apt-inst/deb/dpkgdb.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: dpkgdb.cc,v 1.7.2.1 2004/01/16 18:58:50 mdz Exp $
   4 /* ######################################################################
   5
   6    DPKGv1 Database Implemenation
   7
   8    This class provides parsers and other implementations for the DPKGv1
   9    database. It reads the diversion file, the list files and the status
  10    file to build both the list of currently installed files and the
  11    currently installed package list.
  12
  13    ##################################################################### */
  14                                                                         /*}}}*/
  15 // Include Files                                                        /*{{{*/
  16 #ifdef __GNUG__
  17 #pragma implementation "apt-pkg/dpkgdb.h"
  18 #endif
  19
  20 #include <apt-pkg/dpkgdb.h>
  21 #include <apt-pkg/configuration.h>
  22 #include <apt-pkg/error.h>
  23 #include <apt-pkg/progress.h>
  24 #include <apt-pkg/tagfile.h>
  25 #include <apt-pkg/strutl.h>
  26
  27 #include <stdio.h>
  28 #include <errno.h>
  29 #include <sys/stat.h>
  30 #include <sys/mman.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #include <ctype.h>
  34 #include <iostream>
  35 #include <apti18n.h>
  36                                                                         /*}}}*/
  37 using namespace std;
  38
  39 // EraseDir - Erase A Directory                                         /*{{{*/
  40 // ---------------------------------------------------------------------
  41 /* This is necessary to create a new empty sub directory. The caller should
  42    invoke mkdir after this with the proper permissions and check for
  43    error. Maybe stick this in fileutils */
  44 static bool EraseDir(const char *Dir)
  45 {
  46    // First we try a simple RM
  47    if (rmdir(Dir) == 0 ||
  48        errno == ENOENT)
  49       return true;
  50
  51    // A file? Easy enough..
  52    if (errno == ENOTDIR)
  53    {
  54       if (unlink(Dir) != 0)
  55          return _error->Errno("unlink",_("Failed to remove %s"),Dir);
  56       return true;
  57    }
  58
  59    // Should not happen
  60    if (errno != ENOTEMPTY)
  61       return _error->Errno("rmdir",_("Failed to remove %s"),Dir);
  62
  63    // Purge it using rm
  64    pid_t Pid = ExecFork();
  65
  66    // Spawn the subprocess
  67    if (Pid == 0)
  68    {
  69       execlp(_config->Find("Dir::Bin::rm","/bin/rm").c_str(),
  70              "rm","-rf","--",Dir,(char *)NULL);
  71       _exit(100);
  72    }
  73    return ExecWait(Pid,_config->Find("dir::bin::rm","/bin/rm").c_str());
  74 }
  75                                                                         /*}}}*/
  76 // DpkgDB::debDpkgDB - Constructor                                      /*{{{*/
  77 // ---------------------------------------------------------------------
  78 /* */
  79 debDpkgDB::debDpkgDB() : CacheMap(0), FileMap(0)
  80 {
  81    AdminDir = flNotFile(_config->Find("Dir::State::status"));
  82    DiverInode = 0;
  83    DiverTime = 0;
  84 }
  85                                                                         /*}}}*/
  86 // DpkgDB::~debDpkgDB - Destructor                                      /*{{{*/
  87 // ---------------------------------------------------------------------
  88 /* */
  89 debDpkgDB::~debDpkgDB()
  90 {
  91    delete Cache;
  92    Cache = 0;
  93    delete CacheMap;
  94    CacheMap = 0;
  95
  96    delete FList;
  97    FList = 0;
  98    delete FileMap;
  99    FileMap = 0;
 100 }
 101                                                                         /*}}}*/
 102 // DpkgDB::InitMetaTmp - Get the temp dir for meta information          /*{{{*/
 103 // ---------------------------------------------------------------------
 104 /* This creats+empties the meta temporary directory /var/lib/dpkg/tmp.ci
 105    Only one package at a time can be using the returned meta directory. */
 106 bool debDpkgDB::InitMetaTmp(string &Dir)
 107 {
 108    string Tmp = AdminDir + "tmp.ci/";
 109    if (EraseDir(Tmp.c_str()) == false)
 110       return _error->Error(_("Unable to create %s"),Tmp.c_str());
 111    if (mkdir(Tmp.c_str(),0755) != 0)
 112       return _error->Errno("mkdir",_("Unable to create %s"),Tmp.c_str());
 113
 114    // Verify it is on the same filesystem as the main info directory
 115    dev_t Dev;
 116    struct stat St;
 117    if (stat((AdminDir + "info").c_str(),&St) != 0)
 118       return _error->Errno("stat",_("Failed to stat %sinfo"),AdminDir.c_str());
 119    Dev = St.st_dev;
 120    if (stat(Tmp.c_str(),&St) != 0)
 121       return _error->Errno("stat",_("Failed to stat %s"),Tmp.c_str());
