src/store.cc

   1
   2 /*
   3  * DEBUG: section 20    Storage Manager
   4  * AUTHOR: Harvest Derived
   5  *
   6  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   7  * ----------------------------------------------------------
   8  *
   9  *  Squid is the result of efforts by numerous individuals from
  10  *  the Internet community; see the CONTRIBUTORS file for full
  11  *  details.   Many organizations have provided support for Squid's
  12  *  development; see the SPONSORS file for full details.  Squid is
  13  *  Copyrighted (C) 2001 by the Regents of the University of
  14  *  California; see the COPYRIGHT file for full details.  Squid
  15  *  incorporates software developed and/or copyrighted by other
  16  *  sources; see the CREDITS file for full details.
  17  *
  18  *  This program is free software; you can redistribute it and/or modify
  19  *  it under the terms of the GNU General Public License as published by
  20  *  the Free Software Foundation; either version 2 of the License, or
  21  *  (at your option) any later version.
  22  *
  23  *  This program is distributed in the hope that it will be useful,
  24  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *  GNU General Public License for more details.
  27  *
  28  *  You should have received a copy of the GNU General Public License
  29  *  along with this program; if not, write to the Free Software
  30  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  31  *
  32  */
  33
  34 #include "squid.h"
  35 #include "CacheDigest.h"
  36 #include "CacheManager.h"
  37 #include "comm/Connection.h"
  38 #include "ETag.h"
  39 #include "event.h"
  40 #include "fde.h"
  41 #include "globals.h"
  42 #include "http.h"
  43 #include "HttpReply.h"
  44 #include "HttpRequest.h"
  45 #include "mem_node.h"
  46 #include "MemObject.h"
  47 #include "mgr/Registration.h"
  48 #include "mgr/StoreIoAction.h"
  49 #include "profiler/Profiler.h"
  50 #include "repl_modules.h"
  51 #include "RequestFlags.h"
  52 #include "SquidConfig.h"
  53 #include "SquidTime.h"
  54 #include "Stack.h"
  55 #include "StatCounters.h"
  56 #include "stmem.h"
  57 #include "Store.h"
  58 #include "store_digest.h"
  59 #include "store_key_md5.h"
  60 #include "store_key_md5.h"
  61 #include "store_log.h"
  62 #include "store_rebuild.h"
  63 #include "StoreClient.h"
  64 #include "StoreIOState.h"
  65 #include "StoreMeta.h"
  66 #include "StrList.h"
  67 #include "swap_log_op.h"
  68 #include "SwapDir.h"
  69 #include "tools.h"
  70 #if USE_DELAY_POOLS
  71 #include "DelayPools.h"
  72 #endif
  73 #if HAVE_LIMITS_H
  74 #include <limits.h>
  75 #endif
  76
  77 #define REBUILD_TIMESTAMP_DELTA_MAX 2
  78
  79 #define STORE_IN_MEM_BUCKETS            (229)
  80
  81 /** \todo Convert these string constants to enum string-arrays generated */
  82
  83 const char *memStatusStr[] = {
  84     "NOT_IN_MEMORY",
  85     "IN_MEMORY"
  86 };
  87
  88 const char *pingStatusStr[] = {
  89     "PING_NONE",
  90     "PING_WAITING",
  91     "PING_DONE"
  92 };
  93
  94 const char *storeStatusStr[] = {
  95     "STORE_OK",
  96     "STORE_PENDING"
  97 };
  98
  99 const char *swapStatusStr[] = {
 100     "SWAPOUT_NONE",
 101     "SWAPOUT_WRITING",
 102     "SWAPOUT_DONE"
 103 };
 104
 105 /*
 106  * This defines an repl type
 107  */
 108
 109 typedef struct _storerepl_entry storerepl_entry_t;
 110
 111 struct _storerepl_entry {
 112     const char *typestr;
 113     REMOVALPOLICYCREATE *create;
 114 };
 115
 116 static storerepl_entry_t *storerepl_list = NULL;
 117
 118 /*
 119  * local function prototypes
 120  */
 121 static int getKeyCounter(void);
 122 static OBJH storeCheckCachableStats;
 123 static EVH storeLateRelease;
 124
 125 /*
 126  * local variables
 127  */
 128 static Stack<StoreEntry*> LateReleaseStack;
 129 MemAllocator *StoreEntry::pool = NULL;
 130
 131 StorePointer Store::CurrentRoot = NULL;
 132
 133 void
 134 Store::Root(Store * aRoot)
 135 {
 136     CurrentRoot = aRoot;
 137 }
 138
 139 void
 140 Store::Root(StorePointer aRoot)
 141 {
 142     Root(aRoot.getRaw());
 143 }
 144
 145 void
 146 Store::Stats(StoreEntry * output)
 147 {
 148     assert (output);
 149     Root().stat(*output);
 150 }
 151
 152 void
 153 Store::create()
 154 {}
 155
 156 void
 157 Store::diskFull()
 158 {}
 159
 160 void
 161 Store::sync()
 162 {}
 163
 164 void
 165 Store::unlink (StoreEntry &anEntry)
 166 {
 167     fatal("Store::unlink on invalid Store\n");
 168 }
 169
 170 void *
 171 StoreEntry::operator new (size_t bytecount)
 172 {
 173     assert (bytecount == sizeof (StoreEntry));
 174
 175     if (!pool) {
 176         pool = memPoolCreate ("StoreEntry", bytecount);
 177         pool->setChunkSize(2048 * 1024);
 178     }
 179
 180     return pool->alloc();
 181 }
 182
 183 void
 184 StoreEntry::operator delete (void *address)
 185 {
 186     pool->freeOne(address);
 187 }
 188
 189 void
 190 StoreEntry::makePublic()
 191 {
 192     /* This object can be cached for a long time */
 193
 194     if (!EBIT_TEST(flags, RELEASE_REQUEST))
 195         setPublicKey();
 196 }
 197
 198 void
 199 StoreEntry::makePrivate()
 200 {
 201     /* This object should never be cached at all */
 202     expireNow();
 203     releaseRequest(); /* delete object when not used */
 204 }
 205
 206 void
 207 StoreEntry::cacheNegatively()
 208 {
 209     /* This object may be negatively cached */
 210     negativeCache();
 211     makePublic();
 212 }
 213
 214 size_t
 215 StoreEntry::inUseCount()
 216 {
 217     if (!pool)
 218         return 0;
 219     return pool->getInUseCount();
 220 }
 221
 222 const char *
 223 StoreEntry::getMD5Text() const
 224 {
 225     return storeKeyText((const cache_key *)key);
 226 }
 227
 228 #include "comm.h"
 229
 230 void
 231 StoreEntry::DeferReader(void *theContext, CommRead const &aRead)
 232 {
 233     StoreEntry *anEntry = (StoreEntry *)theContext;
 234     anEntry->delayAwareRead(aRead.conn,
 235                             aRead.buf,
 236                             aRead.len,
 237                             aRead.callback);
 238 }
 239
 240 void
 241 StoreEntry::delayAwareRead(const Comm::ConnectionPointer &conn, char *buf, int len, AsyncCall::Pointer callback)
 242 {
 243     size_t amountToRead = bytesWanted(Range<size_t>(0, len));
 244     /* sketch: readdeferer* = getdeferer.
 245      * ->deferRead (fd, buf, len, callback, DelayAwareRead, this)
 246      */
 247
 248     if (amountToRead == 0) {
 249         assert (mem_obj);
 250         /* read ahead limit */
 251         /* Perhaps these two calls should both live in MemObject */
 252 #if USE_DELAY_POOLS
 253         if (!mem_obj->readAheadPolicyCanRead()) {
 254 #endif
 255             mem_obj->delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 256             return;
 257 #if USE_DELAY_POOLS
 258         }
 259
 260         /* delay id limit */
 261         mem_obj->mostBytesAllowed().delayRead(DeferredRead(DeferReader, this, CommRead(conn, buf, len, callback)));
 262         return;
 263
 264 #endif
 265
 266     }
 267
 268     if (fd_table[conn->fd].closing()) {
 269         // Readers must have closing callbacks if they want to be notified. No
 270         // readers appeared to care around 2009/12/14 as they skipped reading
 271         // for other reasons. Closing may already be true at the delyaAwareRead
 272         // call time or may happen while we wait after delayRead() above.
 273         debugs(20, 3, HERE << "wont read from closing " << conn << " for " <<
 274                callback);
 275         return; // the read callback will never be called
 276     }
 277
 278     comm_read(conn, buf, amountToRead, callback);
 279 }
 280
 281 size_t
 282 StoreEntry::bytesWanted (Range<size_t> const aRange, bool ignoreDelayPools) const
 283 {
 284     if (mem_obj == NULL)
 285         return aRange.end;
 286
 287 #if URL_CHECKSUM_DEBUG
 288
 289     mem_obj->checkUrlChecksum();
 290
 291 #endif
 292
 293     if (!mem_obj->readAheadPolicyCanRead())
 294         return 0;
 295
 296     return mem_obj->mostBytesWanted(aRange.end, ignoreDelayPools);
 297 }
 298
 299 bool
 300 StoreEntry::checkDeferRead(int fd) const
 301 {
 302     return (bytesWanted(Range<size_t>(0,INT_MAX)) == 0);
 303 }
 304
 305 void
 306 StoreEntry::setNoDelay (bool const newValue)
 307 {
 308     if (mem_obj)
 309         mem_obj->setNoDelay(newValue);
 310 }
 311
 312 // XXX: Type names mislead. STORE_DISK_CLIENT actually means that we should
 313 //      open swapin file, aggressively trim memory, and ignore read-ahead gap.
