src/store.cc

   1
   2 /*
   3  * DEBUG: section 20    Storage Manager
   4  * AUTHOR: Harvest Derived
   5  *
   6  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   7  * ----------------------------------------------------------
   8  *
   9  *  Squid is the result of efforts by numerous individuals from
  10  *  the Internet community; see the CONTRIBUTORS file for full
  11  *  details.   Many organizations have provided support for Squid's
  12  *  development; see the SPONSORS file for full details.  Squid is
  13  *  Copyrighted (C) 2001 by the Regents of the University of
  14  *  California; see the COPYRIGHT file for full details.  Squid
  15  *  incorporates software developed and/or copyrighted by other
  16  *  sources; see the CREDITS file for full details.
  17  *
  18  *  This program is free software; you can redistribute it and/or modify
  19  *  it under the terms of the GNU General Public License as published by
  20  *  the Free Software Foundation; either version 2 of the License, or
  21  *  (at your option) any later version.
  22  *
  23  *  This program is distributed in the hope that it will be useful,
  24  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *  GNU General Public License for more details.
  27  *
  28  *  You should have received a copy of the GNU General Public License
  29  *  along with this program; if not, write to the Free Software
  30  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  31  *
  32  */
  33
  34 #include "squid.h"
  35 #include "CacheDigest.h"
  36 #include "CacheManager.h"
  37 #include "comm/Connection.h"
  38 #include "ETag.h"
  39 #include "event.h"
  40 #include "fde.h"
  41 #include "globals.h"
  42 #include "http.h"
  43 #include "HttpReply.h"
  44 #include "HttpRequest.h"
  45 #include "mem_node.h"
  46 #include "MemObject.h"
  47 #include "mgr/Registration.h"
  48 #include "mgr/StoreIoAction.h"
  49 #include "profiler/Profiler.h"
  50 #include "repl_modules.h"
  51 #include "RequestFlags.h"
  52 #include "SquidConfig.h"
  53 #include "SquidTime.h"
  54 #include "Stack.h"
  55 #include "StatCounters.h"
  56 #include "stmem.h"
  57 #include "store_digest.h"
  58 #include "store_key_md5.h"
  59 #include "store_key_md5.h"
  60 #include "store_log.h"
  61 #include "store_rebuild.h"
  62 #include "Store.h"
  63 #include "StoreClient.h"
  64 #include "StoreIOState.h"
  65 #include "StoreMeta.h"
  66 #include "StrList.h"
  67 #include "swap_log_op.h"
  68 #include "SwapDir.h"
  69 #include "tools.h"
  70 #if USE_DELAY_POOLS
  71 #include "DelayPools.h"
  72 #endif
  73 #if HAVE_LIMITS_H
  74 #include <limits.h>
  75 #endif
  76
  77 #define REBUILD_TIMESTAMP_DELTA_MAX 2
  78
  79 #define STORE_IN_MEM_BUCKETS            (229)
  80
  81 /** \todo Convert these string constants to enum string-arrays generated */
  82
  83 const char *memStatusStr[] = {
  84     "NOT_IN_MEMORY",
  85     "IN_MEMORY"
  86 };
  87
  88 const char *pingStatusStr[] = {
  89     "PING_NONE",
  90     "PING_WAITING",
  91     "PING_DONE"
  92 };
  93
  94 const char *storeStatusStr[] = {
  95     "STORE_OK",
  96     "STORE_PENDING"
  97 };
  98
  99 const char *swapStatusStr[] = {
 100     "SWAPOUT_NONE",
 101     "SWAPOUT_WRITING",
 102     "SWAPOUT_DONE"
 103 };
 104
 105 /*
 106  * This defines an repl type
 107  */
 108
 109 typedef struct _storerepl_entry storerepl_entry_t;
 110
 111 struct _storerepl_entry {
 112     const char *typestr;
 113     REMOVALPOLICYCREATE *create;
 114 };
 115
 116 static storerepl_entry_t *storerepl_list = NULL;
 117
 118 /*
 119  * local function prototypes
 120  */
 121 static int getKeyCounter(void);
 122 static OBJH storeCheckCachableStats;
 123 static EVH storeLateRelease;
 124
 125 /*
 126  * local variables
 127  */
 128 static Stack<StoreEntry*> LateReleaseStack;
 129 MemAllocator *StoreEntry::pool = NULL;
 130
 131 StorePointer Store::CurrentRoot = NULL;
 132
 133 void
 134 Store::Root(Store * aRoot)
 135 {
 136     CurrentRoot = aRoot;
 137 }
 138
 139 void
 140 Store::Root(StorePointer aRoot)
 141 {
 142     Root(aRoot.getRaw());
 143 }
 144
 145 void
 146 Store::Stats(StoreEntry * output)
 147 {
 148     assert (output);
 149     Root().stat(*output);
 150 }
 151
 152 void
 153 Store::create()
 154 {}
 155
 156 void
 157 Store::diskFull()
 158 {}
 159
 160 void
 161 Store::sync()
 162 {}
 163
 164 void
 165 Store::unlink (StoreEntry &anEntry)
 166 {
 167     fatal("Store::unlink on invalid Store\n");
 168 }
 169
 170 void *
 171 StoreEntry::operator new (size_t bytecount)
 172 {
 173     assert (bytecount == sizeof (StoreEntry));
 174
 175     if (!pool) {
 176         pool = memPoolCreate ("StoreEntry", bytecount);
 177         pool->setChunkSize(2048 * 1024);
 178     }
 179
 180     return pool->alloc();
 181 }
 182
 183 void
 184 StoreEntry::operator delete (void *address)
 185 {
 186     pool->freeOne(address);
 187 }
 188
 189 void
 190 StoreEntry::makePublic()
 191 {
 192     /* This object can be cached for a long time */
 193
 194     if (!EBIT_TEST(flags, RELEASE_REQUEST))
 195         setPublicKey();
 196 }
 197
 198 void
 199 StoreEntry::makePrivate()
 200 {
 201     /* This object should never be cached at all */
 202     expireNow();
 203     releaseRequest(); /* delete object when not used */
 204 }
 205
 206 void
 207 StoreEntry::cacheNegatively()
 208 {
 209     /* This object may be negatively cached */
 210     negativeCache();
 211     makePublic();
 212 }
 213
 214 size_t
 215 StoreEntry::inUseCount()
 216 {
 217     if (!pool)
 218         return 0;
 219     return pool->getInUseCount();
 220 }
 221
 222 const char *
 223 StoreEntry::getMD5Text() const
 224 {
 225     return storeKeyText((const cache_key *)key);
 226 }
 227
 228 #include "comm.h"
 229
 230 void
 231 StoreEntry::DeferReader(void *theContext, CommRead const &aRead)
 232 {
 233     StoreEntry *anEntry = (StoreEntry *)theContext;
 234     anEntry->delayAwareRead(aRead.conn,
 235                             aRead.buf,
 236                             aRead.len,
 237                             aRead.callback);
 238 }
 239
 240 void
 241 StoreEntry::delayAwareRead(const Comm::ConnectionPointer &conn, char *buf, int len, AsyncCall::Pointer callback)
 242 {
 243     size_t amountToRead = bytesWanted(Range<size_t>(0, len));
 244     /* sketch: readdeferer* = getdeferer.
 245      * ->deferRead (fd, buf, len, callback, DelayAwareRead, this)
 246      */
 247
 248     if (amountToRead == 0) {
 249         assert (mem_obj);
 250         /* read ahead limit */
 251         /* Perhaps these two calls should both live in MemObject */
 252 #if USE_DELAY_POOLS
 253         if (!mem_obj->readAheadPolicyCanRead()) {
 254 #endif
 255             mem_obj->delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 256             return;
 257 #if USE_DELAY_POOLS
 258         }
 259
 260         /* delay id limit */
 261         mem_obj->mostBytesAllowed().delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 262         return;
 263
 264 #endif
 265
 266     }
 267
 268     if (fd_table[conn->fd].closing()) {
 269         // Readers must have closing callbacks if they want to be notified. No
 270         // readers appeared to care around 2009/12/14 as they skipped reading
 271         // for other reasons. Closing may already be true at the delyaAwareRead
 272         // call time or may happen while we wait after delayRead() above.
 273         debugs(20, 3, HERE << "wont read from closing " << conn << " for " <<
 274                callback);
 275         return; // the read callback will never be called
 276     }
 277
 278     comm_read(conn, buf, amountToRead, callback);
 279 }
 280
 281 size_t
 282 StoreEntry::bytesWanted (Range<size_t> const aRange, bool ignoreDelayPools) const
 283 {
 284     if (mem_obj == NULL)
 285         return aRange.end;
 286
 287 #if URL_CHECKSUM_DEBUG
 288
 289     mem_obj->checkUrlChecksum();
 290
 291 #endif
 292
 293     if (!mem_obj->readAheadPolicyCanRead())
 294         return 0;
 295
 296     return mem_obj->mostBytesWanted(aRange.end, ignoreDelayPools);
 297 }
 298
 299 bool
 300 StoreEntry::checkDeferRead(int fd) const
 301 {
 302     return (bytesWanted(Range<size_t>(0,INT_MAX)) == 0);
 303 }
 304
 305 void
 306 StoreEntry::setNoDelay (bool const newValue)
 307 {
 308     if (mem_obj)
 309         mem_obj->setNoDelay(newValue);
 310 }
 311
 312 // XXX: Type names mislead. STORE_DISK_CLIENT actually means that we should
 313 //      open swapin file, aggressively trim memory, and ignore read-ahead gap.
