// -*- mode: cpp; mode: fold -*- // Description /*{{{*/ // $Id: algorithms.cc,v 1.44 2002/11/28 18:49:16 jgg Exp $ /* ###################################################################### Algorithms - A set of misc algorithms The pkgProblemResolver class has become insanely complex and very sophisticated, it handles every test case I have thrown at it to my satisfaction. Understanding exactly why all the steps the class does are required is difficult and changing though not very risky may result in other cases not working. ##################################################################### */ /*}}}*/ // Include Files /*{{{*/ #include <config.h> #include <apt-pkg/algorithms.h> #include <apt-pkg/error.h> #include <apt-pkg/configuration.h> #include <apt-pkg/version.h> #include <apt-pkg/sptr.h> #include <apt-pkg/acquire-item.h> #include <apt-pkg/edsp.h> #include <apt-pkg/sourcelist.h> #include <apt-pkg/fileutl.h> #include <apt-pkg/progress.h> #include <sys/types.h> #include <cstdlib> #include <algorithm> #include <iostream> #include <stdio.h> #include <apti18n.h> /*}}}*/ using namespace std; pkgProblemResolver *pkgProblemResolver::This = 0; // Simulate::Simulate - Constructor /*{{{*/ // --------------------------------------------------------------------- /* The legacy translations here of input Pkg iterators is obsolete, this is not necessary since the pkgCaches are fully shared now. */ pkgSimulate::pkgSimulate(pkgDepCache *Cache) : pkgPackageManager(Cache), iPolicy(Cache), Sim(&Cache->GetCache(),&iPolicy), group(Sim) { Sim.Init(0); Flags = new unsigned char[Cache->Head().PackageCount]; memset(Flags,0,sizeof(*Flags)*Cache->Head().PackageCount); // Fake a filename so as not to activate the media swapping string Jnk = "SIMULATE"; for (unsigned int I = 0; I != Cache->Head().PackageCount; I++) FileNames[I] = Jnk; } /*}}}*/ // Simulate::~Simulate - Destructor /*{{{*/ pkgSimulate::~pkgSimulate() { delete[] Flags; } /*}}}*/ // Simulate::Describe - Describe a package /*{{{*/ // --------------------------------------------------------------------- /* Parameter Current == true displays the current package version, Parameter Candidate == true displays the candidate package version */ void pkgSimulate::Describe(PkgIterator Pkg,ostream &out,bool Current,bool Candidate) { VerIterator Ver(Sim); out << Pkg.FullName(true); if (Current == true) { Ver = Pkg.CurrentVer(); if (Ver.end() == false) out << " [" << Ver.VerStr() << ']'; } if (Candidate == true) { Ver = Sim[Pkg].CandidateVerIter(Sim); if (Ver.end() == true) return; out << " (" << Ver.VerStr() << ' ' << Ver.RelStr() << ')'; } } /*}}}*/ // Simulate::Install - Simulate unpacking of a package /*{{{*/ // --------------------------------------------------------------------- /* */ bool pkgSimulate::Install(PkgIterator iPkg,string /*File*/) { // Adapt the iterator PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch()); Flags[Pkg->ID] = 1; cout << "Inst "; Describe(Pkg,cout,true,true); Sim.MarkInstall(Pkg,false); // Look for broken conflicts+predepends. for (PkgIterator I = Sim.PkgBegin(); I.end() == false; ++I) { if (Sim[I].InstallVer == 0) continue; for (DepIterator D = Sim[I].InstVerIter(Sim).DependsList(); D.end() == false;) { DepIterator Start; DepIterator End; D.GlobOr(Start,End); if (Start.IsNegative() == true || End->Type == pkgCache::Dep::PreDepends) { if ((Sim[End] & pkgDepCache::DepGInstall) == 0) { cout << " [" << I.FullName(false) << " on " << Start.TargetPkg().FullName(false) << ']'; if (Start->Type == pkgCache::Dep::Conflicts) _error->Error("Fatal, conflicts violated %s",I.FullName(false).c_str()); } } } } if (Sim.BrokenCount() != 0) ShortBreaks(); else cout << endl; return true; } /*}}}*/ // Simulate::Configure - Simulate configuration of a Package /*{{{*/ // --------------------------------------------------------------------- /* This is not an acurate simulation of relatity, we should really not install the package.. For some investigations it may be necessary however. */ bool pkgSimulate::Configure(PkgIterator iPkg) { // Adapt the iterator PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch()); Flags[Pkg->ID] = 2; if (Sim[Pkg].InstBroken() == true) { cout << "Conf " << Pkg.FullName(false) << " broken" << endl; Sim.Update(); // Print out each package and the failed dependencies for (pkgCache::DepIterator D = Sim[Pkg].InstVerIter(Sim).DependsList(); D.end() == false; ++D) { if (Sim.IsImportantDep(D) == false || (Sim[D] & pkgDepCache::DepInstall) != 0) continue; if (D->Type == pkgCache::Dep::Obsoletes) cout << " Obsoletes:" << D.TargetPkg().FullName(false); else if (D->Type == pkgCache::Dep::Conflicts) cout << " Conflicts:" << D.TargetPkg().FullName(false); else if (D->Type == pkgCache::Dep::DpkgBreaks) cout << " Breaks:" << D.TargetPkg().FullName(false); else cout << " Depends:" << D.TargetPkg().FullName(false); } cout << endl; _error->Error("Conf Broken %s",Pkg.FullName(false).c_str()); } else { cout << "Conf "; Describe(Pkg,cout,false,true); } if (Sim.BrokenCount() != 0) ShortBreaks(); else cout << endl; return true; } /*}}}*/ // Simulate::Remove - Simulate the removal of a package /*{{{*/ // --------------------------------------------------------------------- /* */ bool pkgSimulate::Remove(PkgIterator iPkg,bool Purge) { // Adapt the iterator PkgIterator Pkg = Sim.FindPkg(iPkg.Name(), iPkg.Arch()); Flags[Pkg->ID] = 3; Sim.MarkDelete(Pkg); if (Purge == true) cout << "Purg "; else cout << "Remv "; Describe(Pkg,cout,true,false); if (Sim.BrokenCount() != 0) ShortBreaks(); else cout << endl; return true; } /*}}}*/ // Simulate::ShortBreaks - Print out a short line describing all breaks /*{{{*/ // --------------------------------------------------------------------- /* */ void pkgSimulate::ShortBreaks() { cout << " ["; for (PkgIterator I = Sim.PkgBegin(); I.end() == false; ++I) { if (Sim[I].InstBroken() == true) { if (Flags[I->ID] == 0) cout << I.FullName(false) << ' '; /* else cout << I.Name() << "! ";*/ } } cout << ']' << endl; } /*}}}*/ // ApplyStatus - Adjust for non-ok packages /*{{{*/ // --------------------------------------------------------------------- /* We attempt to change the state of the all packages that have failed installation toward their real state. The ordering code will perform the necessary calculations to deal with the problems. */ bool pkgApplyStatus(pkgDepCache &Cache) { pkgDepCache::ActionGroup group(Cache); for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (I->VersionList == 0) continue; // Only choice for a ReInstReq package is to reinstall if (I->InstState == pkgCache::State::ReInstReq || I->InstState == pkgCache::State::HoldReInstReq) { if (I->CurrentVer != 0 && I.CurrentVer().Downloadable() == true) Cache.MarkKeep(I, false, false); else { // Is this right? Will dpkg choke on an upgrade? if (Cache[I].CandidateVer != 0 && Cache[I].CandidateVerIter(Cache).Downloadable() == true) Cache.MarkInstall(I, false, 0, false); else return _error->Error(_("The package %s needs to be reinstalled, " "but I can't find an archive for it."),I.FullName(true).c_str()); } continue; } switch (I->CurrentState) { /* This means installation failed somehow - it does not need to be re-unpacked (probably) */ case pkgCache::State::UnPacked: case pkgCache::State::HalfConfigured: case pkgCache::State::TriggersAwaited: case pkgCache::State::TriggersPending: if ((I->CurrentVer != 0 && I.CurrentVer().Downloadable() == true) || I.State() != pkgCache::PkgIterator::NeedsUnpack) Cache.MarkKeep(I, false, false); else { if (Cache[I].CandidateVer != 0 && Cache[I].CandidateVerIter(Cache).Downloadable() == true) Cache.MarkInstall(I, true, 0, false); else Cache.MarkDelete(I); } break; // This means removal failed case pkgCache::State::HalfInstalled: Cache.MarkDelete(I); break; default: if (I->InstState != pkgCache::State::Ok) return _error->Error("The package %s is not ok and I " "don't know how to fix it!",I.FullName(false).c_str()); } } return true; } /*}}}*/ // FixBroken - Fix broken packages /*{{{*/ // --------------------------------------------------------------------- /* This autoinstalls every broken package and then runs the problem resolver on the result. */ bool pkgFixBroken(pkgDepCache &Cache) { pkgDepCache::ActionGroup group(Cache); // Auto upgrade all broken packages for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) if (Cache[I].NowBroken() == true) Cache.MarkInstall(I, true, 0, false); /* Fix packages that are in a NeedArchive state but don't have a downloadable install version */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (I.State() != pkgCache::PkgIterator::NeedsUnpack || Cache[I].Delete() == true) continue; if (Cache[I].InstVerIter(Cache).Downloadable() == false) continue; Cache.MarkInstall(I, true, 0, false); } pkgProblemResolver Fix(&Cache); return Fix.Resolve(true); } /*}}}*/ // DistUpgrade - Distribution upgrade /*{{{*/ // --------------------------------------------------------------------- /* This autoinstalls every package and then force installs every pre-existing package. This creates the initial set of conditions which most likely contain problems because too many things were installed. The problem resolver is used to resolve the problems. */ bool pkgDistUpgrade(pkgDepCache &Cache) { std::string const solver = _config->Find("APT::Solver", "internal"); if (solver != "internal") { OpTextProgress Prog(*_config); return EDSP::ResolveExternal(solver.c_str(), Cache, false, true, false, &Prog); } pkgDepCache::ActionGroup group(Cache); /* Upgrade all installed packages first without autoinst to help the resolver in versioned or-groups to upgrade the old solver instead of installing a new one (if the old solver is not the first one [anymore]) */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) if (I->CurrentVer != 0) Cache.MarkInstall(I, false, 0, false); /* Auto upgrade all installed packages, this provides the basis for the installation */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) if (I->CurrentVer != 0) Cache.MarkInstall(I, true, 0, false); /* Now, install each essential package which is not installed (and not provided by another package in the same name group) */ std::string essential = _config->Find("pkgCacheGen::Essential", "all"); if (essential == "all") { for (pkgCache::GrpIterator G = Cache.GrpBegin(); G.end() == false; ++G) { bool isEssential = false; bool instEssential = false; for (pkgCache::PkgIterator P = G.PackageList(); P.end() == false; P = G.NextPkg(P)) { if ((P->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential) continue; isEssential = true; if (Cache[P].Install() == true) { instEssential = true; break; } } if (isEssential == false || instEssential == true) continue; pkgCache::PkgIterator P = G.FindPreferredPkg(); Cache.MarkInstall(P, true, 0, false); } } else if (essential != "none") for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential) Cache.MarkInstall(I, true, 0, false); /* We do it again over all previously installed packages to force conflict resolution on them all. */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) if (I->CurrentVer != 0) Cache.MarkInstall(I, false, 