src/store.cc

   1 /*
   2  * Copyright (C) 1996-2014 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_digest.h"
  36 #include "store_key_md5.h"
  37 #include "store_key_md5.h"
  38 #include "store_log.h"
  39 #include "store_rebuild.h"
  40 #include "StoreClient.h"
  41 #include "StoreIOState.h"
  42 #include "StoreMeta.h"
  43 #include "StrList.h"
  44 #include "swap_log_op.h"
  45 #include "SwapDir.h"
  46 #include "tools.h"
  47 #if USE_DELAY_POOLS
  48 #include "DelayPools.h"
  49 #endif
  50
  51 /** StoreEntry uses explicit new/delete operators, which set pool chunk size to 2MB
  52  * XXX: convert to MEMPROXY_CLASS() API
  53  */
  54 #include "mem/Pool.h"
  55
  56 #include <climits>
  57 #include <stack>
  58
  59 #define REBUILD_TIMESTAMP_DELTA_MAX 2
  60
  61 #define STORE_IN_MEM_BUCKETS            (229)
  62
  63 /** \todo Convert these string constants to enum string-arrays generated */
  64
  65 const char *memStatusStr[] = {
  66     "NOT_IN_MEMORY",
  67     "IN_MEMORY"
  68 };
  69
  70 const char *pingStatusStr[] = {
  71     "PING_NONE",
  72     "PING_WAITING",
  73     "PING_DONE"
  74 };
  75
  76 const char *storeStatusStr[] = {
  77     "STORE_OK",
  78     "STORE_PENDING"
  79 };
  80
  81 const char *swapStatusStr[] = {
  82     "SWAPOUT_NONE",
  83     "SWAPOUT_WRITING",
  84     "SWAPOUT_DONE"
  85 };
  86
  87 /*
  88  * This defines an repl type
  89  */
  90
  91 typedef struct _storerepl_entry storerepl_entry_t;
  92
  93 struct _storerepl_entry {
  94     const char *typestr;
  95     REMOVALPOLICYCREATE *create;
  96 };
  97
  98 static storerepl_entry_t *storerepl_list = NULL;
  99
 100 /*
 101  * local function prototypes
 102  */
 103 static int getKeyCounter(void);
 104 static OBJH storeCheckCachableStats;
 105 static EVH storeLateRelease;
 106
 107 /*
 108  * local variables
 109  */
 110 static std::stack<StoreEntry*> LateReleaseStack;
 111 MemAllocator *StoreEntry::pool = NULL;
 112
 113 StorePointer Store::CurrentRoot = NULL;
 114
 115 void
 116 Store::Root(Store * aRoot)
 117 {
 118     CurrentRoot = aRoot;
 119 }
 120
 121 void
 122 Store::Root(StorePointer aRoot)
 123 {
 124     Root(aRoot.getRaw());
 125 }
 126
 127 void
 128 Store::Stats(StoreEntry * output)
 129 {
 130     assert (output);
 131     Root().stat(*output);
 132 }
 133
 134 void
 135 Store::create()
 136 {}
 137
 138 void
 139 Store::diskFull()
 140 {}
 141
 142 void
 143 Store::sync()
 144 {}
 145
 146 void
 147 Store::unlink (StoreEntry &anEntry)
 148 {
 149     fatal("Store::unlink on invalid Store\n");
 150 }
 151
 152 void *
 153 StoreEntry::operator new (size_t bytecount)
 154 {
 155     assert (bytecount == sizeof (StoreEntry));
 156
 157     if (!pool) {
 158         pool = memPoolCreate ("StoreEntry", bytecount);
 159         pool->setChunkSize(2048 * 1024);
 160     }
 161
 162     return pool->alloc();
 163 }
 164
 165 void
 166 StoreEntry::operator delete (void *address)
 167 {
 168     pool->freeOne(address);
 169 }
 170
 171 void
 172 StoreEntry::makePublic()
 173 {
 174     /* This object can be cached for a long time */
 175
 176     if (!EBIT_TEST(flags, RELEASE_REQUEST))
 177         setPublicKey();
 178 }
 179
 180 void
 181 StoreEntry::makePrivate()
 182 {
 183     /* This object should never be cached at all */
 184     expireNow();
 185     releaseRequest(); /* delete object when not used */
 186 }
 187
 188 void
 189 StoreEntry::cacheNegatively()
 190 {
 191     /* This object may be negatively cached */
 192     negativeCache();
 193     makePublic();
 194 }
 195
 196 size_t
 197 StoreEntry::inUseCount()
 198 {
 199     if (!pool)
 200         return 0;
 201     return pool->getInUseCount();
 202 }
 203
 204 const char *
 205 StoreEntry::getMD5Text() const
 206 {
 207     return storeKeyText((const cache_key *)key);
 208 }
 209
 210 #include "comm.h"
 211
 212 void
 213 StoreEntry::DeferReader(void *theContext, CommRead const &aRead)
 214 {
 215     StoreEntry *anEntry = (StoreEntry *)theContext;
 216     anEntry->delayAwareRead(aRead.conn,
 217                             aRead.buf,
 218                             aRead.len,
 219                             aRead.callback);
 220 }
 221
 222 void
 223 StoreEntry::delayAwareRead(const Comm::ConnectionPointer &conn, char *buf, int len, AsyncCall::Pointer callback)
 224 {
 225     size_t amountToRead = bytesWanted(Range<size_t>(0, len));
 226     /* sketch: readdeferer* = getdeferer.
 227      * ->deferRead (fd, buf, len, callback, DelayAwareRead, this)
 228      */
 229
 230     if (amountToRead == 0) {
 231         assert (mem_obj);
 232         /* read ahead limit */
 233         /* Perhaps these two calls should both live in MemObject */
 234 #if USE_DELAY_POOLS
 235         if (!mem_obj->readAheadPolicyCanRead()) {
 236 #endif
 237             mem_obj->delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 238             return;
 239 #if USE_DELAY_POOLS
 240         }
 241
 242         /* delay id limit */
 243         mem_obj->mostBytesAllowed().delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 244         return;
 245
 246 #endif
 247
 248     }
 249
 250     if (fd_table[conn->fd].closing()) {
 251         // Readers must have closing callbacks if they want to be notified. No
 252         // readers appeared to care around 2009/12/14 as they skipped reading
 253         // for other reasons. Closing may already be true at the delyaAwareRead
 254         // call time or may happen while we wait after delayRead() above.
 255         debugs(20, 3, HERE << "wont read from closing " << conn << " for " <<
 256                callback);
 257         return; // the read callback will never be called
 258     }
 259
 260     comm_read(conn, buf, amountToRead, callback);
 261 }
 262
 263 size_t
 264 StoreEntry::bytesWanted (Range<size_t> const aRange, bool ignoreDelayPools) const
 265 {
 266     if (mem_obj == NULL)
 267         return aRange.end;
 268
 269 #if URL_CHECKSUM_DEBUG
 270
 271     mem_obj->checkUrlChecksum();
 272
 273 #endif
 274
 275     if (!mem_obj->readAheadPolicyCanRead())
 276         return 0;
 277
 278     return mem_obj->mostBytesWanted(aRange.end, ignoreDelayPools);
 279 }
 280
 281 bool
 282 StoreEntry::checkDeferRead(int fd) const
 283 {
 284     return (bytesWanted(Range<size_t>(0,INT_MAX)) == 0);
 285 }
 286
 287 void
 288 StoreEntry::setNoDelay (bool const newValue)
 289 {
 290     if (mem_obj)
 291         mem_obj->setNoDelay(newValue);
 292 }
 293
 294 // XXX: Type names mislead. STORE_DISK_CLIENT actually means that we should
 295 //      open swapin file, aggressively trim memory, and ignore read-ahead gap.
 296 //      It does not mean we will read from disk exclusively (or at all!).
 297 // XXX: May create STORE_DISK_CLIENT with no disk caching configured.
 298 // XXX: Collapsed clients cannot predict their type.
 299 store_client_t
 300 StoreEntry::storeClientType() const
 301 {
 302     /* The needed offset isn't in memory
 303      * XXX TODO: this is wrong for range requests
 304      * as the needed offset may *not* be 0, AND
 305      * offset 0 in the memory object is the HTTP headers.
 306      */
 307
 308     assert(mem_obj);
 309
 310     if (mem_obj->inmem_lo)
 311         return STORE_DISK_CLIENT;
 312
 313     if (EBIT_TEST(flags, ENTRY_ABORTED)) {
 314         /* I don't think we should be adding clients to aborted entries */
 315         debugs(20, DBG_IMPORTANT, "storeClientType: adding to ENTRY_ABORTED entry");
 316         return STORE_MEM_CLIENT;
 317     }
 318
 319     if (store_status == STORE_OK) {
 320         /* the object has completed. */
 321
 322         if (mem_obj->inmem_lo == 0 && !isEmpty()) {
 323             if (swap_status == SWAPOUT_DONE) {
 324                 debugs(20,7, HERE << mem_obj << " lo: " << mem_obj->inmem_lo << " hi: " << mem_obj->endOffset() << " size: " << mem_obj->object_sz);
 325                 if (mem_obj->endOffset() == mem_obj->object_sz) {
 326                     /* hot object fully swapped in (XXX: or swapped out?) */
 327                     return STORE_MEM_CLIENT;
 328                 }
 329             } else {
 330                 /* Memory-only, or currently being swapped out */
 331                 return STORE_MEM_CLIENT;
 332             }
 333         }
 334         return STORE_DISK_CLIENT;
 335     }
 336
 337     /* here and past, entry is STORE_PENDING */
 338     /*
 339      * If this is the first client, let it be the mem client
 340      */
 341     if (mem_obj->nclients == 1)
 342         return STORE_MEM_CLIENT;
 343
 344     /*
 345      * If there is no disk file to open yet, we must make this a
 346      * mem client.  If we can't open the swapin file before writing
 347      * to the client, there is no guarantee that we will be able
 348      * to open it later when we really need it.
