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 <apt-pkg/depcache.h>
  12 #include <apt-pkg/version.h>
  13 #include <apt-pkg/error.h>
  14 #include <apt-pkg/sptr.h>
  15 #include <apt-pkg/algorithms.h>
  16
  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/pkgsystem.h>
  22 #include <apt-pkg/tagfile.h>
  23
  24 #include <iostream>
  25 #include <sstream>
  26 #include <set>
  27
  28 #include <sys/stat.h>
  29
  30 #include <apti18n.h>
  31                                                                         /*}}}*/
  32 // helper for Install-Recommends-Sections and Never-MarkAuto-Sections   /*{{{*/
  33 static bool
  34 ConfigValueInSubTree(const char* SubTree, const char *needle)
  35 {
  36    Configuration::Item const *Opts;
  37    Opts = _config->Tree(SubTree);
  38    if (Opts != 0 && Opts->Child != 0)
  39    {
  40       Opts = Opts->Child;
  41       for (; Opts != 0; Opts = Opts->Next)
  42       {
  43          if (Opts->Value.empty() == true)
  44             continue;
  45          if (strcmp(needle, Opts->Value.c_str()) == 0)
  46             return true;
  47       }
  48    }
  49    return false;
  50 }
  51                                                                         /*}}}*/
  52 pkgDepCache::ActionGroup::ActionGroup(pkgDepCache &cache) :             /*{{{*/
  53   cache(cache), released(false)
  54 {
  55   ++cache.group_level;
  56 }
  57
  58 void pkgDepCache::ActionGroup::release()
  59 {
  60   if(!released)
  61     {
  62       if(cache.group_level == 0)
  63         std::cerr << "W: Unbalanced action groups, expect badness" << std::endl;
  64       else
  65         {
  66           --cache.group_level;
  67
  68           if(cache.group_level == 0)
  69             cache.MarkAndSweep();
  70         }
  71
  72       released = false;
  73     }
  74 }
  75
  76 pkgDepCache::ActionGroup::~ActionGroup()
  77 {
  78   release();
  79 }
  80                                                                         /*}}}*/
  81 // DepCache::pkgDepCache - Constructors                                 /*{{{*/
  82 // ---------------------------------------------------------------------
  83 /* */
  84 pkgDepCache::pkgDepCache(pkgCache *pCache,Policy *Plcy) :
  85   group_level(0), Cache(pCache), PkgState(0), DepState(0)
  86 {
  87    DebugMarker = _config->FindB("Debug::pkgDepCache::Marker", false);
  88    DebugAutoInstall = _config->FindB("Debug::pkgDepCache::AutoInstall", false);
  89    delLocalPolicy = 0;
  90    LocalPolicy = Plcy;
  91    if (LocalPolicy == 0)
  92       delLocalPolicy = LocalPolicy = new Policy;
  93 }
  94                                                                         /*}}}*/
  95 // DepCache::~pkgDepCache - Destructor                                  /*{{{*/
  96 // ---------------------------------------------------------------------
  97 /* */
  98 pkgDepCache::~pkgDepCache()
  99 {
 100    delete [] PkgState;
 101    delete [] DepState;
 102    delete delLocalPolicy;
 103 }
 104                                                                         /*}}}*/
 105 // DepCache::Init - Generate the initial extra structures.              /*{{{*/
 106 // ---------------------------------------------------------------------
 107 /* This allocats the extension buffers and initializes them. */
 108 bool pkgDepCache::Init(OpProgress *Prog)
 109 {
 110    // Suppress mark updates during this operation (just in case) and
 111    // run a mark operation when Init terminates.
 112    ActionGroup actions(*this);
 113
 114    delete [] PkgState;
 115    delete [] DepState;
 116    PkgState = new StateCache[Head().PackageCount];
 117    DepState = new unsigned char[Head().DependsCount];
 118    memset(PkgState,0,sizeof(*PkgState)*Head().PackageCount);
 119    memset(DepState,0,sizeof(*DepState)*Head().DependsCount);
 120
 121    if (Prog != 0)
 122    {
 123       Prog->OverallProgress(0,2*Head().PackageCount,Head().PackageCount,
 124                             _("Building dependency tree"));
 125       Prog->SubProgress(Head().PackageCount,_("Candidate versions"));
 126    }
 127
 128    /* Set the current state of everything. In this state all of the
 129       packages are kept exactly as is. See AllUpgrade */
 130    int Done = 0;
 131    for (PkgIterator I = PkgBegin(); I.end() != true; I++,Done++)
 132    {
 133       if (Prog != 0 && Done%20 == 0)
 134          Prog->Progress(Done);
 135
 136       // Find the proper cache slot
 137       StateCache &State = PkgState[I->ID];
 138       State.iFlags = 0;
 139
 140       // Figure out the install version
 141       State.CandidateVer = GetCandidateVer(I);
 142       State.InstallVer = I.CurrentVer();
 143       State.Mode = ModeKeep;
 144
 145       State.Update(I,*this);
 146    }
 147
 148    if (Prog != 0)
 149    {
 150
 151       Prog->OverallProgress(Head().PackageCount,2*Head().PackageCount,
 152                             Head().PackageCount,
 153                             _("Building dependency tree"));
 154       Prog->SubProgress(Head().PackageCount,_("Dependency generation"));
 155    }
 156
 157    Update(Prog);
 158
 159    if(Prog != 0)
 160       Prog->Done();
 161
 162    return true;
 163 }
 164                                                                         /*}}}*/
 165 bool pkgDepCache::readStateFile(OpProgress *Prog)                       /*{{{*/
 166 {
 167    FileFd state_file;
 168    string const state = _config->FindFile("Dir::State::extended_states");
 169    if(FileExists(state)) {
 170       state_file.Open(state, FileFd::ReadOnly);
 171       int const file_size = state_file.Size();
 172       if(Prog != NULL)
 173          Prog->OverallProgress(0, file_size, 1,
 174                                _("Reading state information"));
 175
 176       pkgTagFile tagfile(&state_file);
 177       pkgTagSection section;
 178       int amt = 0;
 179       bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
 180       while(tagfile.Step(section)) {
 181          string const pkgname = section.FindS("Package");
 182          string pkgarch = section.FindS("Architecture");
 183          if (pkgarch.empty() == true)
 184             pkgarch = "any";
 185          pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
 186          // Silently ignore unknown packages and packages with no actual version.
 187          if(pkg.end() == true || pkg->VersionList == 0)
 188             continue;
 189
 190          short const reason = section.FindI("Auto-Installed", 0);
 191          if(reason > 0)
 192          {
 193             PkgState[pkg->ID].Flags |= Flag::Auto;
 194             if (unlikely(debug_autoremove))
 195                std::clog << "Auto-Installed : " << pkg.FullName() << std::endl;
 196             if (pkgarch == "any")
 197             {
 198                pkgCache::GrpIterator G = pkg.Group();
 199                for (pkg = G.NextPkg(pkg); pkg.end() != true; pkg = G.NextPkg(pkg))
 200                   if (pkg->VersionList != 0)
 201                      PkgState[pkg->ID].Flags |= Flag::Auto;
 202             }
 203          }
 204          amt += section.size();
 205          if(Prog != NULL)
 206             Prog->OverallProgress(amt, file_size, 1,
 207                                   _("Reading state information"));
 208       }
 209       if(Prog != NULL)
 210          Prog->OverallProgress(file_size, file_size, 1,
 211                                _("Reading state information"));
 212    }
 213
 214    return true;
 215 }
 216                                                                         /*}}}*/
 217 bool pkgDepCache::writeStateFile(OpProgress *prog, bool InstalledOnly)  /*{{{*/
 218 {
 219    bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
 220
 221    if(debug_autoremove)
 222       std::clog << "pkgDepCache::writeStateFile()" << std::endl;
 223
 224    FileFd StateFile;
 225    string const state = _config->FindFile("Dir::State::extended_states");
 226
 227    // if it does not exist, create a empty one
 228    if(!FileExists(state))
 229    {
 230       StateFile.Open(state, FileFd::WriteEmpty);
 231       StateFile.Close();
 232    }
 233
 234    // open it
 235    if(!StateFile.Open(state, FileFd::ReadOnly))
 236       return _error->Error(_("Failed to open StateFile %s"),
 237                            state.c_str());
 238
 239    FILE *OutFile;
 240    string const outfile = state + ".tmp";
 241    if((OutFile = fopen(outfile.c_str(),"w")) == NULL)
 242       return _error->Error(_("Failed to write temporary StateFile %s"),
 243                            outfile.c_str());
 244
 245    // first merge with the existing sections
 246    pkgTagFile tagfile(&StateFile);
 247    pkgTagSection section;
 248    std::set<string> pkgs_seen;
 249    const char *nullreorderlist[] = {0};
 250    while(tagfile.Step(section)) {
 251          string const pkgname = section.FindS("Package");
 252          string pkgarch = section.FindS("Architecture");
 253          if (pkgarch.empty() == true)
 254             pkgarch = "native";
 255          // Silently ignore unknown packages and packages with no actual
 256          // version.
