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 management. 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<config.h>
  24
  25 #include <apt-pkg/pkgcache.h>
  26 #include <apt-pkg/policy.h>
  27 #include <apt-pkg/version.h>
  28 #include <apt-pkg/error.h>
  29 #include <apt-pkg/strutl.h>
  30 #include <apt-pkg/configuration.h>
  31 #include <apt-pkg/aptconfiguration.h>
  32 #include <apt-pkg/mmap.h>
  33 #include <apt-pkg/macros.h>
  34
  35 #include <stddef.h>
  36 #include <string.h>
  37 #include <ostream>
  38 #include <vector>
  39 #include <string>
  40 #include <sys/stat.h>
  41
  42 #include <apti18n.h>
  43                                                                         /*}}}*/
  44
  45 using std::string;
  46
  47
  48 // Cache::Header::Header - Constructor                                  /*{{{*/
  49 // ---------------------------------------------------------------------
  50 /* Simply initialize the header */
  51 pkgCache::Header::Header()
  52 {
  53    Signature = 0x98FE76DC;
  54
  55    /* Whenever the structures change the major version should be bumped,
  56       whenever the generator changes the minor version should be bumped. */
  57    MajorVersion = 10;
  58    MinorVersion = 0;
  59    Dirty = false;
  60
  61    HeaderSz = sizeof(pkgCache::Header);
  62    GroupSz = sizeof(pkgCache::Group);
  63    PackageSz = sizeof(pkgCache::Package);
  64    PackageFileSz = sizeof(pkgCache::PackageFile);
  65    VersionSz = sizeof(pkgCache::Version);
  66    DescriptionSz = sizeof(pkgCache::Description);
  67    DependencySz = sizeof(pkgCache::Dependency);
  68    ProvidesSz = sizeof(pkgCache::Provides);
  69    VerFileSz = sizeof(pkgCache::VerFile);
  70    DescFileSz = sizeof(pkgCache::DescFile);
  71
  72    GroupCount = 0;
  73    PackageCount = 0;
  74    VersionCount = 0;
  75    DescriptionCount = 0;
  76    DependsCount = 0;
  77    PackageFileCount = 0;
  78    VerFileCount = 0;
  79    DescFileCount = 0;
  80    ProvidesCount = 0;
  81    MaxVerFileSize = 0;
  82    MaxDescFileSize = 0;
  83
  84    FileList = 0;
  85    VerSysName = 0;
  86    Architecture = 0;
  87    Architectures = 0;
  88    HashTableSize = _config->FindI("APT::Cache-HashTableSize", 10 * 1048);
  89    memset(Pools,0,sizeof(Pools));
  90
  91    CacheFileSize = 0;
  92 }
  93                                                                         /*}}}*/
  94 // Cache::Header::CheckSizes - Check if the two headers have same *sz   /*{{{*/
  95 // ---------------------------------------------------------------------
  96 /* */
  97 bool pkgCache::Header::CheckSizes(Header &Against) const
  98 {
  99    if (HeaderSz == Against.HeaderSz &&
 100        GroupSz == Against.GroupSz &&
 101        PackageSz == Against.PackageSz &&
 102        PackageFileSz == Against.PackageFileSz &&
 103        VersionSz == Against.VersionSz &&
 104        DescriptionSz == Against.DescriptionSz &&
 105        DependencySz == Against.DependencySz &&
 106        VerFileSz == Against.VerFileSz &&
 107        DescFileSz == Against.DescFileSz &&
 108        ProvidesSz == Against.ProvidesSz)
 109       return true;
 110    return false;
 111 }
 112                                                                         /*}}}*/
 113
 114 // Cache::pkgCache - Constructor                                        /*{{{*/
 115 // ---------------------------------------------------------------------
 116 /* */
 117 pkgCache::pkgCache(MMap *Map, bool DoMap) : Map(*Map)
 118 {
 119    // call getArchitectures() with cached=false to ensure that the
 120    // architectures cache is re-evaulated. this is needed in cases
 121    // when the APT::Architecture field changes between two cache creations
 122    MultiArchEnabled = APT::Configuration::getArchitectures(false).size() > 1;
 123    if (DoMap == true)
 124       ReMap();
 125 }
 126                                                                         /*}}}*/
 127 // Cache::ReMap - Reopen the cache file                                 /*{{{*/
 128 // ---------------------------------------------------------------------
 129 /* If the file is already closed then this will open it open it. */
 130 bool pkgCache::ReMap(bool const &Errorchecks)
 131 {
 132    // Apply the typecasts.
