Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
[qemu.git] / qapi / opts-visitor.c
1 /*
2 * Options Visitor
3 *
4 * Copyright Red Hat, Inc. 2012, 2013
5 *
6 * Author: Laszlo Ersek <lersek@redhat.com>
7 *
8 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
9 * See the COPYING.LIB file in the top-level directory.
10 *
11 */
12
13 #include "qemu-common.h"
14 #include "qapi/qmp/qerror.h"
15 #include "qapi/opts-visitor.h"
16 #include "qemu/queue.h"
17 #include "qemu/option_int.h"
18 #include "qapi/visitor-impl.h"
19
20
21 enum ListMode
22 {
23 LM_NONE, /* not traversing a list of repeated options */
24 LM_STARTED, /* opts_start_list() succeeded */
25
26 LM_IN_PROGRESS, /* opts_next_list() has been called.
27 *
28 * Generating the next list link will consume the most
29 * recently parsed QemuOpt instance of the repeated
30 * option.
31 *
32 * Parsing a value into the list link will examine the
33 * next QemuOpt instance of the repeated option, and
34 * possibly enter LM_SIGNED_INTERVAL or
35 * LM_UNSIGNED_INTERVAL.
36 */
37
38 LM_SIGNED_INTERVAL, /* opts_next_list() has been called.
39 *
40 * Generating the next list link will consume the most
41 * recently stored element from the signed interval,
42 * parsed from the most recent QemuOpt instance of the
43 * repeated option. This may consume QemuOpt itself
44 * and return to LM_IN_PROGRESS.
45 *
46 * Parsing a value into the list link will store the
47 * next element of the signed interval.
48 */
49
50 LM_UNSIGNED_INTERVAL /* Same as above, only for an unsigned interval. */
51 };
52
53 typedef enum ListMode ListMode;
54
55 struct OptsVisitor
56 {
57 Visitor visitor;
58
59 /* Ownership remains with opts_visitor_new()'s caller. */
60 const QemuOpts *opts_root;
61
62 unsigned depth;
63
64 /* Non-null iff depth is positive. Each key is a QemuOpt name. Each value
65 * is a non-empty GQueue, enumerating all QemuOpt occurrences with that
66 * name. */
67 GHashTable *unprocessed_opts;
68
69 /* The list currently being traversed with opts_start_list() /
70 * opts_next_list(). The list must have a struct element type in the
71 * schema, with a single mandatory scalar member. */
72 ListMode list_mode;
73 GQueue *repeated_opts;
74
75 /* When parsing a list of repeating options as integers, values of the form
76 * "a-b", representing a closed interval, are allowed. Elements in the
77 * range are generated individually.
78 */
79 union {
80 int64_t s;
81 uint64_t u;
82 } range_next, range_limit;
83
84 /* If "opts_root->id" is set, reinstantiate it as a fake QemuOpt for
85 * uniformity. Only its "name" and "str" fields are set. "fake_id_opt" does
86 * not survive or escape the OptsVisitor object.
87 */
88 QemuOpt *fake_id_opt;
89 };
90
91
92 static void
93 destroy_list(gpointer list)
94 {
95 g_queue_free(list);
96 }
97
98
99 static void
100 opts_visitor_insert(GHashTable *unprocessed_opts, const QemuOpt *opt)
101 {
102 GQueue *list;
103
104 list = g_hash_table_lookup(unprocessed_opts, opt->name);
105 if (list == NULL) {
106 list = g_queue_new();
107
108 /* GHashTable will never try to free the keys -- we supply NULL as
109 * "key_destroy_func" in opts_start_struct(). Thus cast away key
110 * const-ness in order to suppress gcc's warning.
