apt-pkg/algorithms.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: algorithms.cc,v 1.44 2002/11/28 18:49:16 jgg Exp $
   4 /* ######################################################################
   5
   6    Algorithms - A set of misc algorithms
   7
   8    The pkgProblemResolver class has become insanely complex and
   9    very sophisticated, it handles every test case I have thrown at it
  10    to my satisfaction. Understanding exactly why all the steps the class
  11    does are required is difficult and changing though not very risky
  12    may result in other cases not working.
  13
  14    ##################################################################### */
  15                                                                         /*}}}*/
  16 // Include Files                                                        /*{{{*/
  17 #include <apt-pkg/algorithms.h>
  18 #include <apt-pkg/error.h>
  19 #include <apt-pkg/configuration.h>
  20 #include <apt-pkg/version.h>
  21 #include <apt-pkg/sptr.h>
  22 #include <apt-pkg/acquire-item.h>
  23
  24 #include <apti18n.h>
  25 #include <sys/types.h>
  26 #include <cstdlib>
  27 #include <algorithm>
  28 #include <iostream>
  29                                                                         /*}}}*/
  30 using namespace std;
  31
  32 pkgProblemResolver *pkgProblemResolver::This = 0;
  33
  34 // Simulate::Simulate - Constructor                                     /*{{{*/
  35 // ---------------------------------------------------------------------
  36 /* The legacy translations here of input Pkg iterators is obsolete,
  37    this is not necessary since the pkgCaches are fully shared now. */
  38 pkgSimulate::pkgSimulate(pkgDepCache *Cache) : pkgPackageManager(Cache),
  39                             iPolicy(Cache),
  40                             Sim(&Cache->GetCache(),&iPolicy),
  41                             group(Sim)
  42 {
  43    Sim.Init(0);
  44    Flags = new unsigned char[Cache->Head().PackageCount];
  45    memset(Flags,0,sizeof(*Flags)*Cache->Head().PackageCount);
  46
  47    // Fake a filename so as not to activate the media swapping
  48    string Jnk = "SIMULATE";
  49    for (unsigned int I = 0; I != Cache->Head().PackageCount; I++)
  50       FileNames[I] = Jnk;
  51 }
  52                                                                         /*}}}*/
  53 // Simulate::Describe - Describe a package                              /*{{{*/
  54 // ---------------------------------------------------------------------
  55 /* Parameter Current == true displays the current package version,
  56    Parameter Candidate == true displays the candidate package version */
  57 void pkgSimulate::Describe(PkgIterator Pkg,ostream &out,bool Current,bool Candidate)
  58 {
  59    VerIterator Ver(Sim);
  60
  61    out << Pkg.FullName(true);
  62
  63    if (Current == true)
  64    {
  65       Ver = Pkg.CurrentVer();
  66       if (Ver.end() == false)
  67          out << " [" << Ver.VerStr() << ']';
  68    }
  69
  70    if (Candidate == true)
  71    {
  72       Ver = Sim[Pkg].CandidateVerIter(Sim);
  73       if (Ver.end() == true)
  74          return;
  75
  76       out << " (" << Ver.VerStr() << ' ' << Ver.RelStr() << ')';
  77    }
  78 }
  79                                                                         /*}}}*/
  80 // Simulate::Install - Simulate unpacking of a package                  /*{{{*/
  81 // ---------------------------------------------------------------------
  82 /* */
  83 bool pkgSimulate::Install(PkgIterator iPkg,string /*File*/)
  84 {
  85    // Adapt the iterator
  86    PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
  87    Flags[Pkg->ID] = 1;
  88
  89    cout << "Inst ";
  90    Describe(Pkg,cout,true,true);
  91    Sim.MarkInstall(Pkg,false);
  92
  93    if (strcmp(Pkg.Arch(),"all") == 0)
  94    {
  95       pkgCache::GrpIterator G = Pkg.Group();
  96       pkgCache::GrpIterator iG = iPkg.Group();
  97       for (pkgCache::PkgIterator P = G.FindPkg("any"); P.end() != true; P = G.NextPkg(P))
  98       {
  99          if (strcmp(P.Arch(), "all") == 0)
 100             continue;
 101          if (iG.FindPkg(P.Arch())->CurrentVer == 0)
 102             continue;
 103          Flags[P->ID] = 1;
 104          Sim.MarkInstall(P, false);
 105       }
 106    }
 107
 108    // Look for broken conflicts+predepends.
 109    for (PkgIterator I = Sim.PkgBegin(); I.end() == false; I++)
 110    {
 111       if (Sim[I].InstallVer == 0)
 112          continue;
 113
 114       for (DepIterator D = Sim[I].InstVerIter(Sim).DependsList(); D.end() == false;)
 115       {
 116          DepIterator Start;
 117          DepIterator End;
 118          D.GlobOr(Start,End);
 119          if (Start->Type == pkgCache::Dep::Conflicts ||
 120              Start->Type == pkgCache::Dep::DpkgBreaks ||
 121              Start->Type == pkgCache::Dep::Obsoletes ||
 122              End->Type == pkgCache::Dep::PreDepends)
 123          {
 124             if ((Sim[End] & pkgDepCache::DepGInstall) == 0)
 125             {
 126                cout << " [" << I.FullName(false) << " on " << Start.TargetPkg().FullName(false) << ']';
 127                if (Start->Type == pkgCache::Dep::Conflicts)
 128                   _error->Error("Fatal, conflicts violated %s",I.FullName(false).c_str());
 129             }
 130          }
 131       }
 132    }
 133
 134    if (Sim.BrokenCount() != 0)
 135       ShortBreaks();
 136    else
 137       cout << endl;
 138    return true;
 139 }
 140                                                                         /*}}}*/
 141 // Simulate::Configure - Simulate configuration of a Package            /*{{{*/
 142 // ---------------------------------------------------------------------
 143 /* This is not an acurate simulation of relatity, we should really not
 144    install the package.. For some investigations it may be necessary
 145    however. */
 146 bool pkgSimulate::Configure(PkgIterator iPkg)
 147 {
 148    // Adapt the iterator
 149    PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
 150
 151    Flags[Pkg->ID] = 2;
 152
 153    if (strcmp(Pkg.Arch(),"all") == 0)
 154    {
 155       pkgCache::GrpIterator G = Pkg.Group();
 156       for (pkgCache::PkgIterator P = G.FindPkg("any"); P.end() != true; P = G.NextPkg(P))
 157       {
 158          if (strcmp(P.Arch(), "all") == 0)
 159             continue;
 160          if (Flags[P->ID] == 1)
 161             Flags[P->ID] = 2;
 162       }
 163    }
 164
 165 //   Sim.MarkInstall(Pkg,false);
 166    if (Sim[Pkg].InstBroken() == true)
 167    {
 168       cout << "Conf " << Pkg.FullName(false) << " broken" << endl;
 169
 170       Sim.Update();
 171
 172       // Print out each package and the failed dependencies
 173       for (pkgCache::DepIterator D = Sim[Pkg].InstVerIter(Sim).DependsList(); D.end() == false; D++)
 174       {
 175          if (Sim.IsImportantDep(D) == false ||
 176              (Sim[D] & pkgDepCache::DepInstall) != 0)
 177             continue;
 178
 179          if (D->Type == pkgCache::Dep::Obsoletes)
 180             cout << " Obsoletes:" << D.TargetPkg().FullName(false);
 181          else if (D->Type == pkgCache::Dep::Conflicts)
