apt-pkg/depcache.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: depcache.cc,v 1.25 2001/05/27 05:36:04 jgg Exp $
   4 /* ######################################################################
   5
   6    Dependency Cache - Caches Dependency information.
   7
   8    ##################################################################### */
   9                                                                         /*}}}*/
  10 // Include Files                                                        /*{{{*/
  11 #include<config.h>
  12
  13 #include <apt-pkg/depcache.h>
  14 #include <apt-pkg/versionmatch.h>
  15 #include <apt-pkg/error.h>
  16 #include <apt-pkg/sptr.h>
  17 #include <apt-pkg/fileutl.h>
  18 #include <apt-pkg/strutl.h>
  19 #include <apt-pkg/configuration.h>
  20 #include <apt-pkg/aptconfiguration.h>
  21 #include <apt-pkg/tagfile.h>
  22 #include <apt-pkg/progress.h>
  23 #include <apt-pkg/cacheset.h>
  24 #include <apt-pkg/pkgcache.h>
  25 #include <apt-pkg/cacheiterators.h>
  26 #include <apt-pkg/cachefile.h>
  27 #include <apt-pkg/macros.h>
  28
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <list>
  32 #include <string>
  33 #include <utility>
  34 #include <vector>
  35 #include <algorithm>
  36 #include <iostream>
  37 #include <set>
  38
  39 #include <sys/stat.h>
  40
  41 #include <apti18n.h>
  42                                                                         /*}}}*/
  43
  44 using std::string;
  45
  46 // helper for Install-Recommends-Sections and Never-MarkAuto-Sections   /*{{{*/
  47 static bool
  48 ConfigValueInSubTree(const char* SubTree, const char *needle)
  49 {
  50    Configuration::Item const *Opts;
  51    Opts = _config->Tree(SubTree);
  52    if (Opts != 0 && Opts->Child != 0)
  53    {
  54       Opts = Opts->Child;
  55       for (; Opts != 0; Opts = Opts->Next)
  56       {
  57          if (Opts->Value.empty() == true)
  58             continue;
  59          if (strcmp(needle, Opts->Value.c_str()) == 0)
  60             return true;
  61       }
  62    }
  63    return false;
  64 }
  65                                                                         /*}}}*/
  66 pkgDepCache::ActionGroup::ActionGroup(pkgDepCache &cache) :             /*{{{*/
  67   d(NULL), cache(cache), released(false)
  68 {
  69   ++cache.group_level;
  70 }
  71
  72 void pkgDepCache::ActionGroup::release()
  73 {
  74   if(!released)
  75     {
  76       if(cache.group_level == 0)
  77         std::cerr << "W: Unbalanced action groups, expect badness" << std::endl;
  78       else
  79         {
  80           --cache.group_level;
  81
  82           if(cache.group_level == 0)
  83             cache.MarkAndSweep();
  84         }
  85
  86       released = true;
  87     }
  88 }
  89
  90 pkgDepCache::ActionGroup::~ActionGroup()
  91 {
  92   release();
  93 }
  94                                                                         /*}}}*/
  95 // DepCache::pkgDepCache - Constructors                                 /*{{{*/
  96 // ---------------------------------------------------------------------
  97 /* */
  98 pkgDepCache::pkgDepCache(pkgCache * const pCache,Policy * const Plcy) :
  99   group_level(0), Cache(pCache), PkgState(0), DepState(0),
 100    iUsrSize(0), iDownloadSize(0), iInstCount(0), iDelCount(0), iKeepCount(0),
 101    iBrokenCount(0), iPolicyBrokenCount(0), iBadCount(0), d(NULL)
 102 {
 103    DebugMarker = _config->FindB("Debug::pkgDepCache::Marker", false);
 104    DebugAutoInstall = _config->FindB("Debug::pkgDepCache::AutoInstall", false);
 105    delLocalPolicy = 0;
 106    LocalPolicy = Plcy;
 107    if (LocalPolicy == 0)
 108       delLocalPolicy = LocalPolicy = new Policy;
 109 }
 110                                                                         /*}}}*/
 111 // DepCache::~pkgDepCache - Destructor                                  /*{{{*/
 112 // ---------------------------------------------------------------------
 113 /* */
 114 pkgDepCache::~pkgDepCache()
 115 {
 116    delete [] PkgState;
 117    delete [] DepState;
 118    delete delLocalPolicy;
 119 }
 120                                                                         /*}}}*/
 121 // DepCache::Init - Generate the initial extra structures.              /*{{{*/
 122 // ---------------------------------------------------------------------
 123 /* This allocats the extension buffers and initializes them. */
 124 bool pkgDepCache::Init(OpProgress * const Prog)
 125 {
 126    // Suppress mark updates during this operation (just in case) and
 127    // run a mark operation when Init terminates.
 128    ActionGroup actions(*this);
 129
 130    delete [] PkgState;
 131    delete [] DepState;
 132    PkgState = new StateCache[Head().PackageCount];
 133    DepState = new unsigned char[Head().DependsCount];
 134    memset(PkgState,0,sizeof(*PkgState)*Head().PackageCount);
 135    memset(DepState,0,sizeof(*DepState)*Head().DependsCount);
 136
 137    if (Prog != 0)
 138    {
 139       Prog->OverallProgress(0,2*Head().PackageCount,Head().PackageCount,
 140                             _("Building dependency tree"));
 141       Prog->SubProgress(Head().PackageCount,_("Candidate versions"));
 142    }
 143
 144    /* Set the current state of everything. In this state all of the
 145       packages are kept exactly as is. See AllUpgrade */
 146    int Done = 0;
 147    for (PkgIterator I = PkgBegin(); I.end() != true; ++I, ++Done)
 148    {
 149       if (Prog != 0 && Done%20 == 0)
 150          Prog->Progress(Done);
 151
 152       // Find the proper cache slot
 153       StateCache &State = PkgState[I->ID];
 154       State.iFlags = 0;
 155
 156       // Figure out the install version
 157       State.CandidateVer = GetCandidateVer(I);
 158       State.InstallVer = I.CurrentVer();
 159       State.Mode = ModeKeep;
 160
 161       State.Update(I,*this);
 162    }
 163
 164    if (Prog != 0)
 165    {
 166       Prog->OverallProgress(Head().PackageCount,2*Head().PackageCount,
 167                             Head().PackageCount,
 168                             _("Building dependency tree"));
 169       Prog->SubProgress(Head().PackageCount,_("Dependency generation"));
 170    }
 171
 172    Update(Prog);
 173
 174    if(Prog != 0)
 175       Prog->Done();
 176
 177    return true;
 178 }
 179                                                                         /*}}}*/
 180 bool pkgDepCache::readStateFile(OpProgress * const Prog)                /*{{{*/
 181 {
 182    FileFd state_file;
 183    string const state = _config->FindFile("Dir::State::extended_states");
 184    if(RealFileExists(state)) {
 185       state_file.Open(state, FileFd::ReadOnly);
 186       off_t const file_size = state_file.Size();
 187       if(Prog != NULL)
 188          Prog->OverallProgress(0, file_size, 1,
 189                                _("Reading state information"));
 190
 191       pkgTagFile tagfile(&state_file);
 192       pkgTagSection section;
 193       off_t amt = 0;
 194       bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
 195       while(tagfile.Step(section)) {
 196          string const pkgname = section.FindS("Package");
 197          string pkgarch = section.FindS("Architecture");
 198          if (pkgarch.empty() == true)
 199             pkgarch = "any";
 200          pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
 201          // Silently ignore unknown packages and packages with no actual version.
 202          if(pkg.end() == true || pkg->VersionList == 0)
 203             continue;
 204
 205          short const reason = section.FindI("Auto-Installed", 0);
 206          if(reason > 0)
 207          {
 208             PkgState[pkg->ID].Flags |= Flag::Auto;
 209             if (unlikely(debug_autoremove))
 210                std::clog << "Auto-Installed : " << pkg.FullName() << std::endl;
 211             if (pkgarch == "any")
 212             {
 213                pkgCache::GrpIterator G = pkg.Group();
 214                for (pkg = G.NextPkg(pkg); pkg.end() != true; pkg = G.NextPkg(pkg))
 215                   if (pkg->VersionList != 0)
 216                      PkgState[pkg->ID].Flags |= Flag::Auto;
 217             }
 218          }
 219          amt += section.size();
 220          if(Prog != NULL)
 221             Prog->OverallProgress(amt, file_size, 1,
 222                                   _("Reading state information"));
 223       }
 224       if(Prog != NULL)
 225          Prog->OverallProgress(file_size, file_size, 1,
 226                                _("Reading state information"));
 227    }
 228
 229    return true;
 230 }
 231                                                                         /*}}}*/
 232 bool pkgDepCache::writeStateFile(OpProgress * const /*prog*/, bool const InstalledOnly) /*{{{*/
 233 {
 234    bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
 235
 236    if(debug_autoremove)
 237       std::clog << "pkgDepCache::writeStateFile()" << std::endl;
 238
 239    FileFd StateFile;
 240    string const state = _config->FindFile("Dir::State::extended_states");
 241    if (CreateAPTDirectoryIfNeeded(_config->FindDir("Dir::State"), flNotFile(state)) == false)
 242       return false;
 243
 244    // if it does not exist, create a empty one
 245    if(!RealFileExists(state))
 246    {
 247       StateFile.Open(state, FileFd::WriteAtomic);
 248       StateFile.Close();
 249    }
 250
 251    // open it
 252    if(!StateFile.Open(state, FileFd::ReadOnly))
 253       return _error->Error(_("Failed to open StateFile %s"),
 254                            state.c_str());
 255
 256    FileFd OutFile(state, FileFd::ReadWrite | FileFd::Atomic);
 257    if (OutFile.IsOpen() == false || OutFile.Failed() == true)
 258       return _error->Error(_("Failed to write temporary StateFile %s"), state.c_str());
 259
 260    // first merge with the existing sections
 261    pkgTagFile tagfile(&StateFile);
 262    pkgTagSection section;
 263    std::set<string> pkgs_seen;
 264    while(tagfile.Step(section)) {
 265          string const pkgname = section.FindS("Package");
 266          string pkgarch = section.FindS("Architecture");
 267          if (pkgarch.empty() == true)
 268             pkgarch = "native";
 269          // Silently ignore unknown packages and packages with no actual
 270          // version.
