1 /*- 2 * Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/time.h> 32 #include <assert.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include "cachelib.h" 36 #include "debug.h" 37 38 #define INITIAL_ENTRIES_CAPACITY 32 39 #define ENTRIES_CAPACITY_STEP 32 40 41 #define STRING_SIMPLE_HASH_BODY(in_var, var, a, M) \ 42 for ((var) = 0; *(in_var) != '\0'; ++(in_var)) \ 43 (var) = ((a)*(var) + *(in_var)) % (M) 44 45 #define STRING_SIMPLE_MP2_HASH_BODY(in_var, var, a, M) \ 46 for ((var) = 0; *(in_var) != 0; ++(in_var)) \ 47 (var) = ((a)*(var) + *(in_var)) & (M - 1) 48 49 static int cache_elemsize_common_continue_func(struct cache_common_entry_ *, 50 struct cache_policy_item_ *); 51 static int cache_lifetime_common_continue_func(struct cache_common_entry_ *, 52 struct cache_policy_item_ *); 53 static void clear_cache_entry(struct cache_entry_ *); 54 static void destroy_cache_entry(struct cache_entry_ *); 55 static void destroy_cache_mp_read_session(struct cache_mp_read_session_ *); 56 static void destroy_cache_mp_write_session(struct cache_mp_write_session_ *); 57 static int entries_bsearch_cmp_func(const void *, const void *); 58 static int entries_qsort_cmp_func(const void *, const void *); 59 static struct cache_entry_ ** find_cache_entry_p(struct cache_ *, 60 const char *); 61 static void flush_cache_entry(struct cache_entry_ *); 62 static void flush_cache_policy(struct cache_common_entry_ *, 63 struct cache_policy_ *, struct cache_policy_ *, 64 int (*)(struct cache_common_entry_ *, 65 struct cache_policy_item_ *)); 66 static int ht_items_cmp_func(const void *, const void *); 67 static int ht_items_fixed_size_left_cmp_func(const void *, const void *); 68 static hashtable_index_t ht_item_hash_func(const void *, size_t); 69 70 /* 71 * Hashing and comparing routines, that are used with the hash tables 72 */ 73 static int 74 ht_items_cmp_func(const void *p1, const void *p2) 75 { 76 struct cache_ht_item_data_ *hp1, *hp2; 77 size_t min_size; 78 int result; 79 80 hp1 = (struct cache_ht_item_data_ *)p1; 81 hp2 = (struct cache_ht_item_data_ *)p2; 82 83 assert(hp1->key != NULL); 84 assert(hp2->key != NULL); 85 86 if (hp1->key_size != hp2->key_size) { 87 min_size = (hp1->key_size < hp2->key_size) ? hp1->key_size : 88 hp2->key_size; 89 result = memcmp(hp1->key, hp2->key, min_size); 90 91 if (result == 0) 92 return ((hp1->key_size < hp2->key_size) ? -1 : 1); 93 else 94 return (result); 95 } else 96 return (memcmp(hp1->key, hp2->key, hp1->key_size)); 97 } 98 99 static int 100 ht_items_fixed_size_left_cmp_func(const void *p1, const void *p2) 101 { 102 struct cache_ht_item_data_ *hp1, *hp2; 103 size_t min_size; 104 int result; 105 106 hp1 = (struct cache_ht_item_data_ *)p1; 107 hp2 = (struct cache_ht_item_data_ *)p2; 108 109 assert(hp1->key != NULL); 110 assert(hp2->key != NULL); 111 112 if (hp1->key_size != hp2->key_size) { 113 min_size = (hp1->key_size < hp2->key_size) ? hp1->key_size : 114 hp2->key_size; 115 result = memcmp(hp1->key, hp2->key, min_size); 116 117 if (result == 0) 118 if (min_size == hp1->key_size) 119 return (0); 120 else 121 return ((hp1->key_size < hp2->key_size) ? -1 : 1); 122 else 123 return (result); 124 } else 125 return (memcmp(hp1->key, hp2->key, hp1->key_size)); 126 } 127 128 static hashtable_index_t 129 ht_item_hash_func(const void *p, size_t cache_entries_size) 130 { 131 struct cache_ht_item_data_ *hp; 132 size_t i; 133 134 hashtable_index_t retval; 135 136 hp = (struct cache_ht_item_data_ *)p; 137 assert(hp->key != NULL); 138 139 retval = 0; 140 for (i = 0; i < hp->key_size; ++i) 141 retval = (127 * retval + (unsigned char)hp->key[i]) % 142 cache_entries_size; 143 144 return retval; 145 } 146 147 HASHTABLE_GENERATE(cache_ht_, cache_ht_item_, struct cache_ht_item_data_, data, 148 ht_item_hash_func, ht_items_cmp_func); 149 150 /* 151 * Routines to sort and search the entries by name 152 */ 153 static int 154 entries_bsearch_cmp_func(const void *key, const void *ent) 155 { 156 157 assert(key != NULL); 158 assert(ent != NULL); 159 160 return (strcmp((char const *)key, 161 (*(struct cache_entry_ const **)ent)->name)); 162 } 163 164 static int 165 entries_qsort_cmp_func(const void *e1, const void *e2) 166 { 167 168 assert(e1 != NULL); 169 assert(e2 != NULL); 170 171 return (strcmp((*(struct cache_entry_ const **)e1)->name, 172 (*(struct cache_entry_ const **)e2)->name)); 173 } 174 175 static struct cache_entry_ ** 176 find_cache_entry_p(struct cache_ *the_cache, const char *entry_name) 177 { 178 179 return ((struct cache_entry_ **)(bsearch(entry_name, the_cache->entries, 180 the_cache->entries_size, sizeof(struct cache_entry_ *), 181 entries_bsearch_cmp_func))); 182 } 183 184 static void 185 destroy_cache_mp_write_session(struct cache_mp_write_session_ *ws) 186 { 187 188 struct cache_mp_data_item_ *data_item; 189 190 TRACE_IN(destroy_cache_mp_write_session); 191 assert(ws != NULL); 192 while (!TAILQ_EMPTY(&ws->items)) { 193 data_item = TAILQ_FIRST(&ws->items); 194 TAILQ_REMOVE(&ws->items, data_item, entries); 195 free(data_item->value); 196 free(data_item); 197 } 198 199 free(ws); 200 TRACE_OUT(destroy_cache_mp_write_session); 201 } 202 203 static void 204 destroy_cache_mp_read_session(struct cache_mp_read_session_ *rs) 205 { 206 207 TRACE_IN(destroy_cache_mp_read_session); 208 assert(rs != NULL); 209 free(rs); 210 TRACE_OUT(destroy_cache_mp_read_session); 211 } 212 213 static void 214 destroy_cache_entry(struct cache_entry_ *entry) 215 { 216 struct cache_common_entry_ *common_entry; 217 struct cache_mp_entry_ *mp_entry; 218 struct cache_mp_read_session_ *rs; 219 struct cache_mp_write_session_ *ws; 220 struct cache_ht_item_ *ht_item; 221 struct cache_ht_item_data_ *ht_item_data; 222 223 TRACE_IN(destroy_cache_entry); 224 assert(entry != NULL); 225 226 if (entry->params->entry_type == CET_COMMON) { 227 common_entry = (struct cache_common_entry_ *)entry; 228 229 HASHTABLE_FOREACH(&(common_entry->items), ht_item) { 230 HASHTABLE_ENTRY_FOREACH(ht_item, data, ht_item_data) 231 { 232 free(ht_item_data->key); 233 free(ht_item_data->value); 234 } 235 HASHTABLE_ENTRY_CLEAR(ht_item, data); 236 } 237 238 HASHTABLE_DESTROY(&(common_entry->items), data); 239 240 /* FIFO policy is always first */ 241 destroy_cache_fifo_policy(common_entry->policies[0]); 242 switch (common_entry->common_params.policy) { 243 case CPT_LRU: 244 destroy_cache_lru_policy(common_entry->policies[1]); 245 break; 246 case CPT_LFU: 247 destroy_cache_lfu_policy(common_entry->policies[1]); 248 break; 249 default: 250 break; 251 } 252 free(common_entry->policies); 253 } else { 254 mp_entry = (struct cache_mp_entry_ *)entry; 255 256 while (!TAILQ_EMPTY(&mp_entry->ws_head)) { 257 ws = TAILQ_FIRST(&mp_entry->ws_head); 258 TAILQ_REMOVE(&mp_entry->ws_head, ws, entries); 259 destroy_cache_mp_write_session(ws); 260 } 261 262 while (!TAILQ_EMPTY(&mp_entry->rs_head)) { 263 rs = TAILQ_FIRST(&mp_entry->rs_head); 264 TAILQ_REMOVE(&mp_entry->rs_head, rs, entries); 265 destroy_cache_mp_read_session(rs); 266 } 267 268 if (mp_entry->completed_write_session != NULL) 269 destroy_cache_mp_write_session( 270 mp_entry->completed_write_session); 271 272 if (mp_entry->pending_write_session != NULL) 273 destroy_cache_mp_write_session( 274 mp_entry->pending_write_session); 275 } 276 277 free(entry->name); 278 free(entry); 279 TRACE_OUT(destroy_cache_entry); 280 } 281 282 static void 283 clear_cache_entry(struct cache_entry_ *entry) 284 { 285 struct cache_mp_entry_ *mp_entry; 286 struct cache_common_entry_ *common_entry; 287 struct cache_ht_item_ *ht_item; 288 struct cache_ht_item_data_ *ht_item_data; 289 struct cache_policy_ *policy; 290 struct cache_policy_item_ *item, *next_item; 291 size_t entry_size; 292 int i; 293 294 if (entry->params->entry_type == CET_COMMON) { 295 common_entry = (struct cache_common_entry_ *)entry; 296 297 entry_size = 0; 298 HASHTABLE_FOREACH(&(common_entry->items), ht_item) { 299 HASHTABLE_ENTRY_FOREACH(ht_item, data, ht_item_data) 300 { 301 free(ht_item_data->key); 302 free(ht_item_data->value); 303 } 304 entry_size += HASHTABLE_ENTRY_SIZE(ht_item, data); 305 HASHTABLE_ENTRY_CLEAR(ht_item, data); 306 } 307 308 common_entry->items_size -= entry_size; 309 for (i = 0; i < common_entry->policies_size; ++i) { 310 policy = common_entry->policies[i]; 311 312 next_item = NULL; 313 item = policy->get_first_item_func(policy); 314 while (item != NULL) { 315 next_item = policy->get_next_item_func(policy, 316 item); 317 policy->remove_item_func(policy, item); 318 policy->destroy_item_func(item); 319 item = next_item; 320 } 321 } 322 } else { 323 mp_entry = (struct cache_mp_entry_ *)entry; 324 325 if (mp_entry->rs_size == 0) { 326 if (mp_entry->completed_write_session != NULL) { 327 destroy_cache_mp_write_session( 328 mp_entry->completed_write_session); 329 mp_entry->completed_write_session = NULL; 330 } 331 332 memset(&mp_entry->creation_time, 0, 333 sizeof(struct timeval)); 334 memset(&mp_entry->last_request_time, 0, 335 sizeof(struct timeval)); 336 } 337 } 338 } 339 340 /* 341 * When passed to the flush_cache_policy, ensures that all old elements are 342 * deleted. 