 122    if (Dev != St.st_dev)
 123       return _error->Error(_("The info and temp directories need to be on the same filesystem"));
 124
 125    // Done
 126    Dir = Tmp;
 127    return true;
 128 }
 129                                                                         /*}}}*/
 130 // DpkgDB::ReadyPkgCache - Prepare the cache with the current status    /*{{{*/
 131 // ---------------------------------------------------------------------
 132 /* This reads in the status file into an empty cache. This really needs
 133    to be somehow unified with the high level APT notion of the Database
 134    directory, but there is no clear way on how to do that yet. */
 135 bool debDpkgDB::ReadyPkgCache(OpProgress &Progress)
 136 {
 137    if (Cache != 0)
 138    {
 139       Progress.OverallProgress(1,1,1,_("Reading package lists"));
 140       return true;
 141    }
 142
 143    if (CacheMap != 0)
 144    {
 145       delete CacheMap;
 146       CacheMap = 0;
 147    }
 148
 149    if (pkgMakeOnlyStatusCache(Progress,&CacheMap) == false)
 150       return false;
 151    Cache->DropProgress();
 152
 153    return true;
 154 }
 155                                                                         /*}}}*/
 156 // DpkgDB::ReadFList - Read the File Listings in                        /*{{{*/
 157 // ---------------------------------------------------------------------
 158 /* This reads the file listing in from the state directory. This is a
 159    performance critical routine, as it needs to parse about 50k lines of
 160    text spread over a hundred or more files. For an initial cold start
 161    most of the time is spent in reading file inodes and so on, not
 162    actually parsing. */
 163 bool debDpkgDB::ReadFList(OpProgress &Progress)
 164 {
 165    // Count the number of packages we need to read information for
 166    unsigned long Total = 0;
 167    pkgCache &Cache = this->Cache->GetCache();
 168    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 169    {
 170       // Only not installed packages have no files.
 171       if (I->CurrentState == pkgCache::State::NotInstalled)
 172          continue;
 173       Total++;
 174    }
 175
 176    /* Switch into the admin dir, this prevents useless lookups for the
 177       path components */
 178    string Cwd = SafeGetCWD();
 179    if (chdir((AdminDir + "info/").c_str()) != 0)
 180       return _error->Errno("chdir",_("Failed to change to the admin dir %sinfo"),AdminDir.c_str());
 181
 182    // Allocate a buffer. Anything larger than this buffer will be mmaped
 183    unsigned long BufSize = 32*1024;
 184    char *Buffer = new char[BufSize];
 185
 186    // Begin Loading them
 187    unsigned long Count = 0;
 188    char Name[300];
 189    for (pkgCache::PkgIterator I = Cache.PkgBegin(); I.end() == false; I++)
 190    {
 191       /* Only not installed packages have no files. ConfFile packages have
 192          file lists but we don't want to read them in */
 193       if (I->CurrentState == pkgCache::State::NotInstalled ||
 194           I->CurrentState == pkgCache::State::ConfigFiles)
 195          continue;
 196
 197       // Fetch a package handle to associate with the file
 198       pkgFLCache::PkgIterator FlPkg = FList->GetPkg(I.Name(),0,true);
 199       if (FlPkg.end() == true)
 200       {
 201          _error->Error(_("Internal error getting a package name"));
 202          break;
 203       }
 204
 205       Progress.OverallProgress(Count,Total,1,_("Reading file listing"));
 206
 207       // Open the list file
 208       snprintf(Name,sizeof(Name),"%s.list",I.Name());
 209       int Fd = open(Name,O_RDONLY);
 210
 211       /* Okay this is very strange and bad.. Best thing is to bail and
 212          instruct the user to look into it. */
 213       struct stat Stat;
 214       if (Fd == -1 || fstat(Fd,&Stat) != 0)
 215       {
 216          _error->Errno("open",_("Failed to open the list file '%sinfo/%s'. If you "
 217                        "cannot restore this file then make it empty "
 218                        "and immediately re-install the same version of the package!"),
 219                        AdminDir.c_str(),Name);
 220          break;
 221       }
 222
 223       // Set File to be a memory buffer containing the whole file
 224       char *File;
 225       if ((unsigned)Stat.st_size < BufSize)
 226       {
 227          if (read(Fd,Buffer,Stat.st_size) != Stat.st_size)
 228          {
 229             _error->Errno("read",_("Failed reading the list file %sinfo/%s"),
 230                           AdminDir.c_str(),Name);
 231             close(Fd);
 232             break;
 233          }
 234          File = Buffer;
 235       }
 236       else
 237       {
