src/store.cc

   1 /*
   2  * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 20    Storage Manager */
  10
  11 #include "squid.h"
  12 #include "CacheDigest.h"
  13 #include "CacheManager.h"
  14 #include "comm/Connection.h"
  15 #include "comm/Read.h"
  16 #include "ETag.h"
  17 #include "event.h"
  18 #include "fde.h"
  19 #include "globals.h"
  20 #include "http.h"
  21 #include "HttpReply.h"
  22 #include "HttpRequest.h"
  23 #include "mem_node.h"
  24 #include "MemObject.h"
  25 #include "mgr/Registration.h"
  26 #include "mgr/StoreIoAction.h"
  27 #include "profiler/Profiler.h"
  28 #include "repl_modules.h"
  29 #include "RequestFlags.h"
  30 #include "SquidConfig.h"
  31 #include "SquidTime.h"
  32 #include "StatCounters.h"
  33 #include "stmem.h"
  34 #include "Store.h"
  35 #include "store/Controller.h"
  36 #include "store/Disk.h"
  37 #include "store/Disks.h"
  38 #include "store_digest.h"
  39 #include "store_key_md5.h"
  40 #include "store_log.h"
  41 #include "store_rebuild.h"
  42 #include "StoreClient.h"
  43 #include "StoreIOState.h"
  44 #include "StoreMeta.h"
  45 #include "StrList.h"
  46 #include "swap_log_op.h"
  47 #include "tools.h"
  48 #if USE_DELAY_POOLS
  49 #include "DelayPools.h"
  50 #endif
  51
  52 /** StoreEntry uses explicit new/delete operators, which set pool chunk size to 2MB
  53  * XXX: convert to MEMPROXY_CLASS() API
  54  */
  55 #include "mem/Pool.h"
  56
  57 #include <climits>
  58 #include <stack>
  59
  60 #define REBUILD_TIMESTAMP_DELTA_MAX 2
  61
  62 #define STORE_IN_MEM_BUCKETS            (229)
  63
  64 /** \todo Convert these string constants to enum string-arrays generated */
  65
  66 const char *memStatusStr[] = {
  67     "NOT_IN_MEMORY",
  68     "IN_MEMORY"
  69 };
  70
  71 const char *pingStatusStr[] = {
  72     "PING_NONE",
  73     "PING_WAITING",
  74     "PING_DONE"
  75 };
  76
  77 const char *storeStatusStr[] = {
  78     "STORE_OK",
  79     "STORE_PENDING"
  80 };
  81
  82 const char *swapStatusStr[] = {
  83     "SWAPOUT_NONE",
  84     "SWAPOUT_WRITING",
  85     "SWAPOUT_DONE"
  86 };
  87
  88 /*
  89  * This defines an repl type
  90  */
  91
  92 typedef struct _storerepl_entry storerepl_entry_t;
  93
  94 struct _storerepl_entry {
  95     const char *typestr;
  96     REMOVALPOLICYCREATE *create;
  97 };
  98
  99 static storerepl_entry_t *storerepl_list = NULL;
 100
 101 /*
 102  * local function prototypes
 103  */
 104 static int getKeyCounter(void);
 105 static OBJH storeCheckCachableStats;
 106 static EVH storeLateRelease;
 107
 108 /*
 109  * local variables
 110  */
 111 static std::stack<StoreEntry*> LateReleaseStack;
 112 MemAllocator *StoreEntry::pool = NULL;
 113
 114 void
 115 Store::Stats(StoreEntry * output)
 116 {
 117     assert(output);
 118     Root().stat(*output);
 119 }
 120
 121 // XXX: new/delete operators need to be replaced with MEMPROXY_CLASS
 122 // definitions but doing so exposes bug 4370, and maybe 4354 and 4355
 123 void *
 124 StoreEntry::operator new (size_t bytecount)
 125 {
 126     assert(bytecount == sizeof (StoreEntry));
 127
 128     if (!pool) {
 129         pool = memPoolCreate ("StoreEntry", bytecount);
 130     }
 131
 132     return pool->alloc();
 133 }
 134
 135 void
 136 StoreEntry::operator delete (void *address)
 137 {
 138     pool->freeOne(address);
 139 }
 140
 141 void
 142 StoreEntry::makePublic(const KeyScope scope)
 143 {
 144     /* This object can be cached for a long time */
 145     if (!EBIT_TEST(flags, RELEASE_REQUEST))
 146         setPublicKey(scope);
 147 }
 148
 149 void
 150 StoreEntry::makePrivate(const bool shareable)
 151 {
 152     /* This object should never be cached at all */
 153     expireNow();
 154     releaseRequest(shareable); /* delete object when not used */
 155 }
 156
 157 void
 158 StoreEntry::clearPrivate()
 159 {
 160     EBIT_CLR(flags, KEY_PRIVATE);
 161     shareableWhenPrivate = false;
 162 }
 163
 164 void
 165 StoreEntry::cacheNegatively()
 166 {
 167     /* This object may be negatively cached */
 168     negativeCache();
 169     makePublic();
 170 }
 171
 172 size_t
 173 StoreEntry::inUseCount()
 174 {
 175     if (!pool)
 176         return 0;
 177     return pool->getInUseCount();
 178 }
 179
 180 const char *
 181 StoreEntry::getMD5Text() const
 182 {
 183     return storeKeyText((const cache_key *)key);
 184 }
 185
 186 #include "comm.h"
 187
 188 void
 189 StoreEntry::DeferReader(void *theContext, CommRead const &aRead)
 190 {
 191     StoreEntry *anEntry = (StoreEntry *)theContext;
 192     anEntry->delayAwareRead(aRead.conn,
 193                             aRead.buf,
 194                             aRead.len,
 195                             aRead.callback);
 196 }
 197
 198 void
 199 StoreEntry::delayAwareRead(const Comm::ConnectionPointer &conn, char *buf, int len, AsyncCall::Pointer callback)
 200 {
 201     size_t amountToRead = bytesWanted(Range<size_t>(0, len));
 202     /* sketch: readdeferer* = getdeferer.
 203      * ->deferRead (fd, buf, len, callback, DelayAwareRead, this)
 204      */
 205
 206     if (amountToRead <= 0) {
 207         assert (mem_obj);
 208         mem_obj->delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 209         return;
 210     }
 211
 212     if (fd_table[conn->fd].closing()) {
 213         // Readers must have closing callbacks if they want to be notified. No
 214         // readers appeared to care around 2009/12/14 as they skipped reading
 215         // for other reasons. Closing may already be true at the delyaAwareRead
 216         // call time or may happen while we wait after delayRead() above.
 217         debugs(20, 3, HERE << "wont read from closing " << conn << " for " <<
 218                callback);
 219         return; // the read callback will never be called
 220     }
 221
 222     comm_read(conn, buf, amountToRead, callback);
 223 }
 224
 225 size_t
 226 StoreEntry::bytesWanted (Range<size_t> const aRange, bool ignoreDelayPools) const
 227 {
 228     if (mem_obj == NULL)
 229         return aRange.end;
 230
 231 #if URL_CHECKSUM_DEBUG
 232
 233     mem_obj->checkUrlChecksum();
 234
 235 #endif
 236
 237     if (!mem_obj->readAheadPolicyCanRead())
 238         return 0;
 239
 240     return mem_obj->mostBytesWanted(aRange.end, ignoreDelayPools);
 241 }
 242
 243 bool
 244 StoreEntry::checkDeferRead(int) const
 245 {
 246     return (bytesWanted(Range<size_t>(0,INT_MAX)) == 0);
 247 }
 248
 249 void
 250 StoreEntry::setNoDelay(bool const newValue)
 251 {
 252     if (mem_obj)
 253         mem_obj->setNoDelay(newValue);
 254 }
 255
 256 // XXX: Type names mislead. STORE_DISK_CLIENT actually means that we should
 257 //      open swapin file, aggressively trim memory, and ignore read-ahead gap.
 258 //      It does not mean we will read from disk exclusively (or at all!).
 259 // XXX: May create STORE_DISK_CLIENT with no disk caching configured.
 260 // XXX: Collapsed clients cannot predict their type.
 261 store_client_t
 262 StoreEntry::storeClientType() const
 263 {
 264     /* The needed offset isn't in memory
 265      * XXX TODO: this is wrong for range requests
 266      * as the needed offset may *not* be 0, AND
 267      * offset 0 in the memory object is the HTTP headers.
 268      */
 269
 270     assert(mem_obj);
 271
 272     if (mem_obj->inmem_lo)
 273         return STORE_DISK_CLIENT;
 274
 275     if (EBIT_TEST(flags, ENTRY_ABORTED)) {
 276         /* I don't think we should be adding clients to aborted entries */
 277         debugs(20, DBG_IMPORTANT, "storeClientType: adding to ENTRY_ABORTED entry");
 278         return STORE_MEM_CLIENT;
 279     }
 280
 281     if (store_status == STORE_OK) {
 282         /* the object has completed. */
 283
 284         if (mem_obj->inmem_lo == 0 && !isEmpty()) {
 285             if (swap_status == SWAPOUT_DONE) {
 286                 debugs(20,7, HERE << mem_obj << " lo: " << mem_obj->inmem_lo << " hi: " << mem_obj->endOffset() << " size: " << mem_obj->object_sz);
 287                 if (mem_obj->endOffset() == mem_obj->object_sz) {
 288                     /* hot object fully swapped in (XXX: or swapped out?) */
 289                     return STORE_MEM_CLIENT;
 290                 }
 291             } else {
 292                 /* Memory-only, or currently being swapped out */
 293                 return STORE_MEM_CLIENT;
 294             }
 295         }
 296         return STORE_DISK_CLIENT;
 297     }
 298
 299     /* here and past, entry is STORE_PENDING */
 300     /*
 301      * If this is the first client, let it be the mem client
 302      */
 303     if (mem_obj->nclients == 1)
 304         return STORE_MEM_CLIENT;
 305
 306     /*
 307      * If there is no disk file to open yet, we must make this a
 308      * mem client.  If we can't open the swapin file before writing
 309      * to the client, there is no guarantee that we will be able
 310      * to open it later when we really need it.