 257          pkgCache::PkgIterator pkg = Cache->FindPkg(pkgname, pkgarch);
 258          if(pkg.end() || pkg.VersionList().end())
 259             continue;
 260          StateCache const &P = PkgState[pkg->ID];
 261          bool newAuto = (P.Flags & Flag::Auto);
 262          // skip not installed or now-removed ones if requested
 263          if (InstalledOnly && (
 264              (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
 265              (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
 266          {
 267             // The section is obsolete if it contains no other tag
 268             unsigned int const count = section.Count();
 269             if (count < 2 ||
 270                 (count == 2 && section.Exists("Auto-Installed")) ||
 271                 (count == 3 && section.Exists("Auto-Installed") && section.Exists("Architecture")))
 272                continue;
 273             else
 274                newAuto = false;
 275          }
 276          if(_config->FindB("Debug::pkgAutoRemove",false))
 277             std::clog << "Update existing AutoInstall info: "
 278                       << pkg.FullName() << std::endl;
 279          TFRewriteData rewrite[3];
 280          rewrite[0].Tag = "Architecture";
 281          rewrite[0].Rewrite = pkg.Arch();
 282          rewrite[0].NewTag = 0;
 283          rewrite[1].Tag = "Auto-Installed";
 284          rewrite[1].Rewrite = newAuto ? "1" : "0";
 285          rewrite[1].NewTag = 0;
 286          rewrite[2].Tag = 0;
 287          TFRewrite(OutFile, section, nullreorderlist, rewrite);
 288          fprintf(OutFile,"\n");
 289          pkgs_seen.insert(pkg.FullName());
 290    }
 291
 292    // then write the ones we have not seen yet
 293    std::ostringstream ostr;
 294    for(pkgCache::PkgIterator pkg=Cache->PkgBegin(); !pkg.end(); pkg++) {
 295       StateCache const &P = PkgState[pkg->ID];
 296       if(P.Flags & Flag::Auto) {
 297          if (pkgs_seen.find(pkg.FullName()) != pkgs_seen.end()) {
 298             if(debug_autoremove)
 299                std::clog << "Skipping already written " << pkg.FullName() << std::endl;
 300             continue;
 301          }
 302          // skip not installed ones if requested
 303          if (InstalledOnly && (
 304              (pkg->CurrentVer == 0 && P.Mode != ModeInstall) ||
 305              (pkg->CurrentVer != 0 && P.Mode == ModeDelete)))
 306             continue;
 307          const char* const pkgarch = pkg.Arch();
 308          if (strcmp(pkgarch, "all") == 0)
 309             continue;
 310          if(debug_autoremove)
 311             std::clog << "Writing new AutoInstall: " << pkg.FullName() << std::endl;
 312          ostr.str(string(""));
 313          ostr << "Package: " << pkg.Name()
 314               << "\nArchitecture: " << pkgarch
 315               << "\nAuto-Installed: 1\n\n";
 316          fprintf(OutFile,"%s",ostr.str().c_str());
 317       }
 318    }
 319    fclose(OutFile);
 320
 321    // move the outfile over the real file and set permissions
 322    rename(outfile.c_str(), state.c_str());
 323    chmod(state.c_str(), 0644);
 324
 325    return true;
 326 }
 327                                                                         /*}}}*/
 328 // DepCache::CheckDep - Checks a single dependency                      /*{{{*/
 329 // ---------------------------------------------------------------------
 330 /* This first checks the dependency against the main target package and
 331    then walks along the package provides list and checks if each provides
 332    will be installed then checks the provides against the dep. Res will be
 333    set to the package which was used to satisfy the dep. */
 334 bool pkgDepCache::CheckDep(DepIterator Dep,int Type,PkgIterator &Res)
 335 {
 336    Res = Dep.TargetPkg();
 337
 338    /* Check simple depends. A depends -should- never self match but
 339       we allow it anyhow because dpkg does. Technically it is a packaging
 340       bug. Conflicts may never self match */
 341    if (Dep.TargetPkg() != Dep.ParentPkg() ||
 342        (Dep->Type != Dep::Conflicts && Dep->Type != Dep::DpkgBreaks && Dep->Type != Dep::Obsoletes))
 343    {
 344       PkgIterator Pkg = Dep.TargetPkg();
 345       // Check the base package
 346       if (Type == NowVersion && Pkg->CurrentVer != 0)
 347          if (VS().CheckDep(Pkg.CurrentVer().VerStr(),Dep->CompareOp,
 348                                  Dep.TargetVer()) == true)
 349             return true;
 350
 351       if (Type == InstallVersion && PkgState[Pkg->ID].InstallVer != 0)
 352          if (VS().CheckDep(PkgState[Pkg->ID].InstVerIter(*this).VerStr(),
 353                                  Dep->CompareOp,Dep.TargetVer()) == true)
 354             return true;
 355
 356       if (Type == CandidateVersion && PkgState[Pkg->ID].CandidateVer != 0)
 357          if (VS().CheckDep(PkgState[Pkg->ID].CandidateVerIter(*this).VerStr(),
 358                                  Dep->CompareOp,Dep.TargetVer()) == true)
 359             return true;
 360    }
 361
 362    if (Dep->Type == Dep::Obsoletes)
 363       return false;
 364
 365    // Check the providing packages
 366    PrvIterator P = Dep.TargetPkg().ProvidesList();
 367    PkgIterator Pkg = Dep.ParentPkg();
 368    for (; P.end() != true; P++)
 369    {
 370       /* Provides may never be applied against the same package if it is
 371          a conflicts. See the comment above. */
 372       if (P.OwnerPkg() == Pkg &&
 373           (Dep->Type == Dep::Conflicts || Dep->Type == Dep::DpkgBreaks))
 374          continue;
 375
 376       // Check if the provides is a hit
 377       if (Type == NowVersion)
 378       {
 379          if (P.OwnerPkg().CurrentVer() != P.OwnerVer())
 380             continue;
 381       }
 382
 383       if (Type == InstallVersion)
 384       {
 385          StateCache &State = PkgState[P.OwnerPkg()->ID];
 386          if (State.InstallVer != (Version *)P.OwnerVer())
 387             continue;
 388       }
 389
 390       if (Type == CandidateVersion)
 391       {
 392          StateCache &State = PkgState[P.OwnerPkg()->ID];
 393          if (State.CandidateVer != (Version *)P.OwnerVer())
 394             continue;
 395       }
 396
 397       // Compare the versions.
 398       if (VS().CheckDep(P.ProvideVersion(),Dep->CompareOp,Dep.TargetVer()) == true)
 399       {
 400          Res = P.OwnerPkg();
 401          return true;
 402       }
 403    }
 404
 405    return false;
 406 }
 407                                                                         /*}}}*/
 408 // DepCache::AddSizes - Add the packages sizes to the counters          /*{{{*/
 409 // ---------------------------------------------------------------------
 410 /* Call with Mult = -1 to preform the inverse opration
 411    The Mult increases the complexity of the calulations here and is unused -
 412    or do we really have a usecase for removing the size of a package two
 413    times? So let us replace it with a simple bool and be done with it… */
 414 __deprecated void pkgDepCache::AddSizes(const PkgIterator &Pkg,signed long Mult)
 415 {
 416    StateCache &P = PkgState[Pkg->ID];
 417
 418    if (Pkg->VersionList == 0)
 419       return;
 420
 421    if (Pkg.State() == pkgCache::PkgIterator::NeedsConfigure &&
 422        P.Keep() == true)
 423       return;
 424
 425    // Compute the size data
 426    if (P.NewInstall() == true)
 427    {
 428       iUsrSize += (signed long long)(Mult*P.InstVerIter(*this)->InstalledSize);
 429       iDownloadSize += (signed long long)(Mult*P.InstVerIter(*this)->Size);
 430       return;
 431    }
 432
 433    // Upgrading
 434    if (Pkg->CurrentVer != 0 &&
 435        (P.InstallVer != (Version *)Pkg.CurrentVer() ||
 436         (P.iFlags & ReInstall) == ReInstall) && P.InstallVer != 0)
 437    {
 438       iUsrSize += (signed long long)(Mult*((signed long long)P.InstVerIter(*this)->InstalledSize -
 439                         (signed long long)Pkg.CurrentVer()->InstalledSize));
 440       iDownloadSize += (signed long long)(Mult*P.InstVerIter(*this)->Size);
 441       return;
 442    }
 443
 444    // Reinstall
 445    if (Pkg.State() == pkgCache::PkgIterator::NeedsUnpack &&
 446        P.Delete() == false)
 447    {
 448       iDownloadSize += (signed long long)(Mult*P.InstVerIter(*this)->Size);
 449       return;
 450    }
 451
 452    // Removing
 453    if (Pkg->CurrentVer != 0 && P.InstallVer == 0)
 454    {
 455       iUsrSize -= (signed long long)(Mult*Pkg.CurrentVer()->InstalledSize);
 456       return;
 457    }
 458 }
 459                                                                         /*}}}*/
 460 // DepCache::AddSizes - Add the packages sizes to the counters          /*{{{*/
 461 // ---------------------------------------------------------------------
 462 /* Call with Inverse = true to preform the inverse opration */
 463 void pkgDepCache::AddSizes(const PkgIterator &Pkg, bool const &Inverse)
 464 {
 465    StateCache &P = PkgState[Pkg->ID];
 466
 467    if (Pkg->VersionList == 0)
 468       return;
 469
 470    if (Pkg.State() == pkgCache::PkgIterator::NeedsConfigure &&
 471        P.Keep() == true)
 472       return;
 473
 474    // Compute the size data
 475    if (P.NewInstall() == true)
 476    {
 477       if (Inverse == false) {
 478          iUsrSize += P.InstVerIter(*this)->InstalledSize;
 479          iDownloadSize += P.InstVerIter(*this)->Size;
 480       } else {
 481          iUsrSize -= P.InstVerIter(*this)->InstalledSize;
 482          iDownloadSize -= P.InstVerIter(*this)->Size;
 483       }
 484       return;
 485    }
 486
 487    // Upgrading
 488    if (Pkg->CurrentVer != 0 &&