 349      */
 350     if (swap_status == SWAPOUT_NONE)
 351         return STORE_MEM_CLIENT;
 352
 353     /*
 354      * otherwise, make subsequent clients read from disk so they
 355      * can not delay the first, and vice-versa.
 356      */
 357     return STORE_DISK_CLIENT;
 358 }
 359
 360 StoreEntry::StoreEntry() :
 361     mem_obj(NULL),
 362     timestamp(-1),
 363     lastref(-1),
 364     expires(-1),
 365     lastmod(-1),
 366     swap_file_sz(0),
 367     refcount(0),
 368     flags(0),
 369     swap_filen(-1),
 370     swap_dirn(-1),
 371     mem_status(NOT_IN_MEMORY),
 372     ping_status(PING_NONE),
 373     store_status(STORE_PENDING),
 374     swap_status(SWAPOUT_NONE),
 375     lock_count(0)
 376 {
 377     debugs(20, 5, "StoreEntry constructed, this=" << this);
 378 }
 379
 380 StoreEntry::~StoreEntry()
 381 {
 382     debugs(20, 5, "StoreEntry destructed, this=" << this);
 383 }
 384
 385 #if USE_ADAPTATION
 386 void
 387 StoreEntry::deferProducer(const AsyncCall::Pointer &producer)
 388 {
 389     if (!deferredProducer)
 390         deferredProducer = producer;
 391     else
 392         debugs(20, 5, HERE << "Deferred producer call is allready set to: " <<
 393                *deferredProducer << ", requested call: " << *producer);
 394 }
 395
 396 void
 397 StoreEntry::kickProducer()
 398 {
 399     if (deferredProducer != NULL) {
 400         ScheduleCallHere(deferredProducer);
 401         deferredProducer = NULL;
 402     }
 403 }
 404 #endif
 405
 406 void
 407 StoreEntry::destroyMemObject()
 408 {
 409     debugs(20, 3, HERE << "destroyMemObject " << mem_obj);
 410
 411     if (MemObject *mem = mem_obj) {
 412         // Store::Root() is FATALly missing during shutdown
 413         if (mem->xitTable.index >= 0 && !shutting_down)
 414             Store::Root().transientsDisconnect(*mem);
 415         if (mem->memCache.index >= 0 && !shutting_down)
 416             Store::Root().memoryDisconnect(*this);
 417
 418         setMemStatus(NOT_IN_MEMORY);
 419         mem_obj = NULL;
 420         delete mem;
 421     }
 422 }
 423
 424 void
 425 destroyStoreEntry(void *data)
 426 {
 427     debugs(20, 3, HERE << "destroyStoreEntry: destroying " <<  data);
 428     StoreEntry *e = static_cast<StoreEntry *>(static_cast<hash_link *>(data));
 429     assert(e != NULL);
 430
 431     if (e == NullStoreEntry::getInstance())
 432         return;
 433
 434     // Store::Root() is FATALly missing during shutdown
 435     if (e->swap_filen >= 0 && !shutting_down) {
 436         SwapDir &sd = dynamic_cast<SwapDir&>(*e->store());
 437         sd.disconnect(*e);
 438     }
 439
 440     e->destroyMemObject();
 441
 442     e->hashDelete();
 443
 444     assert(e->key == NULL);
 445
 446     delete e;
 447 }
 448
 449 /* ----- INTERFACE BETWEEN STORAGE MANAGER AND HASH TABLE FUNCTIONS --------- */
 450
 451 void
 452 StoreEntry::hashInsert(const cache_key * someKey)
 453 {
 454     debugs(20, 3, "StoreEntry::hashInsert: Inserting Entry " << *this << " key '" << storeKeyText(someKey) << "'");
 455     key = storeKeyDup(someKey);
 456     hash_join(store_table, this);
 457 }
 458
 459 void
 460 StoreEntry::hashDelete()
 461 {
 462     if (key) { // some test cases do not create keys and do not hashInsert()
 463         hash_remove_link(store_table, this);
 464         storeKeyFree((const cache_key *)key);
 465         key = NULL;
 466     }
 467 }
 468
 469 /* -------------------------------------------------------------------------- */
 470
 471 /* get rid of memory copy of the object */
 472 void
 473 StoreEntry::purgeMem()
 474 {
 475     if (mem_obj == NULL)
 476         return;
 477
 478     debugs(20, 3, "StoreEntry::purgeMem: Freeing memory-copy of " << getMD5Text());
 479
 480     Store::Root().memoryUnlink(*this);
 481
 482     if (swap_status != SWAPOUT_DONE)
 483         release();
 484 }
 485
 486 void
 487 StoreEntry::lock(const char *context)
 488 {
 489     ++lock_count;
 490     debugs(20, 3, context << " locked key " << getMD5Text() << ' ' << *this);
 491 }
 492
 493 void
 494 StoreEntry::touch()
 495 {
 496     lastref = squid_curtime;
 497     Store::Root().reference(*this);
 498 }
 499
 500 void
 501 StoreEntry::setReleaseFlag()
 502 {
 503     if (EBIT_TEST(flags, RELEASE_REQUEST))
 504         return;
 505
 506     debugs(20, 3, "StoreEntry::setReleaseFlag: '" << getMD5Text() << "'");
 507
 508     EBIT_SET(flags, RELEASE_REQUEST);
 509
 510     Store::Root().markForUnlink(*this);
 511 }
 512
 513 void
 514 StoreEntry::releaseRequest()
 515 {
 516     if (EBIT_TEST(flags, RELEASE_REQUEST))
 517         return;
 518
 519     setReleaseFlag(); // makes validToSend() false, preventing future hits
 520
 521     setPrivateKey();
 522 }
 523
 524 int
 525 StoreEntry::unlock(const char *context)
 526 {
 527     debugs(20, 3, (context ? context : "somebody") <<
 528            " unlocking key " << getMD5Text() << ' ' << *this);
 529     assert(lock_count > 0);
 530     --lock_count;
 531
 532     if (lock_count)
 533         return (int) lock_count;
 534
 535     if (store_status == STORE_PENDING)
 536         setReleaseFlag();
 537
 538     assert(storePendingNClients(this) == 0);
 539
 540     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 541         this->release();
 542         return 0;
 543     }
 544
 545     if (EBIT_TEST(flags, KEY_PRIVATE))
 546         debugs(20, DBG_IMPORTANT, "WARNING: " << __FILE__ << ":" << __LINE__ << ": found KEY_PRIVATE");
 547
 548     Store::Root().handleIdleEntry(*this); // may delete us
 549     return 0;
 550 }
 551
 552 void
 553 StoreEntry::getPublicByRequestMethod  (StoreClient *aClient, HttpRequest * request, const HttpRequestMethod& method)
 554 {
 555     assert (aClient);
 556     StoreEntry *result = storeGetPublicByRequestMethod( request, method);
 557
 558     if (!result)
 559         aClient->created (NullStoreEntry::getInstance());
 560     else
 561         aClient->created (result);
 562 }
 563
 564 void
 565 StoreEntry::getPublicByRequest (StoreClient *aClient, HttpRequest * request)
 566 {
 567     assert (aClient);
 568     StoreEntry *result = storeGetPublicByRequest (request);
 569
 570     if (!result)
 571         result = NullStoreEntry::getInstance();
 572
 573     aClient->created (result);
 574 }
 575
 576 void
 577 StoreEntry::getPublic (StoreClient *aClient, const char *uri, const HttpRequestMethod& method)
 578 {
 579     assert (aClient);
 580     StoreEntry *result = storeGetPublic (uri, method);
 581
 582     if (!result)
 583         result = NullStoreEntry::getInstance();
 584
 585     aClient->created (result);
 586 }
 587
 588 StoreEntry *
 589 storeGetPublic(const char *uri, const HttpRequestMethod& method)
 590 {
 591     return Store::Root().get(storeKeyPublic(uri, method));
 592 }
 593
 594 StoreEntry *
 595 storeGetPublicByRequestMethod(HttpRequest * req, const HttpRequestMethod& method)
 596 {
 597     return Store::Root().get(storeKeyPublicByRequestMethod(req, method));
 598 }
 599
 600 StoreEntry *
 601 storeGetPublicByRequest(HttpRequest * req)
 602 {
 603     StoreEntry *e = storeGetPublicByRequestMethod(req, req->method);
 604
 605     if (e == NULL && req->method == Http::METHOD_HEAD)
 606         /* We can generate a HEAD reply from a cached GET object */
 607         e = storeGetPublicByRequestMethod(req, Http::METHOD_GET);
 608
 609     return e;
 610 }
 611
 612 static int
 613 getKeyCounter(void)
 614 {
 615     static int key_counter = 0;
 616
 617     if (++key_counter < 0)
 618         key_counter = 1;
 619
 620     return key_counter;
 621 }
 622
 623 /* RBC 20050104 AFAICT this should become simpler:
 624  * rather than reinserting with a special key it should be marked
 625  * as 'released' and then cleaned up when refcounting indicates.