343 */ 344 static int 345 cache_lifetime_common_continue_func(struct cache_common_entry_ *entry, 346 struct cache_policy_item_ *item) 347 { 348 349 return ((item->last_request_time.tv_sec - item->creation_time.tv_sec > 350 entry->common_params.max_lifetime.tv_sec) ? 1: 0); 351 } 352 353 /* 354 * When passed to the flush_cache_policy, ensures that all elements, that 355 * exceed the size limit, are deleted. 356 */ 357 static int 358 cache_elemsize_common_continue_func(struct cache_common_entry_ *entry, 359 struct cache_policy_item_ *item) 360 { 361 362 return ((entry->items_size > entry->common_params.satisf_elemsize) ? 1 363 : 0); 364 } 365 366 /* 367 * Removes the elements from the cache entry, while the continue_func returns 1. 368 */ 369 static void 370 flush_cache_policy(struct cache_common_entry_ *entry, 371 struct cache_policy_ *policy, 372 struct cache_policy_ *connected_policy, 373 int (*continue_func)(struct cache_common_entry_ *, 374 struct cache_policy_item_ *)) 375 { 376 struct cache_policy_item_ *item, *next_item, *connected_item; 377 struct cache_ht_item_ *ht_item; 378 struct cache_ht_item_data_ *ht_item_data, ht_key; 379 hashtable_index_t hash; 380 381 assert(policy != NULL); 382 383 next_item = NULL; 384 item = policy->get_first_item_func(policy); 385 while ((item != NULL) && (continue_func(entry, item) == 1)) { 386 next_item = policy->get_next_item_func(policy, item); 387 388 connected_item = item->connected_item; 389 policy->remove_item_func(policy, item); 390 391 memset(&ht_key, 0, sizeof(struct cache_ht_item_data_)); 392 ht_key.key = item->key; 393 ht_key.key_size = item->key_size; 394 395 hash = HASHTABLE_CALCULATE_HASH(cache_ht_, &entry->items, 396 &ht_key); 397 assert(hash >= 0); 398 assert(hash < HASHTABLE_ENTRIES_COUNT(&entry->items)); 399 400 ht_item = HASHTABLE_GET_ENTRY(&(entry->items), hash); 401 ht_item_data = HASHTABLE_ENTRY_FIND(cache_ht_, ht_item, 402 &ht_key); 403 assert(ht_item_data != NULL); 404 free(ht_item_data->key); 405 free(ht_item_data->value); 406 HASHTABLE_ENTRY_REMOVE(cache_ht_, ht_item, ht_item_data); 407 --entry->items_size; 408 409 policy->destroy_item_func(item); 410 411 if (connected_item != NULL) { 412 connected_policy->remove_item_func(connected_policy, 413 connected_item); 414 connected_policy->destroy_item_func(connected_item); 415 } 416 417 item = next_item; 418 } 419 } 420 421 static void 422 flush_cache_entry(struct cache_entry_ *entry) 423 { 424 struct cache_mp_entry_ *mp_entry; 425 struct cache_common_entry_ *common_entry; 426 struct cache_policy_ *policy, *connected_policy; 427 428 connected_policy = NULL; 429 if (entry->params->entry_type == CET_COMMON) { 430 common_entry = (struct cache_common_entry_ *)entry; 431 if ((common_entry->common_params.max_lifetime.tv_sec != 0) || 432 (common_entry->common_params.max_lifetime.tv_usec != 0)) { 433 434 policy = common_entry->policies[0]; 435 if (common_entry->policies_size > 1) 436 connected_policy = common_entry->policies[1]; 437 438 flush_cache_policy(common_entry, policy, 439 connected_policy, 440 cache_lifetime_common_continue_func); 441 } 442 443 444 if ((common_entry->common_params.max_elemsize != 0) && 445 common_entry->items_size > 446 common_entry->common_params.max_elemsize) { 447 448 if (common_entry->policies_size > 1) { 449 policy = common_entry->policies[1]; 450 connected_policy = common_entry->policies[0]; 451 } else { 452 policy = common_entry->policies[0]; 453 connected_policy = NULL; 454 } 455 456 flush_cache_policy(common_entry, policy, 457 connected_policy, 458 cache_elemsize_common_continue_func); 459 } 460 } else { 461 mp_entry = (struct cache_mp_entry_ *)entry; 462 463 if ((mp_entry->mp_params.max_lifetime.tv_sec != 0) 464 || (mp_entry->mp_params.max_lifetime.tv_usec != 0)) { 465 466 if (mp_entry->last_request_time.tv_sec - 467 mp_entry->last_request_time.tv_sec > 468 mp_entry->mp_params.max_lifetime.tv_sec) 469 clear_cache_entry(entry); 470 } 471 } 472 } 473 474 struct cache_ * 475 init_cache(struct cache_params const *params) 476 { 477 struct cache_ *retval; 478 479 TRACE_IN(init_cache); 480 assert(params != NULL); 481 482 retval = (struct cache_ *)calloc(1, sizeof(struct cache_)); 483 assert(retval != NULL); 484 485 assert(params != NULL); 486 memcpy(&retval->params, params, sizeof(struct cache_params)); 487 488 