111 */
112 g_hash_table_insert(unprocessed_opts, (gpointer)opt->name, list);
113 }
114
115 /* Similarly, destroy_list() doesn't call g_queue_free_full(). */
116 g_queue_push_tail(list, (gpointer)opt);
117 }
118
119
120 static void
121 opts_start_struct(Visitor *v, void **obj, const char *kind,
122 const char *name, size_t size, Error **errp)
123 {
124 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
125 const QemuOpt *opt;
126
127 if (obj) {
128 *obj = g_malloc0(size > 0 ? size : 1);
129 }
130 if (ov->depth++ > 0) {
131 return;
132 }
133
134 ov->unprocessed_opts = g_hash_table_new_full(&g_str_hash, &g_str_equal,
135 NULL, &destroy_list);
136 QTAILQ_FOREACH(opt, &ov->opts_root->head, next) {
137 /* ensured by qemu-option.c::opts_do_parse() */
138 assert(strcmp(opt->name, "id") != 0);
139
140 opts_visitor_insert(ov->unprocessed_opts, opt);
141 }
142
143 if (ov->opts_root->id != NULL) {
144 ov->fake_id_opt = g_malloc0(sizeof *ov->fake_id_opt);
145
146 ov->fake_id_opt->name = "id";
147 ov->fake_id_opt->str = ov->opts_root->id;
148 opts_visitor_insert(ov->unprocessed_opts, ov->fake_id_opt);
149 }
150 }
151
152
153 static gboolean
154 ghr_true(gpointer ign_key, gpointer ign_value, gpointer ign_user_data)
155 {
156 return TRUE;
157 }
158
159
160 static void
161 opts_end_struct(Visitor *v, Error **errp)
162 {
163 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
164 GQueue *any;
165
166 if (--ov->depth > 0) {
167 return;
168 }
169
170 /* we should have processed all (distinct) QemuOpt instances */
171 any = g_hash_table_find(ov->unprocessed_opts, &ghr_true, NULL);
172 if (any) {
173 const QemuOpt *first;
174
175 first = g_queue_peek_head(any);
176 error_set(errp, QERR_INVALID_PARAMETER, first->name);
177 }
178 g_hash_table_destroy(ov->unprocessed_opts);
179 ov->unprocessed_opts = NULL;
180 g_free(ov->fake_id_opt);
181 ov->fake_id_opt = NULL;
182 }
183
184
185 static GQueue *
186 lookup_distinct(const OptsVisitor *ov, const char *name, Error **errp)
187 {
188 GQueue *list;
189
190 list = g_hash_table_lookup(ov->unprocessed_opts, name);
191 if (!list) {
192 error_set(errp, QERR_MISSING_PARAMETER, name);
193 }
194 return list;
195 }
196
197
198 static void
199 opts_start_list(Visitor *v, const char *name, Error **errp)
200 {
201 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
202
203 /* we can't traverse a list in a list */
204 assert(ov->list_mode == LM_NONE);
205 ov->repeated_opts = lookup_distinct(ov, name, errp);
206 if (ov->repeated_opts != NULL) {
207 ov->list_mode = LM_STARTED;
208 }
209 }
210
211
212 static GenericList *
213 opts_next_list(Visitor *v, GenericList **list, Error **errp)
214 {
215 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
216 GenericList **link;
217
218 switch (ov->list_mode) {
219 case LM_STARTED:
220 ov->list_mode = LM_IN_PROGRESS;
221 link = list;
222 break;
223
224 case LM_SIGNED_INTERVAL:
225 case LM_UNSIGNED_INTERVAL:
226 link = &(*list)->next;
227
228 if (ov->list_mode == LM_SIGNED_INTERVAL) {
229 if (ov->range_next.s < ov->range_limit.s) {
230 ++ov->range_next.s;
231 break;
232 }
233 } else if (ov->range_next.u < ov->range_limit.u) {
234 ++ov->range_next.u;
235 break;
236 }
237 ov->list_mode = LM_IN_PROGRESS;
238 /* range has been completed, fall through in order to pop option */
239
240 case LM_IN_PROGRESS: {
241 const QemuOpt *opt;
242
243 opt = g_queue_pop_head(ov->repeated_opts);
244 if (g_queue_is_empty(ov->repeated_opts)) {
245 g_hash_table_remove(ov->unprocessed_opts, opt->name);
246 return NULL;
247 }
248 link = &(*list)->next;
249 break;
250 }
251
252 default:
253 abort();
254 }
255
256 *link = g_malloc0(sizeof **link);
257 return *link;
258 }
259
260
261 static void
262 opts_end_list(Visitor *v, Error **errp)
263 {
264 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