 133    HeaderP = (Header *)Map.Data();
 134    GrpP = (Group *)Map.Data();
 135    PkgP = (Package *)Map.Data();
 136    VerFileP = (VerFile *)Map.Data();
 137    DescFileP = (DescFile *)Map.Data();
 138    PkgFileP = (PackageFile *)Map.Data();
 139    VerP = (Version *)Map.Data();
 140    DescP = (Description *)Map.Data();
 141    ProvideP = (Provides *)Map.Data();
 142    DepP = (Dependency *)Map.Data();
 143    StrP = (char *)Map.Data();
 144
 145    if (Errorchecks == false)
 146       return true;
 147
 148    if (Map.Size() == 0 || HeaderP == 0)
 149       return _error->Error(_("Empty package cache"));
 150
 151    // Check the header
 152    Header DefHeader;
 153    if (HeaderP->Signature != DefHeader.Signature ||
 154        HeaderP->Dirty == true)
 155       return _error->Error(_("The package cache file is corrupted"));
 156
 157    if (HeaderP->MajorVersion != DefHeader.MajorVersion ||
 158        HeaderP->MinorVersion != DefHeader.MinorVersion ||
 159        HeaderP->CheckSizes(DefHeader) == false)
 160       return _error->Error(_("The package cache file is an incompatible version"));
 161
 162    if (Map.Size() < HeaderP->CacheFileSize)
 163       return _error->Error(_("The package cache file is corrupted, it is too small"));
 164
 165    if (HeaderP->VerSysName == 0 || HeaderP->Architecture == 0 || HeaderP->Architectures == 0)
 166       return _error->Error(_("The package cache file is corrupted"));
 167
 168    // Locate our VS..
 169    if ((VS = pkgVersioningSystem::GetVS(StrP + HeaderP->VerSysName)) == 0)
 170       return _error->Error(_("This APT does not support the versioning system '%s'"),StrP + HeaderP->VerSysName);
 171
 172    // Check the architecture
 173    std::vector<std::string> archs = APT::Configuration::getArchitectures();
 174    std::vector<std::string>::const_iterator a = archs.begin();
 175    std::string list = *a;
 176    for (++a; a != archs.end(); ++a)
 177       list.append(",").append(*a);
 178    if (_config->Find("APT::Architecture") != StrP + HeaderP->Architecture ||
 179          list != StrP + HeaderP->Architectures)
 180       return _error->Error(_("The package cache was built for different architectures: %s vs %s"), StrP + HeaderP->Architectures, list.c_str());
 181
 182    return true;
 183 }
 184                                                                         /*}}}*/
 185 // Cache::Hash - Hash a string                                          /*{{{*/
 186 // ---------------------------------------------------------------------
 187 /* This is used to generate the hash entries for the HashTable. With my
 188    package list from bo this function gets 94% table usage on a 512 item
 189    table (480 used items) */
 190 map_id_t pkgCache::sHash(const string &Str) const
 191 {
 192    unsigned long Hash = 0;
 193    for (string::const_iterator I = Str.begin(); I != Str.end(); ++I)
 194       Hash = 41 * Hash + tolower_ascii(*I);
 195    return Hash % HeaderP->HashTableSize;
 196 }
 197
 198 map_id_t pkgCache::sHash(const char *Str) const
 199 {
 200    unsigned long Hash = tolower_ascii(*Str);
 201    for (const char *I = Str + 1; *I != 0; ++I)
 202       Hash = 41 * Hash + tolower_ascii(*I);
 203    return Hash % HeaderP->HashTableSize;
 204 }
 205                                                                         /*}}}*/
 206 // Cache::SingleArchFindPkg - Locate a package by name                  /*{{{*/
 207 // ---------------------------------------------------------------------
 208 /* Returns 0 on error, pointer to the package otherwise
 209    The multiArch enabled methods will fallback to this one as it is (a bit)
 210    faster for single arch environments and realworld is mostly singlearch… */
 211 pkgCache::PkgIterator pkgCache::SingleArchFindPkg(const string &Name)
 212 {
 213    // Look at the hash bucket
 214    Package *Pkg = PkgP + HeaderP->PkgHashTable()[Hash(Name)];
 215    for (; Pkg != PkgP; Pkg = PkgP + Pkg->Next)
 216    {
 217       int const cmp = strcmp(Name.c_str(), StrP + (GrpP + Pkg->Group)->Name);
 218       if (cmp == 0)
 219          return PkgIterator(*this, Pkg);
 220       else if (cmp < 0)
 221          break;
 222    }
 223    return PkgIterator(*this,0);
 224 }
 225                                                                         /*}}}*/
 226 // Cache::FindPkg - Locate a package by name                            /*{{{*/
 227 // ---------------------------------------------------------------------
 228 /* Returns 0 on error, pointer to the package otherwise */
 229 pkgCache::PkgIterator pkgCache::FindPkg(const string &Name) {
 230         size_t const found = Name.find(':');
 231         if (found == string::npos)
 232         {
 233                 if (MultiArchCache() == false)
 234                         return SingleArchFindPkg(Name);
 235                 else
 236                         return FindPkg(Name, "native");
 237         }
 238         string const Arch = Name.substr(found+1);
 239         /* Beware: This is specialcased to handle pkg:any in dependencies as
 240            these are linked to virtual pkg:any named packages with all archs.