 626  * the StoreHashIndex could well implement its 'released' in the
 627  * current manner.
 628  * Also, clean log writing should skip over ia,t
 629  * Otherwise, we need a 'remove from the index but not the store
 630  * concept'.
 631  */
 632 void
 633 StoreEntry::setPrivateKey()
 634 {
 635     const cache_key *newkey;
 636
 637     if (key && EBIT_TEST(flags, KEY_PRIVATE))
 638         return;                 /* is already private */
 639
 640     if (key) {
 641         setReleaseFlag(); // will markForUnlink(); all caches/workers will know
 642
 643         // TODO: move into SwapDir::markForUnlink() already called by Root()
 644         if (swap_filen > -1)
 645             storeDirSwapLog(this, SWAP_LOG_DEL);
 646
 647         hashDelete();
 648     }
 649
 650     if (mem_obj && mem_obj->hasUris()) {
 651         mem_obj->id = getKeyCounter();
 652         newkey = storeKeyPrivate(mem_obj->storeId(), mem_obj->method, mem_obj->id);
 653     } else {
 654         newkey = storeKeyPrivate("JUNK", Http::METHOD_NONE, getKeyCounter());
 655     }
 656
 657     assert(hash_lookup(store_table, newkey) == NULL);
 658     EBIT_SET(flags, KEY_PRIVATE);
 659     hashInsert(newkey);
 660 }
 661
 662 void
 663 StoreEntry::setPublicKey()
 664 {
 665     const cache_key *newkey;
 666
 667     if (key && !EBIT_TEST(flags, KEY_PRIVATE))
 668         return;                 /* is already public */
 669
 670     assert(mem_obj);
 671
 672     /*
 673      * We can't make RELEASE_REQUEST objects public.  Depending on
 674      * when RELEASE_REQUEST gets set, we might not be swapping out
 675      * the object.  If we're not swapping out, then subsequent
 676      * store clients won't be able to access object data which has
 677      * been freed from memory.
 678      *
 679      * If RELEASE_REQUEST is set, setPublicKey() should not be called.
 680      */
 681 #if MORE_DEBUG_OUTPUT
 682
 683     if (EBIT_TEST(flags, RELEASE_REQUEST))
 684         debugs(20, DBG_IMPORTANT, "assertion failed: RELEASE key " << key << ", url " << mem_obj->url);
 685
 686 #endif
 687
 688     assert(!EBIT_TEST(flags, RELEASE_REQUEST));
 689
 690     if (mem_obj->request) {
 691         HttpRequest *request = mem_obj->request;
 692
 693         if (!mem_obj->vary_headers) {
 694             /* First handle the case where the object no longer varies */
 695             safe_free(request->vary_headers);
 696         } else {
 697             if (request->vary_headers && strcmp(request->vary_headers, mem_obj->vary_headers) != 0) {
 698                 /* Oops.. the variance has changed. Kill the base object
 699                  * to record the new variance key
 700                  */
 701                 safe_free(request->vary_headers);       /* free old "bad" variance key */
 702                 if (StoreEntry *pe = storeGetPublic(mem_obj->storeId(), mem_obj->method))
 703                     pe->release();
 704             }
 705
 706             /* Make sure the request knows the variance status */
 707             if (!request->vary_headers) {
 708                 const char *vary = httpMakeVaryMark(request, mem_obj->getReply());
 709
 710                 if (vary)
 711                     request->vary_headers = xstrdup(vary);
 712             }
 713         }
 714
 715         // TODO: storeGetPublic() calls below may create unlocked entries.
 716         // We should add/use storeHas() API or lock/unlock those entries.
 717         if (mem_obj->vary_headers && !storeGetPublic(mem_obj->storeId(), mem_obj->method)) {
 718             /* Create "vary" base object */
 719             String vary;
 720             StoreEntry *pe = storeCreateEntry(mem_obj->storeId(), mem_obj->logUri(), request->flags, request->method);
 721             /* We are allowed to do this typecast */
 722             HttpReply *rep = new HttpReply;
 723             rep->setHeaders(Http::scOkay, "Internal marker object", "x-squid-internal/vary", -1, -1, squid_curtime + 100000);
 724             vary = mem_obj->getReply()->header.getList(HDR_VARY);
 725
 726             if (vary.size()) {
 727                 /* Again, we own this structure layout */
 728                 rep->header.putStr(HDR_VARY, vary.termedBuf());
 729                 vary.clean();
 730             }
 731
 732 #if X_ACCELERATOR_VARY
 733             vary = mem_obj->getReply()->header.getList(HDR_X_ACCELERATOR_VARY);
 734
 735             if (vary.size() > 0) {
 736                 /* Again, we own this structure layout */
 737                 rep->header.putStr(HDR_X_ACCELERATOR_VARY, vary.termedBuf());
 738                 vary.clean();
 739             }
 740
 741 #endif
 742             pe->replaceHttpReply(rep, false); // no write until key is public
 743
 744             pe->timestampsSet();
 745
 746             pe->makePublic();
 747
 748             pe->startWriting(); // after makePublic()
 749
 750             pe->complete();
 751
 752             pe->unlock("StoreEntry::setPublicKey+Vary");
 753         }
 754
 755         newkey = storeKeyPublicByRequest(mem_obj->request);
 756     } else
 757         newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 758
 759     if (StoreEntry *e2 = (StoreEntry *)hash_lookup(store_table, newkey)) {
 760         debugs(20, 3, "Making old " << *e2 << " private.");
 761         e2->setPrivateKey();
 762         e2->release();
 763
 764         if (mem_obj->request)
 765             newkey = storeKeyPublicByRequest(mem_obj->request);
 766         else
 767             newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 768     }
 769
 770     if (key)
 771         hashDelete();
 772
 773     EBIT_CLR(flags, KEY_PRIVATE);
 774
 775     hashInsert(newkey);
 776
 777     if (swap_filen > -1)
 778         storeDirSwapLog(this, SWAP_LOG_ADD);
 779 }
 780
 781 StoreEntry *
 782 storeCreatePureEntry(const char *url, const char *log_url, const RequestFlags &flags, const HttpRequestMethod& method)
 783 {
 784     StoreEntry *e = NULL;
 785     debugs(20, 3, "storeCreateEntry: '" << url << "'");
 786
 787     e = new StoreEntry();
 788     e->makeMemObject();
 789     e->mem_obj->setUris(url, log_url, method);
 790
 791     if (flags.cachable) {
 792         EBIT_CLR(e->flags, RELEASE_REQUEST);
 793     } else {
 794         e->releaseRequest();
 795     }
 796
 797     e->store_status = STORE_PENDING;
 798     e->refcount = 0;
 799     e->lastref = squid_curtime;
 800     e->timestamp = -1;          /* set in StoreEntry::timestampsSet() */
 801     e->ping_status = PING_NONE;
 802     EBIT_SET(e->flags, ENTRY_VALIDATED);
 803     return e;
 804 }
 805
 806 StoreEntry *
 807 storeCreateEntry(const char *url, const char *logUrl, const RequestFlags &flags, const HttpRequestMethod& method)
 808 {
 809     StoreEntry *e = storeCreatePureEntry(url, logUrl, flags, method);
 810     e->lock("storeCreateEntry");
 811
 812     if (neighbors_do_private_keys || !flags.hierarchical)
 813         e->setPrivateKey();
 814     else
 815         e->setPublicKey();
 816
 817     return e;
 818 }
 819
 820 /* Mark object as expired */
 821 void
 822 StoreEntry::expireNow()
 823 {
 824     debugs(20, 3, "StoreEntry::expireNow: '" << getMD5Text() << "'");
 825     expires = squid_curtime;
 826 }
 827
 828 void
 829 StoreEntry::write (StoreIOBuffer writeBuffer)
 830 {
 831     assert(mem_obj != NULL);
 832     /* This assert will change when we teach the store to update */
 833     PROF_start(StoreEntry_write);
 834     assert(store_status == STORE_PENDING);
 835
 836     // XXX: caller uses content offset, but we also store headers
 837     if (const HttpReply *reply = mem_obj->getReply())
 838         writeBuffer.offset += reply->hdr_sz;
 839
 840     debugs(20, 5, "storeWrite: writing " << writeBuffer.length << " bytes for '" << getMD5Text() << "'");
 841     PROF_stop(StoreEntry_write);
 842     storeGetMemSpace(writeBuffer.length);
 843     mem_obj->write(writeBuffer);
 844
 845     if (!EBIT_TEST(flags, DELAY_SENDING))
 846         invokeHandlers();
 847 }
 848
 849 /* Append incoming data from a primary server to an entry. */
 850 void
 851 StoreEntry::append(char const *buf, int len)
 852 {
 853     assert(mem_obj != NULL);
 854     assert(len >= 0);
 855     assert(store_status == STORE_PENDING);
 856
 857     StoreIOBuffer tempBuffer;
 858     tempBuffer.data = (char *)buf;
 859     tempBuffer.length = len;
 860     /*
 861      * XXX sigh, offset might be < 0 here, but it gets "corrected"
 862      * later.  This offset crap is such a mess.
 863      */
 864     tempBuffer.offset = mem_obj->endOffset() - (getReply() ? getReply()->hdr_sz : 0);
 865     write(tempBuffer);
 866 }
 867
 868 void
 869 storeAppendPrintf(StoreEntry * e, const char *fmt,...)
