apt-pkg/pkgcache.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: pkgcache.cc,v 1.37 2003/02/10 01:40:58 doogie Exp $
   4 /* ######################################################################
   5
   6    Package Cache - Accessor code for the cache
   7
   8    Please see doc/apt-pkg/cache.sgml for a more detailed description of
   9    this format. Also be sure to keep that file up-to-date!!
  10
  11    This is the general utility functions for cache managment. They provide
  12    a complete set of accessor functions for the cache. The cacheiterators
  13    header contains the STL-like iterators that can be used to easially
  14    navigate the cache as well as seemlessly dereference the mmap'd
  15    indexes. Use these always.
  16
  17    The main class provides for ways to get package indexes and some
  18    general lookup functions to start the iterators.
  19
  20    ##################################################################### */
  21                                                                         /*}}}*/
  22 // Include Files                                                        /*{{{*/
  23 #include <apt-pkg/pkgcache.h>
  24 #include <apt-pkg/policy.h>
  25 #include <apt-pkg/version.h>
  26 #include <apt-pkg/error.h>
  27 #include <apt-pkg/strutl.h>
  28 #include <apt-pkg/configuration.h>
  29 #include <apt-pkg/aptconfiguration.h>
  30 #include <apt-pkg/macros.h>
  31
  32 #include <apti18n.h>
  33
  34 #include <string>
  35 #include <sys/stat.h>
  36 #include <unistd.h>
  37
  38 #include <ctype.h>
  39                                                                         /*}}}*/
  40
  41 using std::string;
  42
  43
  44 // Cache::Header::Header - Constructor                                  /*{{{*/
  45 // ---------------------------------------------------------------------
  46 /* Simply initialize the header */
  47 pkgCache::Header::Header()
  48 {
  49    Signature = 0x98FE76DC;
  50
  51    /* Whenever the structures change the major version should be bumped,
  52       whenever the generator changes the minor version should be bumped. */
  53    MajorVersion = 8;
  54    MinorVersion = 0;
  55    Dirty = false;
  56
  57    HeaderSz = sizeof(pkgCache::Header);
  58    GroupSz = sizeof(pkgCache::Group);
  59    PackageSz = sizeof(pkgCache::Package);
  60    PackageFileSz = sizeof(pkgCache::PackageFile);
  61    VersionSz = sizeof(pkgCache::Version);
  62    DescriptionSz = sizeof(pkgCache::Description);
  63    DependencySz = sizeof(pkgCache::Dependency);
  64    ProvidesSz = sizeof(pkgCache::Provides);
  65    VerFileSz = sizeof(pkgCache::VerFile);
  66    DescFileSz = sizeof(pkgCache::DescFile);
  67
  68    GroupCount = 0;
  69    PackageCount = 0;
  70    VersionCount = 0;
  71    DescriptionCount = 0;
  72    DependsCount = 0;
  73    PackageFileCount = 0;
  74    VerFileCount = 0;
  75    DescFileCount = 0;
  76    ProvidesCount = 0;
  77    MaxVerFileSize = 0;
  78    MaxDescFileSize = 0;
  79
  80    FileList = 0;
  81    StringList = 0;
  82    VerSysName = 0;
  83    Architecture = 0;
  84    memset(PkgHashTable,0,sizeof(PkgHashTable));
  85    memset(GrpHashTable,0,sizeof(GrpHashTable));
  86    memset(Pools,0,sizeof(Pools));
  87 }
  88                                                                         /*}}}*/
  89 // Cache::Header::CheckSizes - Check if the two headers have same *sz   /*{{{*/
  90 // ---------------------------------------------------------------------
  91 /* */
  92 bool pkgCache::Header::CheckSizes(Header &Against) const
  93 {
  94    if (HeaderSz == Against.HeaderSz &&
  95        GroupSz == Against.GroupSz &&
  96        PackageSz == Against.PackageSz &&
  97        PackageFileSz == Against.PackageFileSz &&
  98        VersionSz == Against.VersionSz &&
  99        DescriptionSz == Against.DescriptionSz &&
 100        DependencySz == Against.DependencySz &&
 101        VerFileSz == Against.VerFileSz &&
 102        DescFileSz == Against.DescFileSz &&
 103        ProvidesSz == Against.ProvidesSz)
 104       return true;
 105    return false;
 106 }
 107                                                                         /*}}}*/
 108
 109 // Cache::pkgCache - Constructor                                        /*{{{*/
 110 // ---------------------------------------------------------------------
 111 /* */
 112 pkgCache::pkgCache(MMap *Map, bool DoMap) : Map(*Map)
 113 {
 114    // call getArchitectures() with cached=false to ensure that the
 115    // architectures cache is re-evaulated. this is needed in cases
 116    // when the APT::Architecture field changes between two cache creations
 117    MultiArchEnabled = APT::Configuration::getArchitectures(false).size() > 1;
 118    if (DoMap == true)
 119       ReMap();
 120 }
 121                                                                         /*}}}*/
 122 // Cache::ReMap - Reopen the cache file                                 /*{{{*/
 123 // ---------------------------------------------------------------------
 124 /* If the file is already closed then this will open it open it. */
 125 bool pkgCache::ReMap(bool const &Errorchecks)
 126 {
 127    // Apply the typecasts.