 311      */
 312     if (swap_status == SWAPOUT_NONE)
 313         return STORE_MEM_CLIENT;
 314
 315     /*
 316      * otherwise, make subsequent clients read from disk so they
 317      * can not delay the first, and vice-versa.
 318      */
 319     return STORE_DISK_CLIENT;
 320 }
 321
 322 StoreEntry::StoreEntry() :
 323     mem_obj(NULL),
 324     timestamp(-1),
 325     lastref(-1),
 326     expires(-1),
 327     lastModified_(-1),
 328     swap_file_sz(0),
 329     refcount(0),
 330     flags(0),
 331     swap_filen(-1),
 332     swap_dirn(-1),
 333     mem_status(NOT_IN_MEMORY),
 334     ping_status(PING_NONE),
 335     store_status(STORE_PENDING),
 336     swap_status(SWAPOUT_NONE),
 337     lock_count(0),
 338     shareableWhenPrivate(false)
 339 {
 340     debugs(20, 5, "StoreEntry constructed, this=" << this);
 341 }
 342
 343 StoreEntry::~StoreEntry()
 344 {
 345     debugs(20, 5, "StoreEntry destructed, this=" << this);
 346 }
 347
 348 #if USE_ADAPTATION
 349 void
 350 StoreEntry::deferProducer(const AsyncCall::Pointer &producer)
 351 {
 352     if (!deferredProducer)
 353         deferredProducer = producer;
 354     else
 355         debugs(20, 5, HERE << "Deferred producer call is allready set to: " <<
 356                *deferredProducer << ", requested call: " << *producer);
 357 }
 358
 359 void
 360 StoreEntry::kickProducer()
 361 {
 362     if (deferredProducer != NULL) {
 363         ScheduleCallHere(deferredProducer);
 364         deferredProducer = NULL;
 365     }
 366 }
 367 #endif
 368
 369 void
 370 StoreEntry::destroyMemObject()
 371 {
 372     debugs(20, 3, HERE << "destroyMemObject " << mem_obj);
 373
 374     if (MemObject *mem = mem_obj) {
 375         // Store::Root() is FATALly missing during shutdown
 376         if (mem->xitTable.index >= 0 && !shutting_down)
 377             Store::Root().transientsDisconnect(*mem);
 378         if (mem->memCache.index >= 0 && !shutting_down)
 379             Store::Root().memoryDisconnect(*this);
 380
 381         setMemStatus(NOT_IN_MEMORY);
 382         mem_obj = NULL;
 383         delete mem;
 384     }
 385 }
 386
 387 void
 388 destroyStoreEntry(void *data)
 389 {
 390     debugs(20, 3, HERE << "destroyStoreEntry: destroying " <<  data);
 391     StoreEntry *e = static_cast<StoreEntry *>(static_cast<hash_link *>(data));
 392     assert(e != NULL);
 393
 394     if (e == NullStoreEntry::getInstance())
 395         return;
 396
 397     // Store::Root() is FATALly missing during shutdown
 398     if (e->swap_filen >= 0 && !shutting_down)
 399         e->disk().disconnect(*e);
 400
 401     e->destroyMemObject();
 402
 403     e->hashDelete();
 404
 405     assert(e->key == NULL);
 406
 407     delete e;
 408 }
 409
 410 /* ----- INTERFACE BETWEEN STORAGE MANAGER AND HASH TABLE FUNCTIONS --------- */
 411
 412 void
 413 StoreEntry::hashInsert(const cache_key * someKey)
 414 {
 415     debugs(20, 3, "StoreEntry::hashInsert: Inserting Entry " << *this << " key '" << storeKeyText(someKey) << "'");
 416     key = storeKeyDup(someKey);
 417     hash_join(store_table, this);
 418 }
 419
 420 void
 421 StoreEntry::hashDelete()
 422 {
 423     if (key) { // some test cases do not create keys and do not hashInsert()
 424         hash_remove_link(store_table, this);
 425         storeKeyFree((const cache_key *)key);
 426         key = NULL;
 427     }
 428 }
 429
 430 /* -------------------------------------------------------------------------- */
 431
 432 /* get rid of memory copy of the object */
 433 void
 434 StoreEntry::purgeMem()
 435 {
 436     if (mem_obj == NULL)
 437         return;
 438
 439     debugs(20, 3, "StoreEntry::purgeMem: Freeing memory-copy of " << getMD5Text());
 440
 441     Store::Root().memoryUnlink(*this);
 442
 443     if (swap_status != SWAPOUT_DONE)
 444         release();
 445 }
 446
 447 void
 448 StoreEntry::lock(const char *context)
 449 {
 450     ++lock_count;
 451     debugs(20, 3, context << " locked key " << getMD5Text() << ' ' << *this);
 452 }
 453
 454 void
 455 StoreEntry::touch()
 456 {
 457     lastref = squid_curtime;
 458 }
 459
 460 void
 461 StoreEntry::setReleaseFlag()
 462 {
 463     if (EBIT_TEST(flags, RELEASE_REQUEST))
 464         return;
 465
 466     debugs(20, 3, "StoreEntry::setReleaseFlag: '" << getMD5Text() << "'");
 467
 468     EBIT_SET(flags, RELEASE_REQUEST);
 469
 470     Store::Root().markForUnlink(*this);
 471 }
 472
 473 void
 474 StoreEntry::releaseRequest(const bool shareable)
 475 {
 476     if (EBIT_TEST(flags, RELEASE_REQUEST))
 477         return;
 478
 479     setReleaseFlag(); // makes validToSend() false, preventing future hits
 480
 481     setPrivateKey(shareable);
 482 }
 483
 484 int
 485 StoreEntry::unlock(const char *context)
 486 {
 487     debugs(20, 3, (context ? context : "somebody") <<
 488            " unlocking key " << getMD5Text() << ' ' << *this);
 489     assert(lock_count > 0);
 490     --lock_count;
 491
 492     if (lock_count)
 493         return (int) lock_count;
 494
 495     if (store_status == STORE_PENDING)
 496         setReleaseFlag();
 497
 498     assert(storePendingNClients(this) == 0);
 499
 500     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 501         this->release();
 502         return 0;
 503     }
 504
 505     if (EBIT_TEST(flags, KEY_PRIVATE))
 506         debugs(20, DBG_IMPORTANT, "WARNING: " << __FILE__ << ":" << __LINE__ << ": found KEY_PRIVATE");
 507
 508     Store::Root().handleIdleEntry(*this); // may delete us
 509     return 0;
 510 }
 511
 512 void
 513 StoreEntry::getPublicByRequestMethod  (StoreClient *aClient, HttpRequest * request, const HttpRequestMethod& method)
 514 {
 515     assert (aClient);
 516     StoreEntry *result = storeGetPublicByRequestMethod( request, method);
 517
 518     if (!result)
 519         aClient->created (NullStoreEntry::getInstance());
 520     else
 521         aClient->created (result);
 522 }
 523
 524 void
 525 StoreEntry::getPublicByRequest (StoreClient *aClient, HttpRequest * request)
 526 {
 527     assert (aClient);
 528     StoreEntry *result = storeGetPublicByRequest (request);
 529
 530     if (!result)
 531         result = NullStoreEntry::getInstance();
 532
 533     aClient->created (result);
 534 }
 535
 536 void
 537 StoreEntry::getPublic (StoreClient *aClient, const char *uri, const HttpRequestMethod& method)
 538 {
 539     assert (aClient);
 540     StoreEntry *result = storeGetPublic (uri, method);
 541
 542     if (!result)
 543         result = NullStoreEntry::getInstance();
 544
 545     aClient->created (result);
 546 }
 547
 548 StoreEntry *
 549 storeGetPublic(const char *uri, const HttpRequestMethod& method)
 550 {
 551     return Store::Root().get(storeKeyPublic(uri, method));
 552 }
 553
 554 StoreEntry *
 555 storeGetPublicByRequestMethod(HttpRequest * req, const HttpRequestMethod& method, const KeyScope keyScope)
 556 {
 557     return Store::Root().get(storeKeyPublicByRequestMethod(req, method, keyScope));
 558 }
 559
 560 StoreEntry *
 561 storeGetPublicByRequest(HttpRequest * req, const KeyScope keyScope)
 562 {
 563     StoreEntry *e = storeGetPublicByRequestMethod(req, req->method, keyScope);
 564
 565     if (e == NULL && req->method == Http::METHOD_HEAD)
 566         /* We can generate a HEAD reply from a cached GET object */
 567         e = storeGetPublicByRequestMethod(req, Http::METHOD_GET, keyScope);
 568
 569     return e;
 570 }
 571
 572 static int
 573 getKeyCounter(void)
 574 {
 575     static int key_counter = 0;
 576
 577     if (++key_counter < 0)
 578         key_counter = 1;
 579
 580     return key_counter;
 581 }
 582
 583 /* RBC 20050104 AFAICT this should become simpler:
 584  * rather than reinserting with a special key it should be marked
 585  * as 'released' and then cleaned up when refcounting indicates.
 586  * the StoreHashIndex could well implement its 'released' in the
 587  * current manner.