 241            If you want any arch from a given pkg, use FindPkg(pkg,arch) */
 242         if (Arch == "any")
 243                 return FindPkg(Name, "any");
 244         return FindPkg(Name.substr(0, found), Arch);
 245 }
 246                                                                         /*}}}*/
 247 // Cache::FindPkg - Locate a package by name                            /*{{{*/
 248 // ---------------------------------------------------------------------
 249 /* Returns 0 on error, pointer to the package otherwise */
 250 pkgCache::PkgIterator pkgCache::FindPkg(const string &Name, string const &Arch) {
 251         if (MultiArchCache() == false && Arch != "none") {
 252                 if (Arch == "native" || Arch == "all" || Arch == "any" ||
 253                     Arch == NativeArch())
 254                         return SingleArchFindPkg(Name);
 255                 else
 256                         return PkgIterator(*this,0);
 257         }
 258         /* We make a detour via the GrpIterator here as
 259            on a multi-arch environment a group is easier to
 260            find than a package (less entries in the buckets) */
 261         pkgCache::GrpIterator Grp = FindGrp(Name);
 262         if (Grp.end() == true)
 263                 return PkgIterator(*this,0);
 264
 265         return Grp.FindPkg(Arch);
 266 }
 267                                                                         /*}}}*/
 268 // Cache::FindGrp - Locate a group by name                              /*{{{*/
 269 // ---------------------------------------------------------------------
 270 /* Returns End-Pointer on error, pointer to the group otherwise */
 271 pkgCache::GrpIterator pkgCache::FindGrp(const string &Name) {
 272         if (unlikely(Name.empty() == true))
 273                 return GrpIterator(*this,0);
 274
 275         // Look at the hash bucket for the group
 276         Group *Grp = GrpP + HeaderP->GrpHashTable()[sHash(Name)];
 277         for (; Grp != GrpP; Grp = GrpP + Grp->Next) {
 278                 int const cmp = strcmp(Name.c_str(), StrP + Grp->Name);
 279                 if (cmp == 0)
 280                         return GrpIterator(*this, Grp);
 281                 else if (cmp < 0)
 282                         break;
 283         }
 284
 285         return GrpIterator(*this,0);
 286 }
 287                                                                         /*}}}*/
 288 // Cache::CompTypeDeb - Return a string describing the compare type     /*{{{*/
 289 // ---------------------------------------------------------------------
 290 /* This returns a string representation of the dependency compare
 291    type in the weird debian style.. */
 292 const char *pkgCache::CompTypeDeb(unsigned char Comp)
 293 {
 294    const char * const Ops[] = {"","<=",">=","<<",">>","=","!="};
 295    if (unlikely((unsigned)(Comp & 0xF) >= sizeof(Ops)/sizeof(Ops[0])))
 296       return "";
 297    return Ops[Comp & 0xF];
 298 }
 299                                                                         /*}}}*/
 300 // Cache::CompType - Return a string describing the compare type        /*{{{*/
 301 // ---------------------------------------------------------------------
 302 /* This returns a string representation of the dependency compare
 303    type */
 304 const char *pkgCache::CompType(unsigned char Comp)
 305 {
 306    const char * const Ops[] = {"","<=",">=","<",">","=","!="};
 307    if (unlikely((unsigned)(Comp & 0xF) >= sizeof(Ops)/sizeof(Ops[0])))
 308       return "";
 309    return Ops[Comp & 0xF];
 310 }
 311                                                                         /*}}}*/
 312 // Cache::DepType - Return a string describing the dep type             /*{{{*/
 313 // ---------------------------------------------------------------------
 314 /* */
 315 const char *pkgCache::DepType(unsigned char Type)
 316 {
 317    const char *Types[] = {"",_("Depends"),_("PreDepends"),_("Suggests"),
 318                           _("Recommends"),_("Conflicts"),_("Replaces"),
 319                           _("Obsoletes"),_("Breaks"), _("Enhances")};