 238          // Use mmap
 239          File = (char *)mmap(0,Stat.st_size,PROT_READ,MAP_PRIVATE,Fd,0);
 240          if (File == (char *)(-1))
 241          {
 242             _error->Errno("mmap",_("Failed reading the list file %sinfo/%s"),
 243                           AdminDir.c_str(),Name);
 244             close(Fd);
 245             break;
 246          }
 247       }
 248
 249       // Parse it
 250       const char *Start = File;
 251       const char *End = File;
 252       const char *Finish = File + Stat.st_size;
 253       for (; End < Finish; End++)
 254       {
 255          // Not an end of line
 256          if (*End != '\n' && End + 1 < Finish)
 257             continue;
 258
 259          // Skip blank lines
 260          if (End - Start > 1)
 261          {
 262             pkgFLCache::NodeIterator Node = FList->GetNode(Start,End,
 263                                               FlPkg.Offset(),true,false);
 264             if (Node.end() == true)
 265             {
 266                _error->Error(_("Internal error getting a node"));
 267                break;
 268             }
 269          }
 270
 271          // Skip past the end of line
 272          for (; *End == '\n' && End < Finish; End++);
 273          Start = End;
 274       }
 275
 276       close(Fd);
 277       if ((unsigned)Stat.st_size >= BufSize)
 278          munmap((caddr_t)File,Stat.st_size);
 279
 280       // Failed
 281       if (End < Finish)
 282          break;
 283
 284       Count++;
 285    }
 286
 287    delete [] Buffer;
 288    if (chdir(Cwd.c_str()) != 0)
 289       chdir("/");
 290
 291    return !_error->PendingError();
 292 }
 293                                                                         /*}}}*/
 294 // DpkgDB::ReadDiversions - Load the diversions file                    /*{{{*/
 295 // ---------------------------------------------------------------------
 296 /* Read the diversion file in from disk. This is usually invoked by
 297    LoadChanges before performing an operation that uses the FLCache. */
 298 bool debDpkgDB::ReadDiversions()
 299 {
 300    struct stat Stat;
 301    if (stat((AdminDir + "diversions").c_str(),&Stat) != 0)
 302       return true;
 303
 304    if (_error->PendingError() == true)
 305       return false;
 306
 307    FILE *Fd = fopen((AdminDir + "diversions").c_str(),"r");
 308    if (Fd == 0)
 309       return _error->Errno("fopen",_("Failed to open the diversions file %sdiversions"),AdminDir.c_str());
 310
 311    FList->BeginDiverLoad();
 312    while (1)
 313    {
 314       char From[300];
 315       char To[300];
 316       char Package[100];
 317
 318       // Read the three lines in
 319       if (fgets(From,sizeof(From),Fd) == 0)
 320          break;
 321       if (fgets(To,sizeof(To),Fd) == 0 ||
 322           fgets(Package,sizeof(Package),Fd) == 0)
 323       {
 324          _error->Error(_("The diversion file is corrupted"));
 325          break;
 326       }
 327
 328       // Strip the \ns
 329       unsigned long Len = strlen(From);
 330       if (Len < 2 || From[Len-1] != '\n')
 331          _error->Error(_("Invalid line in the diversion file: %s"),From);
 332       else
 333          From[Len-1] = 0;
 334       Len = strlen(To);
 335       if (Len < 2 || To[Len-1] != '\n')
 336          _error->Error(_("Invalid line in the diversion file: %s"),To);
 337       else
 338          To[Len-1] = 0;
 339       Len = strlen(Package);
 340       if (Len < 2 || Package[Len-1] != '\n')
 341          _error->Error(_("Invalid line in the diversion file: %s"),Package);
 342       else
 343          Package[Len-1] = 0;
 344
 345       // Make sure the lines were parsed OK
 346       if (_error->PendingError() == true)
 347          break;
 348
 349       // Fetch a package
 350       if (strcmp(Package,":") == 0)
 351          Package[0] = 0;
 352       pkgFLCache::PkgIterator FlPkg = FList->GetPkg(Package,0,true);
 353       if (FlPkg.end() == true)
 354       {
 355          _error->Error(_("Internal error getting a package name"));
 356          break;
 357       }
 358
 359       // Install the diversion
 360       if (FList->AddDiversion(FlPkg,From,To) == false)
 361       {
 362          _error->Error(_("Internal error adding a diversion"));
 363          break;
 364       }
 365    }
 366    if (_error->PendingError() == false)
 367       FList->FinishDiverLoad();
 368
 369    DiverInode = Stat.st_ino;
 370    DiverTime = Stat.st_mtime;
 371
 372    fclose(Fd);
 373    return !_error->PendingError();
 374 }
 375                                                                         /*}}}*/
 376 // DpkgDB::ReadFileList - Read the file listing                         /*{{{*/