265
266 assert(ov->list_mode == LM_STARTED ||
267 ov->list_mode == LM_IN_PROGRESS ||
268 ov->list_mode == LM_SIGNED_INTERVAL ||
269 ov->list_mode == LM_UNSIGNED_INTERVAL);
270 ov->repeated_opts = NULL;
271 ov->list_mode = LM_NONE;
272 }
273
274
275 static const QemuOpt *
276 lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp)
277 {
278 if (ov->list_mode == LM_NONE) {
279 GQueue *list;
280
281 /* the last occurrence of any QemuOpt takes effect when queried by name
282 */
283 list = lookup_distinct(ov, name, errp);
284 return list ? g_queue_peek_tail(list) : NULL;
285 }
286 assert(ov->list_mode == LM_IN_PROGRESS);
287 return g_queue_peek_head(ov->repeated_opts);
288 }
289
290
291 static void
292 processed(OptsVisitor *ov, const char *name)
293 {
294 if (ov->list_mode == LM_NONE) {
295 g_hash_table_remove(ov->unprocessed_opts, name);
296 return;
297 }
298 assert(ov->list_mode == LM_IN_PROGRESS);
299 /* do nothing */
300 }
301
302
303 static void
304 opts_type_str(Visitor *v, char **obj, const char *name, Error **errp)
305 {
306 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
307 const QemuOpt *opt;
308
309 opt = lookup_scalar(ov, name, errp);
310 if (!opt) {
311 return;
312 }
313 *obj = g_strdup(opt->str ? opt->str : "");
314 processed(ov, name);
315 }
316
317
318 /* mimics qemu-option.c::parse_option_bool() */
319 static void
320 opts_type_bool(Visitor *v, bool *obj, const char *name, Error **errp)
321 {
322 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
323 const QemuOpt *opt;
324
325 opt = lookup_scalar(ov, name, errp);
326 if (!opt) {
327 return;
328 }
329
330 if (opt->str) {
331 if (strcmp(opt->str, "on") == 0 ||
332 strcmp(opt->str, "yes") == 0 ||
333 strcmp(opt->str, "y") == 0) {
334 *obj = true;
335 } else if (strcmp(opt->str, "off") == 0 ||
336 strcmp(opt->str, "no") == 0 ||
337 strcmp(opt->str, "n") == 0) {
338 *obj = false;
339 } else {
340 error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name,
341 "on|yes|y|off|no|n");
342 return;
343 }
344 } else {
345 *obj = true;
346 }
347
348 processed(ov, name);
349 }
350
351
352 static void
353 opts_type_int(Visitor *v, int64_t *obj, const char *name, Error **errp)
354 {
355 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
356 const QemuOpt *opt;
357 const char *str;
358 long long val;
359 char *endptr;
360
361 if (ov->list_mode == LM_SIGNED_INTERVAL) {
362 *obj = ov->range_next.s;
363 return;
364 }
365
366 opt = lookup_scalar(ov, name, errp);
367 if (!opt) {
368 return;
369 }
370 str = opt->str ? opt->str : "";
371
372 /* we've gotten past lookup_scalar() */
373 assert(ov->list_mode == LM_NONE || ov->list_mode == LM_IN_PROGRESS);
374
375 errno = 0;
376 val = strtoll(str, &endptr, 0);
377 if (errno == 0 && endptr > str && INT64_MIN <= val && val <= INT64_MAX) {
378 if (*endptr == '\0') {
379 *obj = val;
380 processed(ov, name);
381 return;
382 }
383 if (*endptr == '-' && ov->list_mode == LM_IN_PROGRESS) {
384 long long val2;
385
386 str = endptr + 1;
387 val2 = strtoll(str, &endptr, 0);
388 if (errno == 0 && endptr > str && *endptr == '\0' &&
389 INT64_MIN <= val2 && val2 <= INT64_MAX && val <= val2 &&
390 (val > INT64_MAX - OPTS_VISITOR_RANGE_MAX ||
391 val2 < val + OPTS_VISITOR_RANGE_MAX)) {
392 ov->range_next.s = val;
393 ov->range_limit.s = val2;
394 ov->list_mode = LM_SIGNED_INTERVAL;
395
396 /* as if entering on the top */
397 *obj = ov->range_next.s;
398 return;
399 }
400 }
401 }
402 error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name,
403 (ov->list_mode == LM_NONE) ? "an int64 value" :
404 "an int64 value or range");
405 }
406
407
408 static void
409 opts_type_uint64(Visitor *v, uint64_t *obj, const char *name, Error **errp)
410 {
411 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