 320    if (Type < sizeof(Types)/sizeof(*Types))
 321       return Types[Type];
 322    return "";
 323 }
 324                                                                         /*}}}*/
 325 // Cache::Priority - Convert a priority value to a string               /*{{{*/
 326 // ---------------------------------------------------------------------
 327 /* */
 328 const char *pkgCache::Priority(unsigned char Prio)
 329 {
 330    const char *Mapping[] = {0,_("important"),_("required"),_("standard"),
 331                             _("optional"),_("extra")};
 332    if (Prio < _count(Mapping))
 333       return Mapping[Prio];
 334    return 0;
 335 }
 336                                                                         /*}}}*/
 337 // GrpIterator::FindPkg - Locate a package by arch                      /*{{{*/
 338 // ---------------------------------------------------------------------
 339 /* Returns an End-Pointer on error, pointer to the package otherwise */
 340 pkgCache::PkgIterator pkgCache::GrpIterator::FindPkg(string Arch) const {
 341         if (unlikely(IsGood() == false || S->FirstPackage == 0))
 342                 return PkgIterator(*Owner, 0);
 343
 344         /* If we accept any package we simply return the "first"
 345            package in this group (the last one added). */
 346         if (Arch == "any")
 347                 return PkgIterator(*Owner, Owner->PkgP + S->FirstPackage);
 348
 349         char const* const myArch = Owner->NativeArch();
 350         /* Most of the time the package for our native architecture is
 351            the one we add at first to the cache, but this would be the
 352            last one we check, so we do it now. */
 353         if (Arch == "native" || Arch == myArch || Arch == "all") {
 354                 pkgCache::Package *Pkg = Owner->PkgP + S->LastPackage;
 355                 if (strcmp(myArch, Owner->StrP + Pkg->Arch) == 0)
 356                         return PkgIterator(*Owner, Pkg);
 357                 Arch = myArch;
 358         }
 359
 360         // Iterate over the list to find the matching arch
 361         for (pkgCache::Package *Pkg = PackageList(); Pkg != Owner->PkgP;
 362              Pkg = Owner->PkgP + Pkg->Next) {
 363                 if (stringcmp(Arch, Owner->StrP + Pkg->Arch) == 0)
 364                         return PkgIterator(*Owner, Pkg);
 365                 if ((Owner->PkgP + S->LastPackage) == Pkg)
 366                         break;
 367         }
 368
 369         return PkgIterator(*Owner, 0);
 370 }
 371                                                                         /*}}}*/
 372 // GrpIterator::FindPreferredPkg - Locate the "best" package            /*{{{*/
 373 // ---------------------------------------------------------------------
 374 /* Returns an End-Pointer on error, pointer to the package otherwise */
 375 pkgCache::PkgIterator pkgCache::GrpIterator::FindPreferredPkg(bool const &PreferNonVirtual) const {
 376         pkgCache::PkgIterator Pkg = FindPkg("native");
 377         if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 378                 return Pkg;
 379
 380         std::vector<std::string> const archs = APT::Configuration::getArchitectures();
 381         for (std::vector<std::string>::const_iterator a = archs.begin();
 382              a != archs.end(); ++a) {
 383                 Pkg = FindPkg(*a);
 384                 if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 385                         return Pkg;
 386         }
 387         // packages without an architecture
 388         Pkg = FindPkg("none");
 389         if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
 390                 return Pkg;
 391
 392         if (PreferNonVirtual == true)
 393                 return FindPreferredPkg(false);
 394         return PkgIterator(*Owner, 0);
 395 }
 396                                                                         /*}}}*/
 397 // GrpIterator::NextPkg - Locate the next package in the group          /*{{{*/
 398 // ---------------------------------------------------------------------
 399 /* Returns an End-Pointer on error, pointer to the package otherwise.