0, false); pkgProblemResolver Fix(&Cache); // Hold back held packages. if (_config->FindB("APT::Ignore-Hold",false) == false) { for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (I->SelectedState == pkgCache::State::Hold) { Fix.Protect(I); Cache.MarkKeep(I, false, false); } } } return Fix.Resolve(); } /*}}}*/ // AllUpgrade - Upgrade as many packages as possible /*{{{*/ // --------------------------------------------------------------------- /* Right now the system must be consistent before this can be called. It also will not change packages marked for install, it only tries to install packages not marked for install */ bool pkgAllUpgrade(pkgDepCache &Cache) { std::string const solver = _config->Find("APT::Solver", "internal"); if (solver != "internal") { OpTextProgress Prog(*_config); return EDSP::ResolveExternal(solver.c_str(), Cache, true, false, false, &Prog); } pkgDepCache::ActionGroup group(Cache); pkgProblemResolver Fix(&Cache); if (Cache.BrokenCount() != 0) return false; // Upgrade all installed packages for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (Cache[I].Install() == true) Fix.Protect(I); if (_config->FindB("APT::Ignore-Hold",false) == false) if (I->SelectedState == pkgCache::State::Hold) continue; if (I->CurrentVer != 0 && Cache[I].InstallVer != 0) Cache.MarkInstall(I, false, 0, false); } return Fix.ResolveByKeep(); } /*}}}*/ // MinimizeUpgrade - Minimizes the set of packages to be upgraded /*{{{*/ // --------------------------------------------------------------------- /* This simply goes over the entire set of packages and tries to keep each package marked for upgrade. If a conflict is generated then the package is restored. */ bool pkgMinimizeUpgrade(pkgDepCache &Cache) { pkgDepCache::ActionGroup group(Cache); if (Cache.BrokenCount() != 0) return false; // We loop for 10 tries to get the minimal set size. bool Change = false; unsigned int Count = 0; do { Change = false; for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { // Not interesting if (Cache[I].Upgrade() == false || Cache[I].NewInstall() == true) continue; // Keep it and see if that is OK Cache.MarkKeep(I, false, false); if (Cache.BrokenCount() != 0) Cache.MarkInstall(I, false, 0, false); else { // If keep didnt actually do anything then there was no change.. if (Cache[I].Upgrade() == false) Change = true; } } ++Count; } while (Change == true && Count < 10); if (Cache.BrokenCount() != 0) return _error->Error("Internal Error in pkgMinimizeUpgrade"); return true; } /*}}}*/ // ProblemResolver::pkgProblemResolver - Constructor /*{{{*/ // --------------------------------------------------------------------- /* */ pkgProblemResolver::pkgProblemResolver(pkgDepCache *pCache) : d(NULL), Cache(*pCache) { // Allocate memory unsigned long Size = Cache.Head().PackageCount; Scores = new int[Size]; Flags = new unsigned char[Size]; memset(Flags,0,sizeof(*Flags)*Size); // Set debug to true to see its decision logic Debug = _config->FindB("Debug::pkgProblemResolver",false); } /*}}}*/ // ProblemResolver::~pkgProblemResolver - Destructor /*{{{*/ // --------------------------------------------------------------------- /* */ pkgProblemResolver::~pkgProblemResolver() { delete [] Scores; delete [] Flags; } /*}}}*/ // ProblemResolver::ScoreSort - Sort the list by score /*{{{*/ // --------------------------------------------------------------------- /* */ int pkgProblemResolver::ScoreSort(const void *a,const void *b) { Package const **A = (Package const **)a; Package const **B = (Package const **)b; if (This->Scores[(*A)->ID] > This->Scores[(*B)->ID]) return -1; if (This->Scores[(*A)->ID] < This->Scores[(*B)->ID]) return 1; return 0; } /*}}}*/ // ProblemResolver::MakeScores - Make the score table /*{{{*/ // --------------------------------------------------------------------- /* */ void pkgProblemResolver::MakeScores() { unsigned long Size = Cache.Head().PackageCount; memset(Scores,0,sizeof(*Scores)*Size); // Important Required Standard Optional Extra int PrioMap[] = { 0, _config->FindI("pkgProblemResolver::Scores::Important",3), _config->FindI("pkgProblemResolver::Scores::Required",2), _config->FindI("pkgProblemResolver::Scores::Standard",1), _config->FindI("pkgProblemResolver::Scores::Optional",-1), _config->FindI("pkgProblemResolver::Scores::Extra",-2) }; int PrioEssentials = _config->FindI("pkgProblemResolver::Scores::Essentials",100); int PrioInstalledAndNotObsolete = _config->FindI("pkgProblemResolver::Scores::NotObsolete",1); int PrioDepends = _config->FindI("pkgProblemResolver::Scores::Depends",1); int PrioRecommends = _config->FindI("pkgProblemResolver::Scores::Recommends",1); int AddProtected = _config->FindI("pkgProblemResolver::Scores::AddProtected",10000); int AddEssential = _config->FindI("pkgProblemResolver::Scores::AddEssential",5000); if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true) clog << "Settings used to calculate pkgProblemResolver::Scores::" << endl << " Important => " << PrioMap[1] << endl << " Required => " << PrioMap[2] << endl << " Standard => " << PrioMap[3] << endl << " Optional => " << PrioMap[4] << endl << " Extra => " << PrioMap[5] << endl << " Essentials => " << PrioEssentials << endl << " InstalledAndNotObsolete => " << PrioInstalledAndNotObsolete << endl << " Depends => " << PrioDepends << endl << " Recommends => " << PrioRecommends << endl << " AddProtected => " << AddProtected << endl << " AddEssential => " << AddEssential << endl; // Generate the base scores for a package based on its properties for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (Cache[I].InstallVer == 0) continue; int &Score = Scores[I->ID]; /* This is arbitrary, it should be high enough to elevate an essantial package above most other packages but low enough to allow an obsolete essential packages to be removed by a conflicts on a powerfull normal package (ie libc6) */ if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential || (I->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important) Score += PrioEssentials; // We transform the priority if (Cache[I].InstVerIter(Cache)->Priority <= 5) Score += PrioMap[Cache[I].InstVerIter(Cache)->Priority]; /* This helps to fix oddball problems with conflicting packages on the same level. We enhance the score of installed packages if those are not obsolete */ if (I->CurrentVer != 0 && Cache[I].CandidateVer != 0 && Cache[I].CandidateVerIter(Cache).Downloadable()) Score += PrioInstalledAndNotObsolete; } // Now that we have the base scores we go and propogate dependencies for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (Cache[I].InstallVer == 0) continue; for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false; ++D) { if (D->Type == pkgCache::Dep::Depends || D->Type == pkgCache::Dep::PreDepends) Scores[D.TargetPkg()->ID] += PrioDepends; else if (D->Type == pkgCache::Dep::Recommends) Scores[D.TargetPkg()->ID] += PrioRecommends; } } // Copy the scores to advoid additive looping SPtrArray<int> OldScores = new int[Size]; memcpy(OldScores,Scores,sizeof(*Scores)*Size); /* Now we cause 1 level of dependency inheritance, that is we add the score of the packages that depend on the target Package. This fortifies high scoring packages */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (Cache[I].InstallVer == 0) continue; for (pkgCache::DepIterator D = I.RevDependsList(); D.end() == false; ++D) { // Only do it for the install version if ((pkgCache::Version *)D.ParentVer() != Cache[D.ParentPkg()].InstallVer || (D->Type != pkgCache::Dep::Depends && D->Type != pkgCache::Dep::PreDepends && D->Type != pkgCache::Dep::Recommends)) continue; Scores[I->ID] += abs(OldScores[D.ParentPkg()->ID]); } } /* Now we propogate along provides. This makes the packages that provide important packages extremely important */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { for (pkgCache::PrvIterator P = I.ProvidesList(); P.end() == false; ++P) { // Only do it once per package if ((pkgCache::Version *)P.OwnerVer() != Cache[P.OwnerPkg()].InstallVer) continue; Scores[P.OwnerPkg()->ID] += abs(Scores[I->ID] - OldScores[I->ID]); } } /* Protected things are pushed really high up. This number should put them ahead of everything */ for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if ((Flags[I->ID] & Protected) != 0) Scores[I->ID] += AddProtected; if ((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential || (I->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important) Scores[I->ID] += AddEssential; } } /*}}}*/ // ProblemResolver::DoUpgrade - Attempt to upgrade this package /*{{{*/ // --------------------------------------------------------------------- /* This goes through and tries to reinstall packages to make this package installable */ bool pkgProblemResolver::DoUpgrade(pkgCache::PkgIterator Pkg) { pkgDepCache::ActionGroup group(Cache); if ((Flags[Pkg->ID] & Upgradable) == 0 || Cache[Pkg].Upgradable() == false) return false; if ((Flags[Pkg->ID] & Protected) == Protected) return false; Flags[Pkg->ID] &= ~Upgradable; bool WasKept = Cache[Pkg].Keep(); Cache.MarkInstall(Pkg, false, 0, false); // This must be a virtual package or something like that. if (Cache[Pkg].InstVerIter(Cache).end() == true) return false; // Isolate the problem dependency bool Fail = false; for (pkgCache::DepIterator D = Cache[Pkg].InstVerIter(Cache).DependsList(); D.end() == false;) { // Compute a single dependency element (glob or) pkgCache::DepIterator Start = D; pkgCache::DepIterator End = D; for (bool LastOR = true; D.end() == false && LastOR == true;) { LastOR = (D->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or; ++D; if (LastOR == true) End = D; } // We only worry about critical deps. if (End.IsCritical() != true) continue; // Iterate over all the members in the or group while (1) { // Dep is ok now if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall) break; // Do not change protected packages PkgIterator P = Start.SmartTargetPkg(); if ((Flags[P->ID] & Protected) == Protected) { if (Debug == true) clog << " Reinst Failed because of protected " << P.FullName(false) << endl; Fail = true; } else { // Upgrade the package if the candidate version will fix the problem. if ((Cache[Start] & pkgDepCache::DepCVer) == pkgDepCache::DepCVer) { if (DoUpgrade(P) == false) { if (Debug == true) clog << " Reinst Failed because of " << P.FullName(false) << endl; Fail = true; } else { Fail = false; break; } } else { /* We let the algorithm deal with conflicts on its next iteration, it is much smarter than us */ if (Start.IsNegative() == true) break; if (Debug == true) clog << " Reinst Failed early because of " << Start.TargetPkg().FullName(false) << endl; Fail = true; } } if (Start == End) break; ++Start; } if (Fail == true) break; } // Undo our operations - it might be smart to undo everything this did.. if (Fail == true) { if (WasKept == true) Cache.MarkKeep(Pkg, false, false); else Cache.MarkDelete(Pkg); return false; } if (Debug == true) clog << " Re-Instated " << Pkg.FullName(false) << endl; return true; } /*}}}*/ // ProblemResolver::Resolve - calls a resolver to fix the situation /*{{{*/ // --------------------------------------------------------------------- /* */ bool pkgProblemResolver::Resolve(bool BrokenFix) { std::string const solver = _config->Find("APT::Solver", "internal"); if (solver != "internal") { OpTextProgress Prog(*_config); return EDSP::ResolveExternal(solver.c_str(), Cache, false, false, false, &Prog); } return ResolveInternal(BrokenFix); } /*}}}*/ // ProblemResolver::ResolveInternal - Run the resolution pass /*{{{*/ // --------------------------------------------------------------------- /* This routines works by calculating a score for each package. The score is derived by considering the package's priority and all reverse dependents giving an integer that reflects the amount of breakage that adjusting the package will inflict. It goes from highest score to lowest and corrects all of the breaks by keeping or removing the dependant packages. If that fails then it removes the package itself and goes on. The routine should be able to intelligently go from any broken state to a fixed state. The BrokenFix flag enables a mode where the algorithm tries to upgrade packages to advoid problems. */ bool pkgProblemResolver::ResolveInternal(bool const BrokenFix) { pkgDepCache::ActionGroup group(Cache); // Record which packages are marked for install bool Again = false; do { Again = false; for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if (Cache[I].Install() == true) Flags[I->ID] |= PreInstalled; else { if (Cache[I].InstBroken() == true && BrokenFix == true) { Cache.MarkInstall(I, false, 0, false); if (Cache[I].Install() == true) Again = true; } Flags[I->ID] &= ~PreInstalled; } Flags[I->ID] |= Upgradable; } } while (Again == true); if (Debug == true) clog << "Starting" << endl; MakeScores(); unsigned long const Size = Cache.Head().PackageCount; /* We have to order the packages so that the broken fixing pass operates from highest score to lowest. This prevents problems when high score packages cause the removal of lower score packages that would cause the removal of even lower score packages. */ SPtrArray<pkgCache::Package *> PList = new pkgCache::Package *[Size]; pkgCache::Package **PEnd = PList; for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) *PEnd++ = I; This = this; qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort); if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true) { clog << "Show Scores" << endl; for (pkgCache::Package **K = PList; K != PEnd; K++) if (Scores[(*K)->ID] != 0) { pkgCache::PkgIterator Pkg(Cache,*K); clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl; } } if (Debug == true) clog << "Starting 2" << endl; /* Now consider all broken packages. For each broken package we either remove the package or fix it's problem. We do this once, it should not be possible for a loop to form (that is a < b < c and fixing b by changing a breaks c) */ bool Change = true; bool const TryFixByInstall = _config->FindB("pkgProblemResolver::FixByInstall", true); for (int Counter = 0; Counter != 10 && Change == true; Counter++) { Change = false; for (pkgCache::Package **K = PList; K != PEnd; K++) { pkgCache::PkgIterator I(Cache,*K); /* We attempt to install this and see if any breaks result, this takes care of some strange cases */ if (Cache[I].CandidateVer != Cache[I].InstallVer && I->CurrentVer != 0 && Cache[I].InstallVer != 0 && (Flags[I->ID] & PreInstalled) != 0 && (Flags[I->ID] & Protected) == 0 && (Flags[I->ID] & ReInstateTried) == 0) { if (Debug == true) clog << " Try to Re-Instate (" << Counter << ") " << I.FullName(false) << endl; unsigned long OldBreaks = Cache.BrokenCount(); pkgCache::Version *OldVer = Cache[I].InstallVer; Flags[I->ID] &= ReInstateTried; Cache.MarkInstall(I, false, 0, false); if (Cache[I].InstBroken() == true || OldBreaks < Cache.BrokenCount()) { if (OldVer == 0) Cache.MarkDelete(I); else Cache.MarkKeep(I, false, false); } else if (Debug == true) clog << "Re-Instated " << I.FullName(false) << " (" << OldBreaks << " vs " << Cache.BrokenCount() << ')' << endl; } if (Cache[I].InstallVer == 0 || Cache[I].InstBroken() == false) continue; if (Debug == true) clog << "Investigating (" << Counter << ") " << I << endl; // Isolate the problem dependency PackageKill KillList[100]; PackageKill *LEnd = KillList; bool InOr = false; pkgCache::DepIterator Start; pkgCache::DepIterator End; PackageKill *OldEnd = LEnd; enum {OrRemove,OrKeep} OrOp = OrRemove; for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false || InOr == true;) { // Compute a single dependency element (glob or) if (Start == End) { // Decide what to do if (InOr == true && OldEnd == LEnd) { if (OrOp == OrRemove) { if ((Flags[I->ID] & Protected) != Protected) { if (Debug == true) clog << " Or group remove for " << I.FullName(false) << endl; Cache.MarkDelete(I); Change = true; } } else if (OrOp == OrKeep) { if (Debug == true) clog << " Or group keep for " << I.FullName(false) << endl; Cache.MarkKeep(I, false, false); Change = true; } } /* We do an extra loop (as above) to finalize the or group processing */ InOr = false; OrOp = OrRemove; D.GlobOr(Start,End); if (Start.end() == true) break; // We only worry about critical deps. if (End.IsCritical() != true) continue; InOr = Start != End; OldEnd = LEnd; } else { ++Start; // We only worry about critical deps. if (Start.IsCritical() != true) continue; } // Dep is ok if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall) { InOr = false; continue; } if (Debug == true) clog << "Broken " << Start << endl; /* Look across the version list. If there are no possible targets then we keep the package and bail. This is necessary if a