 271          pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
 272          if(pkg.end() || pkg.VersionList().end())
 273             continue;
 274          StateCache const &P = PkgState[pkg->ID];
 275          bool newAuto = (P.Flags & Flag::Auto);
 276          // skip not installed or now-removed ones if requested
 277          if (InstalledOnly && (
 278              (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
 279              (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
 280          {
 281             // The section is obsolete if it contains no other tag
 282             unsigned int const count = section.Count();
 283             if (count < 2 ||
 284                 (count == 2 && section.Exists("Auto-Installed")) ||
 285                 (count == 3 && section.Exists("Auto-Installed") && section.Exists("Architecture")))
 286                continue;
 287             else
 288                newAuto = false;
 289          }
 290          if(_config->FindB("Debug::pkgAutoRemove",false))
 291             std::clog << "Update existing AutoInstall info: "
 292                       << pkg.FullName() << std::endl;
 293
 294          std::vector<pkgTagSection::Tag> rewrite;
 295          rewrite.push_back(pkgTagSection::Tag::Rewrite("Architecture", pkg.Arch()));
 296          rewrite.push_back(pkgTagSection::Tag::Rewrite("Auto-Installed", newAuto ? "1" : "0"));
 297          section.Write(OutFile, NULL, rewrite);
 298          if (OutFile.Write("\n", 1) == false)
 299             return false;
 300          pkgs_seen.insert(pkg.FullName());
 301    }
 302
 303    // then write the ones we have not seen yet
 304    for(pkgCache::PkgIterator pkg=Cache->PkgBegin(); !pkg.end(); ++pkg) {
 305       StateCache const &P = PkgState[pkg->ID];
 306       if(P.Flags & Flag::Auto) {
 307          if (pkgs_seen.find(pkg.FullName()) != pkgs_seen.end()) {
 308             if(debug_autoremove)
 309                std::clog << "Skipping already written " << pkg.FullName() << std::endl;
 310             continue;
 311          }
 312          // skip not installed ones if requested
 313          if (InstalledOnly && (
 314              (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
 315              (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
 316             continue;
 317          const char* const pkgarch = pkg.Arch();
 318          if (strcmp(pkgarch, "all") == 0)
 319             continue;
 320          if(debug_autoremove)
 321             std::clog << "Writing new AutoInstall: " << pkg.FullName() << std::endl;
 322          std::string stanza = "Package: ";
 323          stanza.append(pkg.Name())
 324               .append("\nArchitecture: ").append(pkgarch)
 325               .append("\nAuto-Installed: 1\n\n");
 326          if (OutFile.Write(stanza.c_str(), stanza.length()) == false)
 327             return false;
 328       }
 329    }
 330    if (OutFile.Close() == false)
 331       return false;
 332    chmod(state.c_str(), 0644);
 333    return true;
 334 }
 335                                                                         /*}}}*/
 336 // DepCache::CheckDep - Checks a single dependency                      /*{{{*/
 337 // ---------------------------------------------------------------------
 338 /* This first checks the dependency against the main target package and
 339    then walks along the package provides list and checks if each provides
 340    will be installed then checks the provides against the dep. Res will be
 341    set to the package which was used to satisfy the dep. */
 342 bool pkgDepCache::CheckDep(DepIterator const &Dep,int const Type,PkgIterator &Res)
 343 {
 344    Res = Dep.TargetPkg();
 345
 346    /* Check simple depends. A depends -should- never self match but
 347       we allow it anyhow because dpkg does. Technically it is a packaging
 348       bug. Conflicts may never self match */
 349    if (Dep.IsIgnorable(Res) == false)
 350    {
 351       // Check the base package
 352       if (Type == NowVersion)
 353       {
 354          if (Res->CurrentVer != 0 && Dep.IsSatisfied(Res.CurrentVer()) == true)
 355             return true;
 356       }
 357       else if (Type == InstallVersion)
 358       {
 359          if (PkgState[Res->ID].InstallVer != 0 &&
 360                Dep.IsSatisfied(PkgState[Res->ID].InstVerIter(*this)) == true)
 361             return true;
 362       }
 363       else if (Type == CandidateVersion)
 364          if (PkgState[Res->ID].CandidateVer != 0 &&
 365                Dep.IsSatisfied(PkgState[Res->ID].CandidateVerIter(*this)) == true)
 366             return true;
 367    }
 368
 369    if (Dep->Type == Dep::Obsoletes)
 370       return false;
 371
 372    // Check the providing packages
 373    PrvIterator P = Dep.TargetPkg().ProvidesList();
 374    for (; P.end() != true; ++P)
 375    {
 376       if (Dep.IsIgnorable(P) == true)
 377          continue;
 378
 379       // Check if the provides is a hit
 380       if (Type == NowVersion)
 381       {
 382          if (P.OwnerPkg().CurrentVer() != P.OwnerVer())
 383             continue;
 384       }
 385       else if (Type == InstallVersion)
 386       {
 387          StateCache &State = PkgState[P.OwnerPkg()->ID];
 388          if (State.InstallVer != (Version *)P.OwnerVer())
 389             continue;
 390       }
 391       else if (Type == CandidateVersion)
 392       {
 393          StateCache &State = PkgState[P.OwnerPkg()->ID];
 394          if (State.CandidateVer != (Version *)P.OwnerVer())
 395             continue;
 396       }
 397
 398       // Compare the versions.
 399       if (Dep.IsSatisfied(P) == true)
 400       {
 401          Res = P.OwnerPkg();
 402          return true;
 403       }
 404    }
 405
 406    return false;
 407 }
 408                                                                         /*}}}*/
 409 // DepCache::AddSizes - Add the packages sizes to the counters          /*{{{*/
 410 // ---------------------------------------------------------------------
 411 /* Call with Inverse = true to preform the inverse opration */
 412 void pkgDepCache::AddSizes(const PkgIterator &Pkg, bool const Inverse)
 413 {
 414    StateCache &P = PkgState[Pkg->ID];
 415
 416    if (Pkg->VersionList == 0)
 417       return;
 418
 419    if (Pkg.State() == pkgCache::PkgIterator::NeedsConfigure &&
 420        P.Keep() == true)
 421       return;
 422
 423    // Compute the size data
 424    if (P.NewInstall() == true)
 425    {
 426       if (Inverse == false) {
 427          iUsrSize += P.InstVerIter(*this)->InstalledSize;
 428          iDownloadSize += P.InstVerIter(*this)->Size;
 429       } else {
 430          iUsrSize -= P.InstVerIter(*this)->InstalledSize;
 431          iDownloadSize -= P.InstVerIter(*this)->Size;
 432       }
 433       return;
 434    }
 435
 436    // Upgrading
 437    if (Pkg->CurrentVer != 0 &&
 438        (P.InstallVer != (Version *)Pkg.CurrentVer() ||
 439         (P.iFlags & ReInstall) == ReInstall) && P.InstallVer != 0)
 440    {
 441       if (Inverse == false) {
 442          iUsrSize -= Pkg.CurrentVer()->InstalledSize;
 443          iUsrSize += P.InstVerIter(*this)->InstalledSize;
 444          iDownloadSize += P.InstVerIter(*this)->Size;
 445       } else {
 446          iUsrSize -= P.InstVerIter(*this)->InstalledSize;
 447          iUsrSize += Pkg.CurrentVer()->InstalledSize;
 448          iDownloadSize -= P.InstVerIter(*this)->Size;
 449       }
 450       return;
 451    }
 452
 453    // Reinstall
 454    if (Pkg.State() == pkgCache::PkgIterator::NeedsUnpack &&
 455        P.Delete() == false)
 456    {
 457       if (Inverse == false)
 458          iDownloadSize += P.InstVerIter(*this)->Size;
 459       else
 460          iDownloadSize -= P.InstVerIter(*this)->Size;
 461       return;
 462    }
 463
 464    // Removing
 465    if (Pkg->CurrentVer != 0 && P.InstallVer == 0)
 466    {
 467       if (Inverse == false)
 468          iUsrSize -= Pkg.CurrentVer()->InstalledSize;
 469       else
 470          iUsrSize += Pkg.CurrentVer()->InstalledSize;
 471       return;
 472    }
 473 }
 474                                                                         /*}}}*/
 475 // DepCache::AddStates - Add the package to the state counter           /*{{{*/
 476 // ---------------------------------------------------------------------
 477 /* This routine is tricky to use, you must make sure that it is never
 478    called twice for the same package. This means the Remove/Add section
 479    should be as short as possible and not encompass any code that will
 480    calld Remove/Add itself. Remember, dependencies can be circular so
 481    while processing a dep for Pkg it is possible that Add/Remove
 482    will be called on Pkg */
 483 void pkgDepCache::AddStates(const PkgIterator &Pkg, bool const Invert)
 484 {
 485    signed char const Add = (Invert == false) ? 1 : -1;
 486    StateCache &State = PkgState[Pkg->ID];
 487
 488    // The Package is broken (either minimal dep or policy dep)
 489    if ((State.DepState & DepInstMin) != DepInstMin)
 490       iBrokenCount += Add;
 491    if ((State.DepState & DepInstPolicy) != DepInstPolicy)
 492       iPolicyBrokenCount += Add;
 493
 494    // Bad state
 495    if (Pkg.State() != PkgIterator::NeedsNothing)
 496       iBadCount += Add;
 497
 498    // Not installed
 499    if (Pkg->CurrentVer == 0)
 500    {
 501       if (State.Mode == ModeDelete &&
 502           (State.iFlags & Purge) == Purge && Pkg.Purge() == false)
 503          iDelCount += Add;
 504
 505       if (State.Mode == ModeInstall)
 506          iInstCount += Add;
 507       return;
 508    }
 509
 510    // Installed, no upgrade
 511    if (State.Status == 0)
 512    {
 513       if (State.Mode == ModeDelete)
 514          iDelCount += Add;
 515       else
 516          if ((State.iFlags & ReInstall) == ReInstall)
 517             iInstCount += Add;
 518       return;
 519    }
 520
 521    // Alll 3 are possible
 522    if (State.Mode == ModeDelete)
 523       iDelCount += Add;
 524    else if (State.Mode == ModeKeep)
 525       iKeepCount += Add;
 526    else if (State.Mode == ModeInstall)
 527       iInstCount += Add;
 528 }
 529                                                                         /*}}}*/
 530 // DepCache::BuildGroupOrs - Generate the Or group dep data             /*{{{*/
 531 // ---------------------------------------------------------------------
 532 /* The or group results are stored in the last item of the or group. This
 533    allows easy detection of the state of a whole or'd group. */
 534 void pkgDepCache::BuildGroupOrs(VerIterator const &V)
 535 {
 536    unsigned char Group = 0;
 537    for (DepIterator D = V.DependsList(); D.end() != true; ++D)
 538    {
 539       // Build the dependency state.
