src/adaptation/icap/ModXact.cc

   1 /*
   2  * Copyright (C) 1996-2015 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 93    ICAP (RFC 3507) Client */
  10
  11 #include "squid.h"
  12 #include "AccessLogEntry.h"
  13 #include "adaptation/Answer.h"
  14 #include "adaptation/History.h"
  15 #include "adaptation/icap/Client.h"
  16 #include "adaptation/icap/Config.h"
  17 #include "adaptation/icap/History.h"
  18 #include "adaptation/icap/Launcher.h"
  19 #include "adaptation/icap/ModXact.h"
  20 #include "adaptation/icap/ServiceRep.h"
  21 #include "adaptation/Initiator.h"
  22 #include "auth/UserRequest.h"
  23 #include "base/TextException.h"
  24 #include "base64.h"
  25 #include "comm.h"
  26 #include "comm/Connection.h"
  27 #include "err_detail_type.h"
  28 #include "http/one/TeChunkedParser.h"
  29 #include "HttpHeaderTools.h"
  30 #include "HttpMsg.h"
  31 #include "HttpReply.h"
  32 #include "HttpRequest.h"
  33 #include "SquidTime.h"
  34 #include "URL.h"
  35
  36 // flow and terminology:
  37 //     HTTP| --> receive --> encode --> write --> |network
  38 //     end | <-- send    <-- parse  <-- read  <-- |end
  39
  40 // TODO: replace gotEncapsulated() with something faster; we call it often
  41
  42 CBDATA_NAMESPACED_CLASS_INIT(Adaptation::Icap, ModXact);
  43 CBDATA_NAMESPACED_CLASS_INIT(Adaptation::Icap, ModXactLauncher);
  44
  45 static const size_t TheBackupLimit = BodyPipe::MaxCapacity;
  46
  47 Adaptation::Icap::ModXact::State::State()
  48 {
  49     memset(this, 0, sizeof(*this));
  50 }
  51
  52 Adaptation::Icap::ModXact::ModXact(HttpMsg *virginHeader,
  53                                    HttpRequest *virginCause, AccessLogEntry::Pointer &alp, Adaptation::Icap::ServiceRep::Pointer &aService):
  54     AsyncJob("Adaptation::Icap::ModXact"),
  55     Adaptation::Icap::Xaction("Adaptation::Icap::ModXact", aService),
  56     virginConsumed(0),
  57     bodyParser(NULL),
  58     canStartBypass(false), // too early
  59     protectGroupBypass(true),
  60     replyHttpHeaderSize(-1),
  61     replyHttpBodySize(-1),
  62     adaptHistoryId(-1),
  63     alMaster(alp)
  64 {
  65     assert(virginHeader);
  66
  67     virgin.setHeader(virginHeader); // sets virgin.body_pipe if needed
  68     virgin.setCause(virginCause); // may be NULL
  69
  70     // adapted header and body are initialized when we parse them
  71
  72     // writing and reading ends are handled by Adaptation::Icap::Xaction
  73
  74     // encoding
  75     // nothing to do because we are using temporary buffers
  76
  77     // parsing; TODO: do not set until we parse, see ICAPOptXact
  78     icapReply = new HttpReply;
  79     icapReply->protoPrefix = "ICAP/"; // TODO: make an IcapReply class?
  80
  81     debugs(93,7, HERE << "initialized." << status());
  82 }
  83
  84 // initiator wants us to start
  85 void Adaptation::Icap::ModXact::start()
  86 {
  87     Adaptation::Icap::Xaction::start();
  88
  89     // reserve an adaptation history slot (attempts are known at this time)
  90     Adaptation::History::Pointer ah = virginRequest().adaptLogHistory();
  91     if (ah != NULL)
  92         adaptHistoryId = ah->recordXactStart(service().cfg().key, icap_tr_start, attempts > 1);
  93
  94     estimateVirginBody(); // before virgin disappears!
  95
  96     canStartBypass = service().cfg().bypass;
  97
  98     // it is an ICAP violation to send request to a service w/o known OPTIONS
  99     // and the service may is too busy for us: honor Max-Connections and such
 100     if (service().up() && service().availableForNew())
 101         startWriting();
 102     else
 103         waitForService();
 104 }
 105
 106 void Adaptation::Icap::ModXact::waitForService()
 107 {
 108     const char *comment;
 109     Must(!state.serviceWaiting);
 110
 111     if (!service().up()) {
 112         AsyncCall::Pointer call = JobCallback(93,5,
 113                                               ConnWaiterDialer, this, Adaptation::Icap::ModXact::noteServiceReady);
 114
 115         service().callWhenReady(call);
 116         comment = "to be up";
 117     } else {
 118         //The service is unavailable because of max-connection or other reason
 119
 120         if (service().cfg().onOverload != srvWait) {
 121             // The service is overloaded, but waiting to be available prohibited by
 122             // user configuration (onOverload is set to "block" or "bypass")
 123             if (service().cfg().onOverload == srvBlock)
 124                 disableBypass("not available", true);
 125             else //if (service().cfg().onOverload == srvBypass)
 126                 canStartBypass = true;
 127
 128             disableRetries();
 129             disableRepeats("ICAP service is not available");
 130
 131             debugs(93, 7, HERE << "will not wait for the service to be available" <<
 132                    status());
 133
 134             throw TexcHere("ICAP service is not available");
 135         }
 136
 137         AsyncCall::Pointer call = JobCallback(93,5,
 138                                               ConnWaiterDialer, this, Adaptation::Icap::ModXact::noteServiceAvailable);
 139         service().callWhenAvailable(call, state.waitedForService);
 140         comment = "to be available";
 141     }
 142
 143     debugs(93, 7, HERE << "will wait for the service " << comment <<  status());
 144     state.serviceWaiting = true; // after callWhenReady() which may throw
 145     state.waitedForService = true;
 146 }
 147
 148 void Adaptation::Icap::ModXact::noteServiceReady()
 149 {
 150     Must(state.serviceWaiting);
 151     state.serviceWaiting = false;
 152
 153     if (!service().up()) {
 154         disableRetries();
 155         disableRepeats("ICAP service is unusable");
 156         throw TexcHere("ICAP service is unusable");
 157     }
 158
 159     if (service().availableForOld())
 160         startWriting();
 161     else
 162         waitForService();
 163 }
 164
 165 void Adaptation::Icap::ModXact::noteServiceAvailable()
 166 {
 167     Must(state.serviceWaiting);
 168     state.serviceWaiting = false;
 169
 170     if (service().up() && service().availableForOld())
 171         startWriting();
 172     else
 173         waitForService();
 174 }
 175
 176 void Adaptation::Icap::ModXact::startWriting()
 177 {
 178     state.writing = State::writingConnect;
 179
 180     decideOnPreview(); // must be decided before we decideOnRetries
 181     decideOnRetries();
 182
 183     openConnection();
 184 }
 185
 186 // connection with the ICAP service established
 187 void Adaptation::Icap::ModXact::handleCommConnected()
 188 {
 189     Must(state.writing == State::writingConnect);
 190
 191     startReading(); // wait for early errors from the ICAP server
 192
 193     MemBuf requestBuf;
 194     requestBuf.init();
 195
 196     makeRequestHeaders(requestBuf);
 197     debugs(93, 9, HERE << "will write" << status() << ":\n" <<
 198            (requestBuf.terminate(), requestBuf.content()));
 199
 200     // write headers
 201     state.writing = State::writingHeaders;
 202     icap_tio_start = current_time;
 203     scheduleWrite(requestBuf);
 204 }
 205
 206 void Adaptation::Icap::ModXact::handleCommWrote(size_t sz)
 207 {
 208     debugs(93, 5, HERE << "Wrote " << sz << " bytes");
 209
 210     if (state.writing == State::writingHeaders)
 211         handleCommWroteHeaders();
 212     else
 213         handleCommWroteBody();
 214 }
 215
 216 void Adaptation::Icap::ModXact::handleCommWroteHeaders()
 217 {
 218     Must(state.writing == State::writingHeaders);
 219
 220     // determine next step
 221     if (preview.enabled()) {
 222         if (preview.done())
 223             decideWritingAfterPreview("zero-size");
 224         else
 225             state.writing = State::writingPreview;
 226     } else if (virginBody.expected()) {
 227         state.writing = State::writingPrime;
 228     } else {
 229         stopWriting(true);
 230         return;
 231     }
 232
 233     writeMore();
 234 }
 235
 236 void Adaptation::Icap::ModXact::writeMore()
 237 {
 238     debugs(93, 5, HERE << "checking whether to write more" << status());
 239
 240     if (writer != NULL) // already writing something
 241         return;
 242
 243     switch (state.writing) {
 244
 245     case State::writingInit:    // waiting for service OPTIONS
 246         Must(state.serviceWaiting);
 247
 248     case State::writingConnect: // waiting for the connection to establish
 249
 250     case State::writingHeaders: // waiting for the headers to be written
 251
 252     case State::writingPaused:  // waiting for the ICAP server response
 253
 254     case State::writingReallyDone: // nothing more to write
 255         return;
 256
 257     case State::writingAlmostDone: // was waiting for the last write
 258         stopWriting(false);
 259         return;
 260
 261     case State::writingPreview:
 262         writePreviewBody();
 263         return;
 264
 265     case State::writingPrime:
 266         writePrimeBody();
 267         return;
 268
 269     default:
 270         throw TexcHere("Adaptation::Icap::ModXact in bad writing state");
 271     }
 272 }
 273
 274 void Adaptation::Icap::ModXact::writePreviewBody()
 275 {
 276     debugs(93, 8, HERE << "will write Preview body from " <<
 277            virgin.body_pipe << status());