 588  * Also, clean log writing should skip over ia,t
 589  * Otherwise, we need a 'remove from the index but not the store
 590  * concept'.
 591  */
 592 void
 593 StoreEntry::setPrivateKey(const bool shareable)
 594 {
 595     if (key && EBIT_TEST(flags, KEY_PRIVATE)) {
 596         // The entry is already private, but it may be still shareable.
 597         if (!shareable)
 598             shareableWhenPrivate = false;
 599         return;
 600     }
 601
 602     if (key) {
 603         setReleaseFlag(); // will markForUnlink(); all caches/workers will know
 604
 605         // TODO: move into SwapDir::markForUnlink() already called by Root()
 606         if (swap_filen > -1)
 607             storeDirSwapLog(this, SWAP_LOG_DEL);
 608
 609         hashDelete();
 610     }
 611
 612     if (mem_obj && mem_obj->hasUris())
 613         mem_obj->id = getKeyCounter();
 614     const cache_key *newkey = storeKeyPrivate();
 615
 616     assert(hash_lookup(store_table, newkey) == NULL);
 617     EBIT_SET(flags, KEY_PRIVATE);
 618     shareableWhenPrivate = shareable;
 619     hashInsert(newkey);
 620 }
 621
 622 void
 623 StoreEntry::setPublicKey(const KeyScope scope)
 624 {
 625     if (key && !EBIT_TEST(flags, KEY_PRIVATE))
 626         return;                 /* is already public */
 627
 628     assert(mem_obj);
 629
 630     /*
 631      * We can't make RELEASE_REQUEST objects public.  Depending on
 632      * when RELEASE_REQUEST gets set, we might not be swapping out
 633      * the object.  If we're not swapping out, then subsequent
 634      * store clients won't be able to access object data which has
 635      * been freed from memory.
 636      *
 637      * If RELEASE_REQUEST is set, setPublicKey() should not be called.
 638      */
 639 #if MORE_DEBUG_OUTPUT
 640
 641     if (EBIT_TEST(flags, RELEASE_REQUEST))
 642         debugs(20, DBG_IMPORTANT, "assertion failed: RELEASE key " << key << ", url " << mem_obj->url);
 643
 644 #endif
 645
 646     assert(!EBIT_TEST(flags, RELEASE_REQUEST));
 647
 648     adjustVary();
 649     forcePublicKey(calcPublicKey(scope));
 650 }
 651
 652 void
 653 StoreEntry::clearPublicKeyScope()
 654 {
 655     if (!key || EBIT_TEST(flags, KEY_PRIVATE))
 656         return; // probably the old public key was deleted or made private
 657
 658     // TODO: adjustVary() when collapsed revalidation supports that
 659
 660     const cache_key *newKey = calcPublicKey(ksDefault);
 661     if (!storeKeyHashCmp(key, newKey))
 662         return; // probably another collapsed revalidation beat us to this change
 663
 664     forcePublicKey(newKey);
 665 }
 666
 667 /// Unconditionally sets public key for this store entry.
 668 /// Releases the old entry with the same public key (if any).
 669 void
 670 StoreEntry::forcePublicKey(const cache_key *newkey)
 671 {
 672     if (StoreEntry *e2 = (StoreEntry *)hash_lookup(store_table, newkey)) {
 673         assert(e2 != this);
 674         debugs(20, 3, "Making old " << *e2 << " private.");
 675
 676         // TODO: check whether there is any sense in keeping old entry
 677         // shareable here. Leaving it non-shareable for now.
 678         e2->setPrivateKey(false);
 679         e2->release(false);
 680     }
 681
 682     if (key)
 683         hashDelete();
 684
 685     clearPrivate();
 686
 687     hashInsert(newkey);
 688
 689     if (swap_filen > -1)
 690         storeDirSwapLog(this, SWAP_LOG_ADD);
 691 }
 692
 693 /// Calculates correct public key for feeding forcePublicKey().
 694 /// Assumes adjustVary() has been called for this entry already.
 695 const cache_key *
 696 StoreEntry::calcPublicKey(const KeyScope keyScope)
 697 {
 698     assert(mem_obj);
 699     return mem_obj->request ? storeKeyPublicByRequest(mem_obj->request.getRaw(), keyScope) :
 700            storeKeyPublic(mem_obj->storeId(), mem_obj->method, keyScope);
 701 }
 702
 703 /// Updates mem_obj->request->vary_headers to reflect the current Vary.
 704 /// The vary_headers field is used to calculate the Vary marker key.
 705 /// Releases the old Vary marker with an outdated key (if any).
 706 void
 707 StoreEntry::adjustVary()
 708 {
 709     assert(mem_obj);
 710
 711     if (!mem_obj->request)
 712         return;
 713
 714     HttpRequestPointer request(mem_obj->request);
 715
 716     if (mem_obj->vary_headers.isEmpty()) {
 717         /* First handle the case where the object no longer varies */
 718         request->vary_headers.clear();
 719     } else {
 720         if (!request->vary_headers.isEmpty() && request->vary_headers.cmp(mem_obj->vary_headers) != 0) {
 721             /* Oops.. the variance has changed. Kill the base object
 722              * to record the new variance key
 723              */
 724             request->vary_headers.clear();       /* free old "bad" variance key */
 725             if (StoreEntry *pe = storeGetPublic(mem_obj->storeId(), mem_obj->method))
 726                 pe->release();
 727         }
 728
 729         /* Make sure the request knows the variance status */
 730         if (request->vary_headers.isEmpty())
 731             request->vary_headers = httpMakeVaryMark(request.getRaw(), mem_obj->getReply().getRaw());
 732     }
 733
 734     // TODO: storeGetPublic() calls below may create unlocked entries.
 735     // We should add/use storeHas() API or lock/unlock those entries.
 736     if (!mem_obj->vary_headers.isEmpty() && !storeGetPublic(mem_obj->storeId(), mem_obj->method)) {
 737         /* Create "vary" base object */
 738         String vary;
 739         StoreEntry *pe = storeCreateEntry(mem_obj->storeId(), mem_obj->logUri(), request->flags, request->method);
 740         /* We are allowed to do this typecast */
 741         HttpReply *rep = new HttpReply;
 742         rep->setHeaders(Http::scOkay, "Internal marker object", "x-squid-internal/vary", -1, -1, squid_curtime + 100000);
 743         vary = mem_obj->getReply()->header.getList(Http::HdrType::VARY);
 744
 745         if (vary.size()) {
 746             /* Again, we own this structure layout */
 747             rep->header.putStr(Http::HdrType::VARY, vary.termedBuf());
 748             vary.clean();
 749         }
 750
 751 #if X_ACCELERATOR_VARY
 752         vary = mem_obj->getReply()->header.getList(Http::HdrType::HDR_X_ACCELERATOR_VARY);
 753
 754         if (vary.size() > 0) {
 755             /* Again, we own this structure layout */
 756             rep->header.putStr(Http::HdrType::HDR_X_ACCELERATOR_VARY, vary.termedBuf());
 757             vary.clean();
 758         }
 759
 760 #endif
 761         pe->replaceHttpReply(rep, false); // no write until key is public
 762
 763         pe->timestampsSet();
 764
 765         pe->makePublic();
 766
 767         pe->startWriting(); // after makePublic()
 768
 769         pe->complete();
 770
 771         pe->unlock("StoreEntry::forcePublicKey+Vary");
 772     }
 773 }
 774
 775 StoreEntry *
 776 storeCreatePureEntry(const char *url, const char *log_url, const RequestFlags &flags, const HttpRequestMethod& method)
 777 {
 778     StoreEntry *e = NULL;
 779     debugs(20, 3, "storeCreateEntry: '" << url << "'");
 780
 781     e = new StoreEntry();
 782     e->makeMemObject();
 783     e->mem_obj->setUris(url, log_url, method);
 784
 785     if (flags.cachable) {
 786         EBIT_CLR(e->flags, RELEASE_REQUEST);
 787     } else {
 788         e->releaseRequest();
 789     }
 790
 791     e->store_status = STORE_PENDING;
 792     e->refcount = 0;
 793     e->lastref = squid_curtime;
 794     e->timestamp = -1;          /* set in StoreEntry::timestampsSet() */
 795     e->ping_status = PING_NONE;
 796     EBIT_SET(e->flags, ENTRY_VALIDATED);
 797     return e;
 798 }
 799
 800 StoreEntry *
 801 storeCreateEntry(const char *url, const char *logUrl, const RequestFlags &flags, const HttpRequestMethod& method)
 802 {
 803     StoreEntry *e = storeCreatePureEntry(url, logUrl, flags, method);
 804     e->lock("storeCreateEntry");
 805
 806     if (neighbors_do_private_keys || !flags.hierarchical)
 807         e->setPrivateKey(false);
 808     else
 809         e->setPublicKey();
 810
 811     return e;
 812 }
 813
 814 /* Mark object as expired */
 815 void
 816 StoreEntry::expireNow()
 817 {
 818     debugs(20, 3, "StoreEntry::expireNow: '" << getMD5Text() << "'");
 819     expires = squid_curtime;
 820 }
 821
 822 void
 823 StoreEntry::write (StoreIOBuffer writeBuffer)
 824 {
 825     assert(mem_obj != NULL);
 826     /* This assert will change when we teach the store to update */
 827     PROF_start(StoreEntry_write);
 828     assert(store_status == STORE_PENDING);
 829
 830     // XXX: caller uses content offset, but we also store headers
 831     if (const HttpReplyPointer reply = mem_obj->getReply())
 832         writeBuffer.offset += reply->hdr_sz;
 833
 834     debugs(20, 5, "storeWrite: writing " << writeBuffer.length << " bytes for '" << getMD5Text() << "'");
 835     PROF_stop(StoreEntry_write);
 836     storeGetMemSpace(writeBuffer.length);
 837     mem_obj->write(writeBuffer);
 838
 839     if (!EBIT_TEST(flags, DELAY_SENDING))
 840         invokeHandlers();
 841 }
 842
 843 /* Append incoming data from a primary server to an entry. */
 844 void
 845 StoreEntry::append(char const *buf, int len)
 846 {
 847     assert(mem_obj != NULL);
 848     assert(len >= 0);
 849     assert(store_status == STORE_PENDING);
 850
 851     StoreIOBuffer tempBuffer;
 852     tempBuffer.data = (char *)buf;
 853     tempBuffer.length = len;
 854     /*
 855      * XXX sigh, offset might be < 0 here, but it gets "corrected"
 856      * later.  This offset crap is such a mess.