 540       unsigned char &State = DepState[D->ID];
 541
 542       /* Invert for Conflicts. We have to do this twice to get the
 543          right sense for a conflicts group */
 544       if (D.IsNegative() == true)
 545          State = ~State;
 546
 547       // Add to the group if we are within an or..
 548       State &= 0x7;
 549       Group |= State;
 550       State |= Group << 3;
 551       if ((D->CompareOp & Dep::Or) != Dep::Or)
 552          Group = 0;
 553
 554       // Invert for Conflicts
 555       if (D.IsNegative() == true)
 556          State = ~State;
 557    }
 558 }
 559                                                                         /*}}}*/
 560 // DepCache::VersionState - Perform a pass over a dependency list       /*{{{*/
 561 // ---------------------------------------------------------------------
 562 /* This is used to run over a dependency list and determine the dep
 563    state of the list, filtering it through both a Min check and a Policy
 564    check. The return result will have SetMin/SetPolicy low if a check
 565    fails. It uses the DepState cache for it's computations. */
 566 unsigned char pkgDepCache::VersionState(DepIterator D, unsigned char const Check,
 567                                        unsigned char const SetMin,
 568                                        unsigned char const SetPolicy) const
 569 {
 570    unsigned char Dep = 0xFF;
 571    while (D.end() != true)
 572    {
 573       // the last or-dependency has the state of all previous or'ed
 574       DepIterator Start, End;
 575       D.GlobOr(Start, End);
 576       // ignore if we are called with Dep{Install,…} or DepG{Install,…}
 577       // the later would be more correct, but the first is what we get
 578       unsigned char const State = DepState[End->ID] | (DepState[End->ID] >> 3);
 579
 580       // Minimum deps that must be satisfied to have a working package
 581       if (Start.IsCritical() == true)
 582       {
 583          if ((State & Check) != Check)
 584             return Dep &= ~(SetMin | SetPolicy);
 585       }
 586       // Policy deps that must be satisfied to install the package
 587       else if (IsImportantDep(Start) == true &&
 588           (State & Check) != Check)
 589          Dep &= ~SetPolicy;
 590    }
 591    return Dep;
 592 }
 593                                                                         /*}}}*/
 594 // DepCache::DependencyState - Compute the 3 results for a dep          /*{{{*/
 595 // ---------------------------------------------------------------------
 596 /* This is the main dependency computation bit. It computes the 3 main
 597    results for a dependencys, Now, Install and Candidate. Callers must
 598    invert the result if dealing with conflicts. */
 599 unsigned char pkgDepCache::DependencyState(DepIterator const &D)
 600 {
 601    unsigned char State = 0;
 602
 603    if (CheckDep(D,NowVersion) == true)
 604       State |= DepNow;
 605    if (CheckDep(D,InstallVersion) == true)
 606       State |= DepInstall;
 607    if (CheckDep(D,CandidateVersion) == true)
 608       State |= DepCVer;
 609
 610    return State;
 611 }
 612                                                                         /*}}}*/
 613 // DepCache::UpdateVerState - Compute the Dep member of the state       /*{{{*/
 614 // ---------------------------------------------------------------------
 615 /* This determines the combined dependency representation of a package
 616    for its two states now and install. This is done by using the pre-generated
 617    dependency information. */
 618 void pkgDepCache::UpdateVerState(PkgIterator const &Pkg)
 619 {
 620    // Empty deps are always true
 621    StateCache &State = PkgState[Pkg->ID];
 622    State.DepState = 0xFF;
 623
 624    // Check the Current state
 625    if (Pkg->CurrentVer != 0)
 626    {
 627       DepIterator D = Pkg.CurrentVer().DependsList();
 628       State.DepState &= VersionState(D,DepNow,DepNowMin,DepNowPolicy);
 629    }
 630
 631    /* Check the candidate state. We do not compare against the whole as
 632       a candidate state but check the candidate version against the
 633       install states */
 634    if (State.CandidateVer != 0)
 635    {
 636       DepIterator D = State.CandidateVerIter(*this).DependsList();
 637       State.DepState &= VersionState(D,DepInstall,DepCandMin,DepCandPolicy);
 638    }
 639
 640    // Check target state which can only be current or installed
 641    if (State.InstallVer != 0)
 642    {
 643       DepIterator D = State.InstVerIter(*this).DependsList();
 644       State.DepState &= VersionState(D,DepInstall,DepInstMin,DepInstPolicy);
 645    }
 646 }
 647                                                                         /*}}}*/
 648 // DepCache::Update - Figure out all the state information              /*{{{*/
 649 // ---------------------------------------------------------------------
 650 /* This will figure out the state of all the packages and all the
 651    dependencies based on the current policy. */
 652 void pkgDepCache::Update(OpProgress * const Prog)
 653 {
 654    iUsrSize = 0;
 655    iDownloadSize = 0;
 656    iInstCount = 0;
 657    iDelCount = 0;
 658    iKeepCount = 0;
 659    iBrokenCount = 0;
 660    iPolicyBrokenCount = 0;
 661    iBadCount = 0;
 662
 663    // Perform the depends pass
 664    int Done = 0;
 665    for (PkgIterator I = PkgBegin(); I.end() != true; ++I, ++Done)
 666    {
 667       if (Prog != 0 && Done%20 == 0)
 668          Prog->Progress(Done);
 669       for (VerIterator V = I.VersionList(); V.end() != true; ++V)
 670       {
 671          unsigned char Group = 0;
 672
 673          for (DepIterator D = V.DependsList(); D.end() != true; ++D)
 674          {
 675             // Build the dependency state.
 676             unsigned char &State = DepState[D->ID];
 677             State = DependencyState(D);
 678
 679             // Add to the group if we are within an or..
 680             Group |= State;
 681             State |= Group << 3;
 682             if ((D->CompareOp & Dep::Or) != Dep::Or)
 683                Group = 0;
 684
 685             // Invert for Conflicts
 686             if (D.IsNegative() == true)
 687                State = ~State;
 688          }
 689       }
 690
 691       // Compute the package dependency state and size additions
 692       AddSizes(I);
 693       UpdateVerState(I);
 694       AddStates(I);
 695    }
 696
 697    if (Prog != 0)
 698       Prog->Progress(Done);
 699
 700    readStateFile(Prog);
 701 }
 702                                                                         /*}}}*/
 703 // DepCache::Update - Update the deps list of a package                 /*{{{*/
 704 // ---------------------------------------------------------------------
 705 /* This is a helper for update that only does the dep portion of the scan.
 706    It is mainly meant to scan reverse dependencies. */
 707 void pkgDepCache::Update(DepIterator D)
 708 {
 709    // Update the reverse deps
 710    for (;D.end() != true; ++D)
 711    {
 712       unsigned char &State = DepState[D->ID];
 713       State = DependencyState(D);
 714
 715       // Invert for Conflicts
 716       if (D.IsNegative() == true)
 717          State = ~State;
 718
 719       RemoveStates(D.ParentPkg());
 720       BuildGroupOrs(D.ParentVer());
 721       UpdateVerState(D.ParentPkg());
 722       AddStates(D.ParentPkg());
 723    }
 724 }
 725                                                                         /*}}}*/
 726 // DepCache::Update - Update the related deps of a package              /*{{{*/
 727 // ---------------------------------------------------------------------
 728 /* This is called whenever the state of a package changes. It updates
 729    all cached dependencies related to this package. */
 730 void pkgDepCache::Update(PkgIterator const &Pkg)
 731 {
 732    // Recompute the dep of the package
 733    RemoveStates(Pkg);
 734    UpdateVerState(Pkg);
 735    AddStates(Pkg);
 736
 737    // Update the reverse deps
 738    Update(Pkg.RevDependsList());
 739
 740    // Update the provides map for the current ver
 741    if (Pkg->CurrentVer != 0)
 742       for (PrvIterator P = Pkg.CurrentVer().ProvidesList();
 743            P.end() != true; ++P)
 744          Update(P.ParentPkg().RevDependsList());
 745
 746    // Update the provides map for the candidate ver
 747    if (PkgState[Pkg->ID].CandidateVer != 0)
 748       for (PrvIterator P = PkgState[Pkg->ID].CandidateVerIter(*this).ProvidesList();
 749            P.end() != true; ++P)
 750          Update(P.ParentPkg().RevDependsList());
 751 }
 752                                                                         /*}}}*/
 753 // DepCache::MarkKeep - Put the package in the keep state               /*{{{*/
 754 // ---------------------------------------------------------------------
 755 /* */
 756 bool pkgDepCache::MarkKeep(PkgIterator const &Pkg, bool Soft, bool FromUser,
 757                            unsigned long Depth)
 758 {
 759    if (IsModeChangeOk(ModeKeep, Pkg, Depth, FromUser) == false)
 760       return false;
 761
 762    /* Reject an attempt to keep a non-source broken installed package, those
 763       must be upgraded */
 764    if (Pkg.State() == PkgIterator::NeedsUnpack &&
 765        Pkg.CurrentVer().Downloadable() == false)
 766       return false;
 767
 768    /* We changed the soft state all the time so the UI is a bit nicer
 769       to use */
 770    StateCache &P = PkgState[Pkg->ID];
 771
 772    // Check that it is not already kept
 773    if (P.Mode == ModeKeep)
 774       return true;
 775
 776    if (Soft == true)
 777       P.iFlags |= AutoKept;
 778    else
 779       P.iFlags &= ~AutoKept;
 780
 781    ActionGroup group(*this);
 782
 783 #if 0 // reseting the autoflag here means we lose the
 784       // auto-mark information if a user selects a package for removal
 785       // but changes  his mind then and sets it for keep again
 786       // - this makes sense as default when all Garbage dependencies
 787       //   are automatically marked for removal (as aptitude does).