 182             cout << " Conflicts:" << D.TargetPkg().FullName(false);
 183          else if (D->Type == pkgCache::Dep::DpkgBreaks)
 184             cout << " Breaks:" << D.TargetPkg().FullName(false);
 185          else
 186             cout << " Depends:" << D.TargetPkg().FullName(false);
 187       }
 188       cout << endl;
 189
 190       _error->Error("Conf Broken %s",Pkg.FullName(false).c_str());
 191    }
 192    else
 193    {
 194       cout << "Conf ";
 195       Describe(Pkg,cout,false,true);
 196    }
 197
 198    if (Sim.BrokenCount() != 0)
 199       ShortBreaks();
 200    else
 201       cout << endl;
 202
 203    return true;
 204 }
 205                                                                         /*}}}*/
 206 // Simulate::Remove - Simulate the removal of a package                 /*{{{*/
 207 // ---------------------------------------------------------------------
 208 /* */
 209 bool pkgSimulate::Remove(PkgIterator iPkg,bool Purge)
 210 {
 211    // Adapt the iterator
 212    PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch());
 213
 214    Flags[Pkg->ID] = 3;
 215    Sim.MarkDelete(Pkg);
 216
 217    if (strcmp(Pkg.Arch(),"all") == 0)
 218    {
 219       pkgCache::GrpIterator G = Pkg.Group();
 220       pkgCache::GrpIterator iG = iPkg.Group();
 221       for (pkgCache::PkgIterator P = G.FindPkg("any"); P.end() != true; P = G.NextPkg(P))
 222       {
 223          if (strcmp(P.Arch(), "all") == 0)
 224             continue;
 225          if (iG.FindPkg(P.Arch())->CurrentVer == 0)
 226             continue;
 227          Flags[P->ID] = 3;
 228          Sim.MarkDelete(P);
 229       }
 230    }
 231
 232    if (Purge == true)
 233       cout << "Purg ";
 234    else
 235       cout << "Remv ";
 236    Describe(Pkg,cout,true,false);
 237
 238    if (Sim.BrokenCount() != 0)
 239       ShortBreaks();
 240    else
 241       cout << endl;
 242
 243    return true;
 244 }
 245                                                                         /*}}}*/
 246 // Simulate::ShortBreaks - Print out a short line describing all breaks /*{{{*/
 247 // ---------------------------------------------------------------------
 248 /* */
 249 void pkgSimulate::ShortBreaks()
 250 {
 251    cout << " [";
 252    for (PkgIterator I = Sim.PkgBegin(); I.end() == false; I++)
 253    {
 254       if (Sim[I].InstBroken() == true)
 255       {
 256          if (Flags[I->ID] == 0)
 257             cout << I.FullName(false) << ' ';
 258 /*       else
 259             cout << I.Name() << "! ";*/
 260       }
 261    }
 262    cout << ']' << endl;
 263 }
 264                                                                         /*}}}*/
 265 // ApplyStatus - Adjust for non-ok packages                             /*{{{*/
 266 // ---------------------------------------------------------------------
 267 /* We attempt to change the state of the all packages that have failed
 268    installation toward their real state. The ordering code will perform
 269    the necessary calculations to deal with the problems. */
 270 bool pkgApplyStatus(pkgDepCache &Cache)
 271 {
 272    pkgDepCache::ActionGroup group(Cache);
 273
 274    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 275    {
 276       if (I->VersionList == 0)
 277          continue;
 278
 279       // Only choice for a ReInstReq package is to reinstall
 280       if (I->InstState == pkgCache::State::ReInstReq ||
 281           I->InstState == pkgCache::State::HoldReInstReq)
 282       {
 283          if (I->CurrentVer != 0 && I.CurrentVer().Downloadable() == true)
 284             Cache.MarkKeep(I, false, false);
 285          else
 286          {
 287             // Is this right? Will dpkg choke on an upgrade?
 288             if (Cache[I].CandidateVer != 0 &&
 289                  Cache[I].CandidateVerIter(Cache).Downloadable() == true)
 290                Cache.MarkInstall(I, false, 0, false);
 291             else
 292                return _error->Error(_("The package %s needs to be reinstalled, "
 293                                     "but I can't find an archive for it."),I.FullName(true).c_str());
 294          }
 295
 296          continue;
 297       }
 298
 299       switch (I->CurrentState)
 300       {
 301          /* This means installation failed somehow - it does not need to be
 302             re-unpacked (probably) */
 303          case pkgCache::State::UnPacked:
 304          case pkgCache::State::HalfConfigured:
 305          case pkgCache::State::TriggersAwaited:
 306          case pkgCache::State::TriggersPending:
 307          if ((I->CurrentVer != 0 && I.CurrentVer().Downloadable() == true) ||
 308              I.State() != pkgCache::PkgIterator::NeedsUnpack)
 309             Cache.MarkKeep(I, false, false);
 310          else
 311          {
 312             if (Cache[I].CandidateVer != 0 &&
 313                  Cache[I].CandidateVerIter(Cache).Downloadable() == true)
 314                Cache.MarkInstall(I, true, 0, false);
 315             else
 316                Cache.MarkDelete(I);
 317          }
 318          break;
 319
 320          // This means removal failed
 321          case pkgCache::State::HalfInstalled:
 322          Cache.MarkDelete(I);
 323          break;
 324
 325          default:
 326          if (I->InstState != pkgCache::State::Ok)
 327             return _error->Error("The package %s is not ok and I "
 328                                  "don't know how to fix it!",I.FullName(false).c_str());
 329       }
 330    }
 331    return true;
 332 }
 333                                                                         /*}}}*/
 334 // FixBroken - Fix broken packages                                      /*{{{*/
 335 // ---------------------------------------------------------------------
 336 /* This autoinstalls every broken package and then runs the problem resolver
 337    on the result. */
 338 bool pkgFixBroken(pkgDepCache &Cache)
 339 {
 340    pkgDepCache::ActionGroup group(Cache);
 341
 342    // Auto upgrade all broken packages
 343    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 344       if (Cache[I].NowBroken() == true)
 345          Cache.MarkInstall(I, true, 0, false);
 346
 347    /* Fix packages that are in a NeedArchive state but don't have a
 348       downloadable install version */
 349    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 350    {
 351       if (I.State() != pkgCache::PkgIterator::NeedsUnpack ||
 352           Cache[I].Delete() == true)
 353          continue;
 354
 355       if (Cache[I].InstVerIter(Cache).Downloadable() == false)
 356          continue;
 357
 358       Cache.MarkInstall(I, true, 0, false);
 359    }
 360
 361    pkgProblemResolver Fix(&Cache);
 362    return Fix.Resolve(true);
 363 }
 364                                                                         /*}}}*/
 365 // DistUpgrade - Distribution upgrade                                   /*{{{*/
 366 // ---------------------------------------------------------------------
 367 /* This autoinstalls every package and then force installs every
 368    pre-existing package. This creates the initial set of conditions which
 369    most likely contain problems because too many things were installed.