 857      */
 858     tempBuffer.offset = mem_obj->endOffset() - (getReply() ? getReply()->hdr_sz : 0);
 859     write(tempBuffer);
 860 }
 861
 862 void
 863 StoreEntry::vappendf(const char *fmt, va_list vargs)
 864 {
 865     LOCAL_ARRAY(char, buf, 4096);
 866     *buf = 0;
 867     int x;
 868
 869 #ifdef VA_COPY
 870     va_args ap;
 871     /* Fix of bug 753r. The value of vargs is undefined
 872      * after vsnprintf() returns. Make a copy of vargs
 873      * incase we loop around and call vsnprintf() again.
 874      */
 875     VA_COPY(ap,vargs);
 876     errno = 0;
 877     if ((x = vsnprintf(buf, sizeof(buf), fmt, ap)) < 0) {
 878         fatal(xstrerr(errno));
 879         return;
 880     }
 881     va_end(ap);
 882 #else /* VA_COPY */
 883     errno = 0;
 884     if ((x = vsnprintf(buf, sizeof(buf), fmt, vargs)) < 0) {
 885         fatal(xstrerr(errno));
 886         return;
 887     }
 888 #endif /*VA_COPY*/
 889
 890     if (x < static_cast<int>(sizeof(buf))) {
 891         append(buf, x);
 892         return;
 893     }
 894
 895     // okay, do it the slow way.
 896     char *buf2 = new char[x+1];
 897     int y = vsnprintf(buf2, x+1, fmt, vargs);
 898     assert(y >= 0 && y == x);
 899     append(buf2, y);
 900     delete[] buf2;
 901 }
 902
 903 // deprecated. use StoreEntry::appendf() instead.
 904 void
 905 storeAppendPrintf(StoreEntry * e, const char *fmt,...)
 906 {
 907     va_list args;
 908     va_start(args, fmt);
 909     e->vappendf(fmt, args);
 910     va_end(args);
 911 }
 912
 913 // deprecated. use StoreEntry::appendf() instead.
 914 void
 915 storeAppendVPrintf(StoreEntry * e, const char *fmt, va_list vargs)
 916 {
 917     e->vappendf(fmt, vargs);
 918 }
 919
 920 struct _store_check_cachable_hist {
 921
 922     struct {
 923         int non_get;
 924         int not_entry_cachable;
 925         int wrong_content_length;
 926         int negative_cached;
 927         int too_big;
 928         int too_small;
 929         int private_key;
 930         int too_many_open_files;
 931         int too_many_open_fds;
 932         int missing_parts;
 933     } no;
 934
 935     struct {
 936         int Default;
 937     } yes;
 938 } store_check_cachable_hist;
 939
 940 int
 941 storeTooManyDiskFilesOpen(void)
 942 {
 943     if (Config.max_open_disk_fds == 0)
 944         return 0;
 945
 946     if (store_open_disk_fd > Config.max_open_disk_fds)
 947         return 1;
 948
 949     return 0;
 950 }
 951
 952 int
 953 StoreEntry::checkTooSmall()
 954 {
 955     if (EBIT_TEST(flags, ENTRY_SPECIAL))
 956         return 0;
 957
 958     if (STORE_OK == store_status)
 959         if (mem_obj->object_sz >= 0 &&
 960                 mem_obj->object_sz < Config.Store.minObjectSize)
 961             return 1;
 962     if (getReply()->content_length > -1)
 963         if (getReply()->content_length < Config.Store.minObjectSize)
 964             return 1;
 965     return 0;
 966 }
 967
 968 bool
 969 StoreEntry::checkTooBig() const
 970 {
 971     if (mem_obj->endOffset() > store_maxobjsize)
 972         return true;
 973
 974     if (getReply()->content_length < 0)
 975         return false;
 976
 977     return (getReply()->content_length > store_maxobjsize);
 978 }
 979
 980 // TODO: move "too many open..." checks outside -- we are called too early/late
 981 bool
 982 StoreEntry::checkCachable()
 983 {
 984     // XXX: This method is used for both memory and disk caches, but some
 985     // checks are specific to disk caches. Move them to mayStartSwapOut().
 986
 987     // XXX: This method may be called several times, sometimes with different
 988     // outcomes, making store_check_cachable_hist counters misleading.
 989
 990     // check this first to optimize handling of repeated calls for uncachables
 991     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 992         debugs(20, 2, "StoreEntry::checkCachable: NO: not cachable");
 993         ++store_check_cachable_hist.no.not_entry_cachable; // TODO: rename?
 994         return 0; // avoid rerequesting release below
 995     }
 996
 997 #if CACHE_ALL_METHODS
 998
 999     if (mem_obj->method != Http::METHOD_GET) {
1000         debugs(20, 2, "StoreEntry::checkCachable: NO: non-GET method");
1001         ++store_check_cachable_hist.no.non_get;
1002     } else
1003 #endif
1004         if (store_status == STORE_OK && EBIT_TEST(flags, ENTRY_BAD_LENGTH)) {
1005             debugs(20, 2, "StoreEntry::checkCachable: NO: wrong content-length");
1006             ++store_check_cachable_hist.no.wrong_content_length;
1007         } else if (EBIT_TEST(flags, ENTRY_NEGCACHED)) {
1008             debugs(20, 3, "StoreEntry::checkCachable: NO: negative cached");
1009             ++store_check_cachable_hist.no.negative_cached;
1010             return 0;           /* avoid release call below */
1011         } else if (!mem_obj || !getReply()) {
1012             // XXX: In bug 4131, we forgetHit() without mem_obj, so we need
1013             // this segfault protection, but how can we get such a HIT?
1014             debugs(20, 2, "StoreEntry::checkCachable: NO: missing parts: " << *this);
1015             ++store_check_cachable_hist.no.missing_parts;
1016         } else if (checkTooBig()) {
1017             debugs(20, 2, "StoreEntry::checkCachable: NO: too big");
1018             ++store_check_cachable_hist.no.too_big;
1019         } else if (checkTooSmall()) {
1020             debugs(20, 2, "StoreEntry::checkCachable: NO: too small");
1021             ++store_check_cachable_hist.no.too_small;
1022         } else if (EBIT_TEST(flags, KEY_PRIVATE)) {
1023             debugs(20, 3, "StoreEntry::checkCachable: NO: private key");
1024             ++store_check_cachable_hist.no.private_key;
1025         } else if (swap_status != SWAPOUT_NONE) {
1026             /*
1027              * here we checked the swap_status because the remaining
1028              * cases are only relevant only if we haven't started swapping
1029              * out the object yet.
1030              */
1031             return 1;
1032         } else if (storeTooManyDiskFilesOpen()) {
1033             debugs(20, 2, "StoreEntry::checkCachable: NO: too many disk files open");
1034             ++store_check_cachable_hist.no.too_many_open_files;
1035         } else if (fdNFree() < RESERVED_FD) {
1036             debugs(20, 2, "StoreEntry::checkCachable: NO: too many FD's open");
1037             ++store_check_cachable_hist.no.too_many_open_fds;
1038         } else {
1039             ++store_check_cachable_hist.yes.Default;
1040             return 1;
1041         }
1042
1043     releaseRequest();
1044     return 0;
1045 }
1046
1047 void
1048 storeCheckCachableStats(StoreEntry *sentry)
1049 {
1050     storeAppendPrintf(sentry, "Category\t Count\n");
1051
1052 #if CACHE_ALL_METHODS
1053
1054     storeAppendPrintf(sentry, "no.non_get\t%d\n",
1055                       store_check_cachable_hist.no.non_get);
1056 #endif
1057
1058     storeAppendPrintf(sentry, "no.not_entry_cachable\t%d\n",
1059                       store_check_cachable_hist.no.not_entry_cachable);
1060     storeAppendPrintf(sentry, "no.wrong_content_length\t%d\n",
1061                       store_check_cachable_hist.no.wrong_content_length);
1062     storeAppendPrintf(sentry, "no.negative_cached\t%d\n",
1063                       store_check_cachable_hist.no.negative_cached);
1064     storeAppendPrintf(sentry, "no.missing_parts\t%d\n",
1065                       store_check_cachable_hist.no.missing_parts);
1066     storeAppendPrintf(sentry, "no.too_big\t%d\n",
1067                       store_check_cachable_hist.no.too_big);
1068     storeAppendPrintf(sentry, "no.too_small\t%d\n",
1069                       store_check_cachable_hist.no.too_small);
1070     storeAppendPrintf(sentry, "no.private_key\t%d\n",
1071                       store_check_cachable_hist.no.private_key);
1072     storeAppendPrintf(sentry, "no.too_many_open_files\t%d\n",
1073                       store_check_cachable_hist.no.too_many_open_files);
1074     storeAppendPrintf(sentry, "no.too_many_open_fds\t%d\n",
1075                       store_check_cachable_hist.no.too_many_open_fds);
1076     storeAppendPrintf(sentry, "yes.default\t%d\n",
1077                       store_check_cachable_hist.yes.Default);
1078 }
1079
1080 void
1081 StoreEntry::lengthWentBad(const char *reason)
1082 {
1083     debugs(20, 3, "because " << reason << ": " << *this);
1084     EBIT_SET(flags, ENTRY_BAD_LENGTH);
1085     releaseRequest();
1086 }
1087
1088 void
1089 StoreEntry::complete()
1090 {
1091     debugs(20, 3, "storeComplete: '" << getMD5Text() << "'");
1092
1093     if (store_status != STORE_PENDING) {
1094         /*
1095          * if we're not STORE_PENDING, then probably we got aborted
1096          * and there should be NO clients on this entry
1097          */
1098         assert(EBIT_TEST(flags, ENTRY_ABORTED));
1099         assert(mem_obj->nclients == 0);
1100         return;
1101     }
1102
1103     /* This is suspect: mem obj offsets include the headers. do we adjust for that
1104      * in use of object_sz?
