apt-pkg/algorithms.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: algorithms.h,v 1.10 2001/05/22 04:17:41 jgg Exp $
   4 /* ######################################################################
   5
   6    Algorithms - A set of misc algorithms
   7
   8    This simulate class displays what the ordering code has done and
   9    analyses it with a fresh new dependency cache. In this way we can
  10    see all of the effects of an upgrade run.
  11
  12    pkgDistUpgrade computes an upgrade that causes as many packages as
  13    possible to move to the newest verison.
  14
  15    pkgApplyStatus sets the target state based on the content of the status
  16    field in the status file. It is important to get proper crash recovery.
  17
  18    pkgFixBroken corrects a broken system so that it is in a sane state.
  19
  20    pkgAllUpgrade attempts to upgade as many packages as possible but
  21    without installing new packages.
  22
  23    The problem resolver class contains a number of complex algorithms
  24    to try to best-guess an upgrade state. It solves the problem of
  25    maximizing the number of install state packages while having no broken
  26    packages.
  27
  28    ##################################################################### */
  29                                                                         /*}}}*/
  30 #ifndef PKGLIB_ALGORITHMS_H
  31 #define PKGLIB_ALGORITHMS_H
  32
  33 #ifdef __GNUG__
  34 #pragma interface "apt-pkg/algorithms.h"
  35 #endif
  36
  37 #include <apt-pkg/packagemanager.h>
  38 #include <apt-pkg/depcache.h>
  39
  40 #include <iostream>
  41
  42 using std::ostream;
  43
  44 class pkgSimulate : public pkgPackageManager
  45 {
  46    protected:
  47
  48    class Policy : public pkgDepCache::Policy
  49    {
  50       pkgDepCache *Cache;
  51       public:
  52
  53       virtual VerIterator GetCandidateVer(PkgIterator Pkg)
  54       {
  55          return (*Cache)[Pkg].CandidateVerIter(*Cache);
  56       }
  57
  58       Policy(pkgDepCache *Cache) : Cache(Cache) {};
  59    };
  60
  61    unsigned char *Flags;
  62
  63    Policy iPolicy;
  64    pkgDepCache Sim;
  65
  66    // The Actuall installation implementation
  67    virtual bool Install(PkgIterator Pkg,string File);
  68    virtual bool Configure(PkgIterator Pkg);
  69    virtual bool Remove(PkgIterator Pkg,bool Purge);
  70
  71 private:
  72    void ShortBreaks();
  73    void Describe(PkgIterator iPkg,ostream &out,bool Current,bool Candidate);
  74
  75    public:
  76
  77    pkgSimulate(pkgDepCache *Cache);
  78 };
  79
  80 class pkgProblemResolver
  81 {
  82    pkgDepCache &Cache;
  83    typedef pkgCache::PkgIterator PkgIterator;
  84    typedef pkgCache::VerIterator VerIterator;
  85    typedef pkgCache::DepIterator DepIterator;
  86    typedef pkgCache::PrvIterator PrvIterator;
  87    typedef pkgCache::Version Version;
  88    typedef pkgCache::Package Package;
  89
  90    enum Flags {Protected = (1 << 0), PreInstalled = (1 << 1),
  91                Upgradable = (1 << 2), ReInstateTried = (1 << 3),
  92                ToRemove = (1 << 4)};
  93    signed short *Scores;
  94    unsigned char *Flags;
  95    bool Debug;
  96
  97    // Sort stuff
  98    static pkgProblemResolver *This;
  99    static int ScoreSort(const void *a,const void *b);
 100
 101    struct PackageKill
 102    {
 103       PkgIterator Pkg;
 104       DepIterator Dep;
 105    };
 106
 107    void MakeScores();
 108    bool DoUpgrade(pkgCache::PkgIterator Pkg);
 109
 110    public:
 111
 112    inline void Protect(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] |= Protected;};
 113    inline void Remove(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] |= ToRemove;};
 114    inline void Clear(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] &= ~(Protected | ToRemove);};
 115
 116    // Try to intelligently resolve problems by installing and removing packages
 117    bool Resolve(bool BrokenFix = false);
 118
 119    // Try to resolve problems only by using keep
 120    bool ResolveByKeep();
 121
 122    void InstallProtect();
 123
 124    pkgProblemResolver(pkgDepCache *Cache);
 125    ~pkgProblemResolver();
 126 };
 127
 128 bool pkgDistUpgrade(pkgDepCache &Cache);
 129 bool pkgApplyStatus(pkgDepCache &Cache);
 130 bool pkgFixBroken(pkgDepCache &Cache);
 131 bool pkgAllUpgrade(pkgDepCache &Cache);
 132 bool pkgMinimizeUpgrade(pkgDepCache &Cache);
 133
 134 void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List);
 135
 136 // mark all reachable packages, everything that is not reach can
 137 // be removed
 138 bool pkgMarkUsed(pkgDepCache &Cache);
 139
 140 #endif