 370
 371    The problem resolver is used to resolve the problems.
 372  */
 373 bool pkgDistUpgrade(pkgDepCache &Cache)
 374 {
 375    pkgDepCache::ActionGroup group(Cache);
 376
 377    /* Auto upgrade all installed packages, this provides the basis
 378       for the installation */
 379    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 380       if (I->CurrentVer != 0)
 381          Cache.MarkInstall(I, true, 0, false);
 382
 383    /* Now, auto upgrade all essential packages - this ensures that
 384       the essential packages are present and working */
 385    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 386       if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
 387          Cache.MarkInstall(I, true, 0, false);
 388
 389    /* We do it again over all previously installed packages to force
 390       conflict resolution on them all. */
 391    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 392       if (I->CurrentVer != 0)
 393          Cache.MarkInstall(I, false, 0, false);
 394
 395    pkgProblemResolver Fix(&Cache);
 396
 397    // Hold back held packages.
 398    if (_config->FindB("APT::Ignore-Hold",false) == false)
 399    {
 400       for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 401       {
 402          if (I->SelectedState == pkgCache::State::Hold)
 403          {
 404             Fix.Protect(I);
 405             Cache.MarkKeep(I, false, false);
 406          }
 407       }
 408    }
 409
 410    return Fix.Resolve();
 411 }
 412                                                                         /*}}}*/
 413 // AllUpgrade - Upgrade as many packages as possible                    /*{{{*/
 414 // ---------------------------------------------------------------------
 415 /* Right now the system must be consistent before this can be called.
 416    It also will not change packages marked for install, it only tries
 417    to install packages not marked for install */
 418 bool pkgAllUpgrade(pkgDepCache &Cache)
 419 {
 420    pkgDepCache::ActionGroup group(Cache);
 421
 422    pkgProblemResolver Fix(&Cache);
 423
 424    if (Cache.BrokenCount() != 0)
 425       return false;
 426
 427    // Upgrade all installed packages
 428    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 429    {
 430       if (Cache[I].Install() == true)
 431          Fix.Protect(I);
 432
 433       if (_config->FindB("APT::Ignore-Hold",false) == false)
 434          if (I->SelectedState == pkgCache::State::Hold)
 435             continue;
 436
 437       if (I->CurrentVer != 0 && Cache[I].InstallVer != 0)
 438          Cache.MarkInstall(I, false, 0, false);
 439    }
 440
 441    return Fix.ResolveByKeep();
 442 }
 443                                                                         /*}}}*/
 444 // MinimizeUpgrade - Minimizes the set of packages to be upgraded       /*{{{*/
 445 // ---------------------------------------------------------------------
 446 /* This simply goes over the entire set of packages and tries to keep
 447    each package marked for upgrade. If a conflict is generated then
 448    the package is restored. */
 449 bool pkgMinimizeUpgrade(pkgDepCache &Cache)
 450 {
 451    pkgDepCache::ActionGroup group(Cache);
 452
 453    if (Cache.BrokenCount() != 0)
 454       return false;
 455
 456    // We loop for 10 tries to get the minimal set size.
 457    bool Change = false;
 458    unsigned int Count = 0;
 459    do
 460    {
 461       Change = false;
 462       for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 463       {
 464          // Not interesting
 465          if (Cache[I].Upgrade() == false || Cache[I].NewInstall() == true)
 466             continue;
 467
 468          // Keep it and see if that is OK
 469          Cache.MarkKeep(I, false, false);
 470          if (Cache.BrokenCount() != 0)
 471             Cache.MarkInstall(I, false, 0, false);
 472          else
 473          {
 474             // If keep didnt actually do anything then there was no change..
 475             if (Cache[I].Upgrade() == false)
 476                Change = true;
 477          }
 478       }
 479       Count++;
 480    }
 481    while (Change == true && Count < 10);
 482
 483    if (Cache.BrokenCount() != 0)
 484       return _error->Error("Internal Error in pkgMinimizeUpgrade");
 485
 486    return true;
 487 }
 488                                                                         /*}}}*/
 489 // ProblemResolver::pkgProblemResolver - Constructor                    /*{{{*/
 490 // ---------------------------------------------------------------------
 491 /* */
 492 pkgProblemResolver::pkgProblemResolver(pkgDepCache *pCache) : Cache(*pCache)
 493 {
 494    // Allocate memory
 495    unsigned long Size = Cache.Head().PackageCount;
 496    Scores = new signed short[Size];
 497    Flags = new unsigned char[Size];
 498    memset(Flags,0,sizeof(*Flags)*Size);
 499
 500    // Set debug to true to see its decision logic
 501    Debug = _config->FindB("Debug::pkgProblemResolver",false);
 502 }
 503                                                                         /*}}}*/
 504 // ProblemResolver::~pkgProblemResolver - Destructor                    /*{{{*/
 505 // ---------------------------------------------------------------------
 506 /* */
 507 pkgProblemResolver::~pkgProblemResolver()
 508 {
 509    delete [] Scores;
 510    delete [] Flags;
 511 }
 512                                                                         /*}}}*/
 513 // ProblemResolver::ScoreSort - Sort the list by score                  /*{{{*/
 514 // ---------------------------------------------------------------------
 515 /* */
 516 int pkgProblemResolver::ScoreSort(const void *a,const void *b)
 517 {
 518    Package const **A = (Package const **)a;
 519    Package const **B = (Package const **)b;
 520    if (This->Scores[(*A)->ID] > This->Scores[(*B)->ID])
 521       return -1;
 522    if (This->Scores[(*A)->ID] < This->Scores[(*B)->ID])
 523       return 1;
 524    return 0;
 525 }
 526                                                                         /*}}}*/
 527 // ProblemResolver::MakeScores - Make the score table                   /*{{{*/
 528 // ---------------------------------------------------------------------
 529 /* */
 530 void pkgProblemResolver::MakeScores()
 531 {
 532    unsigned long Size = Cache.Head().PackageCount;
 533    memset(Scores,0,sizeof(*Scores)*Size);
 534
 535    // Important Required Standard Optional Extra
 536    signed short PrioMap[] = {
 537       0,
 538       (signed short) _config->FindI("pkgProblemResolver::Scores::Important",3),
 539       (signed short) _config->FindI("pkgProblemResolver::Scores::Required",2),
 540       (signed short) _config->FindI("pkgProblemResolver::Scores::Standard",1),
 541       (signed short) _config->FindI("pkgProblemResolver::Scores::Optional",-1),
 542       (signed short) _config->FindI("pkgProblemResolver::Scores::Extra",-2)
 543    };
 544    signed short PrioEssentials = _config->FindI("pkgProblemResolver::Scores::Essentials",100);
 545    signed short PrioInstalledAndNotObsolete = _config->FindI("pkgProblemResolver::Scores::NotObsolete",1);
 546    signed short PrioDepends = _config->FindI("pkgProblemResolver::Scores::Depends",1);
 547    signed short PrioRecommends = _config->FindI("pkgProblemResolver::Scores::Recommends",1);
