apt-pkg/pkgcachegen.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: pkgcachegen.cc,v 1.15 1998/09/07 05:28:37 jgg Exp $
   4 /* ######################################################################
   5
   6    Package Cache Generator - Generator for the cache structure.
   7
   8    This builds the cache structure from the abstract package list parser.
   9
  10    ##################################################################### */
  11                                                                         /*}}}*/
  12 // Include Files                                                        /*{{{*/
  13 #ifdef __GNUG__
  14 #pragma implementation "apt-pkg/pkgcachegen.h"
  15 #endif
  16
  17 #include <apt-pkg/pkgcachegen.h>
  18 #include <apt-pkg/error.h>
  19 #include <apt-pkg/version.h>
  20 #include <apt-pkg/progress.h>
  21 #include <apt-pkg/sourcelist.h>
  22 #include <apt-pkg/configuration.h>
  23 #include <apt-pkg/deblistparser.h>
  24
  25 #include <strutl.h>
  26
  27 #include <sys/stat.h>
  28 #include <unistd.h>
  29                                                                         /*}}}*/
  30
  31 // CacheGenerator::pkgCacheGenerator - Constructor                      /*{{{*/
  32 // ---------------------------------------------------------------------
  33 /* We set the diry flag and make sure that is written to the disk */
  34 pkgCacheGenerator::pkgCacheGenerator(DynamicMMap &Map,OpProgress &Prog) :
  35                     Map(Map), Cache(Map), Progress(Prog)
  36 {
  37    if (_error->PendingError() == true)
  38       return;
  39
  40    if (Map.Size() == 0)
  41    {
  42       Map.RawAllocate(sizeof(pkgCache::Header));
  43       *Cache.HeaderP = pkgCache::Header();
  44    }
  45    Cache.HeaderP->Dirty = true;
  46    Map.Sync(0,sizeof(pkgCache::Header));
  47    Map.UsePools(*Cache.HeaderP->Pools,sizeof(Cache.HeaderP->Pools)/sizeof(Cache.HeaderP->Pools[0]));
  48 }
  49                                                                         /*}}}*/
  50 // CacheGenerator::~pkgCacheGenerator - Destructor                      /*{{{*/
  51 // ---------------------------------------------------------------------
  52 /* We sync the data then unset the dirty flag in two steps so as to
  53    advoid a problem during a crash */
  54 pkgCacheGenerator::~pkgCacheGenerator()
  55 {
  56    if (_error->PendingError() == true)
  57       return;
  58    if (Map.Sync() == false)
  59       return;
  60
  61    Cache.HeaderP->Dirty = false;
  62    Map.Sync(0,sizeof(pkgCache::Header));
  63 }
  64                                                                         /*}}}*/
  65 // CacheGenerator::MergeList - Merge the package list                   /*{{{*/
  66 // ---------------------------------------------------------------------
  67 /* This provides the generation of the entries in the cache. Each loop
  68    goes through a single package record from the underlying parse engine. */
  69 bool pkgCacheGenerator::MergeList(ListParser &List)
  70 {
  71    List.Owner = this;
  72
  73    int Counter = 0;
  74    while (List.Step() == true)
  75    {
  76       // Get a pointer to the package structure
  77       string PackageName = List.Package();
  78       pkgCache::PkgIterator Pkg;
  79       if (NewPackage(Pkg,PackageName) == false)
  80          return _error->Error("Error occured while processing %s (NewPackage)",PackageName.c_str());
  81       Counter++;
  82       if (Counter % 100 == 0)
  83          Progress.Progress(List.Offset());
  84
  85       /* Get a pointer to the version structure. We know the list is sorted
  86          so we use that fact in the search. Insertion of new versions is
  87          done with correct sorting */
  88       string Version = List.Version();
  89       if (Version.empty() == true)
  90       {
  91          if (List.UsePackage(Pkg,pkgCache::VerIterator(Cache)) == false)
  92             return _error->Error("Error occured while processing %s (UsePackage1)",PackageName.c_str());
  93          continue;
  94       }
  95
  96       pkgCache::VerIterator Ver = Pkg.VersionList();