 400    We can't simply ++ to the next as the next package of the last will
 401    be from a different group (with the same hash value) */
 402 pkgCache::PkgIterator pkgCache::GrpIterator::NextPkg(pkgCache::PkgIterator const &LastPkg) const {
 403         if (unlikely(IsGood() == false || S->FirstPackage == 0 ||
 404             LastPkg.end() == true))
 405                 return PkgIterator(*Owner, 0);
 406
 407         if (S->LastPackage == LastPkg.Index())
 408                 return PkgIterator(*Owner, 0);
 409
 410         return PkgIterator(*Owner, Owner->PkgP + LastPkg->Next);
 411 }
 412                                                                         /*}}}*/
 413 // GrpIterator::operator ++ - Postfix incr                              /*{{{*/
 414 // ---------------------------------------------------------------------
 415 /* This will advance to the next logical group in the hash table. */
 416 void pkgCache::GrpIterator::operator ++(int)
 417 {
 418    // Follow the current links
 419    if (S != Owner->GrpP)
 420       S = Owner->GrpP + S->Next;
 421
 422    // Follow the hash table
 423    while (S == Owner->GrpP && (HashIndex+1) < (signed)Owner->HeaderP->HashTableSize)
 424    {
 425       HashIndex++;
 426       S = Owner->GrpP + Owner->HeaderP->GrpHashTable()[HashIndex];
 427    }
 428 }
 429                                                                         /*}}}*/
 430 // PkgIterator::operator ++ - Postfix incr                              /*{{{*/
 431 // ---------------------------------------------------------------------
 432 /* This will advance to the next logical package in the hash table. */
 433 void pkgCache::PkgIterator::operator ++(int)
 434 {
 435    // Follow the current links
 436    if (S != Owner->PkgP)
 437       S = Owner->PkgP + S->Next;
 438
 439    // Follow the hash table
 440    while (S == Owner->PkgP && (HashIndex+1) < (signed)Owner->HeaderP->HashTableSize)
 441    {
 442       HashIndex++;
 443       S = Owner->PkgP + Owner->HeaderP->PkgHashTable()[HashIndex];
 444    }
 445 }
 446                                                                         /*}}}*/
 447 // PkgIterator::State - Check the State of the package                  /*{{{*/
 448 // ---------------------------------------------------------------------
 449 /* By this we mean if it is either cleanly installed or cleanly removed. */
 450 pkgCache::PkgIterator::OkState pkgCache::PkgIterator::State() const
 451 {
 452    if (S->InstState == pkgCache::State::ReInstReq ||
 453        S->InstState == pkgCache::State::HoldReInstReq)
 454       return NeedsUnpack;
 455
 456    if (S->CurrentState == pkgCache::State::UnPacked ||
 457        S->CurrentState == pkgCache::State::HalfConfigured)
 458       // we leave triggers alone complettely. dpkg deals with
 459       // them in a hard-to-predict manner and if they get
 460       // resolved by dpkg before apt run dpkg --configure on
 461       // the TriggersPending package dpkg returns a error
 462       //Pkg->CurrentState == pkgCache::State::TriggersAwaited
 463       //Pkg->CurrentState == pkgCache::State::TriggersPending)
 464       return NeedsConfigure;
 465
 466    if (S->CurrentState == pkgCache::State::HalfInstalled ||
 467        S->InstState != pkgCache::State::Ok)
 468       return NeedsUnpack;
 469
 470    return NeedsNothing;
 471 }
 472                                                                         /*}}}*/
 473 // PkgIterator::CandVersion - Returns the candidate version string      /*{{{*/
 474 // ---------------------------------------------------------------------
 475 /* Return string representing of the candidate version. */
 476 const char *
 477 pkgCache::PkgIterator::CandVersion() const
 478 {
 479   //TargetVer is empty, so don't use it.
 480   VerIterator version = pkgPolicy(Owner).GetCandidateVer(*this);
 481   if (version.IsGood())
 482     return version.VerStr();
 483   return 0;
 484 }
 485                                                                         /*}}}*/
 486 // PkgIterator::CurVersion - Returns the current version string         /*{{{*/
 487 // ---------------------------------------------------------------------
 488 /* Return string representing of the current version. */
 489 const char *
 490 pkgCache::PkgIterator::CurVersion() const
 491 {
 492   VerIterator version = CurrentVer();
 493   if (version.IsGood())
 494     return CurrentVer().VerStr();
 495   return 0;
 496 }
 497                                                                         /*}}}*/
 498 // ostream operator to handle string representation of a package        /*{{{*/
 499 // ---------------------------------------------------------------------
 500 /* Output name < cur.rent.version -> candid.ate.version | new.est.version > (section)
 501    Note that the characters <|>() are all literal above. Versions will be omitted
 502    if they provide no new information (e.g. there is no newer version than candidate)
 503    If no version and/or section can be found "none" is used. */
 504 std::ostream&
 505 operator<<(std::ostream& out, pkgCache::PkgIterator Pkg)
 506 {
 507    if (Pkg.end() == true)
 508       return out << "invalid package";