 278     Must(state.writing == State::writingPreview);
 279     Must(virgin.body_pipe != NULL);
 280
 281     const size_t sizeMax = (size_t)virgin.body_pipe->buf().contentSize();
 282     const size_t size = min(preview.debt(), sizeMax);
 283     writeSomeBody("preview body", size);
 284
 285     // change state once preview is written
 286
 287     if (preview.done())
 288         decideWritingAfterPreview("body");
 289 }
 290
 291 /// determine state.writing after we wrote the entire preview
 292 void Adaptation::Icap::ModXact::decideWritingAfterPreview(const char *kind)
 293 {
 294     if (preview.ieof()) // nothing more to write
 295         stopWriting(true);
 296     else if (state.parsing == State::psIcapHeader) // did not get a reply yet
 297         state.writing = State::writingPaused; // wait for the ICAP server reply
 298     else
 299         stopWriting(true); // ICAP server reply implies no post-preview writing
 300
 301     debugs(93, 6, HERE << "decided on writing after " << kind << " preview" <<
 302            status());
 303 }
 304
 305 void Adaptation::Icap::ModXact::writePrimeBody()
 306 {
 307     Must(state.writing == State::writingPrime);
 308     Must(virginBodyWriting.active());
 309
 310     const size_t size = (size_t)virgin.body_pipe->buf().contentSize();
 311     writeSomeBody("prime virgin body", size);
 312
 313     if (virginBodyEndReached(virginBodyWriting)) {
 314         debugs(93, 5, HERE << "wrote entire body");
 315         stopWriting(true);
 316     }
 317 }
 318
 319 void Adaptation::Icap::ModXact::writeSomeBody(const char *label, size_t size)
 320 {
 321     Must(!writer && state.writing < state.writingAlmostDone);
 322     Must(virgin.body_pipe != NULL);
 323     debugs(93, 8, HERE << "will write up to " << size << " bytes of " <<
 324            label);
 325
 326     MemBuf writeBuf; // TODO: suggest a min size based on size and lastChunk
 327
 328     writeBuf.init(); // note: we assume that last-chunk will fit
 329
 330     const size_t writableSize = virginContentSize(virginBodyWriting);
 331     const size_t chunkSize = min(writableSize, size);
 332
 333     if (chunkSize) {
 334         debugs(93, 7, HERE << "will write " << chunkSize <<
 335                "-byte chunk of " << label);
 336
 337         openChunk(writeBuf, chunkSize, false);
 338         writeBuf.append(virginContentData(virginBodyWriting), chunkSize);
 339         closeChunk(writeBuf);
 340
 341         virginBodyWriting.progress(chunkSize);
 342         virginConsume();
 343     } else {
 344         debugs(93, 7, HERE << "has no writable " << label << " content");
 345     }
 346
 347     const bool wroteEof = virginBodyEndReached(virginBodyWriting);
 348     bool lastChunk = wroteEof;
 349     if (state.writing == State::writingPreview) {
 350         preview.wrote(chunkSize, wroteEof); // even if wrote nothing
 351         lastChunk = lastChunk || preview.done();
 352     }
 353
 354     if (lastChunk) {
 355         debugs(93, 8, HERE << "will write last-chunk of " << label);
 356         addLastRequestChunk(writeBuf);
 357     }
 358
 359     debugs(93, 7, HERE << "will write " << writeBuf.contentSize()
 360            << " raw bytes of " << label);
 361
 362     if (writeBuf.hasContent()) {
 363         scheduleWrite(writeBuf); // comm will free the chunk
 364     } else {
 365         writeBuf.clean();
 366     }
 367 }
 368
 369 void Adaptation::Icap::ModXact::addLastRequestChunk(MemBuf &buf)
 370 {
 371     const bool ieof = state.writing == State::writingPreview && preview.ieof();
 372     openChunk(buf, 0, ieof);
 373     closeChunk(buf);
 374 }
 375
 376 void Adaptation::Icap::ModXact::openChunk(MemBuf &buf, size_t chunkSize, bool ieof)
 377 {
 378     buf.appendf((ieof ? "%x; ieof\r\n" : "%x\r\n"), (int) chunkSize);
 379 }
 380
 381 void Adaptation::Icap::ModXact::closeChunk(MemBuf &buf)
 382 {
 383     buf.append(ICAP::crlf, 2); // chunk-terminating CRLF
 384 }
 385
 386 const HttpRequest &Adaptation::Icap::ModXact::virginRequest() const
 387 {
 388     const HttpRequest *request = virgin.cause ?
 389                                  virgin.cause : dynamic_cast<const HttpRequest*>(virgin.header);
 390     Must(request);
 391     return *request;
 392 }
 393
 394 // did the activity reached the end of the virgin body?
 395 bool Adaptation::Icap::ModXact::virginBodyEndReached(const Adaptation::Icap::VirginBodyAct &act) const
 396 {
 397     return
 398         !act.active() || // did all (assuming it was originally planned)
 399         !virgin.body_pipe->expectMoreAfter(act.offset()); // wont have more
 400 }
 401
 402 // the size of buffered virgin body data available for the specified activity
 403 // if this size is zero, we may be done or may be waiting for more data
 404 size_t Adaptation::Icap::ModXact::virginContentSize(const Adaptation::Icap::VirginBodyAct &act) const
 405 {
 406     Must(act.active());
 407     // asbolute start of unprocessed data
 408     const uint64_t dataStart = act.offset();
 409     // absolute end of buffered data
 410     const uint64_t dataEnd = virginConsumed + virgin.body_pipe->buf().contentSize();
 411     Must(virginConsumed <= dataStart && dataStart <= dataEnd);
 412     return static_cast<size_t>(dataEnd - dataStart);
 413 }
 414
 415 // pointer to buffered virgin body data available for the specified activity
 416 const char *Adaptation::Icap::ModXact::virginContentData(const Adaptation::Icap::VirginBodyAct &act) const
 417 {
 418     Must(act.active());
 419     const uint64_t dataStart = act.offset();
 420     Must(virginConsumed <= dataStart);
 421     return virgin.body_pipe->buf().content() + static_cast<size_t>(dataStart-virginConsumed);
 422 }
 423
 424 void Adaptation::Icap::ModXact::virginConsume()
 425 {
 426     debugs(93, 9, HERE << "consumption guards: " << !virgin.body_pipe << isRetriable <<
 427            isRepeatable << canStartBypass << protectGroupBypass);
 428
 429     if (!virgin.body_pipe)
 430         return; // nothing to consume
 431
 432     if (isRetriable)
 433         return; // do not consume if we may have to retry later
 434
 435     BodyPipe &bp = *virgin.body_pipe;
 436     const bool wantToPostpone = isRepeatable || canStartBypass || protectGroupBypass;
 437
 438     // Why > 2? HttpState does not use the last bytes in the buffer
 439     // because delayAwareRead() is arguably broken. See
 440     // HttpStateData::maybeReadVirginBody for more details.
 441     if (wantToPostpone && bp.buf().spaceSize() > 2) {
 442         // Postponing may increase memory footprint and slow the HTTP side
 443         // down. Not postponing may increase the number of ICAP errors
 444         // if the ICAP service fails. We may also use "potential" space to
 445         // postpone more aggressively. Should the trade-off be configurable?
 446         debugs(93, 8, HERE << "postponing consumption from " << bp.status());
 447         return;
 448     }
 449
 450     const size_t have = static_cast<size_t>(bp.buf().contentSize());
 451     const uint64_t end = virginConsumed + have;
 452     uint64_t offset = end;
 453
 454     debugs(93, 9, HERE << "max virgin consumption offset=" << offset <<
 455            " acts " << virginBodyWriting.active() << virginBodySending.active() <<
 456            " consumed=" << virginConsumed <<
 457            " from " << virgin.body_pipe->status());
 458
 459     if (virginBodyWriting.active())
 460         offset = min(virginBodyWriting.offset(), offset);
 461
 462     if (virginBodySending.active())
 463         offset = min(virginBodySending.offset(), offset);
 464
 465     Must(virginConsumed <= offset && offset <= end);
 466
 467     if (const size_t size = static_cast<size_t>(offset - virginConsumed)) {
 468         debugs(93, 8, HERE << "consuming " << size << " out of " << have <<
 469                " virgin body bytes");
 470         bp.consume(size);
 471         virginConsumed += size;
 472         Must(!isRetriable); // or we should not be consuming
 473         disableRepeats("consumed content");
 474         disableBypass("consumed content", true);
 475     }
 476 }
 477
 478 void Adaptation::Icap::ModXact::handleCommWroteBody()
 479 {
 480     writeMore();
 481 }
 482
 483 // Called when we do not expect to call comm_write anymore.
 484 // We may have a pending write though.
 485 // If stopping nicely, we will just wait for that pending write, if any.
 486 void Adaptation::Icap::ModXact::stopWriting(bool nicely)
 487 {
 488     if (state.writing == State::writingReallyDone)
 489         return;
 490
 491     if (writer != NULL) {
 492         if (nicely) {
 493             debugs(93, 7, HERE << "will wait for the last write" << status());
 494             state.writing = State::writingAlmostDone; // may already be set
 495             checkConsuming();
 496             return;
 497         }
 498         debugs(93, 3, HERE << "will NOT wait for the last write" << status());
 499
 500         // Comm does not have an interface to clear the writer callback nicely,
 501         // but without clearing the writer we cannot recycle the connection.
 502         // We prevent connection reuse and hope that we can handle a callback
 503         // call at any time, usually in the middle of the destruction sequence!
 504         // Somebody should add comm_remove_write_handler() to comm API.