  97       unsigned long *Last = &Pkg->VersionList;
  98       int Res = 1;
  99       for (; Ver.end() == false; Last = &Ver->NextVer, Ver++)
 100       {
 101          Res = pkgVersionCompare(Version.begin(),Version.end(),Ver.VerStr(),
 102                                  Ver.VerStr() + strlen(Ver.VerStr()));
 103          if (Res >= 0)
 104             break;
 105       }
 106
 107       /* We already have a version for this item, record that we
 108          saw it */
 109       if (Res == 0)
 110       {
 111          if (List.UsePackage(Pkg,Ver) == false)
 112             return _error->Error("Error occured while processing %s (UsePackage2)",PackageName.c_str());
 113
 114          if (NewFileVer(Ver,List) == false)
 115             return _error->Error("Error occured while processing %s (NewFileVer1)",PackageName.c_str());
 116
 117          continue;
 118       }
 119
 120       // Add a new version
 121       *Last = NewVersion(Ver,Version,*Last);
 122       Ver->ParentPkg = Pkg.Index();
 123       if (List.NewVersion(Ver) == false)
 124          return _error->Error("Error occured while processing %s (NewVersion1)",PackageName.c_str());
 125
 126       if (List.UsePackage(Pkg,Ver) == false)
 127          return _error->Error("Error occured while processing %s (UsePackage3)",PackageName.c_str());
 128
 129       if (NewFileVer(Ver,List) == false)
 130          return _error->Error("Error occured while processing %s (NewVersion2)",PackageName.c_str());
 131    }
 132
 133    return true;
 134 }
 135                                                                         /*}}}*/
 136 // CacheGenerator::NewPackage - Add a new package                       /*{{{*/
 137 // ---------------------------------------------------------------------
 138 /* This creates a new package structure and adds it to the hash table */
 139 bool pkgCacheGenerator::NewPackage(pkgCache::PkgIterator &Pkg,string Name)
 140 {
 141    Pkg = Cache.FindPkg(Name);
 142    if (Pkg.end() == false)
 143       return true;
 144
 145    // Get a structure
 146    unsigned long Package = Map.Allocate(sizeof(pkgCache::Package));
 147    if (Package == 0)
 148       return false;
 149
 150    Pkg = pkgCache::PkgIterator(Cache,Cache.PkgP + Package);
 151
 152    // Insert it into the hash table
 153    unsigned long Hash = Cache.Hash(Name);
 154    Pkg->NextPackage = Cache.HeaderP->HashTable[Hash];
 155    Cache.HeaderP->HashTable[Hash] = Package;
 156
 157    // Set the name and the ID
 158    Pkg->Name = Map.WriteString(Name);
 159    if (Pkg->Name == 0)
 160       return false;
 161    Pkg->ID = Cache.HeaderP->PackageCount++;
 162
 163    return true;
 164 }
 165                                                                         /*}}}*/
 166 // CacheGenerator::NewFileVer - Create a new File<->Version association /*{{{*/
 167 // ---------------------------------------------------------------------
 168 /* */
 169 bool pkgCacheGenerator::NewFileVer(pkgCache::VerIterator &Ver,
 170                                    ListParser &List)
 171 {
 172    // Get a structure
 173    unsigned long VerFile = Map.Allocate(sizeof(pkgCache::VerFile));
 174    if (VerFile == 0)
 175       return 0;
 176
 177    pkgCache::VerFileIterator VF(Cache,Cache.VerFileP + VerFile);
 178    VF->File = CurrentFile - Cache.PkgFileP;
 179    VF->NextFile = Ver->FileList;
 180    Ver->FileList = VF.Index();
 181    VF->Offset = List.Offset();
 182    VF->Size = List.Size();
 183    if (Cache.HeaderP->MaxVerFileSize < VF->Size)
 184       Cache.HeaderP->MaxVerFileSize = VF->Size;
 185    return true;
 186 }
 187                                                                         /*}}}*/
 188 // CacheGenerator::NewVersion - Create a new Version                    /*{{{*/
 189 // ---------------------------------------------------------------------
 190 /* This puts a version structure in the linked list */
 191 unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver,
 192                                             string VerStr,