 870 {
 871     va_list args;
 872     va_start(args, fmt);
 873
 874     storeAppendVPrintf(e, fmt, args);
 875     va_end(args);
 876 }
 877
 878 /* used be storeAppendPrintf and Packer */
 879 void
 880 storeAppendVPrintf(StoreEntry * e, const char *fmt, va_list vargs)
 881 {
 882     LOCAL_ARRAY(char, buf, 4096);
 883     buf[0] = '\0';
 884     vsnprintf(buf, 4096, fmt, vargs);
 885     e->append(buf, strlen(buf));
 886 }
 887
 888 struct _store_check_cachable_hist {
 889
 890     struct {
 891         int non_get;
 892         int not_entry_cachable;
 893         int wrong_content_length;
 894         int negative_cached;
 895         int too_big;
 896         int too_small;
 897         int private_key;
 898         int too_many_open_files;
 899         int too_many_open_fds;
 900         int missing_parts;
 901     } no;
 902
 903     struct {
 904         int Default;
 905     } yes;
 906 } store_check_cachable_hist;
 907
 908 int
 909 storeTooManyDiskFilesOpen(void)
 910 {
 911     if (Config.max_open_disk_fds == 0)
 912         return 0;
 913
 914     if (store_open_disk_fd > Config.max_open_disk_fds)
 915         return 1;
 916
 917     return 0;
 918 }
 919
 920 int
 921 StoreEntry::checkTooSmall()
 922 {
 923     if (EBIT_TEST(flags, ENTRY_SPECIAL))
 924         return 0;
 925
 926     if (STORE_OK == store_status)
 927         if (mem_obj->object_sz >= 0 &&
 928                 mem_obj->object_sz < Config.Store.minObjectSize)
 929             return 1;
 930     if (getReply()->content_length > -1)
 931         if (getReply()->content_length < Config.Store.minObjectSize)
 932             return 1;
 933     return 0;
 934 }
 935
 936 bool
 937 StoreEntry::checkTooBig() const
 938 {
 939     if (mem_obj->endOffset() > store_maxobjsize)
 940         return true;
 941
 942     if (getReply()->content_length < 0)
 943         return false;
 944
 945     return (getReply()->content_length > store_maxobjsize);
 946 }
 947
 948 // TODO: move "too many open..." checks outside -- we are called too early/late
 949 bool
 950 StoreEntry::checkCachable()
 951 {
 952     // XXX: This method is used for both memory and disk caches, but some
 953     // checks are specific to disk caches. Move them to mayStartSwapOut().
 954
 955     // XXX: This method may be called several times, sometimes with different
 956     // outcomes, making store_check_cachable_hist counters misleading.
 957
 958     // check this first to optimize handling of repeated calls for uncachables
 959     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 960         debugs(20, 2, "StoreEntry::checkCachable: NO: not cachable");
 961         ++store_check_cachable_hist.no.not_entry_cachable; // TODO: rename?
 962         return 0; // avoid rerequesting release below
 963     }
 964
 965 #if CACHE_ALL_METHODS
 966
 967     if (mem_obj->method != Http::METHOD_GET) {
 968         debugs(20, 2, "StoreEntry::checkCachable: NO: non-GET method");
 969         ++store_check_cachable_hist.no.non_get;
 970     } else
 971 #endif
 972         if (store_status == STORE_OK && EBIT_TEST(flags, ENTRY_BAD_LENGTH)) {
 973             debugs(20, 2, "StoreEntry::checkCachable: NO: wrong content-length");
 974             ++store_check_cachable_hist.no.wrong_content_length;
 975         } else if (EBIT_TEST(flags, ENTRY_NEGCACHED)) {
 976             debugs(20, 3, "StoreEntry::checkCachable: NO: negative cached");
 977             ++store_check_cachable_hist.no.negative_cached;
 978             return 0;           /* avoid release call below */
 979         } else if (!mem_obj || !getReply()) {
 980             // XXX: In bug 4131, we forgetHit() without mem_obj, so we need
 981             // this segfault protection, but how can we get such a HIT?
 982             debugs(20, 2, "StoreEntry::checkCachable: NO: missing parts: " << *this);
 983             ++store_check_cachable_hist.no.missing_parts;
 984         } else if (checkTooBig()) {
 985             debugs(20, 2, "StoreEntry::checkCachable: NO: too big");
 986             ++store_check_cachable_hist.no.too_big;
 987         } else if (checkTooSmall()) {
 988             debugs(20, 2, "StoreEntry::checkCachable: NO: too small");
 989             ++store_check_cachable_hist.no.too_small;
 990         } else if (EBIT_TEST(flags, KEY_PRIVATE)) {
 991             debugs(20, 3, "StoreEntry::checkCachable: NO: private key");
 992             ++store_check_cachable_hist.no.private_key;
 993         } else if (swap_status != SWAPOUT_NONE) {
 994             /*
 995              * here we checked the swap_status because the remaining
 996              * cases are only relevant only if we haven't started swapping
 997              * out the object yet.
 998              */
 999             return 1;
1000         } else if (storeTooManyDiskFilesOpen()) {
1001             debugs(20, 2, "StoreEntry::checkCachable: NO: too many disk files open");
1002             ++store_check_cachable_hist.no.too_many_open_files;
1003         } else if (fdNFree() < RESERVED_FD) {
1004             debugs(20, 2, "StoreEntry::checkCachable: NO: too many FD's open");
1005             ++store_check_cachable_hist.no.too_many_open_fds;
1006         } else {
1007             ++store_check_cachable_hist.yes.Default;
1008             return 1;
1009         }
1010
1011     releaseRequest();
1012     return 0;
1013 }
1014
1015 void
1016 storeCheckCachableStats(StoreEntry *sentry)
1017 {
1018     storeAppendPrintf(sentry, "Category\t Count\n");
1019
1020 #if CACHE_ALL_METHODS
1021
1022     storeAppendPrintf(sentry, "no.non_get\t%d\n",
1023                       store_check_cachable_hist.no.non_get);
1024 #endif
1025
1026     storeAppendPrintf(sentry, "no.not_entry_cachable\t%d\n",
1027                       store_check_cachable_hist.no.not_entry_cachable);
1028     storeAppendPrintf(sentry, "no.wrong_content_length\t%d\n",
1029                       store_check_cachable_hist.no.wrong_content_length);
1030     storeAppendPrintf(sentry, "no.negative_cached\t%d\n",
1031                       store_check_cachable_hist.no.negative_cached);
1032     storeAppendPrintf(sentry, "no.missing_parts\t%d\n",
1033                       store_check_cachable_hist.no.missing_parts);
1034     storeAppendPrintf(sentry, "no.too_big\t%d\n",
1035                       store_check_cachable_hist.no.too_big);
1036     storeAppendPrintf(sentry, "no.too_small\t%d\n",
1037                       store_check_cachable_hist.no.too_small);
1038     storeAppendPrintf(sentry, "no.private_key\t%d\n",
1039                       store_check_cachable_hist.no.private_key);
1040     storeAppendPrintf(sentry, "no.too_many_open_files\t%d\n",
1041                       store_check_cachable_hist.no.too_many_open_files);
1042     storeAppendPrintf(sentry, "no.too_many_open_fds\t%d\n",
1043                       store_check_cachable_hist.no.too_many_open_fds);
1044     storeAppendPrintf(sentry, "yes.default\t%d\n",
1045                       store_check_cachable_hist.yes.Default);
1046 }
1047
1048 void
1049 StoreEntry::complete()
1050 {
1051     debugs(20, 3, "storeComplete: '" << getMD5Text() << "'");
1052
1053     if (store_status != STORE_PENDING) {
1054         /*
1055          * if we're not STORE_PENDING, then probably we got aborted
1056          * and there should be NO clients on this entry
1057          */
1058         assert(EBIT_TEST(flags, ENTRY_ABORTED));
1059         assert(mem_obj->nclients == 0);
1060         return;
1061     }
1062
1063     /* This is suspect: mem obj offsets include the headers. do we adjust for that
1064      * in use of object_sz?
1065      */
1066     mem_obj->object_sz = mem_obj->endOffset();
1067
1068     store_status = STORE_OK;
1069
1070     assert(mem_status == NOT_IN_MEMORY);
1071
1072     if (!validLength()) {
1073         EBIT_SET(flags, ENTRY_BAD_LENGTH);
1074         releaseRequest();
1075     }
1076
1077 #if USE_CACHE_DIGESTS
1078     if (mem_obj->request)
1079         mem_obj->request->hier.store_complete_stop = current_time;
1080
1081 #endif
1082     /*
1083      * We used to call invokeHandlers, then storeSwapOut.  However,
1084      * Madhukar Reddy <myreddy@persistence.com> reported that
1085      * responses without content length would sometimes get released
1086      * in client_side, thinking that the response is incomplete.
1087      */
1088     invokeHandlers();
1089 }
1090
1091 /*
1092  * Someone wants to abort this transfer.  Set the reason in the
1093  * request structure, call the callback and mark the
1094  * entry for releasing
1095  */
1096 void
1097 StoreEntry::abort()
1098 {
1099     ++statCounter.aborted_requests;
1100     assert(store_status == STORE_PENDING);
1101     assert(mem_obj != NULL);
1102     debugs(20, 6, "storeAbort: " << getMD5Text());
1103
1104     lock("StoreEntry::abort");         /* lock while aborting */
1105     negativeCache();
1106
1107     releaseRequest();
1108
1109     EBIT_SET(flags, ENTRY_ABORTED);
1110
1111     setMemStatus(NOT_IN_MEMORY);
1112
1113     store_status = STORE_OK;
1114
1115     /* Notify the server side */
1116
1117     /*
1118      * DPW 2007-05-07
1119      * Should we check abort.data for validity?