 128    HeaderP = (Header *)Map.Data();
 129    GrpP = (Group *)Map.Data();
 130    PkgP = (Package *)Map.Data();
 131    VerFileP = (VerFile *)Map.Data();
 132    DescFileP = (DescFile *)Map.Data();
 133    PkgFileP = (PackageFile *)Map.Data();
 134    VerP = (Version *)Map.Data();
 135    DescP = (Description *)Map.Data();
 136    ProvideP = (Provides *)Map.Data();
 137    DepP = (Dependency *)Map.Data();
 138    StringItemP = (StringItem *)Map.Data();
 139    StrP = (char *)Map.Data();
 140
 141    if (Errorchecks == false)
 142       return true;
 143
 144    if (Map.Size() == 0 || HeaderP == 0)
 145       return _error->Error(_("Empty package cache"));
 146
 147    // Check the header
 148    Header DefHeader;
 149    if (HeaderP->Signature != DefHeader.Signature ||
 150        HeaderP->Dirty == true)
 151       return _error->Error(_("The package cache file is corrupted"));
 152
 153    if (HeaderP->MajorVersion != DefHeader.MajorVersion ||
 154        HeaderP->MinorVersion != DefHeader.MinorVersion ||
 155        HeaderP->CheckSizes(DefHeader) == false)
 156       return _error->Error(_("The package cache file is an incompatible version"));
 157
 158    // Locate our VS..
 159    if (HeaderP->VerSysName == 0 ||
 160        (VS = pkgVersioningSystem::GetVS(StrP + HeaderP->VerSysName)) == 0)
 161       return _error->Error(_("This APT does not support the versioning system '%s'"),StrP + HeaderP->VerSysName);
 162
 163    // Chcek the arhcitecture
 164    if (HeaderP->Architecture == 0 ||
 165        _config->Find("APT::Architecture") != StrP + HeaderP->Architecture)
 166       return _error->Error(_("The package cache was built for a different architecture"));
 167    return true;
 168 }
 169                                                                         /*}}}*/
 170 // Cache::Hash - Hash a string                                          /*{{{*/
 171 // ---------------------------------------------------------------------
 172 /* This is used to generate the hash entries for the HashTable. With my
 173    package list from bo this function gets 94% table usage on a 512 item
 174    table (480 used items) */
 175 unsigned long pkgCache::sHash(const string &Str) const
 176 {
 177    unsigned long Hash = 0;
 178    for (string::const_iterator I = Str.begin(); I != Str.end(); I++)
 179       Hash = 5*Hash + tolower_ascii(*I);
 180    return Hash % _count(HeaderP->PkgHashTable);
 181 }
 182
 183 unsigned long pkgCache::sHash(const char *Str) const
 184 {
 185    unsigned long Hash = 0;
 186    for (const char *I = Str; *I != 0; I++)
 187       Hash = 5*Hash + tolower_ascii(*I);
 188    return Hash % _count(HeaderP->PkgHashTable);
 189 }
 190
 191                                                                         /*}}}*/
 192 // Cache::SingleArchFindPkg - Locate a package by name                  /*{{{*/
 193 // ---------------------------------------------------------------------
 194 /* Returns 0 on error, pointer to the package otherwise
 195    The multiArch enabled methods will fallback to this one as it is (a bit)
 196    faster for single arch environments and realworld is mostly singlearch… */
 197 pkgCache::PkgIterator pkgCache::SingleArchFindPkg(const string &Name)
 198 {
 199    // Look at the hash bucket
 200    Package *Pkg = PkgP + HeaderP->PkgHashTable[Hash(Name)];
 201    for (; Pkg != PkgP; Pkg = PkgP + Pkg->NextPackage)
 202    {
 203       if (Pkg->Name != 0 && StrP[Pkg->Name] == Name[0] &&
 204           stringcasecmp(Name,StrP + Pkg->Name) == 0)
 205          return PkgIterator(*this,Pkg);
 206    }
 207    return PkgIterator(*this,0);
 208 }
 209                                                                         /*}}}*/
 210 // Cache::FindPkg - Locate a package by name                            /*{{{*/
 211 // ---------------------------------------------------------------------
 212 /* Returns 0 on error, pointer to the package otherwise */
 213 pkgCache::PkgIterator pkgCache::FindPkg(const string &Name) {
 214         if (MultiArchCache() == false)
 215                 return SingleArchFindPkg(Name);
 216         size_t const found = Name.find(':');
 217         if (found == string::npos)
 218                 return FindPkg(Name, "native");
 219         string const Arch = Name.substr(found+1);
 220         if (Arch == "any")
 221                 return FindPkg(Name, "any");
 222         return FindPkg(Name.substr(0, found), Arch);
 223 }
 224                                                                         /*}}}*/
 225 // Cache::FindPkg - Locate a package by name                            /*{{{*/
 226 // ---------------------------------------------------------------------
 227 /* Returns 0 on error, pointer to the package otherwise */
 228 pkgCache::PkgIterator pkgCache::FindPkg(const string &Name, string const &Arch) {
 229         if (MultiArchCache() == false) {
 230                 if (Arch == "native" || Arch == "all" || Arch == "any" ||
 231                     Arch == _config->Find("APT::Architecture"))
 232                         return SingleArchFindPkg(Name);