 505         reuseConnection = false;
 506         ignoreLastWrite = true;
 507     }
 508
 509     debugs(93, 7, HERE << "will no longer write" << status());
 510     if (virginBodyWriting.active()) {
 511         virginBodyWriting.disable();
 512         virginConsume();
 513     }
 514     state.writing = State::writingReallyDone;
 515     checkConsuming();
 516 }
 517
 518 void Adaptation::Icap::ModXact::stopBackup()
 519 {
 520     if (!virginBodySending.active())
 521         return;
 522
 523     debugs(93, 7, HERE << "will no longer backup" << status());
 524     virginBodySending.disable();
 525     virginConsume();
 526 }
 527
 528 bool Adaptation::Icap::ModXact::doneAll() const
 529 {
 530     return Adaptation::Icap::Xaction::doneAll() && !state.serviceWaiting &&
 531            doneSending() &&
 532            doneReading() && state.doneWriting();
 533 }
 534
 535 void Adaptation::Icap::ModXact::startReading()
 536 {
 537     Must(haveConnection());
 538     Must(!reader);
 539     Must(!adapted.header);
 540     Must(!adapted.body_pipe);
 541
 542     // we use the same buffer for headers and body and then consume headers
 543     readMore();
 544 }
 545
 546 void Adaptation::Icap::ModXact::readMore()
 547 {
 548     if (reader != NULL || doneReading()) {
 549         debugs(93,3,HERE << "returning from readMore because reader or doneReading()");
 550         return;
 551     }
 552
 553     // do not fill readBuf if we have no space to store the result
 554     if (adapted.body_pipe != NULL &&
 555             !adapted.body_pipe->buf().hasPotentialSpace()) {
 556         debugs(93,3,HERE << "not reading because ICAP reply pipe is full");
 557         return;
 558     }
 559
 560     if (readBuf.spaceSize())
 561         scheduleRead();
 562     else
 563         debugs(93,3,HERE << "nothing to do because !readBuf.spaceSize()");
 564 }
 565
 566 // comm module read a portion of the ICAP response for us
 567 void Adaptation::Icap::ModXact::handleCommRead(size_t)
 568 {
 569     Must(!state.doneParsing());
 570     icap_tio_finish = current_time;
 571     parseMore();
 572     readMore();
 573 }
 574
 575 void Adaptation::Icap::ModXact::echoMore()
 576 {
 577     Must(state.sending == State::sendingVirgin);
 578     Must(adapted.body_pipe != NULL);
 579     Must(virginBodySending.active());
 580
 581     const size_t sizeMax = virginContentSize(virginBodySending);
 582     debugs(93,5, HERE << "will echo up to " << sizeMax << " bytes from " <<
 583            virgin.body_pipe->status());
 584     debugs(93,5, HERE << "will echo up to " << sizeMax << " bytes to   " <<
 585            adapted.body_pipe->status());
 586
 587     if (sizeMax > 0) {
 588         const size_t size = adapted.body_pipe->putMoreData(virginContentData(virginBodySending), sizeMax);
 589         debugs(93,5, HERE << "echoed " << size << " out of " << sizeMax <<
 590                " bytes");
 591         virginBodySending.progress(size);
 592         disableRepeats("echoed content");
 593         disableBypass("echoed content", true);
 594         virginConsume();
 595     }
 596
 597     if (virginBodyEndReached(virginBodySending)) {
 598         debugs(93, 5, HERE << "echoed all" << status());
 599         stopSending(true);
 600     } else {
 601         debugs(93, 5, HERE << "has " <<
 602                virgin.body_pipe->buf().contentSize() << " bytes " <<
 603                "and expects more to echo" << status());
 604         // TODO: timeout if virgin or adapted pipes are broken
 605     }
 606 }
 607
 608 bool Adaptation::Icap::ModXact::doneSending() const
 609 {
 610     return state.sending == State::sendingDone;
 611 }
 612
 613 // stop (or do not start) sending adapted message body
 614 void Adaptation::Icap::ModXact::stopSending(bool nicely)
 615 {
 616     debugs(93, 7, HERE << "Enter stop sending ");
 617     if (doneSending())
 618         return;
 619     debugs(93, 7, HERE << "Proceed with stop sending ");
 620
 621     if (state.sending != State::sendingUndecided) {
 622         debugs(93, 7, HERE << "will no longer send" << status());
 623         if (adapted.body_pipe != NULL) {
 624             virginBodySending.disable();
 625             // we may leave debts if we were echoing and the virgin
 626             // body_pipe got exhausted before we echoed all planned bytes
 627             const bool leftDebts = adapted.body_pipe->needsMoreData();
 628             stopProducingFor(adapted.body_pipe, nicely && !leftDebts);
 629         }
 630     } else {
 631         debugs(93, 7, HERE << "will not start sending" << status());
 632         Must(!adapted.body_pipe);
 633     }
 634
 635     state.sending = State::sendingDone;
 636     checkConsuming();
 637 }
 638
 639 // should be called after certain state.writing or state.sending changes
 640 void Adaptation::Icap::ModXact::checkConsuming()
 641 {
 642     // quit if we already stopped or are still using the pipe
 643     if (!virgin.body_pipe || !state.doneConsumingVirgin())
 644         return;
 645
 646     debugs(93, 7, HERE << "will stop consuming" << status());
 647     stopConsumingFrom(virgin.body_pipe);
 648 }
 649
 650 void Adaptation::Icap::ModXact::parseMore()
 651 {
 652     debugs(93, 5, "have " << readBuf.length() << " bytes to parse" << status());
 653     debugs(93, 5, "\n" << readBuf);
 654
 655     if (state.parsingHeaders())
 656         parseHeaders();
 657
 658     if (state.parsing == State::psBody)
 659         parseBody();
 660 }
 661
 662 void Adaptation::Icap::ModXact::callException(const std::exception &e)
 663 {
 664     if (!canStartBypass || isRetriable) {
 665         if (!isRetriable) {
 666             if (const TextException *te = dynamic_cast<const TextException *>(&e))
 667                 detailError(ERR_DETAIL_EXCEPTION_START + te->id());
 668             else
 669                 detailError(ERR_DETAIL_EXCEPTION_OTHER);
 670         }
 671         Adaptation::Icap::Xaction::callException(e);
 672         return;
 673     }
 674
 675     try {
 676         debugs(93, 3, HERE << "bypassing " << inCall << " exception: " <<
 677                e.what() << ' ' << status());
 678         bypassFailure();
 679     } catch (const TextException &bypassTe) {
 680         detailError(ERR_DETAIL_EXCEPTION_START + bypassTe.id());
 681         Adaptation::Icap::Xaction::callException(bypassTe);
 682     } catch (const std::exception &bypassE) {
 683         detailError(ERR_DETAIL_EXCEPTION_OTHER);
 684         Adaptation::Icap::Xaction::callException(bypassE);
 685     }
 686 }
 687
 688 void Adaptation::Icap::ModXact::bypassFailure()
 689 {
 690     disableBypass("already started to bypass", false);
 691
 692     Must(!isRetriable); // or we should not be bypassing
 693     // TODO: should the same be enforced for isRepeatable? Check icap_repeat??
 694
 695     prepEchoing();
 696
 697     startSending();
 698
 699     // end all activities associated with the ICAP server
 700
 701     stopParsing();
 702
 703     stopWriting(true); // or should we force it?
 704     if (haveConnection()) {
 705         reuseConnection = false; // be conservative
 706         cancelRead(); // may not work; and we cannot stop connecting either
 707         if (!doneWithIo())
 708             debugs(93, 7, HERE << "Warning: bypass failed to stop I/O" << status());
 709     }
 710
 711     service().noteFailure(); // we are bypassing, but this is still a failure
 712 }
 713
 714 void Adaptation::Icap::ModXact::disableBypass(const char *reason, bool includingGroupBypass)
 715 {
 716     if (canStartBypass) {
 717         debugs(93,7, HERE << "will never start bypass because " << reason);
 718         canStartBypass = false;
 719     }
 720     if (protectGroupBypass && includingGroupBypass) {
 721         debugs(93,7, HERE << "not protecting group bypass because " << reason);
 722         protectGroupBypass = false;
 723     }
 724 }
 725
 726 // note that allocation for echoing is done in handle204NoContent()
 727 void Adaptation::Icap::ModXact::maybeAllocateHttpMsg()
 728 {
 729     if (adapted.header) // already allocated
 730         return;
 731
 732     if (gotEncapsulated("res-hdr")) {
 733         adapted.setHeader(new HttpReply);
 734         setOutcome(service().cfg().method == ICAP::methodReqmod ?
 735                    xoSatisfied : xoModified);
 736     } else if (gotEncapsulated("req-hdr")) {
 737         adapted.setHeader(new HttpRequest);
 738         setOutcome(xoModified);
 739     } else
 740         throw TexcHere("Neither res-hdr nor req-hdr in maybeAllocateHttpMsg()");
 741 }
 742
 743 void Adaptation::Icap::ModXact::parseHeaders()
 744 {
 745     Must(state.parsingHeaders());
 746
 747     if (state.parsing == State::psIcapHeader) {
 748         debugs(93, 5, HERE << "parse ICAP headers");
 749         parseIcapHead();
 750     }
 751
 752     if (state.parsing == State::psHttpHeader) {
 753         debugs(93, 5, HERE << "parse HTTP headers");
 754         parseHttpHead();
 755     }
 756
 757     if (state.parsingHeaders()) { // need more data
 758         Must(mayReadMore());
 759         return;
 760     }
 761
 762     startSending();
 763 }
 764
 765 // called after parsing all headers or when bypassing an exception
 766 void Adaptation::Icap::ModXact::startSending()
 767 {
 768     disableRepeats("sent headers");
 769     disableBypass("sent headers", true);
 770     sendAnswer(Answer::Forward(adapted.header));
 771
 772     if (state.sending == State::sendingVirgin)
 773         echoMore();
 774 }
 775
 776 void Adaptation::Icap::ModXact::parseIcapHead()
 777 {
 778     Must(state.sending == State::sendingUndecided);
 779
 780     if (!parseHead(icapReply.getRaw()))
 781         return;
 782
 783     if (httpHeaderHasConnDir(&icapReply->header, "close")) {
 784         debugs(93, 5, HERE << "found connection close");
 785         reuseConnection = false;
 786     }
 787
 788     switch (icapReply->sline.status()) {
 789
 790     case Http::scContinue:
 791         handle100Continue();
 792         break;
 793
 794     case Http::scOkay:
 795     case Http::scCreated: // Symantec Scan Engine 5.0 and later when modifying HTTP msg
 796
 797         if (!validate200Ok()) {
 798             throw TexcHere("Invalid ICAP Response");
 799         } else {
 800             handle200Ok();
 801         }
 802
 803         break;
 804
 805     case Http::scNoContent:
 806         handle204NoContent();
 807         break;
 808
 809     case Http::scPartialContent:
 810         handle206PartialContent();
 811         break;
 812
 813     default:
 814         debugs(93, 5, "ICAP status " << icapReply->sline.status());
 815         handleUnknownScode();
 816         break;
 817     }
 818
 819     const HttpRequest *request = dynamic_cast<HttpRequest*>(adapted.header);
 820     if (!request)
 821         request = &virginRequest();
 822
 823     // update the cross-transactional database if needed (all status codes!)
