apt-pkg/pkgcachegen.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: pkgcachegen.cc,v 1.4 1998/07/05 05:33:56 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 #include <pkglib/pkgcachegen.h>
  14 #include <pkglib/error.h>
  15 #include <pkglib/version.h>
  16
  17 #include <sys/stat.h>
  18 #include <unistd.h>
  19                                                                         /*}}}*/
  20
  21 // CacheGenerator::pkgCacheGenerator - Constructor                      /*{{{*/
  22 // ---------------------------------------------------------------------
  23 /* We set the diry flag and make sure that is written to the disk */
  24 pkgCacheGenerator::pkgCacheGenerator(DynamicMMap &Map) : Map(Map), Cache(Map)
  25 {
  26    if (_error->PendingError() == true)
  27       return;
  28
  29    if (Map.Size() == 0)
  30    {
  31       Map.RawAllocate(sizeof(pkgCache::Header));
  32       *Cache.HeaderP = pkgCache::Header();
  33    }
  34    Cache.HeaderP->Dirty = true;
  35    Map.Sync(0,sizeof(pkgCache::Header));
  36    Map.UsePools(*Cache.HeaderP->Pools,sizeof(Cache.HeaderP->Pools)/sizeof(Cache.HeaderP->Pools[0]));
  37 }
  38                                                                         /*}}}*/
  39 // CacheGenerator::~pkgCacheGenerator - Destructor                      /*{{{*/
  40 // ---------------------------------------------------------------------
  41 /* We sync the data then unset the dirty flag in two steps so as to
  42    advoid a problem during a crash */
  43 pkgCacheGenerator::~pkgCacheGenerator()
  44 {
  45    if (_error->PendingError() == true)
  46       return;
  47    if (Map.Sync() == false)
  48       return;
  49
  50    Cache.HeaderP->Dirty = false;
  51    Map.Sync(0,sizeof(pkgCache::Header));
  52 }
  53                                                                         /*}}}*/
  54 // CacheGenerator::MergeList - Merge the package list                   /*{{{*/
  55 // ---------------------------------------------------------------------
  56 /* This provides the generation of the entries in the cache. Each loop
  57    goes through a single package record from the underlying parse engine. */
  58 bool pkgCacheGenerator::MergeList(ListParser &List)
  59 {
  60    List.Owner = this;
  61
  62    while (List.Step() == true)
  63    {
  64       // Get a pointer to the package structure
  65       string Package = List.Package();
  66       pkgCache::PkgIterator Pkg = Cache.FindPkg(Package);
  67       if (Pkg.end() == true)
  68       {
  69          if (NewPackage(Pkg,Package) == false)
  70             return false;
  71       }
  72
  73       /* Get a pointer to the version structure. We know the list is sorted
  74          so we use that fact in the search. Insertion of new versions is
  75          done with correct sorting */
  76       string Version = List.Version();
  77       if (Version.empty() == true)
  78       {
  79          if (List.UsePackage(Pkg,pkgCache::VerIterator(Cache)) == false)
  80             return false;
  81          continue;
  82       }
  83
  84       pkgCache::VerIterator Ver = Pkg.VersionList();
  85       unsigned long *Last = &Pkg->VersionList;
  86       int Res;
  87       for (; Ver.end() == false; Last = &Ver->NextVer, Ver++)
  88       {
  89          Res = pkgVersionCompare(Version.begin(),Version.end(),Ver.VerStr(),
  90                                  Ver.VerStr() + strlen(Ver.VerStr()));
  91          if (Res >= 0)
  92             break;
  93       }
  94
  95       /* We already have a version for this item, record that we
  96          saw it */
  97       if (Res == 0)
  98       {
  99          if (List.UsePackage(Pkg,Ver) == false)
 100             return false;
 101
 102          if (NewFileVer(Ver,List) == false)
 103             return false;
 104
 105          continue;
 106       }
 107
 108       // Add a new version
 109       *Last = NewVersion(Ver,Version,*Last);
 110       Ver->ParentPkg = Pkg.Index();
 111       if (List.NewVersion(Ver) == false)
 112          return false;
 113
 114       if (List.UsePackage(Pkg,Ver) == false)
 115          return false;
 116
 117       if (NewFileVer(Ver,List) == false)
 118          return false;
 119    }
 120
 121    return true;
 122 }
 123                                                                         /*}}}*/
 124 // CacheGenerator::NewPackage - Add a new package                       /*{{{*/
 125 // ---------------------------------------------------------------------