 233                 else
 234                         return PkgIterator(*this,0);
 235         }
 236         /* We make a detour via the GrpIterator here as
 237            on a multi-arch environment a group is easier to
 238            find than a package (less entries in the buckets) */
 239         pkgCache::GrpIterator Grp = FindGrp(Name);
 240         if (Grp.end() == true)
 241                 return PkgIterator(*this,0);
 242
 243         return Grp.FindPkg(Arch);
 244 }
 245                                                                         /*}}}*/
 246 // Cache::FindGrp - Locate a group by name                              /*{{{*/
 247 // ---------------------------------------------------------------------
 248 /* Returns End-Pointer on error, pointer to the group otherwise */
 249 pkgCache::GrpIterator pkgCache::FindGrp(const string &Name) {
 250         if (unlikely(Name.empty() == true))
 251                 return GrpIterator(*this,0);
 252
 253         // Look at the hash bucket for the group
 254         Group *Grp = GrpP + HeaderP->GrpHashTable[sHash(Name)];
 255         for (; Grp != GrpP; Grp = GrpP + Grp->Next) {
 256                 if (Grp->Name != 0 && StrP[Grp->Name] == Name[0] &&
 257                     stringcasecmp(Name, StrP + Grp->Name) == 0)
 258                         return GrpIterator(*this, Grp);
 259         }
 260
 261         return GrpIterator(*this,0);
 262 }
 263                                                                         /*}}}*/
 264 // Cache::CompTypeDeb - Return a string describing the compare type     /*{{{*/
 265 // ---------------------------------------------------------------------
 266 /* This returns a string representation of the dependency compare
 267    type in the weird debian style.. */
 268 const char *pkgCache::CompTypeDeb(unsigned char Comp)
 269 {
 270    const char *Ops[] = {"","<=",">=","<<",">>","=","!="};
 271    if ((unsigned)(Comp & 0xF) < 7)
 272       return Ops[Comp & 0xF];
 273    return "";
 274 }
 275                                                                         /*}}}*/
 276 // Cache::CompType - Return a string describing the compare type        /*{{{*/
 277 // ---------------------------------------------------------------------
 278 /* This returns a string representation of the dependency compare
 279    type */
 280 const char *pkgCache::CompType(unsigned char Comp)
 281 {
 282    const char *Ops[] = {"","<=",">=","<",">","=","!="};
 283    if ((unsigned)(Comp & 0xF) < 7)
 284       return Ops[Comp & 0xF];
 285    return "";
 286 }
 287                                                                         /*}}}*/
 288 // Cache::DepType - Return a string describing the dep type             /*{{{*/
 289 // ---------------------------------------------------------------------
 290 /* */
 291 const char *pkgCache::DepType(unsigned char Type)
 292 {
 293    const char *Types[] = {"",_("Depends"),_("PreDepends"),_("Suggests"),
 294                           _("Recommends"),_("Conflicts"),_("Replaces"),
 295                           _("Obsoletes"),_("Breaks"), _("Enhances")};
 296    if (Type < sizeof(Types)/sizeof(*Types))
 297       return Types[Type];
 298    return "";
 299 }
 300                                                                         /*}}}*/
 301 // Cache::Priority - Convert a priority value to a string               /*{{{*/
 302 // ---------------------------------------------------------------------
 303 /* */
 304 const char *pkgCache::Priority(unsigned char Prio)
 305 {
 306    const char *Mapping[] = {0,_("important"),_("required"),_("standard"),
 307                             _("optional"),_("extra")};
 308    if (Prio < _count(Mapping))
 309       return Mapping[Prio];
 310    return 0;
 311 }
 312                                                                         /*}}}*/
 313 // GrpIterator::FindPkg - Locate a package by arch                      /*{{{*/
 314 // ---------------------------------------------------------------------
 315 /* Returns an End-Pointer on error, pointer to the package otherwise */
 316 pkgCache::PkgIterator pkgCache::GrpIterator::FindPkg(string Arch) const {
 317         if (unlikely(IsGood() == false || S->FirstPackage == 0))
 318                 return PkgIterator(*Owner, 0);
 319
 320         static string const myArch = _config->Find("APT::Architecture");
 321         /* Most of the time the package for our native architecture is
 322            the one we add at first to the cache, but this would be the
 323            last one we check, so we do it now. */
 324         if (Arch == "native" || Arch == myArch) {
 325                 Arch = myArch;
 326                 pkgCache::Package *Pkg = Owner->PkgP + S->LastPackage;
 327                 if (stringcasecmp(Arch, Owner->StrP + Pkg->Arch) == 0)
 328                         return PkgIterator(*Owner, Pkg);
 329         }
 330
 331         /* If we accept any package we simply return the "first"
 332            package in this group (the last one added). */
