
306  */
307 char *qemu_opt_get_del(QemuOpts *opts, const char *name)
308 {
309     QemuOpt *opt;
310     const QemuOptDesc *desc;
311     char *str = NULL;
312 
313     if (opts == NULL) {
314         return NULL;
315     }
316 
317     opt = qemu_opt_find(opts, name);
318     if (!opt) {
319         desc = find_desc_by_name(opts->list->desc, name);
320         if (desc && desc->def_value_str) {
321             str = g_strdup(desc->def_value_str);
322         }
323         return str;
324     }
325     str = opt->str;
326     opt->str = NULL;
327     qemu_opt_del_all(opts, name);
328     return str;
329 }
330 
331 bool qemu_opt_has_help_opt(QemuOpts *opts)
332 {
333     QemuOpt *opt;
334 
335     QTAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
336         if (is_help_option(opt->name)) {
337             return true;
338         }
339     }
340     return false;
341 }
342 
343 static bool qemu_opt_get_bool_helper(QemuOpts *opts, const char *name,
344                                      bool defval, bool del)
345 {
346     QemuOpt *opt;
347     bool ret = defval;
348 
349     if (opts == NULL) {
350         return ret;
351     }
352 
353     opt = qemu_opt_find(opts, name);
354     if (opt == NULL) {
355         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
356         if (desc && desc->def_value_str) {
357             parse_option_bool(name, desc->def_value_str, &ret, &error_abort);
358         }
359         return ret;
360     }
361     assert(opt->desc && opt->desc->type == QEMU_OPT_BOOL);
362     ret = opt->value.boolean;
363     if (del) {
364         qemu_opt_del_all(opts, name);
365     }
366     return ret;
367 }
368 
369 bool qemu_opt_get_bool(QemuOpts *opts, const char *name, bool defval)
370 {
371     return qemu_opt_get_bool_helper(opts, name, defval, false);
372 }
373 
374 bool qemu_opt_get_bool_del(QemuOpts *opts, const char *name, bool defval)
375 {
376     return qemu_opt_get_bool_helper(opts, name, defval, true);
377 }
378 
379 static uint64_t qemu_opt_get_number_helper(QemuOpts *opts, const char *name,
380                                            uint64_t defval, bool del)
381 {
382     QemuOpt *opt;
383     uint64_t ret = defval;
384 
385     if (opts == NULL) {
386         return ret;
387     }
388 
389     opt = qemu_opt_find(opts, name);
390     if (opt == NULL) {
391         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
392         if (desc && desc->def_value_str) {
393             parse_option_number(name, desc->def_value_str, &ret, &error_abort);
394         }
395         return ret;
396     }
397     assert(opt->desc && opt->desc->type == QEMU_OPT_NUMBER);
398     ret = opt->value.uint;
399     if (del) {
400         qemu_opt_del_all(opts, name);
401     }
402     return ret;
403 }
404 
405 uint64_t qemu_opt_get_number(QemuOpts *opts, const char *name, uint64_t defval)
406 {
407     return qemu_opt_get_number_helper(opts, name, defval, false);
408 }
409 
410 uint64_t qemu_opt_get_number_del(QemuOpts *opts, const char *name,
411                                  uint64_t defval)
412 {
413     return qemu_opt_get_number_helper(opts, name, defval, true);
414 }
415 
416 static uint64_t qemu_opt_get_size_helper(QemuOpts *opts, const char *name,
417                                          uint64_t defval, bool del)
418 {
419     QemuOpt *opt;
420     uint64_t ret = defval;
421 
422     if (opts == NULL) {
423         return ret;
424     }
425 
426     opt = qemu_opt_find(opts, name);
427     if (opt == NULL) {
428         const QemuOptDesc *desc = find_desc_by_name(opts->list->desc, name);
429         if (desc && desc->def_value_str) {
430             parse_option_size(name, desc->def_value_str, &ret, &error_abort);
431         }
432         return ret;
433     }
434     assert(opt->desc && opt->desc->type == QEMU_OPT_SIZE);
435     ret = opt->value.uint;
436     if (del) {
437         qemu_opt_del_all(opts, name);
438     }
439     return ret;
440 }
441 