retval->entries = (struct cache_entry_ **)calloc(1, 489 sizeof(struct cache_entry_ *) * INITIAL_ENTRIES_CAPACITY); 490 assert(retval->entries != NULL); 491 492 retval->entries_capacity = INITIAL_ENTRIES_CAPACITY; 493 retval->entries_size = 0; 494 495 TRACE_OUT(init_cache); 496 return (retval); 497 } 498 499 void 500 destroy_cache(struct cache_ *the_cache) 501 { 502 503 TRACE_IN(destroy_cache); 504 assert(the_cache != NULL); 505 506 if (the_cache->entries != NULL) { 507 size_t i; 508 for (i = 0; i < the_cache->entries_size; ++i) 509 destroy_cache_entry(the_cache->entries[i]); 510 511 free(the_cache->entries); 512 } 513 514 free(the_cache); 515 TRACE_OUT(destroy_cache); 516 } 517 518 int 519 register_cache_entry(struct cache_ *the_cache, 520 struct cache_entry_params const *params) 521 { 522 int policies_size; 523 size_t entry_name_size; 524 struct cache_common_entry_ *new_common_entry; 525 struct cache_mp_entry_ *new_mp_entry; 526 527 TRACE_IN(register_cache_entry); 528 assert(the_cache != NULL); 529 530 if (find_cache_entry(the_cache, params->entry_name) != NULL) { 531 TRACE_OUT(register_cache_entry); 532 return (-1); 533 } 534 535 if (the_cache->entries_size == the_cache->entries_capacity) { 536 struct cache_entry_ **new_entries; 537 size_t new_capacity; 538 539 new_capacity = the_cache->entries_capacity + 540 ENTRIES_CAPACITY_STEP; 541 new_entries = (struct cache_entry_ **)calloc(1, 542 sizeof(struct cache_entry_ *) * new_capacity); 543 assert(new_entries != NULL); 544 545 memcpy(new_entries, the_cache->entries, 546 sizeof(struct cache_entry_ *) 547 * the_cache->entries_size); 548 549 free(the_cache->entries); 550 the_cache->entries = new_entries; 551 } 552 553 entry_name_size = strlen(params->entry_name) + 1; 554 switch (params->entry_type) 555 { 556 case CET_COMMON: 557 new_common_entry = (struct cache_common_entry_ *)calloc(1, 558 sizeof(struct cache_common_entry_)); 559 assert(new_common_entry != NULL); 560 561 memcpy(&new_common_entry->common_params, params, 562 sizeof(struct common_cache_entry_params)); 563 new_common_entry->params = 564 (struct cache_entry_params *)&new_common_entry->common_params; 565 566 new_common_entry->common_params.entry_name = (char *)calloc(1, 567 entry_name_size); 568 assert(new_common_entry->common_params.entry_name != NULL); 569 strlcpy(new_common_entry->common_params.entry_name, 570 params->entry_name, entry_name_size); 571 new_common_entry->name = 572 new_common_entry->common_params.entry_name; 573 574 HASHTABLE_INIT(&(new_common_entry->items), 575 struct cache_ht_item_data_, data, 576 new_common_entry->common_params.cache_entries_size); 577 578 if (new_common_entry->common_params.policy == CPT_FIFO) 579 policies_size = 1; 580 else 581 policies_size = 2; 582 583 new_common_entry->policies = (struct cache_policy_ **)calloc(1, 584 sizeof(struct cache_policy_ *) * policies_size); 585 assert(new_common_entry->policies != NULL); 586 587 new_common_entry->policies_size = policies_size; 588 new_common_entry->policies[0] = init_cache_fifo_policy(); 589 590 if (policies_size > 1) { 591 switch (new_common_entry->common_params.policy) { 592 case CPT_LRU: 593 new_common_entry->policies[1] = 594 init_cache_lru_policy(); 595 break; 596 case CPT_LFU: 597 new_common_entry->policies[1] = 598 init_cache_lfu_policy(); 599 break; 600 default: 601 break; 602 } 603 } 604 605 new_common_entry->get_time_func = 606 the_cache->params.get_time_func; 607 the_cache->entries[the_cache->entries_size++] = 608 (struct cache_entry_ *)new_common_entry; 609 break; 610 case CET_MULTIPART: 611 new_mp_entry = (struct cache_mp_entry_ *)calloc(1, 612 sizeof(struct cache_mp_entry_)); 613 assert(new_mp_entry != NULL); 614 615 memcpy(&new_mp_entry->mp_params, params, 616 sizeof(struct mp_cache_entry_params)); 617 new_mp_entry->params = 618 (struct cache_entry_params *)&new_mp_entry->mp_params; 619 620 new_mp_entry->mp_params.entry_name = (char *)calloc(1, 621 entry_name_size); 622 assert(new_mp_entry->mp_params.entry_name != NULL); 623 strlcpy(new_mp_entry->mp_params.entry_name, params->entry_name, 624 entry_name_size); 625 new_mp_entry->name = new_mp_entry->mp_params.entry_name; 626 627 TAILQ_INIT(&new_mp_entry->ws_head); 628 TAILQ_INIT(&new_mp_entry->rs_head); 629 630 new_mp_entry->get_time_func = the_cache->params.get_time_func; 631 the_cache->entries[the_cache->entries_size++] = 632 (struct cache_entry_ *)new_mp_entry; 633 break; 634 } 635 636 637 qsort(the_cache->entries, the_cache->entries_size, 