1120      */
1121     if (mem_obj->abort.callback) {
1122         if (!cbdataReferenceValid(mem_obj->abort.data))
1123             debugs(20, DBG_IMPORTANT,HERE << "queueing event when abort.data is not valid");
1124         eventAdd("mem_obj->abort.callback",
1125                  mem_obj->abort.callback,
1126                  mem_obj->abort.data,
1127                  0.0,
1128                  true);
1129         unregisterAbort();
1130     }
1131
1132     /* XXX Should we reverse these two, so that there is no
1133      * unneeded disk swapping triggered?
1134      */
1135     /* Notify the client side */
1136     invokeHandlers();
1137
1138     // abort swap out, invalidating what was created so far (release follows)
1139     swapOutFileClose(StoreIOState::writerGone);
1140
1141     unlock("StoreEntry::abort");       /* unlock */
1142 }
1143
1144 /**
1145  * Clear Memory storage to accommodate the given object len
1146  */
1147 void
1148 storeGetMemSpace(int size)
1149 {
1150     PROF_start(storeGetMemSpace);
1151     StoreEntry *e = NULL;
1152     int released = 0;
1153     static time_t last_check = 0;
1154     size_t pages_needed;
1155     RemovalPurgeWalker *walker;
1156
1157     if (squid_curtime == last_check) {
1158         PROF_stop(storeGetMemSpace);
1159         return;
1160     }
1161
1162     last_check = squid_curtime;
1163
1164     pages_needed = (size + SM_PAGE_SIZE-1) / SM_PAGE_SIZE;
1165
1166     if (mem_node::InUseCount() + pages_needed < store_pages_max) {
1167         PROF_stop(storeGetMemSpace);
1168         return;
1169     }
1170
1171     debugs(20, 2, "storeGetMemSpace: Starting, need " << pages_needed <<
1172            " pages");
1173
1174     /* XXX what to set as max_scan here? */
1175     walker = mem_policy->PurgeInit(mem_policy, 100000);
1176
1177     while ((e = walker->Next(walker))) {
1178         e->purgeMem();
1179         ++released;
1180
1181         if (mem_node::InUseCount() + pages_needed < store_pages_max)
1182             break;
1183     }
1184
1185     walker->Done(walker);
1186     debugs(20, 3, "storeGetMemSpace stats:");
1187     debugs(20, 3, "  " << std::setw(6) << hot_obj_count  << " HOT objects");
1188     debugs(20, 3, "  " << std::setw(6) << released  << " were released");
1189     PROF_stop(storeGetMemSpace);
1190 }
1191
1192 /* thunk through to Store::Root().maintain(). Note that this would be better still
1193  * if registered against the root store itself, but that requires more complex
1194  * update logic - bigger fish to fry first. Long term each store when
1195  * it becomes active will self register
1196  */
1197 void
1198 Store::Maintain(void *notused)
1199 {
1200     Store::Root().maintain();
1201
1202     /* Reregister a maintain event .. */
1203     eventAdd("MaintainSwapSpace", Maintain, NULL, 1.0, 1);
1204
1205 }
1206
1207 /* The maximum objects to scan for maintain storage space */
1208 #define MAINTAIN_MAX_SCAN       1024
1209 #define MAINTAIN_MAX_REMOVE     64
1210
1211 /*
1212  * This routine is to be called by main loop in main.c.
1213  * It removes expired objects on only one bucket for each time called.
1214  *
1215  * This should get called 1/s from main().
1216  */
1217 void
1218 StoreController::maintain()
1219 {
1220     static time_t last_warn_time = 0;
1221
1222     PROF_start(storeMaintainSwapSpace);
1223     swapDir->maintain();
1224
1225     /* this should be emitted by the oversize dir, not globally */
1226
1227     if (Store::Root().currentSize() > Store::Root().maxSize()) {
1228         if (squid_curtime - last_warn_time > 10) {
1229             debugs(20, DBG_CRITICAL, "WARNING: Disk space over limit: "
1230                    << Store::Root().currentSize() / 1024.0 << " KB > "
1231                    << (Store::Root().maxSize() >> 10) << " KB");
1232             last_warn_time = squid_curtime;
1233         }
1234     }
1235
1236     PROF_stop(storeMaintainSwapSpace);
1237 }
1238
1239 /* release an object from a cache */
1240 void
1241 StoreEntry::release()
1242 {
1243     PROF_start(storeRelease);
1244     debugs(20, 3, "releasing " << *this << ' ' << getMD5Text());
1245     /* If, for any reason we can't discard this object because of an
1246      * outstanding request, mark it for pending release */
1247
1248     if (locked()) {
1249         expireNow();
1250         debugs(20, 3, "storeRelease: Only setting RELEASE_REQUEST bit");
1251         releaseRequest();
1252         PROF_stop(storeRelease);
1253         return;
1254     }
1255
1256     Store::Root().memoryUnlink(*this);
1257
1258     if (StoreController::store_dirs_rebuilding && swap_filen > -1) {
1259         setPrivateKey();
1260
1261         if (swap_filen > -1) {
1262             // lock the entry until rebuilding is done
1263             lock("storeLateRelease");
1264             setReleaseFlag();
1265             LateReleaseStack.push(this);
1266         } else {
1267             destroyStoreEntry(static_cast<hash_link *>(this));
1268             // "this" is no longer valid
1269         }
1270
1271         PROF_stop(storeRelease);
1272         return;
1273     }
1274
1275     storeLog(STORE_LOG_RELEASE, this);
1276
1277     if (swap_filen > -1) {
1278         // log before unlink() below clears swap_filen
1279         if (!EBIT_TEST(flags, KEY_PRIVATE))
1280             storeDirSwapLog(this, SWAP_LOG_DEL);
1281
1282         unlink();
1283     }
1284
1285     destroyStoreEntry(static_cast<hash_link *>(this));
1286     PROF_stop(storeRelease);
1287 }
1288
1289 static void
1290 storeLateRelease(void *unused)
1291 {
1292     StoreEntry *e;
1293     static int n = 0;
1294
1295     if (StoreController::store_dirs_rebuilding) {
1296         eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1297         return;
1298     }
1299
1300     // TODO: this works but looks unelegant.
1301     for (int i = 0; i < 10; ++i) {
1302         if (LateReleaseStack.empty()) {
1303             debugs(20, DBG_IMPORTANT, "storeLateRelease: released " << n << " objects");
1304             return;
1305         } else {
1306             e = LateReleaseStack.top();
1307             LateReleaseStack.pop();
1308         }
1309
1310         e->unlock("storeLateRelease");
1311         ++n;
1312     }
1313
1314     eventAdd("storeLateRelease", storeLateRelease, NULL, 0.0, 1);
1315 }
1316
1317 /* return 1 if a store entry is locked */
1318 int
1319 StoreEntry::locked() const
1320 {
1321     if (lock_count)
1322         return 1;
1323
1324     /*
1325      * SPECIAL, PUBLIC entries should be "locked";
1326      * XXX: Their owner should lock them then instead of relying on this hack.