 314 //      It does not mean we will read from disk exclusively (or at all!).
 315 // XXX: May create STORE_DISK_CLIENT with no disk caching configured.
 316 // XXX: Collapsed clients cannot predict their type.
 317 store_client_t
 318 StoreEntry::storeClientType() const
 319 {
 320     /* The needed offset isn't in memory
 321      * XXX TODO: this is wrong for range requests
 322      * as the needed offset may *not* be 0, AND
 323      * offset 0 in the memory object is the HTTP headers.
 324      */
 325
 326     assert(mem_obj);
 327
 328     if (mem_obj->inmem_lo)
 329         return STORE_DISK_CLIENT;
 330
 331     if (EBIT_TEST(flags, ENTRY_ABORTED)) {
 332         /* I don't think we should be adding clients to aborted entries */
 333         debugs(20, DBG_IMPORTANT, "storeClientType: adding to ENTRY_ABORTED entry");
 334         return STORE_MEM_CLIENT;
 335     }
 336
 337     if (store_status == STORE_OK) {
 338         /* the object has completed. */
 339
 340         if (mem_obj->inmem_lo == 0 && !isEmpty()) {
 341             if (swap_status == SWAPOUT_DONE) {
 342                 debugs(20,7, HERE << mem_obj << " lo: " << mem_obj->inmem_lo << " hi: " << mem_obj->endOffset() << " size: " << mem_obj->object_sz);
 343                 if (mem_obj->endOffset() == mem_obj->object_sz) {
 344                     /* hot object fully swapped in (XXX: or swapped out?) */
 345                     return STORE_MEM_CLIENT;
 346                 }
 347             } else {
 348                 /* Memory-only, or currently being swapped out */
 349                 return STORE_MEM_CLIENT;
 350             }
 351         }
 352         return STORE_DISK_CLIENT;
 353     }
 354
 355     /* here and past, entry is STORE_PENDING */
 356     /*
 357      * If this is the first client, let it be the mem client
 358      */
 359     if (mem_obj->nclients == 1)
 360         return STORE_MEM_CLIENT;
 361
 362     /*
 363      * If there is no disk file to open yet, we must make this a
 364      * mem client.  If we can't open the swapin file before writing
 365      * to the client, there is no guarantee that we will be able
 366      * to open it later when we really need it.
 367      */
 368     if (swap_status == SWAPOUT_NONE)
 369         return STORE_MEM_CLIENT;
 370
 371     /*
 372      * otherwise, make subsequent clients read from disk so they
 373      * can not delay the first, and vice-versa.
 374      */
 375     return STORE_DISK_CLIENT;
 376 }
 377
 378 StoreEntry::StoreEntry() :
 379         mem_obj(NULL),
 380         timestamp(-1),
 381         lastref(-1),
 382         expires(-1),
 383         lastmod(-1),
 384         swap_file_sz(0),
 385         refcount(0),
 386         flags(0),
 387         swap_filen(-1),
 388         swap_dirn(-1),
 389         mem_status(NOT_IN_MEMORY),
 390         ping_status(PING_NONE),
 391         store_status(STORE_PENDING),
 392         swap_status(SWAPOUT_NONE),
 393         lock_count(0)
 394 {
 395     debugs(20, 3, HERE << "new StoreEntry " << this);
 396 }
 397
 398 StoreEntry::~StoreEntry()
 399 {
 400 }
 401
 402 #if USE_ADAPTATION
 403 void
 404 StoreEntry::deferProducer(const AsyncCall::Pointer &producer)
 405 {
 406     if (!deferredProducer)
 407         deferredProducer = producer;
 408     else
 409         debugs(20, 5, HERE << "Deferred producer call is allready set to: " <<
 410                *deferredProducer << ", requested call: " << *producer);
 411 }
 412
 413 void
 414 StoreEntry::kickProducer()
 415 {
 416     if (deferredProducer != NULL) {
 417         ScheduleCallHere(deferredProducer);
 418         deferredProducer = NULL;
 419     }
 420 }
 421 #endif
 422
 423 void
 424 StoreEntry::destroyMemObject()
 425 {
 426     debugs(20, 3, HERE << "destroyMemObject " << mem_obj);
 427
 428     if (MemObject *mem = mem_obj) {
 429         // Store::Root() is FATALly missing during shutdown
 430         if (mem->xitTable.index >= 0 && !shutting_down)
 431             Store::Root().transientsDisconnect(*mem);
 432         if (mem->memCache.index >= 0 && !shutting_down)
 433             Store::Root().memoryDisconnect(*this);
 434
 435         setMemStatus(NOT_IN_MEMORY);
 436         mem_obj = NULL;
 437         delete mem;
 438     }
 439 }
 440
 441 void
 442 destroyStoreEntry(void *data)
 443 {
 444     debugs(20, 3, HERE << "destroyStoreEntry: destroying " <<  data);
 445     StoreEntry *e = static_cast<StoreEntry *>(static_cast<hash_link *>(data));
 446     assert(e != NULL);
 447
 448     if (e == NullStoreEntry::getInstance())
 449         return;
 450
 451     // Store::Root() is FATALly missing during shutdown
 452     if (e->swap_filen >= 0 && !shutting_down) {
 453         SwapDir &sd = dynamic_cast<SwapDir&>(*e->store());
 454         sd.disconnect(*e);
 455     }
 456
 457     e->destroyMemObject();
 458
 459     e->hashDelete();
 460
 461     assert(e->key == NULL);
 462
 463     delete e;
 464 }
 465
 466 /* ----- INTERFACE BETWEEN STORAGE MANAGER AND HASH TABLE FUNCTIONS --------- */
 467
 468 void
 469 StoreEntry::hashInsert(const cache_key * someKey)
 470 {
 471     debugs(20, 3, "StoreEntry::hashInsert: Inserting Entry " << *this << " key '" << storeKeyText(someKey) << "'");
 472     key = storeKeyDup(someKey);
 473     hash_join(store_table, this);
 474 }
 475
 476 void
 477 StoreEntry::hashDelete()
 478 {
 479     hash_remove_link(store_table, this);
 480     storeKeyFree((const cache_key *)key);
 481     key = NULL;
 482 }
 483
 484 /* -------------------------------------------------------------------------- */
 485
 486 /* get rid of memory copy of the object */
 487 void
 488 StoreEntry::purgeMem()
 489 {
 490     if (mem_obj == NULL)
 491         return;
 492
 493     debugs(20, 3, "StoreEntry::purgeMem: Freeing memory-copy of " << getMD5Text());
 494
 495     Store::Root().memoryUnlink(*this);
 496
 497     if (swap_status != SWAPOUT_DONE)
 498         release();
 499 }
 500
 501 void
 502 StoreEntry::lock(const char *context)
 503 {
 504     ++lock_count;
 505     debugs(20, 3, context << " locked key " << getMD5Text() << ' ' << *this);
 506 }
 507
 508 void
 509 StoreEntry::touch() {
 510     lastref = squid_curtime;
 511     Store::Root().reference(*this);
 512 }
 513
 514 void
 515 StoreEntry::setReleaseFlag()
 516 {
 517     if (EBIT_TEST(flags, RELEASE_REQUEST))
 518         return;
 519
 520     debugs(20, 3, "StoreEntry::setReleaseFlag: '" << getMD5Text() << "'");
 521
 522     EBIT_SET(flags, RELEASE_REQUEST);
 523
 524     Store::Root().markForUnlink(*this);
 525 }
 526
 527 void
 528 StoreEntry::releaseRequest()
 529 {
 530     if (EBIT_TEST(flags, RELEASE_REQUEST))
 531         return;
 532
 533     setReleaseFlag(); // makes validToSend() false, preventing future hits
 534
 535     setPrivateKey();
 536 }
 537
 538 int
 539 StoreEntry::unlock(const char *context)
 540 {
 541     debugs(20, 3, (context ? context : "somebody") <<
 542            " unlocking key " << getMD5Text() << ' ' << *this);
 543     --lock_count;
 544
 545     if (lock_count)
 546         return (int) lock_count;
 547
 548     if (store_status == STORE_PENDING)
 549         setReleaseFlag();
 550
 551     assert(storePendingNClients(this) == 0);
 552
 553     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 554         this->release();
 555         return 0;
 556     }
 557
 558     if (EBIT_TEST(flags, KEY_PRIVATE))
 559         debugs(20, DBG_IMPORTANT, "WARNING: " << __FILE__ << ":" << __LINE__ << ": found KEY_PRIVATE");
 560
 561     Store::Root().handleIdleEntry(*this); // may delete us
 562     return 0;
 563 }
 564
 565 void
 566 StoreEntry::getPublicByRequestMethod  (StoreClient *aClient, HttpRequest * request, const HttpRequestMethod& method)
 567 {
 568     assert (aClient);
 569     StoreEntry *result = storeGetPublicByRequestMethod( request, method);
 570
 571     if (!result)
 572         aClient->created (NullStoreEntry::getInstance());
 573     else
 574         aClient->created (result);
 575 }
 576
 577 void
 578 StoreEntry::getPublicByRequest (StoreClient *aClient, HttpRequest * request)
 579 {
 580     assert (aClient);
 581     StoreEntry *result = storeGetPublicByRequest (request);
 582
 583     if (!result)
 584         result = NullStoreEntry::getInstance();
 585
 586     aClient->created (result);
 587 }
 588
 589 void
 590 StoreEntry::getPublic (StoreClient *aClient, const char *uri, const HttpRequestMethod& method)
 591 {
 592     assert (aClient);
 593     StoreEntry *result = storeGetPublic (uri, method);
 594
 595     if (!result)
 596         result = NullStoreEntry::getInstance();
 597
 598     aClient->created (result);
 599 }
 600
 601 StoreEntry *
 602 storeGetPublic(const char *uri, const HttpRequestMethod& method)
 603 {
 604     return Store::Root().get(storeKeyPublic(uri, method));
 605 }
 606
 607 StoreEntry *
 608 storeGetPublicByRequestMethod(HttpRequest * req, const HttpRequestMethod& method)
 609 {
 610     return Store::Root().get(storeKeyPublicByRequestMethod(req, method));
 611 }
 612
 613 StoreEntry *
 614 storeGetPublicByRequest(HttpRequest * req)
 615 {
 616     StoreEntry *e = storeGetPublicByRequestMethod(req, req->method);
 617
 618     if (e == NULL && req->method == Http::METHOD_HEAD)
 619         /* We can generate a HEAD reply from a cached GET object */
 620         e = storeGetPublicByRequestMethod(req, Http::METHOD_GET);
 621
 622     return e;
 623 }
 624
 625 static int
 626 getKeyCounter(void)
 627 {
 628     static int key_counter = 0;
 629
 630     if (++key_counter < 0)
 631         key_counter = 1;
 632
 633     return key_counter;
 634 }
 635
 636 /* RBC 20050104 AFAICT this should become simpler:
 637  * rather than reinserting with a special key it should be marked
 638  * as 'released' and then cleaned up when refcounting indicates.