412 const QemuOpt *opt;
413 const char *str;
414 unsigned long long val;
415 char *endptr;
416
417 if (ov->list_mode == LM_UNSIGNED_INTERVAL) {
418 *obj = ov->range_next.u;
419 return;
420 }
421
422 opt = lookup_scalar(ov, name, errp);
423 if (!opt) {
424 return;
425 }
426 str = opt->str;
427
428 /* we've gotten past lookup_scalar() */
429 assert(ov->list_mode == LM_NONE || ov->list_mode == LM_IN_PROGRESS);
430
431 if (parse_uint(str, &val, &endptr, 0) == 0 && val <= UINT64_MAX) {
432 if (*endptr == '\0') {
433 *obj = val;
434 processed(ov, name);
435 return;
436 }
437 if (*endptr == '-' && ov->list_mode == LM_IN_PROGRESS) {
438 unsigned long long val2;
439
440 str = endptr + 1;
441 if (parse_uint_full(str, &val2, 0) == 0 &&
442 val2 <= UINT64_MAX && val <= val2 &&
443 val2 - val < OPTS_VISITOR_RANGE_MAX) {
444 ov->range_next.u = val;
445 ov->range_limit.u = val2;
446 ov->list_mode = LM_UNSIGNED_INTERVAL;
447
448 /* as if entering on the top */
449 *obj = ov->range_next.u;
450 return;
451 }
452 }
453 }
454 error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name,
455 (ov->list_mode == LM_NONE) ? "a uint64 value" :
456 "a uint64 value or range");
457 }
458
459
460 static void
461 opts_type_size(Visitor *v, uint64_t *obj, const char *name, Error **errp)
462 {
463 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
464 const QemuOpt *opt;
465 int64_t val;
466 char *endptr;
467
468 opt = lookup_scalar(ov, name, errp);
469 if (!opt) {
470 return;
471 }
472
473 val = strtosz_suffix(opt->str ? opt->str : "", &endptr,
474 STRTOSZ_DEFSUFFIX_B);
475 if (val != -1 && *endptr == '\0') {
476 *obj = val;
477 processed(ov, name);
478 return;
479 }
480 error_set(errp, QERR_INVALID_PARAMETER_VALUE, opt->name,
481 "a size value representible as a non-negative int64");
482 }
483
484
485 static void
486 opts_start_optional(Visitor *v, bool *present, const char *name,
487 Error **errp)
488 {
489 OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v);
490
491 /* we only support a single mandatory scalar field in a list node */
492 assert(ov->list_mode == LM_NONE);
493 *present = (lookup_distinct(ov, name, NULL) != NULL);
494 }
495
496
497 OptsVisitor *
498 opts_visitor_new(const QemuOpts *opts)
499 {
500 OptsVisitor *ov;
501
502 ov = g_malloc0(sizeof *ov);
503
504 ov->visitor.start_struct = &opts_start_struct;
505 ov->visitor.end_struct = &opts_end_struct;
506
507 ov->visitor.start_list = &opts_start_list;
508 ov->visitor.next_list = &opts_next_list;
509 ov->visitor.end_list = &opts_end_list;
510
511 /* input_type_enum() covers both "normal" enums and union discriminators.
512 * The union discriminator field is always generated as "type"; it should
513 * match the "type" QemuOpt child of any QemuOpts.
514 *
515 * input_type_enum() will remove the looked-up key from the
516 * "unprocessed_opts" hash even if the lookup fails, because the removal is
517 * done earlier in opts_type_str(). This should be harmless.
518 */
519 ov->visitor.type_enum = &input_type_enum;
520
521 ov->visitor.type_int = &opts_type_int;
522 ov->visitor.type_uint64 = &opts_type_uint64;
523 ov->visitor.type_size = &opts_type_size;
524 ov->visitor.type_bool = &opts_type_bool;
525 ov->visitor.type_str = &opts_type_str;
526
527 /* type_number() is not filled in, but this is not the first visitor to
528 * skip some mandatory methods... */
529
530 ov->visitor.start_optional = &opts_start_optional;
531
532 ov->opts_root = opts;
533
534 return ov;
535 }
536
537
538 void
539 opts_visitor_cleanup(OptsVisitor *ov)
540 {
541 if (ov->unprocessed_opts != NULL) {
542 g_hash_table_destroy(ov->unprocessed_opts);
543 }
544 g_free(ov->fake_id_opt);
545 g_free(ov);
546 }
547
548
549 Visitor *
550 opts_get_visitor(OptsVisitor *ov)
551 {
552 return &ov->visitor;
553 }