1327      */
1328     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1329         if (!EBIT_TEST(flags, KEY_PRIVATE))
1330             return 1;
1331
1332     return 0;
1333 }
1334
1335 bool
1336 StoreEntry::validLength() const
1337 {
1338     int64_t diff;
1339     const HttpReply *reply;
1340     assert(mem_obj != NULL);
1341     reply = getReply();
1342     debugs(20, 3, "storeEntryValidLength: Checking '" << getMD5Text() << "'");
1343     debugs(20, 5, "storeEntryValidLength:     object_len = " <<
1344            objectLen());
1345     debugs(20, 5, "storeEntryValidLength:         hdr_sz = " << reply->hdr_sz);
1346     debugs(20, 5, "storeEntryValidLength: content_length = " << reply->content_length);
1347
1348     if (reply->content_length < 0) {
1349         debugs(20, 5, "storeEntryValidLength: Unspecified content length: " << getMD5Text());
1350         return 1;
1351     }
1352
1353     if (reply->hdr_sz == 0) {
1354         debugs(20, 5, "storeEntryValidLength: Zero header size: " << getMD5Text());
1355         return 1;
1356     }
1357
1358     if (mem_obj->method == Http::METHOD_HEAD) {
1359         debugs(20, 5, "storeEntryValidLength: HEAD request: " << getMD5Text());
1360         return 1;
1361     }
1362
1363     if (reply->sline.status() == Http::scNotModified)
1364         return 1;
1365
1366     if (reply->sline.status() == Http::scNoContent)
1367         return 1;
1368
1369     diff = reply->hdr_sz + reply->content_length - objectLen();
1370
1371     if (diff == 0)
1372         return 1;
1373
1374     debugs(20, 3, "storeEntryValidLength: " << (diff < 0 ? -diff : diff)  << " bytes too " << (diff < 0 ? "big" : "small") <<"; '" << getMD5Text() << "'" );
1375
1376     return 0;
1377 }
1378
1379 static void
1380 storeRegisterWithCacheManager(void)
1381 {
1382     Mgr::RegisterAction("storedir", "Store Directory Stats", Store::Stats, 0, 1);
1383     Mgr::RegisterAction("store_io", "Store IO Interface Stats", &Mgr::StoreIoAction::Create, 0, 1);
1384     Mgr::RegisterAction("store_check_cachable_stats", "storeCheckCachable() Stats",
1385                         storeCheckCachableStats, 0, 1);
1386 }
1387
1388 void
1389 storeInit(void)
1390 {
1391     storeKeyInit();
1392     mem_policy = createRemovalPolicy(Config.memPolicy);
1393     storeDigestInit();
1394     storeLogOpen();
1395     eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1396     Store::Root().init();
1397     storeRebuildStart();
1398
1399     storeRegisterWithCacheManager();
1400 }
1401
1402 /// computes maximum size of a cachable object
1403 /// larger objects are rejected by all (disk and memory) cache stores
1404 static int64_t
1405 storeCalcMaxObjSize()
1406 {
1407     int64_t ms = 0; // nothing can be cached without at least one store consent
1408
1409     // global maximum is at least the disk store maximum
1410     for (int i = 0; i < Config.cacheSwap.n_configured; ++i) {
1411         assert (Config.cacheSwap.swapDirs[i].getRaw());
1412         const int64_t storeMax = dynamic_cast<SwapDir *>(Config.cacheSwap.swapDirs[i].getRaw())->maxObjectSize();
1413         if (ms < storeMax)
1414             ms = storeMax;
1415     }
1416
1417     // global maximum is at least the memory store maximum
1418     // TODO: move this into a memory cache class when we have one
1419     const int64_t memMax = static_cast<int64_t>(min(Config.Store.maxInMemObjSize, Config.memMaxSize));
1420     if (ms < memMax)
1421         ms = memMax;
1422
1423     return ms;
1424 }
1425
1426 void
1427 storeConfigure(void)
1428 {
1429     store_swap_high = (long) (((float) Store::Root().maxSize() *
1430                                (float) Config.Swap.highWaterMark) / (float) 100);
1431     store_swap_low = (long) (((float) Store::Root().maxSize() *
1432                               (float) Config.Swap.lowWaterMark) / (float) 100);
1433     store_pages_max = Config.memMaxSize / sizeof(mem_node);
1434
1435     store_maxobjsize = storeCalcMaxObjSize();
1436 }
1437
1438 bool
1439 StoreEntry::memoryCachable()
1440 {
1441     if (!checkCachable())
1442         return 0;
1443
1444     if (mem_obj == NULL)
1445         return 0;
1446
1447     if (mem_obj->data_hdr.size() == 0)
1448         return 0;
1449
1450     if (mem_obj->inmem_lo != 0)
1451         return 0;
1452
1453     if (!Config.onoff.memory_cache_first && swap_status == SWAPOUT_DONE && refcount == 1)
1454         return 0;
1455
1456     return 1;
1457 }
1458
1459 int
1460 StoreEntry::checkNegativeHit() const
1461 {
1462     if (!EBIT_TEST(flags, ENTRY_NEGCACHED))
1463         return 0;
1464
1465     if (expires <= squid_curtime)
1466         return 0;
1467
1468     if (store_status != STORE_OK)
1469         return 0;
1470
1471     return 1;
1472 }
1473
1474 /**
1475  * Set object for negative caching.
1476  * Preserves any expiry information given by the server.
1477  * In absence of proper expiry info it will set to expire immediately,
1478  * or with HTTP-violations enabled the configured negative-TTL is observed
1479  */
1480 void
1481 StoreEntry::negativeCache()
1482 {
1483     // XXX: should make the default for expires 0 instead of -1
1484     //      so we can distinguish "Expires: -1" from nothing.
1485     if (expires <= 0)
1486 #if USE_HTTP_VIOLATIONS
1487         expires = squid_curtime + Config.negativeTtl;
1488 #else
1489         expires = squid_curtime;
1490 #endif
1491     EBIT_SET(flags, ENTRY_NEGCACHED);
1492 }
1493
1494 void
1495 storeFreeMemory(void)
1496 {
1497     Store::Root(NULL);
1498 #if USE_CACHE_DIGESTS
1499
1500     if (store_digest)
1501         cacheDigestDestroy(store_digest);
1502
1503 #endif
1504
1505     store_digest = NULL;
1506 }
1507
1508 int
1509 expiresMoreThan(time_t expires, time_t when)
1510 {
1511     if (expires < 0)            /* No Expires given */
1512         return 1;
1513
1514     return (expires > (squid_curtime + when));
1515 }
1516
1517 int
1518 StoreEntry::validToSend() const
1519 {
1520     if (EBIT_TEST(flags, RELEASE_REQUEST))
1521         return 0;
1522
1523     if (EBIT_TEST(flags, ENTRY_NEGCACHED))
1524         if (expires <= squid_curtime)
1525             return 0;
1526
1527     if (EBIT_TEST(flags, ENTRY_ABORTED))
1528         return 0;
1529
1530     // now check that the entry has a cache backing or is collapsed
1531     if (swap_filen > -1) // backed by a disk cache
1532         return 1;
1533
1534     if (swappingOut()) // will be backed by a disk cache
1535         return 1;
1536
1537     if (!mem_obj) // not backed by a memory cache and not collapsed
1538         return 0;
1539
1540     // StoreEntry::storeClientType() assumes DISK_CLIENT here, but there is no
1541     // disk cache backing that store_client constructor will assert. XXX: This
1542     // is wrong for range requests (that could feed off nibbled memory) and for
1543     // entries backed by the shared memory cache (that could, in theory, get
1544     // nibbled bytes from that cache, but there is no such "memoryIn" code).
1545     if (mem_obj->inmem_lo) // in memory cache, but got nibbled at
1546         return 0;
1547
1548     // The following check is correct but useless at this position. TODO: Move
1549     // it up when the shared memory cache can either replenish locally nibbled
1550     // bytes or, better, does not use local RAM copy at all.
1551     // if (mem_obj->memCache.index >= 0) // backed by a shared memory cache
1552     //    return 1;
1553
1554     return 1;
1555 }
1556
1557 void
1558 StoreEntry::timestampsSet()
1559 {
1560     const HttpReply *reply = getReply();
1561     time_t served_date = reply->date;
1562     int age = reply->header.getInt(HDR_AGE);
1563     /* Compute the timestamp, mimicking RFC2616 section 13.2.3. */
1564     /* make sure that 0 <= served_date <= squid_curtime */
1565
1566     if (served_date < 0 || served_date > squid_curtime)
1567         served_date = squid_curtime;
1568
1569     /* Bug 1791:
1570      * If the returned Date: is more than 24 hours older than
1571      * the squid_curtime, then one of us needs to use NTP to set our
1572      * clock.  We'll pretend that our clock is right.
1573      */
1574     else if (served_date < (squid_curtime - 24 * 60 * 60) )
1575         served_date = squid_curtime;
1576
1577     /*
1578      * Compensate with Age header if origin server clock is ahead
1579      * of us and there is a cache in between us and the origin
1580      * server.  But DONT compensate if the age value is larger than
1581      * squid_curtime because it results in a negative served_date.
1582      */
1583     if (age > squid_curtime - served_date)
1584         if (squid_curtime > age)
1585             served_date = squid_curtime - age;
1586
1587     // compensate for Squid-to-server and server-to-Squid delays
1588     if (mem_obj && mem_obj->request) {
1589         const time_t request_sent =
1590             mem_obj->request->hier.peer_http_request_sent.tv_sec;
1591         if (0 < request_sent && request_sent < squid_curtime)
1592             served_date -= (squid_curtime - request_sent);
1593     }
1594
1595     if (reply->expires > 0 && reply->date > -1)
1596         expires = served_date + (reply->expires - reply->date);
1597     else
1598         expires = reply->expires;
1599
1600     lastmod = reply->last_modified;
1601
1602     timestamp = served_date;
1603 }
1604
1605 void
1606 StoreEntry::registerAbort(STABH * cb, void *data)
1607 {
1608     assert(mem_obj);
1609     assert(mem_obj->abort.callback == NULL);
1610     mem_obj->abort.callback = cb;
1611     mem_obj->abort.data = cbdataReference(data);
1612 }
1613
1614 void
1615 StoreEntry::unregisterAbort()
1616 {
1617     assert(mem_obj);
1618     if (mem_obj->abort.callback) {
1619         mem_obj->abort.callback = NULL;
1620         cbdataReferenceDone(mem_obj->abort.data);
1621     }
1622 }
1623
1624 void
1625 StoreEntry::dump(int l) const
1626 {
1627     debugs(20, l, "StoreEntry->key: " << getMD5Text());
1628     debugs(20, l, "StoreEntry->next: " << next);
1629     debugs(20, l, "StoreEntry->mem_obj: " << mem_obj);
1630     debugs(20, l, "StoreEntry->timestamp: " << timestamp);
1631     debugs(20, l, "StoreEntry->lastref: " << lastref);
1632     debugs(20, l, "StoreEntry->expires: " << expires);
1633     debugs(20, l, "StoreEntry->lastmod: " << lastmod);
1634     debugs(20, l, "StoreEntry->swap_file_sz: " << swap_file_sz);
1635     debugs(20, l, "StoreEntry->refcount: " << refcount);
1636     debugs(20, l, "StoreEntry->flags: " << storeEntryFlags(this));
1637     debugs(20, l, "StoreEntry->swap_dirn: " << swap_dirn);
1638     debugs(20, l, "StoreEntry->swap_filen: " << swap_filen);
1639     debugs(20, l, "StoreEntry->lock_count: " << lock_count);
1640     debugs(20, l, "StoreEntry->mem_status: " << mem_status);
1641     debugs(20, l, "StoreEntry->ping_status: " << ping_status);
1642     debugs(20, l, "StoreEntry->store_status: " << store_status);
1643     debugs(20, l, "StoreEntry->swap_status: " << swap_status);
1644 }
1645
1646 /*
1647  * NOTE, this function assumes only two mem states
1648  */
1649 void
1650 StoreEntry::setMemStatus(mem_status_t new_status)
1651 {
1652     if (new_status == mem_status)
1653         return;
1654
1655     // are we using a shared memory cache?