 639  * the StoreHashIndex could well implement its 'released' in the
 640  * current manner.
 641  * Also, clean log writing should skip over ia,t
 642  * Otherwise, we need a 'remove from the index but not the store
 643  * concept'.
 644  */
 645 void
 646 StoreEntry::setPrivateKey()
 647 {
 648     const cache_key *newkey;
 649
 650     if (key && EBIT_TEST(flags, KEY_PRIVATE))
 651         return;                 /* is already private */
 652
 653     if (key) {
 654         setReleaseFlag(); // will markForUnlink(); all caches/workers will know
 655
 656         // TODO: move into SwapDir::markForUnlink() already called by Root()
 657         if (swap_filen > -1)
 658             storeDirSwapLog(this, SWAP_LOG_DEL);
 659
 660         hashDelete();
 661     }
 662
 663     if (mem_obj && mem_obj->hasUris()) {
 664         mem_obj->id = getKeyCounter();
 665         newkey = storeKeyPrivate(mem_obj->storeId(), mem_obj->method, mem_obj->id);
 666     } else {
 667         newkey = storeKeyPrivate("JUNK", Http::METHOD_NONE, getKeyCounter());
 668     }
 669
 670     assert(hash_lookup(store_table, newkey) == NULL);
 671     EBIT_SET(flags, KEY_PRIVATE);
 672     hashInsert(newkey);
 673 }
 674
 675 void
 676 StoreEntry::setPublicKey()
 677 {
 678     const cache_key *newkey;
 679
 680     if (key && !EBIT_TEST(flags, KEY_PRIVATE))
 681         return;                 /* is already public */
 682
 683     assert(mem_obj);
 684
 685     /*
 686      * We can't make RELEASE_REQUEST objects public.  Depending on
 687      * when RELEASE_REQUEST gets set, we might not be swapping out
 688      * the object.  If we're not swapping out, then subsequent
 689      * store clients won't be able to access object data which has
 690      * been freed from memory.
 691      *
 692      * If RELEASE_REQUEST is set, setPublicKey() should not be called.
 693      */
 694 #if MORE_DEBUG_OUTPUT
 695
 696     if (EBIT_TEST(flags, RELEASE_REQUEST))
 697         debugs(20, DBG_IMPORTANT, "assertion failed: RELEASE key " << key << ", url " << mem_obj->url);
 698
 699 #endif
 700
 701     assert(!EBIT_TEST(flags, RELEASE_REQUEST));
 702
 703     if (mem_obj->request) {
 704         HttpRequest *request = mem_obj->request;
 705
 706         if (!mem_obj->vary_headers) {
 707             /* First handle the case where the object no longer varies */
 708             safe_free(request->vary_headers);
 709         } else {
 710             if (request->vary_headers && strcmp(request->vary_headers, mem_obj->vary_headers) != 0) {
 711                 /* Oops.. the variance has changed. Kill the base object
 712                  * to record the new variance key
 713                  */
 714                 safe_free(request->vary_headers);       /* free old "bad" variance key */
 715                 if (StoreEntry *pe = storeGetPublic(mem_obj->storeId(), mem_obj->method))
 716                     pe->release();
 717             }
 718
 719             /* Make sure the request knows the variance status */
 720             if (!request->vary_headers) {
 721                 const char *vary = httpMakeVaryMark(request, mem_obj->getReply());
 722
 723                 if (vary)
 724                     request->vary_headers = xstrdup(vary);
 725             }
 726         }
 727
 728         // TODO: storeGetPublic() calls below may create unlocked entries.
 729         // We should add/use storeHas() API or lock/unlock those entries.
 730         if (mem_obj->vary_headers && !storeGetPublic(mem_obj->storeId(), mem_obj->method)) {
 731             /* Create "vary" base object */
 732             String vary;
 733             StoreEntry *pe = storeCreateEntry(mem_obj->storeId(), mem_obj->logUri(), request->flags, request->method);
 734             /* We are allowed to do this typecast */
 735             HttpReply *rep = new HttpReply;
 736             rep->setHeaders(Http::scOkay, "Internal marker object", "x-squid-internal/vary", -1, -1, squid_curtime + 100000);
 737             vary = mem_obj->getReply()->header.getList(HDR_VARY);
 738
 739             if (vary.size()) {
 740                 /* Again, we own this structure layout */
 741                 rep->header.putStr(HDR_VARY, vary.termedBuf());
 742                 vary.clean();
 743             }
 744
 745 #if X_ACCELERATOR_VARY
 746             vary = mem_obj->getReply()->header.getList(HDR_X_ACCELERATOR_VARY);
 747
 748             if (vary.defined()) {
 749                 /* Again, we own this structure layout */
 750                 rep->header.putStr(HDR_X_ACCELERATOR_VARY, vary.termedBuf());
 751                 vary.clean();
 752             }
 753
 754 #endif
 755             pe->replaceHttpReply(rep);
 756
 757             pe->timestampsSet();
 758
 759             pe->makePublic();
 760
 761             pe->complete();
 762
 763             pe->unlock("StoreEntry::setPublicKey+Vary");
 764         }
 765
 766         newkey = storeKeyPublicByRequest(mem_obj->request);
 767     } else
 768         newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 769
 770     if (StoreEntry *e2 = (StoreEntry *)hash_lookup(store_table, newkey)) {
 771         debugs(20, 3, "Making old " << *e2 << " private.");
 772         e2->setPrivateKey();
 773         e2->release();
 774
 775         if (mem_obj->request)
 776             newkey = storeKeyPublicByRequest(mem_obj->request);
 777         else
 778             newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 779     }
 780
 781     if (key)
 782         hashDelete();
 783
 784     EBIT_CLR(flags, KEY_PRIVATE);
 785
 786     hashInsert(newkey);
 787
 788     if (swap_filen > -1)
 789         storeDirSwapLog(this, SWAP_LOG_ADD);
 790 }
 791
 792 StoreEntry *
 793 storeCreatePureEntry(const char *url, const char *log_url, const RequestFlags &flags, const HttpRequestMethod& method)
 794 {
 795     StoreEntry *e = NULL;
 796     debugs(20, 3, "storeCreateEntry: '" << url << "'");
 797
 798     e = new StoreEntry();
 799     e->makeMemObject();
 800     e->mem_obj->setUris(url, log_url, method);
 801
 802     if (flags.cachable) {
 803         EBIT_CLR(e->flags, RELEASE_REQUEST);
 804     } else {
 805         e->releaseRequest();
 806     }
 807
 808     e->store_status = STORE_PENDING;
 809     e->refcount = 0;
 810     e->lastref = squid_curtime;
 811     e->timestamp = -1;          /* set in StoreEntry::timestampsSet() */
 812     e->ping_status = PING_NONE;
 813     EBIT_SET(e->flags, ENTRY_VALIDATED);
 814     return e;
 815 }
 816
 817 StoreEntry *
 818 storeCreateEntry(const char *url, const char *logUrl, const RequestFlags &flags, const HttpRequestMethod& method)
 819 {
 820     StoreEntry *e = storeCreatePureEntry(url, logUrl, flags, method);
 821     e->lock("storeCreateEntry");
 822
 823     if (neighbors_do_private_keys || !flags.hierarchical)
 824         e->setPrivateKey();
 825     else
 826         e->setPublicKey();
 827
 828     return e;
 829 }
 830
 831 /* Mark object as expired */
 832 void
 833 StoreEntry::expireNow()
 834 {
 835     debugs(20, 3, "StoreEntry::expireNow: '" << getMD5Text() << "'");
 836     expires = squid_curtime;
 837 }
 838
 839 void
 840 StoreEntry::write (StoreIOBuffer writeBuffer)
 841 {
 842     assert(mem_obj != NULL);
 843     /* This assert will change when we teach the store to update */
 844     PROF_start(StoreEntry_write);
 845     assert(store_status == STORE_PENDING);
 846
 847     // XXX: caller uses content offset, but we also store headers
 848     if (const HttpReply *reply = mem_obj->getReply())
 849         writeBuffer.offset += reply->hdr_sz;
 850
 851     debugs(20, 5, "storeWrite: writing " << writeBuffer.length << " bytes for '" << getMD5Text() << "'");
 852     PROF_stop(StoreEntry_write);
 853     storeGetMemSpace(writeBuffer.length);
 854     mem_obj->write(writeBuffer);
 855
 856     if (!EBIT_TEST(flags, DELAY_SENDING))
 857         invokeHandlers();
 858 }
 859
 860 /* Append incoming data from a primary server to an entry. */
 861 void
 862 StoreEntry::append(char const *buf, int len)
 863 {
 864     assert(mem_obj != NULL);
 865     assert(len >= 0);
 866     assert(store_status == STORE_PENDING);
 867
 868     StoreIOBuffer tempBuffer;
 869     tempBuffer.data = (char *)buf;
 870     tempBuffer.length = len;
 871     /*
 872      * XXX sigh, offset might be < 0 here, but it gets "corrected"
 873      * later.  This offset crap is such a mess.
