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    void ShortBreaks();
  71    void Describe(PkgIterator iPkg,ostream &out,bool Now);
  72
  73    public:
  74
  75    pkgSimulate(pkgDepCache *Cache);
  76 };
  77
  78 class pkgProblemResolver
  79 {
  80    pkgDepCache &Cache;
  81    typedef pkgCache::PkgIterator PkgIterator;
  82    typedef pkgCache::VerIterator VerIterator;
  83    typedef pkgCache::DepIterator DepIterator;
  84    typedef pkgCache::PrvIterator PrvIterator;
  85    typedef pkgCache::Version Version;
  86    typedef pkgCache::Package Package;
  87
  88    enum Flags {Protected = (1 << 0), PreInstalled = (1 << 1),
  89                Upgradable = (1 << 2), ReInstateTried = (1 << 3),
  90                ToRemove = (1 << 4)};
  91    signed short *Scores;
  92    unsigned char *Flags;
  93    bool Debug;
  94
  95    // Sort stuff
  96    static pkgProblemResolver *This;
  97    static int ScoreSort(const void *a,const void *b);
  98
  99    struct PackageKill
 100    {
 101       PkgIterator Pkg;
 102       DepIterator Dep;
 103    };
 104
 105    void MakeScores();
 106    bool DoUpgrade(pkgCache::PkgIterator Pkg);
 107
 108    public:
 109
 110    inline void Protect(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] |= Protected;};
 111    inline void Remove(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] |= ToRemove;};
 112    inline void Clear(pkgCache::PkgIterator Pkg) {Flags[Pkg->ID] &= ~(Protected | ToRemove);};
 113
 114    // Try to intelligently resolve problems by installing and removing packages
 115    bool Resolve(bool BrokenFix = false);
 116
 117    // Try to resolve problems only by using keep
 118    bool ResolveByKeep();
 119
 120    void InstallProtect();
 121
 122    pkgProblemResolver(pkgDepCache *Cache);
 123    ~pkgProblemResolver();
 124 };
 125
 126 bool pkgDistUpgrade(pkgDepCache &Cache);
 127 bool pkgApplyStatus(pkgDepCache &Cache);
 128 bool pkgFixBroken(pkgDepCache &Cache);
 129 bool pkgAllUpgrade(pkgDepCache &Cache);
 130 bool pkgMinimizeUpgrade(pkgDepCache &Cache);
 131
 132 void pkgPrioSortList(pkgCache &Cache,pkgCache::Version **List);
 133
 134 #endif