| 1 | /* |
| 2 | * Options Visitor |
| 3 | * |
| 4 | * Copyright Red Hat, Inc. 2012-2016 |
| 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/osdep.h" |
| 14 | #include "qapi/error.h" |
| 15 | #include "qemu/cutils.h" |
| 16 | #include "qapi/qmp/qerror.h" |
| 17 | #include "qapi/opts-visitor.h" |
| 18 | #include "qemu/queue.h" |
| 19 | #include "qemu/option_int.h" |
| 20 | #include "qapi/visitor-impl.h" |
| 21 | |
| 22 | |
| 23 | enum ListMode |
| 24 | { |
| 25 | LM_NONE, /* not traversing a list of repeated options */ |
| 26 | |
| 27 | LM_IN_PROGRESS, /* |
| 28 | * opts_next_list() ready to be called. |
| 29 | * |
| 30 | * Generating the next list link will consume the most |
| 31 | * recently parsed QemuOpt instance of the repeated |
| 32 | * option. |
| 33 | * |
| 34 | * Parsing a value into the list link will examine the |
| 35 | * next QemuOpt instance of the repeated option, and |
| 36 | * possibly enter LM_SIGNED_INTERVAL or |
| 37 | * LM_UNSIGNED_INTERVAL. |
| 38 | */ |
| 39 | |
| 40 | LM_SIGNED_INTERVAL, /* |
| 41 | * opts_next_list() has been called. |
| 42 | * |
| 43 | * Generating the next list link will consume the most |
| 44 | * recently stored element from the signed interval, |
| 45 | * parsed from the most recent QemuOpt instance of the |
| 46 | * repeated option. This may consume QemuOpt itself |
| 47 | * and return to LM_IN_PROGRESS. |
| 48 | * |
| 49 | * Parsing a value into the list link will store the |
| 50 | * next element of the signed interval. |
| 51 | */ |
| 52 | |
| 53 | LM_UNSIGNED_INTERVAL, /* Same as above, only for an unsigned interval. */ |
| 54 | |
| 55 | LM_TRAVERSED /* |
| 56 | * opts_next_list() has been called. |
| 57 | * |
| 58 | * No more QemuOpt instance in the list. |
| 59 | * The traversal has been completed. |
| 60 | */ |
| 61 | }; |
| 62 | |
| 63 | typedef enum ListMode ListMode; |
| 64 | |
| 65 | struct OptsVisitor |
| 66 | { |
| 67 | Visitor visitor; |
| 68 | |
| 69 | /* Ownership remains with opts_visitor_new()'s caller. */ |
| 70 | const QemuOpts *opts_root; |
| 71 | |
| 72 | unsigned depth; |
| 73 | |
| 74 | /* Non-null iff depth is positive. Each key is a QemuOpt name. Each value |
| 75 | * is a non-empty GQueue, enumerating all QemuOpt occurrences with that |
| 76 | * name. */ |
| 77 | GHashTable *unprocessed_opts; |
| 78 | |
| 79 | /* The list currently being traversed with opts_start_list() / |
| 80 | * opts_next_list(). The list must have a struct element type in the |
| 81 | * schema, with a single mandatory scalar member. */ |
| 82 | ListMode list_mode; |
| 83 | GQueue *repeated_opts; |
| 84 | |
| 85 | /* When parsing a list of repeating options as integers, values of the form |
| 86 | * "a-b", representing a closed interval, are allowed. Elements in the |
| 87 | * range are generated individually. |
| 88 | */ |
| 89 | union { |
| 90 | int64_t s; |
| 91 | uint64_t u; |
| 92 | } range_next, range_limit; |
| 93 | |
| 94 | /* If "opts_root->id" is set, reinstantiate it as a fake QemuOpt for |