 489        (P.InstallVer != (Version *)Pkg.CurrentVer() ||
 490         (P.iFlags & ReInstall) == ReInstall) && P.InstallVer != 0)
 491    {
 492       if (Inverse == false) {
 493          iUsrSize -= Pkg.CurrentVer()->InstalledSize;
 494          iUsrSize += P.InstVerIter(*this)->InstalledSize;
 495          iDownloadSize += P.InstVerIter(*this)->Size;
 496       } else {
 497          iUsrSize -= P.InstVerIter(*this)->InstalledSize;
 498          iUsrSize += Pkg.CurrentVer()->InstalledSize;
 499          iDownloadSize -= P.InstVerIter(*this)->Size;
 500       }
 501       return;
 502    }
 503
 504    // Reinstall
 505    if (Pkg.State() == pkgCache::PkgIterator::NeedsUnpack &&
 506        P.Delete() == false)
 507    {
 508       if (Inverse == false)
 509          iDownloadSize += P.InstVerIter(*this)->Size;
 510       else
 511          iDownloadSize -= P.InstVerIter(*this)->Size;
 512       return;
 513    }
 514
 515    // Removing
 516    if (Pkg->CurrentVer != 0 && P.InstallVer == 0)
 517    {
 518       if (Inverse == false)
 519          iUsrSize -= Pkg.CurrentVer()->InstalledSize;
 520       else
 521          iUsrSize += Pkg.CurrentVer()->InstalledSize;
 522       return;
 523    }
 524 }
 525                                                                         /*}}}*/
 526 // DepCache::AddStates - Add the package to the state counter           /*{{{*/
 527 // ---------------------------------------------------------------------
 528 /* This routine is tricky to use, you must make sure that it is never
 529    called twice for the same package. This means the Remove/Add section
 530    should be as short as possible and not encompass any code that will
 531    calld Remove/Add itself. Remember, dependencies can be circular so
 532    while processing a dep for Pkg it is possible that Add/Remove
 533    will be called on Pkg */
 534 void pkgDepCache::AddStates(const PkgIterator &Pkg,int Add)
 535 {
 536    StateCache &State = PkgState[Pkg->ID];
 537
 538    // The Package is broken (either minimal dep or policy dep)
 539    if ((State.DepState & DepInstMin) != DepInstMin)
 540       iBrokenCount += Add;
 541    if ((State.DepState & DepInstPolicy) != DepInstPolicy)
 542       iPolicyBrokenCount += Add;
 543
 544    // Bad state
 545    if (Pkg.State() != PkgIterator::NeedsNothing)
 546       iBadCount += Add;
 547
 548    // Not installed
 549    if (Pkg->CurrentVer == 0)
 550    {
 551       if (State.Mode == ModeDelete &&
 552           (State.iFlags | Purge) == Purge && Pkg.Purge() == false)
 553          iDelCount += Add;
 554
 555       if (State.Mode == ModeInstall)
 556          iInstCount += Add;
 557       return;
 558    }
 559
 560    // Installed, no upgrade
 561    if (State.Status == 0)
 562    {
 563       if (State.Mode == ModeDelete)
 564          iDelCount += Add;
 565       else
 566          if ((State.iFlags & ReInstall) == ReInstall)
 567             iInstCount += Add;
 568
 569       return;
 570    }
 571
 572    // Alll 3 are possible
 573    if (State.Mode == ModeDelete)
 574       iDelCount += Add;
 575    if (State.Mode == ModeKeep)
 576       iKeepCount += Add;
 577    if (State.Mode == ModeInstall)
 578       iInstCount += Add;
 579 }
 580                                                                         /*}}}*/
 581 // DepCache::BuildGroupOrs - Generate the Or group dep data             /*{{{*/
 582 // ---------------------------------------------------------------------
 583 /* The or group results are stored in the last item of the or group. This
 584    allows easy detection of the state of a whole or'd group. */
 585 void pkgDepCache::BuildGroupOrs(VerIterator const &V)
 586 {
 587    unsigned char Group = 0;
 588
 589    for (DepIterator D = V.DependsList(); D.end() != true; D++)
 590    {
 591       // Build the dependency state.
 592       unsigned char &State = DepState[D->ID];
 593
 594       /* Invert for Conflicts. We have to do this twice to get the
 595          right sense for a conflicts group */
 596       if (D->Type == Dep::Conflicts ||
 597           D->Type == Dep::DpkgBreaks ||
 598           D->Type == Dep::Obsoletes)
 599          State = ~State;
 600
 601       // Add to the group if we are within an or..
 602       State &= 0x7;
 603       Group |= State;
 604       State |= Group << 3;
 605       if ((D->CompareOp & Dep::Or) != Dep::Or)
 606          Group = 0;
 607
 608       // Invert for Conflicts
 609       if (D->Type == Dep::Conflicts ||
 610           D->Type == Dep::DpkgBreaks ||
 611           D->Type == Dep::Obsoletes)
 612          State = ~State;
 613    }
 614 }
 615                                                                         /*}}}*/
 616 // DepCache::VersionState - Perform a pass over a dependency list       /*{{{*/
 617 // ---------------------------------------------------------------------
 618 /* This is used to run over a dependency list and determine the dep
 619    state of the list, filtering it through both a Min check and a Policy
 620    check. The return result will have SetMin/SetPolicy low if a check
 621    fails. It uses the DepState cache for it's computations. */
 622 unsigned char pkgDepCache::VersionState(DepIterator D,unsigned char Check,
 623                                        unsigned char SetMin,
 624                                        unsigned char SetPolicy)
 625 {
 626    unsigned char Dep = 0xFF;
 627
 628    while (D.end() != true)
 629    {
 630       // Compute a single dependency element (glob or)
 631       DepIterator Start = D;
 632       unsigned char State = 0;
 633       for (bool LastOR = true; D.end() == false && LastOR == true; D++)
 634       {
 635          State |= DepState[D->ID];
 636          LastOR = (D->CompareOp & Dep::Or) == Dep::Or;
 637       }
 638
 639       // Minimum deps that must be satisfied to have a working package
 640       if (Start.IsCritical() == true)
 641          if ((State & Check) != Check)
 642             Dep &= ~SetMin;
 643
 644       // Policy deps that must be satisfied to install the package
 645       if (IsImportantDep(Start) == true &&
 646           (State & Check) != Check)
 647          Dep &= ~SetPolicy;
 648    }
 649
 650    return Dep;
 651 }
 652                                                                         /*}}}*/
 653 // DepCache::DependencyState - Compute the 3 results for a dep          /*{{{*/
 654 // ---------------------------------------------------------------------
 655 /* This is the main dependency computation bit. It computes the 3 main
 656    results for a dependencys, Now, Install and Candidate. Callers must
 657    invert the result if dealing with conflicts. */
 658 unsigned char pkgDepCache::DependencyState(DepIterator &D)
 659 {
 660    unsigned char State = 0;
 661
 662    if (CheckDep(D,NowVersion) == true)
 663       State |= DepNow;
 664    if (CheckDep(D,InstallVersion) == true)
 665       State |= DepInstall;
 666    if (CheckDep(D,CandidateVersion) == true)
 667       State |= DepCVer;
 668
 669    return State;
 670 }
 671                                                                         /*}}}*/
 672 // DepCache::UpdateVerState - Compute the Dep member of the state       /*{{{*/
 673 // ---------------------------------------------------------------------
 674 /* This determines the combined dependency representation of a package
 675    for its two states now and install. This is done by using the pre-generated
 676    dependency information. */
 677 void pkgDepCache::UpdateVerState(PkgIterator Pkg)
 678 {
 679    // Empty deps are always true
 680    StateCache &State = PkgState[Pkg->ID];
 681    State.DepState = 0xFF;
 682
 683    // Check the Current state
 684    if (Pkg->CurrentVer != 0)
 685    {
 686       DepIterator D = Pkg.CurrentVer().DependsList();
 687       State.DepState &= VersionState(D,DepNow,DepNowMin,DepNowPolicy);
 688    }
 689
 690    /* Check the candidate state. We do not compare against the whole as
 691       a candidate state but check the candidate version against the
 692       install states */
 693    if (State.CandidateVer != 0)
 694    {
 695       DepIterator D = State.CandidateVerIter(*this).DependsList();
 696       State.DepState &= VersionState(D,DepInstall,DepCandMin,DepCandPolicy);
 697    }
 698
 699    // Check target state which can only be current or installed
 700    if (State.InstallVer != 0)
 701    {
 702       DepIterator D = State.InstVerIter(*this).DependsList();
 703       State.DepState &= VersionState(D,DepInstall,DepInstMin,DepInstPolicy);
 704    }
 705 }
 706                                                                         /*}}}*/
 707 // DepCache::RemovePseudoInstalledPkg - MultiArch helper for Update()   /*{{{*/
 708 // ---------------------------------------------------------------------
 709 /* We "install" arch all packages for all archs if it is installed. Many
 710    of these will be broken. This method will look at these broken Pkg and
 711    "remove" it. */
 712 bool pkgDepCache::RemovePseudoInstalledPkg(PkgIterator &Pkg, std::set<unsigned long> &recheck) {
 713    if (unlikely(Pkg->CurrentVer == 0))
 714       return false;
 715
 716    VerIterator V = Pkg.CurrentVer();
 717    if (V->MultiArch != Version::All)
 718       return false;
 719
 720    // Never ever kill an "all" package - they have no dependency so they can't be broken
 721    if (strcmp(Pkg.Arch(),"all") == 0)
 722       return false;
 723
 724    unsigned char const CurDepState = VersionState(V.DependsList(),DepInstall,DepInstMin,DepInstPolicy);
 725    if ((CurDepState & DepInstMin) == DepInstMin) {
 726       // okay, the package isn't broken, but is the package also required?