 333         if (Arch == "any")
 334                 return PkgIterator(*Owner, Owner->PkgP + S->FirstPackage);
 335
 336         /* Iterate over the list to find the matching arch
 337            unfortunately this list includes "package noise"
 338            (= different packages with same calculated hash),
 339            so we need to check the name also */
 340         for (pkgCache::Package *Pkg = PackageList(); Pkg != Owner->PkgP;
 341              Pkg = Owner->PkgP + Pkg->NextPackage) {
 342                 if (S->Name == Pkg->Name &&
 343                     stringcasecmp(Arch, Owner->StrP + Pkg->Arch) == 0)
 344                         return PkgIterator(*Owner, Pkg);
 345                 if ((Owner->PkgP + S->LastPackage) == Pkg)
 346                         break;
 347         }
 348
 349         return PkgIterator(*Owner, 0);
 350 }
 351                                                                         /*}}}*/
 352 // GrpIterator::FindPreferredPkg - Locate the "best" package            /*{{{*/
 353 // ---------------------------------------------------------------------
 354 /* Returns an End-Pointer on error, pointer to the package otherwise */
 355 pkgCache::PkgIterator pkgCache::GrpIterator::FindPreferredPkg(bool const &PreferNonVirtual) const {
 356         pkgCache::PkgIterator Pkg = FindPkg("native");
 357         if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 358                 return Pkg;
 359
 360         std::vector<std::string> const archs = APT::Configuration::getArchitectures();
 361         for (std::vector<std::string>::const_iterator a = archs.begin();
 362              a != archs.end(); ++a) {
 363                 Pkg = FindPkg(*a);
 364                 if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 365                         return Pkg;
 366         }
 367
 368         if (PreferNonVirtual == true)
 369                 return FindPreferredPkg(false);
 370         return PkgIterator(*Owner, 0);
 371 }
 372                                                                         /*}}}*/
 373 // GrpIterator::NextPkg - Locate the next package in the group          /*{{{*/
 374 // ---------------------------------------------------------------------
 375 /* Returns an End-Pointer on error, pointer to the package otherwise.
 376    We can't simply ++ to the next as the next package of the last will
 377    be from a different group (with the same hash value) */
 378 pkgCache::PkgIterator pkgCache::GrpIterator::NextPkg(pkgCache::PkgIterator const &LastPkg) const {
 379         if (unlikely(IsGood() == false || S->FirstPackage == 0 ||
 380             LastPkg.end() == true))
 381                 return PkgIterator(*Owner, 0);
 382
 383         if (S->LastPackage == LastPkg.Index())
 384                 return PkgIterator(*Owner, 0);
 385
 386         return PkgIterator(*Owner, Owner->PkgP + LastPkg->NextPackage);
 387 }
 388                                                                         /*}}}*/
 389 // GrpIterator::operator ++ - Postfix incr                              /*{{{*/
 390 // ---------------------------------------------------------------------
 391 /* This will advance to the next logical group in the hash table. */
 392 void pkgCache::GrpIterator::operator ++(int)
 393 {
 394    // Follow the current links
 395    if (S != Owner->GrpP)
 396       S = Owner->GrpP + S->Next;
 397
 398    // Follow the hash table
 399    while (S == Owner->GrpP && (HashIndex+1) < (signed)_count(Owner->HeaderP->GrpHashTable))
 400    {
 401       HashIndex++;
 402       S = Owner->GrpP + Owner->HeaderP->GrpHashTable[HashIndex];
 403    }
 404 };
 405                                                                         /*}}}*/
 406 // PkgIterator::operator ++ - Postfix incr                              /*{{{*/
 407 // ---------------------------------------------------------------------
 408 /* This will advance to the next logical package in the hash table. */
 409 void pkgCache::PkgIterator::operator ++(int)
 410 {
 411    // Follow the current links
 412    if (S != Owner->PkgP)
 413       S = Owner->PkgP + S->NextPackage;
 414
 415    // Follow the hash table
 416    while (S == Owner->PkgP && (HashIndex+1) < (signed)_count(Owner->HeaderP->PkgHashTable))
 417    {
 418       HashIndex++;
 419       S = Owner->PkgP + Owner->HeaderP->PkgHashTable[HashIndex];
 420    }
 421 };
 422                                                                         /*}}}*/
 423 // PkgIterator::State - Check the State of the package                  /*{{{*/
 424 // ---------------------------------------------------------------------
 425 /* By this we mean if it is either cleanly installed or cleanly removed. */
 426 pkgCache::PkgIterator::OkState pkgCache::PkgIterator::State() const
 427 {
 428    if (S->InstState == pkgCache::State::ReInstReq ||
 429        S->InstState == pkgCache::State::HoldReInstReq)
 430       return NeedsUnpack;
 431
 432    if (S->CurrentState == pkgCache::State::UnPacked ||
 433        S->CurrentState == pkgCache::State::HalfConfigured)