 509
 510    string current = string(Pkg.CurVersion() == 0 ? "none" : Pkg.CurVersion());
 511    string candidate = string(Pkg.CandVersion() == 0 ? "none" : Pkg.CandVersion());
 512    string newest = string(Pkg.VersionList().end() ? "none" : Pkg.VersionList().VerStr());
 513
 514    out << Pkg.Name() << " [ " << Pkg.Arch() << " ] < " << current;
 515    if (current != candidate)
 516       out << " -> " << candidate;
 517    if ( newest != "none" && candidate != newest)
 518       out << " | " << newest;
 519    if (Pkg->VersionList == 0)
 520       out << " > ( none )";
 521    else
 522       out << " > ( " << string(Pkg.VersionList().Section()==0?"unknown":Pkg.VersionList().Section()) << " )";
 523    return out;
 524 }
 525                                                                         /*}}}*/
 526 // PkgIterator::FullName - Returns Name and (maybe) Architecture        /*{{{*/
 527 // ---------------------------------------------------------------------
 528 /* Returns a name:arch string */
 529 std::string pkgCache::PkgIterator::FullName(bool const &Pretty) const
 530 {
 531    string fullname = Name();
 532    if (Pretty == false ||
 533        (strcmp(Arch(), "all") != 0 &&
 534         strcmp(Owner->NativeArch(), Arch()) != 0))
 535       return fullname.append(":").append(Arch());
 536    return fullname;
 537 }
 538                                                                         /*}}}*/
 539 // DepIterator::IsCritical - Returns true if the dep is important       /*{{{*/
 540 // ---------------------------------------------------------------------
 541 /* Currently critical deps are defined as depends, predepends and
 542    conflicts (including dpkg's Breaks fields). */
 543 bool pkgCache::DepIterator::IsCritical() const
 544 {
 545    if (IsNegative() == true ||
 546        S->Type == pkgCache::Dep::Depends ||
 547        S->Type == pkgCache::Dep::PreDepends)
 548       return true;
 549    return false;
 550 }
 551                                                                         /*}}}*/
 552 // DepIterator::IsNegative - Returns true if the dep is a negative one  /*{{{*/
 553 // ---------------------------------------------------------------------
 554 /* Some dependencies are positive like Depends and Recommends, others
 555    are negative like Conflicts which can and should be handled differently */
 556 bool pkgCache::DepIterator::IsNegative() const
 557 {
 558    return S->Type == Dep::DpkgBreaks ||
 559           S->Type == Dep::Conflicts ||
 560           S->Type == Dep::Obsoletes;
 561 }
 562                                                                         /*}}}*/
 563 // DepIterator::SmartTargetPkg - Resolve dep target pointers w/provides /*{{{*/
 564 // ---------------------------------------------------------------------
 565 /* This intellegently looks at dep target packages and tries to figure
 566    out which package should be used. This is needed to nicely handle
 567    provide mapping. If the target package has no other providing packages
 568    then it returned. Otherwise the providing list is looked at to
 569    see if there is one one unique providing package if so it is returned.
 570    Otherwise true is returned and the target package is set. The return
 571    result indicates whether the node should be expandable
 572
 573    In Conjunction with the DepCache the value of Result may not be
 574    super-good since the policy may have made it uninstallable. Using
 575    AllTargets is better in this case. */
 576 bool pkgCache::DepIterator::SmartTargetPkg(PkgIterator &Result) const
 577 {
 578    Result = TargetPkg();
 579
 580    // No provides at all
 581    if (Result->ProvidesList == 0)
 582       return false;
 583
 584    // There is the Base package and the providing ones which is at least 2
 585    if (Result->VersionList != 0)
 586       return true;
 587
 588    /* We have to skip over indirect provisions of the package that
 589       owns the dependency. For instance, if libc5-dev depends on the
 590       virtual package libc-dev which is provided by libc5-dev and libc6-dev
 591       we must ignore libc5-dev when considering the provides list. */
 592    PrvIterator PStart = Result.ProvidesList();
 593    for (; PStart.end() != true && PStart.OwnerPkg() == ParentPkg(); ++PStart);
 594
 595    // Nothing but indirect self provides
 596    if (PStart.end() == true)
 597       return false;
 598
 599    // Check for single packages in the provides list
 600    PrvIterator P = PStart;
 601    for (; P.end() != true; ++P)
 602    {
 603       // Skip over self provides
 604       if (P.OwnerPkg() == ParentPkg())
 605          continue;
 606       if (PStart.OwnerPkg() != P.OwnerPkg())
 607          break;
 608    }
 609
 610    Result = PStart.OwnerPkg();
 611
 612    // Check for non dups
 613    if (P.end() != true)
 614       return true;
 615
 616    return false;
 617 }
 618                                                                         /*}}}*/
 619 // DepIterator::AllTargets - Returns the set of all possible targets    /*{{{*/
 620 // ---------------------------------------------------------------------