 788       //   setting a package for keep then makes it no longer autoinstalled
 789       //   for all other use-case this action is rather surprising
 790    if(FromUser && !P.Marked)
 791      P.Flags &= ~Flag::Auto;
 792 #endif
 793
 794    if (DebugMarker == true)
 795       std::clog << OutputInDepth(Depth) << "MarkKeep " << Pkg << " FU=" << FromUser << std::endl;
 796
 797    RemoveSizes(Pkg);
 798    RemoveStates(Pkg);
 799
 800    P.Mode = ModeKeep;
 801    if (Pkg->CurrentVer == 0)
 802       P.InstallVer = 0;
 803    else
 804       P.InstallVer = Pkg.CurrentVer();
 805
 806    AddStates(Pkg);
 807    Update(Pkg);
 808    AddSizes(Pkg);
 809
 810    return true;
 811 }
 812                                                                         /*}}}*/
 813 // DepCache::MarkDelete - Put the package in the delete state           /*{{{*/
 814 // ---------------------------------------------------------------------
 815 /* */
 816 bool pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge,
 817                              unsigned long Depth, bool FromUser)
 818 {
 819    if (IsModeChangeOk(ModeDelete, Pkg, Depth, FromUser) == false)
 820       return false;
 821
 822    StateCache &P = PkgState[Pkg->ID];
 823
 824    // Check that it is not already marked for delete
 825    if ((P.Mode == ModeDelete || P.InstallVer == 0) &&
 826        (Pkg.Purge() == true || rPurge == false))
 827       return true;
 828
 829    // check if we are allowed to remove the package
 830    if (IsDeleteOk(Pkg,rPurge,Depth,FromUser) == false)
 831       return false;
 832
 833    P.iFlags &= ~(AutoKept | Purge);
 834    if (rPurge == true)
 835       P.iFlags |= Purge;
 836
 837    ActionGroup group(*this);
 838
 839    if (FromUser == false)
 840    {
 841       VerIterator const PV = P.InstVerIter(*this);
 842       if (PV.end() == false)
 843       {
 844          // removed metapackages mark their dependencies as manual to prevent in "desktop depends browser, texteditor"
 845          // the removal of browser to suggest the removal of desktop and texteditor.
 846          // We ignore the auto-bit here as we can't deal with metapackage cascardes otherwise.
 847          // We do not check for or-groups here as we don't know which package takes care of
 848          // providing the feature the user likes e.g.:  browser1 | browser2 | browser3
 849          // Temporary removals are effected by this as well, which is bad, but unlikely in practice
 850          bool const PinNeverMarkAutoSection = (PV->Section != 0 && ConfigValueInSubTree("APT::Never-MarkAuto-Sections", PV.Section()));
 851          if (PinNeverMarkAutoSection)
 852          {
 853             for (DepIterator D = PV.DependsList(); D.end() != true; ++D)
 854             {
 855                if (D.IsMultiArchImplicit() == true || D.IsNegative() == true || IsImportantDep(D) == false)
 856                   continue;
 857
 858                pkgCacheFile CacheFile(this);
 859                APT::VersionList verlist = APT::VersionList::FromDependency(CacheFile, D, APT::CacheSetHelper::INSTALLED);
 860                for (auto const &V : verlist)
 861                {
 862                   PkgIterator const DP = V.ParentPkg();
 863                   if(DebugAutoInstall == true)
 864                      std::clog << OutputInDepth(Depth) << "Setting " << DP.FullName(false) << " NOT as auto-installed (direct "
 865                         << D.DepType() << " of " << Pkg.FullName(false) << " which is in APT::Never-MarkAuto-Sections)" << std::endl;
 866
 867                   MarkAuto(DP, false);
 868                }
 869             }
 870          }
 871       }
 872    }
 873
 874    if (DebugMarker == true)
 875       std::clog << OutputInDepth(Depth) << (rPurge ? "MarkPurge " : "MarkDelete ") << Pkg << " FU=" << FromUser << std::endl;
 876
 877    RemoveSizes(Pkg);
 878    RemoveStates(Pkg);
 879
 880    if (Pkg->CurrentVer == 0 && (Pkg.Purge() == true || rPurge == false))
 881       P.Mode = ModeKeep;
 882    else
 883       P.Mode = ModeDelete;
 884    P.InstallVer = 0;
 885
 886    AddStates(Pkg);
 887    Update(Pkg);
 888    AddSizes(Pkg);
 889
 890    return true;
 891 }
 892                                                                         /*}}}*/
 893 // DepCache::IsDeleteOk - check if it is ok to remove this package      /*{{{*/
 894 // ---------------------------------------------------------------------
 895 /* The default implementation tries to prevent deletion of install requests.
 896    dpkg holds are enforced by the private IsModeChangeOk */
 897 bool pkgDepCache::IsDeleteOk(PkgIterator const &Pkg,bool rPurge,
 898                               unsigned long Depth, bool FromUser)
 899 {
 900    return IsDeleteOkProtectInstallRequests(Pkg, rPurge, Depth, FromUser);
 901 }
 902 bool pkgDepCache::IsDeleteOkProtectInstallRequests(PkgIterator const &Pkg,
 903       bool const /*rPurge*/, unsigned long const Depth, bool const FromUser)
 904 {
 905    if (FromUser == false && Pkg->CurrentVer == 0)
 906    {
 907       StateCache &P = PkgState[Pkg->ID];
 908       if (P.InstallVer != 0 && P.Status == 2 && (P.Flags & Flag::Auto) != Flag::Auto)
 909       {
 910          if (DebugMarker == true)
 911             std::clog << OutputInDepth(Depth) << "Manual install request prevents MarkDelete of " << Pkg << std::endl;
 912          return false;
 913       }
 914    }
 915    return true;
 916 }
 917                                                                         /*}}}*/
 918 // DepCache::IsModeChangeOk - check if it is ok to change the mode      /*{{{*/
 919 // ---------------------------------------------------------------------
 920 /* this is used by all Mark methods on the very first line to check sanity
 921    and prevents mode changes for packages on hold for example.
 922    If you want to check Mode specific stuff you can use the virtual public
 923    Is<Mode>Ok methods instead */
 924 static char const* PrintMode(char const mode)
 925 {
 926          switch (mode)
 927          {
 928          case pkgDepCache::ModeInstall: return "Install";
 929          case pkgDepCache::ModeKeep: return "Keep";
 930          case pkgDepCache::ModeDelete: return "Delete";
 931          case pkgDepCache::ModeGarbage: return "Garbage";
 932          default: return "UNKNOWN";
 933          }
 934 }
 935 bool pkgDepCache::IsModeChangeOk(ModeList const mode, PkgIterator const &Pkg,
 936                                  unsigned long const Depth, bool const FromUser)
 937 {
 938    // we are not trying to hard…
 939    if (unlikely(Depth > 100))
 940       return false;
 941
 942    // general sanity
 943    if (unlikely(Pkg.end() == true || Pkg->VersionList == 0))
 944       return false;
 945
 946    // the user is always right
 947    if (FromUser == true)
 948       return true;
 949
 950    StateCache &P = PkgState[Pkg->ID];
 951    // not changing the mode is obviously also fine as we might want to call
 952    // e.g. MarkInstall multiple times with different arguments for the same package
 953    if (P.Mode == mode)
 954       return true;
 955
 956    // if previous state was set by user only user can reset it
 957    if ((P.iFlags & Protected) == Protected)
 958    {
 959       if (unlikely(DebugMarker == true))
 960          std::clog << OutputInDepth(Depth) << "Ignore Mark" << PrintMode(mode)
 961                    << " of " << Pkg << " as its mode (" << PrintMode(P.Mode)
 962                    << ") is protected" << std::endl;
 963       return false;
 964    }
 965    // enforce dpkg holds
 966    else if (mode != ModeKeep && Pkg->SelectedState == pkgCache::State::Hold &&
 967             _config->FindB("APT::Ignore-Hold",false) == false)
 968    {
 969       if (unlikely(DebugMarker == true))
 970          std::clog << OutputInDepth(Depth) << "Hold prevents Mark" << PrintMode(mode)
 971                    << " of " << Pkg << std::endl;
 972       return false;
 973    }
 974
 975    return true;
 976 }
 977                                                                         /*}}}*/
 978 // DepCache::MarkInstall - Put the package in the install state         /*{{{*/
 979 // ---------------------------------------------------------------------
 980 /* */
 981 struct CompareProviders {
 982    pkgCache::PkgIterator const Pkg;
 983    explicit CompareProviders(pkgCache::DepIterator const &Dep) : Pkg(Dep.TargetPkg()) {};
 984    //bool operator() (APT::VersionList::iterator const &AV, APT::VersionList::iterator const &BV)
 985    bool operator() (pkgCache::VerIterator const &AV, pkgCache::VerIterator const &BV)
 986    {
 987       pkgCache::PkgIterator const A = AV.ParentPkg();
 988       pkgCache::PkgIterator const B = BV.ParentPkg();
 989       // Prefer MA:same packages if other architectures for it are installed
 990       if ((AV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same ||
 991           (BV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
 992       {
 993          bool instA = false;
 994          if ((AV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
 995          {
 996             pkgCache::GrpIterator Grp = A.Group();
 997             for (pkgCache::PkgIterator P = Grp.PackageList(); P.end() == false; P = Grp.NextPkg(P))
 998                if (P->CurrentVer != 0)
 999                {
1000                   instA = true;
1001                   break;
1002                }
1003          }
1004          bool instB = false;
1005          if ((BV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
1006          {
1007             pkgCache::GrpIterator Grp = B.Group();
1008             for (pkgCache::PkgIterator P = Grp.PackageList(); P.end() == false; P = Grp.NextPkg(P))
1009             {
1010                if (P->CurrentVer != 0)
1011                {
1012                   instB = true;
1013                   break;
1014                }
1015             }
1016          }
1017          if (instA != instB)