 314 //      It does not mean we will read from disk exclusively (or at all!).
 315 // XXX: May create STORE_DISK_CLIENT with no disk caching configured.
 316 // XXX: Collapsed clients cannot predict their type.
 317 store_client_t
 318 StoreEntry::storeClientType() const
 319 {
 320     /* The needed offset isn't in memory
 321      * XXX TODO: this is wrong for range requests
 322      * as the needed offset may *not* be 0, AND
 323      * offset 0 in the memory object is the HTTP headers.
 324      */
 325
 326     assert(mem_obj);
 327
 328     if (mem_obj->inmem_lo)
 329         return STORE_DISK_CLIENT;
 330
 331     if (EBIT_TEST(flags, ENTRY_ABORTED)) {
 332         /* I don't think we should be adding clients to aborted entries */
 333         debugs(20, DBG_IMPORTANT, "storeClientType: adding to ENTRY_ABORTED entry");
 334         return STORE_MEM_CLIENT;
 335     }
 336
 337     if (store_status == STORE_OK) {
 338         /* the object has completed. */
 339
 340         if (mem_obj->inmem_lo == 0 && !isEmpty()) {
 341             if (swap_status == SWAPOUT_DONE) {
 342                 debugs(20,7, HERE << mem_obj << " lo: " << mem_obj->inmem_lo << " hi: " << mem_obj->endOffset() << " size: " << mem_obj->object_sz);
 343                 if (mem_obj->endOffset() == mem_obj->object_sz) {
 344                     /* hot object fully swapped in (XXX: or swapped out?) */
 345                     return STORE_MEM_CLIENT;
 346                 }
 347             } else {
 348                 /* Memory-only, or currently being swapped out */
 349                 return STORE_MEM_CLIENT;
 350             }
 351         }
 352         return STORE_DISK_CLIENT;
 353     }
 354
 355     /* here and past, entry is STORE_PENDING */
 356     /*
 357      * If this is the first client, let it be the mem client
 358      */
 359     if (mem_obj->nclients == 1)
 360         return STORE_MEM_CLIENT;
 361
 362     /*
 363      * If there is no disk file to open yet, we must make this a
 364      * mem client.  If we can't open the swapin file before writing
 365      * to the client, there is no guarantee that we will be able
 366      * to open it later when we really need it.
 367      */
 368     if (swap_status == SWAPOUT_NONE)
 369         return STORE_MEM_CLIENT;
 370
 371     /*
 372      * otherwise, make subsequent clients read from disk so they
 373      * can not delay the first, and vice-versa.
 374      */
 375     return STORE_DISK_CLIENT;
 376 }
 377
 378 StoreEntry::StoreEntry() :
 379         mem_obj(NULL),
 380         timestamp(-1),
 381         lastref(-1),
 382         expires(-1),
 383         lastmod(-1),
 384         swap_file_sz(0),
 385         refcount(0),
 386         flags(0),
 387         swap_filen(-1),
 388         swap_dirn(-1),
 389         mem_status(NOT_IN_MEMORY),
 390         ping_status(PING_NONE),
 391         store_status(STORE_PENDING),
 392         swap_status(SWAPOUT_NONE),
 393         lock_count(0)
 394 {
 395     debugs(20, 5, "StoreEntry constructed, this=" << this);
 396 }
 397
 398 StoreEntry::~StoreEntry()
 399 {
 400     debugs(20, 5, "StoreEntry destructed, this=" << this);
 401 }
 402
 403 #if USE_ADAPTATION
 404 void
 405 StoreEntry::deferProducer(const AsyncCall::Pointer &producer)
 406 {
 407     if (!deferredProducer)
 408         deferredProducer = producer;
 409     else
 410         debugs(20, 5, HERE << "Deferred producer call is allready set to: " <<
 411                *deferredProducer << ", requested call: " << *producer);
 412 }
 413
 414 void
 415 StoreEntry::kickProducer()
 416 {
 417     if (deferredProducer != NULL) {
 418         ScheduleCallHere(deferredProducer);
 419         deferredProducer = NULL;
 420     }
 421 }
 422 #endif
 423
 424 void
 425 StoreEntry::destroyMemObject()
 426 {
 427     debugs(20, 3, HERE << "destroyMemObject " << mem_obj);
 428
 429     if (MemObject *mem = mem_obj) {
 430         // Store::Root() is FATALly missing during shutdown
 431         if (mem->xitTable.index >= 0 && !shutting_down)
 432             Store::Root().transientsDisconnect(*mem);
 433         if (mem->memCache.index >= 0 && !shutting_down)
 434             Store::Root().memoryDisconnect(*this);
 435
 436         setMemStatus(NOT_IN_MEMORY);
 437         mem_obj = NULL;
 438         delete mem;
 439     }
 440 }
 441
 442 void
 443 destroyStoreEntry(void *data)
 444 {
 445     debugs(20, 3, HERE << "destroyStoreEntry: destroying " <<  data);
 446     StoreEntry *e = static_cast<StoreEntry *>(static_cast<hash_link *>(data));
 447     assert(e != NULL);
 448
 449     if (e == NullStoreEntry::getInstance())
 450         return;
 451
 452     // Store::Root() is FATALly missing during shutdown
 453     if (e->swap_filen >= 0 && !shutting_down) {
 454         SwapDir &sd = dynamic_cast<SwapDir&>(*e->store());
 455         sd.disconnect(*e);
 456     }
 457
 458     e->destroyMemObject();
 459
 460     e->hashDelete();
 461
 462     assert(e->key == NULL);
 463
 464     delete e;
 465 }
 466
 467 /* ----- INTERFACE BETWEEN STORAGE MANAGER AND HASH TABLE FUNCTIONS --------- */
 468
 469 void
 470 StoreEntry::hashInsert(const cache_key * someKey)
 471 {
 472     debugs(20, 3, "StoreEntry::hashInsert: Inserting Entry " << *this << " key '" << storeKeyText(someKey) << "'");
 473     key = storeKeyDup(someKey);
 474     hash_join(store_table, this);
 475 }
 476
 477 void
 478 StoreEntry::hashDelete()
 479 {
 480     if (key) { // some test cases do not create keys and do not hashInsert()
 481         hash_remove_link(store_table, this);
 482         storeKeyFree((const cache_key *)key);
 483         key = NULL;
 484     }
 485 }
 486
 487 /* -------------------------------------------------------------------------- */
 488
 489 /* get rid of memory copy of the object */
 490 void
 491 StoreEntry::purgeMem()
 492 {
 493     if (mem_obj == NULL)
 494         return;
 495
 496     debugs(20, 3, "StoreEntry::purgeMem: Freeing memory-copy of " << getMD5Text());
 497
 498     Store::Root().memoryUnlink(*this);
 499
 500     if (swap_status != SWAPOUT_DONE)
 501         release();
 502 }
 503
 504 void
 505 StoreEntry::lock(const char *context)
 506 {
 507     ++lock_count;
 508     debugs(20, 3, context << " locked key " << getMD5Text() << ' ' << *this);
 509 }
 510
 511 void
 512 StoreEntry::touch()
 513 {
 514     lastref = squid_curtime;
 515     Store::Root().reference(*this);
 516 }
 517
 518 void
 519 StoreEntry::setReleaseFlag()
 520 {
 521     if (EBIT_TEST(flags, RELEASE_REQUEST))
 522         return;
 523
 524     debugs(20, 3, "StoreEntry::setReleaseFlag: '" << getMD5Text() << "'");
 525
 526     EBIT_SET(flags, RELEASE_REQUEST);
 527
 528     Store::Root().markForUnlink(*this);
 529 }
 530
 531 void
 532 StoreEntry::releaseRequest()
 533 {
 534     if (EBIT_TEST(flags, RELEASE_REQUEST))
 535         return;
 536
 537     setReleaseFlag(); // makes validToSend() false, preventing future hits
 538
 539     setPrivateKey();
 540 }
 541
 542 int
 543 StoreEntry::unlock(const char *context)
 544 {
 545     debugs(20, 3, (context ? context : "somebody") <<
 546            " unlocking key " << getMD5Text() << ' ' << *this);
 547     assert(lock_count > 0);
 548     --lock_count;
 549
 550     if (lock_count)
 551         return (int) lock_count;
 552
 553     if (store_status == STORE_PENDING)
 554         setReleaseFlag();
 555
 556     assert(storePendingNClients(this) == 0);
 557
 558     if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 559         this->release();
 560         return 0;
 561     }
 562
 563     if (EBIT_TEST(flags, KEY_PRIVATE))
 564         debugs(20, DBG_IMPORTANT, "WARNING: " << __FILE__ << ":" << __LINE__ << ": found KEY_PRIVATE");
 565
 566     Store::Root().handleIdleEntry(*this); // may delete us
 567     return 0;
 568 }
 569
 570 void
 571 StoreEntry::getPublicByRequestMethod  (StoreClient *aClient, HttpRequest * request, const HttpRequestMethod& method)
 572 {
 573     assert (aClient);
 574     StoreEntry *result = storeGetPublicByRequestMethod( request, method);
 575
 576     if (!result)
 577         aClient->created (NullStoreEntry::getInstance());
 578     else
 579         aClient->created (result);
 580 }
 581
 582 void
 583 StoreEntry::getPublicByRequest (StoreClient *aClient, HttpRequest * request)
 584 {
 585     assert (aClient);
 586     StoreEntry *result = storeGetPublicByRequest (request);
 587
 588     if (!result)
 589         result = NullStoreEntry::getInstance();
 590
 591     aClient->created (result);
 592 }
 593
 594 void
 595 StoreEntry::getPublic (StoreClient *aClient, const char *uri, const HttpRequestMethod& method)
 596 {
 597     assert (aClient);
 598     StoreEntry *result = storeGetPublic (uri, method);
 599
 600     if (!result)
 601         result = NullStoreEntry::getInstance();
 602
 603     aClient->created (result);
 604 }
 605
 606 StoreEntry *
 607 storeGetPublic(const char *uri, const HttpRequestMethod& method)
 608 {
 609     return Store::Root().get(storeKeyPublic(uri, method));
 610 }
 611
 612 StoreEntry *
 613 storeGetPublicByRequestMethod(HttpRequest * req, const HttpRequestMethod& method)
 614 {
 615     return Store::Root().get(storeKeyPublicByRequestMethod(req, method));
 616 }
 617
 618 StoreEntry *
 619 storeGetPublicByRequest(HttpRequest * req)
 620 {
 621     StoreEntry *e = storeGetPublicByRequestMethod(req, req->method);
 622
 623     if (e == NULL && req->method == Http::METHOD_HEAD)
 624         /* We can generate a HEAD reply from a cached GET object */
 625         e = storeGetPublicByRequestMethod(req, Http::METHOD_GET);
 626
 627     return e;
 628 }
 629
 630 static int
 631 getKeyCounter(void)
 632 {
 633     static int key_counter = 0;
 634
 635     if (++key_counter < 0)
 636         key_counter = 1;
 637
 638     return key_counter;
 639 }
 640
 641 /* RBC 20050104 AFAICT this should become simpler:
 642  * rather than reinserting with a special key it should be marked
 643  * as 'released' and then cleaned up when refcounting indicates.