 727       // If it has no real dependencies, no installed rdepends and doesn't
 728       // provide something of value, we will kill it as not required.
 729       // These pseudopackages have otherwise interesting effects if they get
 730       // a new dependency in a newer version…
 731       for (pkgCache::DepIterator D = V.DependsList();
 732            D.end() != true; ++D)
 733          if (D.IsCritical() == true && D.ParentPkg()->Group != Pkg->Group)
 734             return false;
 735       for (DepIterator D = Pkg.RevDependsList(); D.end() != true; ++D)
 736       {
 737          if (D.IsCritical() == false)
 738             continue;
 739          PkgIterator const P = D.ParentPkg();
 740          if (P->Group == Pkg->Group)
 741             continue;
 742          if (P->CurrentVer != 0)
 743             return false;
 744       }
 745       for (PrvIterator Prv = V.ProvidesList(); Prv.end() != true; Prv++)
 746          for (DepIterator d = Prv.ParentPkg().RevDependsList();
 747               d.end() != true; ++d)
 748          {
 749             PkgIterator const P = d.ParentPkg();
 750             if (P->CurrentVer != 0 &&
 751                 P->Group != Pkg->Group)
 752                return false;
 753          }
 754    }
 755
 756    // Dependencies for this arch all package are not statisfied
 757    // so we installed it only for our convenience: get right of it now.
 758    RemoveSizes(Pkg);
 759    RemoveStates(Pkg);
 760
 761    Pkg->CurrentVer = 0;
 762    PkgState[Pkg->ID].InstallVer = 0;
 763
 764    AddStates(Pkg);
 765    Update(Pkg);
 766    AddSizes(Pkg);
 767
 768    // After the remove previously satisfied pseudo pkg could be now
 769    // no longer satisfied, so we need to recheck the reverse dependencies
 770    for (DepIterator d = Pkg.RevDependsList(); d.end() != true; ++d)
 771    {
 772       PkgIterator const P = d.ParentPkg();
 773       if (P->CurrentVer != 0)
 774          recheck.insert(P.Index());
 775    }
 776
 777    for (DepIterator d = V.DependsList(); d.end() != true; ++d)
 778    {
 779       PkgIterator const P = d.TargetPkg();
 780       for (PrvIterator Prv = P.ProvidesList(); Prv.end() != true; ++Prv)
 781       {
 782          PkgIterator const O = Prv.OwnerPkg();
 783          if (O->CurrentVer != 0)
 784             recheck.insert(O.Index());
 785       }
 786
 787       if (P->CurrentVer != 0)
 788          recheck.insert(P.Index());
 789    }
 790
 791    for (PrvIterator Prv = V.ProvidesList(); Prv.end() != true; Prv++)
 792    {
 793       for (DepIterator d = Prv.ParentPkg().RevDependsList();
 794            d.end() != true; ++d)
 795       {
 796          PkgIterator const P = d.ParentPkg();
 797          if (P->CurrentVer == 0)
 798             continue;
 799
 800             recheck.insert(P.Index());
 801       }
 802    }
 803
 804
 805    return true;
 806 }
 807                                                                         /*}}}*/
 808 // DepCache::Update - Figure out all the state information              /*{{{*/
 809 // ---------------------------------------------------------------------
 810 /* This will figure out the state of all the packages and all the
 811    dependencies based on the current policy. */
 812 void pkgDepCache::Update(OpProgress *Prog)
 813 {
 814    iUsrSize = 0;
 815    iDownloadSize = 0;
 816    iDelCount = 0;
 817    iInstCount = 0;
 818    iKeepCount = 0;
 819    iBrokenCount = 0;
 820    iBadCount = 0;
 821
 822    std::set<unsigned long> recheck;
 823
 824    // Perform the depends pass
 825    int Done = 0;
 826    bool const checkMultiArch = APT::Configuration::getArchitectures().size() > 1;
 827    unsigned long killed = 0;
 828    for (PkgIterator I = PkgBegin(); I.end() != true; I++,Done++)
 829    {
 830       if (Prog != 0 && Done%20 == 0)
 831          Prog->Progress(Done);
 832       for (VerIterator V = I.VersionList(); V.end() != true; V++)
 833       {
 834          unsigned char Group = 0;
 835
 836          for (DepIterator D = V.DependsList(); D.end() != true; D++)
 837          {
 838             // Build the dependency state.
 839             unsigned char &State = DepState[D->ID];
 840             State = DependencyState(D);
 841
 842             // Add to the group if we are within an or..
 843             Group |= State;
 844             State |= Group << 3;
 845             if ((D->CompareOp & Dep::Or) != Dep::Or)
 846                Group = 0;
 847
 848             // Invert for Conflicts
 849             if (D->Type == Dep::Conflicts ||
 850                 D->Type == Dep::DpkgBreaks ||
 851                 D->Type == Dep::Obsoletes)
 852                State = ~State;
 853          }
 854       }
 855
 856       // Compute the package dependency state and size additions
 857       AddSizes(I);
 858       UpdateVerState(I);
 859       AddStates(I);
 860
 861       if (checkMultiArch != true || I->CurrentVer == 0)
 862          continue;
 863
 864       VerIterator const V = I.CurrentVer();
 865       if (V->MultiArch != Version::All)
 866          continue;
 867
 868       recheck.insert(I.Index());
 869       --Done; // no progress if we need to recheck the package
 870    }
 871
 872    if (checkMultiArch == true) {
 873       /* FIXME: recheck breaks proper progress reporting as we don't know
 874                 how many packages we need to recheck. To lower the effect
 875                 a bit we increase with a kill, but we should do something more clever… */
 876       while(recheck.empty() == false)
 877          for (std::set<unsigned long>::const_iterator p = recheck.begin();
 878              p != recheck.end();) {
 879             if (Prog != 0 && Done%20 == 0)
 880                Prog->Progress(Done);
 881             PkgIterator P = PkgIterator(*Cache, Cache->PkgP + *p);
 882             if (RemovePseudoInstalledPkg(P, recheck) == true) {
 883                ++killed;
 884                ++Done;
 885             }
 886             recheck.erase(p++);
 887          }
 888
 889       /* Okay, we have killed a great amount of pseudopackages -
 890          we have killed so many that we have now arch "all" packages
 891          without an installed pseudo package, but we NEED an installed
 892          pseudo package, so we will search now for a pseudo package
 893          we can install without breaking everything. */
 894       for (GrpIterator G = Cache->GrpBegin(); G.end() != true; ++G)
 895       {
 896          PkgIterator P = G.FindPkg("all");
 897          if (P.end() == true)
 898             continue;
 899          if (P->CurrentVer == 0)
 900             continue;
 901          bool installed = false;
 902          for (P = G.FindPkg("any"); P.end() != true; P = G.NextPkg(P))
 903          {
 904             if (strcmp(P.Arch(), "all") == 0)
 905                continue;
 906             if (P->CurrentVer == 0)
 907                continue;
 908             installed = true;
 909             break;
 910          }
 911          if (installed == false)
 912             recheck.insert(G.Index());
 913       }
 914
 915       while (recheck.empty() != true)
 916       {
 917          std::set<unsigned long>::const_iterator g = recheck.begin();
 918          unsigned long const G = *g;
 919          recheck.erase(g);
 920          if (unlikely(ReInstallPseudoForGroup(G, recheck) == false))
 921             _error->Warning(_("Internal error, group '%s' has no installable pseudo package"), GrpIterator(*Cache, Cache->GrpP + G).Name());
 922       }
 923    }
 924
 925    if (Prog != 0)
 926       Prog->Progress(Done);
 927
 928    readStateFile(Prog);
 929 }
 930                                                                         /*}}}*/
 931 // DepCache::ReInstallPseudoForGroup - MultiArch helper for Update()    /*{{{*/
 932 // ---------------------------------------------------------------------
 933 /* RemovePseudoInstalledPkg() is very successful. It even kills packages
 934    to an amount that no pseudo package is left, but we need a pseudo package
 935    for upgrading senarios so we need to reinstall one pseudopackage which
 936    doesn't break everything. Thankfully we can't have architecture depending
 937    negative dependencies so this problem is already eliminated */
 938 bool pkgDepCache::ReInstallPseudoForGroup(pkgCache::PkgIterator const &P, std::set<unsigned long> &recheck)
 939 {
 940    if (P->CurrentVer != 0)
 941       return true;
 942    // recursive call for packages which provide this package
 943    for (pkgCache::PrvIterator Prv = P.ProvidesList(); Prv.end() != true; ++Prv)
 944       ReInstallPseudoForGroup(Prv.OwnerPkg(), recheck);
 945    // check if we actually need to look at this group
 946    unsigned long const G = P->Group;
 947    std::set<unsigned long>::const_iterator Pi = recheck.find(G);
 948    if (Pi == recheck.end())
 949       return true;
 950    recheck.erase(Pi); // remove here, so we can't fall into an endless loop
 951    if (unlikely(ReInstallPseudoForGroup(G, recheck) == false))
 952    {
 953       recheck.insert(G);
 954       return false;
 955    }
 956    return true;
 957 }
 958 bool pkgDepCache::ReInstallPseudoForGroup(unsigned long const &G, std::set<unsigned long> &recheck)
 959 {
 960    std::vector<std::string> static const Archs = APT::Configuration::getArchitectures();
 961    pkgCache::GrpIterator Grp(*Cache, Cache->GrpP + G);
 962    if (unlikely(Grp.end() == true))
 963       return false;
 964    for (std::vector<std::string>::const_iterator a = Archs.begin();
 965         a != Archs.end(); ++a)
 966    {
 967       pkgCache::PkgIterator P = Grp.FindPkg(*a);
 968       if (P.end() == true)
 969          continue;
 970       pkgCache::VerIterator allV = Grp.FindPkg("all").CurrentVer();
 971       for (VerIterator V = P.VersionList(); V.end() != true; ++V)
 972       {
 973          // search for the same version as the all package
 974          if (allV->Hash != V->Hash || strcmp(allV.VerStr(),V.VerStr()) != 0)
 975             continue;
 976          unsigned char const CurDepState = VersionState(V.DependsList(),DepInstall,DepInstMin,DepInstPolicy);
 977          // If it is broken, try to install dependencies first before retry
 978          if ((CurDepState & DepInstMin) != DepInstMin)
 979          {
 980             for (pkgCache::DepIterator D = V.DependsList(); D.end() != true; ++D)
 981             {
 982                if (D->Type != pkgCache::Dep::PreDepends && D->Type != pkgCache::Dep::Depends)
 983                   continue;
 984                ReInstallPseudoForGroup(D.TargetPkg(), recheck);
 985             }
 986             unsigned char const CurDepState = VersionState(V.DependsList(),DepInstall,DepInstMin,DepInstPolicy);
 987             // if package ist still broken… try another arch
 988             if ((CurDepState & DepInstMin) != DepInstMin)
 989                break;
 990          }
 991          // dependencies satisfied: reinstall the package
 992          RemoveSizes(P);
 993          RemoveStates(P);
 994          P->CurrentVer = V.Index();
 995          PkgState[P->ID].InstallVer = V;
 996          AddStates(P);
 997          Update(P);
 998          AddSizes(P);
 999          return true;
1000       }
1001    }
1002    return false;
1003 }
1004                                                                         /*}}}*/
1005 // DepCache::Update - Update the deps list of a package                 /*{{{*/
1006 // ---------------------------------------------------------------------
1007 /* This is a helper for update that only does the dep portion of the scan.