442 uint64_t qemu_opt_get_size(QemuOpts *opts, const char *name, uint64_t defval)
443 {
444     return qemu_opt_get_size_helper(opts, name, defval, false);
445 }
446 
447 uint64_t qemu_opt_get_size_del(QemuOpts *opts, const char *name,
448                                uint64_t defval)
449 {
450     return qemu_opt_get_size_helper(opts, name, defval, true);
451 }
452 
453 static void qemu_opt_parse(QemuOpt *opt, Error **errp)
454 {
455     if (opt->desc == NULL)
456         return;
457 
458     switch (opt->desc->type) {
459     case QEMU_OPT_STRING:
460         /* nothing */
461         return;
462     case QEMU_OPT_BOOL:
463         parse_option_bool(opt->name, opt->str, &opt->value.boolean, errp);
464         break;
465     case QEMU_OPT_NUMBER:
466         parse_option_number(opt->name, opt->str, &opt->value.uint, errp);
467         break;
468     case QEMU_OPT_SIZE:
469         parse_option_size(opt->name, opt->str, &opt->value.uint, errp);
470         break;
471     default:
472         abort();
473     }
474 }
475 
476 static bool opts_accepts_any(const QemuOpts *opts)
477 {
478     return opts->list->desc[0].name == NULL;
479 }
480 
481 int qemu_opt_unset(QemuOpts *opts, const char *name)
482 {
483     QemuOpt *opt = qemu_opt_find(opts, name);
484 
485     assert(opts_accepts_any(opts));
486 
487     if (opt == NULL) {
488         return -1;
489     } else {
490         qemu_opt_del(opt);
491         return 0;
492     }
493 }
494 
495 static void opt_set(QemuOpts *opts, const char *name, char *value,
496                     bool prepend, Error **errp)
497 {
498     QemuOpt *opt;
499     const QemuOptDesc *desc;
500     Error *local_err = NULL;
501 
502     desc = find_desc_by_name(opts->list->desc, name);
503     if (!desc && !opts_accepts_any(opts)) {
504         g_free(value);
505         error_setg(errp, QERR_INVALID_PARAMETER, name);
506         return;
507     }
508 
509     opt = g_malloc0(sizeof(*opt));
510     opt->name = g_strdup(name);
511     opt->opts = opts;
512     if (prepend) {
513         QTAILQ_INSERT_HEAD(&opts->head, opt, next);
514     } else {
515         QTAILQ_INSERT_TAIL(&opts->head, opt, next);
516     }
517     opt->desc = desc;
518     opt->str = value;
519     qemu_opt_parse(opt, &local_err);
520     if (local_err) {
521         error_propagate(errp, local_err);
522         qemu_opt_del(opt);
523     }
524 }
525 
526 void qemu_opt_set(QemuOpts *opts, const char *name, const char *value,
527                   Error **errp)
528 {
529     opt_set(opts, name, g_strdup(value), false, errp);
530 }
531 
532 void qemu_opt_set_bool(QemuOpts *opts, const char *name, bool val,
533                        Error **errp)
534 {
535     QemuOpt *opt;
536     const QemuOptDesc *desc = opts->list->desc;
537 
538     opt = g_malloc0(sizeof(*opt));
539     opt->desc = find_desc_by_name(desc, name);
540     if (!opt->desc && !opts_accepts_any(opts)) {
541         error_setg(errp, QERR_INVALID_PARAMETER, name);
542         g_free(opt);
543         return;
544     }
545 
546     opt->name = g_strdup(name);
547     opt->opts = opts;
548     opt->value.boolean = !!val;
549     opt->str = g_strdup(val ? "on" : "off");
550     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
551 }
552 
553 void qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
554                          Error **errp)
555 {
556     QemuOpt *opt;
557     const QemuOptDesc *desc = opts->list->desc;
558 
559     opt = g_malloc0(sizeof(*opt));
560     opt->desc = find_desc_by_name(desc, name);
561     if (!opt->desc && !opts_accepts_any(opts)) {
562         error_setg(errp, QERR_INVALID_PARAMETER, name);
563         g_free(opt);
564         return;
565     }
566 
567     opt->name = g_strdup(name);
568     opt->opts = opts;
569     opt->value.uint = val;
570     opt->str = g_strdup_printf("%" PRId64, val);
571     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
572 }
573 
574 /**
575  * For each member of @opts, call @func(@opaque, name, value, @errp).