 548    signed short AddProtected = _config->FindI("pkgProblemResolver::Scores::AddProtected",10000);
 549    signed short AddEssential = _config->FindI("pkgProblemResolver::Scores::AddEssential",5000);
 550
 551    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
 552       clog << "Settings used to calculate pkgProblemResolver::Scores::" << endl
 553          << "  Important => " << PrioMap[1] << endl
 554          << "  Required => " << PrioMap[2] << endl
 555          << "  Standard => " << PrioMap[3] << endl
 556          << "  Optional => " << PrioMap[4] << endl
 557          << "  Extra => " << PrioMap[5] << endl
 558          << "  Essentials => " << PrioEssentials << endl
 559          << "  InstalledAndNotObsolete => " << PrioInstalledAndNotObsolete << endl
 560          << "  Depends => " << PrioDepends << endl
 561          << "  Recommends => " << PrioRecommends << endl
 562          << "  AddProtected => " << AddProtected << endl
 563          << "  AddEssential => " << AddEssential << endl;
 564
 565    // Generate the base scores for a package based on its properties
 566    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 567    {
 568       if (Cache[I].InstallVer == 0)
 569          continue;
 570
 571       signed short &Score = Scores[I->ID];
 572
 573       /* This is arbitrary, it should be high enough to elevate an
 574          essantial package above most other packages but low enough
 575          to allow an obsolete essential packages to be removed by
 576          a conflicts on a powerfull normal package (ie libc6) */
 577       if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
 578          Score += PrioEssentials;
 579
 580       // We transform the priority
 581       if (Cache[I].InstVerIter(Cache)->Priority <= 5)
 582          Score += PrioMap[Cache[I].InstVerIter(Cache)->Priority];
 583
 584       /* This helps to fix oddball problems with conflicting packages
 585          on the same level. We enhance the score of installed packages
 586          if those are not obsolete
 587       */
 588       if (I->CurrentVer != 0 && Cache[I].CandidateVer != 0 && Cache[I].CandidateVerIter(Cache).Downloadable())
 589          Score += PrioInstalledAndNotObsolete;
 590    }
 591
 592    // Now that we have the base scores we go and propogate dependencies
 593    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 594    {
 595       if (Cache[I].InstallVer == 0)
 596          continue;
 597
 598       for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false; D++)
 599       {
 600          if (D->Type == pkgCache::Dep::Depends ||
 601              D->Type == pkgCache::Dep::PreDepends)
 602             Scores[D.TargetPkg()->ID] += PrioDepends;
 603          else if (D->Type == pkgCache::Dep::Recommends)
 604             Scores[D.TargetPkg()->ID] += PrioRecommends;
 605       }
 606    }
 607
 608    // Copy the scores to advoid additive looping
 609    SPtrArray<signed short> OldScores = new signed short[Size];
 610    memcpy(OldScores,Scores,sizeof(*Scores)*Size);
 611
 612    /* Now we cause 1 level of dependency inheritance, that is we add the
 613       score of the packages that depend on the target Package. This
 614       fortifies high scoring packages */
 615    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 616    {
 617       if (Cache[I].InstallVer == 0)
 618          continue;
 619
 620       for (pkgCache::DepIterator D = I.RevDependsList(); D.end() == false; D++)
 621       {
 622          // Only do it for the install version
 623          if ((pkgCache::Version *)D.ParentVer() != Cache[D.ParentPkg()].InstallVer ||
 624              (D->Type != pkgCache::Dep::Depends &&
 625               D->Type != pkgCache::Dep::PreDepends &&
 626               D->Type != pkgCache::Dep::Recommends))
 627             continue;
 628
 629          Scores[I->ID] += abs(OldScores[D.ParentPkg()->ID]);
 630       }
 631    }
 632
 633    /* Now we propogate along provides. This makes the packages that
 634       provide important packages extremely important */
 635    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 636    {
 637       for (pkgCache::PrvIterator P = I.ProvidesList(); P.end() == false; P++)
 638       {
 639          // Only do it once per package
 640          if ((pkgCache::Version *)P.OwnerVer() != Cache[P.OwnerPkg()].InstallVer)
 641             continue;
 642          Scores[P.OwnerPkg()->ID] += abs(Scores[I->ID] - OldScores[I->ID]);
 643       }
 644    }
 645
 646    /* Protected things are pushed really high up. This number should put them
 647       ahead of everything */
 648    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 649    {
 650       if ((Flags[I->ID] & Protected) != 0)
 651          Scores[I->ID] += AddProtected;
 652       if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
 653          Scores[I->ID] += AddEssential;
 654    }
 655 }
 656                                                                         /*}}}*/
 657 // ProblemResolver::DoUpgrade - Attempt to upgrade this package         /*{{{*/
 658 // ---------------------------------------------------------------------
 659 /* This goes through and tries to reinstall packages to make this package
 660    installable */
 661 bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg)
 662 {
 663    pkgDepCache::ActionGroup group(Cache);
 664
 665    if ((Flags[Pkg->ID] & Upgradable) == 0 || Cache[Pkg].Upgradable() == false)
 666       return false;
 667    if ((Flags[Pkg->ID] & Protected) == Protected)
 668       return false;
 669
 670    Flags[Pkg->ID] &= ~Upgradable;
 671
 672    bool WasKept = Cache[Pkg].Keep();
 673    Cache.MarkInstall(Pkg, false, 0, false);
 674
 675    // This must be a virtual package or something like that.
 676    if (Cache[Pkg].InstVerIter(Cache).end() == true)
 677       return false;
 678
 679    // Isolate the problem dependency
 680    bool Fail = false;
 681    for (pkgCache::DepIterator D = Cache[Pkg].InstVerIter(Cache).DependsList(); D.end() == false;)
 682    {
 683       // Compute a single dependency element (glob or)
 684       pkgCache::DepIterator Start = D;
 685       pkgCache::DepIterator End = D;
 686       unsigned char State = 0;
 687       for (bool LastOR = true; D.end() == false && LastOR == true;)
 688       {
 689          State |= Cache[D];
 690          LastOR = (D->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
 691          D++;
 692          if (LastOR == true)
 693             End = D;
 694       }
 695
 696       // We only worry about critical deps.
 697       if (End.IsCritical() != true)
 698          continue;
 699
 700       // Iterate over all the members in the or group
 701       while (1)
 702       {
 703          // Dep is ok now
 704          if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall)
 705             break;
 706
 707          // Do not change protected packages
 708          PkgIterator P = Start.SmartTargetPkg();
 709          if ((Flags[P->ID] & Protected) == Protected)
 710          {
 711             if (Debug == true)
 712                clog << "    Reinst Failed because of protected " << P.FullName(false) << endl;
 713             Fail = true;
 714          }
 715          else
 716          {
 717             // Upgrade the package if the candidate version will fix the problem.