1008    It is mainly meant to scan reverse dependencies. */
1009 void pkgDepCache::Update(DepIterator D)
1010 {
1011    // Update the reverse deps
1012    for (;D.end() != true; D++)
1013    {
1014       unsigned char &State = DepState[D->ID];
1015       State = DependencyState(D);
1016
1017       // Invert for Conflicts
1018       if (D->Type == Dep::Conflicts ||
1019           D->Type == Dep::DpkgBreaks ||
1020           D->Type == Dep::Obsoletes)
1021          State = ~State;
1022
1023       RemoveStates(D.ParentPkg());
1024       BuildGroupOrs(D.ParentVer());
1025       UpdateVerState(D.ParentPkg());
1026       AddStates(D.ParentPkg());
1027    }
1028 }
1029                                                                         /*}}}*/
1030 // DepCache::Update - Update the related deps of a package              /*{{{*/
1031 // ---------------------------------------------------------------------
1032 /* This is called whenever the state of a package changes. It updates
1033    all cached dependencies related to this package. */
1034 void pkgDepCache::Update(PkgIterator const &Pkg)
1035 {
1036    // Recompute the dep of the package
1037    RemoveStates(Pkg);
1038    UpdateVerState(Pkg);
1039    AddStates(Pkg);
1040
1041    // Update the reverse deps
1042    Update(Pkg.RevDependsList());
1043
1044    // Update the provides map for the current ver
1045    if (Pkg->CurrentVer != 0)
1046       for (PrvIterator P = Pkg.CurrentVer().ProvidesList();
1047            P.end() != true; P++)
1048          Update(P.ParentPkg().RevDependsList());
1049
1050    // Update the provides map for the candidate ver
1051    if (PkgState[Pkg->ID].CandidateVer != 0)
1052       for (PrvIterator P = PkgState[Pkg->ID].CandidateVerIter(*this).ProvidesList();
1053            P.end() != true; P++)
1054          Update(P.ParentPkg().RevDependsList());
1055 }
1056                                                                         /*}}}*/
1057 // DepCache::MarkKeep - Put the package in the keep state               /*{{{*/
1058 // ---------------------------------------------------------------------
1059 /* */
1060 void pkgDepCache::MarkKeep(PkgIterator const &Pkg, bool Soft, bool FromUser,
1061                            unsigned long Depth)
1062 {
1063    // Simplifies other routines.
1064    if (Pkg.end() == true)
1065       return;
1066
1067    /* Reject an attempt to keep a non-source broken installed package, those
1068       must be upgraded */
1069    if (Pkg.State() == PkgIterator::NeedsUnpack &&
1070        Pkg.CurrentVer().Downloadable() == false)
1071       return;
1072
1073    /** \todo Can this be moved later in the method? */
1074    ActionGroup group(*this);
1075
1076    /* We changed the soft state all the time so the UI is a bit nicer
1077       to use */
1078    StateCache &P = PkgState[Pkg->ID];
1079    if (Soft == true)
1080       P.iFlags |= AutoKept;
1081    else
1082       P.iFlags &= ~AutoKept;
1083
1084    // Check that it is not already kept
1085    if (P.Mode == ModeKeep)
1086       return;
1087
1088    // We dont even try to keep virtual packages..
1089    if (Pkg->VersionList == 0)
1090       return;
1091 #if 0 // reseting the autoflag here means we lose the
1092       // auto-mark information if a user selects a package for removal
1093       // but changes  his mind then and sets it for keep again
1094       // - this makes sense as default when all Garbage dependencies
1095       //   are automatically marked for removal (as aptitude does).
1096       //   setting a package for keep then makes it no longer autoinstalled
1097       //   for all other use-case this action is rather suprising
1098    if(FromUser && !P.Marked)
1099      P.Flags &= ~Flag::Auto;
1100 #endif
1101
1102    if (DebugMarker == true)
1103       std::clog << OutputInDepth(Depth) << "MarkKeep " << Pkg << " FU=" << FromUser << std::endl;
1104
1105    RemoveSizes(Pkg);
1106    RemoveStates(Pkg);
1107
1108    P.Mode = ModeKeep;
1109    if (Pkg->CurrentVer == 0)
1110       P.InstallVer = 0;
1111    else
1112       P.InstallVer = Pkg.CurrentVer();
1113
1114    AddStates(Pkg);
1115
1116    Update(Pkg);
1117
1118    AddSizes(Pkg);
1119 }
1120                                                                         /*}}}*/
1121 // DepCache::MarkDelete - Put the package in the delete state           /*{{{*/
1122 // ---------------------------------------------------------------------
1123 /* */
1124 void pkgDepCache::MarkDelete(PkgIterator const &Pkg, bool rPurge,
1125                              unsigned long Depth, bool FromUser)
1126 {
1127    // Simplifies other routines.
1128    if (Pkg.end() == true)
1129       return;
1130
1131    ActionGroup group(*this);
1132
1133    // Check that it is not already marked for delete
1134    StateCache &P = PkgState[Pkg->ID];
1135    P.iFlags &= ~(AutoKept | Purge);
1136    if (rPurge == true)
1137       P.iFlags |= Purge;
1138
1139    if ((P.Mode == ModeDelete || P.InstallVer == 0) &&
1140        (Pkg.Purge() == true || rPurge == false))
1141       return;
1142
1143    // We dont even try to delete virtual packages..
1144    if (Pkg->VersionList == 0)
1145       return;
1146
1147    // check if we are allowed to install the package
1148    if (IsDeleteOk(Pkg,rPurge,Depth,FromUser) == false)
1149       return;
1150
1151    if (DebugMarker == true)
1152       std::clog << OutputInDepth(Depth) << "MarkDelete " << Pkg << " FU=" << FromUser << std::endl;
1153
1154    RemoveSizes(Pkg);
1155    RemoveStates(Pkg);
1156
1157    if (Pkg->CurrentVer == 0 && (Pkg.Purge() == true || rPurge == false))
1158       P.Mode = ModeKeep;
1159    else
1160       P.Mode = ModeDelete;
1161    P.InstallVer = 0;
1162
1163    AddStates(Pkg);
1164    Update(Pkg);
1165    AddSizes(Pkg);
1166
1167    // if we remove the pseudo package, we also need to remove the "real"
1168    if (Pkg->CurrentVer != 0 && Pkg.CurrentVer().Pseudo() == true)
1169       MarkDelete(Pkg.Group().FindPkg("all"), rPurge, Depth+1, FromUser);
1170 }
1171                                                                         /*}}}*/
1172 // DepCache::IsDeleteOk - check if it is ok to remove this package      /*{{{*/
1173 // ---------------------------------------------------------------------
1174 /* The default implementation just honors dpkg hold
1175    But an application using this library can override this method
1176    to control the MarkDelete behaviour */
1177 bool pkgDepCache::IsDeleteOk(PkgIterator const &Pkg,bool rPurge,
1178                               unsigned long Depth, bool FromUser)
1179 {
1180    if (FromUser == false && Pkg->SelectedState == pkgCache::State::Hold && _config->FindB("APT::Ignore-Hold",false) == false)
1181    {
1182       if (DebugMarker == true)
1183          std::clog << OutputInDepth(Depth) << "Hold prevents MarkDelete of " << Pkg << " FU=" << FromUser << std::endl;
1184       return false;
1185    }
1186    return true;
1187 }
1188                                                                         /*}}}*/
1189 // DepCache::MarkInstall - Put the package in the install state         /*{{{*/
1190 // ---------------------------------------------------------------------
1191 /* */
1192 void pkgDepCache::MarkInstall(PkgIterator const &Pkg,bool AutoInst,
1193                               unsigned long Depth, bool FromUser,
1194                               bool ForceImportantDeps)
1195 {
1196    if (Depth > 100)
1197       return;
1198
1199    // Simplifies other routines.