638 sizeof(struct cache_entry_ *), entries_qsort_cmp_func); 639 640 TRACE_OUT(register_cache_entry); 641 return (0); 642 } 643 644 int 645 unregister_cache_entry(struct cache_ *the_cache, const char *entry_name) 646 { 647 struct cache_entry_ **del_ent; 648 649 TRACE_IN(unregister_cache_entry); 650 assert(the_cache != NULL); 651 652 del_ent = find_cache_entry_p(the_cache, entry_name); 653 if (del_ent != NULL) { 654 destroy_cache_entry(*del_ent); 655 --the_cache->entries_size; 656 657 memmove(del_ent, del_ent + 1, 658 (&(the_cache->entries[--the_cache->entries_size]) - 659 del_ent) * sizeof(struct cache_entry_ *)); 660 661 TRACE_OUT(unregister_cache_entry); 662 return (0); 663 } else { 664 TRACE_OUT(unregister_cache_entry); 665 return (-1); 666 } 667 } 668 669 struct cache_entry_ * 670 find_cache_entry(struct cache_ *the_cache, const char *entry_name) 671 { 672 struct cache_entry_ **result; 673 674 TRACE_IN(find_cache_entry); 675 result = find_cache_entry_p(the_cache, entry_name); 676 677 if (result == NULL) { 678 TRACE_OUT(find_cache_entry); 679 return (NULL); 680 } else { 681 TRACE_OUT(find_cache_entry); 682 return (*result); 683 } 684 } 685 686 /* 687 * Tries to read the element with the specified key from the cache. If the 688 * value_size is too small, it will be filled with the proper number, and 689 * the user will need to call cache_read again with the value buffer, that 690 * is large enough. 691 * Function returns 0 on success, -1 on error, and -2 if the value_size is too 692 * small. 693 */ 694 int 695 cache_read(struct cache_entry_ *entry, const char *key, size_t key_size, 696 char *value, size_t *value_size) 697 { 698 struct cache_common_entry_ *common_entry; 699 struct cache_ht_item_data_ item_data, *find_res; 700 struct cache_ht_item_ *item; 701 hashtable_index_t hash; 702 struct cache_policy_item_ *connected_item; 703 704 TRACE_IN(cache_read); 705 assert(entry != NULL); 706 assert(key != NULL); 707 assert(value_size != NULL); 708 assert(entry->params->entry_type == CET_COMMON); 709 710 common_entry = (struct cache_common_entry_ *)entry; 711 712 memset(&item_data, 0, sizeof(struct cache_ht_item_data_)); 713 /* can't avoid the cast here */ 714 item_data.key = (char *)key; 715 item_data.key_size = key_size; 716 717 hash = HASHTABLE_CALCULATE_HASH(cache_ht_, &common_entry->items, 718 &item_data); 719 assert(hash >= 0); 720 assert(hash < HASHTABLE_ENTRIES_COUNT(&common_entry->items)); 721 722 item = HASHTABLE_GET_ENTRY(&(common_entry->items), hash); 723 find_res = HASHTABLE_ENTRY_FIND(cache_ht_, item, &item_data); 724 if (find_res == NULL) { 725 TRACE_OUT(cache_read); 726 return (-1); 727 } 728 729 if ((common_entry->common_params.max_lifetime.tv_sec != 0) || 730 (common_entry->common_params.max_lifetime.tv_usec != 0)) { 731 732 if (find_res->fifo_policy_item->last_request_time.tv_sec - 733 find_res->fifo_policy_item->creation_time.tv_sec > 734 common_entry->common_params.max_lifetime.tv_sec) { 735 736 free(find_res->key); 737 free(find_res->value); 738 739 connected_item = 740 find_res->fifo_policy_item->connected_item; 741 if (connected_item != NULL) { 742 common_entry->policies[1]->remove_item_func( 743 common_entry->policies[1], 744 connected_item); 745 common_entry->policies[1]->destroy_item_func( 746 connected_item); 747 } 748 749 common_entry->policies[0]->remove_item_func( 750 common_entry->policies[0], 751 find_res->fifo_policy_item); 752 common_entry->policies[0]->destroy_item_func( 753 find_res->fifo_policy_item); 754 755 HASHTABLE_ENTRY_REMOVE(cache_ht_, item, find_res); 756 --common_entry->items_size; 757 } 758 } 759 760 if ((*value_size < find_res->value_size) || (value == NULL)) { 761 *value_size = find_res->value_size; 762 TRACE_OUT(cache_read); 763 return (-2); 764 } 765 766 *value_size = find_res->value_size; 767 memcpy(value, find_res->value, find_res->value_size); 768 769 ++find_res->fifo_policy_item->request_count; 770 common_entry->get_time_func( 771 &find_res->fifo_policy_item->last_request_time); 772 common_entry->policies[0]->update_item_func(common_entry->policies[0], 773 find_res->fifo_policy_item); 774 775 if (find_res->fifo_policy_item->connected_item != NULL) { 776 connected_item = find_res->fifo_policy_item->connected_item; 777 memcpy(&connected_item->last_request_time, 778 &find_res->fifo_policy_item->last_request_time, 779 sizeof(struct timeval)); 780 connected_item->request_count = 781 find_res->fifo_policy_item->request_count; 782 783 common_entry->policies[1]->update_item_func( 784 common_entry->policies[1], connected_item); 785 } 786 787 TRACE_OUT(cache_read); 788 return (0); 789 } 790 791 /* 792 * Writes the value with the specified key into the cache entry. 