1105      */
1106     mem_obj->object_sz = mem_obj->endOffset();
1107
1108     store_status = STORE_OK;
1109
1110     assert(mem_status == NOT_IN_MEMORY);
1111
1112     if (!EBIT_TEST(flags, ENTRY_BAD_LENGTH) && !validLength())
1113         lengthWentBad("!validLength() in complete()");
1114
1115 #if USE_CACHE_DIGESTS
1116     if (mem_obj->request)
1117         mem_obj->request->hier.store_complete_stop = current_time;
1118
1119 #endif
1120     /*
1121      * We used to call invokeHandlers, then storeSwapOut.  However,
1122      * Madhukar Reddy <myreddy@persistence.com> reported that
1123      * responses without content length would sometimes get released
1124      * in client_side, thinking that the response is incomplete.
1125      */
1126     invokeHandlers();
1127 }
1128
1129 /*
1130  * Someone wants to abort this transfer.  Set the reason in the
1131  * request structure, call the callback and mark the
1132  * entry for releasing
1133  */
1134 void
1135 StoreEntry::abort()
1136 {
1137     ++statCounter.aborted_requests;
1138     assert(store_status == STORE_PENDING);
1139     assert(mem_obj != NULL);
1140     debugs(20, 6, "storeAbort: " << getMD5Text());
1141
1142     lock("StoreEntry::abort");         /* lock while aborting */
1143     negativeCache();
1144
1145     releaseRequest();
1146
1147     EBIT_SET(flags, ENTRY_ABORTED);
1148
1149     setMemStatus(NOT_IN_MEMORY);
1150
1151     store_status = STORE_OK;
1152
1153     /* Notify the server side */
1154
1155     /*
1156      * DPW 2007-05-07
1157      * Should we check abort.data for validity?
1158      */
1159     if (mem_obj->abort.callback) {
1160         if (!cbdataReferenceValid(mem_obj->abort.data))
1161             debugs(20, DBG_IMPORTANT,HERE << "queueing event when abort.data is not valid");
1162         eventAdd("mem_obj->abort.callback",
1163                  mem_obj->abort.callback,
1164                  mem_obj->abort.data,
1165                  0.0,
1166                  true);
1167         unregisterAbort();
1168     }
1169
1170     /* XXX Should we reverse these two, so that there is no
1171      * unneeded disk swapping triggered?
1172      */
1173     /* Notify the client side */
1174     invokeHandlers();
1175
1176     // abort swap out, invalidating what was created so far (release follows)
1177     swapOutFileClose(StoreIOState::writerGone);
1178
1179     unlock("StoreEntry::abort");       /* unlock */
1180 }
1181
1182 /**
1183  * Clear Memory storage to accommodate the given object len
1184  */
1185 void
1186 storeGetMemSpace(int size)
1187 {
1188     PROF_start(storeGetMemSpace);
1189     StoreEntry *e = NULL;
1190     int released = 0;
1191     static time_t last_check = 0;
1192     size_t pages_needed;
1193     RemovalPurgeWalker *walker;
1194
1195     if (squid_curtime == last_check) {
1196         PROF_stop(storeGetMemSpace);
1197         return;
1198     }
1199
1200     last_check = squid_curtime;
1201
1202     pages_needed = (size + SM_PAGE_SIZE-1) / SM_PAGE_SIZE;
1203
1204     if (mem_node::InUseCount() + pages_needed < store_pages_max) {
1205         PROF_stop(storeGetMemSpace);
1206         return;
1207     }
1208
1209     debugs(20, 2, "storeGetMemSpace: Starting, need " << pages_needed <<
1210            " pages");
1211
1212     /* XXX what to set as max_scan here? */
1213     walker = mem_policy->PurgeInit(mem_policy, 100000);
1214
1215     while ((e = walker->Next(walker))) {
1216         e->purgeMem();
1217         ++released;
1218
1219         if (mem_node::InUseCount() + pages_needed < store_pages_max)
1220             break;
1221     }
1222
1223     walker->Done(walker);
1224     debugs(20, 3, "storeGetMemSpace stats:");
1225     debugs(20, 3, "  " << std::setw(6) << hot_obj_count  << " HOT objects");
1226     debugs(20, 3, "  " << std::setw(6) << released  << " were released");
1227     PROF_stop(storeGetMemSpace);
1228 }
1229
1230 /* thunk through to Store::Root().maintain(). Note that this would be better still
1231  * if registered against the root store itself, but that requires more complex
1232  * update logic - bigger fish to fry first. Long term each store when
1233  * it becomes active will self register
1234  */
1235 void
1236 Store::Maintain(void *)
1237 {
1238     Store::Root().maintain();
1239
1240     /* Reregister a maintain event .. */
1241     eventAdd("MaintainSwapSpace", Maintain, NULL, 1.0, 1);
1242
1243 }
1244
1245 /* The maximum objects to scan for maintain storage space */
1246 #define MAINTAIN_MAX_SCAN       1024
1247 #define MAINTAIN_MAX_REMOVE     64
1248
1249 /* release an object from a cache */
1250 void
1251 StoreEntry::release(const bool shareable)
1252 {
1253     PROF_start(storeRelease);
1254     debugs(20, 3, "releasing " << *this << ' ' << getMD5Text());
1255     /* If, for any reason we can't discard this object because of an
1256      * outstanding request, mark it for pending release */
1257
1258     if (locked()) {
1259         expireNow();
1260         debugs(20, 3, "storeRelease: Only setting RELEASE_REQUEST bit");
1261         releaseRequest(shareable);
1262         PROF_stop(storeRelease);
1263         return;
1264     }
1265
1266     if (Store::Controller::store_dirs_rebuilding && swap_filen > -1) {
1267         /* TODO: Teach disk stores to handle releases during rebuild instead. */
1268
1269         Store::Root().memoryUnlink(*this);
1270
1271         setPrivateKey(shareable);
1272
1273         // lock the entry until rebuilding is done
1274         lock("storeLateRelease");
1275         setReleaseFlag();
1276         LateReleaseStack.push(this);
1277         return;
1278     }
1279
1280     storeLog(STORE_LOG_RELEASE, this);
1281     if (swap_filen > -1 && !EBIT_TEST(flags, KEY_PRIVATE)) {
1282         // log before unlink() below clears swap_filen
1283         storeDirSwapLog(this, SWAP_LOG_DEL);
1284     }
1285
1286     Store::Root().unlink(*this);
1287     destroyStoreEntry(static_cast<hash_link *>(this));
1288     PROF_stop(storeRelease);
1289 }
1290
1291 static void
1292 storeLateRelease(void *)
1293 {
1294     StoreEntry *e;
1295     static int n = 0;
1296
1297     if (Store::Controller::store_dirs_rebuilding) {
1298         eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1299         return;
1300     }
1301
1302     // TODO: this works but looks unelegant.
1303     for (int i = 0; i < 10; ++i) {
1304         if (LateReleaseStack.empty()) {
1305             debugs(20, DBG_IMPORTANT, "storeLateRelease: released " << n << " objects");
1306             return;
1307         } else {
1308             e = LateReleaseStack.top();
1309             LateReleaseStack.pop();
1310         }
1311
1312         e->unlock("storeLateRelease");
1313         ++n;
1314     }
1315
1316     eventAdd("storeLateRelease", storeLateRelease, NULL, 0.0, 1);
1317 }
1318
1319 /* return 1 if a store entry is locked */
1320 int
1321 StoreEntry::locked() const
1322 {
1323     if (lock_count)
1324         return 1;
1325
1326     /*
1327      * SPECIAL, PUBLIC entries should be "locked";
1328      * XXX: Their owner should lock them then instead of relying on this hack.