1200    if (Pkg.end() == true)
1201       return;
1202
1203    ActionGroup group(*this);
1204
1205    /* Check that it is not already marked for install and that it can be
1206       installed */
1207    StateCache &P = PkgState[Pkg->ID];
1208    P.iFlags &= ~AutoKept;
1209    if ((P.InstPolicyBroken() == false && P.InstBroken() == false) &&
1210        (P.Mode == ModeInstall ||
1211         P.CandidateVer == (Version *)Pkg.CurrentVer()))
1212    {
1213       if (P.CandidateVer == (Version *)Pkg.CurrentVer() && P.InstallVer == 0)
1214          MarkKeep(Pkg, false, FromUser, Depth+1);
1215       return;
1216    }
1217
1218    // See if there is even any possible instalation candidate
1219    if (P.CandidateVer == 0)
1220       return;
1221    // We dont even try to install virtual packages..
1222    if (Pkg->VersionList == 0)
1223       return;
1224
1225    // check if we are allowed to install the package
1226    if (IsInstallOk(Pkg,AutoInst,Depth,FromUser) == false)
1227       return;
1228
1229    /* Target the candidate version and remove the autoflag. We reset the
1230       autoflag below if this was called recursively. Otherwise the user
1231       should have the ability to de-auto a package by changing its state */
1232    RemoveSizes(Pkg);
1233    RemoveStates(Pkg);
1234
1235    P.Mode = ModeInstall;
1236    P.InstallVer = P.CandidateVer;
1237
1238    if(FromUser)
1239      {
1240        // Set it to manual if it's a new install or cancelling the
1241        // removal of a garbage package.
1242        if(P.Status == 2 || (!Pkg.CurrentVer().end() && !P.Marked))
1243          P.Flags &= ~Flag::Auto;
1244      }
1245    else
1246      {
1247        // Set it to auto if this is a new install.
1248        if(P.Status == 2)
1249          P.Flags |= Flag::Auto;
1250      }
1251    if (P.CandidateVer == (Version *)Pkg.CurrentVer())
1252       P.Mode = ModeKeep;
1253
1254    AddStates(Pkg);
1255    Update(Pkg);
1256    AddSizes(Pkg);
1257
1258    if (AutoInst == false)
1259       return;
1260
1261    if (DebugMarker == true)
1262       std::clog << OutputInDepth(Depth) << "MarkInstall " << Pkg << " FU=" << FromUser << std::endl;
1263
1264    DepIterator Dep = P.InstVerIter(*this).DependsList();
1265    for (; Dep.end() != true;)
1266    {
1267       // Grok or groups
1268       DepIterator Start = Dep;
1269       bool Result = true;
1270       unsigned Ors = 0;
1271       for (bool LastOR = true; Dep.end() == false && LastOR == true; Dep++,Ors++)
1272       {
1273          LastOR = (Dep->CompareOp & Dep::Or) == Dep::Or;
1274
1275          if ((DepState[Dep->ID] & DepInstall) == DepInstall)
1276             Result = false;
1277       }
1278
1279       // Dep is satisfied okay.
1280       if (Result == false)
1281          continue;
1282
1283       /* Check if this dep should be consider for install. If it is a user
1284          defined important dep and we are installed a new package then
1285          it will be installed. Otherwise we only check for important
1286          deps that have changed from the installed version
1287       */
1288       if (IsImportantDep(Start) == false)
1289          continue;
1290
1291       /* Check if any ImportantDep() (but not Critical) were added
1292        * since we installed the package.  Also check for deps that
1293        * were satisfied in the past: for instance, if a version
1294        * restriction in a Recommends was tightened, upgrading the
1295        * package should follow that Recommends rather than causing the
1296        * dependency to be removed. (bug #470115)
1297        */
1298       bool isNewImportantDep = false;
1299       bool isPreviouslySatisfiedImportantDep = false;
1300       if(!ForceImportantDeps && !Start.IsCritical())
1301       {
1302          bool found=false;
1303          VerIterator instVer = Pkg.CurrentVer();
1304          if(!instVer.end())
1305          {
1306            for (DepIterator D = instVer.DependsList(); D.end() != true; D++)
1307              {
1308                //FIXME: deal better with or-groups(?)
1309                DepIterator LocalStart = D;
1310
1311                if(IsImportantDep(D) && !D.IsCritical() &&
1312                   Start.TargetPkg() == D.TargetPkg())
1313                  {
1314                    if(!isPreviouslySatisfiedImportantDep)
1315                      {
1316                        DepIterator D2 = D;
1317                        while((D2->CompareOp & Dep::Or) != 0)
1318                          ++D2;
1319
1320                        isPreviouslySatisfiedImportantDep =
1321                          (((*this)[D2] & DepGNow) != 0);
1322                      }
1323
1324                    found=true;
1325                  }
1326              }
1327             // this is a new dep if it was not found to be already
1328             // a important dep of the installed pacakge
1329             isNewImportantDep = !found;
1330          }
1331       }
1332       if(isNewImportantDep)
1333          if(DebugAutoInstall == true)
1334             std::clog << OutputInDepth(Depth) << "new important dependency: "
1335                       << Start.TargetPkg().Name() << std::endl;
1336       if(isPreviouslySatisfiedImportantDep)
1337         if(DebugAutoInstall == true)
1338           std::clog << OutputInDepth(Depth) << "previously satisfied important dependency on "
1339                     << Start.TargetPkg().Name() << std::endl;
1340
1341       // skip important deps if the package is already installed
1342       if (Pkg->CurrentVer != 0 && Start.IsCritical() == false
1343           && !isNewImportantDep && !isPreviouslySatisfiedImportantDep
1344           && !ForceImportantDeps)
1345          continue;
1346
1347       /* If we are in an or group locate the first or that can
1348          succeed. We have already cached this.. */
1349       for (; Ors > 1 && (DepState[Start->ID] & DepCVer) != DepCVer; Ors--)
1350          Start++;
1351
1352       /* This bit is for processing the possibilty of an install/upgrade
1353          fixing the problem */
1354       SPtrArray<Version *> List = Start.AllTargets();
1355       if (Start->Type != Dep::DpkgBreaks &&
1356           (DepState[Start->ID] & DepCVer) == DepCVer)
1357       {
1358          // Right, find the best version to install..
