apt-pkg/deb/dpkginit.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: dpkginit.cc,v 1.3 1999/07/26 17:46:08 jgg Exp $
   4 /* ######################################################################
   5
   6    DPKG init - Initialize the dpkg stuff
   7
   8    This class provides the locking mechanism used by dpkg for its
   9    database area. It does the proper consistency checks and acquires the
  10    correct kind of lock.
  11
  12    ##################################################################### */
  13                                                                         /*}}}*/
  14 // Includes                                                             /*{{{*/
  15 #ifdef __GNUG__
  16 #pragma implementation "apt-pkg/dpkginit.h"
  17 #endif
  18 #include <apt-pkg/dpkginit.h>
  19 #include <apt-pkg/error.h>
  20 #include <apt-pkg/configuration.h>
  21 #include <apt-pkg/fileutl.h>
  22
  23 #include <sys/types.h>
  24 #include <unistd.h>
  25 #include <dirent.h>
  26                                                                         /*}}}*/
  27
  28 // DpkgLock::pkgDpkgLock - Constructor                                  /*{{{*/
  29 // ---------------------------------------------------------------------
  30 /* */
  31 pkgDpkgLock::pkgDpkgLock(bool WithUpdates)
  32 {
  33    LockFD = -1;
  34    GetLock(WithUpdates);
  35 }
  36                                                                         /*}}}*/
  37 // DpkgLock::~pkgDpkgLock - Destructor                                  /*{{{*/
  38 // ---------------------------------------------------------------------
  39 /* */
  40 pkgDpkgLock::~pkgDpkgLock()
  41 {
  42    Close();
  43 }
  44                                                                         /*}}}*/
  45 // DpkgLock::GetLock - Get the lock                                     /*{{{*/
  46 // ---------------------------------------------------------------------
  47 /* This mirrors the operations dpkg does when it starts up. Note the
  48    checking of the updates directory. */
  49 bool pkgDpkgLock::GetLock(bool WithUpdates)
  50 {
  51    // Disable file locking
  52    if (_config->FindB("Debug::NoLocking",false) == true)
  53       return true;
  54
  55    Close();
  56
  57    // Create the lockfile
  58    string AdminDir = flNotFile(_config->Find("Dir::State::status"));
  59    LockFD = ::GetLock(AdminDir + "lock");
  60    if (LockFD == -1)
  61       return _error->Error("Unable to lock the administration directory, "
  62                            "are you root?");
  63
  64    // See if we need to abort with a dirty journal
  65    if (WithUpdates == true && CheckUpdates() == false)
  66    {
  67       Close();
  68       return _error->Error("dpkg was interrupted, you must manually "
  69                            "run 'dpkg --configure -a' to correct the problem. ");
  70    }
  71
  72    return true;
  73 }
  74                                                                         /*}}}*/
  75 // DpkgLock::Close - Close the lock                                     /*{{{*/
  76 // ---------------------------------------------------------------------
  77 /* */
  78 void pkgDpkgLock::Close()
  79 {
  80    close(LockFD);
  81    LockFD = -1;
  82 }
  83                                                                         /*}}}*/
  84 // DpkgLock::CheckUpdates - Check if the updates dir is dirty           /*{{{*/
  85 // ---------------------------------------------------------------------
  86 /* This does a check of the updates directory to see if it has any entries
  87    in it. */
  88 bool pkgDpkgLock::CheckUpdates()
  89 {
  90    // Check for updates.. (dirty)
  91    string File = flNotFile(_config->Find("Dir::State::status")) + "updates/";
  92    DIR *DirP = opendir(File.c_str());
  93    if (DirP == 0)
  94       return true;
  95
  96    /* We ignore any files that are not all digits, this skips .,.. and
  97       some tmp files dpkg will leave behind.. */
  98    bool Damaged = false;
  99    for (struct dirent *Ent = readdir(DirP); Ent != 0; Ent = readdir(DirP))
 100    {
 101       Damaged = true;
 102       for (unsigned int I = 0; Ent->d_name[I] != 0; I++)
 103       {
 104          // Check if its not a digit..
 105          if (isdigit(Ent->d_name[I]) == 0)
 106          {
 107             Damaged = false;
 108             break;
 109          }
 110       }
 111       if (Damaged == true)
 112          break;
 113    }
 114    closedir(DirP);
 115
 116    return Damaged;
 117 }
 118                                                                         /*}}}*/
 119