576  * @func() may store an Error through @errp, but must return non-zero then.
577  * When @func() returns non-zero, break the loop and return that value.
578  * Return zero when the loop completes.
579  */
580 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
581                      Error **errp)
582 {
583     QemuOpt *opt;
584     int rc;
585 
586     QTAILQ_FOREACH(opt, &opts->head, next) {
587         rc = func(opaque, opt->name, opt->str, errp);
588         if (rc) {
589             return rc;
590         }
591         assert(!errp || !*errp);
592     }
593     return 0;
594 }
595 
596 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
597 {
598     QemuOpts *opts;
599 
600     QTAILQ_FOREACH(opts, &list->head, next) {
601         if (!opts->id && !id) {
602             return opts;
603         }
604         if (opts->id && id && !strcmp(opts->id, id)) {
605             return opts;
606         }
607     }
608     return NULL;
609 }
610 
611 QemuOpts *qemu_opts_create(QemuOptsList *list, const char *id,
612                            int fail_if_exists, Error **errp)
613 {
614     QemuOpts *opts = NULL;
615 
616     if (id) {
617         if (!id_wellformed(id)) {
618             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id",
619                        "an identifier");
620             error_append_hint(errp, "Identifiers consist of letters, digits, "
621                               "'-', '.', '_', starting with a letter.\n");
622             return NULL;
623         }
624         opts = qemu_opts_find(list, id);
625         if (opts != NULL) {
626             if (fail_if_exists && !list->merge_lists) {
627                 error_setg(errp, "Duplicate ID '%s' for %s", id, list->name);
628                 return NULL;
629             } else {
630                 return opts;
631             }
632         }
633     } else if (list->merge_lists) {
634         opts = qemu_opts_find(list, NULL);
635         if (opts) {
636             return opts;
637         }
638     }
639     opts = g_malloc0(sizeof(*opts));
640     opts->id = g_strdup(id);
641     opts->list = list;
642     loc_save(&opts->loc);
643     QTAILQ_INIT(&opts->head);
644     QTAILQ_INSERT_TAIL(&list->head, opts, next);
645     return opts;
646 }
647 
648 void qemu_opts_reset(QemuOptsList *list)
649 {
650     QemuOpts *opts, *next_opts;
651 
652     QTAILQ_FOREACH_SAFE(opts, &list->head, next, next_opts) {
653         qemu_opts_del(opts);
654     }
655 }
656 
657 void qemu_opts_loc_restore(QemuOpts *opts)
658 {
659     loc_restore(&opts->loc);
660 }
661 
662 void qemu_opts_set(QemuOptsList *list, const char *id,
663                    const char *name, const char *value, Error **errp)
664 {
665     QemuOpts *opts;
666     Error *local_err = NULL;
667 
668     opts = qemu_opts_create(list, id, 1, &local_err);
669     if (local_err) {
670         error_propagate(errp, local_err);
671         return;
672     }
673     qemu_opt_set(opts, name, value, errp);
674 }
675 
676 const char *qemu_opts_id(QemuOpts *opts)
677 {
678     return opts->id;
679 }
680 
681 /* The id string will be g_free()d by qemu_opts_del */
682 void qemu_opts_set_id(QemuOpts *opts, char *id)
683 {
684     opts->id = id;
685 }
686 
687 void qemu_opts_del(QemuOpts *opts)
688 {
689     QemuOpt *opt;
690 
691     if (opts == NULL) {
692         return;
693     }
694 
695     for (;;) {
696         opt = QTAILQ_FIRST(&opts->head);
697         if (opt == NULL)
698             break;
699         qemu_opt_del(opt);
700     }
701     QTAILQ_REMOVE(&opts->list->head, opts, next);
702     g_free(opts->id);
703     g_free(opts);
704 }
705 
706 /* print value, escaping any commas in value */