 377 // ---------------------------------------------------------------------
 378 /* Read in the file listing. The file listing is created from three
 379    sources, *.list, Conffile sections and the Diversion table. */
 380 bool debDpkgDB::ReadyFileList(OpProgress &Progress)
 381 {
 382    if (Cache == 0)
 383       return _error->Error(_("The pkg cache must be initialized first"));
 384    if (FList != 0)
 385    {
 386       Progress.OverallProgress(1,1,1,_("Reading file listing"));
 387       return true;
 388    }
 389
 390    // Create the cache and read in the file listing
 391    FileMap = new DynamicMMap(MMap::Public);
 392    FList = new pkgFLCache(*FileMap);
 393    if (_error->PendingError() == true ||
 394        ReadFList(Progress) == false ||
 395        ReadConfFiles() == false ||
 396        ReadDiversions() == false)
 397    {
 398       delete FList;
 399       delete FileMap;
 400       FileMap = 0;
 401       FList = 0;
 402       return false;
 403    }
 404
 405    cout << "Node: " << FList->HeaderP->NodeCount << ',' << FList->HeaderP->UniqNodes << endl;
 406    cout << "Dir: " << FList->HeaderP->DirCount << endl;
 407    cout << "Package: " << FList->HeaderP->PackageCount << endl;
 408    cout << "HashSize: " << FList->HeaderP->HashSize << endl;
 409    cout << "Size: " << FileMap->Size() << endl;
 410    cout << endl;
 411
 412    return true;
 413 }
 414                                                                         /*}}}*/
 415 // DpkgDB::ReadConfFiles - Read the conf file sections from the s-file  /*{{{*/
 416 // ---------------------------------------------------------------------
 417 /* Reading the conf files is done by reparsing the status file. This is
 418    actually rather fast so it is no big deal. */
 419 bool debDpkgDB::ReadConfFiles()
 420 {
 421    FileFd File(_config->FindFile("Dir::State::status"),FileFd::ReadOnly);
 422    pkgTagFile Tags(&File);
 423    if (_error->PendingError() == true)
 424       return false;
 425
 426    pkgTagSection Section;
 427    while (1)
 428    {
 429       // Skip to the next section
 430       unsigned long Offset = Tags.Offset();
 431       if (Tags.Step(Section) == false)
 432          break;
 433
 434       // Parse the line
 435       const char *Start;
 436       const char *Stop;
 437       if (Section.Find("Conffiles",Start,Stop) == false)
 438          continue;
 439
 440       const char *PkgStart;
 441       const char *PkgEnd;
 442       if (Section.Find("Package",PkgStart,PkgEnd) == false)
 443          return _error->Error(_("Failed to find a Package: header, offset %lu"),Offset);
 444
 445       // Snag a package record for it
 446       pkgFLCache::PkgIterator FlPkg = FList->GetPkg(PkgStart,PkgEnd,true);
 447       if (FlPkg.end() == true)
 448          return _error->Error(_("Internal error getting a package name"));
 449
 450       // Parse the conf file lines
 451       while (1)
 452       {
 453          for (; isspace(*Start) != 0 && Start < Stop; Start++);
 454          if (Start == Stop)
 455             break;
 456
 457          // Split it into words
 458          const char *End = Start;
 459          for (; isspace(*End) == 0 && End < Stop; End++);
 460          const char *StartMd5 = End;
 461          for (; isspace(*StartMd5) != 0 && StartMd5 < Stop; StartMd5++);
 462          const char *EndMd5 = StartMd5;
 463          for (; isspace(*EndMd5) == 0 && EndMd5 < Stop; EndMd5++);
 464          if (StartMd5 == EndMd5 || Start == End)
 465             return _error->Error(_("Bad ConfFile section in the status file. Offset %lu"),Offset);
 466
 467          // Insert a new entry
 468          unsigned char MD5[16];
 469          if (Hex2Num(string(StartMd5,EndMd5-StartMd5),MD5,16) == false)
 470             return _error->Error(_("Error parsing MD5. Offset %lu"),Offset);
 471
 472          if (FList->AddConfFile(Start,End,FlPkg,MD5) == false)
 473             return false;
 474          Start = EndMd5;
 475       }
 476    }
 477
 478    return true;
 479 }
 480                                                                         /*}}}*/
 481 // DpkgDB::LoadChanges - Read in any changed state files                /*{{{*/
 482 // ---------------------------------------------------------------------
 483 /* The only file in the dpkg system that can change while packages are
 484    unpacking is the diversions file. */
 485 bool debDpkgDB::LoadChanges()
 486 {
 487    struct stat Stat;
 488    if (stat((AdminDir + "diversions").c_str(),&Stat) != 0)
 489       return true;
 490    if (DiverInode == Stat.st_ino && DiverTime == Stat.st_mtime)
 491       return true;
 492    return ReadDiversions();
 493 }
 494                                                                         /*}}}*/