| 95 | * uniformity. Only its "name" and "str" fields are set. "fake_id_opt" does |
| 96 | * not survive or escape the OptsVisitor object. |
| 97 | */ |
| 98 | QemuOpt *fake_id_opt; |
| 99 | }; |
| 100 | |
| 101 | |
| 102 | static OptsVisitor *to_ov(Visitor *v) |
| 103 | { |
| 104 | return container_of(v, OptsVisitor, visitor); |
| 105 | } |
| 106 | |
| 107 | |
| 108 | static void |
| 109 | destroy_list(gpointer list) |
| 110 | { |
| 111 | g_queue_free(list); |
| 112 | } |
| 113 | |
| 114 | |
| 115 | static void |
| 116 | opts_visitor_insert(GHashTable *unprocessed_opts, const QemuOpt *opt) |
| 117 | { |
| 118 | GQueue *list; |
| 119 | |
| 120 | list = g_hash_table_lookup(unprocessed_opts, opt->name); |
| 121 | if (list == NULL) { |
| 122 | list = g_queue_new(); |
| 123 | |
| 124 | /* GHashTable will never try to free the keys -- we supply NULL as |
| 125 | * "key_destroy_func" in opts_start_struct(). Thus cast away key |
| 126 | * const-ness in order to suppress gcc's warning. |
| 127 | */ |
| 128 | g_hash_table_insert(unprocessed_opts, (gpointer)opt->name, list); |
| 129 | } |
| 130 | |
| 131 | /* Similarly, destroy_list() doesn't call g_queue_free_full(). */ |
| 132 | g_queue_push_tail(list, (gpointer)opt); |
| 133 | } |
| 134 | |
| 135 | |
| 136 | static bool |
| 137 | opts_start_struct(Visitor *v, const char *name, void **obj, |
| 138 | size_t size, Error **errp) |
| 139 | { |
| 140 | OptsVisitor *ov = to_ov(v); |
| 141 | const QemuOpt *opt; |
| 142 | |
| 143 | if (obj) { |
| 144 | *obj = g_malloc0(size); |
| 145 | } |
| 146 | if (ov->depth++ > 0) { |
| 147 | return true; |
| 148 | } |
| 149 | |
| 150 | ov->unprocessed_opts = g_hash_table_new_full(&g_str_hash, &g_str_equal, |
| 151 | NULL, &destroy_list); |
| 152 | QTAILQ_FOREACH(opt, &ov->opts_root->head, next) { |
| 153 | /* ensured by qemu-option.c::opts_do_parse() */ |
| 154 | assert(strcmp(opt->name, "id") != 0); |
| 155 | |
| 156 | opts_visitor_insert(ov->unprocessed_opts, opt); |
| 157 | } |
| 158 | |
| 159 | if (ov->opts_root->id != NULL) { |
| 160 | ov->fake_id_opt = g_malloc0(sizeof *ov->fake_id_opt); |
| 161 | |
| 162 | ov->fake_id_opt->name = g_strdup("id"); |
| 163 | ov->fake_id_opt->str = g_strdup(ov->opts_root->id); |
| 164 | opts_visitor_insert(ov->unprocessed_opts, ov->fake_id_opt); |
| 165 | } |
| 166 | return true; |
| 167 | } |
| 168 | |
| 169 | |
| 170 | static bool |
| 171 | opts_check_struct(Visitor *v, Error **errp) |
| 172 | { |
| 173 | OptsVisitor *ov = to_ov(v); |
| 174 | GHashTableIter iter; |
| 175 | GQueue *any; |
| 176 | |
| 177 | if (ov->depth > 1) { |
| 178 | return true; |
| 179 | } |
| 180 | |
| 181 | /* we should have processed all (distinct) QemuOpt instances */ |
| 182 | g_hash_table_iter_init(&iter, ov->unprocessed_opts); |
| 183 | if (g_hash_table_iter_next(&iter, NULL, (void **)&any)) { |
| 184 | const QemuOpt *first; |
| 185 | |
| 186 | first = g_queue_peek_head(any); |
| 187 | error_setg(errp, "Invalid parameter '%s'", first->name); |
| 188 | return false; |
| 189 | } |
| 190 | return true; |