 644  * the StoreHashIndex could well implement its 'released' in the
 645  * current manner.
 646  * Also, clean log writing should skip over ia,t
 647  * Otherwise, we need a 'remove from the index but not the store
 648  * concept'.
 649  */
 650 void
 651 StoreEntry::setPrivateKey()
 652 {
 653     const cache_key *newkey;
 654
 655     if (key && EBIT_TEST(flags, KEY_PRIVATE))
 656         return;                 /* is already private */
 657
 658     if (key) {
 659         setReleaseFlag(); // will markForUnlink(); all caches/workers will know
 660
 661         // TODO: move into SwapDir::markForUnlink() already called by Root()
 662         if (swap_filen > -1)
 663             storeDirSwapLog(this, SWAP_LOG_DEL);
 664
 665         hashDelete();
 666     }
 667
 668     if (mem_obj && mem_obj->hasUris()) {
 669         mem_obj->id = getKeyCounter();
 670         newkey = storeKeyPrivate(mem_obj->storeId(), mem_obj->method, mem_obj->id);
 671     } else {
 672         newkey = storeKeyPrivate("JUNK", Http::METHOD_NONE, getKeyCounter());
 673     }
 674
 675     assert(hash_lookup(store_table, newkey) == NULL);
 676     EBIT_SET(flags, KEY_PRIVATE);
 677     hashInsert(newkey);
 678 }
 679
 680 void
 681 StoreEntry::setPublicKey()
 682 {
 683     const cache_key *newkey;
 684
 685     if (key && !EBIT_TEST(flags, KEY_PRIVATE))
 686         return;                 /* is already public */
 687
 688     assert(mem_obj);
 689
 690     /*
 691      * We can't make RELEASE_REQUEST objects public.  Depending on
 692      * when RELEASE_REQUEST gets set, we might not be swapping out
 693      * the object.  If we're not swapping out, then subsequent
 694      * store clients won't be able to access object data which has
 695      * been freed from memory.
 696      *
 697      * If RELEASE_REQUEST is set, setPublicKey() should not be called.
 698      */
 699 #if MORE_DEBUG_OUTPUT
 700
 701     if (EBIT_TEST(flags, RELEASE_REQUEST))
 702         debugs(20, DBG_IMPORTANT, "assertion failed: RELEASE key " << key << ", url " << mem_obj->url);
 703
 704 #endif
 705
 706     assert(!EBIT_TEST(flags, RELEASE_REQUEST));
 707
 708     if (mem_obj->request) {
 709         HttpRequest *request = mem_obj->request;
 710
 711         if (!mem_obj->vary_headers) {
 712             /* First handle the case where the object no longer varies */
 713             safe_free(request->vary_headers);
 714         } else {
 715             if (request->vary_headers && strcmp(request->vary_headers, mem_obj->vary_headers) != 0) {
 716                 /* Oops.. the variance has changed. Kill the base object
 717                  * to record the new variance key
 718                  */
 719                 safe_free(request->vary_headers);       /* free old "bad" variance key */
 720                 if (StoreEntry *pe = storeGetPublic(mem_obj->storeId(), mem_obj->method))
 721                     pe->release();
 722             }
 723
 724             /* Make sure the request knows the variance status */
 725             if (!request->vary_headers) {
 726                 const char *vary = httpMakeVaryMark(request, mem_obj->getReply());
 727
 728                 if (vary)
 729                     request->vary_headers = xstrdup(vary);
 730             }
 731         }
 732
 733         // TODO: storeGetPublic() calls below may create unlocked entries.
 734         // We should add/use storeHas() API or lock/unlock those entries.
 735         if (mem_obj->vary_headers && !storeGetPublic(mem_obj->storeId(), mem_obj->method)) {
 736             /* Create "vary" base object */
 737             String vary;
 738             StoreEntry *pe = storeCreateEntry(mem_obj->storeId(), mem_obj->logUri(), request->flags, request->method);
 739             /* We are allowed to do this typecast */
 740             HttpReply *rep = new HttpReply;
 741             rep->setHeaders(Http::scOkay, "Internal marker object", "x-squid-internal/vary", -1, -1, squid_curtime + 100000);
 742             vary = mem_obj->getReply()->header.getList(HDR_VARY);
 743
 744             if (vary.size()) {
 745                 /* Again, we own this structure layout */
 746                 rep->header.putStr(HDR_VARY, vary.termedBuf());
 747                 vary.clean();
 748             }
 749
 750 #if X_ACCELERATOR_VARY
 751             vary = mem_obj->getReply()->header.getList(HDR_X_ACCELERATOR_VARY);
 752
 753             if (vary.size() > 0) {
 754                 /* Again, we own this structure layout */
 755                 rep->header.putStr(HDR_X_ACCELERATOR_VARY, vary.termedBuf());
 756                 vary.clean();
 757             }
 758
 759 #endif
 760             pe->replaceHttpReply(rep, false); // no write until key is public
 761
 762             pe->timestampsSet();
 763
 764             pe->makePublic();
 765
 766             pe->startWriting(); // after makePublic()
 767
 768             pe->complete();
 769
 770             pe->unlock("StoreEntry::setPublicKey+Vary");
 771         }
 772
 773         newkey = storeKeyPublicByRequest(mem_obj->request);
 774     } else
 775         newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 776
 777     if (StoreEntry *e2 = (StoreEntry *)hash_lookup(store_table, newkey)) {
 778         debugs(20, 3, "Making old " << *e2 << " private.");
 779         e2->setPrivateKey();
 780         e2->release();
 781
 782         if (mem_obj->request)
 783             newkey = storeKeyPublicByRequest(mem_obj->request);
 784         else
 785             newkey = storeKeyPublic(mem_obj->storeId(), mem_obj->method);
 786     }
 787
 788     if (key)
 789         hashDelete();
 790
 791     EBIT_CLR(flags, KEY_PRIVATE);
 792
 793     hashInsert(newkey);
 794
 795     if (swap_filen > -1)
 796         storeDirSwapLog(this, SWAP_LOG_ADD);
 797 }
 798
 799 StoreEntry *
 800 storeCreatePureEntry(const char *url, const char *log_url, const RequestFlags &flags, const HttpRequestMethod& method)
 801 {
 802     StoreEntry *e = NULL;
 803     debugs(20, 3, "storeCreateEntry: '" << url << "'");
 804
 805     e = new StoreEntry();
 806     e->makeMemObject();
 807     e->mem_obj->setUris(url, log_url, method);
 808
 809     if (flags.cachable) {
 810         EBIT_CLR(e->flags, RELEASE_REQUEST);
 811     } else {
 812         e->releaseRequest();
 813     }
 814
 815     e->store_status = STORE_PENDING;
 816     e->refcount = 0;
 817     e->lastref = squid_curtime;
 818     e->timestamp = -1;          /* set in StoreEntry::timestampsSet() */
 819     e->ping_status = PING_NONE;
 820     EBIT_SET(e->flags, ENTRY_VALIDATED);
 821     return e;
 822 }
 823
 824 StoreEntry *
 825 storeCreateEntry(const char *url, const char *logUrl, const RequestFlags &flags, const HttpRequestMethod& method)
 826 {
 827     StoreEntry *e = storeCreatePureEntry(url, logUrl, flags, method);
 828     e->lock("storeCreateEntry");
 829
 830     if (neighbors_do_private_keys || !flags.hierarchical)
 831         e->setPrivateKey();
 832     else
 833         e->setPublicKey();
 834
 835     return e;
 836 }
 837
 838 /* Mark object as expired */
 839 void
 840 StoreEntry::expireNow()
 841 {
 842     debugs(20, 3, "StoreEntry::expireNow: '" << getMD5Text() << "'");
 843     expires = squid_curtime;
 844 }
 845
 846 void
 847 StoreEntry::write (StoreIOBuffer writeBuffer)
 848 {
 849     assert(mem_obj != NULL);
 850     /* This assert will change when we teach the store to update */
 851     PROF_start(StoreEntry_write);
 852     assert(store_status == STORE_PENDING);
 853
 854     // XXX: caller uses content offset, but we also store headers
 855     if (const HttpReply *reply = mem_obj->getReply())
 856         writeBuffer.offset += reply->hdr_sz;
 857
 858     debugs(20, 5, "storeWrite: writing " << writeBuffer.length << " bytes for '" << getMD5Text() << "'");
 859     PROF_stop(StoreEntry_write);
 860     storeGetMemSpace(writeBuffer.length);
 861     mem_obj->write(writeBuffer);
 862
 863     if (!EBIT_TEST(flags, DELAY_SENDING))
 864         invokeHandlers();
 865 }
 866
 867 /* Append incoming data from a primary server to an entry. */
 868 void
 869 StoreEntry::append(char const *buf, int len)
 870 {
 871     assert(mem_obj != NULL);
 872     assert(len >= 0);
 873     assert(store_status == STORE_PENDING);
 874
 875     StoreIOBuffer tempBuffer;
 876     tempBuffer.data = (char *)buf;
 877     tempBuffer.length = len;
 878     /*
 879      * XXX sigh, offset might be < 0 here, but it gets "corrected"
 880      * later.  This offset crap is such a mess.