 874      */
 875     tempBuffer.offset = mem_obj->endOffset() - (getReply() ? getReply()->hdr_sz : 0);
 876     write(tempBuffer);
 877 }
 878
 879 void
 880 storeAppendPrintf(StoreEntry * e, const char *fmt,...)
 881 {
 882     va_list args;
 883     va_start(args, fmt);
 884
 885     storeAppendVPrintf(e, fmt, args);
 886     va_end(args);
 887 }
 888
 889 /* used be storeAppendPrintf and Packer */
 890 void
 891 storeAppendVPrintf(StoreEntry * e, const char *fmt, va_list vargs)
 892 {
 893     LOCAL_ARRAY(char, buf, 4096);
 894     buf[0] = '\0';
 895     vsnprintf(buf, 4096, fmt, vargs);
 896     e->append(buf, strlen(buf));
 897 }
 898
 899 struct _store_check_cachable_hist {
 900
 901     struct {
 902         int non_get;
 903         int not_entry_cachable;
 904         int wrong_content_length;
 905         int negative_cached;
 906         int too_big;
 907         int too_small;
 908         int private_key;
 909         int too_many_open_files;
 910         int too_many_open_fds;
 911     } no;
 912
 913     struct {
 914         int Default;
 915     } yes;
 916 } store_check_cachable_hist;
 917
 918 int
 919 storeTooManyDiskFilesOpen(void)
 920 {
 921     if (Config.max_open_disk_fds == 0)
 922         return 0;
 923
 924     if (store_open_disk_fd > Config.max_open_disk_fds)
 925         return 1;
 926
 927     return 0;
 928 }
 929
 930 int
 931 StoreEntry::checkTooSmall()
 932 {
 933     if (EBIT_TEST(flags, ENTRY_SPECIAL))
 934         return 0;
 935
 936     if (STORE_OK == store_status)
 937         if (mem_obj->object_sz < 0 ||
 938                 mem_obj->object_sz < Config.Store.minObjectSize)
 939             return 1;
 940     if (getReply()->content_length > -1)
 941         if (getReply()->content_length < Config.Store.minObjectSize)
 942             return 1;
 943     return 0;
 944 }
 945
 946 // TODO: remove checks already performed by swapoutPossible()
 947 // TODO: move "too many open..." checks outside -- we are called too early/late
 948 int
 949 StoreEntry::checkCachable()
 950 {
 951 #if CACHE_ALL_METHODS
 952
 953     if (mem_obj->method != Http::METHOD_GET) {
 954         debugs(20, 2, "StoreEntry::checkCachable: NO: non-GET method");
 955         ++store_check_cachable_hist.no.non_get;
 956     } else
 957 #endif
 958         if (store_status == STORE_OK && EBIT_TEST(flags, ENTRY_BAD_LENGTH)) {
 959             debugs(20, 2, "StoreEntry::checkCachable: NO: wrong content-length");
 960             ++store_check_cachable_hist.no.wrong_content_length;
 961         } else if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 962             debugs(20, 2, "StoreEntry::checkCachable: NO: not cachable");
 963             ++store_check_cachable_hist.no.not_entry_cachable; // TODO: rename?
 964         } else if (EBIT_TEST(flags, ENTRY_NEGCACHED)) {
 965             debugs(20, 3, "StoreEntry::checkCachable: NO: negative cached");
 966             ++store_check_cachable_hist.no.negative_cached;
 967             return 0;           /* avoid release call below */
 968         } else if ((getReply()->content_length > 0 &&
 969                     getReply()->content_length > store_maxobjsize) ||
 970                    mem_obj->endOffset() > store_maxobjsize) {
 971             debugs(20, 2, "StoreEntry::checkCachable: NO: too big");
 972             ++store_check_cachable_hist.no.too_big;
 973         } else if (checkTooSmall()) {
 974             debugs(20, 2, "StoreEntry::checkCachable: NO: too small");
 975             ++store_check_cachable_hist.no.too_small;
 976         } else if (EBIT_TEST(flags, KEY_PRIVATE)) {
 977             debugs(20, 3, "StoreEntry::checkCachable: NO: private key");
 978             ++store_check_cachable_hist.no.private_key;
 979         } else if (swap_status != SWAPOUT_NONE) {
 980             /*
 981              * here we checked the swap_status because the remaining
 982              * cases are only relevant only if we haven't started swapping
 983              * out the object yet.
 984              */
 985             return 1;
 986         } else if (storeTooManyDiskFilesOpen()) {
 987             debugs(20, 2, "StoreEntry::checkCachable: NO: too many disk files open");
 988             ++store_check_cachable_hist.no.too_many_open_files;
 989         } else if (fdNFree() < RESERVED_FD) {
 990             debugs(20, 2, "StoreEntry::checkCachable: NO: too many FD's open");
 991             ++store_check_cachable_hist.no.too_many_open_fds;
 992         } else {
 993             ++store_check_cachable_hist.yes.Default;
 994             return 1;
 995         }
 996
 997     releaseRequest();
 998     return 0;
 999 }
1000
1001 void
1002 storeCheckCachableStats(StoreEntry *sentry)
1003 {
1004     storeAppendPrintf(sentry, "Category\t Count\n");
1005
1006 #if CACHE_ALL_METHODS
1007
1008     storeAppendPrintf(sentry, "no.non_get\t%d\n",
1009                       store_check_cachable_hist.no.non_get);
1010 #endif
1011
1012     storeAppendPrintf(sentry, "no.not_entry_cachable\t%d\n",
1013                       store_check_cachable_hist.no.not_entry_cachable);
1014     storeAppendPrintf(sentry, "no.wrong_content_length\t%d\n",
1015                       store_check_cachable_hist.no.wrong_content_length);
1016     storeAppendPrintf(sentry, "no.negative_cached\t%d\n",
1017                       store_check_cachable_hist.no.negative_cached);
1018     storeAppendPrintf(sentry, "no.too_big\t%d\n",
1019                       store_check_cachable_hist.no.too_big);
1020     storeAppendPrintf(sentry, "no.too_small\t%d\n",
1021                       store_check_cachable_hist.no.too_small);
1022     storeAppendPrintf(sentry, "no.private_key\t%d\n",
1023                       store_check_cachable_hist.no.private_key);
1024     storeAppendPrintf(sentry, "no.too_many_open_files\t%d\n",
1025                       store_check_cachable_hist.no.too_many_open_files);
1026     storeAppendPrintf(sentry, "no.too_many_open_fds\t%d\n",
1027                       store_check_cachable_hist.no.too_many_open_fds);
1028     storeAppendPrintf(sentry, "yes.default\t%d\n",
1029                       store_check_cachable_hist.yes.Default);
1030 }
1031
1032 void
1033 StoreEntry::complete()
1034 {
1035     debugs(20, 3, "storeComplete: '" << getMD5Text() << "'");
1036
1037     if (store_status != STORE_PENDING) {
1038         /*
1039          * if we're not STORE_PENDING, then probably we got aborted
1040          * and there should be NO clients on this entry
1041          */
1042         assert(EBIT_TEST(flags, ENTRY_ABORTED));
1043         assert(mem_obj->nclients == 0);
1044         return;
1045     }
1046
1047     /* This is suspect: mem obj offsets include the headers. do we adjust for that
1048      * in use of object_sz?