1656     if (Config.memShared && IamWorkerProcess()) {
1657         // This method was designed to update replacement policy, not to
1658         // actually purge something from the memory cache (TODO: rename?).
1659         // Shared memory cache does not have a policy that needs updates.
1660         mem_status = new_status;
1661         return;
1662     }
1663
1664     assert(mem_obj != NULL);
1665
1666     if (new_status == IN_MEMORY) {
1667         assert(mem_obj->inmem_lo == 0);
1668
1669         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1670             debugs(20, 4, "not inserting special " << *this << " into policy");
1671         } else {
1672             mem_policy->Add(mem_policy, this, &mem_obj->repl);
1673             debugs(20, 4, "inserted " << *this << " key: " << getMD5Text());
1674         }
1675
1676         ++hot_obj_count; // TODO: maintain for the shared hot cache as well
1677     } else {
1678         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1679             debugs(20, 4, "not removing special " << *this << " from policy");
1680         } else {
1681             mem_policy->Remove(mem_policy, this, &mem_obj->repl);
1682             debugs(20, 4, "removed " << *this);
1683         }
1684
1685         --hot_obj_count;
1686     }
1687
1688     mem_status = new_status;
1689 }
1690
1691 const char *
1692 StoreEntry::url() const
1693 {
1694     if (mem_obj == NULL)
1695         return "[null_mem_obj]";
1696     else
1697         return mem_obj->storeId();
1698 }
1699
1700 MemObject *
1701 StoreEntry::makeMemObject()
1702 {
1703     if (!mem_obj)
1704         mem_obj = new MemObject();
1705     return mem_obj;
1706 }
1707
1708 void
1709 StoreEntry::createMemObject(const char *aUrl, const char *aLogUrl, const HttpRequestMethod &aMethod)
1710 {
1711     makeMemObject();
1712     mem_obj->setUris(aUrl, aLogUrl, aMethod);
1713 }
1714
1715 /* this just sets DELAY_SENDING */
1716 void
1717 StoreEntry::buffer()
1718 {
1719     EBIT_SET(flags, DELAY_SENDING);
1720 }
1721
1722 /* this just clears DELAY_SENDING and Invokes the handlers */
1723 void
1724 StoreEntry::flush()
1725 {
1726     if (EBIT_TEST(flags, DELAY_SENDING)) {
1727         EBIT_CLR(flags, DELAY_SENDING);
1728         invokeHandlers();
1729     }
1730 }
1731
1732 int64_t
1733 StoreEntry::objectLen() const
1734 {
1735     assert(mem_obj != NULL);
1736     return mem_obj->object_sz;
1737 }
1738
1739 int64_t
1740 StoreEntry::contentLen() const
1741 {
1742     assert(mem_obj != NULL);
1743     assert(getReply() != NULL);
1744     return objectLen() - getReply()->hdr_sz;
1745 }
1746
1747 HttpReply const *
1748 StoreEntry::getReply () const
1749 {
1750     if (NULL == mem_obj)
1751         return NULL;
1752
1753     return mem_obj->getReply();
1754 }
1755
1756 void
1757 StoreEntry::reset()
1758 {
1759     assert (mem_obj);
1760     debugs(20, 3, "StoreEntry::reset: " << url());
1761     mem_obj->reset();
1762     HttpReply *rep = (HttpReply *) getReply();       // bypass const
1763     rep->reset();
1764     expires = lastmod = timestamp = -1;
1765 }
1766
1767 /*
1768  * storeFsInit
1769  *
1770  * This routine calls the SETUP routine for each fs type.
1771  * I don't know where the best place for this is, and I'm not going to shuffle
1772  * around large chunks of code right now (that can be done once its working.)
1773  */
1774 void
1775 storeFsInit(void)
1776 {
1777     storeReplSetup();
1778 }
1779
1780 /*
1781  * called to add another store removal policy module
1782  */
1783 void
1784 storeReplAdd(const char *type, REMOVALPOLICYCREATE * create)
1785 {
1786     int i;
1787
1788     /* find the number of currently known repl types */
1789     for (i = 0; storerepl_list && storerepl_list[i].typestr; ++i) {
1790         if (strcmp(storerepl_list[i].typestr, type) == 0) {
1791             debugs(20, DBG_IMPORTANT, "WARNING: Trying to load store replacement policy " << type << " twice.");
1792             return;
1793         }
1794     }
1795
1796     /* add the new type */
1797     storerepl_list = static_cast<storerepl_entry_t *>(xrealloc(storerepl_list, (i + 2) * sizeof(storerepl_entry_t)));
1798
1799     memset(&storerepl_list[i + 1], 0, sizeof(storerepl_entry_t));
1800
1801     storerepl_list[i].typestr = type;
1802
1803     storerepl_list[i].create = create;
1804 }
1805
1806 /*
1807  * Create a removal policy instance
1808  */
1809 RemovalPolicy *
1810 createRemovalPolicy(RemovalPolicySettings * settings)
1811 {
1812     storerepl_entry_t *r;
1813
1814     for (r = storerepl_list; r && r->typestr; ++r) {
1815         if (strcmp(r->typestr, settings->type) == 0)
1816             return r->create(settings->args);
1817     }
1818
1819     debugs(20, DBG_IMPORTANT, "ERROR: Unknown policy " << settings->type);
1820     debugs(20, DBG_IMPORTANT, "ERROR: Be sure to have set cache_replacement_policy");
1821     debugs(20, DBG_IMPORTANT, "ERROR:   and memory_replacement_policy in squid.conf!");
1822     fatalf("ERROR: Unknown policy %s\n", settings->type);
1823     return NULL;                /* NOTREACHED */
1824 }
1825
1826 #if 0
1827 void
1828 storeSwapFileNumberSet(StoreEntry * e, sfileno filn)
1829 {
1830     if (e->swap_file_number == filn)
1831         return;
1832
1833     if (filn < 0) {
1834         assert(-1 == filn);
1835         storeDirMapBitReset(e->swap_file_number);
1836         storeDirLRUDelete(e);
1837         e->swap_file_number = -1;
1838     } else {
1839         assert(-1 == e->swap_file_number);
1840         storeDirMapBitSet(e->swap_file_number = filn);
1841         storeDirLRUAdd(e);
1842     }
1843 }
1844
1845 #endif
1846
1847 void
1848 StoreEntry::storeErrorResponse(HttpReply *reply)
1849 {
1850     lock("StoreEntry::storeErrorResponse");
1851     buffer();
1852     replaceHttpReply(reply);
1853     flush();
1854     complete();
1855     negativeCache();
1856     releaseRequest();
1857     unlock("StoreEntry::storeErrorResponse");
1858 }
1859
1860 /*
1861  * Replace a store entry with
1862  * a new reply. This eats the reply.
1863  */
1864 void
1865 StoreEntry::replaceHttpReply(HttpReply *rep, bool andStartWriting)
1866 {
1867     debugs(20, 3, "StoreEntry::replaceHttpReply: " << url());
1868
1869     if (!mem_obj) {
1870         debugs(20, DBG_CRITICAL, "Attempt to replace object with no in-memory representation");
1871         return;
1872     }
1873
1874     mem_obj->replaceHttpReply(rep);
1875
1876     if (andStartWriting)
1877         startWriting();
1878 }
1879
1880 void
1881 StoreEntry::startWriting()
1882 {
1883     Packer p;
1884
1885     /* TODO: when we store headers serparately remove the header portion */
1886     /* TODO: mark the length of the headers ? */
1887     /* We ONLY want the headers */
1888     packerToStoreInit(&p, this);
1889
1890     assert (isEmpty());
1891     assert(mem_obj);
1892
1893     const HttpReply *rep = getReply();
1894     assert(rep);
1895
1896     rep->packHeadersInto(&p);
1897     mem_obj->markEndOfReplyHeaders();
1898     EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
1899
1900     rep->body.packInto(&p);
1901
1902     packerClean(&p);
1903 }
1904
1905 char const *
1906 StoreEntry::getSerialisedMetaData()
1907 {
1908     StoreMeta *tlv_list = storeSwapMetaBuild(this);
1909     int swap_hdr_sz;
1910     char *result = storeSwapMetaPack(tlv_list, &swap_hdr_sz);
1911     storeSwapTLVFree(tlv_list);
1912     assert (swap_hdr_sz >= 0);
1913     mem_obj->swap_hdr_sz = (size_t) swap_hdr_sz;
1914     return result;
1915 }
1916
1917 /**
1918  * Abandon the transient entry our worker has created if neither the shared
1919  * memory cache nor the disk cache wants to store it. Collapsed requests, if
1920  * any, should notice and use Plan B instead of getting stuck waiting for us
1921  * to start swapping the entry out.