707 static void escaped_print(const char *value)
708 {
709     const char *ptr;
710 
711     for (ptr = value; *ptr; ++ptr) {
712         if (*ptr == ',') {
713             putchar(',');
714         }
715         putchar(*ptr);
716     }
717 }
718 
719 void qemu_opts_print(QemuOpts *opts, const char *separator)
720 {
721     QemuOpt *opt;
722     QemuOptDesc *desc = opts->list->desc;
723     const char *sep = "";
724 
725     if (opts->id) {
726         printf("id=%s", opts->id); /* passed id_wellformed -> no commas */
727         sep = separator;
728     }
729 
730     if (desc[0].name == NULL) {
731         QTAILQ_FOREACH(opt, &opts->head, next) {
732             printf("%s%s=", sep, opt->name);
733             escaped_print(opt->str);
734             sep = separator;
735         }
736         return;
737     }
738     for (; desc && desc->name; desc++) {
739         const char *value;
740         opt = qemu_opt_find(opts, desc->name);
741 
742         value = opt ? opt->str : desc->def_value_str;
743         if (!value) {
744             continue;
745         }
746         if (desc->type == QEMU_OPT_STRING) {
747             printf("%s%s=", sep, desc->name);
748             escaped_print(value);
749         } else if ((desc->type == QEMU_OPT_SIZE ||
750                     desc->type == QEMU_OPT_NUMBER) && opt) {
751             printf("%s%s=%" PRId64, sep, desc->name, opt->value.uint);
752         } else {
753             printf("%s%s=%s", sep, desc->name, value);
754         }
755         sep = separator;
756     }
757 }
758 
759 static void opts_do_parse(QemuOpts *opts, const char *params,
760                           const char *firstname, bool prepend, Error **errp)
761 {
762     char *option = NULL;
763     char *value = NULL;
764     const char *p,*pe,*pc;
765     Error *local_err = NULL;
766 
767     for (p = params; *p != '\0'; p++) {
768         pe = strchr(p, '=');
769         pc = strchr(p, ',');
770         if (!pe || (pc && pc < pe)) {
771             /* found "foo,more" */
772             if (p == params && firstname) {
773                 /* implicitly named first option */
774                 option = g_strdup(firstname);
775                 p = get_opt_value(p, &value);
776             } else {
777                 /* option without value, probably a flag */
778                 p = get_opt_name(p, &option, ',');
779                 if (strncmp(option, "no", 2) == 0) {
780                     memmove(option, option+2, strlen(option+2)+1);
781                     value = g_strdup("off");
782                 } else {
783                     value = g_strdup("on");
784                 }
785             }
786         } else {
787             /* found "foo=bar,more" */
788             p = get_opt_name(p, &option, '=');
789             assert(*p == '=');
790             p++;
791             p = get_opt_value(p, &value);
792         }
793         if (strcmp(option, "id") != 0) {
794             /* store and parse */
795             opt_set(opts, option, value, prepend, &local_err);
796             value = NULL;
797             if (local_err) {
798                 error_propagate(errp, local_err);
799                 goto cleanup;
800             }
801         }
802         if (*p != ',') {
803             break;
804         }
805         g_free(option);
806         g_free(value);
807         option = value = NULL;
808     }
809 
810  cleanup:
811     g_free(option);
812     g_free(value);
813 }
814 
815 /**
816  * Store options parsed from @params into @opts.
817  * If @firstname is non-null, the first key=value in @params may omit
818  * key=, and is treated as if key was @firstname.
819  * On error, store an error object through @errp if non-null.