1018             return instA == false;
1019       }
1020       // Prefer packages in the same group as the target; e.g. foo:i386, foo:amd64
1021       if (A->Group != B->Group)
1022       {
1023          if (A->Group == Pkg->Group && B->Group != Pkg->Group)
1024             return false;
1025          else if (B->Group == Pkg->Group && A->Group != Pkg->Group)
1026             return true;
1027       }
1028       // we like essentials
1029       if ((A->Flags & pkgCache::Flag::Essential) != (B->Flags & pkgCache::Flag::Essential))
1030       {
1031          if ((A->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
1032             return false;
1033          else if ((B->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
1034             return true;
1035       }
1036       if ((A->Flags & pkgCache::Flag::Important) != (B->Flags & pkgCache::Flag::Important))
1037       {
1038          if ((A->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important)
1039             return false;
1040          else if ((B->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important)
1041             return true;
1042       }
1043       // prefer native architecture
1044       if (strcmp(A.Arch(), B.Arch()) != 0)
1045       {
1046          if (strcmp(A.Arch(), A.Cache()->NativeArch()) == 0)
1047             return false;
1048          else if (strcmp(B.Arch(), B.Cache()->NativeArch()) == 0)
1049             return true;
1050          std::vector<std::string> archs = APT::Configuration::getArchitectures();
1051          for (std::vector<std::string>::const_iterator a = archs.begin(); a != archs.end(); ++a)
1052             if (*a == A.Arch())
1053                return false;
1054             else if (*a == B.Arch())
1055                return true;
1056       }
1057       // higher priority seems like a good idea
1058       if (AV->Priority != BV->Priority)
1059          return AV->Priority > BV->Priority;
1060       // unable to decide…
1061       return A->ID < B->ID;
1062    }
1063 };
1064 bool pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
1065                               unsigned long Depth, bool FromUser,
1066                               bool ForceImportantDeps)
1067 {
1068    if (IsModeChangeOk(ModeInstall, Pkg, Depth, FromUser) == false)
1069       return false;
1070
1071    StateCache &P = PkgState[Pkg->ID];
1072
1073    // See if there is even any possible instalation candidate
1074    if (P.CandidateVer == 0)
1075       return false;
1076
1077    /* Check that it is not already marked for install and that it can be
1078       installed */
1079    if ((P.InstPolicyBroken() == false && P.InstBroken() == false) &&
1080        (P.Mode == ModeInstall ||
1081         P.CandidateVer == (Version *)Pkg.CurrentVer()))
1082    {
1083       if (P.CandidateVer == (Version *)Pkg.CurrentVer() && P.InstallVer == 0)
1084          return MarkKeep(Pkg, false, FromUser, Depth+1);
1085       return true;
1086    }
1087
1088    // check if we are allowed to install the package
1089    if (IsInstallOk(Pkg,AutoInst,Depth,FromUser) == false)
1090       return false;
1091
1092    ActionGroup group(*this);
1093    P.iFlags &= ~AutoKept;
1094
1095    /* Target the candidate version and remove the autoflag. We reset the
1096       autoflag below if this was called recursively. Otherwise the user
1097       should have the ability to de-auto a package by changing its state */
1098    RemoveSizes(Pkg);
1099    RemoveStates(Pkg);
1100
1101    P.Mode = ModeInstall;
1102    P.InstallVer = P.CandidateVer;
1103
1104    if(FromUser)
1105      {
1106        // Set it to manual if it's a new install or already installed,
1107        // but only if its not marked by the autoremover (aptitude depend on this behavior)
1108        // or if we do automatic installation (aptitude never does it)
1109        if(P.Status == 2 || (Pkg->CurrentVer != 0 && (AutoInst == true || P.Marked == false)))
1110          P.Flags &= ~Flag::Auto;
1111      }
1112    else
1113      {
1114        // Set it to auto if this is a new install.
1115        if(P.Status == 2)
1116          P.Flags |= Flag::Auto;
1117      }
1118    if (P.CandidateVer == (Version *)Pkg.CurrentVer())
1119       P.Mode = ModeKeep;
1120
1121    AddStates(Pkg);
1122    Update(Pkg);
1123    AddSizes(Pkg);
1124
1125    if (AutoInst == false || _config->Find("APT::Solver", "internal") != "internal")
1126       return true;
1127
1128    if (DebugMarker == true)
1129       std::clog << OutputInDepth(Depth) << "MarkInstall " << Pkg << " FU=" << FromUser << std::endl;
1130
1131    VerIterator const PV = P.InstVerIter(*this);
1132    if (unlikely(PV.end() == true))
1133       return false;
1134
1135    DepIterator Dep = PV.DependsList();
1136    for (; Dep.end() != true;)
1137    {
1138       // Grok or groups
1139       DepIterator Start = Dep;
1140       bool Result = true;
1141       unsigned Ors = 0;
1142       for (bool LastOR = true; Dep.end() == false && LastOR == true; ++Dep, ++Ors)
1143       {
1144          LastOR = (Dep->CompareOp & Dep::Or) == Dep::Or;
1145
1146          if ((DepState[Dep->ID] & DepInstall) == DepInstall)
1147             Result = false;
1148       }
1149
1150       // Dep is satisfied okay.
1151       if (Result == false)
1152          continue;
1153
1154       /* Check if this dep should be consider for install. If it is a user
1155          defined important dep and we are installed a new package then
1156          it will be installed. Otherwise we only check for important
1157          deps that have changed from the installed version */
1158       if (IsImportantDep(Start) == false)
1159          continue;
1160
1161       /* If we are in an or group locate the first or that can
1162          succeed. We have already cached this… */
1163       for (; Ors > 1 && (DepState[Start->ID] & DepCVer) != DepCVer; --Ors)
1164          ++Start;
1165
1166       /* unsatisfiable dependency: IsInstallOkDependenciesSatisfiableByCandidates
1167          would have prevented us to get here if not overridden, so just skip
1168          over the problem here as the frontend will know what it is doing */
1169       if (Ors == 1 && (DepState[Start->ID] &DepCVer) != DepCVer && Start.IsNegative() == false)
1170          continue;
1171
1172       /* Check if any ImportantDep() (but not Critical) were added
1173        * since we installed the package.  Also check for deps that
1174        * were satisfied in the past: for instance, if a version
1175        * restriction in a Recommends was tightened, upgrading the
1176        * package should follow that Recommends rather than causing the
1177        * dependency to be removed. (bug #470115)
1178        */
1179       if (Pkg->CurrentVer != 0 && ForceImportantDeps == false && Start.IsCritical() == false)
1180       {
1181          bool isNewImportantDep = true;
1182          bool isPreviouslySatisfiedImportantDep = false;
1183          for (DepIterator D = Pkg.CurrentVer().DependsList(); D.end() != true; ++D)
1184          {
1185             //FIXME: Should we handle or-group better here?
1186             // We do not check if the package we look for is part of the same or-group
1187             // we might find while searching, but could that really be a problem?
1188             if (D.IsCritical() == true || IsImportantDep(D) == false ||
1189                 Start.TargetPkg() != D.TargetPkg())
1190                continue;
1191
1192             isNewImportantDep = false;
1193
1194             while ((D->CompareOp & Dep::Or) != 0)
1195                ++D;
1196
1197             isPreviouslySatisfiedImportantDep = (((*this)[D] & DepGNow) != 0);
1198             if (isPreviouslySatisfiedImportantDep == true)
1199                break;
1200          }
1201
1202          if(isNewImportantDep == true)
1203          {
1204             if (DebugAutoInstall == true)
1205                std::clog << OutputInDepth(Depth) << "new important dependency: "
1206                          << Start.TargetPkg().FullName() << std::endl;
1207          }
1208          else if(isPreviouslySatisfiedImportantDep == true)
1209          {
1210             if (DebugAutoInstall == true)
1211                std::clog << OutputInDepth(Depth) << "previously satisfied important dependency on "
1212                          << Start.TargetPkg().FullName() << std::endl;
1213          }
1214          else
1215          {
1216             if (DebugAutoInstall == true)
1217                std::clog << OutputInDepth(Depth) << "ignore old unsatisfied important dependency on "
1218                          << Start.TargetPkg().FullName() << std::endl;
1219             continue;
1220          }
1221       }
1222
1223       /* This bit is for processing the possibility of an install/upgrade
1224          fixing the problem for "positive" dependencies */
1225       if (Start.IsNegative() == false && (DepState[Start->ID] & DepCVer) == DepCVer)
1226       {
1227          pkgCacheFile CacheFile(this);
1228          APT::VersionList verlist = APT::VersionList::FromDependency(CacheFile, Start, APT::CacheSetHelper::CANDIDATE);
1229          CompareProviders comp(Start);
1230
1231          do {
1232             APT::VersionList::iterator InstVer = std::max_element(verlist.begin(), verlist.end(), comp);
1233
1234             if (InstVer == verlist.end())
1235                break;
1236
1237             pkgCache::PkgIterator InstPkg = InstVer.ParentPkg();
1238             if(DebugAutoInstall == true)
1239                std::clog << OutputInDepth(Depth) << "Installing " << InstPkg.Name()
1240                          << " as " << Start.DepType() << " of " << Pkg.Name()
1241                          << std::endl;
1242             if (MarkInstall(InstPkg, true, Depth + 1, false, ForceImportantDeps) == false)
1243             {
1244                verlist.erase(InstVer);
1245                continue;
1246             }
1247             break;
1248          } while(true);
1249          continue;
