depcache.h

// -*- mode: c++; mode: fold -*-
// Description                                                          /*{{{*/
/* ######################################################################
 
   DepCache - Dependency Extension data for the cache
   
   This class stores the cache data and a set of extension structures for
   monitoring the current state of all the packages. It also generates and
   caches the 'install' state of many things. This refers to the state of the
   package after an install has been run.
 
   The StateCache::State field can be -1,0,1,2 which is <,=,>,no current.
   StateCache::Mode is which of the 3 fields is active.
   
   This structure is important to support the readonly status of the cache 
   file. When the data is saved the cache will be refereshed from our 
   internal rep and written to disk. Then the actual persistent data
   files will be put on the disk.
 
   Each dependency is compared against 3 target versions to produce to
   3 dependency results.
     Now - Compared using the Currently install version
     Install - Compared using the install version (final state)
     CVer - (Candidate Version) Compared using the Candidate Version
   The candidate and now results are used to decide whether a package
   should be automatically installed or if it should be left alone.
   
   Remember, the Candidate Version is selected based on the distribution
   settings for the Package. The Install Version is selected based on the
   state (Delete, Keep, Install) field and can be either the Current Version
   or the Candidate version.
   
   The Candidate version is what is shown the 'Install Version' field.
   
   ##################################################################### */
                                                                        /*}}}*/
#ifndef PKGLIB_DEPCACHE_H
#define PKGLIB_DEPCACHE_H
 
#include <apt-pkg/configuration.h>
#include <apt-pkg/macros.h>
#include <apt-pkg/pkgcache.h>
 
#include <cstddef>
 
#include <list>
#include <memory>
#include <string>
#include <string_view>
#include <utility>
 
 
class OpProgress;
class pkgVersioningSystem;
namespace APT
{
template <class Container>
class PackageContainer;
using PackageVector = PackageContainer<std::vector<pkgCache::PkgIterator>>;
} // namespace APT
 
class APT_PUBLIC pkgDepCache : protected pkgCache::Namespace
{
   public:
 
   class APT_PUBLIC InRootSetFunc
   {
   public:
     virtual bool InRootSet(const pkgCache::PkgIterator &/*pkg*/) {return false;};
     virtual ~InRootSetFunc() {};
   };
 
   private:
   bool MarkRequired(InRootSetFunc &rootFunc);
 
   bool Sweep();
 
   public:
   
   // These flags are used in DepState
   enum DepFlags {DepNow = (1 << 0),DepInstall = (1 << 1),DepCVer = (1 << 2),
                  DepGNow = (1 << 3),DepGInstall = (1 << 4),DepGCVer = (1 << 5)};
 
   // These flags are used in StateCache::DepState
   enum DepStateFlags {DepNowPolicy = (1 << 0), DepNowMin = (1 << 1),
                       DepInstPolicy = (1 << 2), DepInstMin = (1 << 3),
                       DepCandPolicy = (1 << 4), DepCandMin = (1 << 5)};
   
   // These flags are used in StateCache::iFlags
   enum InternalFlags {AutoKept = (1 << 0), Purge = (1 << 1), ReInstall = (1 << 2), Protected = (1 << 3)};
      
   enum VersionTypes {NowVersion, InstallVersion, CandidateVersion};
   enum ModeList {ModeDelete = 0, ModeKeep = 1, ModeInstall = 2, ModeGarbage = 3};
 
   class APT_PUBLIC ActionGroup
   {
       void * const d;
       pkgDepCache &cache;
 
       bool released;
 
       APT_HIDDEN ActionGroup(const ActionGroup &other);
   public:
       explicit ActionGroup(pkgDepCache &cache);
 
       void release();
 
       virtual ~ActionGroup();
   };
 
   class APT_PUBLIC DefaultRootSetFunc : public InRootSetFunc, public Configuration::MatchAgainstConfig
   {
   public:
     DefaultRootSetFunc() : Configuration::MatchAgainstConfig("APT::NeverAutoRemove") {};
     ~DefaultRootSetFunc() override = default;
 
     bool InRootSet(const pkgCache::PkgIterator &pkg) override { return pkg.end() == false && Match(pkg.Name()); };
   };
 
   struct APT_PUBLIC StateCache
   {
      // text versions of the two version fields
      const char *CandVersion;
      const char *CurVersion;
 
      // Pointer to the candidate install version. 
      Version *CandidateVer;
 
      // Pointer to the install version.
      Version *InstallVer;
      
      // Copy of Package::Flags
      unsigned short Flags;
      unsigned short iFlags;           // Internal flags
 
      bool Marked;
 
      bool Garbage;
 
      // Various tree indicators
      signed char Status;              // -1,0,1,2
      unsigned char Mode;              // ModeList
      unsigned char DepState;          // DepState Flags
 
      // Update of candidate version
      void Update(PkgIterator Pkg,pkgCache &Cache);
      