 718             if ((Cache[Start] & pkgDepCache::DepCVer) == pkgDepCache::DepCVer)
 719             {
 720                if (DoUpgrade(P) == false)
 721                {
 722                   if (Debug == true)
 723                      clog << "    Reinst Failed because of " << P.FullName(false) << endl;
 724                   Fail = true;
 725                }
 726                else
 727                {
 728                   Fail = false;
 729                   break;
 730                }
 731             }
 732             else
 733             {
 734                /* We let the algorithm deal with conflicts on its next iteration,
 735                 it is much smarter than us */
 736                if (Start->Type == pkgCache::Dep::Conflicts ||
 737                    Start->Type == pkgCache::Dep::DpkgBreaks ||
 738                    Start->Type == pkgCache::Dep::Obsoletes)
 739                    break;
 740
 741                if (Debug == true)
 742                   clog << "    Reinst Failed early because of " << Start.TargetPkg().FullName(false) << endl;
 743                Fail = true;
 744             }
 745          }
 746
 747          if (Start == End)
 748             break;
 749          Start++;
 750       }
 751       if (Fail == true)
 752          break;
 753    }
 754
 755    // Undo our operations - it might be smart to undo everything this did..
 756    if (Fail == true)
 757    {
 758       if (WasKept == true)
 759          Cache.MarkKeep(Pkg, false, false);
 760       else
 761          Cache.MarkDelete(Pkg);
 762       return false;
 763    }
 764
 765    if (Debug == true)
 766       clog << "  Re-Instated " << Pkg.FullName(false) << endl;
 767    return true;
 768 }
 769                                                                         /*}}}*/
 770 // ProblemResolver::Resolve - Run the resolution pass                   /*{{{*/
 771 // ---------------------------------------------------------------------
 772 /* This routines works by calculating a score for each package. The score
 773    is derived by considering the package's priority and all reverse
 774    dependents giving an integer that reflects the amount of breakage that
 775    adjusting the package will inflict.
 776
 777    It goes from highest score to lowest and corrects all of the breaks by
 778    keeping or removing the dependant packages. If that fails then it removes
 779    the package itself and goes on. The routine should be able to intelligently
 780    go from any broken state to a fixed state.
 781
 782    The BrokenFix flag enables a mode where the algorithm tries to
 783    upgrade packages to advoid problems. */
 784 bool pkgProblemResolver::Resolve(bool BrokenFix)
 785 {
 786    pkgDepCache::ActionGroup group(Cache);
 787
 788    unsigned long Size = Cache.Head().PackageCount;
 789
 790    // Record which packages are marked for install
 791    bool Again = false;
 792    do
 793    {
 794       Again = false;
 795       for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 796       {
 797          if (Cache[I].Install() == true)
 798             Flags[I->ID] |= PreInstalled;
 799          else
 800          {
 801             if (Cache[I].InstBroken() == true && BrokenFix == true)
 802             {
 803                Cache.MarkInstall(I, false, 0, false);
 804                if (Cache[I].Install() == true)
 805                   Again = true;
 806             }
 807
 808             Flags[I->ID] &= ~PreInstalled;
 809          }
 810          Flags[I->ID] |= Upgradable;
 811       }
 812    }
 813    while (Again == true);
 814
 815    if (Debug == true)
 816       clog << "Starting" << endl;
 817
 818    MakeScores();
 819
 820    /* We have to order the packages so that the broken fixing pass
 821       operates from highest score to lowest. This prevents problems when
 822       high score packages cause the removal of lower score packages that
 823       would cause the removal of even lower score packages. */
 824    SPtrArray<pkgCache::Package *> PList = new pkgCache::Package *[Size];
 825    pkgCache::Package **PEnd = PList;
 826    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 827       *PEnd++ = I;
 828    This = this;
 829    qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort);
 830
 831    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
 832    {
 833       clog << "Show Scores" << endl;
 834       for (pkgCache::Package **K = PList; K != PEnd; K++)
 835          if (Scores[(*K)->ID] != 0)
 836          {
 837            pkgCache::PkgIterator Pkg(Cache,*K);
 838            clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl;
 839          }
 840    }
 841
 842    if (Debug == true)
 843       clog << "Starting 2" << endl;
 844
 845    /* Now consider all broken packages. For each broken package we either
 846       remove the package or fix it's problem. We do this once, it should
 847       not be possible for a loop to form (that is a < b < c and fixing b by
 848       changing a breaks c) */
 849    bool Change = true;
 850    bool const TryFixByInstall = _config->FindB("pkgProblemResolver::FixByInstall", true);
 851    for (int Counter = 0; Counter != 10 && Change == true; Counter++)
 852    {
 853       Change = false;
 854       for (pkgCache::Package **K = PList; K != PEnd; K++)
 855       {
 856          pkgCache::PkgIterator I(Cache,*K);
 857
 858          /* We attempt to install this and see if any breaks result,
 859             this takes care of some strange cases */
 860          if (Cache[I].CandidateVer != Cache[I].InstallVer &&
 861              I->CurrentVer != 0 && Cache[I].InstallVer != 0 &&
 862              (Flags[I->ID] & PreInstalled) != 0 &&
 863              (Flags[I->ID] & Protected) == 0 &&
 864              (Flags[I->ID] & ReInstateTried) == 0)
 865          {
 866             if (Debug == true)
 867                clog << " Try to Re-Instate (" << Counter << ") " << I.FullName(false) << endl;
 868             unsigned long OldBreaks = Cache.BrokenCount();
 869             pkgCache::Version *OldVer = Cache[I].InstallVer;
 870             Flags[I->ID] &= ReInstateTried;
 871
 872             Cache.MarkInstall(I, false, 0, false);
 873             if (Cache[I].InstBroken() == true ||
 874                 OldBreaks < Cache.BrokenCount())
 875             {
 876                if (OldVer == 0)
 877                   Cache.MarkDelete(I);
 878                else
 879                   Cache.MarkKeep(I, false, false);
 880             }
 881             else
 882                if (Debug == true)
 883                   clog << "Re-Instated " << I.FullName(false) << " (" << OldBreaks << " vs " << Cache.BrokenCount() << ')' << endl;
 884          }
 885
 886          if (Cache[I].InstallVer == 0 || Cache[I].InstBroken() == false)
 887             continue;
 888
 889          if (Debug == true)
 890             clog << "Investigating (" << Counter << ") " << I << endl;
 891
 892          // Isolate the problem dependency
 893          PackageKill KillList[100];
 894          PackageKill *LEnd = KillList;
 895          bool InOr = false;
 896          pkgCache::DepIterator Start;
 897          pkgCache::DepIterator End;
 898          PackageKill *OldEnd = LEnd;
 899
 900          enum {OrRemove,OrKeep} OrOp = OrRemove;
 901          for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList();
 902               D.end() == false || InOr == true;)
 903          {
 904             // Compute a single dependency element (glob or)
 905             if (Start == End)
 906             {
 907                // Decide what to do
 908                if (InOr == true && OldEnd == LEnd)
 909                {
 910                   if (OrOp == OrRemove)
 911                   {
 912                      if ((Flags[I->ID] & Protected) != Protected)
 913                      {
 914                         if (Debug == true)
 915                            clog << "  Or group remove for " << I.FullName(false) << endl;
 916                         Cache.MarkDelete(I);
 917                         Change = true;
 918                      }
 919                   }
 920                   else if (OrOp == OrKeep)
 921                   {
 922                      if (Debug == true)
 923                         clog << "  Or group keep for " << I.FullName(false) << endl;
 924                      Cache.MarkKeep(I, false, false);
 925                      Change = true;
 926                   }
 927                }
 928
 929                /* We do an extra loop (as above) to finalize the or group
 930                   processing */
 931                InOr = false;
 932                OrOp = OrRemove;
 933                D.GlobOr(Start,End);
 934                if (Start.end() == true)
 935                   break;
 936
 937                // We only worry about critical deps.