1922  */
1923 void
1924 StoreEntry::transientsAbandonmentCheck()
1925 {
1926     if (mem_obj && !mem_obj->smpCollapsed && // this worker is responsible
1927             mem_obj->xitTable.index >= 0 && // other workers may be interested
1928             mem_obj->memCache.index < 0 && // rejected by the shared memory cache
1929             mem_obj->swapout.decision == MemObject::SwapOut::swImpossible) {
1930         debugs(20, 7, "cannot be shared: " << *this);
1931         if (!shutting_down) // Store::Root() is FATALly missing during shutdown
1932             Store::Root().transientsAbandon(*this);
1933     }
1934 }
1935
1936 void
1937 StoreEntry::memOutDecision(const bool willCacheInRam)
1938 {
1939     transientsAbandonmentCheck();
1940 }
1941
1942 void
1943 StoreEntry::swapOutDecision(const MemObject::SwapOut::Decision &decision)
1944 {
1945     // Abandon our transient entry if neither shared memory nor disk wants it.
1946     assert(mem_obj);
1947     mem_obj->swapout.decision = decision;
1948     transientsAbandonmentCheck();
1949 }
1950
1951 void
1952 StoreEntry::trimMemory(const bool preserveSwappable)
1953 {
1954     /*
1955      * DPW 2007-05-09
1956      * Bug #1943.  We must not let go any data for IN_MEMORY
1957      * objects.  We have to wait until the mem_status changes.
1958      */
1959     if (mem_status == IN_MEMORY)
1960         return;
1961
1962     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1963         return; // cannot trim because we do not load them again
1964
1965     if (preserveSwappable)
1966         mem_obj->trimSwappable();
1967     else
1968         mem_obj->trimUnSwappable();
1969
1970     debugs(88, 7, *this << " inmem_lo=" << mem_obj->inmem_lo);
1971 }
1972
1973 bool
1974 StoreEntry::modifiedSince(HttpRequest * request) const
1975 {
1976     int object_length;
1977     time_t mod_time = lastmod;
1978
1979     if (mod_time < 0)
1980         mod_time = timestamp;
1981
1982     debugs(88, 3, "modifiedSince: '" << url() << "'");
1983
1984     debugs(88, 3, "modifiedSince: mod_time = " << mod_time);
1985
1986     if (mod_time < 0)
1987         return true;
1988
1989     /* Find size of the object */
1990     object_length = getReply()->content_length;
1991
1992     if (object_length < 0)
1993         object_length = contentLen();
1994
1995     if (mod_time > request->ims) {
1996         debugs(88, 3, "--> YES: entry newer than client");
1997         return true;
1998     } else if (mod_time < request->ims) {
1999         debugs(88, 3, "-->  NO: entry older than client");
2000         return false;
2001     } else if (request->imslen < 0) {
2002         debugs(88, 3, "-->  NO: same LMT, no client length");
2003         return false;
2004     } else if (request->imslen == object_length) {
2005         debugs(88, 3, "-->  NO: same LMT, same length");
2006         return false;
2007     } else {
2008         debugs(88, 3, "--> YES: same LMT, different length");
2009         return true;
2010     }
2011 }
2012
2013 bool
2014 StoreEntry::hasEtag(ETag &etag) const
2015 {
2016     if (const HttpReply *reply = getReply()) {
2017         etag = reply->header.getETag(HDR_ETAG);
2018         if (etag.str)
2019             return true;
2020     }
2021     return false;
2022 }
2023
2024 bool
2025 StoreEntry::hasIfMatchEtag(const HttpRequest &request) const
2026 {
2027     const String reqETags = request.header.getList(HDR_IF_MATCH);
2028     return hasOneOfEtags(reqETags, false);
2029 }
2030
2031 bool
2032 StoreEntry::hasIfNoneMatchEtag(const HttpRequest &request) const
2033 {
2034     const String reqETags = request.header.getList(HDR_IF_NONE_MATCH);
2035     // weak comparison is allowed only for HEAD or full-body GET requests
2036     const bool allowWeakMatch = !request.flags.isRanged &&
2037                                 (request.method == Http::METHOD_GET || request.method == Http::METHOD_HEAD);
2038     return hasOneOfEtags(reqETags, allowWeakMatch);
2039 }
2040
2041 /// whether at least one of the request ETags matches entity ETag
2042 bool
2043 StoreEntry::hasOneOfEtags(const String &reqETags, const bool allowWeakMatch) const
2044 {
2045     const ETag repETag = getReply()->header.getETag(HDR_ETAG);
2046     if (!repETag.str)
2047         return strListIsMember(&reqETags, "*", ',');
2048
2049     bool matched = false;
2050     const char *pos = NULL;
2051     const char *item;
2052     int ilen;
2053     while (!matched && strListGetItem(&reqETags, ',', &item, &ilen, &pos)) {
2054         if (!strncmp(item, "*", ilen))
2055             matched = true;
2056         else {
2057             String str;
2058             str.append(item, ilen);
2059             ETag reqETag;
2060             if (etagParseInit(&reqETag, str.termedBuf())) {
2061                 matched = allowWeakMatch ? etagIsWeakEqual(repETag, reqETag) :
2062                           etagIsStrongEqual(repETag, reqETag);
2063             }
2064         }
2065     }
2066     return matched;
2067 }
2068
2069 SwapDir::Pointer
2070 StoreEntry::store() const
2071 {
2072     assert(0 <= swap_dirn && swap_dirn < Config.cacheSwap.n_configured);
2073     return INDEXSD(swap_dirn);
2074 }
2075
2076 void
2077 StoreEntry::unlink()
2078 {
2079     store()->unlink(*this); // implies disconnect()
2080     swap_filen = -1;
2081     swap_dirn = -1;
2082     swap_status = SWAPOUT_NONE;
2083 }
2084
2085 /*
2086  * return true if the entry is in a state where
2087  * it can accept more data (ie with write() method)
2088  */
2089 bool
2090 StoreEntry::isAccepting() const
2091 {
2092     if (STORE_PENDING != store_status)
2093         return false;
2094
2095     if (EBIT_TEST(flags, ENTRY_ABORTED))
2096         return false;
2097
2098     return true;
2099 }
2100
2101 std::ostream &operator <<(std::ostream &os, const StoreEntry &e)
2102 {
2103     os << "e:";
2104
2105     if (e.mem_obj) {
2106         if (e.mem_obj->xitTable.index > -1)
2107             os << 't' << e.mem_obj->xitTable.index;
2108         if (e.mem_obj->memCache.index > -1)
2109             os << 'm' << e.mem_obj->memCache.index;
2110     }
2111     if (e.swap_filen > -1 || e.swap_dirn > -1)
2112         os << 'd' << e.swap_filen << '@' << e.swap_dirn;
2113
2114     os << '=';
2115
2116     // print only non-default status values, using unique letters
2117     if (e.mem_status != NOT_IN_MEMORY ||
2118             e.store_status != STORE_PENDING ||
2119             e.swap_status != SWAPOUT_NONE ||
2120             e.ping_status != PING_NONE) {
2121         if (e.mem_status != NOT_IN_MEMORY) os << 'm';
2122         if (e.store_status != STORE_PENDING) os << 's';
2123         if (e.swap_status != SWAPOUT_NONE) os << 'w' << e.swap_status;
2124         if (e.ping_status != PING_NONE) os << 'p' << e.ping_status;
2125     }
2126
2127     // print only set flags, using unique letters
2128     if (e.flags) {
2129         if (EBIT_TEST(e.flags, ENTRY_SPECIAL)) os << 'S';
2130         if (EBIT_TEST(e.flags, ENTRY_REVALIDATE)) os << 'R';
2131         if (EBIT_TEST(e.flags, DELAY_SENDING)) os << 'P';
2132         if (EBIT_TEST(e.flags, RELEASE_REQUEST)) os << 'X';
2133         if (EBIT_TEST(e.flags, REFRESH_REQUEST)) os << 'F';
2134         if (EBIT_TEST(e.flags, ENTRY_DISPATCHED)) os << 'D';
2135         if (EBIT_TEST(e.flags, KEY_PRIVATE)) os << 'I';
2136         if (EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT)) os << 'W';
2137         if (EBIT_TEST(e.flags, ENTRY_NEGCACHED)) os << 'N';
2138         if (EBIT_TEST(e.flags, ENTRY_VALIDATED)) os << 'V';
2139         if (EBIT_TEST(e.flags, ENTRY_BAD_LENGTH)) os << 'L';
2140         if (EBIT_TEST(e.flags, ENTRY_ABORTED)) os << 'A';
2141     }
2142
2143     if (e.mem_obj && e.mem_obj->smpCollapsed)
2144         os << 'O';
2145
2146     return os << '/' << &e << '*' << e.locks();
2147 }
2148
2149 /* NullStoreEntry */
2150
2151 NullStoreEntry NullStoreEntry::_instance;
2152
2153 NullStoreEntry *
2154 NullStoreEntry::getInstance()
2155 {
2156     return &_instance;
2157 }
2158
2159 char const *
2160 NullStoreEntry::getMD5Text() const
2161 {
2162     return "N/A";
2163 }
2164
2165 void
2166 NullStoreEntry::operator delete(void*)
2167 {
2168     fatal ("Attempt to delete NullStoreEntry\n");
2169 }
2170
2171 char const *
2172 NullStoreEntry::getSerialisedMetaData()
2173 {
2174     return NULL;
2175 }
2176