1329      */
1330     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1331         if (!EBIT_TEST(flags, KEY_PRIVATE))
1332             return 1;
1333
1334     return 0;
1335 }
1336
1337 bool
1338 StoreEntry::validLength() const
1339 {
1340     int64_t diff;
1341     const HttpReply *reply;
1342     assert(mem_obj != NULL);
1343     reply = getReply();
1344     debugs(20, 3, "storeEntryValidLength: Checking '" << getMD5Text() << "'");
1345     debugs(20, 5, "storeEntryValidLength:     object_len = " <<
1346            objectLen());
1347     debugs(20, 5, "storeEntryValidLength:         hdr_sz = " << reply->hdr_sz);
1348     debugs(20, 5, "storeEntryValidLength: content_length = " << reply->content_length);
1349
1350     if (reply->content_length < 0) {
1351         debugs(20, 5, "storeEntryValidLength: Unspecified content length: " << getMD5Text());
1352         return 1;
1353     }
1354
1355     if (reply->hdr_sz == 0) {
1356         debugs(20, 5, "storeEntryValidLength: Zero header size: " << getMD5Text());
1357         return 1;
1358     }
1359
1360     if (mem_obj->method == Http::METHOD_HEAD) {
1361         debugs(20, 5, "storeEntryValidLength: HEAD request: " << getMD5Text());
1362         return 1;
1363     }
1364
1365     if (reply->sline.status() == Http::scNotModified)
1366         return 1;
1367
1368     if (reply->sline.status() == Http::scNoContent)
1369         return 1;
1370
1371     diff = reply->hdr_sz + reply->content_length - objectLen();
1372
1373     if (diff == 0)
1374         return 1;
1375
1376     debugs(20, 3, "storeEntryValidLength: " << (diff < 0 ? -diff : diff)  << " bytes too " << (diff < 0 ? "big" : "small") <<"; '" << getMD5Text() << "'" );
1377
1378     return 0;
1379 }
1380
1381 static void
1382 storeRegisterWithCacheManager(void)
1383 {
1384     Mgr::RegisterAction("storedir", "Store Directory Stats", Store::Stats, 0, 1);
1385     Mgr::RegisterAction("store_io", "Store IO Interface Stats", &Mgr::StoreIoAction::Create, 0, 1);
1386     Mgr::RegisterAction("store_check_cachable_stats", "storeCheckCachable() Stats",
1387                         storeCheckCachableStats, 0, 1);
1388 }
1389
1390 void
1391 storeInit(void)
1392 {
1393     storeKeyInit();
1394     mem_policy = createRemovalPolicy(Config.memPolicy);
1395     storeDigestInit();
1396     storeLogOpen();
1397     eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1398     Store::Root().init();
1399     storeRebuildStart();
1400
1401     storeRegisterWithCacheManager();
1402 }
1403
1404 void
1405 storeConfigure(void)
1406 {
1407     Store::Root().updateLimits();
1408 }
1409
1410 bool
1411 StoreEntry::memoryCachable()
1412 {
1413     if (!checkCachable())
1414         return 0;
1415
1416     if (mem_obj == NULL)
1417         return 0;
1418
1419     if (mem_obj->data_hdr.size() == 0)
1420         return 0;
1421
1422     if (mem_obj->inmem_lo != 0)
1423         return 0;
1424
1425     if (!Config.onoff.memory_cache_first && swap_status == SWAPOUT_DONE && refcount == 1)
1426         return 0;
1427
1428     return 1;
1429 }
1430
1431 int
1432 StoreEntry::checkNegativeHit() const
1433 {
1434     if (!EBIT_TEST(flags, ENTRY_NEGCACHED))
1435         return 0;
1436
1437     if (expires <= squid_curtime)
1438         return 0;
1439
1440     if (store_status != STORE_OK)
1441         return 0;
1442
1443     return 1;
1444 }
1445
1446 /**
1447  * Set object for negative caching.
1448  * Preserves any expiry information given by the server.
1449  * In absence of proper expiry info it will set to expire immediately,
1450  * or with HTTP-violations enabled the configured negative-TTL is observed
1451  */
1452 void
1453 StoreEntry::negativeCache()
1454 {
1455     // XXX: should make the default for expires 0 instead of -1
1456     //      so we can distinguish "Expires: -1" from nothing.
1457     if (expires <= 0)
1458 #if USE_HTTP_VIOLATIONS
1459         expires = squid_curtime + Config.negativeTtl;
1460 #else
1461         expires = squid_curtime;
1462 #endif
1463     EBIT_SET(flags, ENTRY_NEGCACHED);
1464 }
1465
1466 void
1467 storeFreeMemory(void)
1468 {
1469     Store::FreeMemory();
1470 #if USE_CACHE_DIGESTS
1471     delete store_digest;
1472 #endif
1473     store_digest = NULL;
1474 }
1475
1476 int
1477 expiresMoreThan(time_t expires, time_t when)
1478 {
1479     if (expires < 0)            /* No Expires given */
1480         return 1;
1481
1482     return (expires > (squid_curtime + when));
1483 }
1484
1485 int
1486 StoreEntry::validToSend() const
1487 {
1488     if (EBIT_TEST(flags, RELEASE_REQUEST))
1489         return 0;
1490
1491     if (EBIT_TEST(flags, ENTRY_NEGCACHED))
1492         if (expires <= squid_curtime)
1493             return 0;
1494
1495     if (EBIT_TEST(flags, ENTRY_ABORTED))
1496         return 0;
1497
1498     // now check that the entry has a cache backing or is collapsed
1499     if (swap_filen > -1) // backed by a disk cache
1500         return 1;
1501
1502     if (swappingOut()) // will be backed by a disk cache
1503         return 1;
1504
1505     if (!mem_obj) // not backed by a memory cache and not collapsed
1506         return 0;
1507
1508     // StoreEntry::storeClientType() assumes DISK_CLIENT here, but there is no
1509     // disk cache backing that store_client constructor will assert. XXX: This
1510     // is wrong for range requests (that could feed off nibbled memory) and for
1511     // entries backed by the shared memory cache (that could, in theory, get
1512     // nibbled bytes from that cache, but there is no such "memoryIn" code).
1513     if (mem_obj->inmem_lo) // in memory cache, but got nibbled at
1514         return 0;
1515
1516     // The following check is correct but useless at this position. TODO: Move
1517     // it up when the shared memory cache can either replenish locally nibbled
1518     // bytes or, better, does not use local RAM copy at all.
1519     // if (mem_obj->memCache.index >= 0) // backed by a shared memory cache
1520     //    return 1;
1521
1522     return 1;
1523 }
1524
1525 bool
1526 StoreEntry::timestampsSet()
1527 {
1528     const HttpReply *reply = getReply();
1529     time_t served_date = reply->date;
1530     int age = reply->header.getInt(Http::HdrType::AGE);
1531     /* Compute the timestamp, mimicking RFC2616 section 13.2.3. */
1532     /* make sure that 0 <= served_date <= squid_curtime */
1533
1534     if (served_date < 0 || served_date > squid_curtime)
1535         served_date = squid_curtime;
1536
1537     /* Bug 1791:
1538      * If the returned Date: is more than 24 hours older than
1539      * the squid_curtime, then one of us needs to use NTP to set our
1540      * clock.  We'll pretend that our clock is right.
1541      */
1542     else if (served_date < (squid_curtime - 24 * 60 * 60) )
1543         served_date = squid_curtime;
1544
1545     /*
1546      * Compensate with Age header if origin server clock is ahead
1547      * of us and there is a cache in between us and the origin
1548      * server.  But DONT compensate if the age value is larger than
1549      * squid_curtime because it results in a negative served_date.
1550      */
1551     if (age > squid_curtime - served_date)
1552         if (squid_curtime > age)
1553             served_date = squid_curtime - age;
1554
1555     // compensate for Squid-to-server and server-to-Squid delays
1556     if (mem_obj && mem_obj->request) {
1557         const time_t request_sent =
1558             mem_obj->request->hier.peer_http_request_sent.tv_sec;
1559         if (0 < request_sent && request_sent < squid_curtime)
1560             served_date -= (squid_curtime - request_sent);
1561     }
1562
1563     time_t exp = 0;
1564     if (reply->expires > 0 && reply->date > -1)
1565         exp = served_date + (reply->expires - reply->date);
1566     else
1567         exp = reply->expires;
1568
1569     if (timestamp == served_date && expires == exp) {
1570         // if the reply lacks LMT, then we now know that our effective
1571         // LMT (i.e., timestamp) will stay the same, otherwise, old and
1572         // new modification times must match
1573         if (reply->last_modified < 0 || reply->last_modified == lastModified())
1574             return false; // nothing has changed
1575     }
1576
1577     expires = exp;
1578
1579     lastModified_ = reply->last_modified;
1580
1581     timestamp = served_date;
1582
1583     return true;
1584 }
1585
1586 void
1587 StoreEntry::registerAbort(STABH * cb, void *data)
1588 {
1589     assert(mem_obj);
1590     assert(mem_obj->abort.callback == NULL);
1591     mem_obj->abort.callback = cb;
1592     mem_obj->abort.data = cbdataReference(data);
1593 }
1594
1595 void
1596 StoreEntry::unregisterAbort()
1597 {
1598     assert(mem_obj);
1599     if (mem_obj->abort.callback) {
1600         mem_obj->abort.callback = NULL;
1601         cbdataReferenceDone(mem_obj->abort.data);
1602     }
1603 }
1604
1605 void
1606 StoreEntry::dump(int l) const
1607 {
1608     debugs(20, l, "StoreEntry->key: " << getMD5Text());
1609     debugs(20, l, "StoreEntry->next: " << next);
1610     debugs(20, l, "StoreEntry->mem_obj: " << mem_obj);
1611     debugs(20, l, "StoreEntry->timestamp: " << timestamp);
1612     debugs(20, l, "StoreEntry->lastref: " << lastref);
1613     debugs(20, l, "StoreEntry->expires: " << expires);
1614     debugs(20, l, "StoreEntry->lastModified_: " << lastModified_);
1615     debugs(20, l, "StoreEntry->swap_file_sz: " << swap_file_sz);
1616     debugs(20, l, "StoreEntry->refcount: " << refcount);
1617     debugs(20, l, "StoreEntry->flags: " << storeEntryFlags(this));
1618     debugs(20, l, "StoreEntry->swap_dirn: " << swap_dirn);
1619     debugs(20, l, "StoreEntry->swap_filen: " << swap_filen);
1620     debugs(20, l, "StoreEntry->lock_count: " << lock_count);
1621     debugs(20, l, "StoreEntry->mem_status: " << mem_status);
1622     debugs(20, l, "StoreEntry->ping_status: " << ping_status);
1623     debugs(20, l, "StoreEntry->store_status: " << store_status);
1624     debugs(20, l, "StoreEntry->swap_status: " << swap_status);
1625 }
1626
1627 /*
1628  * NOTE, this function assumes only two mem states
1629  */
1630 void
1631 StoreEntry::setMemStatus(mem_status_t new_status)
1632 {
1633     if (new_status == mem_status)
1634         return;
1635
1636     // are we using a shared memory cache?