793 * Functions returns 0 on success, and -1 on error. 794 */ 795 int 796 cache_write(struct cache_entry_ *entry, const char *key, size_t key_size, 797 char const *value, size_t value_size) 798 { 799 struct cache_common_entry_ *common_entry; 800 struct cache_ht_item_data_ item_data, *find_res; 801 struct cache_ht_item_ *item; 802 hashtable_index_t hash; 803 804 struct cache_policy_ *policy, *connected_policy; 805 struct cache_policy_item_ *policy_item; 806 struct cache_policy_item_ *connected_policy_item; 807 808 TRACE_IN(cache_write); 809 assert(entry != NULL); 810 assert(key != NULL); 811 assert(value != NULL); 812 assert(entry->params->entry_type == CET_COMMON); 813 814 common_entry = (struct cache_common_entry_ *)entry; 815 816 memset(&item_data, 0, sizeof(struct cache_ht_item_data_)); 817 /* can't avoid the cast here */ 818 item_data.key = (char *)key; 819 item_data.key_size = key_size; 820 821 hash = HASHTABLE_CALCULATE_HASH(cache_ht_, &common_entry->items, 822 &item_data); 823 assert(hash >= 0); 824 assert(hash < HASHTABLE_ENTRIES_COUNT(&common_entry->items)); 825 826 item = HASHTABLE_GET_ENTRY(&(common_entry->items), hash); 827 find_res = HASHTABLE_ENTRY_FIND(cache_ht_, item, &item_data); 828 if (find_res != NULL) { 829 TRACE_OUT(cache_write); 830 return (-1); 831 } 832 833 item_data.key = (char *)malloc(key_size); 834 memcpy(item_data.key, key, key_size); 835 836 item_data.value = (char *)malloc(value_size); 837 assert(item_data.value != NULL); 838 839 memcpy(item_data.value, value, value_size); 840 item_data.value_size = value_size; 841 842 policy_item = common_entry->policies[0]->create_item_func(); 843 policy_item->key = item_data.key; 844 policy_item->key_size = item_data.key_size; 845 common_entry->get_time_func(&policy_item->creation_time); 846 847 if (common_entry->policies_size > 1) { 848 connected_policy_item = 849 common_entry->policies[1]->create_item_func(); 850 memcpy(&connected_policy_item->creation_time, 851 &policy_item->creation_time, 852 sizeof(struct timeval)); 853 connected_policy_item->key = policy_item->key; 854 connected_policy_item->key_size = policy_item->key_size; 855 856 connected_policy_item->connected_item = policy_item; 857 policy_item->connected_item = connected_policy_item; 858 } 859 860 item_data.fifo_policy_item = policy_item; 861 862 common_entry->policies[0]->add_item_func(common_entry->policies[0], 863 policy_item); 864 if (common_entry->policies_size > 1) 865 common_entry->policies[1]->add_item_func( 866 common_entry->policies[1], connected_policy_item); 867 868 HASHTABLE_ENTRY_STORE(cache_ht_, item, &item_data); 869 ++common_entry->items_size; 870 871 if ((common_entry->common_params.max_elemsize != 0) && 872 (common_entry->items_size > 873 common_entry->common_params.max_elemsize)) { 874 if (common_entry->policies_size > 1) { 875 policy = common_entry->policies[1]; 876 connected_policy = common_entry->policies[0]; 877 } else { 878 policy = common_entry->policies[0]; 879 connected_policy = NULL; 880 } 881 882 flush_cache_policy(common_entry, policy, connected_policy, 883 cache_elemsize_common_continue_func); 884 } 885 886 TRACE_OUT(cache_write); 887 return (0); 888 } 889 890 /* 891 * Initializes the write session for the specified multipart entry. This 892 * session then should be filled with data either committed or abandoned by 893 * using close_cache_mp_write_session or abandon_cache_mp_write_session 894 * respectively. 895 * Returns NULL on errors (when there are too many opened write sessions for 896 * the entry). 897 */ 898 struct cache_mp_write_session_ * 899 open_cache_mp_write_session(struct cache_entry_ *entry) 900 { 901 struct cache_mp_entry_ *mp_entry; 902 struct cache_mp_write_session_ *retval; 903 904 TRACE_IN(open_cache_mp_write_session); 905 assert(entry != NULL); 906 assert(entry->params->entry_type == CET_MULTIPART); 907 mp_entry = (struct cache_mp_entry_ *)entry; 908 909 if ((mp_entry->mp_params.max_sessions > 0) && 910 (mp_entry->ws_size == mp_entry->mp_params.max_sessions)) { 911 TRACE_OUT(open_cache_mp_write_session); 912 return (NULL); 913 } 914 915 retval = (struct cache_mp_write_session_ *)calloc(1, 916 sizeof(struct cache_mp_write_session_)); 917 assert(retval != NULL); 918 919 TAILQ_INIT(&retval->items); 920 retval->parent_entry = mp_entry; 921 922 TAILQ_INSERT_HEAD(&mp_entry->ws_head, retval, entries); 923 ++mp_entry->ws_size; 924 925 TRACE_OUT(open_cache_mp_write_session); 926 return (retval); 927 } 928 929 /* 930 * Writes data to the specified session. Return 0 on success and -1 on errors 931 * (when write session size limit is exceeded). 