820  */
821 void qemu_opts_do_parse(QemuOpts *opts, const char *params,
822                        const char *firstname, Error **errp)
823 {
824     opts_do_parse(opts, params, firstname, false, errp);
825 }
826 
827 static QemuOpts *opts_parse(QemuOptsList *list, const char *params,
828                             bool permit_abbrev, bool defaults, Error **errp)
829 {
830     const char *firstname;
831     char *id = NULL;
832     const char *p;
833     QemuOpts *opts;
834     Error *local_err = NULL;
835 
836     assert(!permit_abbrev || list->implied_opt_name);
837     firstname = permit_abbrev ? list->implied_opt_name : NULL;
838 
839     if (strncmp(params, "id=", 3) == 0) {
840         get_opt_value(params + 3, &id);
841     } else if ((p = strstr(params, ",id=")) != NULL) {
842         get_opt_value(p + 4, &id);
843     }
844 
845     /*
846      * This code doesn't work for defaults && !list->merge_lists: when
847      * params has no id=, and list has an element with !opts->id, it
848      * appends a new element instead of returning the existing opts.
849      * However, we got no use for this case.  Guard against possible
850      * (if unlikely) future misuse:
851      */
852     assert(!defaults || list->merge_lists);
853     opts = qemu_opts_create(list, id, !defaults, &local_err);
854     g_free(id);
855     if (opts == NULL) {
856         error_propagate(errp, local_err);
857         return NULL;
858     }
859 
860     opts_do_parse(opts, params, firstname, defaults, &local_err);
861     if (local_err) {
862         error_propagate(errp, local_err);
863         qemu_opts_del(opts);
864         return NULL;
865     }
866 
867     return opts;
868 }
869 
870 /**
871  * Create a QemuOpts in @list and with options parsed from @params.
872  * If @permit_abbrev, the first key=value in @params may omit key=,
873  * and is treated as if key was @list->implied_opt_name.
874  * On error, store an error object through @errp if non-null.
875  * Return the new QemuOpts on success, null pointer on error.
876  */
877 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params,
878                           bool permit_abbrev, Error **errp)
879 {
880     return opts_parse(list, params, permit_abbrev, false, errp);
881 }
882 
883 /**
884  * Create a QemuOpts in @list and with options parsed from @params.
885  * If @permit_abbrev, the first key=value in @params may omit key=,
886  * and is treated as if key was @list->implied_opt_name.
887  * Report errors with error_report_err().  This is inappropriate in
888  * QMP context.  Do not use this function there!
889  * Return the new QemuOpts on success, null pointer on error.
890  */
891 QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params,
892                                   bool permit_abbrev)
893 {
894     Error *err = NULL;
895     QemuOpts *opts;
896 
897     opts = opts_parse(list, params, permit_abbrev, false, &err);
898     if (err) {
899         error_report_err(err);
900     }
901     return opts;
902 }
903 
904 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,
905                             int permit_abbrev)
906 {
907     QemuOpts *opts;
908 
909     opts = opts_parse(list, params, permit_abbrev, true, NULL);
910     assert(opts);
911 }
912 
913 typedef struct OptsFromQDictState {
914     QemuOpts *opts;
915     Error **errp;
916 } OptsFromQDictState;
917 
918 static void qemu_opts_from_qdict_1(const char *key, QObject *obj, void *opaque)
919 {
920     OptsFromQDictState *state = opaque;
921     char buf[32], *tmp = NULL;
922     const char *value;
923 
924     if (!strcmp(key, "id") || *state->errp) {
925         return;
926     }
927 
928     switch (qobject_type(obj)) {
929     case QTYPE_QSTRING:
930         value = qstring_get_str(qobject_to(QString, obj));
931         break;
932     case QTYPE_QNUM:
933         tmp = qnum_to_string(qobject_to(QNum, obj));
934         value = tmp;
935         break;
936     case QTYPE_QBOOL:
937         pstrcpy(buf, sizeof(buf),
938                 qbool_get_bool(qobject_to(QBool, obj)) ? "on" : "off");
939         value = buf;
940         break;
941     default:
942         return;
943     }
944 
945     qemu_opt_set(state->opts, key, value, state->errp);
946     g_free(tmp);
947 }
948 
949 /*
950  * Create QemuOpts from a QDict.
951  * Use value of key "id" as ID if it exists and is a QString.  Only
952  * QStrings, QNums and QBools are copied.  Entries with other types
953  * are silently ignored.