1049      */
1050     mem_obj->object_sz = mem_obj->endOffset();
1051
1052     store_status = STORE_OK;
1053
1054     assert(mem_status == NOT_IN_MEMORY);
1055
1056     if (!validLength()) {
1057         EBIT_SET(flags, ENTRY_BAD_LENGTH);
1058         releaseRequest();
1059     }
1060
1061 #if USE_CACHE_DIGESTS
1062     if (mem_obj->request)
1063         mem_obj->request->hier.store_complete_stop = current_time;
1064
1065 #endif
1066     /*
1067      * We used to call invokeHandlers, then storeSwapOut.  However,
1068      * Madhukar Reddy <myreddy@persistence.com> reported that
1069      * responses without content length would sometimes get released
1070      * in client_side, thinking that the response is incomplete.
1071      */
1072     invokeHandlers();
1073 }
1074
1075 /*
1076  * Someone wants to abort this transfer.  Set the reason in the
1077  * request structure, call the server-side callback and mark the
1078  * entry for releasing
1079  */
1080 void
1081 StoreEntry::abort()
1082 {
1083     ++statCounter.aborted_requests;
1084     assert(store_status == STORE_PENDING);
1085     assert(mem_obj != NULL);
1086     debugs(20, 6, "storeAbort: " << getMD5Text());
1087
1088     lock("StoreEntry::abort");         /* lock while aborting */
1089     negativeCache();
1090
1091     releaseRequest();
1092
1093     EBIT_SET(flags, ENTRY_ABORTED);
1094
1095     setMemStatus(NOT_IN_MEMORY);
1096
1097     store_status = STORE_OK;
1098
1099     /* Notify the server side */
1100
1101     /*
1102      * DPW 2007-05-07
1103      * Should we check abort.data for validity?
1104      */
1105     if (mem_obj->abort.callback) {
1106         if (!cbdataReferenceValid(mem_obj->abort.data))
1107             debugs(20, DBG_IMPORTANT,HERE << "queueing event when abort.data is not valid");
1108         eventAdd("mem_obj->abort.callback",
1109                  mem_obj->abort.callback,
1110                  mem_obj->abort.data,
1111                  0.0,
1112                  true);
1113         unregisterAbort();
1114     }
1115
1116     /* XXX Should we reverse these two, so that there is no
1117      * unneeded disk swapping triggered?
1118      */
1119     /* Notify the client side */
1120     invokeHandlers();
1121
1122     // abort swap out, invalidating what was created so far (release follows)
1123     swapOutFileClose(StoreIOState::writerGone);
1124
1125     unlock("StoreEntry::abort");       /* unlock */
1126 }
1127
1128 /**
1129  * Clear Memory storage to accommodate the given object len
1130  */
1131 void
1132 storeGetMemSpace(int size)
1133 {
1134     PROF_start(storeGetMemSpace);
1135     StoreEntry *e = NULL;
1136     int released = 0;
1137     static time_t last_check = 0;
1138     size_t pages_needed;
1139     RemovalPurgeWalker *walker;
1140
1141     if (squid_curtime == last_check) {
1142         PROF_stop(storeGetMemSpace);
1143         return;
1144     }
1145
1146     last_check = squid_curtime;
1147
1148     pages_needed = (size + SM_PAGE_SIZE-1) / SM_PAGE_SIZE;
1149
1150     if (mem_node::InUseCount() + pages_needed < store_pages_max) {
1151         PROF_stop(storeGetMemSpace);
1152         return;
1153     }
1154
1155     debugs(20, 2, "storeGetMemSpace: Starting, need " << pages_needed <<
1156            " pages");
1157
1158     /* XXX what to set as max_scan here? */
1159     walker = mem_policy->PurgeInit(mem_policy, 100000);
1160
1161     while ((e = walker->Next(walker))) {
1162         e->purgeMem();
1163         ++released;
1164
1165         if (mem_node::InUseCount() + pages_needed < store_pages_max)
1166             break;
1167     }
1168
1169     walker->Done(walker);
1170     debugs(20, 3, "storeGetMemSpace stats:");
1171     debugs(20, 3, "  " << std::setw(6) << hot_obj_count  << " HOT objects");
1172     debugs(20, 3, "  " << std::setw(6) << released  << " were released");
1173     PROF_stop(storeGetMemSpace);
1174 }
1175
1176 /* thunk through to Store::Root().maintain(). Note that this would be better still
1177  * if registered against the root store itself, but that requires more complex
1178  * update logic - bigger fish to fry first. Long term each store when
1179  * it becomes active will self register
1180  */
1181 void
1182 Store::Maintain(void *notused)
1183 {
1184     Store::Root().maintain();
1185
1186     /* Reregister a maintain event .. */
1187     eventAdd("MaintainSwapSpace", Maintain, NULL, 1.0, 1);
1188
1189 }
1190
1191 /* The maximum objects to scan for maintain storage space */
1192 #define MAINTAIN_MAX_SCAN       1024
1193 #define MAINTAIN_MAX_REMOVE     64
1194
1195 /*
1196  * This routine is to be called by main loop in main.c.
1197  * It removes expired objects on only one bucket for each time called.
1198  *
1199  * This should get called 1/s from main().
1200  */
1201 void
1202 StoreController::maintain()
1203 {
1204     static time_t last_warn_time = 0;
1205
1206     PROF_start(storeMaintainSwapSpace);
1207     swapDir->maintain();
1208
1209     /* this should be emitted by the oversize dir, not globally */
1210
1211     if (Store::Root().currentSize() > Store::Root().maxSize()) {
1212         if (squid_curtime - last_warn_time > 10) {
1213             debugs(20, DBG_CRITICAL, "WARNING: Disk space over limit: "
1214                    << Store::Root().currentSize() / 1024.0 << " KB > "
1215                    << (Store::Root().maxSize() >> 10) << " KB");
1216             last_warn_time = squid_curtime;
1217         }
1218     }
1219
1220     PROF_stop(storeMaintainSwapSpace);
1221 }
1222
1223 /* release an object from a cache */
1224 void
1225 StoreEntry::release()
1226 {
1227     PROF_start(storeRelease);
1228     debugs(20, 3, "releasing " << *this << ' ' << getMD5Text());
1229     /* If, for any reason we can't discard this object because of an
1230      * outstanding request, mark it for pending release */
1231
1232     if (locked()) {
1233         expireNow();
1234         debugs(20, 3, "storeRelease: Only setting RELEASE_REQUEST bit");
1235         releaseRequest();
1236         PROF_stop(storeRelease);
1237         return;
1238     }
1239
1240     Store::Root().memoryUnlink(*this);
1241
1242     if (StoreController::store_dirs_rebuilding && swap_filen > -1) {
1243         setPrivateKey();
1244
1245         if (swap_filen > -1) {
1246             /*
1247              * Fake a call to StoreEntry->lock()  When rebuilding is done,
1248              * we'll just call StoreEntry->unlock() on these.
1249              */
1250             lock("StoreEntry::release+rebuilding");
1251             setReleaseFlag();
1252             LateReleaseStack.push_back(this);
1253         } else {
1254             destroyStoreEntry(static_cast<hash_link *>(this));
1255             // "this" is no longer valid
1256         }
1257
1258         PROF_stop(storeRelease);
1259         return;
1260     }
1261
1262     storeLog(STORE_LOG_RELEASE, this);
1263
1264     if (swap_filen > -1) {
1265         // log before unlink() below clears swap_filen
1266         if (!EBIT_TEST(flags, KEY_PRIVATE))
1267             storeDirSwapLog(this, SWAP_LOG_DEL);
1268
1269         unlink();
1270     }
1271
1272     destroyStoreEntry(static_cast<hash_link *>(this));
1273     PROF_stop(storeRelease);
1274 }
1275
1276 static void
1277 storeLateRelease(void *unused)
1278 {
1279     StoreEntry *e;
1280     int i;
1281     static int n = 0;
1282
1283     if (StoreController::store_dirs_rebuilding) {
1284         eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1285         return;
1286     }
1287
1288     for (i = 0; i < 10; ++i) {
1289         e = LateReleaseStack.count ? LateReleaseStack.pop() : NULL;
1290
1291         if (e == NULL) {
1292             /* done! */
1293             debugs(20, DBG_IMPORTANT, "storeLateRelease: released " << n << " objects");
1294             return;
1295         }
1296
1297         e->unlock("storeLateRelease");
1298         ++n;
1299     }
1300
1301     eventAdd("storeLateRelease", storeLateRelease, NULL, 0.0, 1);
1302 }
1303
1304 /* return 1 if a store entry is locked */
1305 int
1306 StoreEntry::locked() const
1307 {
1308     if (lock_count)
1309         return 1;
1310
1311     /*
1312      * SPECIAL, PUBLIC entries should be "locked";
1313      * XXX: Their owner should lock them then instead of relying on this hack.