 881      */
 882     tempBuffer.offset = mem_obj->endOffset() - (getReply() ? getReply()->hdr_sz : 0);
 883     write(tempBuffer);
 884 }
 885
 886 void
 887 storeAppendPrintf(StoreEntry * e, const char *fmt,...)
 888 {
 889     va_list args;
 890     va_start(args, fmt);
 891
 892     storeAppendVPrintf(e, fmt, args);
 893     va_end(args);
 894 }
 895
 896 /* used be storeAppendPrintf and Packer */
 897 void
 898 storeAppendVPrintf(StoreEntry * e, const char *fmt, va_list vargs)
 899 {
 900     LOCAL_ARRAY(char, buf, 4096);
 901     buf[0] = '\0';
 902     vsnprintf(buf, 4096, fmt, vargs);
 903     e->append(buf, strlen(buf));
 904 }
 905
 906 struct _store_check_cachable_hist {
 907
 908     struct {
 909         int non_get;
 910         int not_entry_cachable;
 911         int wrong_content_length;
 912         int negative_cached;
 913         int too_big;
 914         int too_small;
 915         int private_key;
 916         int too_many_open_files;
 917         int too_many_open_fds;
 918     } no;
 919
 920     struct {
 921         int Default;
 922     } yes;
 923 } store_check_cachable_hist;
 924
 925 int
 926 storeTooManyDiskFilesOpen(void)
 927 {
 928     if (Config.max_open_disk_fds == 0)
 929         return 0;
 930
 931     if (store_open_disk_fd > Config.max_open_disk_fds)
 932         return 1;
 933
 934     return 0;
 935 }
 936
 937 int
 938 StoreEntry::checkTooSmall()
 939 {
 940     if (EBIT_TEST(flags, ENTRY_SPECIAL))
 941         return 0;
 942
 943     if (STORE_OK == store_status)
 944         if (mem_obj->object_sz < 0 ||
 945                 mem_obj->object_sz < Config.Store.minObjectSize)
 946             return 1;
 947     if (getReply()->content_length > -1)
 948         if (getReply()->content_length < Config.Store.minObjectSize)
 949             return 1;
 950     return 0;
 951 }
 952
 953 // TODO: remove checks already performed by swapoutPossible()
 954 // TODO: move "too many open..." checks outside -- we are called too early/late
 955 int
 956 StoreEntry::checkCachable()
 957 {
 958 #if CACHE_ALL_METHODS
 959
 960     if (mem_obj->method != Http::METHOD_GET) {
 961         debugs(20, 2, "StoreEntry::checkCachable: NO: non-GET method");
 962         ++store_check_cachable_hist.no.non_get;
 963     } else
 964 #endif
 965         if (store_status == STORE_OK && EBIT_TEST(flags, ENTRY_BAD_LENGTH)) {
 966             debugs(20, 2, "StoreEntry::checkCachable: NO: wrong content-length");
 967             ++store_check_cachable_hist.no.wrong_content_length;
 968         } else if (EBIT_TEST(flags, RELEASE_REQUEST)) {
 969             debugs(20, 2, "StoreEntry::checkCachable: NO: not cachable");
 970             ++store_check_cachable_hist.no.not_entry_cachable; // TODO: rename?
 971         } else if (EBIT_TEST(flags, ENTRY_NEGCACHED)) {
 972             debugs(20, 3, "StoreEntry::checkCachable: NO: negative cached");
 973             ++store_check_cachable_hist.no.negative_cached;
 974             return 0;           /* avoid release call below */
 975         } else if ((getReply()->content_length > 0 &&
 976                     getReply()->content_length > store_maxobjsize) ||
 977                    mem_obj->endOffset() > store_maxobjsize) {
 978             debugs(20, 2, "StoreEntry::checkCachable: NO: too big");
 979             ++store_check_cachable_hist.no.too_big;
 980         } else if (checkTooSmall()) {
 981             debugs(20, 2, "StoreEntry::checkCachable: NO: too small");
 982             ++store_check_cachable_hist.no.too_small;
 983         } else if (EBIT_TEST(flags, KEY_PRIVATE)) {
 984             debugs(20, 3, "StoreEntry::checkCachable: NO: private key");
 985             ++store_check_cachable_hist.no.private_key;
 986         } else if (swap_status != SWAPOUT_NONE) {
 987             /*
 988              * here we checked the swap_status because the remaining
 989              * cases are only relevant only if we haven't started swapping
 990              * out the object yet.
 991              */
 992             return 1;
 993         } else if (storeTooManyDiskFilesOpen()) {
 994             debugs(20, 2, "StoreEntry::checkCachable: NO: too many disk files open");
 995             ++store_check_cachable_hist.no.too_many_open_files;
 996         } else if (fdNFree() < RESERVED_FD) {
 997             debugs(20, 2, "StoreEntry::checkCachable: NO: too many FD's open");
 998             ++store_check_cachable_hist.no.too_many_open_fds;
 999         } else {
1000             ++store_check_cachable_hist.yes.Default;
1001             return 1;
1002         }
1003
1004     releaseRequest();
1005     return 0;
1006 }
1007
1008 void
1009 storeCheckCachableStats(StoreEntry *sentry)
1010 {
1011     storeAppendPrintf(sentry, "Category\t Count\n");
1012
1013 #if CACHE_ALL_METHODS
1014
1015     storeAppendPrintf(sentry, "no.non_get\t%d\n",
1016                       store_check_cachable_hist.no.non_get);
1017 #endif
1018
1019     storeAppendPrintf(sentry, "no.not_entry_cachable\t%d\n",
1020                       store_check_cachable_hist.no.not_entry_cachable);
1021     storeAppendPrintf(sentry, "no.wrong_content_length\t%d\n",
1022                       store_check_cachable_hist.no.wrong_content_length);
1023     storeAppendPrintf(sentry, "no.negative_cached\t%d\n",
1024                       store_check_cachable_hist.no.negative_cached);
1025     storeAppendPrintf(sentry, "no.too_big\t%d\n",
1026                       store_check_cachable_hist.no.too_big);
1027     storeAppendPrintf(sentry, "no.too_small\t%d\n",
1028                       store_check_cachable_hist.no.too_small);
1029     storeAppendPrintf(sentry, "no.private_key\t%d\n",
1030                       store_check_cachable_hist.no.private_key);
1031     storeAppendPrintf(sentry, "no.too_many_open_files\t%d\n",
1032                       store_check_cachable_hist.no.too_many_open_files);
1033     storeAppendPrintf(sentry, "no.too_many_open_fds\t%d\n",
1034                       store_check_cachable_hist.no.too_many_open_fds);
1035     storeAppendPrintf(sentry, "yes.default\t%d\n",
1036                       store_check_cachable_hist.yes.Default);
1037 }
1038
1039 void
1040 StoreEntry::complete()
1041 {
1042     debugs(20, 3, "storeComplete: '" << getMD5Text() << "'");
1043
1044     if (store_status != STORE_PENDING) {
1045         /*
1046          * if we're not STORE_PENDING, then probably we got aborted
1047          * and there should be NO clients on this entry
1048          */
1049         assert(EBIT_TEST(flags, ENTRY_ABORTED));
1050         assert(mem_obj->nclients == 0);
1051         return;
1052     }
1053
1054     /* This is suspect: mem obj offsets include the headers. do we adjust for that
1055      * in use of object_sz?
