apt-pkg/edsp/edspsystem.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 /* ######################################################################
   4
   5    This system provides the abstraction to use the scenario file as the
   6    only source of package information to be able to feed the created file
   7    back to APT for its own consumption (eat your own dogfood).
   8
   9    ##################################################################### */
  10                                                                         /*}}}*/
  11 // Include Files                                                        /*{{{*/
  12 #include <config.h>
  13
  14 #include <apt-pkg/configuration.h>
  15 #include <apt-pkg/debversion.h>
  16 #include <apt-pkg/edspindexfile.h>
  17 #include <apt-pkg/edspsystem.h>
  18 #include <apt-pkg/pkgcache.h>
  19 #include <apt-pkg/cacheiterators.h>
  20 #include <apt-pkg/fileutl.h>
  21
  22 #include <stddef.h>
  23 #include <unistd.h>
  24
  25 #include <string>
  26 #include <vector>
  27
  28                                                                         /*}}}*/
  29
  30 class edspSystemPrivate {
  31    std::string tempDir;
  32    std::string tempStatesFile;
  33    std::string tempPrefsFile;
  34
  35 public:
  36    edspSystemPrivate() {}
  37
  38    void Initialize(Configuration &Cnf)
  39    {
  40       DeInitialize();
  41       Cnf.Set("Dir::State::extended_states", "/dev/null");
  42       Cnf.Set("Dir::Etc::preferences", "/dev/null");
  43       std::string const tmp = GetTempDir();
  44       char tmpname[100];
  45       snprintf(tmpname, sizeof(tmpname), "%s/apt-edsp-solver-XXXXXX", tmp.c_str());
  46       if (NULL == mkdtemp(tmpname))
  47          return;
  48       tempDir = tmpname;
  49       tempStatesFile = flCombine(tempDir, "extended_states");
  50       Cnf.Set("Dir::State::extended_states", tempStatesFile);
  51       tempPrefsFile = flCombine(tempDir, "apt_preferences");
  52       Cnf.Set("Dir::Etc::preferences", tempPrefsFile);
  53    }
  54
  55    void DeInitialize()
  56    {
  57       if (tempDir.empty())
  58          return;
  59
  60       unlink(tempStatesFile.c_str());
  61       unlink(tempPrefsFile.c_str());
  62       rmdir(tempDir.c_str());
  63    }
  64
  65    ~edspSystemPrivate() { DeInitialize(); }
  66 };
  67 // System::edspSystem - Constructor                                     /*{{{*/
  68 edspSystem::edspSystem() : pkgSystem("Debian APT solver interface", &debVS), d(new edspSystemPrivate()), StatusFile(NULL)
  69 {
  70 }
  71                                                                         /*}}}*/
  72 // System::~debSystem - Destructor                                      /*{{{*/
  73 edspSystem::~edspSystem()
  74 {
  75    delete StatusFile;
  76    delete d;
  77 }
  78                                                                         /*}}}*/
  79 // System::Lock - Get the lock                                          /*{{{*/
  80 bool edspSystem::Lock()
  81 {
  82    return true;
  83 }
  84                                                                         /*}}}*/
  85 // System::UnLock - Drop a lock                                         /*{{{*/
  86 bool edspSystem::UnLock(bool /*NoErrors*/)
  87 {
  88    return true;
  89 }
  90                                                                         /*}}}*/
  91 // System::CreatePM - Create the underlying package manager             /*{{{*/
  92 // ---------------------------------------------------------------------
  93 /* we can't use edsp input as input for real installations - just a
  94    simulation can work, but everything else will fail bigtime */
  95 pkgPackageManager *edspSystem::CreatePM(pkgDepCache * /*Cache*/) const
  96 {
  97    return NULL;
  98 }
  99                                                                         /*}}}*/
 100 // System::Initialize - Setup the configuration space..                 /*{{{*/
 101 bool edspSystem::Initialize(Configuration &Cnf)
 102 {
 103    d->Initialize(Cnf);
 104    Cnf.Set("Dir::Etc::preferencesparts", "/dev/null");
 105    Cnf.Set("Dir::State::status","/dev/null");
 106    Cnf.Set("Dir::State::lists","/dev/null");
 107
 108    Cnf.Set("Debug::NoLocking", "true");
 109    Cnf.Set("APT::Get::Simulate", "true");
 110
 111    if (StatusFile) {
 112      delete StatusFile;
 113      StatusFile = 0;
 114    }
 115    return true;
 116 }
 117                                                                         /*}}}*/
 118 // System::ArchiveSupported - Is a file format supported                /*{{{*/
 119 bool edspSystem::ArchiveSupported(const char * /*Type*/)
 120 {
 121    return false;
 122 }
 123                                                                         /*}}}*/
 124 // System::Score - Never use the EDSP system automatically              /*{{{*/
 125 signed edspSystem::Score(Configuration const &)
 126 {
 127    return -1000;
 128 }
 129                                                                         /*}}}*/
 130 bool edspSystem::AddStatusFiles(std::vector<pkgIndexFile *> &List)      /*{{{*/
 131 {
 132    if (StatusFile == 0)
 133    {
 134       if (_config->Find("edsp::scenario", "") == "/nonexistent/stdin")
 135          StatusFile = new edspIndex("/nonexistent/stdin");
 136       else
 137          StatusFile = new edspIndex(_config->FindFile("edsp::scenario"));
 138    }
 139    List.push_back(StatusFile);
 140    return true;
 141 }
 142                                                                         /*}}}*/
 143 // System::FindIndex - Get an index file for status files               /*{{{*/
 144 bool edspSystem::FindIndex(pkgCache::PkgFileIterator File,
 145                           pkgIndexFile *&Found) const
 146 {
 147    if (StatusFile == 0)
 148       return false;
 149    if (StatusFile->FindInCache(*File.Cache()) == File)
 150    {
 151       Found = StatusFile;
 152       return true;
 153    }
 154
 155    return false;
 156 }
 157                                                                         /*}}}*/
 158
 159 APT_HIDDEN edspSystem edspSys;