1359          Version **Cur = List;
1360          PkgIterator P = Start.TargetPkg();
1361          PkgIterator InstPkg(*Cache,0);
1362
1363          // See if there are direct matches (at the start of the list)
1364          for (; *Cur != 0 && (*Cur)->ParentPkg == P.Index(); Cur++)
1365          {
1366             PkgIterator Pkg(*Cache,Cache->PkgP + (*Cur)->ParentPkg);
1367             if (PkgState[Pkg->ID].CandidateVer != *Cur)
1368                continue;
1369             InstPkg = Pkg;
1370             break;
1371          }
1372
1373          // Select the highest priority providing package
1374          if (InstPkg.end() == true)
1375          {
1376             pkgPrioSortList(*Cache,Cur);
1377             for (; *Cur != 0; Cur++)
1378             {
1379                PkgIterator Pkg(*Cache,Cache->PkgP + (*Cur)->ParentPkg);
1380                if (PkgState[Pkg->ID].CandidateVer != *Cur)
1381                   continue;
1382                InstPkg = Pkg;
1383                break;
1384             }
1385          }
1386
1387          if (InstPkg.end() == false)
1388          {
1389             if(DebugAutoInstall == true)
1390                std::clog << OutputInDepth(Depth) << "Installing " << InstPkg.Name()
1391                          << " as " << Start.DepType() << " of " << Pkg.Name()
1392                          << std::endl;
1393             // now check if we should consider it a automatic dependency or not
1394             if(Pkg.Section() && ConfigValueInSubTree("APT::Never-MarkAuto-Sections", Pkg.Section()))
1395             {
1396                if(DebugAutoInstall == true)
1397                   std::clog << OutputInDepth(Depth) << "Setting NOT as auto-installed (direct "
1398                             << Start.DepType() << " of pkg in APT::Never-MarkAuto-Sections)" << std::endl;
1399                MarkInstall(InstPkg,true,Depth + 1, true);
1400             }
1401             else
1402             {
1403                // mark automatic dependency
1404                MarkInstall(InstPkg,true,Depth + 1, false, ForceImportantDeps);
1405                // Set the autoflag, after MarkInstall because MarkInstall unsets it
1406                if (P->CurrentVer == 0)
1407                   PkgState[InstPkg->ID].Flags |= Flag::Auto;
1408             }
1409          }
1410          continue;
1411       }
1412
1413       /* For conflicts we just de-install the package and mark as auto,
1414          Conflicts may not have or groups.  For dpkg's Breaks we try to
1415          upgrade the package. */
1416       if (Start->Type == Dep::Conflicts || Start->Type == Dep::Obsoletes ||
1417           Start->Type == Dep::DpkgBreaks)
1418       {
1419          for (Version **I = List; *I != 0; I++)
1420          {
1421             VerIterator Ver(*this,*I);
1422             PkgIterator Pkg = Ver.ParentPkg();
1423
1424             if (Start->Type != Dep::DpkgBreaks)
1425                MarkDelete(Pkg,false,Depth + 1, false);
1426             else if (PkgState[Pkg->ID].CandidateVer != *I)
1427                MarkInstall(Pkg,true,Depth + 1, false, ForceImportantDeps);
1428          }
1429          continue;
1430       }
1431    }
1432 }
1433                                                                         /*}}}*/
1434 // DepCache::IsInstallOk - check if it is ok to install this package    /*{{{*/
1435 // ---------------------------------------------------------------------
1436 /* The default implementation just honors dpkg hold
1437    But an application using this library can override this method
1438    to control the MarkInstall behaviour */
1439 bool pkgDepCache::IsInstallOk(PkgIterator const &Pkg,bool AutoInst,
1440                               unsigned long Depth, bool FromUser)
1441 {
1442    if (FromUser == false && Pkg->SelectedState == pkgCache::State::Hold && _config->FindB("APT::Ignore-Hold",false) == false)
1443    {
1444       if (DebugMarker == true)
1445          std::clog << OutputInDepth(Depth) << "Hold prevents MarkInstall of " << Pkg << " FU=" << FromUser << std::endl;
1446       return false;
1447    }
1448    return true;
1449 }
1450                                                                         /*}}}*/
1451 // DepCache::SetReInstall - Set the reinstallation flag                 /*{{{*/
1452 // ---------------------------------------------------------------------
1453 /* */
1454 void pkgDepCache::SetReInstall(PkgIterator const &Pkg,bool To)
1455 {
1456    ActionGroup group(*this);
1457
1458    RemoveSizes(Pkg);
1459    RemoveStates(Pkg);
1460
1461    StateCache &P = PkgState[Pkg->ID];
1462    if (To == true)
1463       P.iFlags |= ReInstall;
1464    else
1465       P.iFlags &= ~ReInstall;
1466
1467    AddStates(Pkg);
1468    AddSizes(Pkg);
1469 }
1470                                                                         /*}}}*/
1471 // DepCache::SetCandidateVersion - Change the candidate version         /*{{{*/
1472 // ---------------------------------------------------------------------
1473 /* */
1474 void pkgDepCache::SetCandidateVersion(VerIterator TargetVer)
1475 {
1476    ActionGroup group(*this);
1477
1478    pkgCache::PkgIterator Pkg = TargetVer.ParentPkg();
1479    StateCache &P = PkgState[Pkg->ID];
1480
1481    RemoveSizes(Pkg);
1482    RemoveStates(Pkg);
1483
1484    if (P.CandidateVer == P.InstallVer)
1485       P.InstallVer = (Version *)TargetVer;
1486    P.CandidateVer = (Version *)TargetVer;
1487    P.Update(Pkg,*this);
1488
1489    AddStates(Pkg);
1490    Update(Pkg);
1491    AddSizes(Pkg);
1492 }
1493
1494 void pkgDepCache::MarkAuto(const PkgIterator &Pkg, bool Auto)
1495 {
1496   StateCache &state = PkgState[Pkg->ID];
1497
1498   ActionGroup group(*this);
1499
1500   if(Auto)
1501     state.Flags |= Flag::Auto;
1502   else
1503     state.Flags &= ~Flag::Auto;
1504 }
1505                                                                         /*}}}*/
1506 // StateCache::Update - Compute the various static display things       /*{{{*/
1507 // ---------------------------------------------------------------------
1508 /* This is called whenever the Candidate version changes. */
1509 void pkgDepCache::StateCache::Update(PkgIterator Pkg,pkgCache &Cache)
1510 {
1511    // Some info
1512    VerIterator Ver = CandidateVerIter(Cache);
1513
1514    // Use a null string or the version string
1515    if (Ver.end() == true)
1516       CandVersion = "";
1517    else
1518       CandVersion = Ver.VerStr();
1519
1520    // Find the current version
1521    CurVersion = "";
1522    if (Pkg->CurrentVer != 0)
1523       CurVersion = Pkg.CurrentVer().VerStr();
1524
1525    // Strip off the epochs for display
1526    CurVersion = StripEpoch(CurVersion);
1527    CandVersion = StripEpoch(CandVersion);
1528
1529    // Figure out if its up or down or equal
1530    Status = Ver.CompareVer(Pkg.CurrentVer());
1531    if (Pkg->CurrentVer == 0 || Pkg->VersionList == 0 || CandidateVer == 0)
1532      Status = 2;
1533 }
1534                                                                         /*}}}*/
1535 // StateCache::StripEpoch - Remove the epoch specifier from the version /*{{{*/
1536 // ---------------------------------------------------------------------
1537 /* */
1538 const char *pkgDepCache::StateCache::StripEpoch(const char *Ver)
1539 {
1540    if (Ver == 0)
1541       return 0;
1542
1543    // Strip any epoch
1544    for (const char *I = Ver; *I != 0; I++)
1545       if (*I == ':')
1546          return I + 1;
1547    return Ver;
1548 }
1549                                                                         /*}}}*/
1550 // Policy::GetCandidateVer - Returns the Candidate install version      /*{{{*/
1551 // ---------------------------------------------------------------------
1552 /* The default just returns the highest available version that is not
1553    a source and automatic. */
1554 pkgCache::VerIterator pkgDepCache::Policy::GetCandidateVer(PkgIterator Pkg)
1555 {
1556    /* Not source/not automatic versions cannot be a candidate version
1557       unless they are already installed */
1558    VerIterator Last(*(pkgCache *)this,0);
1559
1560    for (VerIterator I = Pkg.VersionList(); I.end() == false; I++)
1561    {
1562       if (Pkg.CurrentVer() == I)
1563          return I;
1564
1565       for (VerFileIterator J = I.FileList(); J.end() == false; J++)
1566       {
1567          if ((J.File()->Flags & Flag::NotSource) != 0)
1568             continue;
1569
1570          /* Stash the highest version of a not-automatic source, we use it
1571             if there is nothing better */
1572          if ((J.File()->Flags & Flag::NotAutomatic) != 0)
1573          {
1574             if (Last.end() == true)
1575                Last = I;
1576             continue;
1577          }
1578
1579          return I;
1580       }
1581    }
1582
1583    return Last;
1584 }
1585                                                                         /*}}}*/
1586 // Policy::IsImportantDep - True if the dependency is important         /*{{{*/
1587 // ---------------------------------------------------------------------
1588 /* */
1589 bool pkgDepCache::Policy::IsImportantDep(DepIterator Dep)
1590 {
1591    if(Dep.IsCritical())
1592       return true;
1593    else if(Dep->Type == pkgCache::Dep::Recommends)
1594    {
1595       if ( _config->FindB("APT::Install-Recommends", false))
1596          return true;
1597       // we suport a special mode to only install-recommends for certain
1598       // sections
1599       // FIXME: this is a meant as a temporarly solution until the
1600       //        recommends are cleaned up
1601       const char *sec = Dep.ParentVer().Section();
1602       if (sec && ConfigValueInSubTree("APT::Install-Recommends-Sections", sec))
1603          return true;
1604    }
1605    else if(Dep->Type == pkgCache::Dep::Suggests)
1606      return _config->FindB("APT::Install-Suggests", false);
1607
1608    return false;
1609 }
1610                                                                         /*}}}*/
1611 pkgDepCache::DefaultRootSetFunc::DefaultRootSetFunc()                   /*{{{*/
1612   : constructedSuccessfully(false)
1613 {
1614   Configuration::Item const *Opts;
1615   Opts = _config->Tree("APT::NeverAutoRemove");
1616   if (Opts != 0 && Opts->Child != 0)
1617     {
1618       Opts = Opts->Child;
1619       for (; Opts != 0; Opts = Opts->Next)
1620         {
1621           if (Opts->Value.empty() == true)
1622             continue;
1623
1624           regex_t *p = new regex_t;
1625           if(regcomp(p,Opts->Value.c_str(),
1626                      REG_EXTENDED | REG_ICASE | REG_NOSUB) != 0)
1627             {