 824     if (const char *xxName = Adaptation::Config::masterx_shared_name) {
 825         Adaptation::History::Pointer ah = request->adaptHistory(true);
 826         if (ah != NULL) { // TODO: reorder checks to avoid creating history
 827             const String val = icapReply->header.getByName(xxName);
 828             if (val.size() > 0) // XXX: HttpHeader lacks empty value detection
 829                 ah->updateXxRecord(xxName, val);
 830         }
 831     }
 832
 833     // update the adaptation plan if needed (all status codes!)
 834     if (service().cfg().routing) {
 835         String services;
 836         if (icapReply->header.getList(HDR_X_NEXT_SERVICES, &services)) {
 837             Adaptation::History::Pointer ah = request->adaptHistory(true);
 838             if (ah != NULL)
 839                 ah->updateNextServices(services);
 840         }
 841     } // TODO: else warn (occasionally!) if we got HDR_X_NEXT_SERVICES
 842
 843     // We need to store received ICAP headers for <icapLastHeader logformat option.
 844     // If we already have stored headers from previous ICAP transaction related to this
 845     // request, old headers will be replaced with the new one.
 846
 847     Adaptation::History::Pointer ah = request->adaptLogHistory();
 848     if (ah != NULL)
 849         ah->recordMeta(&icapReply->header);
 850
 851     // handle100Continue() manages state.writing on its own.
 852     // Non-100 status means the server needs no postPreview data from us.
 853     if (state.writing == State::writingPaused)
 854         stopWriting(true);
 855 }
 856
 857 bool Adaptation::Icap::ModXact::validate200Ok()
 858 {
 859     if (ICAP::methodRespmod == service().cfg().method) {
 860         if (!gotEncapsulated("res-hdr"))
 861             return false;
 862
 863         return true;
 864     }
 865
 866     if (ICAP::methodReqmod == service().cfg().method) {
 867         if (!gotEncapsulated("res-hdr") && !gotEncapsulated("req-hdr"))
 868             return false;
 869
 870         return true;
 871     }
 872
 873     return false;
 874 }
 875
 876 void Adaptation::Icap::ModXact::handle100Continue()
 877 {
 878     Must(state.writing == State::writingPaused);
 879     // server must not respond before the end of preview: we may send ieof
 880     Must(preview.enabled() && preview.done() && !preview.ieof());
 881
 882     // 100 "Continue" cancels our Preview commitment,
 883     // but not commitment to handle 204 or 206 outside Preview
 884     if (!state.allowedPostview204 && !state.allowedPostview206)
 885         stopBackup();
 886
 887     state.parsing = State::psIcapHeader; // eventually
 888     icapReply->reset();
 889
 890     state.writing = State::writingPrime;
 891
 892     writeMore();
 893 }
 894
 895 void Adaptation::Icap::ModXact::handle200Ok()
 896 {
 897     state.parsing = State::psHttpHeader;
 898     state.sending = State::sendingAdapted;
 899     stopBackup();
 900     checkConsuming();
 901 }
 902
 903 void Adaptation::Icap::ModXact::handle204NoContent()
 904 {
 905     stopParsing();
 906     prepEchoing();
 907 }
 908
 909 void Adaptation::Icap::ModXact::handle206PartialContent()
 910 {
 911     if (state.writing == State::writingPaused) {
 912         Must(preview.enabled());
 913         Must(state.allowedPreview206);
 914         debugs(93, 7, HERE << "206 inside preview");
 915     } else {
 916         Must(state.writing > State::writingPaused);
 917         Must(state.allowedPostview206);
 918         debugs(93, 7, HERE << "206 outside preview");
 919     }
 920     state.parsing = State::psHttpHeader;
 921     state.sending = State::sendingAdapted;
 922     state.readyForUob = true;
 923     checkConsuming();
 924 }
 925
 926 // Called when we receive a 204 No Content response and
 927 // when we are trying to bypass a service failure.
 928 // We actually start sending (echoig or not) in startSending.
 929 void Adaptation::Icap::ModXact::prepEchoing()
 930 {
 931     disableRepeats("preparing to echo content");
 932     disableBypass("preparing to echo content", true);
 933     setOutcome(xoEcho);
 934
 935     // We want to clone the HTTP message, but we do not want
 936     // to copy some non-HTTP state parts that HttpMsg kids carry in them.
 937     // Thus, we cannot use a smart pointer, copy constructor, or equivalent.
 938     // Instead, we simply write the HTTP message and "clone" it by parsing.
 939     // TODO: use HttpMsg::clone()!
 940
 941     HttpMsg *oldHead = virgin.header;
 942     debugs(93, 7, HERE << "cloning virgin message " << oldHead);
 943
 944     MemBuf httpBuf;
 945
 946     // write the virgin message into a memory buffer
 947     httpBuf.init();
 948     packHead(httpBuf, oldHead);
 949
 950     // allocate the adapted message and copy metainfo
 951     Must(!adapted.header);
 952     {
 953         HttpMsg::Pointer newHead;
 954         if (dynamic_cast<const HttpRequest*>(oldHead)) {
 955             newHead = new HttpRequest;
 956         } else if (dynamic_cast<const HttpReply*>(oldHead)) {
 957             newHead = new HttpReply;
 958         }
 959         Must(newHead != NULL);
 960
 961         newHead->inheritProperties(oldHead);
 962
 963         adapted.setHeader(newHead.getRaw());
 964     }
 965
 966     // parse the buffer back
 967     Http::StatusCode error = Http::scNone;
 968
 969     httpBuf.terminate(); // HttpMsg::parse requires nil-terminated buffer
 970     Must(adapted.header->parse(httpBuf.content(), httpBuf.contentSize(), true, &error));
 971
 972     if (HttpRequest *r = dynamic_cast<HttpRequest*>(adapted.header))
 973         urlCanonical(r); // parse does not set HttpRequest::canonical
 974
 975     Must(adapted.header->hdr_sz == httpBuf.contentSize()); // no leftovers
 976
 977     httpBuf.clean();
 978
 979     debugs(93, 7, HERE << "cloned virgin message " << oldHead << " to " <<
 980            adapted.header);
 981
 982     // setup adapted body pipe if needed
 983     if (oldHead->body_pipe != NULL) {
 984         debugs(93, 7, HERE << "will echo virgin body from " <<
 985                oldHead->body_pipe);
 986         if (!virginBodySending.active())
 987             virginBodySending.plan(); // will throw if not possible
 988         state.sending = State::sendingVirgin;
 989         checkConsuming();
 990
 991         // TODO: optimize: is it possible to just use the oldHead pipe and
 992         // remove ICAP from the loop? This echoing is probably a common case!
 993         makeAdaptedBodyPipe("echoed virgin response");
 994         if (oldHead->body_pipe->bodySizeKnown())
 995             adapted.body_pipe->setBodySize(oldHead->body_pipe->bodySize());
 996         debugs(93, 7, HERE << "will echo virgin body to " <<
 997                adapted.body_pipe);
 998     } else {
 999         debugs(93, 7, HERE << "no virgin body to echo");
1000         stopSending(true);
1001     }
1002 }
1003
1004 /// Called when we received use-original-body chunk extension in 206 response.
1005 /// We actually start sending (echoing or not) in startSending().
1006 void Adaptation::Icap::ModXact::prepPartialBodyEchoing(uint64_t pos)
1007 {
1008     Must(virginBodySending.active());
1009     Must(virgin.header->body_pipe != NULL);
1010
1011     setOutcome(xoPartEcho);
1012
1013     debugs(93, 7, HERE << "will echo virgin body suffix from " <<
1014            virgin.header->body_pipe << " offset " << pos );
1015
1016     // check that use-original-body=N does not point beyond buffered data
1017     const uint64_t virginDataEnd = virginConsumed +
1018                                    virgin.body_pipe->buf().contentSize();
1019     Must(pos <= virginDataEnd);
1020     virginBodySending.progress(static_cast<size_t>(pos));
1021
1022     state.sending = State::sendingVirgin;
1023     checkConsuming();
1024
1025     if (virgin.header->body_pipe->bodySizeKnown())
1026         adapted.body_pipe->expectProductionEndAfter(virgin.header->body_pipe->bodySize() - pos);
1027
1028     debugs(93, 7, HERE << "will echo virgin body suffix to " <<
1029            adapted.body_pipe);
1030
1031     // Start echoing data
1032     echoMore();
1033 }
1034
1035 void Adaptation::Icap::ModXact::handleUnknownScode()
1036 {
1037     stopParsing();
1038     stopBackup();
1039     // TODO: mark connection as "bad"
1040
1041     // Terminate the transaction; we do not know how to handle this response.