1637     if (Config.memShared && IamWorkerProcess()) {
1638         // This method was designed to update replacement policy, not to
1639         // actually purge something from the memory cache (TODO: rename?).
1640         // Shared memory cache does not have a policy that needs updates.
1641         mem_status = new_status;
1642         return;
1643     }
1644
1645     assert(mem_obj != NULL);
1646
1647     if (new_status == IN_MEMORY) {
1648         assert(mem_obj->inmem_lo == 0);
1649
1650         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1651             debugs(20, 4, "not inserting special " << *this << " into policy");
1652         } else {
1653             mem_policy->Add(mem_policy, this, &mem_obj->repl);
1654             debugs(20, 4, "inserted " << *this << " key: " << getMD5Text());
1655         }
1656
1657         ++hot_obj_count; // TODO: maintain for the shared hot cache as well
1658     } else {
1659         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1660             debugs(20, 4, "not removing special " << *this << " from policy");
1661         } else {
1662             mem_policy->Remove(mem_policy, this, &mem_obj->repl);
1663             debugs(20, 4, "removed " << *this);
1664         }
1665
1666         --hot_obj_count;
1667     }
1668
1669     mem_status = new_status;
1670 }
1671
1672 const char *
1673 StoreEntry::url() const
1674 {
1675     if (mem_obj == NULL)
1676         return "[null_mem_obj]";
1677     else
1678         return mem_obj->storeId();
1679 }
1680
1681 MemObject *
1682 StoreEntry::makeMemObject()
1683 {
1684     if (!mem_obj)
1685         mem_obj = new MemObject();
1686     return mem_obj;
1687 }
1688
1689 void
1690 StoreEntry::createMemObject(const char *aUrl, const char *aLogUrl, const HttpRequestMethod &aMethod)
1691 {
1692     makeMemObject();
1693     mem_obj->setUris(aUrl, aLogUrl, aMethod);
1694 }
1695
1696 /** disable sending content to the clients.
1697  *
1698  * This just sets DELAY_SENDING.
1699  */
1700 void
1701 StoreEntry::buffer()
1702 {
1703     EBIT_SET(flags, DELAY_SENDING);
1704 }
1705
1706 /** flush any buffered content.
1707  *
1708  * This just clears DELAY_SENDING and Invokes the handlers
1709  * to begin sending anything that may be buffered.
1710  */
1711 void
1712 StoreEntry::flush()
1713 {
1714     if (EBIT_TEST(flags, DELAY_SENDING)) {
1715         EBIT_CLR(flags, DELAY_SENDING);
1716         invokeHandlers();
1717     }
1718 }
1719
1720 int64_t
1721 StoreEntry::objectLen() const
1722 {
1723     assert(mem_obj != NULL);
1724     return mem_obj->object_sz;
1725 }
1726
1727 int64_t
1728 StoreEntry::contentLen() const
1729 {
1730     assert(mem_obj != NULL);
1731     assert(getReply() != NULL);
1732     return objectLen() - getReply()->hdr_sz;
1733 }
1734
1735 HttpReply const *
1736 StoreEntry::getReply() const
1737 {
1738     return (mem_obj ? mem_obj->getReply().getRaw() : nullptr);
1739 }
1740
1741 void
1742 StoreEntry::reset()
1743 {
1744     assert (mem_obj);
1745     debugs(20, 3, url());
1746     mem_obj->reset();
1747     expires = lastModified_ = timestamp = -1;
1748 }
1749
1750 /*
1751  * storeFsInit
1752  *
1753  * This routine calls the SETUP routine for each fs type.
1754  * I don't know where the best place for this is, and I'm not going to shuffle
1755  * around large chunks of code right now (that can be done once its working.)
1756  */
1757 void
1758 storeFsInit(void)
1759 {
1760     storeReplSetup();
1761 }
1762
1763 /*
1764  * called to add another store removal policy module
1765  */
1766 void
1767 storeReplAdd(const char *type, REMOVALPOLICYCREATE * create)
1768 {
1769     int i;
1770
1771     /* find the number of currently known repl types */
1772     for (i = 0; storerepl_list && storerepl_list[i].typestr; ++i) {
1773         if (strcmp(storerepl_list[i].typestr, type) == 0) {
1774             debugs(20, DBG_IMPORTANT, "WARNING: Trying to load store replacement policy " << type << " twice.");
1775             return;
1776         }
1777     }
1778
1779     /* add the new type */
1780     storerepl_list = static_cast<storerepl_entry_t *>(xrealloc(storerepl_list, (i + 2) * sizeof(storerepl_entry_t)));
1781
1782     memset(&storerepl_list[i + 1], 0, sizeof(storerepl_entry_t));
1783
1784     storerepl_list[i].typestr = type;
1785
1786     storerepl_list[i].create = create;
1787 }
1788
1789 /*
1790  * Create a removal policy instance
1791  */
1792 RemovalPolicy *
1793 createRemovalPolicy(RemovalPolicySettings * settings)
1794 {
1795     storerepl_entry_t *r;
1796
1797     for (r = storerepl_list; r && r->typestr; ++r) {
1798         if (strcmp(r->typestr, settings->type) == 0)
1799             return r->create(settings->args);
1800     }
1801
1802     debugs(20, DBG_IMPORTANT, "ERROR: Unknown policy " << settings->type);
1803     debugs(20, DBG_IMPORTANT, "ERROR: Be sure to have set cache_replacement_policy");
1804     debugs(20, DBG_IMPORTANT, "ERROR:   and memory_replacement_policy in squid.conf!");
1805     fatalf("ERROR: Unknown policy %s\n", settings->type);
1806     return NULL;                /* NOTREACHED */
1807 }
1808
1809 #if 0
1810 void
1811 storeSwapFileNumberSet(StoreEntry * e, sfileno filn)
1812 {
1813     if (e->swap_file_number == filn)
1814         return;
1815
1816     if (filn < 0) {
1817         assert(-1 == filn);
1818         storeDirMapBitReset(e->swap_file_number);
1819         storeDirLRUDelete(e);
1820         e->swap_file_number = -1;
1821     } else {
1822         assert(-1 == e->swap_file_number);
1823         storeDirMapBitSet(e->swap_file_number = filn);
1824         storeDirLRUAdd(e);
1825     }
1826 }
1827
1828 #endif
1829
1830 void
1831 StoreEntry::storeErrorResponse(HttpReply *reply)
1832 {
1833     lock("StoreEntry::storeErrorResponse");
1834     buffer();
1835     replaceHttpReply(reply);
1836     flush();
1837     complete();
1838     negativeCache();
1839     releaseRequest();
1840     unlock("StoreEntry::storeErrorResponse");
1841 }
1842
1843 /*
1844  * Replace a store entry with
1845  * a new reply. This eats the reply.
1846  */
1847 void
1848 StoreEntry::replaceHttpReply(HttpReply *rep, bool andStartWriting)
1849 {
1850     debugs(20, 3, "StoreEntry::replaceHttpReply: " << url());
1851
1852     if (!mem_obj) {
1853         debugs(20, DBG_CRITICAL, "Attempt to replace object with no in-memory representation");
1854         return;
1855     }
1856
1857     mem_obj->replaceReply(HttpReplyPointer(rep));
1858
1859     if (andStartWriting)
1860         startWriting();
1861 }
1862
1863 void
1864 StoreEntry::startWriting()
1865 {
1866     /* TODO: when we store headers separately remove the header portion */
1867     /* TODO: mark the length of the headers ? */
1868     /* We ONLY want the headers */
1869
1870     assert (isEmpty());
1871     assert(mem_obj);
1872
1873     const HttpReply *rep = getReply();
1874     assert(rep);
1875
1876     buffer();
1877     rep->packHeadersInto(this);
1878     mem_obj->markEndOfReplyHeaders();
1879     EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
1880
1881     rep->body.packInto(this);
1882     flush();
1883 }
1884
1885 char const *
1886 StoreEntry::getSerialisedMetaData()
1887 {
1888     StoreMeta *tlv_list = storeSwapMetaBuild(this);
1889     int swap_hdr_sz;
1890     char *result = storeSwapMetaPack(tlv_list, &swap_hdr_sz);
1891     storeSwapTLVFree(tlv_list);
1892     assert (swap_hdr_sz >= 0);
1893     mem_obj->swap_hdr_sz = (size_t) swap_hdr_sz;
1894     return result;
1895 }
1896
1897 /**
1898  * Abandon the transient entry our worker has created if neither the shared
1899  * memory cache nor the disk cache wants to store it. Collapsed requests, if
1900  * any, should notice and use Plan B instead of getting stuck waiting for us
1901  * to start swapping the entry out.