package has a dep on another package that cant be found */ SPtrArray<pkgCache::Version *> VList = Start.AllTargets(); if (*VList == 0 && (Flags[I->ID] & Protected) != Protected && Start.IsNegative() == false && Cache[I].NowBroken() == false) { if (InOr == true) { /* No keep choice because the keep being OK could be the result of another element in the OR group! */ continue; } Change = true; Cache.MarkKeep(I, false, false); break; } bool Done = false; for (pkgCache::Version **V = VList; *V != 0; V++) { pkgCache::VerIterator Ver(Cache,*V); pkgCache::PkgIterator Pkg = Ver.ParentPkg(); /* This is a conflicts, and the version we are looking at is not the currently selected version of the package, which means it is not necessary to remove/keep */ if (Cache[Pkg].InstallVer != Ver && Start.IsNegative() == true) { if (Debug) clog << " Conflicts//Breaks against version " << Ver.VerStr() << " for " << Pkg.Name() << " but that is not InstVer, ignoring" << endl; continue; } if (Debug == true) clog << " Considering " << Pkg.FullName(false) << ' ' << (int)Scores[Pkg->ID] << " as a solution to " << I.FullName(false) << ' ' << (int)Scores[I->ID] << endl; /* Try to fix the package under consideration rather than fiddle with the VList package */ if (Scores[I->ID] <= Scores[Pkg->ID] || ((Cache[Start] & pkgDepCache::DepNow) == 0 && End.IsNegative() == false)) { // Try a little harder to fix protected packages.. if ((Flags[I->ID] & Protected) == Protected) { if (DoUpgrade(Pkg) == true) { if (Scores[Pkg->ID] > Scores[I->ID]) Scores[Pkg->ID] = Scores[I->ID]; break; } continue; } /* See if a keep will do, unless the package is protected, then installing it will be necessary */ bool Installed = Cache[I].Install(); Cache.MarkKeep(I, false, false); if (Cache[I].InstBroken() == false) { // Unwind operation will be keep now if (OrOp == OrRemove) OrOp = OrKeep; // Restore if (InOr == true && Installed == true) Cache.MarkInstall(I, false, 0, false); if (Debug == true) clog << " Holding Back " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl; } else { if (BrokenFix == false || DoUpgrade(I) == false) { // Consider other options if (InOr == false || Cache[I].Garbage == true) { if (Debug == true) clog << " Removing " << I.FullName(false) << " rather than change " << Start.TargetPkg().FullName(false) << endl; Cache.MarkDelete(I); if (Counter > 1 && Scores[Pkg->ID] > Scores[I->ID]) Scores[I->ID] = Scores[Pkg->ID]; } else if (TryFixByInstall == true && Start.TargetPkg()->CurrentVer == 0 && Cache[Start.TargetPkg()].Delete() == false && (Flags[Start.TargetPkg()->ID] & ToRemove) != ToRemove && Cache.GetCandidateVer(Start.TargetPkg()).end() == false) { /* Before removing or keeping the package with the broken dependency try instead to install the first not previously installed package solving this dependency. This helps every time a previous solver is removed by the resolver because of a conflict or alike but it is dangerous as it could trigger new breaks/conflicts… */ if (Debug == true) clog << " Try Installing " << Start.TargetPkg() << " before changing " << I.FullName(false) << std::endl; unsigned long const OldBroken = Cache.BrokenCount(); Cache.MarkInstall(Start.TargetPkg(), true, 1, false); // FIXME: we should undo the complete MarkInstall process here if (Cache[Start.TargetPkg()].InstBroken() == true || Cache.BrokenCount() > OldBroken) Cache.MarkDelete(Start.TargetPkg(), false, 1, false); } } } Change = true; Done = true; break; } else { if (Start->Type == pkgCache::Dep::DpkgBreaks) { // first, try upgradring the package, if that // does not help, the breaks goes onto the // kill list // // FIXME: use DoUpgrade(Pkg) instead? if (Cache[End] & pkgDepCache::DepGCVer) { if (Debug) clog << " Upgrading " << Pkg.FullName(false) << " due to Breaks field in " << I.FullName(false) << endl; Cache.MarkInstall(Pkg, false, 0, false); continue; } } // Skip adding to the kill list if it is protected if ((Flags[Pkg->ID] & Protected) != 0) continue; if (Debug == true) clog << " Added " << Pkg.FullName(false) << " to the remove list" << endl; LEnd->Pkg = Pkg; LEnd->Dep = End; LEnd++; if (Start.IsNegative() == false) break; } } // Hm, nothing can possibly satisify this dep. Nuke it. if (VList[0] == 0 && Start.IsNegative() == false && (Flags[I->ID] & Protected) != Protected) { bool Installed = Cache[I].Install(); Cache.MarkKeep(I); if (Cache[I].InstBroken() == false) { // Unwind operation will be keep now if (OrOp == OrRemove) OrOp = OrKeep; // Restore if (InOr == true && Installed == true) Cache.MarkInstall(I, false, 0, false); if (Debug == true) clog << " Holding Back " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl; } else { if (Debug == true) clog << " Removing " << I.FullName(false) << " because I can't find " << Start.TargetPkg().FullName(false) << endl; if (InOr == false) Cache.MarkDelete(I); } Change = true; Done = true; } // Try some more if (InOr == true) continue; if (Done == true) break; } // Apply the kill list now if (Cache[I].InstallVer != 0) { for (PackageKill *J = KillList; J != LEnd; J++) { Change = true; if ((Cache[J->Dep] & pkgDepCache::DepGNow) == 0) { if (J->Dep.IsNegative() == true) { if (Debug == true) clog << " Fixing " << I.FullName(false) << " via remove of " << J->Pkg.FullName(false) << endl; Cache.MarkDelete(J->Pkg); } } else { if (Debug == true) clog << " Fixing " << I.FullName(false) << " via keep of " << J->Pkg.FullName(false) << endl; Cache.MarkKeep(J->Pkg, false, false); } if (Counter > 1) { if (Scores[I->ID] > Scores[J->Pkg->ID]) Scores[J->Pkg->ID] = Scores[I->ID]; } } } } } if (Debug == true) clog << "Done" << endl; if (Cache.BrokenCount() != 0) { // See if this is the result of a hold pkgCache::PkgIterator I = Cache.PkgBegin(); for (;I.end() != true; ++I) { if (Cache[I].InstBroken() == false) continue; if ((Flags[I->ID] & Protected) != Protected) return _error->Error(_("Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.")); } return _error->Error(_("Unable to correct problems, you have held broken packages.")); } // set the auto-flags (mvo: I'm not sure if we _really_ need this) pkgCache::PkgIterator I = Cache.PkgBegin(); for (;I.end() != true; ++I) { if (Cache[I].NewInstall() && !