 193                                             unsigned long Next)
 194 {
 195    // Get a structure
 196    unsigned long Version = Map.Allocate(sizeof(pkgCache::Version));
 197    if (Version == 0)
 198       return 0;
 199
 200    // Fill it in
 201    Ver = pkgCache::VerIterator(Cache,Cache.VerP + Version);
 202    Ver->NextVer = Next;
 203    Ver->ID = Cache.HeaderP->VersionCount++;
 204    Ver->VerStr = Map.WriteString(VerStr);
 205    if (Ver->VerStr == 0)
 206       return 0;
 207
 208    return Version;
 209 }
 210                                                                         /*}}}*/
 211 // ListParser::NewDepends - Create a dependency element                 /*{{{*/
 212 // ---------------------------------------------------------------------
 213 /* This creates a dependency element in the tree. It is linked to the
 214    version and to the package that it is pointing to. */
 215 bool pkgCacheGenerator::ListParser::NewDepends(pkgCache::VerIterator Ver,
 216                                                string PackageName,
 217                                                string Version,
 218                                                unsigned int Op,
 219                                                unsigned int Type)
 220 {
 221    pkgCache &Cache = Owner->Cache;
 222
 223    // Get a structure
 224    unsigned long Dependency = Owner->Map.Allocate(sizeof(pkgCache::Dependency));
 225    if (Dependency == 0)
 226       return false;
 227
 228    // Fill it in
 229    pkgCache::DepIterator Dep(Cache,Cache.DepP + Dependency);
 230    Dep->ParentVer = Ver.Index();
 231    Dep->Type = Type;
 232    Dep->CompareOp = Op;
 233    Dep->ID = Cache.HeaderP->DependsCount++;
 234
 235    // Locate the target package
 236    pkgCache::PkgIterator Pkg;
 237    if (Owner->NewPackage(Pkg,PackageName) == false)
 238       return false;
 239
 240    // Probe the reverse dependency list for a version string that matches
 241    if (Version.empty() == false)
 242    {
 243       for (pkgCache::DepIterator I = Pkg.RevDependsList(); I.end() == false; I++)
 244          if (I->Version != 0 && I.TargetVer() == Version)
 245             Dep->Version = I->Version;
 246       if (Dep->Version == 0)
 247          if ((Dep->Version = WriteString(Version)) == 0)
 248             return false;
 249    }
 250
 251    // Link it to the package
 252    Dep->Package = Pkg.Index();
 253    Dep->NextRevDepends = Pkg->RevDepends;
 254    Pkg->RevDepends = Dep.Index();
 255
 256    // Link it to the version (at the end of the list)
 257    unsigned long *Last = &Ver->DependsList;
 258    for (pkgCache::DepIterator D = Ver.DependsList(); D.end() == false; D++)
 259       Last = &D->NextDepends;
 260    Dep->NextDepends = *Last;
 261    *Last = Dep.Index();
 262
 263    return true;
 264 }
 265                                                                         /*}}}*/
 266 // ListParser::NewProvides - Create a Provides element                  /*{{{*/
 267 // ---------------------------------------------------------------------
 268 /* */
 269 bool pkgCacheGenerator::ListParser::NewProvides(pkgCache::VerIterator Ver,
 270                                                 string PackageName,
 271                                                 string Version)
 272 {
 273    pkgCache &Cache = Owner->Cache;
 274
 275    // We do not add self referencing provides
 276    if (Ver.ParentPkg().Name() == PackageName)
 277       return true;
 278
 279    // Get a structure
 280    unsigned long Provides = Owner->Map.Allocate(sizeof(pkgCache::Provides));
 281    if (Provides == 0)
 282       return false;
 283
 284    // Fill it in
 285    pkgCache::PrvIterator Prv(Cache,Cache.ProvideP + Provides,Cache.PkgP);
 286    Prv->Version = Ver.Index();
 287    Prv->NextPkgProv = Ver->ProvidesList;
 288    Ver->ProvidesList = Prv.Index();
 289    if (Version.empty() == false && (Prv->Version = WriteString(Version)) == 0)
 290       return false;
 291
 292    // Locate the target package
 293    pkgCache::PkgIterator Pkg;
 294    if (Owner->NewPackage(Pkg,PackageName) == false)
 295       return false;