1056      */
1057     mem_obj->object_sz = mem_obj->endOffset();
1058
1059     store_status = STORE_OK;
1060
1061     assert(mem_status == NOT_IN_MEMORY);
1062
1063     if (!validLength()) {
1064         EBIT_SET(flags, ENTRY_BAD_LENGTH);
1065         releaseRequest();
1066     }
1067
1068 #if USE_CACHE_DIGESTS
1069     if (mem_obj->request)
1070         mem_obj->request->hier.store_complete_stop = current_time;
1071
1072 #endif
1073     /*
1074      * We used to call invokeHandlers, then storeSwapOut.  However,
1075      * Madhukar Reddy <myreddy@persistence.com> reported that
1076      * responses without content length would sometimes get released
1077      * in client_side, thinking that the response is incomplete.
1078      */
1079     invokeHandlers();
1080 }
1081
1082 /*
1083  * Someone wants to abort this transfer.  Set the reason in the
1084  * request structure, call the server-side callback and mark the
1085  * entry for releasing
1086  */
1087 void
1088 StoreEntry::abort()
1089 {
1090     ++statCounter.aborted_requests;
1091     assert(store_status == STORE_PENDING);
1092     assert(mem_obj != NULL);
1093     debugs(20, 6, "storeAbort: " << getMD5Text());
1094
1095     lock("StoreEntry::abort");         /* lock while aborting */
1096     negativeCache();
1097
1098     releaseRequest();
1099
1100     EBIT_SET(flags, ENTRY_ABORTED);
1101
1102     setMemStatus(NOT_IN_MEMORY);
1103
1104     store_status = STORE_OK;
1105
1106     /* Notify the server side */
1107
1108     /*
1109      * DPW 2007-05-07
1110      * Should we check abort.data for validity?
1111      */
1112     if (mem_obj->abort.callback) {
1113         if (!cbdataReferenceValid(mem_obj->abort.data))
1114             debugs(20, DBG_IMPORTANT,HERE << "queueing event when abort.data is not valid");
1115         eventAdd("mem_obj->abort.callback",
1116                  mem_obj->abort.callback,
1117                  mem_obj->abort.data,
1118                  0.0,
1119                  true);
1120         unregisterAbort();
1121     }
1122
1123     /* XXX Should we reverse these two, so that there is no
1124      * unneeded disk swapping triggered?
1125      */
1126     /* Notify the client side */
1127     invokeHandlers();
1128
1129     // abort swap out, invalidating what was created so far (release follows)
1130     swapOutFileClose(StoreIOState::writerGone);
1131
1132     unlock("StoreEntry::abort");       /* unlock */
1133 }
1134
1135 /**
1136  * Clear Memory storage to accommodate the given object len
1137  */
1138 void
1139 storeGetMemSpace(int size)
1140 {
1141     PROF_start(storeGetMemSpace);
1142     StoreEntry *e = NULL;
1143     int released = 0;
1144     static time_t last_check = 0;
1145     size_t pages_needed;
1146     RemovalPurgeWalker *walker;
1147
1148     if (squid_curtime == last_check) {
1149         PROF_stop(storeGetMemSpace);
1150         return;
1151     }
1152
1153     last_check = squid_curtime;
1154
1155     pages_needed = (size + SM_PAGE_SIZE-1) / SM_PAGE_SIZE;
1156
1157     if (mem_node::InUseCount() + pages_needed < store_pages_max) {
1158         PROF_stop(storeGetMemSpace);
1159         return;
1160     }
1161
1162     debugs(20, 2, "storeGetMemSpace: Starting, need " << pages_needed <<
1163            " pages");
1164
1165     /* XXX what to set as max_scan here? */
1166     walker = mem_policy->PurgeInit(mem_policy, 100000);
1167
1168     while ((e = walker->Next(walker))) {
1169         e->purgeMem();
1170         ++released;
1171
1172         if (mem_node::InUseCount() + pages_needed < store_pages_max)
1173             break;
1174     }
1175
1176     walker->Done(walker);
1177     debugs(20, 3, "storeGetMemSpace stats:");
1178     debugs(20, 3, "  " << std::setw(6) << hot_obj_count  << " HOT objects");
1179     debugs(20, 3, "  " << std::setw(6) << released  << " were released");
1180     PROF_stop(storeGetMemSpace);
1181 }
1182
1183 /* thunk through to Store::Root().maintain(). Note that this would be better still
1184  * if registered against the root store itself, but that requires more complex
1185  * update logic - bigger fish to fry first. Long term each store when
1186  * it becomes active will self register
1187  */
1188 void
1189 Store::Maintain(void *notused)
1190 {
1191     Store::Root().maintain();
1192
1193     /* Reregister a maintain event .. */
1194     eventAdd("MaintainSwapSpace", Maintain, NULL, 1.0, 1);
1195
1196 }
1197
1198 /* The maximum objects to scan for maintain storage space */
1199 #define MAINTAIN_MAX_SCAN       1024
1200 #define MAINTAIN_MAX_REMOVE     64
1201
1202 /*
1203  * This routine is to be called by main loop in main.c.
1204  * It removes expired objects on only one bucket for each time called.
1205  *
1206  * This should get called 1/s from main().
1207  */
1208 void
1209 StoreController::maintain()
1210 {
1211     static time_t last_warn_time = 0;
1212
1213     PROF_start(storeMaintainSwapSpace);
1214     swapDir->maintain();
1215
1216     /* this should be emitted by the oversize dir, not globally */
1217
1218     if (Store::Root().currentSize() > Store::Root().maxSize()) {
1219         if (squid_curtime - last_warn_time > 10) {
1220             debugs(20, DBG_CRITICAL, "WARNING: Disk space over limit: "
1221                    << Store::Root().currentSize() / 1024.0 << " KB > "
1222                    << (Store::Root().maxSize() >> 10) << " KB");
1223             last_warn_time = squid_curtime;
1224         }
1225     }
1226
1227     PROF_stop(storeMaintainSwapSpace);
1228 }
1229
1230 /* release an object from a cache */
1231 void
1232 StoreEntry::release()
1233 {
1234     PROF_start(storeRelease);
1235     debugs(20, 3, "releasing " << *this << ' ' << getMD5Text());
1236     /* If, for any reason we can't discard this object because of an
1237      * outstanding request, mark it for pending release */
1238
1239     if (locked()) {
1240         expireNow();
1241         debugs(20, 3, "storeRelease: Only setting RELEASE_REQUEST bit");
1242         releaseRequest();
1243         PROF_stop(storeRelease);
1244         return;
1245     }
1246
1247     Store::Root().memoryUnlink(*this);
1248
1249     if (StoreController::store_dirs_rebuilding && swap_filen > -1) {
1250         setPrivateKey();
1251
1252         if (swap_filen > -1) {
1253             // lock the entry until rebuilding is done
1254             lock("storeLateRelease");
1255             setReleaseFlag();
1256             LateReleaseStack.push_back(this);
1257         } else {
1258             destroyStoreEntry(static_cast<hash_link *>(this));
1259             // "this" is no longer valid
1260         }
1261
1262         PROF_stop(storeRelease);
1263         return;
1264     }
1265
1266     storeLog(STORE_LOG_RELEASE, this);
1267
1268     if (swap_filen > -1) {
1269         // log before unlink() below clears swap_filen
1270         if (!EBIT_TEST(flags, KEY_PRIVATE))
1271             storeDirSwapLog(this, SWAP_LOG_DEL);
1272
1273         unlink();
1274     }
1275
1276     destroyStoreEntry(static_cast<hash_link *>(this));
1277     PROF_stop(storeRelease);
1278 }
1279
1280 static void
1281 storeLateRelease(void *unused)
1282 {
1283     StoreEntry *e;
1284     int i;
1285     static int n = 0;
1286
1287     if (StoreController::store_dirs_rebuilding) {
1288         eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1289         return;
1290     }
1291
1292     for (i = 0; i < 10; ++i) {
1293         e = LateReleaseStack.count ? LateReleaseStack.pop() : NULL;
1294
1295         if (e == NULL) {
1296             /* done! */
1297             debugs(20, DBG_IMPORTANT, "storeLateRelease: released " << n << " objects");
1298             return;
1299         }
1300
1301         e->unlock("storeLateRelease");
1302         ++n;
1303     }
1304
1305     eventAdd("storeLateRelease", storeLateRelease, NULL, 0.0, 1);
1306 }
1307
1308 /* return 1 if a store entry is locked */
1309 int
1310 StoreEntry::locked() const
1311 {
1312     if (lock_count)
1313         return 1;
1314
1315     /*
1316      * SPECIAL, PUBLIC entries should be "locked";
1317      * XXX: Their owner should lock them then instead of relying on this hack.