954  */
955 QemuOpts *qemu_opts_from_qdict(QemuOptsList *list, const QDict *qdict,
956                                Error **errp)
957 {
958     OptsFromQDictState state;
959     Error *local_err = NULL;
960     QemuOpts *opts;
961 
962     opts = qemu_opts_create(list, qdict_get_try_str(qdict, "id"), 1,
963                             &local_err);
964     if (local_err) {
965         error_propagate(errp, local_err);
966         return NULL;
967     }
968 
969     assert(opts != NULL);
970 
971     state.errp = &local_err;
972     state.opts = opts;
973     qdict_iter(qdict, qemu_opts_from_qdict_1, &state);
974     if (local_err) {
975         error_propagate(errp, local_err);
976         qemu_opts_del(opts);
977         return NULL;
978     }
979 
980     return opts;
981 }
982 
983 /*
984  * Adds all QDict entries to the QemuOpts that can be added and removes them
985  * from the QDict. When this function returns, the QDict contains only those
986  * entries that couldn't be added to the QemuOpts.
987  */
988 void qemu_opts_absorb_qdict(QemuOpts *opts, QDict *qdict, Error **errp)
989 {
990     const QDictEntry *entry, *next;
991 
992     entry = qdict_first(qdict);
993 
994     while (entry != NULL) {
995         Error *local_err = NULL;
996         OptsFromQDictState state = {
997             .errp = &local_err,
998             .opts = opts,
999         };
1000 
1001         next = qdict_next(qdict, entry);
1002 
1003         if (find_desc_by_name(opts->list->desc, entry->key)) {
1004             qemu_opts_from_qdict_1(entry->key, entry->value, &state);
1005             if (local_err) {
1006                 error_propagate(errp, local_err);
1007                 return;
1008             } else {
1009                 qdict_del(qdict, entry->key);
1010             }
1011         }
1012 
1013         entry = next;
1014     }
1015 }
1016 
1017 /*
1018  * Convert from QemuOpts to QDict. The QDict values are of type QString.
1019  *
1020  * If @list is given, only add those options to the QDict that are contained in
1021  * the list. If @del is true, any options added to the QDict are removed from
1022  * the QemuOpts, otherwise they remain there.
1023  *
1024  * If two options in @opts have the same name, they are processed in order
1025  * so that the last one wins (consistent with the reverse iteration in
1026  * qemu_opt_find()), but all of them are deleted if @del is true.
1027  *
1028  * TODO We'll want to use types appropriate for opt->desc->type, but
1029  * this is enough for now.
1030  */
1031 QDict *qemu_opts_to_qdict_filtered(QemuOpts *opts, QDict *qdict,
1032                                    QemuOptsList *list, bool del)
1033 {
1034     QemuOpt *opt, *next;
1035 
1036     if (!qdict) {
1037         qdict = qdict_new();
1038     }
1039     if (opts->id) {
1040         qdict_put_str(qdict, "id", opts->id);
1041     }
1042     QTAILQ_FOREACH_SAFE(opt, &opts->head, next, next) {
1043         if (list) {
1044             QemuOptDesc *desc;
1045             bool found = false;
1046             for (desc = list->desc; desc->name; desc++) {
1047                 if (!strcmp(desc->name, opt->name)) {
1048                     found = true;
1049                     break;
1050                 }
1051             }
1052             if (!found) {
1053                 continue;
1054             }
1055         }
1056         qdict_put_str(qdict, opt->name, opt->str);
1057         if (del) {
1058             qemu_opt_del(opt);
1059         }
1060     }
1061     return qdict;
1062 }
1063 
1064 /* Copy all options in a QemuOpts to the given QDict. See
1065  * qemu_opts_to_qdict_filtered() for details. */
1066 QDict *qemu_opts_to_qdict(QemuOpts *opts, QDict *qdict)
1067 {
1068     return qemu_opts_to_qdict_filtered(opts, qdict, NULL, false);
1069 }
1070 
1071 /* Validate parsed opts against descriptions where no
1072  * descriptions were provided in the QemuOptsList.