 296
 297    // Link it to the package
 298    Prv->ParentPkg = Pkg.Index();
 299    Prv->NextProvides = Pkg->ProvidesList;
 300    Pkg->ProvidesList = Prv.Index();
 301
 302    return true;
 303 }
 304                                                                         /*}}}*/
 305 // CacheGenerator::SelectFile - Select the current file being parsed    /*{{{*/
 306 // ---------------------------------------------------------------------
 307 /* This is used to select which file is to be associated with all newly
 308    added versions. */
 309 bool pkgCacheGenerator::SelectFile(string File,unsigned long Flags)
 310 {
 311    struct stat Buf;
 312    if (stat(File.c_str(),&Buf) == -1)
 313       return _error->Errno("stat","Couldn't stat ",File.c_str());
 314
 315    // Get some space for the structure
 316    CurrentFile = Cache.PkgFileP + Map.Allocate(sizeof(*CurrentFile));
 317    if (CurrentFile == Cache.PkgFileP)
 318       return false;
 319
 320    // Fill it in
 321    CurrentFile->FileName = Map.WriteString(File);
 322    CurrentFile->Size = Buf.st_size;
 323    CurrentFile->mtime = Buf.st_mtime;
 324    CurrentFile->NextFile = Cache.HeaderP->FileList;
 325    CurrentFile->Flags = Flags;
 326    PkgFileName = File;
 327    Cache.HeaderP->FileList = CurrentFile - Cache.PkgFileP;
 328    Cache.HeaderP->PackageFileCount++;
 329
 330    if (CurrentFile->FileName == 0)
 331       return false;
 332
 333    Progress.SubProgress(Buf.st_size);
 334    return true;
 335 }
 336                                                                         /*}}}*/
 337 // CacheGenerator::WriteUniqueString - Insert a unique string           /*{{{*/
 338 // ---------------------------------------------------------------------
 339 /* This is used to create handles to strings. Given the same text it
 340    always returns the same number */
 341 unsigned long pkgCacheGenerator::WriteUniqString(const char *S,
 342                                                  unsigned int Size)
 343 {
 344    // Search for an insertion point
 345    pkgCache::StringItem *I = Cache.StringItemP + Cache.HeaderP->StringList;
 346    int Res = 1;
 347    unsigned long *Last = &Cache.HeaderP->StringList;
 348    for (; I != Cache.StringItemP; Last = &I->NextItem,
 349         I = Cache.StringItemP + I->NextItem)
 350    {
 351       Res = stringcmp(S,S+Size,Cache.StrP + I->String);
 352       if (Res >= 0)
 353          break;
 354    }
 355
 356    // Match
 357    if (Res == 0)
 358       return I->String;
 359
 360    // Get a structure
 361    unsigned long Item = Map.Allocate(sizeof(pkgCache::StringItem));
 362    if (Item == 0)
 363       return 0;
 364
 365    // Fill in the structure
 366    pkgCache::StringItem *ItemP = Cache.StringItemP + Item;
 367    ItemP->NextItem = I - Cache.StringItemP;
 368    *Last = Item;
 369    ItemP->String = Map.WriteString(S,Size);
 370    if (ItemP->String == 0)
 371       return 0;
 372
 373    return ItemP->String;
 374 }
 375                                                                         /*}}}*/
 376
 377 // SrcCacheCheck - Check if the source package cache is uptodate        /*{{{*/
 378 // ---------------------------------------------------------------------
 379 /* The source cache is checked against the source list and the files
 380    on disk, any difference results in a false. */
 381 bool pkgSrcCacheCheck(pkgSourceList &List)
 382 {
 383    if (_error->PendingError() == true)
 384       return false;
 385
 386    // Open the source package cache
 387    string CacheFile = _config->FindDir("Dir::Cache::srcpkgcache");
 388    string ListDir = _config->FindDir("Dir::State::lists");
 389    if (FileExists(CacheFile) == false)
 390       return false;
 391
 392    FileFd CacheF(CacheFile,FileFd::ReadOnly);
 393    if (_error->PendingError() == true)
 394    {
 395       _error->Discard();
 396       return false;
 397    }
 398
 399    MMap Map(CacheF,MMap::Public | MMap::ReadOnly);
 400    if (_error->PendingError() == true)
 401    {
 402       _error->Discard();
 403       return false;
 404    }