 938                if (End.IsCritical() != true)
 939                   continue;
 940
 941                InOr = Start != End;
 942                OldEnd = LEnd;
 943             }
 944             else
 945             {
 946                Start++;
 947                // We only worry about critical deps.
 948                if (Start.IsCritical() != true)
 949                   continue;
 950             }
 951
 952             // Dep is ok
 953             if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall)
 954             {
 955                InOr = false;
 956                continue;
 957             }
 958
 959             if (Debug == true)
 960                clog << "Broken " << Start << endl;
 961
 962             /* Look across the version list. If there are no possible
 963                targets then we keep the package and bail. This is necessary
 964                if a package has a dep on another package that cant be found */
 965             SPtrArray<pkgCache::Version *> VList = Start.AllTargets();
 966             if (*VList == 0 && (Flags[I->ID] & Protected) != Protected &&
 967                 Start->Type != pkgCache::Dep::Conflicts &&
 968                 Start->Type != pkgCache::Dep::DpkgBreaks &&
 969                 Start->Type != pkgCache::Dep::Obsoletes &&
 970                 Cache[I].NowBroken() == false)
 971             {
 972                if (InOr == true)
 973                {
 974                   /* No keep choice because the keep being OK could be the
 975                      result of another element in the OR group! */
 976                   continue;
 977                }
 978
 979                Change = true;
 980                Cache.MarkKeep(I, false, false);
 981                break;
 982             }
 983
 984             bool Done = false;
 985             for (pkgCache::Version **V = VList; *V != 0; V++)
 986             {
 987                pkgCache::VerIterator Ver(Cache,*V);
 988                pkgCache::PkgIterator Pkg = Ver.ParentPkg();
 989
 990                if (Debug == true)
 991                   clog << "  Considering " << Pkg.FullName(false) << ' ' << (int)Scores[Pkg->ID] <<
 992                   " as a solution to " << I.FullName(false) << ' ' << (int)Scores[I->ID] << endl;
 993
 994                /* Try to fix the package under consideration rather than
 995                   fiddle with the VList package */
 996                if (Scores[I->ID] <= Scores[Pkg->ID] ||
 997                    ((Cache[Start] & pkgDepCache::DepNow) == 0 &&
 998                     End->Type != pkgCache::Dep::Conflicts &&
 999                     End->Type != pkgCache::Dep::DpkgBreaks &&
1000                     End->Type != pkgCache::Dep::Obsoletes))
1001                {
1002                   // Try a little harder to fix protected packages..
1003                   if ((Flags[I->ID] & Protected) == Protected)
1004                   {
1005                      if (DoUpgrade(Pkg) == true)
1006                      {
1007                         if (Scores[Pkg->ID] > Scores[I->ID])
1008                            Scores[Pkg->ID] = Scores[I->ID];
1009                         break;
1010                      }
1011
1012                      continue;
1013                   }
1014
1015                   /* See if a keep will do, unless the package is protected,
1016                      then installing it will be necessary */
1017                   bool Installed = Cache[I].Install();
1018                   Cache.MarkKeep(I, false, false);
1019                   if (Cache[I].InstBroken() == false)
1020                   {
1021                      // Unwind operation will be keep now
1022                      if (OrOp == OrRemove)
1023                         OrOp = OrKeep;
1024
1025                      // Restore
1026                      if (InOr == true && Installed == true)
1027                         Cache.MarkInstall(I, false, 0, false);
1028
1029                      if (Debug == true)
1030                         clog << "  Holding Back " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl;
1031                   }
1032                   else
1033                   {
1034                      if (BrokenFix == false || DoUpgrade(I) == false)
1035                      {
1036                         // Consider other options
1037                         if (InOr == false)
1038                         {
1039                            if (Debug == true)
1040                               clog << "  Removing " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl;
1041                            Cache.MarkDelete(I);
1042                            if (Counter > 1 && Scores[Pkg->ID] > Scores[I->ID])
1043                               Scores[I->ID] = Scores[Pkg->ID];
1044                         }
1045                         else if (TryFixByInstall == true &&
1046                                  Start.TargetPkg()->CurrentVer == 0 &&
1047                                  Cache[Start.TargetPkg()].Delete() == false &&
1048                                  Cache.GetCandidateVer(Start.TargetPkg()).end() == false)
1049                         {
1050                            /* Before removing or keeping the package with the broken dependency
1051                               try instead to install the first not previously installed package
1052                               solving this dependency. This helps every time a previous solver
1053                               is removed by the resolver because of a conflict or alike but it is
1054                               dangerous as it could trigger new breaks/conflicts… */
1055                            if (Debug == true)
1056                               clog << "  Try Installing " << Start.TargetPkg() << " before changing " << I.FullName(false) << std::endl;
1057                            unsigned long const OldBroken = Cache.BrokenCount();
1058                            Cache.MarkInstall(Start.TargetPkg(), true, 1, false);
1059                            // FIXME: we should undo the complete MarkInstall process here
1060                            if (Cache[Start.TargetPkg()].InstBroken() == true || Cache.BrokenCount() > OldBroken)
1061                               Cache.MarkDelete(Start.TargetPkg(), false, 1, false);
1062                         }
1063                      }
1064                   }
1065
1066                   Change = true;
1067                   Done = true;
1068                   break;
1069                }
1070                else
1071                {
1072                   /* This is a conflicts, and the version we are looking
1073                      at is not the currently selected version of the
1074                      package, which means it is not necessary to
1075                      remove/keep */
1076                   if (Cache[Pkg].InstallVer != Ver &&
1077                       (Start->Type == pkgCache::Dep::Conflicts ||
1078                        Start->Type == pkgCache::Dep::Obsoletes))
1079                      continue;
1080
1081                   if (Start->Type == pkgCache::Dep::DpkgBreaks)
1082                   {
1083                      // first, try upgradring the package, if that
1084                      // does not help, the breaks goes onto the
1085                      // kill list
1086                      // FIXME: use DoUpgrade(Pkg) instead?
1087                      if (Cache[End] & pkgDepCache::DepGCVer)
1088                      {
1089                         if (Debug)
1090                            clog << "  Upgrading " << Pkg.FullName(false) << " due to Breaks field in " << I.FullName(false) << endl;
1091                         Cache.MarkInstall(Pkg, false, 0, false);
1092                         continue;
1093                      }
1094                   }
1095
1096                   // Skip adding to the kill list if it is protected
1097                   if ((Flags[Pkg->ID] & Protected) != 0)
1098                      continue;
1099
1100                   if (Debug == true)
1101                      clog << "  Added " << Pkg.FullName(false) << " to the remove list" << endl;
1102
1103                   LEnd->Pkg = Pkg;
1104                   LEnd->Dep = End;
1105                   LEnd++;
1106
1107                   if (Start->Type != pkgCache::Dep::Conflicts &&
1108                       Start->Type != pkgCache::Dep::Obsoletes)
1109                      break;
1110                }
1111             }
1112
1113             // Hm, nothing can possibly satisify this dep. Nuke it.