| 191 | } |
| 192 | |
| 193 | |
| 194 | static void |
| 195 | opts_end_struct(Visitor *v, void **obj) |
| 196 | { |
| 197 | OptsVisitor *ov = to_ov(v); |
| 198 | |
| 199 | if (--ov->depth > 0) { |
| 200 | return; |
| 201 | } |
| 202 | |
| 203 | g_hash_table_destroy(ov->unprocessed_opts); |
| 204 | ov->unprocessed_opts = NULL; |
| 205 | if (ov->fake_id_opt) { |
| 206 | g_free(ov->fake_id_opt->name); |
| 207 | g_free(ov->fake_id_opt->str); |
| 208 | g_free(ov->fake_id_opt); |
| 209 | } |
| 210 | ov->fake_id_opt = NULL; |
| 211 | } |
| 212 | |
| 213 | |
| 214 | static GQueue * |
| 215 | lookup_distinct(const OptsVisitor *ov, const char *name, Error **errp) |
| 216 | { |
| 217 | GQueue *list; |
| 218 | |
| 219 | list = g_hash_table_lookup(ov->unprocessed_opts, name); |
| 220 | if (!list) { |
| 221 | error_setg(errp, QERR_MISSING_PARAMETER, name); |
| 222 | } |
| 223 | return list; |
| 224 | } |
| 225 | |
| 226 | |
| 227 | static bool |
| 228 | opts_start_list(Visitor *v, const char *name, GenericList **list, size_t size, |
| 229 | Error **errp) |
| 230 | { |
| 231 | OptsVisitor *ov = to_ov(v); |
| 232 | |
| 233 | /* we can't traverse a list in a list */ |
| 234 | assert(ov->list_mode == LM_NONE); |
| 235 | /* we don't support visits without a list */ |
| 236 | assert(list); |
| 237 | ov->repeated_opts = lookup_distinct(ov, name, errp); |
| 238 | if (!ov->repeated_opts) { |
| 239 | *list = NULL; |
| 240 | return false; |
| 241 | } |
| 242 | ov->list_mode = LM_IN_PROGRESS; |
| 243 | *list = g_malloc0(size); |
| 244 | return true; |
| 245 | } |
| 246 | |
| 247 | |
| 248 | static GenericList * |
| 249 | opts_next_list(Visitor *v, GenericList *tail, size_t size) |
| 250 | { |
| 251 | OptsVisitor *ov = to_ov(v); |
| 252 | |
| 253 | switch (ov->list_mode) { |
| 254 | case LM_TRAVERSED: |
| 255 | return NULL; |
| 256 | case LM_SIGNED_INTERVAL: |
| 257 | case LM_UNSIGNED_INTERVAL: |
| 258 | if (ov->list_mode == LM_SIGNED_INTERVAL) { |
| 259 | if (ov->range_next.s < ov->range_limit.s) { |
| 260 | ++ov->range_next.s; |
| 261 | break; |
| 262 | } |
| 263 | } else if (ov->range_next.u < ov->range_limit.u) { |
| 264 | ++ov->range_next.u; |
| 265 | break; |
| 266 | } |
| 267 | ov->list_mode = LM_IN_PROGRESS; |
| 268 | /* range has been completed, fall through in order to pop option */ |
| 269 | |
| 270 | case LM_IN_PROGRESS: { |
| 271 | const QemuOpt *opt; |
| 272 | |
| 273 | opt = g_queue_pop_head(ov->repeated_opts); |
| 274 | if (g_queue_is_empty(ov->repeated_opts)) { |
| 275 | g_hash_table_remove(ov->unprocessed_opts, opt->name); |
| 276 | ov->repeated_opts = NULL; |
| 277 | ov->list_mode = LM_TRAVERSED; |
| 278 | return NULL; |
| 279 | } |
| 280 | break; |
| 281 | } |
| 282 | |
| 283 | default: |
| 284 | abort(); |
| 285 | } |
| 286 | |
| 287 | tail->next = g_malloc0(size); |
| 288 | return tail->next; |
| 289 | } |
| 290 | |
| 291 | |
| 292 | static bool |
| 293 | opts_check_list(Visitor *v, Error **errp) |
| 294 | { |
| 295 | /* |
| 296 | * Unvisited list elements will be reported later when checking |