1318      */
1319     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1320         if (!EBIT_TEST(flags, KEY_PRIVATE))
1321             return 1;
1322
1323     return 0;
1324 }
1325
1326 bool
1327 StoreEntry::validLength() const
1328 {
1329     int64_t diff;
1330     const HttpReply *reply;
1331     assert(mem_obj != NULL);
1332     reply = getReply();
1333     debugs(20, 3, "storeEntryValidLength: Checking '" << getMD5Text() << "'");
1334     debugs(20, 5, "storeEntryValidLength:     object_len = " <<
1335            objectLen());
1336     debugs(20, 5, "storeEntryValidLength:         hdr_sz = " << reply->hdr_sz);
1337     debugs(20, 5, "storeEntryValidLength: content_length = " << reply->content_length);
1338
1339     if (reply->content_length < 0) {
1340         debugs(20, 5, "storeEntryValidLength: Unspecified content length: " << getMD5Text());
1341         return 1;
1342     }
1343
1344     if (reply->hdr_sz == 0) {
1345         debugs(20, 5, "storeEntryValidLength: Zero header size: " << getMD5Text());
1346         return 1;
1347     }
1348
1349     if (mem_obj->method == Http::METHOD_HEAD) {
1350         debugs(20, 5, "storeEntryValidLength: HEAD request: " << getMD5Text());
1351         return 1;
1352     }
1353
1354     if (reply->sline.status() == Http::scNotModified)
1355         return 1;
1356
1357     if (reply->sline.status() == Http::scNoContent)
1358         return 1;
1359
1360     diff = reply->hdr_sz + reply->content_length - objectLen();
1361
1362     if (diff == 0)
1363         return 1;
1364
1365     debugs(20, 3, "storeEntryValidLength: " << (diff < 0 ? -diff : diff)  << " bytes too " << (diff < 0 ? "big" : "small") <<"; '" << getMD5Text() << "'" );
1366
1367     return 0;
1368 }
1369
1370 static void
1371 storeRegisterWithCacheManager(void)
1372 {
1373     Mgr::RegisterAction("storedir", "Store Directory Stats", Store::Stats, 0, 1);
1374     Mgr::RegisterAction("store_io", "Store IO Interface Stats", &Mgr::StoreIoAction::Create, 0, 1);
1375     Mgr::RegisterAction("store_check_cachable_stats", "storeCheckCachable() Stats",
1376                         storeCheckCachableStats, 0, 1);
1377 }
1378
1379 void
1380 storeInit(void)
1381 {
1382     storeKeyInit();
1383     mem_policy = createRemovalPolicy(Config.memPolicy);
1384     storeDigestInit();
1385     storeLogOpen();
1386     eventAdd("storeLateRelease", storeLateRelease, NULL, 1.0, 1);
1387     Store::Root().init();
1388     storeRebuildStart();
1389
1390     storeRegisterWithCacheManager();
1391 }
1392
1393 void
1394 storeConfigure(void)
1395 {
1396     store_swap_high = (long) (((float) Store::Root().maxSize() *
1397                                (float) Config.Swap.highWaterMark) / (float) 100);
1398     store_swap_low = (long) (((float) Store::Root().maxSize() *
1399                               (float) Config.Swap.lowWaterMark) / (float) 100);
1400     store_pages_max = Config.memMaxSize / sizeof(mem_node);
1401 }
1402
1403 bool
1404 StoreEntry::memoryCachable() const
1405 {
1406     if (mem_obj == NULL)
1407         return 0;
1408
1409     if (mem_obj->data_hdr.size() == 0)
1410         return 0;
1411
1412     if (mem_obj->inmem_lo != 0)
1413         return 0;
1414
1415     if (!Config.onoff.memory_cache_first && swap_status == SWAPOUT_DONE && refcount == 1)
1416         return 0;
1417
1418     return 1;
1419 }
1420
1421 int
1422 StoreEntry::checkNegativeHit() const
1423 {
1424     if (!EBIT_TEST(flags, ENTRY_NEGCACHED))
1425         return 0;
1426
1427     if (expires <= squid_curtime)
1428         return 0;
1429
1430     if (store_status != STORE_OK)
1431         return 0;
1432
1433     return 1;
1434 }
1435
1436 /**
1437  * Set object for negative caching.
1438  * Preserves any expiry information given by the server.
1439  * In absence of proper expiry info it will set to expire immediately,
1440  * or with HTTP-violations enabled the configured negative-TTL is observed
1441  */
1442 void
1443 StoreEntry::negativeCache()
1444 {
1445     // XXX: should make the default for expires 0 instead of -1
1446     //      so we can distinguish "Expires: -1" from nothing.
1447     if (expires <= 0)
1448 #if USE_HTTP_VIOLATIONS
1449         expires = squid_curtime + Config.negativeTtl;
1450 #else
1451         expires = squid_curtime;
1452 #endif
1453     EBIT_SET(flags, ENTRY_NEGCACHED);
1454 }
1455
1456 void
1457 storeFreeMemory(void)
1458 {
1459     Store::Root(NULL);
1460 #if USE_CACHE_DIGESTS
1461
1462     if (store_digest)
1463         cacheDigestDestroy(store_digest);
1464
1465 #endif
1466
1467     store_digest = NULL;
1468 }
1469
1470 int
1471 expiresMoreThan(time_t expires, time_t when)
1472 {
1473     if (expires < 0)            /* No Expires given */
1474         return 1;
1475
1476     return (expires > (squid_curtime + when));
1477 }
1478
1479 int
1480 StoreEntry::validToSend() const
1481 {
1482     if (EBIT_TEST(flags, RELEASE_REQUEST))
1483         return 0;
1484
1485     if (EBIT_TEST(flags, ENTRY_NEGCACHED))
1486         if (expires <= squid_curtime)
1487             return 0;
1488
1489     if (EBIT_TEST(flags, ENTRY_ABORTED))
1490         return 0;
1491
1492     // now check that the entry has a cache backing or is collapsed
1493     if (swap_filen > -1) // backed by a disk cache
1494         return 1;
1495
1496     if (swappingOut()) // will be backed by a disk cache
1497         return 1;
1498
1499     if (!mem_obj) // not backed by a memory cache and not collapsed
1500         return 0;
1501
1502     if (mem_obj->memCache.index >= 0) // backed by a shared memory cache
1503         return 0;
1504
1505     // StoreEntry::storeClientType() assumes DISK_CLIENT here, but there is no
1506     // disk cache backing so we should not rely on the store cache at all. This
1507     // is wrong for range requests that could feed off nibbled memory (XXX).
1508     if (mem_obj->inmem_lo) // in local memory cache, but got nibbled at
1509         return 0;
1510
1511     return 1;
1512 }
1513
1514 void
1515 StoreEntry::timestampsSet()
1516 {
1517     const HttpReply *reply = getReply();
1518     time_t served_date = reply->date;
1519     int age = reply->header.getInt(HDR_AGE);
1520     /* Compute the timestamp, mimicking RFC2616 section 13.2.3. */
1521     /* make sure that 0 <= served_date <= squid_curtime */
1522
1523     if (served_date < 0 || served_date > squid_curtime)
1524         served_date = squid_curtime;
1525
1526     /* Bug 1791:
1527      * If the returned Date: is more than 24 hours older than
1528      * the squid_curtime, then one of us needs to use NTP to set our
1529      * clock.  We'll pretend that our clock is right.
1530      */
1531     else if (served_date < (squid_curtime - 24 * 60 * 60) )
1532         served_date = squid_curtime;
1533
1534     /*
1535      * Compensate with Age header if origin server clock is ahead
1536      * of us and there is a cache in between us and the origin
1537      * server.  But DONT compensate if the age value is larger than
1538      * squid_curtime because it results in a negative served_date.