      // Various test members for the current status of the package
      inline bool NewInstall() const {return Status == 2 && Mode == ModeInstall;};
      inline bool Delete() const {return Mode == ModeDelete;};
      inline bool Purge() const {return Delete() == true && (iFlags & pkgDepCache::Purge) == pkgDepCache::Purge; };
      inline bool Keep() const {return Mode == ModeKeep;};
      inline bool Protect() const {return (iFlags & Protected) == Protected;};
      inline bool Upgrade() const {return Status > 0 && Mode == ModeInstall;};
      inline bool Upgradable() const {return Status >= 1 && CandidateVer != NULL;};
      inline bool Downgrade() const {return Status < 0 && Mode == ModeInstall;};
      inline bool Held() const {return Status != 0 && Keep();};
      inline bool NowBroken() const {return (DepState & DepNowMin) != DepNowMin;};
      inline bool NowPolicyBroken() const {return (DepState & DepNowPolicy) != DepNowPolicy;};
      inline bool InstBroken() const {return (DepState & DepInstMin) != DepInstMin;};
      inline bool InstPolicyBroken() const {return (DepState & DepInstPolicy) != DepInstPolicy;};
      inline bool Install() const {return Mode == ModeInstall;};
      inline bool ReInstall() const {return Delete() == false && (iFlags & pkgDepCache::ReInstall) == pkgDepCache::ReInstall;};
      inline VerIterator InstVerIter(pkgCache &Cache)
                {return VerIterator(Cache,InstallVer);};
      inline VerIterator CandidateVerIter(pkgCache &Cache)
                {return VerIterator(Cache,CandidateVer);};
   };
   
   // Helper functions
   void BuildGroupOrs(VerIterator const &V);
   void UpdateVerState(PkgIterator const &Pkg);
 
   // User Policy control
   class APT_PUBLIC Policy
   {
      public:
      Policy() {
         InstallRecommends = _config->FindB("APT::Install-Recommends", false);
         InstallSuggests = _config->FindB("APT::Install-Suggests", false);
      }
 
      virtual VerIterator GetCandidateVer(PkgIterator const &Pkg);
      virtual bool IsImportantDep(DepIterator const &Dep) const;
      virtual signed short GetPriority(PkgIterator const &Pkg);
      virtual signed short GetPriority(VerIterator const &Ver, bool ConsiderFiles=true);
      virtual signed short GetPriority(PkgFileIterator const &File);
 
      virtual ~Policy() {};
 
      private:
      bool InstallRecommends;
      bool InstallSuggests;
   };
 
   class APT_PUBLIC Transaction final
   {
      struct Private;
      std::unique_ptr<Private> d;
 
      public:
      enum class Behavior
      {
         COMMIT,
         ROLLBACK,
         AUTO,
      };
 
      explicit Transaction(pkgDepCache &cache, Behavior behavior);
      void commit();
      void rollback();
      void temporaryRollback();
      ~Transaction();
   };
 
   private:
   int group_level;
 
   friend class ActionGroup;
   friend class Transaction;
 
   public:
   int IncreaseActionGroupLevel();
   int DecreaseActionGroupLevel();
 
   protected:
 
   // State information
   pkgCache *Cache;
   StateCache *PkgState;
   unsigned char *DepState;
 
   signed long long iUsrSize;
   unsigned long long iDownloadSize;
   unsigned long iInstCount;
   unsigned long iDelCount;
   unsigned long iKeepCount;
   unsigned long iBrokenCount;
   unsigned long iPolicyBrokenCount;
   unsigned long iBadCount;
 
   bool DebugMarker;
   bool DebugAutoInstall;
 
   Policy *delLocalPolicy;           // For memory clean up..
   Policy *LocalPolicy;
   
   // Check for a matching provides
   bool CheckDep(DepIterator const &Dep,int const Type,PkgIterator &Res);
   inline bool CheckDep(DepIterator const &Dep,int const Type)
   {
      PkgIterator Res(*this,0);
      return CheckDep(Dep,Type,Res);
   }
   
   // Computes state information for deps and versions (w/o storing)
   unsigned char DependencyState(DepIterator const &D);
   unsigned char VersionState(DepIterator D,unsigned char const Check,
                              unsigned char const SetMin,
                              unsigned char const SetPolicy) const;
 
   // Recalculates various portions of the cache, call after changing something
   void Update(DepIterator Dep);           // Mostly internal
   void Update(PkgIterator const &P);
   
   // Count manipulators
   void AddSizes(const PkgIterator &Pkg, bool const Invert = false);
   inline void RemoveSizes(const PkgIterator &Pkg) {AddSizes(Pkg, true);};
   void AddStates(const PkgIterator &Pkg, bool const Invert = false);
   inline void RemoveStates(const PkgIterator &Pkg) {AddStates(Pkg,true);};
   
   public:
 