1250       }
1251       /* Negative dependencies have no or-group
1252          If the dependency isn't versioned, we try if an upgrade might solve the problem.
1253          Otherwise we remove the offender if needed */
1254       else if (Start.IsNegative() == true && Start->Type != pkgCache::Dep::Obsoletes)
1255       {
1256          SPtrArray<Version *> List = Start.AllTargets();
1257          pkgCache::PkgIterator TrgPkg = Start.TargetPkg();
1258          for (Version **I = List; *I != 0; I++)
1259          {
1260             VerIterator Ver(*this,*I);
1261             PkgIterator Pkg = Ver.ParentPkg();
1262
1263             /* The List includes all packages providing this dependency,
1264                even providers which are not installed, so skip them. */
1265             if (PkgState[Pkg->ID].InstallVer == 0)
1266                continue;
1267
1268             /* Ignore negative dependencies that we are not going to
1269                get installed */
1270             if (PkgState[Pkg->ID].InstallVer != *I)
1271                continue;
1272
1273             if ((Start->Version != 0 || TrgPkg != Pkg) &&
1274                 PkgState[Pkg->ID].CandidateVer != PkgState[Pkg->ID].InstallVer &&
1275                 PkgState[Pkg->ID].CandidateVer != *I &&
1276                 MarkInstall(Pkg,true,Depth + 1, false, ForceImportantDeps) == true)
1277                continue;
1278             else if (Start->Type == pkgCache::Dep::Conflicts ||
1279                      Start->Type == pkgCache::Dep::DpkgBreaks)
1280             {
1281                if(DebugAutoInstall == true)
1282                   std::clog << OutputInDepth(Depth)
1283                             << " Removing: " << Pkg.Name()
1284                             << std::endl;
1285                if (MarkDelete(Pkg,false,Depth + 1, false) == false)
1286                   break;
1287             }
1288          }
1289          continue;
1290       }
1291    }
1292
1293    return Dep.end() == true;
1294 }
1295                                                                         /*}}}*/
1296 // DepCache::IsInstallOk - check if it is ok to install this package    /*{{{*/
1297 // ---------------------------------------------------------------------
1298 /* The default implementation checks if the installation of an M-A:same
1299    package would lead us into a version-screw and if so forbids it.
1300    dpkg holds are enforced by the private IsModeChangeOk */
1301 bool pkgDepCache::IsInstallOk(PkgIterator const &Pkg,bool AutoInst,
1302                               unsigned long Depth, bool FromUser)
1303 {
1304    return IsInstallOkMultiArchSameVersionSynced(Pkg,AutoInst, Depth, FromUser) &&
1305       IsInstallOkDependenciesSatisfiableByCandidates(Pkg,AutoInst, Depth, FromUser);
1306 }
1307 bool pkgDepCache::IsInstallOkMultiArchSameVersionSynced(PkgIterator const &Pkg,
1308       bool const /*AutoInst*/, unsigned long const Depth, bool const FromUser)
1309 {
1310    if (FromUser == true) // as always: user is always right
1311       return true;
1312
1313    // if we have checked before and it was okay, it will still be okay
1314    if (PkgState[Pkg->ID].Mode == ModeInstall &&
1315          PkgState[Pkg->ID].InstallVer == PkgState[Pkg->ID].CandidateVer)
1316       return true;
1317
1318    // ignore packages with none-M-A:same candidates
1319    VerIterator const CandVer = PkgState[Pkg->ID].CandidateVerIter(*this);
1320    if (unlikely(CandVer.end() == true) || CandVer == Pkg.CurrentVer() ||
1321          (CandVer->MultiArch & pkgCache::Version::Same) != pkgCache::Version::Same)
1322       return true;
1323
1324    GrpIterator const Grp = Pkg.Group();
1325    for (PkgIterator P = Grp.PackageList(); P.end() == false; P = Grp.NextPkg(P))
1326    {
1327       // not installed or self-check: fine by definition
1328       if (P->CurrentVer == 0 || P == Pkg)
1329          continue;
1330
1331       // not having a candidate or being in sync
1332       // (simple string-compare as stuff like '1' == '0:1-0' can't happen here)
1333       VerIterator CV = PkgState[P->ID].CandidateVerIter(*this);
1334       if (CV.end() == true || strcmp(Pkg.CandVersion(), CV.VerStr()) == 0)
1335          continue;
1336
1337       // packages losing M-A:same can be out-of-sync
1338       if ((CV->MultiArch & pkgCache::Version::Same) != pkgCache::Version::Same)
1339          continue;
1340
1341       // not downloadable means the package is obsolete, so allow out-of-sync
1342       if (CV.Downloadable() == false)
1343          continue;
1344
1345       PkgState[Pkg->ID].iFlags |= AutoKept;
1346       if (unlikely(DebugMarker == true))
1347          std::clog << OutputInDepth(Depth) << "Ignore MarkInstall of " << Pkg
1348             << " as it is not in sync with its M-A:same sibling " << P
1349             << " (" << Pkg.CandVersion() << " != " << CV.VerStr() << ")" << std::endl;
1350       return false;
1351    }
1352
1353    return true;
1354 }
1355 bool pkgDepCache::IsInstallOkDependenciesSatisfiableByCandidates(PkgIterator const &Pkg,
1356       bool const AutoInst, unsigned long const Depth, bool const /*FromUser*/)
1357 {
1358    if (AutoInst == false)
1359       return true;
1360
1361    VerIterator const CandVer = PkgState[Pkg->ID].CandidateVerIter(*this);
1362    if (unlikely(CandVer.end() == true) || CandVer == Pkg.CurrentVer())
1363       return true;
1364
1365    for (DepIterator Dep = CandVer.DependsList(); Dep.end() != true;)
1366    {
1367       // Grok or groups
1368       DepIterator Start = Dep;
1369       bool Result = true;
1370       unsigned Ors = 0;
1371       for (bool LastOR = true; Dep.end() == false && LastOR == true; ++Dep, ++Ors)
1372       {
1373          LastOR = (Dep->CompareOp & Dep::Or) == Dep::Or;
1374
1375          if ((DepState[Dep->ID] & DepInstall) == DepInstall)
1376             Result = false;
1377       }
1378
1379       if (Start.IsCritical() == false || Start.IsNegative() == true || Result == false)
1380          continue;
1381
1382       /* If we are in an or group locate the first or that can succeed.
1383          We have already cached this… */
1384       for (; Ors > 1 && (DepState[Start->ID] & DepCVer) != DepCVer; --Ors)
1385          ++Start;
1386
1387       if (Ors == 1 && (DepState[Start->ID] &DepCVer) != DepCVer)
1388       {
1389          if (DebugAutoInstall == true)
1390             std::clog << OutputInDepth(Depth) << Start << " can't be satisfied!" << std::endl;
1391
1392          // the dependency is critical, but can't be installed, so discard the candidate
1393          // as the problemresolver will trip over it otherwise trying to install it (#735967)
1394          if (Pkg->CurrentVer != 0 && (PkgState[Pkg->ID].iFlags & Protected) != Protected)
1395             SetCandidateVersion(Pkg.CurrentVer());
1396          return false;
1397       }
1398    }
1399
1400    return true;
1401 }
1402                                                                         /*}}}*/
1403 // DepCache::SetReInstall - Set the reinstallation flag                 /*{{{*/
1404 // ---------------------------------------------------------------------
1405 /* */
1406 void pkgDepCache::SetReInstall(PkgIterator const &Pkg,bool To)
1407 {
1408    if (unlikely(Pkg.end() == true))
1409       return;
1410
1411    APT::PackageList pkglist;
1412    if (Pkg->CurrentVer != 0 &&
1413        (Pkg.CurrentVer()-> MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
1414    {
1415       pkgCache::GrpIterator Grp = Pkg.Group();
1416       for (pkgCache::PkgIterator P = Grp.PackageList(); P.end() == false; P = Grp.NextPkg(P))
1417       {
1418          if (P->CurrentVer != 0)
1419             pkglist.insert(P);
1420       }
1421    }
1422    else
1423       pkglist.insert(Pkg);
1424
1425    ActionGroup group(*this);
1426
1427    for (APT::PackageList::const_iterator Pkg = pkglist.begin(); Pkg != pkglist.end(); ++Pkg)
1428    {
1429       RemoveSizes(Pkg);
1430       RemoveStates(Pkg);
1431
1432       StateCache &P = PkgState[Pkg->ID];
1433       if (To == true)
1434          P.iFlags |= ReInstall;
1435       else
1436          P.iFlags &= ~ReInstall;
1437
1438       AddStates(Pkg);
1439       AddSizes(Pkg);
1440    }
1441 }
1442                                                                         /*}}}*/
1443 // DepCache::SetCandidateVersion - Change the candidate version         /*{{{*/
1444 // ---------------------------------------------------------------------
1445 /* */
1446 void pkgDepCache::SetCandidateVersion(VerIterator TargetVer)
1447 {
1448    pkgCache::PkgIterator Pkg = TargetVer.ParentPkg();
1449    StateCache &P = PkgState[Pkg->ID];
1450
1451    if (P.CandidateVer == TargetVer)
1452       return;
1453
1454    ActionGroup group(*this);
1455
1456    RemoveSizes(Pkg);
1457    RemoveStates(Pkg);
1458
1459    if (P.CandidateVer == P.InstallVer && P.Install() == true)
1460       P.InstallVer = (Version *)TargetVer;
1461    P.CandidateVer = (Version *)TargetVer;
1462    P.Update(Pkg,*this);
1463
1464    AddStates(Pkg);
1465    Update(Pkg);
1466    AddSizes(Pkg);
1467
1468 }
1469                                                                         /*}}}*/
1470 // DepCache::SetCandidateRelease - Change the candidate version         /*{{{*/
1471 // ---------------------------------------------------------------------
1472 /* changes the candidate of a package and walks over all its dependencies
1473    to check if it needs to change the candidate of the dependency, too,
1474    to reach a installable versionstate */
1475 bool pkgDepCache::SetCandidateRelease(pkgCache::VerIterator TargetVer,
1476                                         std::string const &TargetRel)
1477 {
1478    std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> > Changed;
1479    return SetCandidateRelease(TargetVer, TargetRel, Changed);
1480 }
1481 bool pkgDepCache::SetCandidateRelease(pkgCache::VerIterator TargetVer,
1482                                         std::string const &TargetRel,
1483                                         std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> > &Changed)
1484 {
1485    ActionGroup group(*this);
1486    SetCandidateVersion(TargetVer);
1487
1488    if (TargetRel == "installed" || TargetRel == "candidate") // both doesn't make sense in this context
1489       return true;
1490
1491    pkgVersionMatch Match(TargetRel, pkgVersionMatch::Release);
1492    // save the position of the last element we will not undo - if we have to
1493    std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> >::iterator newChanged = --(Changed.end());
1494
1495    for (pkgCache::DepIterator D = TargetVer.DependsList(); D.end() == false; ++D)
1496    {
1497       if (D->Type != pkgCache::Dep::PreDepends && D->Type != pkgCache::Dep::Depends &&
1498           ((D->Type != pkgCache::Dep::Recommends && D->Type != pkgCache::Dep::Suggests) ||
1499            IsImportantDep(D) == false))
1500          continue;
1501
1502       // walk over an or-group and check if we need to do anything
1503       // for simpilicity no or-group is handled as a or-group including one dependency
1504       pkgCache::DepIterator Start = D;
1505       bool itsFine = false;
1506       for (bool stillOr = true; stillOr == true; ++Start)
1507       {
1508          stillOr = (Start->CompareOp & Dep::Or) == Dep::Or;
1509          pkgCache::PkgIterator const P = Start.TargetPkg();
1510          // virtual packages can't be a solution
1511          if (P.end() == true || (P->ProvidesList == 0 && P->VersionList == 0))
1512             continue;
1513          pkgCache::VerIterator const Cand = PkgState[P->ID].CandidateVerIter(*this);
1514          // no versioned dependency - but is it installable?
