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