1042     throw TexcHere("Unsupported ICAP status code");
1043 }
1044
1045 void Adaptation::Icap::ModXact::parseHttpHead()
1046 {
1047     if (gotEncapsulated("res-hdr") || gotEncapsulated("req-hdr")) {
1048         replyHttpHeaderSize = 0;
1049         maybeAllocateHttpMsg();
1050
1051         if (!parseHead(adapted.header))
1052             return; // need more header data
1053
1054         if (adapted.header)
1055             replyHttpHeaderSize = adapted.header->hdr_sz;
1056
1057         if (dynamic_cast<HttpRequest*>(adapted.header)) {
1058             const HttpRequest *oldR = dynamic_cast<const HttpRequest*>(virgin.header);
1059             Must(oldR);
1060             // TODO: the adapted request did not really originate from the
1061             // client; give proxy admin an option to prevent copying of
1062             // sensitive client information here. See the following thread:
1063             // http://www.squid-cache.org/mail-archive/squid-dev/200703/0040.html
1064         }
1065
1066         // Maybe adapted.header==NULL if HttpReply and have Http 0.9 ....
1067         if (adapted.header)
1068             adapted.header->inheritProperties(virgin.header);
1069     }
1070
1071     decideOnParsingBody();
1072 }
1073
1074 // parses both HTTP and ICAP headers
1075 bool Adaptation::Icap::ModXact::parseHead(HttpMsg *head)
1076 {
1077     Must(head);
1078     debugs(93, 5, "have " << readBuf.length() << " head bytes to parse; state: " << state.parsing);
1079
1080     Http::StatusCode error = Http::scNone;
1081     // XXX: performance regression. c_str() data copies
1082     // XXX: HttpMsg::parse requires a terminated string buffer
1083     const char *tmpBuf = readBuf.c_str();
1084     const bool parsed = head->parse(tmpBuf, readBuf.length(), commEof, &error);
1085     Must(parsed || !error); // success or need more data
1086
1087     if (!parsed) { // need more data
1088         debugs(93, 5, HERE << "parse failed, need more data, return false");
1089         head->reset();
1090         return false;
1091     }
1092
1093     if (HttpRequest *r = dynamic_cast<HttpRequest*>(head))
1094         urlCanonical(r); // parse does not set HttpRequest::canonical
1095
1096     debugs(93, 5, HERE << "parse success, consume " << head->hdr_sz << " bytes, return true");
1097     readBuf.consume(head->hdr_sz);
1098     return true;
1099 }
1100
1101 void Adaptation::Icap::ModXact::decideOnParsingBody()
1102 {
1103     if (gotEncapsulated("res-body") || gotEncapsulated("req-body")) {
1104         debugs(93, 5, HERE << "expecting a body");
1105         state.parsing = State::psBody;
1106         replyHttpBodySize = 0;
1107         bodyParser = new Http1::TeChunkedParser;
1108         makeAdaptedBodyPipe("adapted response from the ICAP server");
1109         Must(state.sending == State::sendingAdapted);
1110     } else {
1111         debugs(93, 5, HERE << "not expecting a body");
1112         stopParsing();
1113         stopSending(true);
1114     }
1115 }
1116
1117 void Adaptation::Icap::ModXact::parseBody()
1118 {
1119     Must(state.parsing == State::psBody);
1120     Must(bodyParser);
1121
1122     debugs(93, 5, "have " << readBuf.length() << " body bytes to parse");
1123
1124     // the parser will throw on errors
1125     BodyPipeCheckout bpc(*adapted.body_pipe);
1126     bodyParser->setPayloadBuffer(&bpc.buf);
1127     const bool parsed = bodyParser->parse(readBuf);
1128     readBuf = bodyParser->remaining(); // sync buffers after parse
1129     bpc.checkIn();
1130
1131     debugs(93, 5, "have " << readBuf.length() << " body bytes after parsed all: " << parsed);
1132     replyHttpBodySize += adapted.body_pipe->buf().contentSize();
1133
1134     // TODO: expose BodyPipe::putSize() to make this check simpler and clearer
1135     // TODO: do we really need this if we disable when sending headers?
1136     if (adapted.body_pipe->buf().contentSize() > 0) { // parsed something sometime
1137         disableRepeats("sent adapted content");
1138         disableBypass("sent adapted content", true);
1139     }
1140
1141     if (parsed) {
1142         if (state.readyForUob && bodyParser->useOriginBody >= 0) {
1143             prepPartialBodyEchoing(
1144                 static_cast<uint64_t>(bodyParser->useOriginBody));
1145             stopParsing();
1146             return;
1147         }
1148
1149         stopParsing();
1150         stopSending(true); // the parser succeeds only if all parsed data fits
1151         return;
1152     }
1153
1154     debugs(93,3,HERE << this << " needsMoreData = " << bodyParser->needsMoreData());
1155
1156     if (bodyParser->needsMoreData()) {
1157         debugs(93,3,HERE << this);
1158         Must(mayReadMore());
1159         readMore();
1160     }
1161
1162     if (bodyParser->needsMoreSpace()) {
1163         Must(!doneSending()); // can hope for more space
1164         Must(adapted.body_pipe->buf().contentSize() > 0); // paranoid
1165         // TODO: there should be a timeout in case the sink is broken
1166         // or cannot consume partial content (while we need more space)
1167     }
1168 }
1169
1170 void Adaptation::Icap::ModXact::stopParsing()
1171 {
1172     if (state.parsing == State::psDone)
1173         return;
1174
1175     debugs(93, 7, HERE << "will no longer parse" << status());
1176
1177     delete bodyParser;
1178
1179     bodyParser = NULL;
1180
1181     state.parsing = State::psDone;
1182 }
1183
1184 // HTTP side added virgin body data
1185 void Adaptation::Icap::ModXact::noteMoreBodyDataAvailable(BodyPipe::Pointer)
1186 {
1187     writeMore();
1188
1189     if (state.sending == State::sendingVirgin)
1190         echoMore();
1191 }
1192
1193 // HTTP side sent us all virgin info
1194 void Adaptation::Icap::ModXact::noteBodyProductionEnded(BodyPipe::Pointer)
1195 {
1196     Must(virgin.body_pipe->productionEnded());
1197
1198     // push writer and sender in case we were waiting for the last-chunk
1199     writeMore();
1200
1201     if (state.sending == State::sendingVirgin)
1202         echoMore();
1203 }
1204
1205 // body producer aborted, but the initiator may still want to know
1206 // the answer, even though the HTTP message has been truncated
1207 void Adaptation::Icap::ModXact::noteBodyProducerAborted(BodyPipe::Pointer)
1208 {
1209     Must(virgin.body_pipe->productionEnded());
1210
1211     // push writer and sender in case we were waiting for the last-chunk
1212     writeMore();
1213
1214     if (state.sending == State::sendingVirgin)
1215         echoMore();
1216 }
1217
1218 // adapted body consumer wants more adapted data and
1219 // possibly freed some buffer space
1220 void Adaptation::Icap::ModXact::noteMoreBodySpaceAvailable(BodyPipe::Pointer)
1221 {
1222     if (state.sending == State::sendingVirgin)
1223         echoMore();
1224     else if (state.sending == State::sendingAdapted)
1225         parseMore();
1226     else
1227         Must(state.sending == State::sendingUndecided);
1228 }
1229
1230 // adapted body consumer aborted
1231 void Adaptation::Icap::ModXact::noteBodyConsumerAborted(BodyPipe::Pointer)
1232 {
1233     detailError(ERR_DETAIL_ICAP_XACT_BODY_CONSUMER_ABORT);
1234     mustStop("adapted body consumer aborted");
1235 }
1236
1237 Adaptation::Icap::ModXact::~ModXact()
1238 {
1239     delete bodyParser;
1240 }
1241
1242 // internal cleanup
1243 void Adaptation::Icap::ModXact::swanSong()
1244 {
1245     debugs(93, 5, HERE << "swan sings" << status());
1246
1247     stopWriting(false);
1248     stopSending(false);
1249
1250     if (theInitiator.set()) // we have not sent the answer to the initiator
1251         detailError(ERR_DETAIL_ICAP_XACT_OTHER);
1252
1253     // update adaptation history if start was called and we reserved a slot
1254     Adaptation::History::Pointer ah = virginRequest().adaptLogHistory();
1255     if (ah != NULL && adaptHistoryId >= 0)
1256         ah->recordXactFinish(adaptHistoryId);
1257
1258     Adaptation::Icap::Xaction::swanSong();
1259 }
1260
1261 void prepareLogWithRequestDetails(HttpRequest *, AccessLogEntry::Pointer &);
1262
1263 void Adaptation::Icap::ModXact::finalizeLogInfo()
1264 {
1265     HttpRequest * request_ = NULL;
1266     HttpRequest * adapted_request_ = NULL;
1267     HttpReply * reply_ = NULL;
1268     request_ = (virgin.cause? virgin.cause: dynamic_cast<HttpRequest*>(virgin.header));
1269     if (!(adapted_request_ = dynamic_cast<HttpRequest*>(adapted.header))) {
1270         adapted_request_ = request_;
1271         reply_ = dynamic_cast<HttpReply*>(adapted.header);
1272     }
1273
1274     Adaptation::Icap::History::Pointer h = (request_ ? request_->icapHistory() : NULL);
1275     Must(h != NULL); // ICAPXaction::maybeLog calls only if there is a log
1276     al.icp.opcode = ICP_INVALID;
1277     al.url = h->log_uri.termedBuf();
1278     const Adaptation::Icap::ServiceRep  &s = service();
1279     al.icap.reqMethod = s.cfg().method;
1280
1281     al.cache.caddr = request_->client_addr;
1282
1283     al.request = request_;
1284     HTTPMSGLOCK(al.request);
1285     al.adapted_request = adapted_request_;
1286     HTTPMSGLOCK(al.adapted_request);
1287
1288     if (reply_) {
1289         al.reply = reply_;
1290         HTTPMSGLOCK(al.reply);
1291     } else
1292         al.reply = NULL;
1293
1294     if (h->rfc931.size())
1295         al.cache.rfc931 = h->rfc931.termedBuf();
1296
1297 #if USE_OPENSSL
1298     if (h->ssluser.size())
1299         al.cache.ssluser = h->ssluser.termedBuf();
1300 #endif
1301     al.cache.code = h->logType;
1302     // XXX: should use icap-specific counters instead ?