1515          if (Start.TargetVer() == 0 || Start.TargetVer()[0] == '\0')
1516          {
1517             // Check if one of the providers is installable
1518             if (P->ProvidesList != 0)
1519             {
1520                pkgCache::PrvIterator Prv = P.ProvidesList();
1521                for (; Prv.end() == false; ++Prv)
1522                {
1523                   pkgCache::VerIterator const C = PkgState[Prv.OwnerPkg()->ID].CandidateVerIter(*this);
1524                   if (C.end() == true || C != Prv.OwnerVer() ||
1525                       (VersionState(C.DependsList(), DepInstall, DepCandMin, DepCandPolicy) & DepCandMin) != DepCandMin)
1526                      continue;
1527                   break;
1528                }
1529                if (Prv.end() == true)
1530                   continue;
1531             }
1532             // no providers, so check if we have an installable candidate version
1533             else if (Cand.end() == true ||
1534                 (VersionState(Cand.DependsList(), DepInstall, DepCandMin, DepCandPolicy) & DepCandMin) != DepCandMin)
1535                continue;
1536             itsFine = true;
1537             break;
1538          }
1539          if (Cand.end() == true)
1540             continue;
1541          // check if the current candidate is enough for the versioned dependency - and installable?
1542          if (Start.IsSatisfied(Cand) == true &&
1543              (VersionState(Cand.DependsList(), DepInstall, DepCandMin, DepCandPolicy) & DepCandMin) == DepCandMin)
1544          {
1545             itsFine = true;
1546             break;
1547          }
1548       }
1549
1550       if (itsFine == true) {
1551          // something in the or-group was fine, skip all other members
1552          for (; (D->CompareOp & Dep::Or) == Dep::Or; ++D);
1553          continue;
1554       }
1555
1556       // walk again over the or-group and check each if a candidate switch would help
1557       itsFine = false;
1558       for (bool stillOr = true; stillOr == true; ++D)
1559       {
1560          stillOr = (D->CompareOp & Dep::Or) == Dep::Or;
1561          // changing candidate will not help if the dependency is not versioned
1562          if (D.TargetVer() == 0 || D.TargetVer()[0] == '\0')
1563          {
1564             if (stillOr == true)
1565                continue;
1566             break;
1567          }
1568
1569          pkgCache::VerIterator V;
1570          if (TargetRel == "newest")
1571             V = D.TargetPkg().VersionList();
1572          else
1573             V = Match.Find(D.TargetPkg());
1574
1575          // check if the version from this release could satisfy the dependency
1576          if (V.end() == true || D.IsSatisfied(V) == false)
1577          {
1578             if (stillOr == true)
1579                continue;
1580             break;
1581          }
1582
1583          pkgCache::VerIterator oldCand = PkgState[D.TargetPkg()->ID].CandidateVerIter(*this);
1584          if (V == oldCand)
1585          {
1586             // Do we already touched this Version? If so, their versioned dependencies are okay, no need to check again
1587             for (std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> >::const_iterator c = Changed.begin();
1588                  c != Changed.end(); ++c)
1589             {
1590                if (c->first->ParentPkg != V->ParentPkg)
1591                   continue;
1592                itsFine = true;
1593                break;
1594             }
1595          }
1596
1597          if (itsFine == false)
1598          {
1599             // change the candidate
1600             Changed.push_back(make_pair(V, TargetVer));
1601             if (SetCandidateRelease(V, TargetRel, Changed) == false)
1602             {
1603                if (stillOr == false)
1604                   break;
1605                // undo the candidate changing
1606                SetCandidateVersion(oldCand);
1607                Changed.pop_back();
1608                continue;
1609             }
1610             itsFine = true;
1611          }
1612
1613          // something in the or-group was fine, skip all other members
1614          for (; (D->CompareOp & Dep::Or) == Dep::Or; ++D);
1615          break;
1616       }
1617
1618       if (itsFine == false && (D->Type == pkgCache::Dep::PreDepends || D->Type == pkgCache::Dep::Depends))
1619       {
1620          // undo all changes which aren't lead to a solution
1621          for (std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> >::const_iterator c = ++newChanged;
1622               c != Changed.end(); ++c)
1623             SetCandidateVersion(c->first);
1624          Changed.erase(newChanged, Changed.end());
1625          return false;
1626       }
1627    }
1628    return true;
1629 }
1630                                                                         /*}}}*/
1631 // DepCache::MarkAuto - set the Auto flag for a package                 /*{{{*/
1632 // ---------------------------------------------------------------------
1633 /* */
1634 void pkgDepCache::MarkAuto(const PkgIterator &Pkg, bool Auto)
1635 {
1636   StateCache &state = PkgState[Pkg->ID];
1637
1638   ActionGroup group(*this);
1639
1640   if(Auto)
1641     state.Flags |= Flag::Auto;
1642   else
1643     state.Flags &= ~Flag::Auto;
1644 }
1645                                                                         /*}}}*/
1646 // StateCache::Update - Compute the various static display things       /*{{{*/
1647 // ---------------------------------------------------------------------
1648 /* This is called whenever the Candidate version changes. */
1649 void pkgDepCache::StateCache::Update(PkgIterator Pkg,pkgCache &Cache)
1650 {
1651    // Some info
1652    VerIterator Ver = CandidateVerIter(Cache);
1653
1654    // Use a null string or the version string
1655    if (Ver.end() == true)
1656       CandVersion = "";
1657    else
1658       CandVersion = Ver.VerStr();
1659
1660    // Find the current version
1661    CurVersion = "";
1662    if (Pkg->CurrentVer != 0)
1663       CurVersion = Pkg.CurrentVer().VerStr();
1664
1665    // Strip off the epochs for display
1666    CurVersion = StripEpoch(CurVersion);
1667    CandVersion = StripEpoch(CandVersion);
1668
1669    // Figure out if its up or down or equal
1670    Status = Ver.CompareVer(Pkg.CurrentVer());
1671    if (Pkg->CurrentVer == 0 || Pkg->VersionList == 0 || CandidateVer == 0)
1672      Status = 2;
1673 }
1674                                                                         /*}}}*/
1675 // StateCache::StripEpoch - Remove the epoch specifier from the version /*{{{*/
1676 // ---------------------------------------------------------------------
1677 /* */
1678 const char *pkgDepCache::StateCache::StripEpoch(const char *Ver)
1679 {
1680    if (Ver == 0)
1681       return 0;
1682
1683    // Strip any epoch
1684    char const * const I = strchr(Ver, ':');
1685    if (I == nullptr)
1686       return Ver;
1687    return I + 1;
1688 }
1689                                                                         /*}}}*/
1690 // Policy::GetCandidateVer - Returns the Candidate install version      /*{{{*/
1691 // ---------------------------------------------------------------------
1692 /* The default just returns the highest available version that is not
1693    a source and automatic. */
1694 pkgCache::VerIterator pkgDepCache::Policy::GetCandidateVer(PkgIterator const &Pkg)
1695 {
1696    /* Not source/not automatic versions cannot be a candidate version
1697       unless they are already installed */
1698    VerIterator Last;
1699
1700    for (VerIterator I = Pkg.VersionList(); I.end() == false; ++I)
1701    {
1702       if (Pkg.CurrentVer() == I)
1703          return I;
1704
1705       for (VerFileIterator J = I.FileList(); J.end() == false; ++J)
1706       {
1707          if (J.File().Flagged(Flag::NotSource))
1708             continue;
1709
1710          /* Stash the highest version of a not-automatic source, we use it
1711             if there is nothing better */
1712          if (J.File().Flagged(Flag::NotAutomatic) ||
1713              J.File().Flagged(Flag::ButAutomaticUpgrades))
1714          {
1715             if (Last.end() == true)
1716                Last = I;
1717             continue;
1718          }
1719
1720          return I;
1721       }
1722    }
1723
1724    return Last;
1725 }
1726                                                                         /*}}}*/
1727 // Policy::IsImportantDep - True if the dependency is important         /*{{{*/
1728 // ---------------------------------------------------------------------
1729 /* */
1730 bool pkgDepCache::Policy::IsImportantDep(DepIterator const &Dep) const
1731 {
1732    if(Dep.IsCritical())
1733       return true;
1734    else if(Dep->Type == pkgCache::Dep::Recommends)
1735    {
1736       if (InstallRecommends)
1737          return true;
1738       // we suport a special mode to only install-recommends for certain
1739       // sections
1740       // FIXME: this is a meant as a temporarly solution until the
1741       //        recommends are cleaned up
1742       const char *sec = Dep.ParentVer().Section();
1743       if (sec && ConfigValueInSubTree("APT::Install-Recommends-Sections", sec))
1744          return true;
1745    }
1746    else if(Dep->Type == pkgCache::Dep::Suggests)
1747       return InstallSuggests;
1748
1749    return false;
1750 }
1751                                                                         /*}}}*/
1752 // Policy::GetPriority - Get the priority of the package pin            /*{{{*/
1753 APT_CONST signed short pkgDepCache::Policy::GetPriority(pkgCache::PkgIterator const &/*Pkg*/)