(Flags[I->ID] & PreInstalled)) { if(_config->FindI("Debug::pkgAutoRemove",false)) { std::clog << "Resolve installed new pkg: " << I.FullName(false) << " (now marking it as auto)" << std::endl; } Cache[I].Flags |= pkgCache::Flag::Auto; } } return true; } /*}}}*/ // ProblemResolver::BreaksInstOrPolicy - Check if the given pkg is broken/*{{{*/ // --------------------------------------------------------------------- /* This checks if the given package is broken either by a hard dependency (InstBroken()) or by introducing a new policy breakage e.g. new unsatisfied recommends for a package that was in "policy-good" state Note that this is not perfect as it will ignore further breakage for already broken policy (recommends) */ bool pkgProblemResolver::InstOrNewPolicyBroken(pkgCache::PkgIterator I) { // a broken install is always a problem if (Cache[I].InstBroken() == true) { if (Debug == true) std::clog << " Dependencies are not satisfied for " << I << std::endl; return true; } // a newly broken policy (recommends/suggests) is a problem if (Cache[I].NowPolicyBroken() == false && Cache[I].InstPolicyBroken() == true) { if (Debug == true) std::clog << " Policy breaks with upgrade of " << I << std::endl; return true; } return false; } /*}}}*/ // ProblemResolver::ResolveByKeep - Resolve problems using keep /*{{{*/ // --------------------------------------------------------------------- /* This is the work horse of the soft upgrade routine. It is very gental in that it does not install or remove any packages. It is assumed that the system was non-broken previously. */ bool pkgProblemResolver::ResolveByKeep() { std::string const solver = _config->Find("APT::Solver", "internal"); if (solver != "internal") { OpTextProgress Prog(*_config); return EDSP::ResolveExternal(solver.c_str(), Cache, true, false, false, &Prog); } return ResolveByKeepInternal(); } /*}}}*/ // ProblemResolver::ResolveByKeepInternal - Resolve problems using keep /*{{{*/ // --------------------------------------------------------------------- /* This is the work horse of the soft upgrade routine. It is very gental in that it does not install or remove any packages. It is assumed that the system was non-broken previously. */ bool pkgProblemResolver::ResolveByKeepInternal() { pkgDepCache::ActionGroup group(Cache); unsigned long Size = Cache.Head().PackageCount; MakeScores(); /* We have to order the packages so that the broken fixing pass operates from highest score to lowest. This prevents problems when high score packages cause the removal of lower score packages that would cause the removal of even lower score packages. */ pkgCache::Package **PList = new pkgCache::Package *[Size]; pkgCache::Package **PEnd = PList; for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) *PEnd++ = I; This = this; qsort(PList,PEnd - PList,sizeof(*PList),&ScoreSort); if (_config->FindB("Debug::pkgProblemResolver::ShowScores",false) == true) { clog << "Show Scores" << endl; for (pkgCache::Package **K = PList; K != PEnd; K++) if (Scores[(*K)->ID] != 0) { pkgCache::PkgIterator Pkg(Cache,*K); clog << Scores[(*K)->ID] << ' ' << Pkg << std::endl; } } if (Debug == true) clog << "Entering ResolveByKeep" << endl; // Consider each broken package pkgCache::Package **LastStop = 0; for (pkgCache::Package **K = PList; K != PEnd; K++) { pkgCache::PkgIterator I(Cache,*K); if (Cache[I].InstallVer == 0) continue; if (InstOrNewPolicyBroken(I) == false) continue; /* Keep the package. If this works then great, otherwise we have to be significantly more agressive and manipulate its dependencies */ if ((Flags[I->ID] & Protected) == 0) { if (Debug == true) clog << "Keeping package " << I.FullName(false) << endl; Cache.MarkKeep(I, false, false); if (InstOrNewPolicyBroken(I) == false) { K = PList - 1; continue; } } // Isolate the problem dependencies for (pkgCache::DepIterator D = Cache[I].InstVerIter(Cache).DependsList(); D.end() == false;) { DepIterator Start; DepIterator End; D.GlobOr(Start,End); // We only worry about critical deps. if (End.IsCritical() != true) continue; // Dep is ok if ((Cache[End] & pkgDepCache::DepGInstall) == pkgDepCache::DepGInstall) continue; /* Hm, the group is broken.. I suppose the best thing to do is to is to try every combination of keep/not-keep for the set, but thats slow, and this never happens, just be conservative and assume the list of ors is in preference and keep till it starts to work. */ while (true) { if (Debug == true) clog << "Package " << I.FullName(false) << " " << Start << endl; // Look at all the possible provides on this package SPtrArray<pkgCache::Version *> VList = Start.AllTargets(); for (pkgCache::Version **V = VList; *V != 0; V++) { pkgCache::VerIterator Ver(Cache,*V); pkgCache::PkgIterator Pkg = Ver.ParentPkg(); // It is not keepable if (Cache[Pkg].InstallVer == 0 || Pkg->CurrentVer == 0) continue; if ((Flags[I->ID] & Protected) == 0) { if (Debug == true) clog << " Keeping Package " << Pkg.FullName(false) << " due to " << Start.DepType() << endl; Cache.MarkKeep(Pkg, false, false); } if (InstOrNewPolicyBroken(I) == false) break; } if (InstOrNewPolicyBroken(I) == false) break; if (Start == End) break; ++Start; } if (InstOrNewPolicyBroken(I) == false) break; } if (InstOrNewPolicyBroken(I) == true) continue; // Restart again. if (K == LastStop) return _error->Error("Internal Error, pkgProblemResolver::ResolveByKeep is looping on package %s.",I.FullName(false).c_str()); LastStop = K; K = PList - 1; } return true; } /*}}}*/ // ProblemResolver::InstallProtect - Install all protected packages /*{{{*/ // --------------------------------------------------------------------- /* This is used to make sure protected packages are installed */ void pkgProblemResolver::InstallProtect() { pkgDepCache::ActionGroup group(Cache); for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I) { if ((Flags[I->ID] & Protected) == Protected) { if ((Flags[I->ID] & ToRemove) == ToRemove) Cache.MarkDelete(I); else { // preserve the information whether the package was auto // or manually installed bool autoInst = (Cache[I].Flags & pkgCache::Flag::Auto); Cache.MarkInstall(I, false, 0, !autoInst); } } } } /*}}}*/ // PrioSortList - Sort a list of versions by priority /*{{{*/ // --------------------------------------------------------------------- /* This is ment to be used in conjunction with AllTargets to get a list of versions ordered by preference. */ static pkgCache *PrioCache; static int PrioComp(const void *A,const void *B) { pkgCache::VerIterator L(*PrioCache,*(pkgCache::Version **)A); pkgCache::VerIterator R(*PrioCache,*(pkgCache::Version **)B); if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential && (R.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential) return 1; if ((L.ParentPkg()->Flags & pkgCache::Flag::Essential) != pkgCache::Flag::Essential && (R.ParentPkg()->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential) return -1; if ((L.ParentPkg()->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important && (R.ParentPkg()->Flags & pkgCache::Flag::Important) != pkgCache::Flag::Important) return 1; if ((L.ParentPkg()->Flags & pkgCache::Flag::Important) != pkgCache::Flag::Important && (R.ParentPkg()->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important) return -1; if (L->Priority != R->Priority) return R->Priority - L->Priority; return strcmp(L.ParentPkg().Name(),R.ParentPkg().Name()); } void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List) { unsigned long Count = 0; PrioCache = &Cache; for (pkgCache::Version **I = List; *I != 0; I++) Count++; qsort(List,Count,sizeof(*List),PrioComp); } /*}}}*/ // ListUpdate - construct Fetcher and update the cache files /*{{{*/ // --------------------------------------------------------------------- /* This is a simple wrapper to update the cache. it will fetch stuff * from the network (or any other sources defined in sources.list) */ bool ListUpdate(pkgAcquireStatus &Stat, pkgSourceList &List, int PulseInterval) { pkgAcquire Fetcher; if (Fetcher.Setup(&Stat, _config->FindDir("Dir::State::Lists")) == false) return false; // Populate it with the source selection if (List.GetIndexes(&Fetcher) == false) return false; return AcquireUpdate(Fetcher, PulseInterval, true); } /*}}}*/ // AcquireUpdate - take Fetcher and update the cache files /*{{{*/ // --------------------------------------------------------------------- /* This is a simple wrapper to update the cache with a provided acquire * If you only need control over Status and the used SourcesList use * ListUpdate method instead. */ bool AcquireUpdate(pkgAcquire &Fetcher, int const PulseInterval, bool const RunUpdateScripts, bool const ListCleanup) { // Run scripts if (RunUpdateScripts == true) RunScripts("APT::Update::Pre-Invoke"); pkgAcquire::RunResult res; if(PulseInterval > 0) res = Fetcher.Run(PulseInterval); else res = Fetcher.Run(); if (res == pkgAcquire::Failed) return false; bool Failed = false; bool TransientNetworkFailure = false; for (pkgAcquire::ItemIterator I = Fetcher.ItemsBegin(); I != Fetcher.ItemsEnd(); ++I) { if ((*I)->Status == pkgAcquire::Item::StatDone) continue; (*I)->Finished(); ::URI uri((*I)->DescURI()); uri.User.clear(); uri.Password.clear(); string descUri = string(uri); _error->Warning(_("Failed to fetch %s %s\n"), descUri.c_str(), (*I)->ErrorText.c_str()); if ((*I)->Status == pkgAcquire::Item::StatTransientNetworkError) { TransientNetworkFailure = true; continue; } Failed = true; } // Clean out any old list files // Keep "APT::Get::List-Cleanup" name for compatibility, but // this is really a global option for the APT library now if (!TransientNetworkFailure && !Failed && ListCleanup == true && (_config->FindB("APT::Get::List-Cleanup",true) == true && _config->FindB("APT::List-Cleanup",true) == true)) { if (Fetcher.Clean(_config->FindDir("Dir::State::lists")) == false || Fetcher.Clean(_config->FindDir("Dir::State::lists") + "partial/") == false) // something went wrong with the clean return false; } if (TransientNetworkFailure == true) _error->Warning(_("Some index files failed to download. They have been ignored, or old ones used instead.")); else if (Failed == true) return _error->Error(_("Some index files failed to download. They have been ignored, or old ones used instead.")); // Run the success scripts if all was fine if (RunUpdateScripts == true) { if(!TransientNetworkFailure && !Failed) RunScripts("APT::Update::Post-Invoke-Success"); // Run the other scripts RunScripts("APT::Update::Post-Invoke"); } return true; } /*}}}*/