1303     al.http.clientRequestSz.payloadData = h->req_sz;
1304
1305     // leave al.icap.bodyBytesRead negative if no body
1306     if (replyHttpHeaderSize >= 0 || replyHttpBodySize >= 0) {
1307         const int64_t zero = 0; // to make max() argument types the same
1308         al.icap.bodyBytesRead =
1309             max(zero, replyHttpHeaderSize) + max(zero, replyHttpBodySize);
1310     }
1311
1312     if (reply_) {
1313         al.http.code = reply_->sline.status();
1314         al.http.content_type = reply_->content_type.termedBuf();
1315         if (replyHttpBodySize >= 0) {
1316             // XXX: should use icap-specific counters instead ?
1317             al.http.clientReplySz.payloadData = replyHttpBodySize;
1318             al.http.clientReplySz.header =  reply_->hdr_sz;
1319             al.cache.highOffset = replyHttpBodySize;
1320         }
1321         //don't set al.cache.objectSize because it hasn't exist yet
1322
1323         MemBuf mb;
1324         mb.init();
1325         reply_->header.packInto(&mb);
1326         al.headers.reply = xstrdup(mb.buf);
1327         mb.clean();
1328     }
1329     prepareLogWithRequestDetails(adapted_request_, alep);
1330     Xaction::finalizeLogInfo();
1331 }
1332
1333 void Adaptation::Icap::ModXact::makeRequestHeaders(MemBuf &buf)
1334 {
1335     char ntoabuf[MAX_IPSTRLEN];
1336     /*
1337      * XXX These should use HttpHdr interfaces instead of Printfs
1338      */
1339     const Adaptation::ServiceConfig &s = service().cfg();
1340     buf.appendf("%s " SQUIDSTRINGPH " ICAP/1.0\r\n", s.methodStr(), SQUIDSTRINGPRINT(s.uri));
1341     buf.appendf("Host: " SQUIDSTRINGPH ":%d\r\n", SQUIDSTRINGPRINT(s.host), s.port);
1342     buf.appendf("Date: %s\r\n", mkrfc1123(squid_curtime));
1343
1344     if (!TheConfig.reuse_connections)
1345         buf.appendf("Connection: close\r\n");
1346
1347     const HttpRequest *request = &virginRequest();
1348
1349     // we must forward "Proxy-Authenticate" and "Proxy-Authorization"
1350     // as ICAP headers.
1351     if (virgin.header->header.has(HDR_PROXY_AUTHENTICATE)) {
1352         String vh=virgin.header->header.getByName("Proxy-Authenticate");
1353         buf.appendf("Proxy-Authenticate: " SQUIDSTRINGPH "\r\n",SQUIDSTRINGPRINT(vh));
1354     }
1355
1356     if (virgin.header->header.has(HDR_PROXY_AUTHORIZATION)) {
1357         String vh=virgin.header->header.getByName("Proxy-Authorization");
1358         buf.appendf("Proxy-Authorization: " SQUIDSTRINGPH "\r\n", SQUIDSTRINGPRINT(vh));
1359     } else if (request->extacl_user.size() > 0 && request->extacl_passwd.size() > 0) {
1360         struct base64_encode_ctx ctx;
1361         base64_encode_init(&ctx);
1362         uint8_t base64buf[base64_encode_len(MAX_LOGIN_SZ)];
1363         size_t resultLen = base64_encode_update(&ctx, base64buf, request->extacl_user.size(), reinterpret_cast<const uint8_t*>(request->extacl_user.rawBuf()));
1364         resultLen += base64_encode_update(&ctx, base64buf+resultLen, 1, reinterpret_cast<const uint8_t*>(":"));
1365         resultLen += base64_encode_update(&ctx, base64buf+resultLen, request->extacl_passwd.size(), reinterpret_cast<const uint8_t*>(request->extacl_passwd.rawBuf()));
1366         resultLen += base64_encode_final(&ctx, base64buf+resultLen);
1367         buf.appendf("Proxy-Authorization: Basic %.*s\r\n", (int)resultLen, base64buf);
1368     }
1369
1370     // share the cross-transactional database records if needed
1371     if (Adaptation::Config::masterx_shared_name) {
1372         Adaptation::History::Pointer ah = request->adaptHistory(false);
1373         if (ah != NULL) {
1374             String name, value;
1375             if (ah->getXxRecord(name, value)) {
1376                 buf.appendf(SQUIDSTRINGPH ": " SQUIDSTRINGPH "\r\n", SQUIDSTRINGPRINT(name), SQUIDSTRINGPRINT(value));
1377             }
1378         }
1379     }
1380
1381     buf.append("Encapsulated: ", 14);
1382
1383     MemBuf httpBuf;
1384
1385     httpBuf.init();
1386
1387     // build HTTP request header, if any
1388     ICAP::Method m = s.method;
1389
1390     // to simplify, we could assume that request is always available
1391
1392     if (request) {
1393         if (ICAP::methodRespmod == m)
1394             encapsulateHead(buf, "req-hdr", httpBuf, request);
1395         else if (ICAP::methodReqmod == m)
1396             encapsulateHead(buf, "req-hdr", httpBuf, virgin.header);
1397     }
1398
1399     if (ICAP::methodRespmod == m)
1400         if (const HttpMsg *prime = virgin.header)
1401             encapsulateHead(buf, "res-hdr", httpBuf, prime);
1402
1403     if (!virginBody.expected())
1404         buf.appendf("null-body=%d", (int) httpBuf.contentSize());
1405     else if (ICAP::methodReqmod == m)
1406         buf.appendf("req-body=%d", (int) httpBuf.contentSize());
1407     else
1408         buf.appendf("res-body=%d", (int) httpBuf.contentSize());
1409
1410     buf.append(ICAP::crlf, 2); // terminate Encapsulated line
1411
1412     if (preview.enabled()) {
1413         buf.appendf("Preview: %d\r\n", (int)preview.ad());
1414         if (!virginBody.expected()) // there is no body to preview
1415             finishNullOrEmptyBodyPreview(httpBuf);
1416     }
1417
1418     makeAllowHeader(buf);
1419
1420     if (TheConfig.send_client_ip && request) {
1421         Ip::Address client_addr;
1422 #if FOLLOW_X_FORWARDED_FOR
1423         if (TheConfig.use_indirect_client) {
1424             client_addr = request->indirect_client_addr;
1425         } else
1426 #endif
1427             client_addr = request->client_addr;
1428         if (!client_addr.isAnyAddr() && !client_addr.isNoAddr())
1429             buf.appendf("X-Client-IP: %s\r\n", client_addr.toStr(ntoabuf,MAX_IPSTRLEN));
1430     }
1431
1432     if (TheConfig.send_username && request)
1433         makeUsernameHeader(request, buf);
1434
1435     // Adaptation::Config::metaHeaders
1436     typedef Notes::iterator ACAMLI;
1437     for (ACAMLI i = Adaptation::Config::metaHeaders.begin(); i != Adaptation::Config::metaHeaders.end(); ++i) {