| 297 | * whether unvisited struct members remain. |
| 298 | */ |
| 299 | return true; |
| 300 | } |
| 301 | |
| 302 | |
| 303 | static void |
| 304 | opts_end_list(Visitor *v, void **obj) |
| 305 | { |
| 306 | OptsVisitor *ov = to_ov(v); |
| 307 | |
| 308 | assert(ov->list_mode == LM_IN_PROGRESS || |
| 309 | ov->list_mode == LM_SIGNED_INTERVAL || |
| 310 | ov->list_mode == LM_UNSIGNED_INTERVAL || |
| 311 | ov->list_mode == LM_TRAVERSED); |
| 312 | ov->repeated_opts = NULL; |
| 313 | ov->list_mode = LM_NONE; |
| 314 | } |
| 315 | |
| 316 | |
| 317 | static const QemuOpt * |
| 318 | lookup_scalar(const OptsVisitor *ov, const char *name, Error **errp) |
| 319 | { |
| 320 | if (ov->list_mode == LM_NONE) { |
| 321 | GQueue *list; |
| 322 | |
| 323 | /* the last occurrence of any QemuOpt takes effect when queried by name |
| 324 | */ |
| 325 | list = lookup_distinct(ov, name, errp); |
| 326 | return list ? g_queue_peek_tail(list) : NULL; |
| 327 | } |
| 328 | if (ov->list_mode == LM_TRAVERSED) { |
| 329 | error_setg(errp, "Fewer list elements than expected"); |
| 330 | return NULL; |
| 331 | } |
| 332 | assert(ov->list_mode == LM_IN_PROGRESS); |
| 333 | return g_queue_peek_head(ov->repeated_opts); |
| 334 | } |
| 335 | |
| 336 | |
| 337 | static void |
| 338 | processed(OptsVisitor *ov, const char *name) |
| 339 | { |
| 340 | if (ov->list_mode == LM_NONE) { |
| 341 | g_hash_table_remove(ov->unprocessed_opts, name); |
| 342 | return; |
| 343 | } |
| 344 | assert(ov->list_mode == LM_IN_PROGRESS); |
| 345 | /* do nothing */ |
| 346 | } |
| 347 | |
| 348 | |
| 349 | static bool |
| 350 | opts_type_str(Visitor *v, const char *name, char **obj, Error **errp) |
| 351 | { |
| 352 | OptsVisitor *ov = to_ov(v); |
| 353 | const QemuOpt *opt; |
| 354 | |
| 355 | opt = lookup_scalar(ov, name, errp); |
| 356 | if (!opt) { |
| 357 | *obj = NULL; |
| 358 | return false; |
| 359 | } |
| 360 | *obj = g_strdup(opt->str ? opt->str : ""); |
| 361 | /* Note that we consume a string even if this is called as part of |
| 362 | * an enum visit that later fails because the string is not a |
| 363 | * valid enum value; this is harmless because tracking what gets |
| 364 | * consumed only matters to visit_end_struct() as the final error |
| 365 | * check if there were no other failures during the visit. */ |
| 366 | processed(ov, name); |
| 367 | return true; |
| 368 | } |
| 369 | |
| 370 | |
| 371 | static bool |
| 372 | opts_type_bool(Visitor *v, const char *name, bool *obj, Error **errp) |
| 373 | { |
| 374 | OptsVisitor *ov = to_ov(v); |
| 375 | const QemuOpt *opt; |
| 376 | |
| 377 | opt = lookup_scalar(ov, name, errp); |
| 378 | if (!opt) { |
| 379 | return false; |
| 380 | } |
| 381 | if (opt->str) { |
| 382 | if (!qapi_bool_parse(opt->name, opt->str, obj, errp)) { |
| 383 | return false; |
| 384 | } |
| 385 | } else { |
| 386 | *obj = true; |
| 387 | } |
| 388 | |
| 389 | processed(ov, name); |
| 390 | return true; |
| 391 | } |
| 392 | |
| 393 | |