1902  */
1903 void
1904 StoreEntry::transientsAbandonmentCheck()
1905 {
1906     if (mem_obj && !mem_obj->smpCollapsed && // this worker is responsible
1907             mem_obj->xitTable.index >= 0 && // other workers may be interested
1908             mem_obj->memCache.index < 0 && // rejected by the shared memory cache
1909             mem_obj->swapout.decision == MemObject::SwapOut::swImpossible) {
1910         debugs(20, 7, "cannot be shared: " << *this);
1911         if (!shutting_down) // Store::Root() is FATALly missing during shutdown
1912             Store::Root().transientsAbandon(*this);
1913     }
1914 }
1915
1916 void
1917 StoreEntry::memOutDecision(const bool)
1918 {
1919     transientsAbandonmentCheck();
1920 }
1921
1922 void
1923 StoreEntry::swapOutDecision(const MemObject::SwapOut::Decision &decision)
1924 {
1925     // Abandon our transient entry if neither shared memory nor disk wants it.
1926     assert(mem_obj);
1927     mem_obj->swapout.decision = decision;
1928     transientsAbandonmentCheck();
1929 }
1930
1931 void
1932 StoreEntry::trimMemory(const bool preserveSwappable)
1933 {
1934     /*
1935      * DPW 2007-05-09
1936      * Bug #1943.  We must not let go any data for IN_MEMORY
1937      * objects.  We have to wait until the mem_status changes.
1938      */
1939     if (mem_status == IN_MEMORY)
1940         return;
1941
1942     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1943         return; // cannot trim because we do not load them again
1944
1945     if (preserveSwappable)
1946         mem_obj->trimSwappable();
1947     else
1948         mem_obj->trimUnSwappable();
1949
1950     debugs(88, 7, *this << " inmem_lo=" << mem_obj->inmem_lo);
1951 }
1952
1953 bool
1954 StoreEntry::modifiedSince(const time_t ims, const int imslen) const
1955 {
1956     int object_length;
1957     const time_t mod_time = lastModified();
1958
1959     debugs(88, 3, "modifiedSince: '" << url() << "'");
1960
1961     debugs(88, 3, "modifiedSince: mod_time = " << mod_time);
1962
1963     if (mod_time < 0)
1964         return true;
1965
1966     /* Find size of the object */
1967     object_length = getReply()->content_length;
1968
1969     if (object_length < 0)
1970         object_length = contentLen();
1971
1972     if (mod_time > ims) {
1973         debugs(88, 3, "--> YES: entry newer than client");
1974         return true;
1975     } else if (mod_time < ims) {
1976         debugs(88, 3, "-->  NO: entry older than client");
1977         return false;
1978     } else if (imslen < 0) {
1979         debugs(88, 3, "-->  NO: same LMT, no client length");
1980         return false;
1981     } else if (imslen == object_length) {
1982         debugs(88, 3, "-->  NO: same LMT, same length");
1983         return false;
1984     } else {
1985         debugs(88, 3, "--> YES: same LMT, different length");
1986         return true;
1987     }
1988 }
1989
1990 bool
1991 StoreEntry::hasEtag(ETag &etag) const
1992 {
1993     if (const HttpReply *reply = getReply()) {
1994         etag = reply->header.getETag(Http::HdrType::ETAG);
1995         if (etag.str)
1996             return true;
1997     }
1998     return false;
1999 }
2000
2001 bool
2002 StoreEntry::hasIfMatchEtag(const HttpRequest &request) const
2003 {
2004     const String reqETags = request.header.getList(Http::HdrType::IF_MATCH);
2005     return hasOneOfEtags(reqETags, false);
2006 }
2007
2008 bool
2009 StoreEntry::hasIfNoneMatchEtag(const HttpRequest &request) const
2010 {
2011     const String reqETags = request.header.getList(Http::HdrType::IF_NONE_MATCH);
2012     // weak comparison is allowed only for HEAD or full-body GET requests
2013     const bool allowWeakMatch = !request.flags.isRanged &&
2014                                 (request.method == Http::METHOD_GET || request.method == Http::METHOD_HEAD);
2015     return hasOneOfEtags(reqETags, allowWeakMatch);
2016 }
2017
2018 /// whether at least one of the request ETags matches entity ETag
2019 bool
2020 StoreEntry::hasOneOfEtags(const String &reqETags, const bool allowWeakMatch) const
2021 {
2022     const ETag repETag = getReply()->header.getETag(Http::HdrType::ETAG);
2023     if (!repETag.str) {
2024         static SBuf asterisk("*", 1);
2025         return strListIsMember(&reqETags, asterisk, ',');
2026     }
2027
2028     bool matched = false;
2029     const char *pos = NULL;
2030     const char *item;
2031     int ilen;
2032     while (!matched && strListGetItem(&reqETags, ',', &item, &ilen, &pos)) {
2033         if (!strncmp(item, "*", ilen))
2034             matched = true;
2035         else {
2036             String str;
2037             str.append(item, ilen);
2038             ETag reqETag;
2039             if (etagParseInit(&reqETag, str.termedBuf())) {
2040                 matched = allowWeakMatch ? etagIsWeakEqual(repETag, reqETag) :
2041                           etagIsStrongEqual(repETag, reqETag);
2042             }
2043         }
2044     }
2045     return matched;
2046 }
2047
2048 Store::Disk &
2049 StoreEntry::disk() const
2050 {
2051     assert(0 <= swap_dirn && swap_dirn < Config.cacheSwap.n_configured);
2052     const RefCount<Store::Disk> &sd = INDEXSD(swap_dirn);
2053     assert(sd);
2054     return *sd;
2055 }
2056
2057 /*
2058  * return true if the entry is in a state where
2059  * it can accept more data (ie with write() method)
2060  */
2061 bool
2062 StoreEntry::isAccepting() const
2063 {
2064     if (STORE_PENDING != store_status)
2065         return false;
2066
2067     if (EBIT_TEST(flags, ENTRY_ABORTED))
2068         return false;
2069
2070     return true;
2071 }
2072
2073 const char *
2074 StoreEntry::describeTimestamps() const
2075 {
2076     LOCAL_ARRAY(char, buf, 256);
2077     snprintf(buf, 256, "LV:%-9d LU:%-9d LM:%-9d EX:%-9d",
2078              static_cast<int>(timestamp),
2079              static_cast<int>(lastref),
2080              static_cast<int>(lastModified_),
2081              static_cast<int>(expires));
2082     return buf;
2083 }
2084
2085 std::ostream &operator <<(std::ostream &os, const StoreEntry &e)
2086 {
2087     os << "e:";
2088
2089     if (e.mem_obj) {
2090         if (e.mem_obj->xitTable.index > -1)
2091             os << 't' << e.mem_obj->xitTable.index;
2092         if (e.mem_obj->memCache.index > -1)
2093             os << 'm' << e.mem_obj->memCache.index;
2094     }
2095     if (e.swap_filen > -1 || e.swap_dirn > -1)
2096         os << 'd' << e.swap_filen << '@' << e.swap_dirn;
2097
2098     os << '=';
2099
2100     // print only non-default status values, using unique letters
2101     if (e.mem_status != NOT_IN_MEMORY ||
2102             e.store_status != STORE_PENDING ||
2103             e.swap_status != SWAPOUT_NONE ||
2104             e.ping_status != PING_NONE) {
2105         if (e.mem_status != NOT_IN_MEMORY) os << 'm';
2106         if (e.store_status != STORE_PENDING) os << 's';
2107         if (e.swap_status != SWAPOUT_NONE) os << 'w' << e.swap_status;
2108         if (e.ping_status != PING_NONE) os << 'p' << e.ping_status;
2109     }
2110
2111     // print only set flags, using unique letters
2112     if (e.flags) {
2113         if (EBIT_TEST(e.flags, ENTRY_SPECIAL)) os << 'S';
2114         if (EBIT_TEST(e.flags, ENTRY_REVALIDATE_ALWAYS)) os << 'R';
2115         if (EBIT_TEST(e.flags, DELAY_SENDING)) os << 'P';
2116         if (EBIT_TEST(e.flags, RELEASE_REQUEST)) os << 'X';
2117         if (EBIT_TEST(e.flags, REFRESH_REQUEST)) os << 'F';
2118         if (EBIT_TEST(e.flags, ENTRY_REVALIDATE_STALE)) os << 'E';
2119         if (EBIT_TEST(e.flags, KEY_PRIVATE)) {
2120             os << 'I';
2121             if (e.shareableWhenPrivate)
2122                 os << 'H';
2123         }
2124         if (EBIT_TEST(e.flags, KEY_PRIVATE)) os << 'I';
2125         if (EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT)) os << 'W';
2126         if (EBIT_TEST(e.flags, ENTRY_NEGCACHED)) os << 'N';
2127         if (EBIT_TEST(e.flags, ENTRY_VALIDATED)) os << 'V';
2128         if (EBIT_TEST(e.flags, ENTRY_BAD_LENGTH)) os << 'L';
2129         if (EBIT_TEST(e.flags, ENTRY_ABORTED)) os << 'A';
2130     }
2131
2132     if (e.mem_obj && e.mem_obj->smpCollapsed)
2133         os << 'O';
2134
2135     return os << '/' << &e << '*' << e.locks();
2136 }
2137
2138 /* NullStoreEntry */
2139
2140 NullStoreEntry NullStoreEntry::_instance;
2141
2142 NullStoreEntry *
2143 NullStoreEntry::getInstance()
2144 {
2145     return &_instance;
2146 }
2147
2148 char const *
2149 NullStoreEntry::getMD5Text() const
2150 {
2151     return "N/A";
2152 }
2153
2154 void
2155 NullStoreEntry::operator delete(void*)
2156 {
2157     fatal ("Attempt to delete NullStoreEntry\n");
2158 }
2159
2160 char const *
2161 NullStoreEntry::getSerialisedMetaData()
2162 {
2163     return NULL;
2164 }
2165