 434       // we leave triggers alone complettely. dpkg deals with
 435       // them in a hard-to-predict manner and if they get
 436       // resolved by dpkg before apt run dpkg --configure on
 437       // the TriggersPending package dpkg returns a error
 438       //Pkg->CurrentState == pkgCache::State::TriggersAwaited
 439       //Pkg->CurrentState == pkgCache::State::TriggersPending)
 440       return NeedsConfigure;
 441
 442    if (S->CurrentState == pkgCache::State::HalfInstalled ||
 443        S->InstState != pkgCache::State::Ok)
 444       return NeedsUnpack;
 445
 446    return NeedsNothing;
 447 }
 448                                                                         /*}}}*/
 449 // PkgIterator::CandVersion - Returns the candidate version string      /*{{{*/
 450 // ---------------------------------------------------------------------
 451 /* Return string representing of the candidate version. */
 452 const char *
 453 pkgCache::PkgIterator::CandVersion() const
 454 {
 455   //TargetVer is empty, so don't use it.
 456   VerIterator version = pkgPolicy(Owner).GetCandidateVer(*this);
 457   if (version.IsGood())
 458     return version.VerStr();
 459   return 0;
 460 };
 461                                                                         /*}}}*/
 462 // PkgIterator::CurVersion - Returns the current version string         /*{{{*/
 463 // ---------------------------------------------------------------------
 464 /* Return string representing of the current version. */
 465 const char *
 466 pkgCache::PkgIterator::CurVersion() const
 467 {
 468   VerIterator version = CurrentVer();
 469   if (version.IsGood())
 470     return CurrentVer().VerStr();
 471   return 0;
 472 };
 473                                                                         /*}}}*/
 474 // ostream operator to handle string representation of a package        /*{{{*/
 475 // ---------------------------------------------------------------------
 476 /* Output name < cur.rent.version -> candid.ate.version | new.est.version > (section)
 477    Note that the characters <|>() are all literal above. Versions will be ommited
 478    if they provide no new information (e.g. there is no newer version than candidate)
 479    If no version and/or section can be found "none" is used. */
 480 std::ostream&
 481 operator<<(ostream& out, pkgCache::PkgIterator Pkg)
 482 {
 483    if (Pkg.end() == true)
 484       return out << "invalid package";
 485
 486    string current = string(Pkg.CurVersion() == 0 ? "none" : Pkg.CurVersion());
 487    string candidate = string(Pkg.CandVersion() == 0 ? "none" : Pkg.CandVersion());
 488    string newest = string(Pkg.VersionList().end() ? "none" : Pkg.VersionList().VerStr());
 489
 490    out << Pkg.Name() << " [ " << Pkg.Arch() << " ] < " << current;
 491    if (current != candidate)
 492       out << " -> " << candidate;
 493    if ( newest != "none" && candidate != newest)
 494       out << " | " << newest;
 495    out << " > ( " << string(Pkg.Section()==0?"none":Pkg.Section()) << " )";
 496    return out;
 497 }
 498                                                                         /*}}}*/
 499 // PkgIterator::FullName - Returns Name and (maybe) Architecture        /*{{{*/
 500 // ---------------------------------------------------------------------
 501 /* Returns a name:arch string */
 502 std::string pkgCache::PkgIterator::FullName(bool const &Pretty) const
 503 {
 504    string fullname = Name();
 505    if (Pretty == false ||
 506        (strcmp(Arch(), "all") != 0 && _config->Find("APT::Architecture") != Arch()))
 507       return fullname.append(":").append(Arch());
 508    return fullname;
 509 }
 510                                                                         /*}}}*/
 511 // DepIterator::IsCritical - Returns true if the dep is important       /*{{{*/
 512 // ---------------------------------------------------------------------
 513 /* Currently critical deps are defined as depends, predepends and
 514    conflicts (including dpkg's Breaks fields). */
 515 bool pkgCache::DepIterator::IsCritical() const
 516 {
 517    if (S->Type == pkgCache::Dep::Conflicts ||
 518        S->Type == pkgCache::Dep::DpkgBreaks ||
 519        S->Type == pkgCache::Dep::Obsoletes ||
 520        S->Type == pkgCache::Dep::Depends ||
 521        S->Type == pkgCache::Dep::PreDepends)
 522       return true;
 523    return false;
 524 }
 525                                                                         /*}}}*/
 526 // DepIterator::SmartTargetPkg - Resolve dep target pointers w/provides /*{{{*/
 527 // ---------------------------------------------------------------------
 528 /* This intellegently looks at dep target packages and tries to figure
 529    out which package should be used. This is needed to nicely handle
 530    provide mapping. If the target package has no other providing packages
 531    then it returned. Otherwise the providing list is looked at to
 532    see if there is one one unique providing package if so it is returned.