| 394 | static bool |
| 395 | opts_type_int64(Visitor *v, const char *name, int64_t *obj, Error **errp) |
| 396 | { |
| 397 | OptsVisitor *ov = to_ov(v); |
| 398 | const QemuOpt *opt; |
| 399 | const char *str; |
| 400 | long long val; |
| 401 | char *endptr; |
| 402 | |
| 403 | if (ov->list_mode == LM_SIGNED_INTERVAL) { |
| 404 | *obj = ov->range_next.s; |
| 405 | return true; |
| 406 | } |
| 407 | |
| 408 | opt = lookup_scalar(ov, name, errp); |
| 409 | if (!opt) { |
| 410 | return false; |
| 411 | } |
| 412 | str = opt->str ? opt->str : ""; |
| 413 | |
| 414 | /* we've gotten past lookup_scalar() */ |
| 415 | assert(ov->list_mode == LM_NONE || ov->list_mode == LM_IN_PROGRESS); |
| 416 | |
| 417 | errno = 0; |
| 418 | val = strtoll(str, &endptr, 0); |
| 419 | if (errno == 0 && endptr > str && INT64_MIN <= val && val <= INT64_MAX) { |
| 420 | if (*endptr == '\0') { |
| 421 | *obj = val; |
| 422 | processed(ov, name); |
| 423 | return true; |
| 424 | } |
| 425 | if (*endptr == '-' && ov->list_mode == LM_IN_PROGRESS) { |
| 426 | long long val2; |
| 427 | |
| 428 | str = endptr + 1; |
| 429 | val2 = strtoll(str, &endptr, 0); |
| 430 | if (errno == 0 && endptr > str && *endptr == '\0' && |
| 431 | INT64_MIN <= val2 && val2 <= INT64_MAX && val <= val2 && |
| 432 | (val > INT64_MAX - OPTS_VISITOR_RANGE_MAX || |
| 433 | val2 < val + OPTS_VISITOR_RANGE_MAX)) { |
| 434 | ov->range_next.s = val; |
| 435 | ov->range_limit.s = val2; |
| 436 | ov->list_mode = LM_SIGNED_INTERVAL; |
| 437 | |
| 438 | /* as if entering on the top */ |
| 439 | *obj = ov->range_next.s; |
| 440 | return true; |
| 441 | } |
| 442 | } |
| 443 | } |
| 444 | error_setg(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, |
| 445 | (ov->list_mode == LM_NONE) ? "an int64 value" : |
| 446 | "an int64 value or range"); |
| 447 | return false; |
| 448 | } |
| 449 | |
| 450 | |
| 451 | static bool |
| 452 | opts_type_uint64(Visitor *v, const char *name, uint64_t *obj, Error **errp) |
| 453 | { |
| 454 | OptsVisitor *ov = to_ov(v); |
| 455 | const QemuOpt *opt; |
| 456 | const char *str; |
| 457 | uint64_t val; |
| 458 | const char *endptr; |
| 459 | |
| 460 | if (ov->list_mode == LM_UNSIGNED_INTERVAL) { |
| 461 | *obj = ov->range_next.u; |
| 462 | return true; |
| 463 | } |
| 464 | |
| 465 | opt = lookup_scalar(ov, name, errp); |
| 466 | if (!opt) { |
| 467 | return false; |
| 468 | } |
| 469 | str = opt->str; |
| 470 | |
| 471 | /* we've gotten past lookup_scalar() */ |
| 472 | assert(ov->list_mode == LM_NONE || ov->list_mode == LM_IN_PROGRESS); |
| 473 | |
| 474 | if (parse_uint(str, &endptr, 0, &val) == 0) { |
| 475 | if (*endptr == '\0') { |
| 476 | *obj = val; |
| 477 | processed(ov, name); |
| 478 | return true; |
| 479 | } |
| 480 | if (*endptr == '-' && ov->list_mode == LM_IN_PROGRESS) { |
| 481 | uint64_t val2; |
| 482 | |
| 483 | str = endptr + 1; |
| 484 | if (parse_uint_full(str, 0, &val2) == 0 && |
| 485 | val <= val2 && |
| 486 | val2 - val < OPTS_VISITOR_RANGE_MAX) { |
| 487 | ov->range_next.u = val; |