   // Legacy.. We look like a pkgCache
   inline operator pkgCache &() {return *Cache;};
   inline Header &Head() {return *Cache->HeaderP;};
   inline GrpIterator GrpBegin() {return Cache->GrpBegin();};
   inline PkgIterator PkgBegin() {return Cache->PkgBegin();};
   inline GrpIterator FindGrp(std::string_view Name) {return Cache->FindGrp(Name);};
   inline PkgIterator FindPkg(std::string_view Name) {return Cache->FindPkg(Name);};
   inline PkgIterator FindPkg(std::string_view Name, std::string_view Arch) {return Cache->FindPkg(Name, Arch);};
 
   inline pkgCache &GetCache() {return *Cache;};
   inline pkgVersioningSystem &VS() {return *Cache->VS;};
 
   inline bool IsImportantDep(DepIterator Dep) const {return LocalPolicy->IsImportantDep(Dep);};
   inline Policy &GetPolicy() {return *LocalPolicy;};
   
   // Accessors
   inline StateCache &operator [](PkgIterator const &I) {return PkgState[I->ID];};
   inline StateCache &operator [](PkgIterator const &I) const {return PkgState[I->ID];};
   inline unsigned char &operator [](DepIterator const &I) {return DepState[I->ID];};
   inline unsigned char const &operator [](DepIterator const &I) const {return DepState[I->ID];};
 
   virtual InRootSetFunc *GetRootSetFunc();
 
   InRootSetFunc *GetCachedRootSetFunc() APT_HIDDEN;
 
   virtual bool MarkFollowsRecommends();
 
   virtual bool MarkFollowsSuggests();
 
   bool MarkAndSweep(InRootSetFunc &rootFunc);
   bool MarkAndSweep();
 
   bool PhasingApplied(PkgIterator Pkg) const;
 
   // @{
   bool MarkKeep(PkgIterator const &Pkg, bool Soft = false,
                 bool FromUser = true, unsigned long Depth = 0);
   bool MarkDelete(PkgIterator const &Pkg, bool MarkPurge = false,
                   unsigned long Depth = 0, bool FromUser = true);
   bool MarkInstall(PkgIterator const &Pkg,bool AutoInst = true,
                    unsigned long Depth = 0, bool FromUser = true,
                    bool ForceImportantDeps = false);
   void MarkProtected(PkgIterator const &Pkg) { PkgState[Pkg->ID].iFlags |= Protected; };
 
   void SetReInstall(PkgIterator const &Pkg,bool To);
 
   pkgCache::VerIterator GetCandidateVersion(pkgCache::PkgIterator const &Pkg);
   void SetCandidateVersion(VerIterator TargetVer);
   bool SetCandidateRelease(pkgCache::VerIterator TargetVer,
                                std::string const &TargetRel);
   bool SetCandidateRelease(pkgCache::VerIterator TargetVer,
                            std::string const &TargetRel,
                            std::list<std::pair<pkgCache::VerIterator, pkgCache::VerIterator> > &Changed);
 
   void MarkAuto(const PkgIterator &Pkg, bool Auto);
   // @}
 
   virtual bool IsInstallOk(const PkgIterator &Pkg,bool AutoInst = true,
                            unsigned long Depth = 0, bool FromUser = true);
 
   virtual bool IsDeleteOk(const PkgIterator &Pkg,bool MarkPurge = false,
                            unsigned long Depth = 0, bool FromUser = true);
 
   // read persistent states
   bool readStateFile(OpProgress * const prog);
   bool writeStateFile(OpProgress * const prog, bool const InstalledOnly=true);
   
   // Size queries
   inline signed long long UsrSize() {return iUsrSize;};
   inline unsigned long long DebSize() {return iDownloadSize;};
   inline unsigned long DelCount() {return iDelCount;};
   inline unsigned long KeepCount() {return iKeepCount;};
   inline unsigned long InstCount() {return iInstCount;};
   unsigned long UpgradeCount();
   inline unsigned long BrokenCount() {return iBrokenCount;};
   inline unsigned long PolicyBrokenCount() {return iPolicyBrokenCount;};
   inline unsigned long BadCount() {return iBadCount;};
 
   bool Init(OpProgress * const Prog);
   // Generate all state information
   void Update(OpProgress * const Prog = 0);
 
   pkgDepCache(pkgCache * const Cache,Policy * const Plcy = 0);
   virtual ~pkgDepCache();
 
   bool CheckConsistency(char const *const msgtag = "");
#ifdef APT_COMPILING_APT
   unsigned long long BootSize(bool initrdOnly);
#endif
   protected:
   // methods call by IsInstallOk
   bool IsInstallOkMultiArchSameVersionSynced(PkgIterator const &Pkg,
         bool const AutoInst, unsigned long const Depth, bool const FromUser);
   bool IsInstallOkDependenciesSatisfiableByCandidates(PkgIterator const &Pkg,
      bool const AutoInst, unsigned long const Depth, bool const FromUser);
 
   // methods call by IsDeleteOk
   bool IsDeleteOkProtectInstallRequests(PkgIterator const &Pkg,
         bool const rPurge, unsigned long const Depth, bool const FromUser);
 
   private:
   struct Private;
   Private *const d;
 
   APT_HIDDEN bool MarkInstall_StateChange(PkgIterator const &Pkg, bool AutoInst, bool FromUser);
   APT_HIDDEN bool MarkInstall_DiscardInstall(PkgIterator const &Pkg);
 
   APT_HIDDEN void PerformDependencyPass(OpProgress * const Prog);
};
 
#endif