1539      */
1540     if (age > squid_curtime - served_date)
1541         if (squid_curtime > age)
1542             served_date = squid_curtime - age;
1543
1544     // compensate for Squid-to-server and server-to-Squid delays
1545     if (mem_obj && mem_obj->request) {
1546         const time_t request_sent =
1547             mem_obj->request->hier.peer_http_request_sent.tv_sec;
1548         if (0 < request_sent && request_sent < squid_curtime)
1549             served_date -= (squid_curtime - request_sent);
1550     }
1551
1552     if (reply->expires > 0 && reply->date > -1)
1553         expires = served_date + (reply->expires - reply->date);
1554     else
1555         expires = reply->expires;
1556
1557     lastmod = reply->last_modified;
1558
1559     timestamp = served_date;
1560 }
1561
1562 void
1563 StoreEntry::registerAbort(STABH * cb, void *data)
1564 {
1565     assert(mem_obj);
1566     assert(mem_obj->abort.callback == NULL);
1567     mem_obj->abort.callback = cb;
1568     mem_obj->abort.data = cbdataReference(data);
1569 }
1570
1571 void
1572 StoreEntry::unregisterAbort()
1573 {
1574     assert(mem_obj);
1575     if (mem_obj->abort.callback) {
1576         mem_obj->abort.callback = NULL;
1577         cbdataReferenceDone(mem_obj->abort.data);
1578     }
1579 }
1580
1581 void
1582 StoreEntry::dump(int l) const
1583 {
1584     debugs(20, l, "StoreEntry->key: " << getMD5Text());
1585     debugs(20, l, "StoreEntry->next: " << next);
1586     debugs(20, l, "StoreEntry->mem_obj: " << mem_obj);
1587     debugs(20, l, "StoreEntry->timestamp: " << timestamp);
1588     debugs(20, l, "StoreEntry->lastref: " << lastref);
1589     debugs(20, l, "StoreEntry->expires: " << expires);
1590     debugs(20, l, "StoreEntry->lastmod: " << lastmod);
1591     debugs(20, l, "StoreEntry->swap_file_sz: " << swap_file_sz);
1592     debugs(20, l, "StoreEntry->refcount: " << refcount);
1593     debugs(20, l, "StoreEntry->flags: " << storeEntryFlags(this));
1594     debugs(20, l, "StoreEntry->swap_dirn: " << swap_dirn);
1595     debugs(20, l, "StoreEntry->swap_filen: " << swap_filen);
1596     debugs(20, l, "StoreEntry->lock_count: " << lock_count);
1597     debugs(20, l, "StoreEntry->mem_status: " << mem_status);
1598     debugs(20, l, "StoreEntry->ping_status: " << ping_status);
1599     debugs(20, l, "StoreEntry->store_status: " << store_status);
1600     debugs(20, l, "StoreEntry->swap_status: " << swap_status);
1601 }
1602
1603 /*
1604  * NOTE, this function assumes only two mem states
1605  */
1606 void
1607 StoreEntry::setMemStatus(mem_status_t new_status)
1608 {
1609     if (new_status == mem_status)
1610         return;
1611
1612     // are we using a shared memory cache?
1613     if (Config.memShared && IamWorkerProcess()) {
1614         // This method was designed to update replacement policy, not to
1615         // actually purge something from the memory cache (TODO: rename?).
1616         // Shared memory cache does not have a policy that needs updates.
1617         mem_status = new_status;
1618         return;
1619     }
1620
1621     assert(mem_obj != NULL);
1622
1623     if (new_status == IN_MEMORY) {
1624         assert(mem_obj->inmem_lo == 0);
1625
1626         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1627             debugs(20, 4, "not inserting special " << *this << " into policy");
1628         } else {
1629             mem_policy->Add(mem_policy, this, &mem_obj->repl);
1630             debugs(20, 4, "inserted " << *this << " key: " << getMD5Text());
1631         }
1632
1633         ++hot_obj_count; // TODO: maintain for the shared hot cache as well
1634     } else {
1635         if (EBIT_TEST(flags, ENTRY_SPECIAL)) {
1636             debugs(20, 4, "not removing special " << *this << " from policy");
1637         } else {
1638             mem_policy->Remove(mem_policy, this, &mem_obj->repl);
1639             debugs(20, 4, "removed " << *this);
1640         }
1641
1642         --hot_obj_count;
1643     }
1644
1645     mem_status = new_status;
1646 }
1647
1648 const char *
1649 StoreEntry::url() const
1650 {
1651     if (this == NULL)
1652         return "[null_entry]";
1653     else if (mem_obj == NULL)
1654         return "[null_mem_obj]";
1655     else
1656         return mem_obj->storeId();
1657 }
1658
1659 MemObject *
1660 StoreEntry::makeMemObject()
1661 {
1662     if (!mem_obj)
1663         mem_obj = new MemObject();
1664     return mem_obj;
1665 }
1666
1667 void
1668 StoreEntry::createMemObject(const char *aUrl, const char *aLogUrl, const HttpRequestMethod &aMethod)
1669 {
1670     makeMemObject();
1671     mem_obj->setUris(aUrl, aLogUrl, aMethod);
1672 }
1673
1674 /* this just sets DELAY_SENDING */
1675 void
1676 StoreEntry::buffer()
1677 {
1678     EBIT_SET(flags, DELAY_SENDING);
1679 }
1680
1681 /* this just clears DELAY_SENDING and Invokes the handlers */
1682 void
1683 StoreEntry::flush()
1684 {
1685     if (EBIT_TEST(flags, DELAY_SENDING)) {
1686         EBIT_CLR(flags, DELAY_SENDING);
1687         invokeHandlers();
1688     }
1689 }
1690
1691 int64_t
1692 StoreEntry::objectLen() const
1693 {
1694     assert(mem_obj != NULL);
1695     return mem_obj->object_sz;
1696 }
1697
1698 int64_t
1699 StoreEntry::contentLen() const
1700 {
1701     assert(mem_obj != NULL);
1702     assert(getReply() != NULL);
1703     return objectLen() - getReply()->hdr_sz;
1704 }
1705
1706 HttpReply const *
1707 StoreEntry::getReply () const
1708 {
1709     if (NULL == mem_obj)
1710         return NULL;
1711
1712     return mem_obj->getReply();
1713 }
1714
1715 void
1716 StoreEntry::reset()
1717 {
1718     assert (mem_obj);
1719     debugs(20, 3, "StoreEntry::reset: " << url());
1720     mem_obj->reset();
1721     HttpReply *rep = (HttpReply *) getReply();       // bypass const
1722     rep->reset();
1723     expires = lastmod = timestamp = -1;
1724 }
1725
1726 /*
1727  * storeFsInit
1728  *
1729  * This routine calls the SETUP routine for each fs type.
1730  * I don't know where the best place for this is, and I'm not going to shuffle
1731  * around large chunks of code right now (that can be done once its working.)
1732  */
1733 void
1734 storeFsInit(void)
1735 {
1736     storeReplSetup();
1737 }
1738
1739 /*
1740  * called to add another store removal policy module
1741  */
1742 void
1743 storeReplAdd(const char *type, REMOVALPOLICYCREATE * create)
1744 {
1745     int i;
1746
1747     /* find the number of currently known repl types */
1748     for (i = 0; storerepl_list && storerepl_list[i].typestr; ++i) {
1749         if (strcmp(storerepl_list[i].typestr, type) == 0) {
1750             debugs(20, DBG_IMPORTANT, "WARNING: Trying to load store replacement policy " << type << " twice.");
1751             return;
1752         }
1753     }
1754
1755     /* add the new type */
1756     storerepl_list = static_cast<storerepl_entry_t *>(xrealloc(storerepl_list, (i + 2) * sizeof(storerepl_entry_t)));
1757
1758     memset(&storerepl_list[i + 1], 0, sizeof(storerepl_entry_t));
1759
1760     storerepl_list[i].typestr = type;
1761
1762     storerepl_list[i].create = create;
1763 }
1764
1765 /*
1766  * Create a removal policy instance
1767  */
1768 RemovalPolicy *
1769 createRemovalPolicy(RemovalPolicySettings * settings)
1770 {
1771     storerepl_entry_t *r;
1772
1773     for (r = storerepl_list; r && r->typestr; ++r) {
1774         if (strcmp(r->typestr, settings->type) == 0)
1775             return r->create(settings->args);
1776     }
1777
1778     debugs(20, DBG_IMPORTANT, "ERROR: Unknown policy " << settings->type);
1779     debugs(20, DBG_IMPORTANT, "ERROR: Be sure to have set cache_replacement_policy");
1780     debugs(20, DBG_IMPORTANT, "ERROR:   and memory_replacement_policy in squid.conf!");
1781     fatalf("ERROR: Unknown policy %s\n", settings->type);
1782     return NULL;                /* NOTREACHED */
1783 }
1784
1785 #if 0
1786 void
1787 storeSwapFileNumberSet(StoreEntry * e, sfileno filn)
1788 {
1789     if (e->swap_file_number == filn)
1790         return;
1791
1792     if (filn < 0) {
1793         assert(-1 == filn);
1794         storeDirMapBitReset(e->swap_file_number);
1795         storeDirLRUDelete(e);
1796         e->swap_file_number = -1;
1797     } else {
1798         assert(-1 == e->swap_file_number);
1799         storeDirMapBitSet(e->swap_file_number = filn);
1800         storeDirLRUAdd(e);
1801     }
1802 }
1803
1804 #endif
1805
1806 /*
1807  * Replace a store entry with
1808  * a new reply. This eats the reply.