 621 /* This is a more useful version of TargetPkg() that follows versioned
 622    provides. It includes every possible package-version that could satisfy
 623    the dependency. The last item in the list has a 0. The resulting pointer
 624    must be delete [] 'd */
 625 pkgCache::Version **pkgCache::DepIterator::AllTargets() const
 626 {
 627    Version **Res = 0;
 628    unsigned long Size =0;
 629    while (1)
 630    {
 631       Version **End = Res;
 632       PkgIterator DPkg = TargetPkg();
 633
 634       // Walk along the actual package providing versions
 635       for (VerIterator I = DPkg.VersionList(); I.end() == false; ++I)
 636       {
 637          if (IsIgnorable(I.ParentPkg()) == true)
 638             continue;
 639          if (IsSatisfied(I) == false)
 640             continue;
 641
 642          Size++;
 643          if (Res != 0)
 644             *End++ = I;
 645       }
 646
 647       // Follow all provides
 648       for (PrvIterator I = DPkg.ProvidesList(); I.end() == false; ++I)
 649       {
 650          if (IsIgnorable(I) == true)
 651             continue;
 652          if (IsSatisfied(I) == false)
 653             continue;
 654
 655          Size++;
 656          if (Res != 0)
 657             *End++ = I.OwnerVer();
 658       }
 659
 660       // Do it again and write it into the array
 661       if (Res == 0)
 662       {
 663          Res = new Version *[Size+1];
 664          Size = 0;
 665       }
 666       else
 667       {
 668          *End = 0;
 669          break;
 670       }
 671    }
 672
 673    return Res;
 674 }
 675                                                                         /*}}}*/
 676 // DepIterator::GlobOr - Compute an OR group                            /*{{{*/
 677 // ---------------------------------------------------------------------
 678 /* This Takes an iterator, iterates past the current dependency grouping
 679    and returns Start and End so that so End is the final element
 680    in the group, if End == Start then D is End++ and End is the
 681    dependency D was pointing to. Use in loops to iterate sensibly. */
 682 void pkgCache::DepIterator::GlobOr(DepIterator &Start,DepIterator &End)
 683 {
 684    // Compute a single dependency element (glob or)
 685    Start = *this;
 686    End = *this;
 687    for (bool LastOR = true; end() == false && LastOR == true;)
 688    {
 689       LastOR = (S->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
 690       (*this)++;
 691       if (LastOR == true)
 692          End = (*this);
 693    }
 694 }
 695                                                                         /*}}}*/
 696 // DepIterator::IsIgnorable - should this packag/providr be ignored?    /*{{{*/
 697 // ---------------------------------------------------------------------
 698 /* Deps like self-conflicts should be ignored as well as implicit conflicts
 699    on virtual packages. */
 700 bool pkgCache::DepIterator::IsIgnorable(PkgIterator const &/*Pkg*/) const
 701 {
 702    if (IsNegative() == false)
 703       return false;
 704
 705    pkgCache::PkgIterator PP = ParentPkg();
 706    pkgCache::PkgIterator PT = TargetPkg();
 707    if (PP->Group != PT->Group)
 708       return false;
 709    // self-conflict
 710    if (PP == PT)
 711       return true;
 712    pkgCache::VerIterator PV = ParentVer();
 713    // ignore group-conflict on a M-A:same package - but not our implicit dependencies
 714    // so that we can have M-A:same packages conflicting with their own real name
 715    if ((PV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
 716    {
 717       // Replaces: ${self}:other ( << ${binary:Version})
 718       if (S->Type == pkgCache::Dep::Replaces && S->CompareOp == pkgCache::Dep::Less && strcmp(PV.VerStr(), TargetVer()) == 0)
 719          return false;
 720       // Breaks: ${self}:other (!= ${binary:Version})
 721       if (S->Type == pkgCache::Dep::DpkgBreaks && S->CompareOp == pkgCache::Dep::NotEquals && strcmp(PV.VerStr(), TargetVer()) == 0)
 722          return false;
 723       return true;
 724    }
 725
 726    return false;
 727 }
 728 bool pkgCache::DepIterator::IsIgnorable(PrvIterator const &Prv) const
 729 {
 730    if (IsNegative() == false)
 731       return false;
 732
 733    PkgIterator const Pkg = ParentPkg();
 734    /* Provides may never be applied against the same package (or group)
 735       if it is a conflicts. See the comment above. */
 736    if (Prv.OwnerPkg()->Group == Pkg->Group)
 737       return true;
 738    // Implicit group-conflicts should not be applied on providers of other groups
 739    if (Pkg->Group == TargetPkg()->Group && Prv.OwnerPkg()->Group != Pkg->Group)
 740       return true;
 741
 742    return false;
 743 }
 744                                                                         /*}}}*/
 745 // DepIterator::IsMultiArchImplicit - added by the cache generation     /*{{{*/
 746 // ---------------------------------------------------------------------
 747 /* MultiArch can be translated to SingleArch for an resolver and we did so,
 748    by adding dependencies to help the resolver understand the problem, but
 749    sometimes it is needed to identify these to ignore them… */