1628               regfree(p);
1629               delete p;
1630               _error->Error("Regex compilation error for APT::NeverAutoRemove");
1631               return;
1632             }
1633
1634           rootSetRegexp.push_back(p);
1635         }
1636     }
1637
1638   constructedSuccessfully = true;
1639 }
1640                                                                         /*}}}*/
1641 pkgDepCache::DefaultRootSetFunc::~DefaultRootSetFunc()                  /*{{{*/
1642 {
1643   for(unsigned int i = 0; i < rootSetRegexp.size(); i++)
1644     {
1645       regfree(rootSetRegexp[i]);
1646       delete rootSetRegexp[i];
1647     }
1648 }
1649                                                                         /*}}}*/
1650 bool pkgDepCache::DefaultRootSetFunc::InRootSet(const pkgCache::PkgIterator &pkg) /*{{{*/
1651 {
1652    for(unsigned int i = 0; i < rootSetRegexp.size(); i++)
1653       if (regexec(rootSetRegexp[i], pkg.Name(), 0, 0, 0) == 0)
1654          return true;
1655
1656    return false;
1657 }
1658                                                                         /*}}}*/
1659 pkgDepCache::InRootSetFunc *pkgDepCache::GetRootSetFunc()               /*{{{*/
1660 {
1661   DefaultRootSetFunc *f = new DefaultRootSetFunc;
1662   if(f->wasConstructedSuccessfully())
1663     return f;
1664   else
1665     {
1666       delete f;
1667       return NULL;
1668     }
1669 }
1670                                                                         /*}}}*/
1671 bool pkgDepCache::MarkFollowsRecommends()
1672 {
1673   return _config->FindB("APT::AutoRemove::RecommendsImportant", true);
1674 }
1675
1676 bool pkgDepCache::MarkFollowsSuggests()
1677 {
1678   return _config->FindB("APT::AutoRemove::SuggestsImportant", false);
1679 }
1680
1681 // pkgDepCache::MarkRequired - the main mark algorithm                  /*{{{*/
1682 bool pkgDepCache::MarkRequired(InRootSetFunc &userFunc)
1683 {
1684    bool follow_recommends;
1685    bool follow_suggests;
1686    bool debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
1687
1688    // init the states
1689    for(PkgIterator p = PkgBegin(); !p.end(); ++p)
1690    {
1691       PkgState[p->ID].Marked  = false;
1692       PkgState[p->ID].Garbage = false;
1693
1694       // debug output
1695       if(debug_autoremove && PkgState[p->ID].Flags & Flag::Auto)
1696          std::clog << "AutoDep: " << p.FullName() << std::endl;
1697    }
1698
1699    // init vars
1700    follow_recommends = MarkFollowsRecommends();
1701    follow_suggests   = MarkFollowsSuggests();
1702
1703
1704
1705    // do the mark part, this is the core bit of the algorithm
1706    for(PkgIterator p = PkgBegin(); !p.end(); ++p)
1707    {
1708       if(!(PkgState[p->ID].Flags & Flag::Auto) ||
1709           (p->Flags & Flag::Essential) ||
1710           userFunc.InRootSet(p) ||
1711           // be nice even then a required package violates the policy (#583517)
1712           // and do the full mark process also for required packages
1713           (p.CurrentVer().end() != true &&
1714            p.CurrentVer()->Priority == pkgCache::State::Required))
1715       {
1716          // the package is installed (and set to keep)
1717          if(PkgState[p->ID].Keep() && !p.CurrentVer().end())
1718             MarkPackage(p, p.CurrentVer(),
1719                         follow_recommends, follow_suggests);
1720          // the package is to be installed
1721          else if(PkgState[p->ID].Install())
1722             MarkPackage(p, PkgState[p->ID].InstVerIter(*this),
1723                         follow_recommends, follow_suggests);
1724       }
1725    }
1726
1727    return true;
1728 }
1729                                                                         /*}}}*/
1730 // MarkPackage - mark a single package in Mark-and-Sweep                /*{{{*/
1731 void pkgDepCache::MarkPackage(const pkgCache::PkgIterator &pkg,
1732                               const pkgCache::VerIterator &ver,
1733                               bool const &follow_recommends,
1734                               bool const &follow_suggests)
1735 {
1736    pkgDepCache::StateCache &state = PkgState[pkg->ID];
1737
1738    // if we are marked already we are done
1739    if(state.Marked)
1740       return;
1741
1742    VerIterator const currver = pkg.CurrentVer();
1743    VerIterator const candver = state.CandidateVerIter(*this);
1744    VerIterator const instver = state.InstVerIter(*this);
1745
1746 #if 0
1747    // If a package was garbage-collected but is now being marked, we
1748    // should re-select it
1749    // For cases when a pkg is set to upgrade and this trigger the
1750    // removal of a no-longer used dependency.  if the pkg is set to
1751    // keep again later it will result in broken deps
1752    if(state.Delete() && state.RemoveReason = Unused)
1753    {
1754       if(ver==candver)
1755          mark_install(pkg, false, false, NULL);
1756       else if(ver==pkg.CurrentVer())
1757          MarkKeep(pkg, false, false);
1758
1759       instver=state.InstVerIter(*this);
1760    }
1761 #endif
1762
1763    // For packages that are not going to be removed, ignore versions
1764    // other than the InstVer.  For packages that are going to be
1765    // removed, ignore versions other than the current version.
1766    if(!(ver == instver && !instver.end()) &&
1767       !(ver == currver && instver.end() && !ver.end()))
1768       return;
1769
1770    bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove", false);
1771
1772    if(debug_autoremove)
1773      {
1774        std::clog << "Marking: " << pkg.FullName();
1775        if(!ver.end())
1776          std::clog << " " << ver.VerStr();
1777        if(!currver.end())
1778          std::clog << ", Curr=" << currver.VerStr();
1779        if(!instver.end())
1780          std::clog << ", Inst=" << instver.VerStr();
1781        std::clog << std::endl;
1782      }
1783
1784    state.Marked=true;
1785
1786    if(ver.end() == true)
1787       return;
1788
1789    // If the version belongs to a Multi-Arch all package
1790    // we will mark all others in this Group with this version also
1791    if (ver->MultiArch == pkgCache::Version::All &&
1792         strcmp(ver.Arch(true), "all") == 0)
1793    {
1794       GrpIterator G = pkg.Group();
1795       const char* const VerStr = ver.VerStr();
1796       for (PkgIterator P = G.FindPkg("any");
1797            P.end() != true; P = G.NextPkg(P))
1798       {
1799          for (VerIterator V = P.VersionList();
1800               V.end() != true; ++V)
1801          {
1802             if (ver->Hash != V->Hash ||
1803                 strcmp(VerStr, V.VerStr()) != 0)
1804                continue;
1805             MarkPackage(P, V, follow_recommends, follow_suggests);
1806             break;
1807          }
1808       }
1809    }
1810
1811      for(DepIterator d = ver.DependsList(); !d.end(); ++d)
1812      {
1813         if(d->Type == Dep::Depends ||
1814            d->Type == Dep::PreDepends ||
1815            (follow_recommends &&
1816             d->Type == Dep::Recommends) ||
1817            (follow_suggests &&
1818             d->Type == Dep::Suggests))
1819         {
1820            // Try all versions of this package.
1821            for(VerIterator V = d.TargetPkg().VersionList();
1822                !V.end(); ++V)
1823            {
1824               if(_system->VS->CheckDep(V.VerStr(), d->CompareOp, d.TargetVer()))
1825               {
1826                 if(debug_autoremove)
1827                   {
1828                     std::clog << "Following dep: " << d.ParentPkg().FullName()
1829                               << " " << d.ParentVer().VerStr() << " "
1830                               << d.DepType() << " " << d.TargetPkg().FullName();
1831                     if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
1832                       {
1833                         std::clog << " (" << d.CompType() << " "
1834                                   << d.TargetVer() << ")";
1835                       }
1836                     std::clog << std::endl;
1837                   }
1838                  MarkPackage(V.ParentPkg(), V,
1839                              follow_recommends, follow_suggests);
1840               }
1841            }
1842            // Now try virtual packages
1843            for(PrvIterator prv=d.TargetPkg().ProvidesList();
1844                !prv.end(); ++prv)
1845            {
1846               if(_system->VS->CheckDep(prv.ProvideVersion(), d->CompareOp,
1847                                        d.TargetVer()))
1848               {
1849                 if(debug_autoremove)
1850                   {
1851                     std::clog << "Following dep: " << d.ParentPkg().FullName() << " "
1852                               << d.ParentVer().VerStr() << " "
1853                               << d.DepType() << " " << d.TargetPkg().FullName() << " ";
1854                     if((d->CompareOp & ~pkgCache::Dep::Or) != pkgCache::Dep::NoOp)
1855                       {
1856                         std::clog << " (" << d.CompType() << " "
1857                                   << d.TargetVer() << ")";
1858                       }
1859                     std::clog << ", provided by "
1860                               << prv.OwnerPkg().FullName() << " "
1861                               << prv.OwnerVer().VerStr()
1862                               << std::endl;
1863                   }
1864
1865                  MarkPackage(prv.OwnerPkg(), prv.OwnerVer(),
1866                              follow_recommends, follow_suggests);
1867               }
1868            }
1869         }
1870      }
1871 }
1872                                                                         /*}}}*/
1873 bool pkgDepCache::Sweep()                                               /*{{{*/
1874 {
1875    bool debug_autoremove = _config->FindB("Debug::pkgAutoRemove",false);
1876
1877    // do the sweep
1878    for(PkgIterator p=PkgBegin(); !p.end(); ++p)
1879    {
1880      StateCache &state=PkgState[p->ID];
1881
1882      // skip required packages
1883      if (!p.CurrentVer().end() &&
1884          (p.CurrentVer()->Priority == pkgCache::State::Required))
1885         continue;
1886
1887      // if it is not marked and it is installed, it's garbage
1888      if(!state.Marked && (!p.CurrentVer().end() || state.Install()))
1889      {
1890         state.Garbage=true;
1891         if(debug_autoremove)
1892            std::clog << "Garbage: " << p.FullName() << std::endl;
1893      }
1894   }
1895
1896    return true;
1897 }
1898                                                                         /*}}}*/