 405
 406    pkgCache Cache(Map);
 407    if (_error->PendingError() == true)
 408    {
 409       _error->Discard();
 410       return false;
 411    }
 412
 413    // They are certianly out of sync
 414    if (Cache.Head().PackageFileCount != List.size())
 415       return false;
 416
 417    for (pkgCache::PkgFileIterator F(Cache); F.end() == false; F++)
 418    {
 419       // Search for a match in the source list
 420       bool Bad = true;
 421       for (pkgSourceList::const_iterator I = List.begin();
 422            I != List.end(); I++)
 423       {
 424          string File = ListDir + URItoFileName(I->PackagesURI());
 425          if (F.FileName() == File)
 426          {
 427             Bad = false;
 428             break;
 429          }
 430       }
 431
 432       // Check if the file matches what was cached
 433       Bad |= !F.IsOk();
 434       if (Bad == true)
 435          return false;
 436    }
 437
 438    return true;
 439 }
 440                                                                         /*}}}*/
 441 // PkgCacheCheck - Check if the package cache is uptodate               /*{{{*/
 442 // ---------------------------------------------------------------------
 443 /* This does a simple check of all files used to compose the cache */
 444 bool pkgPkgCacheCheck(string CacheFile)
 445 {
 446    if (_error->PendingError() == true)
 447       return false;
 448
 449    // Open the source package cache
 450    if (FileExists(CacheFile) == false)
 451       return false;
 452
 453    FileFd CacheF(CacheFile,FileFd::ReadOnly);
 454    if (_error->PendingError() == true)
 455    {
 456       _error->Discard();
 457       return false;
 458    }
 459
 460    MMap Map(CacheF,MMap::Public | MMap::ReadOnly);
 461    if (_error->PendingError() == true)
 462    {
 463       _error->Discard();
 464       return false;
 465    }
 466
 467    pkgCache Cache(Map);
 468    if (_error->PendingError() == true)
 469    {
 470       _error->Discard();
 471       return false;
 472    }
 473
 474    // Cheack each file
 475    for (pkgCache::PkgFileIterator F(Cache); F.end() == false; F++)
 476       if (F.IsOk() == false)
 477          return false;
 478    return true;
 479 }
 480                                                                         /*}}}*/
 481 // AddSourcesSize - Add the size of the status files                    /*{{{*/
 482 // ---------------------------------------------------------------------
 483 /* This adds the size of all the status files to the size counter */
 484 static bool pkgAddSourcesSize(unsigned long &TotalSize)
 485 {
 486    // Grab the file names
 487    string xstatus = _config->FindDir("Dir::State::xstatus");
 488    string userstatus = _config->FindDir("Dir::State::userstatus");
 489    string status = _config->FindDir("Dir::State::status");
 490
 491    // Grab the sizes
 492    struct stat Buf;
 493    if (stat(xstatus.c_str(),&Buf) == 0)
 494       TotalSize += Buf.st_size;
 495    if (stat(userstatus.c_str(),&Buf) == 0)
 496       TotalSize += Buf.st_size;
 497    if (stat(status.c_str(),&Buf) != 0)
 498       return _error->Errno("stat","Couldn't stat the status file %s",status.c_str());
 499    TotalSize += Buf.st_size;
 500
 501    return true;
 502 }
 503                                                                         /*}}}*/
 504 // MergeStatus - Add the status files to the cache                      /*{{{*/
 505 // ---------------------------------------------------------------------
 506 /* This adds the status files to the map */
 507 static bool pkgMergeStatus(OpProgress &Progress,pkgCacheGenerator &Gen,
 508                            unsigned long &CurrentSize,unsigned long TotalSize)
 509 {
 510    // Grab the file names
 511    string Status[3];
 512    Status[0] = _config->FindDir("Dir::State::xstatus");
 513    Status[1]= _config->FindDir("Dir::State::userstatus");
 514    Status[2] = _config->FindDir("Dir::State::status");
 515
 516    for (int I = 0; I != 3; I++)
 517    {
 518       // Check if the file exists and it is not the primary status file.