1114             if (VList[0] == 0 &&
1115                 Start->Type != pkgCache::Dep::Conflicts &&
1116                 Start->Type != pkgCache::Dep::DpkgBreaks &&
1117                 Start->Type != pkgCache::Dep::Obsoletes &&
1118                 (Flags[I->ID] & Protected) != Protected)
1119             {
1120                bool Installed = Cache[I].Install();
1121                Cache.MarkKeep(I);
1122                if (Cache[I].InstBroken() == false)
1123                {
1124                   // Unwind operation will be keep now
1125                   if (OrOp == OrRemove)
1126                      OrOp = OrKeep;
1127
1128                   // Restore
1129                   if (InOr == true && Installed == true)
1130                      Cache.MarkInstall(I, false, 0, false);
1131
1132                   if (Debug == true)
1133                      clog << "  Holding Back " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl;
1134                }
1135                else
1136                {
1137                   if (Debug == true)
1138                      clog << "  Removing " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl;
1139                   if (InOr == false)
1140                      Cache.MarkDelete(I);
1141                }
1142
1143                Change = true;
1144                Done = true;
1145             }
1146
1147             // Try some more
1148             if (InOr == true)
1149                continue;
1150
1151             if (Done == true)
1152                break;
1153          }
1154
1155          // Apply the kill list now
1156          if (Cache[I].InstallVer != 0)
1157          {
1158             for (PackageKill *J = KillList; J != LEnd; J++)
1159             {
1160                Change = true;
1161                if ((Cache[J->Dep] & pkgDepCache::DepGNow) == 0)
1162                {
1163                   if (J->Dep->Type == pkgCache::Dep::Conflicts ||
1164                       J->Dep->Type == pkgCache::Dep::DpkgBreaks ||
1165                       J->Dep->Type == pkgCache::Dep::Obsoletes)
1166                   {
1167                      if (Debug == true)
1168                         clog << "  Fixing " << I.FullName(false) << " via remove of " << J->Pkg.FullName(false) << endl;
1169                      Cache.MarkDelete(J->Pkg);
1170                   }
1171                }
1172                else
1173                {
1174                   if (Debug == true)
1175                      clog << "  Fixing " << I.FullName(false) << " via keep of " << J->Pkg.FullName(false) << endl;
1176                   Cache.MarkKeep(J->Pkg, false, false);
1177                }
1178
1179                if (Counter > 1)
1180                {
1181                   if (Scores[I->ID] > Scores[J->Pkg->ID])
1182                      Scores[J->Pkg->ID] = Scores[I->ID];
1183                }
1184             }
1185          }
1186       }
1187    }
1188
1189    if (Debug == true)
1190       clog << "Done" << endl;
1191
1192    if (Cache.BrokenCount() != 0)
1193    {
1194       // See if this is the result of a hold
1195       pkgCache::PkgIterator I = Cache.PkgBegin();
1196       for (;I.end() != true; I++)
1197       {
1198          if (Cache[I].InstBroken() == false)
1199             continue;
1200          if ((Flags[I->ID] & Protected) != Protected)
1201             return _error->Error(_("Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages."));
1202       }
1203       return _error->Error(_("Unable to correct problems, you have held broken packages."));
1204    }
1205
1206    // set the auto-flags (mvo: I'm not sure if we _really_ need this)
1207    pkgCache::PkgIterator I = Cache.PkgBegin();
1208    for (;I.end() != true; I++) {
1209       if (Cache[I].NewInstall() && !(Flags[I->ID] & PreInstalled)) {
1210          if(_config->FindI("Debug::pkgAutoRemove",false)) {
1211             std::clog << "Resolve installed new pkg: " << I.FullName(false)
1212                       << " (now marking it as auto)" << std::endl;
1213          }
1214          Cache[I].Flags |= pkgCache::Flag::Auto;
1215       }
1216    }
1217
1218
1219    return true;
1220 }
1221                                                                         /*}}}*/
1222 // ProblemResolver::ResolveByKeep - Resolve problems using keep         /*{{{*/
1223 // ---------------------------------------------------------------------
1224 /* This is the work horse of the soft upgrade routine. It is very gental
1225    in that it does not install or remove any packages. It is assumed that the
1226    system was non-broken previously. */
1227 bool pkgProblemResolver::ResolveByKeep()
1228 {
1229    pkgDepCache::ActionGroup group(Cache);
1230
1231    unsigned long Size = Cache.Head().PackageCount;
1232
1233    MakeScores();
1234
1235    /* We have to order the packages so that the broken fixing pass
1236       operates from highest score to lowest. This prevents problems when
1237       high score packages cause the removal of lower score packages that
1238       would cause the removal of even lower score packages. */
1239    pkgCache::Package **PList = new pkgCache::Package *[Size];
1240    pkgCache::Package **PEnd = PList;
1241    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
1242       *PEnd++ = I;
1243    This = this;
1244    qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort);
1245
1246    if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true)
1247    {
1248       clog << "Show Scores" << endl;
1249       for (pkgCache::Package **K = PList; K != PEnd; K++)
1250          if (Scores[(*K)->ID] != 0)
1251          {
1252            pkgCache::PkgIterator Pkg(Cache,*K);
1253            clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl;
1254          }
1255    }
1256
1257    if (Debug == true)
1258       clog << "Entering ResolveByKeep" << endl;
1259
1260    // Consider each broken package
1261    pkgCache::Package **LastStop = 0;
1262    for (pkgCache::Package **K = PList; K != PEnd; K++)
1263    {
1264       pkgCache::PkgIterator I(Cache,*K);
1265
1266       if (Cache[I].InstallVer == 0 || Cache[I].InstBroken() == false)
1267          continue;
1268
1269       /* Keep the package. If this works then great, otherwise we have
1270          to be significantly more agressive and manipulate its dependencies */
1271       if ((Flags[I->ID] & Protected) == 0)
1272       {
1273          if (Debug == true)
1274             clog << "Keeping package " << I.FullName(false) << endl;
1275          Cache.MarkKeep(I, false, false);
1276          if (Cache[I].InstBroken() == false)
1277          {
1278             K = PList - 1;
1279             continue;
1280          }
1281       }
1282
1283       // Isolate the problem dependencies
1284       for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false;)
1285       {
1286          DepIterator Start;
1287          DepIterator End;
1288          D.GlobOr(Start,End);
1289
1290          // We only worry about critical deps.