1809  */
1810 void
1811 StoreEntry::replaceHttpReply(HttpReply *rep, bool andStartWriting)
1812 {
1813     debugs(20, 3, "StoreEntry::replaceHttpReply: " << url());
1814
1815     if (!mem_obj) {
1816         debugs(20, DBG_CRITICAL, "Attempt to replace object with no in-memory representation");
1817         return;
1818     }
1819
1820     mem_obj->replaceHttpReply(rep);
1821
1822     if (andStartWriting)
1823         startWriting();
1824 }
1825
1826 void
1827 StoreEntry::startWriting()
1828 {
1829     Packer p;
1830
1831     /* TODO: when we store headers serparately remove the header portion */
1832     /* TODO: mark the length of the headers ? */
1833     /* We ONLY want the headers */
1834     packerToStoreInit(&p, this);
1835
1836     assert (isEmpty());
1837     assert(mem_obj);
1838
1839     const HttpReply *rep = getReply();
1840     assert(rep);
1841
1842     rep->packHeadersInto(&p);
1843     mem_obj->markEndOfReplyHeaders();
1844     EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
1845
1846     rep->body.packInto(&p);
1847
1848     packerClean(&p);
1849 }
1850
1851 char const *
1852 StoreEntry::getSerialisedMetaData()
1853 {
1854     StoreMeta *tlv_list = storeSwapMetaBuild(this);
1855     int swap_hdr_sz;
1856     char *result = storeSwapMetaPack(tlv_list, &swap_hdr_sz);
1857     storeSwapTLVFree(tlv_list);
1858     assert (swap_hdr_sz >= 0);
1859     mem_obj->swap_hdr_sz = (size_t) swap_hdr_sz;
1860     return result;
1861 }
1862
1863 void
1864 StoreEntry::trimMemory(const bool preserveSwappable)
1865 {
1866     /*
1867      * DPW 2007-05-09
1868      * Bug #1943.  We must not let go any data for IN_MEMORY
1869      * objects.  We have to wait until the mem_status changes.
1870      */
1871     if (mem_status == IN_MEMORY)
1872         return;
1873
1874     if (EBIT_TEST(flags, ENTRY_SPECIAL))
1875         return; // cannot trim because we do not load them again
1876
1877     if (preserveSwappable)
1878         mem_obj->trimSwappable();
1879     else
1880         mem_obj->trimUnSwappable();
1881
1882     debugs(88, 7, *this << " inmem_lo=" << mem_obj->inmem_lo);
1883 }
1884
1885 bool
1886 StoreEntry::modifiedSince(HttpRequest * request) const
1887 {
1888     int object_length;
1889     time_t mod_time = lastmod;
1890
1891     if (mod_time < 0)
1892         mod_time = timestamp;
1893
1894     debugs(88, 3, "modifiedSince: '" << url() << "'");
1895
1896     debugs(88, 3, "modifiedSince: mod_time = " << mod_time);
1897
1898     if (mod_time < 0)
1899         return true;
1900
1901     /* Find size of the object */
1902     object_length = getReply()->content_length;
1903
1904     if (object_length < 0)
1905         object_length = contentLen();
1906
1907     if (mod_time > request->ims) {
1908         debugs(88, 3, "--> YES: entry newer than client");
1909         return true;
1910     } else if (mod_time < request->ims) {
1911         debugs(88, 3, "-->  NO: entry older than client");
1912         return false;
1913     } else if (request->imslen < 0) {
1914         debugs(88, 3, "-->  NO: same LMT, no client length");
1915         return false;
1916     } else if (request->imslen == object_length) {
1917         debugs(88, 3, "-->  NO: same LMT, same length");
1918         return false;
1919     } else {
1920         debugs(88, 3, "--> YES: same LMT, different length");
1921         return true;
1922     }
1923 }
1924
1925 bool
1926 StoreEntry::hasEtag(ETag &etag) const
1927 {
1928     if (const HttpReply *reply = getReply()) {
1929         etag = reply->header.getETag(HDR_ETAG);
1930         if (etag.str)
1931             return true;
1932     }
1933     return false;
1934 }
1935
1936 bool
1937 StoreEntry::hasIfMatchEtag(const HttpRequest &request) const
1938 {
1939     const String reqETags = request.header.getList(HDR_IF_MATCH);
1940     return hasOneOfEtags(reqETags, false);
1941 }
1942
1943 bool
1944 StoreEntry::hasIfNoneMatchEtag(const HttpRequest &request) const
1945 {
1946     const String reqETags = request.header.getList(HDR_IF_NONE_MATCH);
1947     // weak comparison is allowed only for HEAD or full-body GET requests
1948     const bool allowWeakMatch = !request.flags.isRanged &&
1949                                 (request.method == Http::METHOD_GET || request.method == Http::METHOD_HEAD);
1950     return hasOneOfEtags(reqETags, allowWeakMatch);
1951 }
1952
1953 /// whether at least one of the request ETags matches entity ETag
1954 bool
1955 StoreEntry::hasOneOfEtags(const String &reqETags, const bool allowWeakMatch) const
1956 {
1957     const ETag repETag = getReply()->header.getETag(HDR_ETAG);
1958     if (!repETag.str)
1959         return strListIsMember(&reqETags, "*", ',');
1960
1961     bool matched = false;
1962     const char *pos = NULL;
1963     const char *item;
1964     int ilen;
1965     while (!matched && strListGetItem(&reqETags, ',', &item, &ilen, &pos)) {
1966         if (!strncmp(item, "*", ilen))
1967             matched = true;
1968         else {
1969             String str;
1970             str.append(item, ilen);
1971             ETag reqETag;
1972             if (etagParseInit(&reqETag, str.termedBuf())) {
1973                 matched = allowWeakMatch ? etagIsWeakEqual(repETag, reqETag) :
1974                           etagIsStrongEqual(repETag, reqETag);
1975             }
1976         }
1977     }
1978     return matched;
1979 }
1980
1981 SwapDir::Pointer
1982 StoreEntry::store() const
1983 {
1984     assert(0 <= swap_dirn && swap_dirn < Config.cacheSwap.n_configured);
1985     return INDEXSD(swap_dirn);
1986 }
1987
1988 void
1989 StoreEntry::unlink()
1990 {
1991     store()->unlink(*this); // implies disconnect()
1992     swap_filen = -1;
1993     swap_dirn = -1;
1994     swap_status = SWAPOUT_NONE;
1995 }
1996
1997 /*
1998  * return true if the entry is in a state where
1999  * it can accept more data (ie with write() method)
2000  */
2001 bool
2002 StoreEntry::isAccepting() const
2003 {
2004     if (STORE_PENDING != store_status)
2005         return false;
2006
2007     if (EBIT_TEST(flags, ENTRY_ABORTED))
2008         return false;
2009
2010     return true;
2011 }
2012
2013 std::ostream &operator <<(std::ostream &os, const StoreEntry &e)
2014 {
2015     os << "e:";
2016
2017     if (e.mem_obj) {
2018         if (e.mem_obj->xitTable.index > -1)
2019             os << 't' << e.mem_obj->xitTable.index;
2020         if (e.mem_obj->memCache.index > -1)
2021             os << 'm' << e.mem_obj->memCache.index;
2022     }
2023     if (e.swap_filen > -1 || e.swap_dirn > -1)
2024         os << 'd' << e.swap_filen << '@' << e.swap_dirn;
2025
2026     os << '=';
2027
2028     // print only non-default status values, using unique letters
2029     if (e.mem_status != NOT_IN_MEMORY ||
2030             e.store_status != STORE_PENDING ||
2031             e.swap_status != SWAPOUT_NONE ||
2032             e.ping_status != PING_NONE) {
2033         if (e.mem_status != NOT_IN_MEMORY) os << 'm';
2034         if (e.store_status != STORE_PENDING) os << 's';
2035         if (e.swap_status != SWAPOUT_NONE) os << 'w' << e.swap_status;
2036         if (e.ping_status != PING_NONE) os << 'p' << e.ping_status;
2037     }
2038
2039     // print only set flags, using unique letters
2040     if (e.flags) {
2041         if (EBIT_TEST(e.flags, ENTRY_SPECIAL)) os << 'S';
2042         if (EBIT_TEST(e.flags, ENTRY_REVALIDATE)) os << 'R';
2043         if (EBIT_TEST(e.flags, DELAY_SENDING)) os << 'P';
2044         if (EBIT_TEST(e.flags, RELEASE_REQUEST)) os << 'X';
2045         if (EBIT_TEST(e.flags, REFRESH_REQUEST)) os << 'F';
2046         if (EBIT_TEST(e.flags, ENTRY_DISPATCHED)) os << 'D';
2047         if (EBIT_TEST(e.flags, KEY_PRIVATE)) os << 'I';
2048         if (EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT)) os << 'W';
2049         if (EBIT_TEST(e.flags, ENTRY_NEGCACHED)) os << 'N';
2050         if (EBIT_TEST(e.flags, ENTRY_VALIDATED)) os << 'V';
2051         if (EBIT_TEST(e.flags, ENTRY_BAD_LENGTH)) os << 'L';
2052         if (EBIT_TEST(e.flags, ENTRY_ABORTED)) os << 'A';
2053     }
2054
2055     if (e.mem_obj && e.mem_obj->smpCollapsed)
2056         os << 'O';
2057
2058     return os << '/' << &e << '*' << e.locks();
2059 }
2060
2061 /* NullStoreEntry */
2062
2063 NullStoreEntry NullStoreEntry::_instance;
2064
2065 NullStoreEntry *
2066 NullStoreEntry::getInstance()
2067 {
2068     return &_instance;
2069 }
2070
2071 char const *
2072 NullStoreEntry::getMD5Text() const
2073 {
2074     return "N/A";
2075 }
2076
2077 void
2078 NullStoreEntry::operator delete(void*)
2079 {
2080     fatal ("Attempt to delete NullStoreEntry\n");
2081 }
2082
2083 char const *
2084 NullStoreEntry::getSerialisedMetaData()
2085 {
2086     return NULL;
2087 }
2088
2089 #if !_USE_INLINE_
2090 #include "Store.cci"
2091 #endif