1314      */
1315     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1316         if (!EBIT_TEST(flags, KEY_PRIVATE))
1317             return 1;
1318
1319     return 0;
1320 }
1321
1322 bool
1323 StoreEntry::validLength() const
1324 {
1325     int64_t diff;
1326     const HttpReply *reply;
1327     assert(mem_obj != NULL);
1328     reply = getReply();
1329     debugs(20, 3, "storeEntryValidLength: Checking '" << getMD5Text() << "'");
1330     debugs(20, 5, "storeEntryValidLength:     object_len = " <<
1331            objectLen());
1332     debugs(20, 5, "storeEntryValidLength:         hdr_sz = " << reply->hdr_sz);
1333     debugs(20, 5, "storeEntryValidLength: content_length = " << reply->content_length);
1334
1335     if (reply->content_length < 0) {
1336         debugs(20, 5, "storeEntryValidLength: Unspecified content length: " << getMD5Text());
1337         return 1;
1338     }
1339
1340     if (reply->hdr_sz == 0) {
1341         debugs(20, 5, "storeEntryValidLength: Zero header size: " << getMD5Text());
1342         return 1;
1343     }
1344
1345     if (mem_obj->method == Http::METHOD_HEAD) {
1346         debugs(20, 5, "storeEntryValidLength: HEAD request: " << getMD5Text());
1347         return 1;
1348     }
1349
1350     if (reply->sline.status() == Http::scNotModified)
1351         return 1;
1352
1353     if (reply->sline.status() == Http::scNoContent)
1354         return 1;
1355
1356     diff = reply->hdr_sz + reply->content_length - objectLen();
1357
1358     if (diff == 0)
1359         return 1;
1360
1361     debugs(20, 3, "storeEntryValidLength: " << (diff < 0 ? -diff : diff)  << " bytes too " << (diff < 0 ? "big" : "small") <<"; '" << getMD5Text() << "'" );
1362
1363     return 0;
1364 }
1365
1366 static void
1367 storeRegisterWithCacheManager(void)
1368 {
1369     Mgr::RegisterAction("storedir", "Store Directory Stats", Store::Stats, 0, 1);
1370     Mgr::RegisterAction("store_io", "Store IO Interface Stats", &Mgr::StoreIoAction::Create, 0, 1);
1371     Mgr::RegisterAction("store_check_cachable_stats", "storeCheckCachable() Stats",
1372                         storeCheckCachableStats, 0, 1);
1373 }
1374
1375 void
1376 storeInit(void)
1377 {
1378     storeKeyInit();
1379     mem_policy = createRemovalPolicy(Config.memPolicy);
1380     storeDigestInit();
1381     storeLogOpen();
1382     eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1383     Store::Root().init();
1384     storeRebuildStart();
1385
1386     storeRegisterWithCacheManager();
1387 }
1388
1389 void
1390 storeConfigure(void)
1391 {
1392     store_swap_high = (long) (((float) Store::Root().maxSize() *
1393                                (float) Config.Swap.highWaterMark) / (float) 100);
1394     store_swap_low = (long) (((float) Store::Root().maxSize() *
1395                               (float) Config.Swap.lowWaterMark) / (float) 100);
1396     store_pages_max = Config.memMaxSize / sizeof(mem_node);
1397 }
1398
1399 bool
1400 StoreEntry::memoryCachable() const
1401 {
1402     if (mem_obj == NULL)
1403         return 0;
1404
1405     if (mem_obj->data_hdr.size() == 0)
1406         return 0;
1407
1408     if (mem_obj->inmem_lo != 0)
1409         return 0;
1410
1411     if (!Config.onoff.memory_cache_first && swap_status == SWAPOUT_DONE && refcount == 1)
1412         return 0;
1413
1414     return 1;
1415 }
1416
1417 int
1418 StoreEntry::checkNegativeHit() const
1419 {
1420     if (!EBIT_TEST(flags, ENTRY_NEGCACHED))
1421         return 0;
1422
1423     if (expires <= squid_curtime)
1424         return 0;
1425
1426     if (store_status != STORE_OK)
1427         return 0;
1428
1429     return 1;
1430 }
1431
1432 /**
1433  * Set object for negative caching.
1434  * Preserves any expiry information given by the server.
1435  * In absence of proper expiry info it will set to expire immediately,
1436  * or with HTTP-violations enabled the configured negative-TTL is observed
1437  */
1438 void
1439 StoreEntry::negativeCache()
1440 {
1441     // XXX: should make the default for expires 0 instead of -1
1442     //      so we can distinguish "Expires: -1" from nothing.
1443     if (expires <= 0)
1444 #if USE_HTTP_VIOLATIONS
1445         expires = squid_curtime + Config.negativeTtl;
1446 #else
1447         expires = squid_curtime;
1448 #endif
1449     EBIT_SET(flags, ENTRY_NEGCACHED);
1450 }
1451
1452 void
1453 storeFreeMemory(void)
1454 {
1455     Store::Root(NULL);
1456 #if USE_CACHE_DIGESTS
1457
1458     if (store_digest)
1459         cacheDigestDestroy(store_digest);
1460
1461 #endif
1462
1463     store_digest = NULL;
1464 }
1465
1466 int
1467 expiresMoreThan(time_t expires, time_t when)
1468 {
1469     if (expires < 0)            /* No Expires given */
1470         return 1;
1471
1472     return (expires > (squid_curtime + when));
1473 }
1474
1475 int
1476 StoreEntry::validToSend() const
1477 {
1478     if (EBIT_TEST(flags, RELEASE_REQUEST))
1479         return 0;
1480
1481     if (EBIT_TEST(flags, ENTRY_NEGCACHED))
1482         if (expires <= squid_curtime)
1483             return 0;
1484
1485     if (EBIT_TEST(flags, ENTRY_ABORTED))
1486         return 0;
1487
1488     // now check that the entry has a cache backing or is collapsed
1489     if (swap_filen > -1) // backed by a disk cache
1490         return 1;
1491
1492     if (swappingOut()) // will be backed by a disk cache
1493         return 1;
1494
1495     if (!mem_obj) // not backed by a memory cache and not collapsed
1496         return 0;
1497
1498     if (mem_obj->memCache.index >= 0) // backed by a shared memory cache
1499         return 0;
1500
1501     // StoreEntry::storeClientType() assumes DISK_CLIENT here, but there is no
1502     // disk cache backing so we should not rely on the store cache at all. This
1503     // is wrong for range requests that could feed off nibbled memory (XXX).
1504     if (mem_obj->inmem_lo) // in local memory cache, but got nibbled at
1505         return 0;
1506
1507     return 1;
1508 }
1509
1510 void
1511 StoreEntry::timestampsSet()
1512 {
1513     const HttpReply *reply = getReply();
1514     time_t served_date = reply->date;
1515     int age = reply->header.getInt(HDR_AGE);
1516     /* Compute the timestamp, mimicking RFC2616 section 13.2.3. */
1517     /* make sure that 0 <= served_date <= squid_curtime */
1518
1519     if (served_date < 0 || served_date > squid_curtime)
1520         served_date = squid_curtime;
1521
1522     /* Bug 1791:
1523      * If the returned Date: is more than 24 hours older than
1524      * the squid_curtime, then one of us needs to use NTP to set our
1525      * clock.  We'll pretend that our clock is right.
1526      */
1527     else if (served_date < (squid_curtime - 24 * 60 * 60) )
1528         served_date = squid_curtime;
1529
1530     /*
1531      * Compensate with Age header if origin server clock is ahead
1532      * of us and there is a cache in between us and the origin
1533      * server.  But DONT compensate if the age value is larger than
1534      * squid_curtime because it results in a negative served_date.