1754 { return 0; }
1755 APT_CONST signed short pkgDepCache::Policy::GetPriority(pkgCache::PkgFileIterator const &/*File*/)
1756 { return 0; }
1757                                                                         /*}}}*/
1758 pkgDepCache::InRootSetFunc *pkgDepCache::GetRootSetFunc()               /*{{{*/
1759 {
1760   DefaultRootSetFunc *f = new DefaultRootSetFunc;
1761   if(f->wasConstructedSuccessfully())
1762     return f;
1763   else
1764     {
1765       delete f;
1766       return NULL;
1767     }
1768 }
1769                                                                         /*}}}*/
1770 bool pkgDepCache::MarkFollowsRecommends()
1771 {
1772   return _config->FindB("APT::AutoRemove::RecommendsImportant", true);
1773 }
1774
1775 bool pkgDepCache::MarkFollowsSuggests()
1776 {
1777   return _config->FindB("APT::AutoRemove::SuggestsImportant", true);
1778 }
1779
1780 // pkgDepCache::MarkRequired - the main mark algorithm                  /*{{{*/
1781 bool pkgDepCache::MarkRequired(InRootSetFunc &userFunc)
1782 {
1783    if (_config->Find("APT::Solver", "internal") != "internal")
1784       return true;
1785
1786    bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
1787
1788    // init the states
1789    map_id_t const PackagesCount = Head().PackageCount;
1790    for(map_id_t i = 0; i < PackagesCount; ++i)
1791    {
1792       PkgState[i].Marked  = false;
1793       PkgState[i].Garbage = false;
1794    }
1795    if (debug_autoremove)
1796       for(PkgIterator p = PkgBegin(); !p.end(); ++p)
1797          if(PkgState[p->ID].Flags & Flag::Auto)
1798             std::clog << "AutoDep: " << p.FullName() << std::endl;
1799
1800    bool const follow_recommends = MarkFollowsRecommends();
1801    bool const follow_suggests   = MarkFollowsSuggests();
1802
1803    // do the mark part, this is the core bit of the algorithm
1804    for(PkgIterator p = PkgBegin(); !p.end(); ++p)
1805    {
1806       if(!(PkgState[p->ID].Flags & Flag::Auto) ||
1807           (p->Flags & Flag::Essential) ||
1808           (p->Flags & Flag::Important) ||
1809           userFunc.InRootSet(p) ||
1810           // be nice even then a required package violates the policy (#583517)
1811           // and do the full mark process also for required packages
1812           (p.CurrentVer().end() != true &&
1813            p.CurrentVer()->Priority == pkgCache::State::Required) ||
1814           // packages which can't be changed (like holds) can't be garbage
1815           (IsModeChangeOk(ModeGarbage, p, 0, false) == false))
1816       {
1817          // the package is installed (and set to keep)
1818          if(PkgState[p->ID].Keep() && !p.CurrentVer().end())
1819             MarkPackage(p, p.CurrentVer(),
1820                         follow_recommends, follow_suggests);
1821          // the package is to be installed
1822          else if(PkgState[p->ID].Install())
1823             MarkPackage(p, PkgState[p->ID].InstVerIter(*this),
1824                         follow_recommends, follow_suggests);
1825       }
1826    }
1827
1828    return true;
1829 }
1830                                                                         /*}}}*/
1831 // MarkPackage - mark a single package in Mark-and-Sweep                /*{{{*/
1832 void pkgDepCache::MarkPackage(const pkgCache::PkgIterator &pkg,
1833                               const pkgCache::VerIterator &ver,
1834                               bool const &follow_recommends,
1835                               bool const &follow_suggests)
1836 {
1837    pkgDepCache::StateCache &state = PkgState[pkg->ID];
1838
1839    // if we are marked already we are done
1840    if(state.Marked)
1841       return;
1842
1843    VerIterator const currver = pkg.CurrentVer();
1844    VerIterator const instver = state.InstVerIter(*this);
1845
1846 #if 0
1847    VerIterator const candver = state.CandidateVerIter(*this);
1848
1849    // If a package was garbage-collected but is now being marked, we
1850    // should re-select it
1851    // For cases when a pkg is set to upgrade and this trigger the
1852    // removal of a no-longer used dependency.  if the pkg is set to
1853    // keep again later it will result in broken deps
1854    if(state.Delete() && state.RemoveReason = Unused)
1855    {
1856       if(ver==candver)
1857          mark_install(pkg, false, false, NULL);
1858       else if(ver==pkg.CurrentVer())
1859          MarkKeep(pkg, false, false);
1860
1861       instver=state.InstVerIter(*this);
1862    }
1863 #endif
1864
1865    // For packages that are not going to be removed, ignore versions
1866    // other than the InstVer.  For packages that are going to be
1867    // removed, ignore versions other than the current version.
1868    if(!(ver == instver && !instver.end()) &&
1869       !(ver == currver && instver.end() && !ver.end()))
1870       return;
1871
1872    bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove", false);
1873
1874    if(debug_autoremove)
1875      {
1876        std::clog << "Marking: " << pkg.FullName();
1877        if(!ver.end())
1878          std::clog << " " << ver.VerStr();
1879        if(!currver.end())
1880          std::clog << ", Curr=" << currver.VerStr();
1881        if(!instver.end())
1882          std::clog << ", Inst=" << instver.VerStr();
1883        std::clog << std::endl;
1884      }
1885
1886    state.Marked=true;
1887
1888    if(ver.end() == true)
1889       return;
1890
1891      for(DepIterator d = ver.DependsList(); !d.end(); ++d)
1892      {
1893         if(d->Type == Dep::Depends ||
1894            d->Type == Dep::PreDepends ||
1895            (follow_recommends &&
1896             d->Type == Dep::Recommends) ||
1897            (follow_suggests &&
1898             d->Type == Dep::Suggests))
1899         {
1900            // Try all versions of this package.
1901            for(VerIterator V = d.TargetPkg().VersionList();
1902                !V.end(); ++V)
1903            {
1904               if(d.IsSatisfied(V))
1905               {
1906                 if(debug_autoremove)
1907                   {
1908                     std::clog << "Following dep: " << d.ParentPkg().FullName()
1909                               << " " << d.ParentVer().VerStr() << " "
1910                               << d.DepType() << " " << d.TargetPkg().FullName();
1911                     if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
1912                       {
1913                         std::clog << " (" << d.CompType() << " "
1914                                   << d.TargetVer() << ")";
1915                       }
1916                     std::clog << std::endl;
1917                   }
1918                  MarkPackage(V.ParentPkg(), V,
1919                              follow_recommends, follow_suggests);
1920               }
1921            }
1922            // Now try virtual packages
1923            for(PrvIterator prv=d.TargetPkg().ProvidesList();
1924                !prv.end(); ++prv)
1925            {
1926               if(d.IsSatisfied(prv))
1927               {
1928                 if(debug_autoremove)
1929                   {
1930                     std::clog << "Following dep: " << d.ParentPkg().FullName() << " "
1931                               << d.ParentVer().VerStr() << " "
1932                               << d.DepType() << " " << d.TargetPkg().FullName() << " ";
1933                     if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
1934                       {
1935                         std::clog << " (" << d.CompType() << " "
1936                                   << d.TargetVer() << ")";
1937                       }
1938                     std::clog << ", provided by "
1939                               << prv.OwnerPkg().FullName() << " "
1940                               << prv.OwnerVer().VerStr()
1941                               << std::endl;
1942                   }
1943
1944                  MarkPackage(prv.OwnerPkg(), prv.OwnerVer(),
1945                              follow_recommends, follow_suggests);
1946               }
1947            }
1948         }
1949      }
1950 }
1951                                                                         /*}}}*/
1952 bool pkgDepCache::Sweep()                                               /*{{{*/
1953 {
1954    bool debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
1955
1956    // do the sweep
1957    for(PkgIterator p=PkgBegin(); !p.end(); ++p)
1958    {
1959      StateCache &state=PkgState[p->ID];
1960
1961      // skip required packages
1962      if (!p.CurrentVer().end() &&
1963          (p.CurrentVer()->Priority == pkgCache::State::Required))
1964         continue;
1965
1966      // if it is not marked and it is installed, it's garbage
1967      if(!state.Marked && (!p.CurrentVer().end() || state.Install()))
1968      {
1969         state.Garbage=true;
1970         if(debug_autoremove)
1971            std::clog << "Garbage: " << p.FullName() << std::endl;
1972      }
1973   }
1974
1975    return true;
1976 }
1977                                                                         /*}}}*/
1978 // DepCache::MarkAndSweep                                               /*{{{*/
1979 bool pkgDepCache::MarkAndSweep(InRootSetFunc &rootFunc)
1980 {
1981    return MarkRequired(rootFunc) && Sweep();
1982 }
1983 bool pkgDepCache::MarkAndSweep()
1984 {
1985    std::auto_ptr<InRootSetFunc> f(GetRootSetFunc());
1986    if(f.get() != NULL)
1987       return MarkAndSweep(*f.get());
1988    else
1989       return false;
1990 }
1991                                                                         /*}}}*/