1438         HttpRequest *r = virgin.cause ?
1439                          virgin.cause : dynamic_cast<HttpRequest*>(virgin.header);
1440         Must(r);
1441
1442         HttpReply *reply = dynamic_cast<HttpReply*>(virgin.header);
1443
1444         if (const char *value = (*i)->match(r, reply, alMaster)) {
1445             buf.appendf("%s: %s\r\n", (*i)->key.termedBuf(), value);
1446             Adaptation::History::Pointer ah = request->adaptHistory(false);
1447             if (ah != NULL) {
1448                 if (ah->metaHeaders == NULL)
1449                     ah->metaHeaders = new NotePairs;
1450                 if (!ah->metaHeaders->hasPair((*i)->key.termedBuf(), value))
1451                     ah->metaHeaders->add((*i)->key.termedBuf(), value);
1452             }
1453         }
1454     }
1455
1456     // fprintf(stderr, "%s\n", buf.content());
1457
1458     buf.append(ICAP::crlf, 2); // terminate ICAP header
1459
1460     // fill icapRequest for logging
1461     Must(icapRequest->parseCharBuf(buf.content(), buf.contentSize()));
1462
1463     // start ICAP request body with encapsulated HTTP headers
1464     buf.append(httpBuf.content(), httpBuf.contentSize());
1465
1466     httpBuf.clean();
1467 }
1468
1469 // decides which Allow values to write and updates the request buffer
1470 void Adaptation::Icap::ModXact::makeAllowHeader(MemBuf &buf)
1471 {
1472     const bool allow204in = preview.enabled(); // TODO: add shouldAllow204in()
1473     const bool allow204out = state.allowedPostview204 = shouldAllow204();
1474     const bool allow206in = state.allowedPreview206 = shouldAllow206in();
1475     const bool allow206out = state.allowedPostview206 = shouldAllow206out();
1476
1477     debugs(93,9, HERE << "Allows: " << allow204in << allow204out <<
1478            allow206in << allow206out);
1479
1480     const bool allow204 = allow204in || allow204out;
1481     const bool allow206 = allow206in || allow206out;
1482
1483     if (!allow204 && !allow206)
1484         return; // nothing to do
1485
1486     if (virginBody.expected()) // if there is a virgin body, plan to send it
1487         virginBodySending.plan();
1488
1489     // writing Preview:...   means we will honor 204 inside preview
1490     // writing Allow/204     means we will honor 204 outside preview
1491     // writing Allow:206     means we will honor 206 inside preview
1492     // writing Allow:204,206 means we will honor 206 outside preview
1493     const char *allowHeader = NULL;
1494     if (allow204out && allow206)
1495         allowHeader = "Allow: 204, 206\r\n";
1496     else if (allow204out)
1497         allowHeader = "Allow: 204\r\n";
1498     else if (allow206)
1499         allowHeader = "Allow: 206\r\n";
1500
1501     if (allowHeader) { // may be nil if only allow204in is true
1502         buf.append(allowHeader, strlen(allowHeader));
1503         debugs(93,5, HERE << "Will write " << allowHeader);
1504     }
1505 }
1506
1507 void Adaptation::Icap::ModXact::makeUsernameHeader(const HttpRequest *request, MemBuf &buf)
1508 {
1509 #if USE_AUTH
1510     struct base64_encode_ctx ctx;
1511     base64_encode_init(&ctx);
1512
1513     const char *value = NULL;
1514     if (request->auth_user_request != NULL) {
1515         value = request->auth_user_request->username();
1516     } else if (request->extacl_user.size() > 0) {
1517         value = request->extacl_user.termedBuf();
1518     }
1519
1520     if (value) {
1521         if (TheConfig.client_username_encode) {
1522             uint8_t base64buf[base64_encode_len(MAX_LOGIN_SZ)];
1523             size_t resultLen = base64_encode_update(&ctx, base64buf, strlen(value), reinterpret_cast<const uint8_t*>(value));
1524             resultLen += base64_encode_final(&ctx, base64buf+resultLen);
1525             buf.appendf("%s: %.*s\r\n", TheConfig.client_username_header, (int)resultLen, base64buf);
1526         } else
1527             buf.appendf("%s: %s\r\n", TheConfig.client_username_header, value);
1528     }
1529 #endif
1530 }
1531
1532 void Adaptation::Icap::ModXact::encapsulateHead(MemBuf &icapBuf, const char *section, MemBuf &httpBuf, const HttpMsg *head)
1533 {
1534     // update ICAP header
1535     icapBuf.appendf("%s=%d, ", section, (int) httpBuf.contentSize());
1536
1537     // begin cloning
1538     HttpMsg::Pointer headClone;
1539
1540     if (const HttpRequest* old_request = dynamic_cast<const HttpRequest*>(head)) {
1541         HttpRequest::Pointer new_request(new HttpRequest);
1542         Must(old_request->canonical);
1543         urlParse(old_request->method, old_request->canonical, new_request.getRaw());
1544         new_request->http_ver = old_request->http_ver;
1545         headClone = new_request.getRaw();
1546     } else if (const HttpReply *old_reply = dynamic_cast<const HttpReply*>(head)) {
1547         HttpReply::Pointer new_reply(new HttpReply);
1548         new_reply->sline = old_reply->sline;
1549         headClone = new_reply.getRaw();
1550     }
1551     Must(headClone != NULL);
1552     headClone->inheritProperties(head);
1553
1554     HttpHeaderPos pos = HttpHeaderInitPos;
1555     HttpHeaderEntry* p_head_entry = NULL;
1556     while (NULL != (p_head_entry = head->header.getEntry(&pos)) )
1557         headClone->header.addEntry(p_head_entry->clone());
1558
1559     // end cloning
1560
1561     // remove all hop-by-hop headers from the clone
1562     headClone->header.delById(HDR_PROXY_AUTHENTICATE);
1563     headClone->header.removeHopByHopEntries();
1564
1565     // pack polished HTTP header
1566     packHead(httpBuf, headClone.getRaw());
1567
1568     // headClone unlocks and, hence, deletes the message we packed
1569 }
1570
1571 void Adaptation::Icap::ModXact::packHead(MemBuf &httpBuf, const HttpMsg *head)
1572 {
1573     head->packInto(&httpBuf, true);
1574 }
1575
1576 // decides whether to offer a preview and calculates its size
1577 void Adaptation::Icap::ModXact::decideOnPreview()
1578 {
1579     if (!TheConfig.preview_enable) {
1580         debugs(93, 5, HERE << "preview disabled by squid.conf");
1581         return;
1582     }
1583
1584     const SBuf urlPath(virginRequest().url.path());
1585     size_t wantedSize;
1586     if (!service().wantsPreview(urlPath, wantedSize)) {
1587         debugs(93, 5, "should not offer preview for " << urlPath);
1588         return;
1589     }
1590
1591     // we decided to do preview, now compute its size
1592
1593     // cannot preview more than we can backup
1594     size_t ad = min(wantedSize, TheBackupLimit);
1595
1596     if (!virginBody.expected())
1597         ad = 0;
1598     else if (virginBody.knownSize())
1599         ad = min(static_cast<uint64_t>(ad), virginBody.size()); // not more than we have
1600
1601     debugs(93, 5, HERE << "should offer " << ad << "-byte preview " <<
1602            "(service wanted " << wantedSize << ")");
1603
1604     preview.enable(ad);
1605     Must(preview.enabled());
1606 }
1607
1608 // decides whether to allow 204 responses
1609 bool Adaptation::Icap::ModXact::shouldAllow204()
1610 {
1611     if (!service().allows204())
1612         return false;
1613
1614     return canBackupEverything();
1615 }
1616
1617 // decides whether to allow 206 responses in some mode
1618 bool Adaptation::Icap::ModXact::shouldAllow206any()
1619 {
1620     return TheConfig.allow206_enable && service().allows206() &&
1621            virginBody.expected(); // no need for 206 without a body
1622 }
1623
1624 // decides whether to allow 206 responses in preview mode
1625 bool Adaptation::Icap::ModXact::shouldAllow206in()
1626 {
1627     return shouldAllow206any() && preview.enabled();
1628 }
1629
1630 // decides whether to allow 206 responses outside of preview
1631 bool Adaptation::Icap::ModXact::shouldAllow206out()
1632 {
1633     return shouldAllow206any() && canBackupEverything();
1634 }
1635
1636 // used by shouldAllow204 and decideOnRetries
1637 bool Adaptation::Icap::ModXact::canBackupEverything() const
1638 {
1639     if (!virginBody.expected())
1640         return true; // no body means no problems with backup
1641
1642     // if there is a body, check whether we can backup it all
1643
1644     if (!virginBody.knownSize())
1645         return false;
1646
1647     // or should we have a different backup limit?
1648     // note that '<' allows for 0-termination of the "full" backup buffer
1649     return virginBody.size() < TheBackupLimit;
1650 }
1651
1652 // Decide whether this transaction can be retried if pconn fails
1653 // Must be called after decideOnPreview and before openConnection()
1654 void Adaptation::Icap::ModXact::decideOnRetries()
1655 {
1656     if (!isRetriable)
1657         return; // no, already decided
1658
1659     if (preview.enabled())
1660         return; // yes, because preview provides enough guarantees
1661
1662     if (canBackupEverything())
1663         return; // yes, because we can back everything up
1664
1665     disableRetries(); // no, because we cannot back everything up
1666 }
1667
1668 // Normally, the body-writing code handles preview body. It can deal with
1669 // bodies of unexpected size, including those that turn out to be empty.
1670 // However, that code assumes that the body was expected and body control
1671 // structures were initialized. This is not the case when there is no body
1672 // or the body is known to be empty, because the virgin message will lack a
1673 // body_pipe. So we handle preview of null-body and zero-size bodies here.
