apt-pkg/deb/debsystem.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: debsystem.cc,v 1.4 2004/01/26 17:01:53 mdz Exp $
   4 /* ######################################################################
   5
   6    System - Abstraction for running on different systems.
   7
   8    Basic general structure..
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #include <apt-pkg/debsystem.h>
  14 #include <apt-pkg/debversion.h>
  15 #include <apt-pkg/debindexfile.h>
  16 #include <apt-pkg/dpkgpm.h>
  17 #include <apt-pkg/configuration.h>
  18 #include <apt-pkg/error.h>
  19 #include <apt-pkg/fileutl.h>
  20 #include <apti18n.h>
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23 #include <dirent.h>
  24 #include <errno.h>
  25                                                                         /*}}}*/
  26
  27 debSystem debSys;
  28
  29 // System::debSystem - Constructor                                      /*{{{*/
  30 // ---------------------------------------------------------------------
  31 /* */
  32 debSystem::debSystem()
  33 {
  34    LockFD = -1;
  35    LockCount = 0;
  36    StatusFile = 0;
  37
  38    Label = "Debian dpkg interface";
  39    VS = &debVS;
  40 }
  41                                                                         /*}}}*/
  42 // System::~debSystem - Destructor                                      /*{{{*/
  43 // ---------------------------------------------------------------------
  44 /* */
  45 debSystem::~debSystem()
  46 {
  47    delete StatusFile;
  48 }
  49                                                                         /*}}}*/
  50 // System::Lock - Get the lock                                          /*{{{*/
  51 // ---------------------------------------------------------------------
  52 /* This mirrors the operations dpkg does when it starts up. Note the
  53    checking of the updates directory. */
  54 bool debSystem::Lock()
  55 {
  56    // Disable file locking
  57    if (_config->FindB("Debug::NoLocking",false) == true || LockCount > 1)
  58    {
  59       LockCount++;
  60       return true;
  61    }
  62
  63    // Create the lockfile
  64    string AdminDir = flNotFile(_config->Find("Dir::State::status"));
  65    LockFD = GetLock(AdminDir + "lock");
  66    if (LockFD == -1)
  67    {
  68       if (errno == EACCES || errno == EAGAIN)
  69          return _error->Error(_("Unable to lock the administration directory (%s), "
  70                                 "is another process using it?"),AdminDir.c_str());
  71       else
  72          return _error->Error(_("Unable to lock the administration directory (%s), "
  73                                 "are you root?"),AdminDir.c_str());
  74    }
  75
  76    // See if we need to abort with a dirty journal
  77    if (CheckUpdates() == true)
  78    {
  79       close(LockFD);
  80       LockFD = -1;
  81       const char *cmd;
  82       if (getenv("SUDO_USER") != NULL)
  83          cmd = "sudo dpkg --configure -a";
  84       else
  85          cmd = "dpkg --configure -a";
  86       // TRANSLATORS: the %s contains the recovery command, usually
  87       //              dpkg --configure -a
  88       return _error->Error(_("dpkg was interrupted, you must manually "
  89                              "run '%s' to correct the problem. "), cmd);
  90    }
  91
  92          LockCount++;
  93
  94    return true;
  95 }
  96                                                                         /*}}}*/
  97 // System::UnLock - Drop a lock                                         /*{{{*/
  98 // ---------------------------------------------------------------------
  99 /* */
 100 bool debSystem::UnLock(bool NoErrors)
 101 {
 102    if (LockCount == 0 && NoErrors == true)
 103       return false;
 104
 105    if (LockCount < 1)
 106       return _error->Error(_("Not locked"));
 107    if (--LockCount == 0)
 108    {
 109       close(LockFD);
 110       LockCount = 0;
 111    }
 112
 113    return true;
 114 }
 115                                                                         /*}}}*/
 116 // System::CheckUpdates - Check if the updates dir is dirty             /*{{{*/
 117 // ---------------------------------------------------------------------
 118 /* This does a check of the updates directory (dpkg journal) to see if it has
 119    any entries in it. */
 120 bool debSystem::CheckUpdates()
 121 {
 122    // Check for updates.. (dirty)
 123    string File = flNotFile(_config->Find("Dir::State::status")) + "updates/";
 124    DIR *DirP = opendir(File.c_str());
 125    if (DirP == 0)
 126       return false;
 127
 128    /* We ignore any files that are not all digits, this skips .,.. and
 129       some tmp files dpkg will leave behind.. */
 130    bool Damaged = false;
 131    for (struct dirent *Ent = readdir(DirP); Ent != 0; Ent = readdir(DirP))
 132    {
 133       Damaged = true;
 134       for (unsigned int I = 0; Ent->d_name[I] != 0; I++)
 135       {
 136          // Check if its not a digit..