 126 /* This creates a new package structure and adds it to the hash table */
 127 bool pkgCacheGenerator::NewPackage(pkgCache::PkgIterator &Pkg,string Name)
 128 {
 129    // Get a structure
 130    unsigned long Package = Map.Allocate(sizeof(pkgCache::Package));
 131    if (Package == 0)
 132       return false;
 133
 134    Pkg = pkgCache::PkgIterator(Cache,Cache.PkgP + Package);
 135
 136    // Insert it into the hash table
 137    unsigned long Hash = Cache.Hash(Name);
 138    Pkg->NextPackage = Cache.HeaderP->HashTable[Hash];
 139    Cache.HeaderP->HashTable[Hash] = Package;
 140
 141    // Set the name and the ID
 142    Pkg->Name = Map.WriteString(Name);
 143    if (Pkg->Name == 0)
 144       return false;
 145    Pkg->ID = Cache.HeaderP->PackageCount++;
 146
 147    return true;
 148 }
 149                                                                         /*}}}*/
 150 // CacheGenerator::NewFileVer - Create a new File<->Version association /*{{{*/
 151 // ---------------------------------------------------------------------
 152 /* */
 153 bool pkgCacheGenerator::NewFileVer(pkgCache::VerIterator &Ver,
 154                                    ListParser &List)
 155 {
 156    // Get a structure
 157    unsigned long VerFile = Map.Allocate(sizeof(pkgCache::VerFile));
 158    if (VerFile == 0)
 159       return 0;
 160
 161    pkgCache::VerFileIterator VF(Cache,Cache.VerFileP + VerFile);
 162    VF->File = CurrentFile - Cache.PkgFileP;
 163    VF->NextFile = Ver->FileList;
 164    Ver->FileList = VF.Index();
 165    VF->Offset = List.Offset();
 166    VF->Size = List.Size();
 167
 168    return true;
 169 }
 170                                                                         /*}}}*/
 171 // CacheGenerator::NewVersion - Create a new Version                    /*{{{*/
 172 // ---------------------------------------------------------------------
 173 /* This puts a version structure in the linked list */
 174 unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver,
 175                                             string VerStr,
 176                                             unsigned long Next)
 177 {
 178    // Get a structure
 179    unsigned long Version = Map.Allocate(sizeof(pkgCache::Version));
 180    if (Version == 0)
 181       return 0;
 182
 183    // Fill it in
 184    Ver = pkgCache::VerIterator(Cache,Cache.VerP + Version);
 185    Ver->NextVer = Next;
 186    Ver->ID = Cache.HeaderP->VersionCount++;
 187    Ver->VerStr = Map.WriteString(VerStr);
 188    if (Ver->VerStr == 0)
 189       return 0;
 190
 191    return Version;
 192 }
 193                                                                         /*}}}*/
 194 // ListParser::NewDepends - Create a dependency element                 /*{{{*/
 195 // ---------------------------------------------------------------------
 196 /* This creates a dependency element in the tree. It is linked to the
 197    version and to the package that it is pointing to. */
 198 bool pkgCacheGenerator::ListParser::NewDepends(pkgCache::VerIterator Ver,
 199                                                string Package,string Version,
 200                                                unsigned int Op,
 201                                                unsigned int Type)
 202 {
 203    pkgCache &Cache = Owner->Cache;
 204
 205    // Get a structure
 206    unsigned long Dependency = Owner->Map.Allocate(sizeof(pkgCache::Dependency));
 207    if (Dependency == 0)
 208       return false;
 209
 210    // Fill it in
 211    pkgCache::DepIterator Dep(Cache,Cache.DepP + Dependency);
 212    Dep->ParentVer = Ver.Index();
 213    Dep->Type = Type;
 214    Dep->CompareOp = Op;
 215    Dep->ID = Cache.HeaderP->DependsCount++;
 216
 217    // Locate the target package
 218    pkgCache::PkgIterator Pkg = Cache.FindPkg(Package);
 219    if (Pkg.end() == true)
 220       if (Owner->NewPackage(Pkg,Package) == false)
 221          return false;
 222
 223    // Probe the reverse dependency list for a version string that matches
 224    if (Version.empty() == false)
 225    {
 226       for (pkgCache::DepIterator I = Pkg.RevDependsList(); I.end() == false; I++)
 227          if (I->Version != 0 && I.TargetVer() == Version)
 228             Dep->Version = I->Version;
 229       if (Dep->Version == 0)
 230          if ((Dep->Version = WriteString(Version)) == 0)
 231             return false;
 232    }
 233
 234    // Link it to the package
 235    Dep->Package = Pkg.Index();
 236    Dep->NextRevDepends = Pkg->RevDepends;