932 */ 933 int 934 cache_mp_write(struct cache_mp_write_session_ *ws, char *data, 935 size_t data_size) 936 { 937 struct cache_mp_data_item_ *new_item; 938 939 TRACE_IN(cache_mp_write); 940 assert(ws != NULL); 941 assert(ws->parent_entry != NULL); 942 assert(ws->parent_entry->params->entry_type == CET_MULTIPART); 943 944 if ((ws->parent_entry->mp_params.max_elemsize > 0) && 945 (ws->parent_entry->mp_params.max_elemsize == ws->items_size)) { 946 TRACE_OUT(cache_mp_write); 947 return (-1); 948 } 949 950 new_item = (struct cache_mp_data_item_ *)calloc(1, 951 sizeof(struct cache_mp_data_item_)); 952 assert(new_item != NULL); 953 954 new_item->value = (char *)malloc(data_size); 955 assert(new_item->value != NULL); 956 memcpy(new_item->value, data, data_size); 957 new_item->value_size = data_size; 958 959 TAILQ_INSERT_TAIL(&ws->items, new_item, entries); 960 ++ws->items_size; 961 962 TRACE_OUT(cache_mp_write); 963 return (0); 964 } 965 966 /* 967 * Abandons the write session and frees all the connected resources. 968 */ 969 void 970 abandon_cache_mp_write_session(struct cache_mp_write_session_ *ws) 971 { 972 973 TRACE_IN(abandon_cache_mp_write_session); 974 assert(ws != NULL); 975 assert(ws->parent_entry != NULL); 976 assert(ws->parent_entry->params->entry_type == CET_MULTIPART); 977 978 TAILQ_REMOVE(&ws->parent_entry->ws_head, ws, entries); 979 --ws->parent_entry->ws_size; 980 981 destroy_cache_mp_write_session(ws); 982 TRACE_OUT(abandon_cache_mp_write_session); 983 } 984 985 /* 986 * Commits the session to the entry, for which it was created. 987 */ 988 void 989 close_cache_mp_write_session(struct cache_mp_write_session_ *ws) 990 { 991 992 TRACE_IN(close_cache_mp_write_session); 993 assert(ws != NULL); 994 assert(ws->parent_entry != NULL); 995 assert(ws->parent_entry->params->entry_type == CET_MULTIPART); 996 997 TAILQ_REMOVE(&ws->parent_entry->ws_head, ws, entries); 998 --ws->parent_entry->ws_size; 999 1000 if (ws->parent_entry->completed_write_session == NULL) { 1001 /* 1002 * If there is no completed session yet, this will be the one 1003 */ 1004 ws->parent_entry->get_time_func( 1005 &ws->parent_entry->creation_time); 1006 ws->parent_entry->completed_write_session = ws; 1007 } else { 1008 /* 1009 * If there is a completed session, then we'll save our session 1010 * as a pending session. If there is already a pending session, 1011 * it would be destroyed. 1012 */ 1013 if (ws->parent_entry->pending_write_session != NULL) 1014 destroy_cache_mp_write_session( 1015 ws->parent_entry->pending_write_session); 1016 1017 ws->parent_entry->pending_write_session = ws; 1018 } 1019 TRACE_OUT(close_cache_mp_write_session); 1020 } 1021 1022 /* 1023 * Opens read session for the specified entry. Returns NULL on errors (when 1024 * there are no data in the entry, or the data are obsolete). 1025 */ 1026 struct cache_mp_read_session_ * 1027 open_cache_mp_read_session(struct cache_entry_ *entry) 1028 { 1029 struct cache_mp_entry_ *mp_entry; 1030 struct cache_mp_read_session_ *retval; 1031 1032 TRACE_IN(open_cache_mp_read_session); 1033 assert(entry != NULL); 1034 assert(entry->params->entry_type == CET_MULTIPART); 1035 mp_entry = (struct cache_mp_entry_ *)entry; 1036 1037 if (mp_entry->completed_write_session == NULL) { 1038 TRACE_OUT(open_cache_mp_read_session); 1039 return (NULL); 1040 } 1041 1042 if ((mp_entry->mp_params.max_lifetime.tv_sec != 0) 1043 || (mp_entry->mp_params.max_lifetime.tv_usec != 0)) { 1044 if (mp_entry->last_request_time.tv_sec - 1045 mp_entry->last_request_time.tv_sec > 1046 mp_entry->mp_params.max_lifetime.tv_sec) { 1047 flush_cache_entry(entry); 1048 TRACE_OUT(open_cache_mp_read_session); 1049 return (NULL); 1050 } 1051 } 1052 1053 retval = (struct cache_mp_read_session_ *)calloc(1, 1054 sizeof(struct cache_mp_read_session_)); 1055 assert(retval != NULL); 1056 1057 retval->parent_entry = mp_entry; 1058 retval->current_item = TAILQ_FIRST( 1059 &mp_entry->completed_write_session->items); 1060 1061 TAILQ_INSERT_HEAD(&mp_entry->rs_head, retval, entries); 1062 ++mp_entry->rs_size; 1063 1064 mp_entry->get_time_func(&mp_entry->last_request_time); 1065 TRACE_OUT(open_cache_mp_read_session); 1066 return (retval); 1067 } 1068 1069 /* 1070 * Reads the data from the read session - step by step. 1071 * Returns 0 on success, -1 on error (when there are no more data), and -2 if 1072 * the data_size is too small. In the last case, data_size would be filled 1073 * the proper value. 