 533    Otherwise true is returned and the target package is set. The return
 534    result indicates whether the node should be expandable
 535
 536    In Conjunction with the DepCache the value of Result may not be
 537    super-good since the policy may have made it uninstallable. Using
 538    AllTargets is better in this case. */
 539 bool pkgCache::DepIterator::SmartTargetPkg(PkgIterator &Result) const
 540 {
 541    Result = TargetPkg();
 542
 543    // No provides at all
 544    if (Result->ProvidesList == 0)
 545       return false;
 546
 547    // There is the Base package and the providing ones which is at least 2
 548    if (Result->VersionList != 0)
 549       return true;
 550
 551    /* We have to skip over indirect provisions of the package that
 552       owns the dependency. For instance, if libc5-dev depends on the
 553       virtual package libc-dev which is provided by libc5-dev and libc6-dev
 554       we must ignore libc5-dev when considering the provides list. */
 555    PrvIterator PStart = Result.ProvidesList();
 556    for (; PStart.end() != true && PStart.OwnerPkg() == ParentPkg(); PStart++);
 557
 558    // Nothing but indirect self provides
 559    if (PStart.end() == true)
 560       return false;
 561
 562    // Check for single packages in the provides list
 563    PrvIterator P = PStart;
 564    for (; P.end() != true; P++)
 565    {
 566       // Skip over self provides
 567       if (P.OwnerPkg() == ParentPkg())
 568          continue;
 569       if (PStart.OwnerPkg() != P.OwnerPkg())
 570          break;
 571    }
 572
 573    Result = PStart.OwnerPkg();
 574
 575    // Check for non dups
 576    if (P.end() != true)
 577       return true;
 578
 579    return false;
 580 }
 581                                                                         /*}}}*/
 582 // DepIterator::AllTargets - Returns the set of all possible targets    /*{{{*/
 583 // ---------------------------------------------------------------------
 584 /* This is a more useful version of TargetPkg() that follows versioned
 585    provides. It includes every possible package-version that could satisfy
 586    the dependency. The last item in the list has a 0. The resulting pointer
 587    must be delete [] 'd */
 588 pkgCache::Version **pkgCache::DepIterator::AllTargets() const
 589 {
 590    Version **Res = 0;
 591    unsigned long Size =0;
 592    while (1)
 593    {
 594       Version **End = Res;
 595       PkgIterator DPkg = TargetPkg();
 596
 597       // Walk along the actual package providing versions
 598       for (VerIterator I = DPkg.VersionList(); I.end() == false; I++)
 599       {
 600          if (Owner->VS->CheckDep(I.VerStr(),S->CompareOp,TargetVer()) == false)
 601             continue;
 602
 603          if ((S->Type == pkgCache::Dep::Conflicts ||
 604               S->Type == pkgCache::Dep::DpkgBreaks ||
 605               S->Type == pkgCache::Dep::Obsoletes) &&
 606              ParentPkg() == I.ParentPkg())
 607             continue;
 608
 609          Size++;
 610          if (Res != 0)
 611             *End++ = I;
 612       }
 613
 614       // Follow all provides
 615       for (PrvIterator I = DPkg.ProvidesList(); I.end() == false; I++)
 616       {
 617          if (Owner->VS->CheckDep(I.ProvideVersion(),S->CompareOp,TargetVer()) == false)
 618             continue;
 619
 620          if ((S->Type == pkgCache::Dep::Conflicts ||
 621               S->Type == pkgCache::Dep::DpkgBreaks ||
 622               S->Type == pkgCache::Dep::Obsoletes) &&
 623              ParentPkg() == I.OwnerPkg())
 624             continue;
 625
 626          Size++;
 627          if (Res != 0)
 628             *End++ = I.OwnerVer();
 629       }
 630
 631       // Do it again and write it into the array
 632       if (Res == 0)
 633       {
 634          Res = new Version *[Size+1];
 635          Size = 0;
 636       }
 637       else
 638       {
 639          *End = 0;
 640          break;
 641       }
 642    }
 643
 644    return Res;
 645 }
 646                                                                         /*}}}*/
 647 // DepIterator::GlobOr - Compute an OR group                            /*{{{*/
 648 // ---------------------------------------------------------------------
 649 /* This Takes an iterator, iterates past the current dependency grouping
 650    and returns Start and End so that so End is the final element
 651    in the group, if End == Start then D is End++ and End is the
 652    dependency D was pointing to. Use in loops to iterate sensibly. */
 653 void pkgCache::DepIterator::GlobOr(DepIterator &Start,DepIterator &End)
 654 {
 655    // Compute a single dependency element (glob or)
 656    Start = *this;
 657    End = *this;
 658    for (bool LastOR = true; end() == false && LastOR == true;)
 659    {