1073  */
1074 void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
1075 {
1076     QemuOpt *opt;
1077     Error *local_err = NULL;
1078 
1079     assert(opts_accepts_any(opts));
1080 
1081     QTAILQ_FOREACH(opt, &opts->head, next) {
1082         opt->desc = find_desc_by_name(desc, opt->name);
1083         if (!opt->desc) {
1084             error_setg(errp, QERR_INVALID_PARAMETER, opt->name);
1085             return;
1086         }
1087 
1088         qemu_opt_parse(opt, &local_err);
1089         if (local_err) {
1090             error_propagate(errp, local_err);
1091             return;
1092         }
1093     }
1094 }
1095 
1096 /**
1097  * For each member of @list, call @func(@opaque, member, @errp).
1098  * Call it with the current location temporarily set to the member's.
1099  * @func() may store an Error through @errp, but must return non-zero then.
1100  * When @func() returns non-zero, break the loop and return that value.
1101  * Return zero when the loop completes.
1102  */
1103 int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
1104                       void *opaque, Error **errp)
1105 {
1106     Location loc;
1107     QemuOpts *opts;
1108     int rc = 0;
1109 
1110     loc_push_none(&loc);
1111     QTAILQ_FOREACH(opts, &list->head, next) {
1112         loc_restore(&opts->loc);
1113         rc = func(opaque, opts, errp);
1114         if (rc) {
1115             break;
1116         }
1117         assert(!errp || !*errp);
1118     }
1119     loc_pop(&loc);
1120     return rc;
1121 }
1122 
1123 static size_t count_opts_list(QemuOptsList *list)
1124 {
1125     QemuOptDesc *desc = NULL;
1126     size_t num_opts = 0;
1127 
1128     if (!list) {
1129         return 0;
1130     }
1131 
1132     desc = list->desc;
1133     while (desc && desc->name) {
1134         num_opts++;
1135         desc++;
1136     }
1137 
1138     return num_opts;
1139 }
1140 
1141 void qemu_opts_free(QemuOptsList *list)
1142 {
1143     g_free(list);
1144 }
1145 
1146 /* Realloc dst option list and append options from an option list (list)
1147  * to it. dst could be NULL or a malloced list.
1148  * The lifetime of dst must be shorter than the input list because the
1149  * QemuOptDesc->name, ->help, and ->def_value_str strings are shared.
1150  */
1151 QemuOptsList *qemu_opts_append(QemuOptsList *dst,
1152                                QemuOptsList *list)
1153 {
1154     size_t num_opts, num_dst_opts;
1155     QemuOptDesc *desc;
1156     bool need_init = false;
1157     bool need_head_update;
1158 
1159     if (!list) {
1160         return dst;
1161     }
1162 
1163     /* If dst is NULL, after realloc, some area of dst should be initialized
1164      * before adding options to it.
1165      */
1166     if (!dst) {
1167         need_init = true;
1168         need_head_update = true;
1169     } else {
1170         /* Moreover, even if dst is not NULL, the realloc may move it to a
1171          * different address in which case we may get a stale tail pointer
1172          * in dst->head. */
1173         need_head_update = QTAILQ_EMPTY(&dst->head);
1174     }
1175 
1176     num_opts = count_opts_list(dst);
1177     num_dst_opts = num_opts;
1178     num_opts += count_opts_list(list);
1179     dst = g_realloc(dst, sizeof(QemuOptsList) +
1180                     (num_opts + 1) * sizeof(QemuOptDesc));
1181     if (need_init) {
1182         dst->name = NULL;
1183         dst->implied_opt_name = NULL;
1184         dst->merge_lists = false;
1185     }
1186     if (need_head_update) {
1187         QTAILQ_INIT(&dst->head);
1188     }
1189     dst->desc[num_dst_opts].name = NULL;
1190 
1191     /* append list->desc to dst->desc */
1192     if (list) {
1193         desc = list->desc;
1194         while (desc && desc->name) {
1195             if (find_desc_by_name(dst->desc, desc->name) == NULL) {
1196                 dst->desc[num_dst_opts++] = *desc;
1197                 dst->desc[num_dst_opts].name = NULL;
1198             }
1199             desc++;
1200         }
1201     }
1202 
1203     return dst;
1204 }
1205