 519       string File = Status[I];
 520       if (I != 2 && FileExists(File) == false)
 521          continue;
 522
 523       FileFd Pkg(File,FileFd::ReadOnly);
 524       debListParser Parser(Pkg);
 525       Progress.OverallProgress(CurrentSize,TotalSize,Pkg.Size(),"Reading Package Lists");
 526       if (_error->PendingError() == true)
 527          return _error->Error("Problem opening %s",File.c_str());
 528       CurrentSize += Pkg.Size();
 529
 530       Progress.SubProgress(0,"Local Package State - " + flNotDir(File));
 531       if (Gen.SelectFile(File,pkgCache::Flag::NotSource) == false)
 532          return _error->Error("Problem with SelectFile %s",File.c_str());
 533
 534       if (Gen.MergeList(Parser) == false)
 535          return _error->Error("Problem with MergeList %s",File.c_str());
 536       Progress.Progress(Pkg.Size());
 537    }
 538
 539    return true;
 540 }
 541                                                                         /*}}}*/
 542 // MakeStatusCache - Generates a cache that includes the status files   /*{{{*/
 543 // ---------------------------------------------------------------------
 544 /* This copies the package source cache and then merges the status and
 545    xstatus files into it. */
 546 bool pkgMakeStatusCache(pkgSourceList &List,OpProgress &Progress)
 547 {
 548    Progress.OverallProgress(0,1,1,"Reading Package Lists");
 549
 550    string CacheFile = _config->FindDir("Dir::Cache::pkgcache");
 551    bool SrcOk = pkgSrcCacheCheck(List);
 552    bool PkgOk = pkgPkgCacheCheck(CacheFile);
 553
 554    // Rebuild the source and package caches
 555    if (SrcOk == false)
 556    {
 557       string SCacheFile = _config->FindDir("Dir::Cache::srcpkgcache");
 558       string ListDir = _config->FindDir("Dir::State::lists");
 559
 560       FileFd SCacheF(SCacheFile,FileFd::WriteEmpty);
 561       FileFd CacheF(CacheFile,FileFd::WriteEmpty);
 562       DynamicMMap Map(CacheF,MMap::Public);
 563       if (_error->PendingError() == true)
 564          return false;
 565
 566       pkgCacheGenerator Gen(Map,Progress);
 567
 568       // Prepare the progress indicator
 569       unsigned long TotalSize = 0;
 570       struct stat Buf;
 571       for (pkgSourceList::const_iterator I = List.begin(); I != List.end(); I++)
 572       {
 573          string File = ListDir + URItoFileName(I->PackagesURI());
 574          if (stat(File.c_str(),&Buf) != 0)
 575             return _error->Errno("stat","Couldn't stat source package list %s",File.c_str());
 576          TotalSize += Buf.st_size;
 577       }
 578
 579       if (pkgAddSourcesSize(TotalSize) == false)
 580          return false;
 581
 582       // Generate the pkg source cache
 583       unsigned long CurrentSize = 0;
 584       for (pkgSourceList::const_iterator I = List.begin(); I != List.end(); I++)
 585       {
 586          string File = ListDir + URItoFileName(I->PackagesURI());
 587          FileFd Pkg(File,FileFd::ReadOnly);
 588          debListParser Parser(Pkg);
 589          Progress.OverallProgress(CurrentSize,TotalSize,Pkg.Size(),"Reading Package Lists");
 590          if (_error->PendingError() == true)
 591             return _error->Error("Problem opening %s",File.c_str());
 592          CurrentSize += Pkg.Size();
 593
 594          Progress.SubProgress(0,I->PackagesInfo());
 595          if (Gen.SelectFile(File) == false)
 596             return _error->Error("Problem with SelectFile %s",File.c_str());
 597
 598          if (Gen.MergeList(Parser) == false)
 599             return _error->Error("Problem with MergeList %s",File.c_str());
 600       }
 601
 602       // Write the src cache
 603       Gen.GetCache().HeaderP->Dirty = false;
 604       if (SCacheF.Write(Map.Data(),Map.Size()) == false)
 605          return _error->Error("IO Error saving source cache");
 606       Gen.GetCache().HeaderP->Dirty = true;
 607
 608       // Merge in the source caches
 609       return pkgMergeStatus(Progress,Gen,CurrentSize,TotalSize);
 610    }
 611
 612    if (PkgOk == true)
 613    {
 614       Progress.OverallProgress(1,1,1,"Reading Package Lists");
 615       return true;
 616    }
 617
 618    // We use the source cache to generate the package cache
 619    string SCacheFile = _config->FindDir("Dir::Cache::srcpkgcache");
 620
 621    FileFd SCacheF(SCacheFile,FileFd::ReadOnly);
 622    FileFd CacheF(CacheFile,FileFd::WriteEmpty);
 623    DynamicMMap Map(CacheF,MMap::Public);
 624    if (_error->PendingError() == true)
 625       return false;
 626
 627    // Preload the map with the source cache
 628    if (SCacheF.Read((unsigned char *)Map.Data() + Map.RawAllocate(SCacheF.Size()),
 629                     SCacheF.Size()) == false)
 630       return false;
 631
 632    pkgCacheGenerator Gen(Map,Progress);
 633
 634    // Compute the progress
 635    unsigned long TotalSize = 0;
 636    if (pkgAddSourcesSize(TotalSize) == false)
 637       return false;
 638
 639    unsigned long CurrentSize = 0;
 640    return pkgMergeStatus(Progress,Gen,CurrentSize,TotalSize);
 641 }
 642                                                                         /*}}}*/