1674 void Adaptation::Icap::ModXact::finishNullOrEmptyBodyPreview(MemBuf &)
1675 {
1676     Must(!virginBodyWriting.active()); // one reason we handle it here
1677     Must(!virgin.body_pipe);          // another reason we handle it here
1678     Must(!preview.ad());
1679
1680     // do not add last-chunk because our Encapsulated header says null-body
1681     // addLastRequestChunk(buf);
1682     preview.wrote(0, true);
1683
1684     Must(preview.done());
1685     Must(preview.ieof());
1686 }
1687
1688 void Adaptation::Icap::ModXact::fillPendingStatus(MemBuf &buf) const
1689 {
1690     Adaptation::Icap::Xaction::fillPendingStatus(buf);
1691
1692     if (state.serviceWaiting)
1693         buf.append("U", 1);
1694
1695     if (virgin.body_pipe != NULL)
1696         buf.append("R", 1);
1697
1698     if (haveConnection() && !doneReading())
1699         buf.append("r", 1);
1700
1701     if (!state.doneWriting() && state.writing != State::writingInit)
1702         buf.appendf("w(%d)", state.writing);
1703
1704     if (preview.enabled()) {
1705         if (!preview.done())
1706             buf.appendf("P(%d)", (int) preview.debt());
1707     }
1708
1709     if (virginBodySending.active())
1710         buf.append("B", 1);
1711
1712     if (!state.doneParsing() && state.parsing != State::psIcapHeader)
1713         buf.appendf("p(%d)", state.parsing);
1714
1715     if (!doneSending() && state.sending != State::sendingUndecided)
1716         buf.appendf("S(%d)", state.sending);
1717
1718     if (state.readyForUob)
1719         buf.append("6", 1);
1720
1721     if (canStartBypass)
1722         buf.append("Y", 1);
1723
1724     if (protectGroupBypass)
1725         buf.append("G", 1);
1726 }
1727
1728 void Adaptation::Icap::ModXact::fillDoneStatus(MemBuf &buf) const
1729 {
1730     Adaptation::Icap::Xaction::fillDoneStatus(buf);
1731
1732     if (!virgin.body_pipe)
1733         buf.append("R", 1);
1734
1735     if (state.doneWriting())
1736         buf.append("w", 1);
1737
1738     if (preview.enabled()) {
1739         if (preview.done())
1740             buf.appendf("P%s", preview.ieof() ? "(ieof)" : "");
1741     }
1742
1743     if (doneReading())
1744         buf.append("r", 1);
1745
1746     if (state.doneParsing())
1747         buf.append("p", 1);
1748
1749     if (doneSending())
1750         buf.append("S", 1);
1751 }
1752
1753 bool Adaptation::Icap::ModXact::gotEncapsulated(const char *section) const
1754 {
1755     return icapReply->header.getByNameListMember("Encapsulated",
1756             section, ',').size() > 0;
1757 }
1758
1759 // calculate whether there is a virgin HTTP body and
1760 // whether its expected size is known
1761 // TODO: rename because we do not just estimate
1762 void Adaptation::Icap::ModXact::estimateVirginBody()
1763 {
1764     // note: lack of size info may disable previews and 204s
1765
1766     HttpMsg *msg = virgin.header;
1767     Must(msg);
1768
1769     HttpRequestMethod method;
1770
1771     if (virgin.cause)
1772         method = virgin.cause->method;
1773     else if (HttpRequest *req = dynamic_cast<HttpRequest*>(msg))
1774         method = req->method;
1775     else
1776         method = Http::METHOD_NONE;
1777
1778     int64_t size;
1779     // expectingBody returns true for zero-sized bodies, but we will not
1780     // get a pipe for that body, so we treat the message as bodyless
1781     if (method != Http::METHOD_NONE && msg->expectingBody(method, size) && size) {
1782         debugs(93, 6, HERE << "expects virgin body from " <<
1783                virgin.body_pipe << "; size: " << size);
1784
1785         virginBody.expect(size);
1786         virginBodyWriting.plan();
1787
1788         // sign up as a body consumer
1789         Must(msg->body_pipe != NULL);
1790         Must(msg->body_pipe == virgin.body_pipe);
1791         Must(virgin.body_pipe->setConsumerIfNotLate(this));
1792
1793         // make sure TheBackupLimit is in-sync with the buffer size
1794         Must(TheBackupLimit <= static_cast<size_t>(msg->body_pipe->buf().max_capacity));
1795     } else {
1796         debugs(93, 6, HERE << "does not expect virgin body");
1797         Must(msg->body_pipe == NULL);
1798         checkConsuming();
1799     }
1800 }
1801
1802 void Adaptation::Icap::ModXact::makeAdaptedBodyPipe(const char *what)
1803 {
1804     Must(!adapted.body_pipe);
1805     Must(!adapted.header->body_pipe);
1806     adapted.header->body_pipe = new BodyPipe(this);
1807     adapted.body_pipe = adapted.header->body_pipe;
1808     debugs(93, 7, HERE << "will supply " << what << " via " <<
1809            adapted.body_pipe << " pipe");
1810 }
1811
1812 // TODO: Move SizedEstimate and Preview elsewhere
1813
1814 Adaptation::Icap::SizedEstimate::SizedEstimate()
1815     : theData(dtUnexpected)
1816 {}
1817
1818 void Adaptation::Icap::SizedEstimate::expect(int64_t aSize)
1819 {
1820     theData = (aSize >= 0) ? aSize : (int64_t)dtUnknown;
1821 }
1822
1823 bool Adaptation::Icap::SizedEstimate::expected() const
1824 {
1825     return theData != dtUnexpected;
1826 }
1827
1828 bool Adaptation::Icap::SizedEstimate::knownSize() const
1829 {
1830     Must(expected());
1831     return theData != dtUnknown;
1832 }
1833
1834 uint64_t Adaptation::Icap::SizedEstimate::size() const
1835 {
1836     Must(knownSize());
1837     return static_cast<uint64_t>(theData);
1838 }
1839
1840 Adaptation::Icap::VirginBodyAct::VirginBodyAct(): theStart(0), theState(stUndecided)
1841 {}
1842
1843 void Adaptation::Icap::VirginBodyAct::plan()
1844 {
1845     Must(!disabled());
1846     Must(!theStart); // not started
1847     theState = stActive;
1848 }
1849
1850 void Adaptation::Icap::VirginBodyAct::disable()
1851 {
1852     theState = stDisabled;
1853 }
1854
1855 void Adaptation::Icap::VirginBodyAct::progress(size_t size)
1856 {
1857     Must(active());
1858 #if SIZEOF_SIZE_T > 4
1859     /* always true for smaller size_t's */
1860     Must(static_cast<int64_t>(size) >= 0);
1861 #endif
1862     theStart += static_cast<int64_t>(size);
1863 }
1864
1865 uint64_t Adaptation::Icap::VirginBodyAct::offset() const
1866 {
1867     Must(active());
1868     return static_cast<uint64_t>(theStart);
1869 }
1870
1871 Adaptation::Icap::Preview::Preview(): theWritten(0), theAd(0), theState(stDisabled)
1872 {}
1873
1874 void Adaptation::Icap::Preview::enable(size_t anAd)
1875 {
1876     // TODO: check for anAd not exceeding preview size limit
1877     Must(!enabled());
1878     theAd = anAd;
1879     theState = stWriting;
1880 }
1881
1882 bool Adaptation::Icap::Preview::enabled() const
1883 {
1884     return theState != stDisabled;
1885 }
1886
1887 size_t Adaptation::Icap::Preview::ad() const
1888 {
1889     Must(enabled());
1890     return theAd;
1891 }
1892
1893 bool Adaptation::Icap::Preview::done() const
1894 {
1895     Must(enabled());
1896     return theState >= stIeof;
1897 }
1898
1899 bool Adaptation::Icap::Preview::ieof() const
1900 {
1901     Must(enabled());
1902     return theState == stIeof;
1903 }
1904
1905 size_t Adaptation::Icap::Preview::debt() const
1906 {
1907     Must(enabled());
1908     return done() ? 0 : (theAd - theWritten);
1909 }
1910
1911 void Adaptation::Icap::Preview::wrote(size_t size, bool wroteEof)
1912 {
1913     Must(enabled());
1914
1915     theWritten += size;
1916
1917     Must(theWritten <= theAd);
1918
1919     if (wroteEof)
1920         theState = stIeof; // written size is irrelevant
1921     else if (theWritten >= theAd)
1922         theState = stDone;
1923 }
1924
1925 bool Adaptation::Icap::ModXact::fillVirginHttpHeader(MemBuf &mb) const
1926 {
1927     if (virgin.header == NULL)
1928         return false;
1929
1930     virgin.header->firstLineBuf(mb);
1931
1932     return true;
1933 }
1934
1935 void Adaptation::Icap::ModXact::detailError(int errDetail)
1936 {
1937     HttpRequest *request = dynamic_cast<HttpRequest*>(adapted.header);
1938     // if no adapted request, update virgin (and inherit its properties later)
1939     // TODO: make this and HttpRequest::detailError constant, like adaptHistory
1940     if (!request)
1941         request = const_cast<HttpRequest*>(&virginRequest());
1942
1943     if (request)
1944         request->detailError(ERR_ICAP_FAILURE, errDetail);
1945 }
1946
1947 void Adaptation::Icap::ModXact::clearError()
1948 {
1949     HttpRequest *request = dynamic_cast<HttpRequest*>(adapted.header);
1950     // if no adapted request, update virgin (and inherit its properties later)
1951     if (!request)
1952         request = const_cast<HttpRequest*>(&virginRequest());
1953
1954     if (request)
1955         request->clearError();
1956 }
1957
1958 /* Adaptation::Icap::ModXactLauncher */
1959
1960 Adaptation::Icap::ModXactLauncher::ModXactLauncher(HttpMsg *virginHeader, HttpRequest *virginCause, AccessLogEntry::Pointer &alp, Adaptation::ServicePointer aService):
1961     AsyncJob("Adaptation::Icap::ModXactLauncher"),
1962     Adaptation::Icap::Launcher("Adaptation::Icap::ModXactLauncher", aService),
1963     al(alp)
1964 {
1965     virgin.setHeader(virginHeader);
1966     virgin.setCause(virginCause);
1967     updateHistory(true);
1968 }
1969
1970 Adaptation::Icap::Xaction *Adaptation::Icap::ModXactLauncher::createXaction()
1971 {
1972     Adaptation::Icap::ServiceRep::Pointer s =
1973         dynamic_cast<Adaptation::Icap::ServiceRep*>(theService.getRaw());
1974     Must(s != NULL);
1975     return new Adaptation::Icap::ModXact(virgin.header, virgin.cause, al, s);
1976 }
1977
1978 void Adaptation::Icap::ModXactLauncher::swanSong()
1979 {
1980     debugs(93, 5, HERE << "swan sings");
1981     updateHistory(false);
1982     Adaptation::Icap::Launcher::swanSong();
1983 }
1984
1985 void Adaptation::Icap::ModXactLauncher::updateHistory(bool doStart)
1986 {
1987     HttpRequest *r = virgin.cause ?
1988                      virgin.cause : dynamic_cast<HttpRequest*>(virgin.header);
1989
1990     // r should never be NULL but we play safe; TODO: add Should()
1991     if (r) {
1992         Adaptation::Icap::History::Pointer h = r->icapHistory();
1993         if (h != NULL) {
1994             if (doStart)
1995                 h->start("ICAPModXactLauncher");
1996             else
1997                 h->stop("ICAPModXactLauncher");
1998         }
1999     }
2000 }
2001