1291          if (End.IsCritical() != true)
1292             continue;
1293
1294          // Dep is ok
1295          if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall)
1296             continue;
1297
1298          /* Hm, the group is broken.. I suppose the best thing to do is to
1299             is to try every combination of keep/not-keep for the set, but thats
1300             slow, and this never happens, just be conservative and assume the
1301             list of ors is in preference and keep till it starts to work. */
1302          while (true)
1303          {
1304             if (Debug == true)
1305                clog << "Package " << I.FullName(false) << " " << Start << endl;
1306
1307             // Look at all the possible provides on this package
1308             SPtrArray<pkgCache::Version *> VList = Start.AllTargets();
1309             for (pkgCache::Version **V = VList; *V != 0; V++)
1310             {
1311                pkgCache::VerIterator Ver(Cache,*V);
1312                pkgCache::PkgIterator Pkg = Ver.ParentPkg();
1313
1314                // It is not keepable
1315                if (Cache[Pkg].InstallVer == 0 ||
1316                    Pkg->CurrentVer == 0)
1317                   continue;
1318
1319                if ((Flags[I->ID] & Protected) == 0)
1320                {
1321                   if (Debug == true)
1322                      clog << "  Keeping Package " << Pkg.FullName(false) << " due to " << Start.DepType() << endl;
1323                   Cache.MarkKeep(Pkg, false, false);
1324                }
1325
1326                if (Cache[I].InstBroken() == false)
1327                   break;
1328             }
1329
1330             if (Cache[I].InstBroken() == false)
1331                break;
1332
1333             if (Start == End)
1334                break;
1335             Start++;
1336          }
1337
1338          if (Cache[I].InstBroken() == false)
1339             break;
1340       }
1341
1342       if (Cache[I].InstBroken() == true)
1343          continue;
1344
1345       // Restart again.
1346       if (K == LastStop)
1347          return _error->Error("Internal Error, pkgProblemResolver::ResolveByKeep is looping on package %s.",I.FullName(false).c_str());
1348       LastStop = K;
1349       K = PList - 1;
1350    }
1351
1352    return true;
1353 }
1354                                                                         /*}}}*/
1355 // ProblemResolver::InstallProtect - Install all protected packages     /*{{{*/
1356 // ---------------------------------------------------------------------
1357 /* This is used to make sure protected packages are installed */
1358 void pkgProblemResolver::InstallProtect()
1359 {
1360    pkgDepCache::ActionGroup group(Cache);
1361
1362    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
1363    {
1364       if ((Flags[I->ID] & Protected) == Protected)
1365       {
1366          if ((Flags[I->ID] & ToRemove) == ToRemove)
1367             Cache.MarkDelete(I);
1368          else
1369          {
1370             // preserve the information whether the package was auto
1371             // or manually installed
1372             bool autoInst = (Cache[I].Flags & pkgCache::Flag::Auto);
1373             Cache.MarkInstall(I, false, 0, !autoInst);
1374          }
1375       }
1376    }
1377 }
1378                                                                         /*}}}*/
1379 // PrioSortList - Sort a list of versions by priority                   /*{{{*/
1380 // ---------------------------------------------------------------------
1381 /* This is ment to be used in conjunction with AllTargets to get a list
1382    of versions ordered by preference. */
1383 static pkgCache *PrioCache;
1384 static int PrioComp(const void *A,const void *B)
1385 {
1386    pkgCache::VerIterator L(*PrioCache,*(pkgCache::Version **)A);
1387    pkgCache::VerIterator R(*PrioCache,*(pkgCache::Version **)B);
1388
1389    if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential &&
1390        (R.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential)
1391      return 1;
1392    if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential &&
1393        (R.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
1394      return -1;
1395
1396    if (L->Priority != R->Priority)
1397       return R->Priority - L->Priority;
1398    return strcmp(L.ParentPkg().Name(),R.ParentPkg().Name());
1399 }
1400 void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List)
1401 {
1402    unsigned long Count = 0;
1403    PrioCache = &Cache;
1404    for (pkgCache::Version **I = List; *I != 0; I++)
1405       Count++;
1406    qsort(List,Count,sizeof(*List),PrioComp);
1407 }
1408                                                                         /*}}}*/
1409 // CacheFile::ListUpdate - update the cache files                       /*{{{*/
1410 // ---------------------------------------------------------------------
1411 /* This is a simple wrapper to update the cache. it will fetch stuff
1412  * from the network (or any other sources defined in sources.list)
1413  */
1414 bool ListUpdate(pkgAcquireStatus &Stat,
1415                 pkgSourceList &List,
1416                 int PulseInterval)
1417 {
1418    pkgAcquire::RunResult res;
1419    pkgAcquire Fetcher;
1420    if (Fetcher.Setup(&Stat, _config->FindDir("Dir::State::Lists")) == false)
1421       return false;
1422
1423    // Populate it with the source selection
1424    if (List.GetIndexes(&Fetcher) == false)
1425          return false;
1426
1427    // Run scripts
1428    RunScripts("APT::Update::Pre-Invoke");
1429
1430    // check arguments
1431    if(PulseInterval>0)
1432       res = Fetcher.Run(PulseInterval);
1433    else
1434       res = Fetcher.Run();
1435
1436    if (res == pkgAcquire::Failed)
1437       return false;
1438
1439    bool Failed = false;
1440    bool TransientNetworkFailure = false;
1441    for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin();
1442         I != Fetcher.ItemsEnd(); I++)
1443    {
1444       if ((*I)->Status == pkgAcquire::Item::StatDone)
1445          continue;
1446
1447       (*I)->Finished();
1448
1449       ::URI uri((*I)->DescURI());
1450       uri.User.clear();
1451       uri.Password.clear();
1452       string descUri = string(uri);
1453       _error->Warning(_("Failed to fetch %s  %s\n"), descUri.c_str(),
1454               (*I)->ErrorText.c_str());
1455
1456       if ((*I)->Status == pkgAcquire::Item::StatTransientNetworkError)
1457       {
1458          TransientNetworkFailure = true;
1459          continue;
1460       }
1461
1462       Failed = true;
1463    }
1464
1465    // Clean out any old list files
1466    // Keep "APT::Get::List-Cleanup" name for compatibility, but
1467    // this is really a global option for the APT library now
1468    if (!TransientNetworkFailure && !Failed &&
1469        (_config->FindB("APT::Get::List-Cleanup",true) == true &&
1470         _config->FindB("APT::List-Cleanup",true) == true))
1471    {
1472       if (Fetcher.Clean(_config->FindDir("Dir::State::lists")) == false ||
1473           Fetcher.Clean(_config->FindDir("Dir::State::lists") + "partial/") == false)
1474          // something went wrong with the clean
1475          return false;
1476    }
1477
1478    if (TransientNetworkFailure == true)
1479       _error->Warning(_("Some index files failed to download, they have been ignored, or old ones used instead."));
1480    else if (Failed == true)
1481       return _error->Error(_("Some index files failed to download, they have been ignored, or old ones used instead."));
1482
1483
1484    // Run the success scripts if all was fine
1485    if(!TransientNetworkFailure && !Failed)
1486       RunScripts("APT::Update::Post-Invoke-Success");
1487
1488    // Run the other scripts
1489    RunScripts("APT::Update::Post-Invoke");
1490    return true;
1491 }
1492                                                                         /*}}}*/