 660       LastOR = (S->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
 661       (*this)++;
 662       if (LastOR == true)
 663          End = (*this);
 664    }
 665 }
 666                                                                         /*}}}*/
 667 // VerIterator::CompareVer - Fast version compare for same pkgs         /*{{{*/
 668 // ---------------------------------------------------------------------
 669 /* This just looks over the version list to see if B is listed before A. In
 670    most cases this will return in under 4 checks, ver lists are short. */
 671 int pkgCache::VerIterator::CompareVer(const VerIterator &B) const
 672 {
 673    // Check if they are equal
 674    if (*this == B)
 675       return 0;
 676    if (end() == true)
 677       return -1;
 678    if (B.end() == true)
 679       return 1;
 680
 681    /* Start at A and look for B. If B is found then A > B otherwise
 682       B was before A so A < B */
 683    VerIterator I = *this;
 684    for (;I.end() == false; I++)
 685       if (I == B)
 686          return 1;
 687    return -1;
 688 }
 689                                                                         /*}}}*/
 690 // VerIterator::Downloadable - Checks if the version is downloadable    /*{{{*/
 691 // ---------------------------------------------------------------------
 692 /* */
 693 bool pkgCache::VerIterator::Downloadable() const
 694 {
 695    VerFileIterator Files = FileList();
 696    for (; Files.end() == false; Files++)
 697       if ((Files.File()->Flags & pkgCache::Flag::NotSource) != pkgCache::Flag::NotSource)
 698          return true;
 699    return false;
 700 }
 701                                                                         /*}}}*/
 702 // VerIterator::Automatic - Check if this version is 'automatic'        /*{{{*/
 703 // ---------------------------------------------------------------------
 704 /* This checks to see if any of the versions files are not NotAutomatic.
 705    True if this version is selectable for automatic installation. */
 706 bool pkgCache::VerIterator::Automatic() const
 707 {
 708    VerFileIterator Files = FileList();
 709    for (; Files.end() == false; Files++)
 710       if ((Files.File()->Flags & pkgCache::Flag::NotAutomatic) != pkgCache::Flag::NotAutomatic)
 711          return true;
 712    return false;
 713 }
 714                                                                         /*}}}*/
 715 // VerIterator::Pseudo - Check if this version is a pseudo one          /*{{{*/
 716 // ---------------------------------------------------------------------
 717 /* Sometimes you have the need to express dependencies with versions
 718    which doesn't really exist or exist multiply times for "different"
 719    packages. We need these versions for dependency resolution but they
 720    are a problem everytime we need to download/install something. */
 721 bool pkgCache::VerIterator::Pseudo() const
 722 {
 723    if (S->MultiArch == pkgCache::Version::All &&
 724            strcmp(Arch(true),"all") != 0)
 725    {
 726            GrpIterator const Grp = ParentPkg().Group();
 727            return (Grp->LastPackage != Grp->FirstPackage);
 728    }
 729    return false;
 730 }
 731                                                                         /*}}}*/
 732 // VerIterator::NewestFile - Return the newest file version relation    /*{{{*/
 733 // ---------------------------------------------------------------------
 734 /* This looks at the version numbers associated with all of the sources
 735    this version is in and returns the highest.*/
 736 pkgCache::VerFileIterator pkgCache::VerIterator::NewestFile() const
 737 {
 738    VerFileIterator Files = FileList();
 739    VerFileIterator Highest = Files;
 740    for (; Files.end() == false; Files++)
 741    {
 742       if (Owner->VS->CmpReleaseVer(Files.File().Version(),Highest.File().Version()) > 0)
 743          Highest = Files;
 744    }
 745
 746    return Highest;
 747 }
 748                                                                         /*}}}*/
 749 // VerIterator::RelStr - Release description string                     /*{{{*/
 750 // ---------------------------------------------------------------------
 751 /* This describes the version from a release-centric manner. The output is a
 752    list of Label:Version/Archive */
 753 string pkgCache::VerIterator::RelStr() const
 754 {
 755    bool First = true;
 756    string Res;
 757    for (pkgCache::VerFileIterator I = this->FileList(); I.end() == false; I++)
 758    {
 759       // Do not print 'not source' entries'
 760       pkgCache::PkgFileIterator File = I.File();
 761       if ((File->Flags & pkgCache::Flag::NotSource) == pkgCache::Flag::NotSource)
 762          continue;
 763
 764       // See if we have already printed this out..