1535      */
1536     if (age > squid_curtime - served_date)
1537         if (squid_curtime > age)
1538             served_date = squid_curtime - age;
1539
1540     // compensate for Squid-to-server and server-to-Squid delays
1541     if (mem_obj && mem_obj->request) {
1542         const time_t request_sent =
1543             mem_obj->request->hier.peer_http_request_sent.tv_sec;
1544         if (0 < request_sent && request_sent < squid_curtime)
1545             served_date -= (squid_curtime - request_sent);
1546     }
1547
1548     if (reply->expires > 0 && reply->date > -1)
1549         expires = served_date + (reply->expires - reply->date);
1550     else
1551         expires = reply->expires;
1552
1553     lastmod = reply->last_modified;
1554
1555     timestamp = served_date;
1556 }
1557
1558 void
1559 StoreEntry::registerAbort(STABH * cb, void *data)
1560 {
1561     assert(mem_obj);
1562     assert(mem_obj->abort.callback == NULL);
1563     mem_obj->abort.callback = cb;
1564     mem_obj->abort.data = cbdataReference(data);
1565 }
1566
1567 void
1568 StoreEntry::unregisterAbort()
1569 {
1570     assert(mem_obj);
1571     if (mem_obj->abort.callback) {
1572         mem_obj->abort.callback = NULL;
1573         cbdataReferenceDone(mem_obj->abort.data);
1574     }
1575 }
1576
1577 void
1578 StoreEntry::dump(int l) const
1579 {
1580     debugs(20, l, "StoreEntry->key: " << getMD5Text());
1581     debugs(20, l, "StoreEntry->next: " << next);
1582     debugs(20, l, "StoreEntry->mem_obj: " << mem_obj);
1583     debugs(20, l, "StoreEntry->timestamp: " << timestamp);
1584     debugs(20, l, "StoreEntry->lastref: " << lastref);
1585     debugs(20, l, "StoreEntry->expires: " << expires);
1586     debugs(20, l, "StoreEntry->lastmod: " << lastmod);
1587     debugs(20, l, "StoreEntry->swap_file_sz: " << swap_file_sz);
1588     debugs(20, l, "StoreEntry->refcount: " << refcount);
1589     debugs(20, l, "StoreEntry->flags: " << storeEntryFlags(this));
1590     debugs(20, l, "StoreEntry->swap_dirn: " << swap_dirn);
1591     debugs(20, l, "StoreEntry->swap_filen: " << swap_filen);
1592     debugs(20, l, "StoreEntry->lock_count: " << lock_count);
1593     debugs(20, l, "StoreEntry->mem_status: " << mem_status);
1594     debugs(20, l, "StoreEntry->ping_status: " << ping_status);
1595     debugs(20, l, "StoreEntry->store_status: " << store_status);
1596     debugs(20, l, "StoreEntry->swap_status: " << swap_status);
1597 }
1598
1599 /*
1600  * NOTE, this function assumes only two mem states
1601  */
1602 void
1603 StoreEntry::setMemStatus(mem_status_t new_status)
1604 {
1605     if (new_status == mem_status)
1606         return;
1607
1608     // are we using a shared memory cache?
1609     if (Config.memShared && IamWorkerProcess()) {
1610         // This method was designed to update replacement policy, not to
1611         // actually purge something from the memory cache (TODO: rename?).
1612         // Shared memory cache does not have a policy that needs updates.
1613         mem_status = new_status;
1614         return;
1615     }
1616
1617     assert(mem_obj != NULL);
1618
1619     if (new_status == IN_MEMORY) {
1620         assert(mem_obj->inmem_lo == 0);
1621
1622         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1623             debugs(20, 4, "not inserting special " << *this << " into policy");
1624         } else {
1625             mem_policy->Add(mem_policy, this, &mem_obj->repl);
1626             debugs(20, 4, "inserted " << *this << " key: " << getMD5Text());
1627         }
1628
1629         ++hot_obj_count; // TODO: maintain for the shared hot cache as well
1630     } else {
1631         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1632             debugs(20, 4, "not removing special " << *this << " from policy");
1633         } else {
1634             mem_policy->Remove(mem_policy, this, &mem_obj->repl);
1635             debugs(20, 4, "removed " << *this);
1636         }
1637
1638         --hot_obj_count;
1639     }
1640
1641     mem_status = new_status;
1642 }
1643
1644 const char *
1645 StoreEntry::url() const
1646 {
1647     if (this == NULL)
1648         return "[null_entry]";
1649     else if (mem_obj == NULL)
1650         return "[null_mem_obj]";
1651     else
1652         return mem_obj->storeId();
1653 }
1654
1655 MemObject *
1656 StoreEntry::makeMemObject()
1657 {
1658     if (!mem_obj)
1659         mem_obj = new MemObject();
1660     return mem_obj;
1661 }
1662
1663 void
1664 StoreEntry::createMemObject(const char *aUrl, const char *aLogUrl, const HttpRequestMethod &aMethod)
1665 {
1666     makeMemObject();
1667     mem_obj->setUris(aUrl, aLogUrl, aMethod);
1668 }
1669
1670 /* this just sets DELAY_SENDING */
1671 void
1672 StoreEntry::buffer()
1673 {
1674     EBIT_SET(flags, DELAY_SENDING);
1675 }
1676
1677 /* this just clears DELAY_SENDING and Invokes the handlers */
1678 void
1679 StoreEntry::flush()
1680 {
1681     if (EBIT_TEST(flags, DELAY_SENDING)) {
1682         EBIT_CLR(flags, DELAY_SENDING);
1683         invokeHandlers();
1684     }
1685 }
1686
1687 int64_t
1688 StoreEntry::objectLen() const
1689 {
1690     assert(mem_obj != NULL);
1691     return mem_obj->object_sz;
1692 }
1693
1694 int64_t
1695 StoreEntry::contentLen() const
1696 {
1697     assert(mem_obj != NULL);
1698     assert(getReply() != NULL);
1699     return objectLen() - getReply()->hdr_sz;
1700 }
1701
1702 HttpReply const *
1703 StoreEntry::getReply () const
1704 {
1705     if (NULL == mem_obj)
1706         return NULL;
1707
1708     return mem_obj->getReply();
1709 }
1710
1711 void
1712 StoreEntry::reset()
1713 {
1714     assert (mem_obj);
1715     debugs(20, 3, "StoreEntry::reset: " << url());
1716     mem_obj->reset();
1717     HttpReply *rep = (HttpReply *) getReply();       // bypass const
1718     rep->reset();
1719     expires = lastmod = timestamp = -1;
1720 }
1721
1722 /*
1723  * storeFsInit
1724  *
1725  * This routine calls the SETUP routine for each fs type.
1726  * I don't know where the best place for this is, and I'm not going to shuffle
1727  * around large chunks of code right now (that can be done once its working.)
1728  */
1729 void
1730 storeFsInit(void)
1731 {
1732     storeReplSetup();
1733 }
1734
1735 /*
1736  * called to add another store removal policy module
1737  */
1738 void
1739 storeReplAdd(const char *type, REMOVALPOLICYCREATE * create)
1740 {
1741     int i;
1742
1743     /* find the number of currently known repl types */
1744     for (i = 0; storerepl_list && storerepl_list[i].typestr; ++i) {
1745         if (strcmp(storerepl_list[i].typestr, type) == 0) {
1746             debugs(20, DBG_IMPORTANT, "WARNING: Trying to load store replacement policy " << type << " twice.");
1747             return;
1748         }
1749     }
1750
1751     /* add the new type */
1752     storerepl_list = static_cast<storerepl_entry_t *>(xrealloc(storerepl_list, (i + 2) * sizeof(storerepl_entry_t)));
1753
1754     memset(&storerepl_list[i + 1], 0, sizeof(storerepl_entry_t));
1755
1756     storerepl_list[i].typestr = type;
1757
1758     storerepl_list[i].create = create;
1759 }
1760
1761 /*
1762  * Create a removal policy instance
1763  */
1764 RemovalPolicy *
1765 createRemovalPolicy(RemovalPolicySettings * settings)
1766 {
1767     storerepl_entry_t *r;
1768
1769     for (r = storerepl_list; r && r->typestr; ++r) {
1770         if (strcmp(r->typestr, settings->type) == 0)
1771             return r->create(settings->args);
1772     }
1773
1774     debugs(20, DBG_IMPORTANT, "ERROR: Unknown policy " << settings->type);
1775     debugs(20, DBG_IMPORTANT, "ERROR: Be sure to have set cache_replacement_policy");
1776     debugs(20, DBG_IMPORTANT, "ERROR:   and memory_replacement_policy in squid.conf!");
1777     fatalf("ERROR: Unknown policy %s\n", settings->type);
1778     return NULL;                /* NOTREACHED */
1779 }
1780
1781 #if 0
1782 void
1783 storeSwapFileNumberSet(StoreEntry * e, sfileno filn)
1784 {
1785     if (e->swap_file_number == filn)
1786         return;
1787
1788     if (filn < 0) {
1789         assert(-1 == filn);
1790         storeDirMapBitReset(e->swap_file_number);
1791         storeDirLRUDelete(e);
1792         e->swap_file_number = -1;
1793     } else {
1794         assert(-1 == e->swap_file_number);
1795         storeDirMapBitSet(e->swap_file_number = filn);
1796         storeDirLRUAdd(e);
1797     }
1798 }
1799
1800 #endif
1801
1802 /*
1803  * Replace a store entry with
1804  * a new reply. This eats the reply.