 137          if (isdigit(Ent->d_name[I]) == 0)
 138          {
 139             Damaged = false;
 140             break;
 141          }
 142       }
 143       if (Damaged == true)
 144          break;
 145    }
 146    closedir(DirP);
 147
 148    return Damaged;
 149 }
 150                                                                         /*}}}*/
 151 // System::CreatePM - Create the underlying package manager             /*{{{*/
 152 // ---------------------------------------------------------------------
 153 /* */
 154 pkgPackageManager *debSystem::CreatePM(pkgDepCache *Cache) const
 155 {
 156    return new pkgDPkgPM(Cache);
 157 }
 158                                                                         /*}}}*/
 159 // System::Initialize - Setup the configuration space..                 /*{{{*/
 160 // ---------------------------------------------------------------------
 161 /* These are the Debian specific configuration variables.. */
 162 bool debSystem::Initialize(Configuration &Cnf)
 163 {
 164    /* These really should be jammed into a generic 'Local Database' engine
 165       which is yet to be determined. The functions in pkgcachegen should
 166       be the only users of these */
 167    Cnf.CndSet("Dir::State::userstatus","status.user"); // Defunct
 168    Cnf.CndSet("Dir::State::status","/var/lib/dpkg/status");
 169    Cnf.CndSet("Dir::Bin::dpkg","/usr/bin/dpkg");
 170
 171    if (StatusFile) {
 172      delete StatusFile;
 173      StatusFile = 0;
 174    }
 175
 176    return true;
 177 }
 178                                                                         /*}}}*/
 179 // System::ArchiveSupported - Is a file format supported                /*{{{*/
 180 // ---------------------------------------------------------------------
 181 /* The standard name for a deb is 'deb'.. There are no seperate versions
 182    of .deb to worry about.. */
 183 bool debSystem::ArchiveSupported(const char *Type)
 184 {
 185    if (strcmp(Type,"deb") == 0)
 186       return true;
 187    return false;
 188 }
 189                                                                         /*}}}*/
 190 // System::Score - Determine how 'Debiany' this sys is..                /*{{{*/
 191 // ---------------------------------------------------------------------
 192 /* We check some files that are sure tell signs of this being a Debian
 193    System.. */
 194 signed debSystem::Score(Configuration const &Cnf)
 195 {
 196    signed Score = 0;
 197    if (FileExists(Cnf.FindFile("Dir::State::status","/var/lib/dpkg/status")) == true)
 198        Score += 10;
 199    if (FileExists(Cnf.FindFile("Dir::Bin::dpkg","/usr/bin/dpkg")) == true)
 200       Score += 10;
 201    if (FileExists("/etc/debian_version") == true)
 202       Score += 10;
 203    return Score;
 204 }
 205                                                                         /*}}}*/
 206 // System::AddStatusFiles - Register the status files                   /*{{{*/
 207 // ---------------------------------------------------------------------
 208 /* */
 209 bool debSystem::AddStatusFiles(vector<pkgIndexFile *> &List)
 210 {
 211    if (StatusFile == 0)
 212       StatusFile = new debStatusIndex(_config->FindFile("Dir::State::status"));
 213    List.push_back(StatusFile);
 214    return true;
 215 }
 216                                                                         /*}}}*/
 217 // System::FindIndex - Get an index file for status files               /*{{{*/
 218 // ---------------------------------------------------------------------
 219 /* */
 220 bool debSystem::FindIndex(pkgCache::PkgFileIterator File,
 221                           pkgIndexFile *&Found) const
 222 {
 223    if (StatusFile == 0)
 224       return false;
 225    if (StatusFile->FindInCache(*File.Cache()) == File)
 226    {
 227       Found = StatusFile;
 228       return true;
 229    }
 230
 231    return false;
 232 }
 233                                                                         /*}}}*/