 765       bool Seen = false;
 766       for (pkgCache::VerFileIterator J = this->FileList(); I != J; J++)
 767       {
 768          pkgCache::PkgFileIterator File2 = J.File();
 769          if (File2->Label == 0 || File->Label == 0)
 770             continue;
 771
 772          if (strcmp(File.Label(),File2.Label()) != 0)
 773             continue;
 774
 775          if (File2->Version == File->Version)
 776          {
 777             Seen = true;
 778             break;
 779          }
 780          if (File2->Version == 0 || File->Version == 0)
 781             break;
 782          if (strcmp(File.Version(),File2.Version()) == 0)
 783             Seen = true;
 784       }
 785
 786       if (Seen == true)
 787          continue;
 788
 789       if (First == false)
 790          Res += ", ";
 791       else
 792          First = false;
 793
 794       if (File->Label != 0)
 795          Res = Res + File.Label() + ':';
 796
 797       if (File->Archive != 0)
 798       {
 799          if (File->Version == 0)
 800             Res += File.Archive();
 801          else
 802             Res = Res + File.Version() + '/' +  File.Archive();
 803       }
 804       else
 805       {
 806          // No release file, print the host name that this came from
 807          if (File->Site == 0 || File.Site()[0] == 0)
 808             Res += "localhost";
 809          else
 810             Res += File.Site();
 811       }
 812    }
 813    if (S->ParentPkg != 0)
 814       Res.append(" [").append(Arch()).append("]");
 815    return Res;
 816 }
 817                                                                         /*}}}*/
 818 // PkgFileIterator::IsOk - Checks if the cache is in sync with the file /*{{{*/
 819 // ---------------------------------------------------------------------
 820 /* This stats the file and compares its stats with the ones that were
 821    stored during generation. Date checks should probably also be
 822    included here. */
 823 bool pkgCache::PkgFileIterator::IsOk()
 824 {
 825    struct stat Buf;
 826    if (stat(FileName(),&Buf) != 0)
 827       return false;
 828
 829    if (Buf.st_size != (signed)S->Size || Buf.st_mtime != S->mtime)
 830       return false;
 831
 832    return true;
 833 }
 834                                                                         /*}}}*/
 835 // PkgFileIterator::RelStr - Return the release string                  /*{{{*/
 836 // ---------------------------------------------------------------------
 837 /* */
 838 string pkgCache::PkgFileIterator::RelStr()
 839 {
 840    string Res;
 841    if (Version() != 0)
 842       Res = Res + (Res.empty() == true?"v=":",v=") + Version();
 843    if (Origin() != 0)
 844       Res = Res + (Res.empty() == true?"o=":",o=")  + Origin();
 845    if (Archive() != 0)
 846       Res = Res + (Res.empty() == true?"a=":",a=")  + Archive();
 847    if (Codename() != 0)
 848       Res = Res + (Res.empty() == true?"n=":",n=")  + Codename();
 849    if (Label() != 0)
 850       Res = Res + (Res.empty() == true?"l=":",l=")  + Label();
 851    if (Component() != 0)
 852       Res = Res + (Res.empty() == true?"c=":",c=")  + Component();
 853    if (Architecture() != 0)
 854       Res = Res + (Res.empty() == true?"b=":",b=")  + Architecture();
 855    return Res;
 856 }
 857                                                                         /*}}}*/
 858 // VerIterator::TranslatedDescription - Return the a DescIter for locale/*{{{*/
 859 // ---------------------------------------------------------------------
 860 /* return a DescIter for the current locale or the default if none is
 861  * found
 862  */
 863 pkgCache::DescIterator pkgCache::VerIterator::TranslatedDescription() const
 864 {
 865    std::vector<string> const lang = APT::Configuration::getLanguages();
 866    for (std::vector<string>::const_iterator l = lang.begin();
 867         l != lang.end(); l++)
 868    {
 869       pkgCache::DescIterator DescDefault = DescriptionList();
 870       pkgCache::DescIterator Desc = DescDefault;
 871
 872       for (; Desc.end() == false; Desc++)
 873          if (*l == Desc.LanguageCode())
 874             break;
 875       if (Desc.end() == true)
 876          Desc = DescDefault;
 877       return Desc;
 878    }
 879
 880    return DescriptionList();
 881 };
 882
 883                                                                         /*}}}*/