1805  */
1806 void
1807 StoreEntry::replaceHttpReply(HttpReply *rep, bool andStartWriting)
1808 {
1809     debugs(20, 3, "StoreEntry::replaceHttpReply: " << url());
1810
1811     if (!mem_obj) {
1812         debugs(20, DBG_CRITICAL, "Attempt to replace object with no in-memory representation");
1813         return;
1814     }
1815
1816     mem_obj->replaceHttpReply(rep);
1817
1818     if (andStartWriting)
1819         startWriting();
1820 }
1821
1822 void
1823 StoreEntry::startWriting()
1824 {
1825     Packer p;
1826
1827     /* TODO: when we store headers serparately remove the header portion */
1828     /* TODO: mark the length of the headers ? */
1829     /* We ONLY want the headers */
1830     packerToStoreInit(&p, this);
1831
1832     assert (isEmpty());
1833     assert(mem_obj);
1834
1835     const HttpReply *rep = getReply();
1836     assert(rep);
1837
1838     rep->packHeadersInto(&p);
1839     mem_obj->markEndOfReplyHeaders();
1840     EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
1841
1842     rep->body.packInto(&p);
1843
1844     packerClean(&p);
1845 }
1846
1847 char const *
1848 StoreEntry::getSerialisedMetaData()
1849 {
1850     StoreMeta *tlv_list = storeSwapMetaBuild(this);
1851     int swap_hdr_sz;
1852     char *result = storeSwapMetaPack(tlv_list, &swap_hdr_sz);
1853     storeSwapTLVFree(tlv_list);
1854     assert (swap_hdr_sz >= 0);
1855     mem_obj->swap_hdr_sz = (size_t) swap_hdr_sz;
1856     return result;
1857 }
1858
1859 void
1860 StoreEntry::trimMemory(const bool preserveSwappable)
1861 {
1862     /*
1863      * DPW 2007-05-09
1864      * Bug #1943.  We must not let go any data for IN_MEMORY
1865      * objects.  We have to wait until the mem_status changes.
1866      */
1867     if (mem_status == IN_MEMORY)
1868         return;
1869
1870     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1871         return; // cannot trim because we do not load them again
1872
1873     if (preserveSwappable)
1874         mem_obj->trimSwappable();
1875     else
1876         mem_obj->trimUnSwappable();
1877
1878     debugs(88, 7, *this << " inmem_lo=" << mem_obj->inmem_lo);
1879 }
1880
1881 bool
1882 StoreEntry::modifiedSince(HttpRequest * request) const
1883 {
1884     int object_length;
1885     time_t mod_time = lastmod;
1886
1887     if (mod_time < 0)
1888         mod_time = timestamp;
1889
1890     debugs(88, 3, "modifiedSince: '" << url() << "'");
1891
1892     debugs(88, 3, "modifiedSince: mod_time = " << mod_time);
1893
1894     if (mod_time < 0)
1895         return true;
1896
1897     /* Find size of the object */
1898     object_length = getReply()->content_length;
1899
1900     if (object_length < 0)
1901         object_length = contentLen();
1902
1903     if (mod_time > request->ims) {
1904         debugs(88, 3, "--> YES: entry newer than client");
1905         return true;
1906     } else if (mod_time < request->ims) {
1907         debugs(88, 3, "-->  NO: entry older than client");
1908         return false;
1909     } else if (request->imslen < 0) {
1910         debugs(88, 3, "-->  NO: same LMT, no client length");
1911         return false;
1912     } else if (request->imslen == object_length) {
1913         debugs(88, 3, "-->  NO: same LMT, same length");
1914         return false;
1915     } else {
1916         debugs(88, 3, "--> YES: same LMT, different length");
1917         return true;
1918     }
1919 }
1920
1921 bool
1922 StoreEntry::hasEtag(ETag &etag) const
1923 {
1924     if (const HttpReply *reply = getReply()) {
1925         etag = reply->header.getETag(HDR_ETAG);
1926         if (etag.str)
1927             return true;
1928     }
1929     return false;
1930 }
1931
1932 bool
1933 StoreEntry::hasIfMatchEtag(const HttpRequest &request) const
1934 {
1935     const String reqETags = request.header.getList(HDR_IF_MATCH);
1936     return hasOneOfEtags(reqETags, false);
1937 }
1938
1939 bool
1940 StoreEntry::hasIfNoneMatchEtag(const HttpRequest &request) const
1941 {
1942     const String reqETags = request.header.getList(HDR_IF_NONE_MATCH);
1943     // weak comparison is allowed only for HEAD or full-body GET requests
1944     const bool allowWeakMatch = !request.flags.isRanged &&
1945                                 (request.method == Http::METHOD_GET || request.method == Http::METHOD_HEAD);
1946     return hasOneOfEtags(reqETags, allowWeakMatch);
1947 }
1948
1949 /// whether at least one of the request ETags matches entity ETag
1950 bool
1951 StoreEntry::hasOneOfEtags(const String &reqETags, const bool allowWeakMatch) const
1952 {
1953     const ETag repETag = getReply()->header.getETag(HDR_ETAG);
1954     if (!repETag.str)
1955         return strListIsMember(&reqETags, "*", ',');
1956
1957     bool matched = false;
1958     const char *pos = NULL;
1959     const char *item;
1960     int ilen;
1961     while (!matched && strListGetItem(&reqETags, ',', &item, &ilen, &pos)) {
1962         if (!strncmp(item, "*", ilen))
1963             matched = true;
1964         else {
1965             String str;
1966             str.append(item, ilen);
1967             ETag reqETag;
1968             if (etagParseInit(&reqETag, str.termedBuf())) {
1969                 matched = allowWeakMatch ? etagIsWeakEqual(repETag, reqETag) :
1970                           etagIsStrongEqual(repETag, reqETag);
1971             }
1972         }
1973     }
1974     return matched;
1975 }
1976
1977 SwapDir::Pointer
1978 StoreEntry::store() const
1979 {
1980     assert(0 <= swap_dirn && swap_dirn < Config.cacheSwap.n_configured);
1981     return INDEXSD(swap_dirn);
1982 }
1983
1984 void
1985 StoreEntry::unlink()
1986 {
1987     store()->unlink(*this); // implies disconnect()
1988     swap_filen = -1;
1989     swap_dirn = -1;
1990     swap_status = SWAPOUT_NONE;
1991 }
1992
1993 /*
1994  * return true if the entry is in a state where
1995  * it can accept more data (ie with write() method)
1996  */
1997 bool
1998 StoreEntry::isAccepting() const
1999 {
2000     if (STORE_PENDING != store_status)
2001         return false;
2002
2003     if (EBIT_TEST(flags, ENTRY_ABORTED))
2004         return false;
2005
2006     return true;
2007 }
2008
2009 std::ostream &operator <<(std::ostream &os, const StoreEntry &e)
2010 {
2011     os << "e:";
2012
2013     if (e.mem_obj) {
2014         if (e.mem_obj->xitTable.index > -1)
2015             os << 't' << e.mem_obj->xitTable.index;
2016         if (e.mem_obj->memCache.index > -1)
2017             os << 'm' << e.mem_obj->memCache.index;
2018     }
2019     if (e.swap_filen > -1 || e.swap_dirn > -1)
2020         os << 'd' << e.swap_filen << '@' << e.swap_dirn;
2021
2022     os << '=';
2023
2024     // print only non-default status values, using unique letters
2025     if (e.mem_status != NOT_IN_MEMORY ||
2026         e.store_status != STORE_PENDING ||
2027         e.swap_status != SWAPOUT_NONE ||
2028         e.ping_status != PING_NONE) {
2029         if (e.mem_status != NOT_IN_MEMORY) os << 'm';
2030         if (e.store_status != STORE_PENDING) os << 's';
2031         if (e.swap_status != SWAPOUT_NONE) os << 'w' << e.swap_status;
2032         if (e.ping_status != PING_NONE) os << 'p' << e.ping_status;
2033     }
2034
2035     // print only set flags, using unique letters
2036     if (e.flags) {
2037         if (EBIT_TEST(e.flags, ENTRY_SPECIAL)) os << 'S';
2038         if (EBIT_TEST(e.flags, ENTRY_REVALIDATE)) os << 'R';
2039         if (EBIT_TEST(e.flags, DELAY_SENDING)) os << 'P';
2040         if (EBIT_TEST(e.flags, RELEASE_REQUEST)) os << 'X';
2041         if (EBIT_TEST(e.flags, REFRESH_REQUEST)) os << 'F';
2042         if (EBIT_TEST(e.flags, ENTRY_DISPATCHED)) os << 'D';
2043         if (EBIT_TEST(e.flags, KEY_PRIVATE)) os << 'I';
2044         if (EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT)) os << 'W';
2045         if (EBIT_TEST(e.flags, ENTRY_NEGCACHED)) os << 'N';
2046         if (EBIT_TEST(e.flags, ENTRY_VALIDATED)) os << 'V';
2047         if (EBIT_TEST(e.flags, ENTRY_BAD_LENGTH)) os << 'L';
2048         if (EBIT_TEST(e.flags, ENTRY_ABORTED)) os << 'A';
2049     }
2050
2051     if (e.mem_obj && e.mem_obj->smpCollapsed)
2052         os << 'O';
2053
2054     return os << '/' << &e << '*' << e.locks();
2055 }
2056
2057 /* NullStoreEntry */
2058
2059 NullStoreEntry NullStoreEntry::_instance;
2060
2061 NullStoreEntry *
2062 NullStoreEntry::getInstance()
2063 {
2064     return &_instance;
2065 }
2066
2067 char const *
2068 NullStoreEntry::getMD5Text() const
2069 {
2070     return "N/A";
2071 }
2072
2073 void
2074 NullStoreEntry::operator delete(void*)
2075 {
2076     fatal ("Attempt to delete NullStoreEntry\n");
2077 }
2078
2079 char const *
2080 NullStoreEntry::getSerialisedMetaData()
2081 {
2082     return NULL;
2083 }
2084
2085 #if !_USE_INLINE_
2086 #include "Store.cci"
2087 #endif