1074 */ 1075 int 1076 cache_mp_read(struct cache_mp_read_session_ *rs, char *data, size_t *data_size) 1077 { 1078 1079 TRACE_IN(cache_mp_read); 1080 assert(rs != NULL); 1081 1082 if (rs->current_item == NULL) { 1083 TRACE_OUT(cache_mp_read); 1084 return (-1); 1085 } 1086 1087 if (rs->current_item->value_size > *data_size) { 1088 *data_size = rs->current_item->value_size; 1089 if (data == NULL) { 1090 TRACE_OUT(cache_mp_read); 1091 return (0); 1092 } 1093 1094 TRACE_OUT(cache_mp_read); 1095 return (-2); 1096 } 1097 1098 *data_size = rs->current_item->value_size; 1099 memcpy(data, rs->current_item->value, rs->current_item->value_size); 1100 rs->current_item = TAILQ_NEXT(rs->current_item, entries); 1101 1102 TRACE_OUT(cache_mp_read); 1103 return (0); 1104 } 1105 1106 /* 1107 * Closes the read session. If there are no more read sessions and there is 1108 * a pending write session, it will be committed and old 1109 * completed_write_session will be destroyed. 1110 */ 1111 void 1112 close_cache_mp_read_session(struct cache_mp_read_session_ *rs) 1113 { 1114 1115 TRACE_IN(close_cache_mp_read_session); 1116 assert(rs != NULL); 1117 assert(rs->parent_entry != NULL); 1118 1119 TAILQ_REMOVE(&rs->parent_entry->rs_head, rs, entries); 1120 --rs->parent_entry->rs_size; 1121 1122 if ((rs->parent_entry->rs_size == 0) && 1123 (rs->parent_entry->pending_write_session != NULL)) { 1124 destroy_cache_mp_write_session( 1125 rs->parent_entry->completed_write_session); 1126 rs->parent_entry->completed_write_session = 1127 rs->parent_entry->pending_write_session; 1128 rs->parent_entry->pending_write_session = NULL; 1129 } 1130 1131 destroy_cache_mp_read_session(rs); 1132 TRACE_OUT(close_cache_mp_read_session); 1133 } 1134 1135 int 1136 transform_cache_entry(struct cache_entry_ *entry, 1137 enum cache_transformation_t transformation) 1138 { 1139 1140 TRACE_IN(transform_cache_entry); 1141 switch (transformation) { 1142 case CTT_CLEAR: 1143 clear_cache_entry(entry); 1144 TRACE_OUT(transform_cache_entry); 1145 return (0); 1146 case CTT_FLUSH: 1147 flush_cache_entry(entry); 1148 TRACE_OUT(transform_cache_entry); 1149 return (0); 1150 default: 1151 TRACE_OUT(transform_cache_entry); 1152 return (-1); 1153 } 1154 } 1155 1156 int 1157 transform_cache_entry_part(struct cache_entry_ *entry, 1158 enum cache_transformation_t transformation, const char *key_part, 1159 size_t key_part_size, enum part_position_t part_position) 1160 { 1161 struct cache_common_entry_ *common_entry; 1162 struct cache_ht_item_ *ht_item; 1163 struct cache_ht_item_data_ *ht_item_data, ht_key; 1164 1165 struct cache_policy_item_ *item, *connected_item; 1166 1167 TRACE_IN(transform_cache_entry_part); 1168 if (entry->params->entry_type != CET_COMMON) { 1169 TRACE_OUT(transform_cache_entry_part); 1170 return (-1); 1171 } 1172 1173 if (transformation != CTT_CLEAR) { 1174 TRACE_OUT(transform_cache_entry_part); 1175 return (-1); 1176 } 1177 1178 memset(&ht_key, 0, sizeof(struct cache_ht_item_data_)); 1179 ht_key.key = (char *)key_part; /* can't avoid casting here */ 1180 ht_key.key_size = key_part_size; 1181 1182 common_entry = (struct cache_common_entry_ *)entry; 1183 HASHTABLE_FOREACH(&(common_entry->items), ht_item) { 1184 do { 1185 ht_item_data = HASHTABLE_ENTRY_FIND_SPECIAL(cache_ht_, 1186 ht_item, &ht_key, 1187 ht_items_fixed_size_left_cmp_func); 1188 1189 if (ht_item_data != NULL) { 1190 item = ht_item_data->fifo_policy_item; 1191 connected_item = item->connected_item; 1192 1193 common_entry->policies[0]->remove_item_func( 1194 common_entry->policies[0], 1195 item); 1196 1197 free(ht_item_data->key); 1198 free(ht_item_data->value); 1199 HASHTABLE_ENTRY_REMOVE(cache_ht_, ht_item, 1200 ht_item_data); 1201 --common_entry->items_size; 1202 1203 common_entry->policies[0]->destroy_item_func( 1204 item); 1205 if (common_entry->policies_size == 2) { 1206 common_entry->policies[1]->remove_item_func( 1207 common_entry->policies[1], 1208 connected_item); 1209 common_entry->policies[1]->destroy_item_func( 1210 connected_item); 1211 } 1212 } 1213 } while (ht_item_data != NULL); 1214 } 1215 1216 TRACE_OUT(transform_cache_entry_part); 1217 return (0); 1218 } 1219