| 488 | ov->range_limit.u = val2; |
| 489 | ov->list_mode = LM_UNSIGNED_INTERVAL; |
| 490 | |
| 491 | /* as if entering on the top */ |
| 492 | *obj = ov->range_next.u; |
| 493 | return true; |
| 494 | } |
| 495 | } |
| 496 | } |
| 497 | error_setg(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, |
| 498 | (ov->list_mode == LM_NONE) ? "a uint64 value" : |
| 499 | "a uint64 value or range"); |
| 500 | return false; |
| 501 | } |
| 502 | |
| 503 | |
| 504 | static bool |
| 505 | opts_type_size(Visitor *v, const char *name, uint64_t *obj, Error **errp) |
| 506 | { |
| 507 | OptsVisitor *ov = to_ov(v); |
| 508 | const QemuOpt *opt; |
| 509 | int err; |
| 510 | |
| 511 | opt = lookup_scalar(ov, name, errp); |
| 512 | if (!opt) { |
| 513 | return false; |
| 514 | } |
| 515 | |
| 516 | err = qemu_strtosz(opt->str ? opt->str : "", NULL, obj); |
| 517 | if (err < 0) { |
| 518 | error_setg(errp, QERR_INVALID_PARAMETER_VALUE, opt->name, |
| 519 | "a size value"); |
| 520 | return false; |
| 521 | } |
| 522 | |
| 523 | processed(ov, name); |
| 524 | return true; |
| 525 | } |
| 526 | |
| 527 | |
| 528 | static void |
| 529 | opts_optional(Visitor *v, const char *name, bool *present) |
| 530 | { |
| 531 | OptsVisitor *ov = to_ov(v); |
| 532 | |
| 533 | /* we only support a single mandatory scalar field in a list node */ |
| 534 | assert(ov->list_mode == LM_NONE); |
| 535 | *present = (lookup_distinct(ov, name, NULL) != NULL); |
| 536 | } |
| 537 | |
| 538 | |
| 539 | static void |
| 540 | opts_free(Visitor *v) |
| 541 | { |
| 542 | OptsVisitor *ov = to_ov(v); |
| 543 | |
| 544 | if (ov->unprocessed_opts != NULL) { |
| 545 | g_hash_table_destroy(ov->unprocessed_opts); |
| 546 | } |
| 547 | g_free(ov->fake_id_opt); |
| 548 | g_free(ov); |
| 549 | } |
| 550 | |
| 551 | |
| 552 | Visitor * |
| 553 | opts_visitor_new(const QemuOpts *opts) |
| 554 | { |
| 555 | OptsVisitor *ov; |
| 556 | |
| 557 | assert(opts); |
| 558 | ov = g_malloc0(sizeof *ov); |
| 559 | |
| 560 | ov->visitor.type = VISITOR_INPUT; |
| 561 | |
| 562 | ov->visitor.start_struct = &opts_start_struct; |
| 563 | ov->visitor.check_struct = &opts_check_struct; |
| 564 | ov->visitor.end_struct = &opts_end_struct; |
| 565 | |
| 566 | ov->visitor.start_list = &opts_start_list; |
| 567 | ov->visitor.next_list = &opts_next_list; |
| 568 | ov->visitor.check_list = &opts_check_list; |
| 569 | ov->visitor.end_list = &opts_end_list; |
| 570 | |
| 571 | ov->visitor.type_int64 = &opts_type_int64; |
| 572 | ov->visitor.type_uint64 = &opts_type_uint64; |
| 573 | ov->visitor.type_size = &opts_type_size; |
| 574 | ov->visitor.type_bool = &opts_type_bool; |
| 575 | ov->visitor.type_str = &opts_type_str; |
| 576 | |
| 577 | /* type_number() is not filled in, but this is not the first visitor to |
| 578 | * skip some mandatory methods... */ |
| 579 | |
| 580 | ov->visitor.optional = &opts_optional; |
| 581 | ov->visitor.free = opts_free; |
| 582 | |
| 583 | ov->opts_root = opts; |
| 584 | |
| 585 | return &ov->visitor; |
| 586 | } |