 237    Pkg->RevDepends = Dep.Index();
 238
 239    // Link it to the version (at the end of the list)
 240    unsigned long *Last = &Ver->DependsList;
 241    for (pkgCache::DepIterator D = Ver.DependsList(); D.end() == false; D++)
 242       Last = &D->NextDepends;
 243    Dep->NextDepends = *Last;
 244    *Last = Dep.Index();
 245
 246    return true;
 247 }
 248                                                                         /*}}}*/
 249 // ListParser::NewProvides - Create a Provides element                  /*{{{*/
 250 // ---------------------------------------------------------------------
 251 /* */
 252 bool pkgCacheGenerator::ListParser::NewProvides(pkgCache::VerIterator Ver,
 253                                                string Package,string Version)
 254 {
 255    pkgCache &Cache = Owner->Cache;
 256
 257    // Get a structure
 258    unsigned long Provides = Owner->Map.Allocate(sizeof(pkgCache::Provides));
 259    if (Provides == 0)
 260       return false;
 261
 262    // Fill it in
 263    pkgCache::PrvIterator Prv(Cache,Cache.ProvideP + Provides,Cache.PkgP);
 264    Prv->Version = Ver.Index();
 265    Prv->NextPkgProv = Ver->ProvidesList;
 266    Ver->ProvidesList = Prv.Index();
 267    if (Version.empty() == false && (Prv->Version = WriteString(Version)) == 0)
 268       return false;
 269
 270    // Locate the target package
 271    pkgCache::PkgIterator Pkg = Cache.FindPkg(Package);
 272    if (Pkg.end() == true)
 273       if (Owner->NewPackage(Pkg,Package) == false)
 274          return false;
 275
 276    // Link it to the package
 277    Prv->ParentPkg = Pkg.Index();
 278    Prv->NextProvides = Pkg->ProvidesList;
 279    Pkg->ProvidesList = Prv.Index();
 280
 281    return true;
 282 }
 283                                                                         /*}}}*/
 284 // CacheGenerator::SelectFile - Select the current file being parsed    /*{{{*/
 285 // ---------------------------------------------------------------------
 286 /* This is used to select which file is to be associated with all newly
 287    added versions. */
 288 bool pkgCacheGenerator::SelectFile(string File,unsigned long Flags)
 289 {
 290    struct stat Buf;
 291    if (stat(File.c_str(),&Buf) == -1)
 292       return _error->Errno("stat","Couldn't stat ",File.c_str());
 293
 294    // Get some space for the structure
 295    CurrentFile = Cache.PkgFileP + Map.Allocate(sizeof(*CurrentFile));
 296    if (CurrentFile == Cache.PkgFileP)
 297       return false;
 298
 299    // Fill it in
 300    CurrentFile->FileName = Map.WriteString(File);
 301    CurrentFile->Size = Buf.st_size;
 302    CurrentFile->mtime = Buf.st_mtime;
 303    CurrentFile->NextFile = Cache.HeaderP->FileList;
 304    CurrentFile->Flags = Flags;
 305    PkgFileName = File;
 306
 307    if (CurrentFile->FileName == 0)
 308       return false;
 309 }
 310                                                                         /*}}}*/
 311 // CacheGenerator::WriteUniqueString - Insert a unique string           /*{{{*/
 312 // ---------------------------------------------------------------------
 313 /* This is used to create handles to strings. Given the same text it
 314    always returns the same number */
 315 unsigned long pkgCacheGenerator::WriteUniqString(const char *S,
 316                                                  unsigned int Size)
 317 {
 318    // Search for an insertion point
 319    pkgCache::StringItem *I = Cache.StringItemP + Cache.HeaderP->StringList;
 320    int Res = 1;
 321    unsigned long *Last = &Cache.HeaderP->StringList;
 322    for (; I != Cache.StringItemP; Last = &I->NextItem,
 323         I = Cache.StringItemP + I->NextItem)
 324    {
 325       Res = strncmp(Cache.StrP + I->String,S,Size);
 326       if (Res == 0 && *(Cache.StrP + I->String + Size) != 0)
 327          Res = 1;
 328       if (Res >= 0)
 329          break;
 330    }
 331
 332    // Match
 333    if (Res == 0)
 334       return I->String;
 335
 336    // Get a structure
 337    unsigned long Item = Map.Allocate(sizeof(pkgCache::StringItem));
 338    if (Item == 0)
 339       return 0;
 340
 341    // Fill in the structure
 342    pkgCache::StringItem *ItemP = Cache.StringItemP + Item;
 343    ItemP->NextItem = I - Cache.StringItemP;
 344    *Last = Item;
 345    ItemP->String = Map.WriteString(S,Size);
 346    if (ItemP->String == 0)
 347       return 0;
 348
 349    return ItemP->String;
 350 }
 351                                                                         /*}}}*/