 750 bool pkgCache::DepIterator::IsMultiArchImplicit() const
 751 {
 752    if (ParentPkg()->Arch != TargetPkg()->Arch &&
 753        (S->Type == pkgCache::Dep::Replaces ||
 754         S->Type == pkgCache::Dep::DpkgBreaks ||
 755         S->Type == pkgCache::Dep::Conflicts))
 756       return true;
 757    return false;
 758 }
 759                                                                         /*}}}*/
 760 // DepIterator::IsSatisfied - check if a version satisfied the dependency /*{{{*/
 761 bool pkgCache::DepIterator::IsSatisfied(VerIterator const &Ver) const
 762 {
 763    return Owner->VS->CheckDep(Ver.VerStr(),S->CompareOp,TargetVer());
 764 }
 765 bool pkgCache::DepIterator::IsSatisfied(PrvIterator const &Prv) const
 766 {
 767    return Owner->VS->CheckDep(Prv.ProvideVersion(),S->CompareOp,TargetVer());
 768 }
 769                                                                         /*}}}*/
 770 // ostream operator to handle string representation of a dependecy      /*{{{*/
 771 // ---------------------------------------------------------------------
 772 /* */
 773 std::ostream& operator<<(std::ostream& out, pkgCache::DepIterator D)
 774 {
 775    if (D.end() == true)
 776       return out << "invalid dependency";
 777
 778    pkgCache::PkgIterator P = D.ParentPkg();
 779    pkgCache::PkgIterator T = D.TargetPkg();
 780
 781    out << (P.end() ? "invalid pkg" : P.FullName(false)) << " " << D.DepType()
 782         << " on ";
 783    if (T.end() == true)
 784       out << "invalid pkg";
 785    else
 786       out << T;
 787
 788    if (D->Version != 0)
 789       out << " (" << D.CompType() << " " << D.TargetVer() << ")";
 790
 791    return out;
 792 }
 793                                                                         /*}}}*/
 794 // VerIterator::CompareVer - Fast version compare for same pkgs         /*{{{*/
 795 // ---------------------------------------------------------------------
 796 /* This just looks over the version list to see if B is listed before A. In
 797    most cases this will return in under 4 checks, ver lists are short. */
 798 int pkgCache::VerIterator::CompareVer(const VerIterator &B) const
 799 {
 800    // Check if they are equal
 801    if (*this == B)
 802       return 0;
 803    if (end() == true)
 804       return -1;
 805    if (B.end() == true)
 806       return 1;
 807
 808    /* Start at A and look for B. If B is found then A > B otherwise
 809       B was before A so A < B */
 810    VerIterator I = *this;
 811    for (;I.end() == false; ++I)
 812       if (I == B)
 813          return 1;
 814    return -1;
 815 }
 816                                                                         /*}}}*/
 817 // VerIterator::Downloadable - Checks if the version is downloadable    /*{{{*/
 818 // ---------------------------------------------------------------------
 819 /* */
 820 APT_PURE bool pkgCache::VerIterator::Downloadable() const
 821 {
 822    VerFileIterator Files = FileList();
 823    for (; Files.end() == false; ++Files)
 824       if ((Files.File()->Flags & pkgCache::Flag::NotSource) != pkgCache::Flag::NotSource)
 825          return true;
 826    return false;
 827 }
 828                                                                         /*}}}*/
 829 // VerIterator::Automatic - Check if this version is 'automatic'        /*{{{*/
 830 // ---------------------------------------------------------------------
 831 /* This checks to see if any of the versions files are not NotAutomatic.
 832    True if this version is selectable for automatic installation. */
 833 APT_PURE bool pkgCache::VerIterator::Automatic() const
 834 {
 835    VerFileIterator Files = FileList();
 836    for (; Files.end() == false; ++Files)
 837       // Do not check ButAutomaticUpgrades here as it is kind of automatic…
 838       if ((Files.File()->Flags & pkgCache::Flag::NotAutomatic) != pkgCache::Flag::NotAutomatic)
 839          return true;
 840    return false;
 841 }
 842                                                                         /*}}}*/
 843 // VerIterator::NewestFile - Return the newest file version relation    /*{{{*/
 844 // ---------------------------------------------------------------------
 845 /* This looks at the version numbers associated with all of the sources
 846    this version is in and returns the highest.*/
 847 pkgCache::VerFileIterator pkgCache::VerIterator::NewestFile() const
 848 {
 849    VerFileIterator Files = FileList();
 850    VerFileIterator Highest = Files;
 851    for (; Files.end() == false; ++Files)
 852    {
 853       if (Owner->VS->CmpReleaseVer(Files.File().Version(),Highest.File().Version()) > 0)
 854          Highest = Files;
 855    }
 856
 857    return Highest;
 858 }
 859                                                                         /*}}}*/
 860 // VerIterator::RelStr - Release description string                     /*{{{*/
 861 // ---------------------------------------------------------------------
 862 /* This describes the version from a release-centric manner. The output is a
 863    list of Label:Version/Archive */
 864 string pkgCache::VerIterator::RelStr() const
 865 {
 866    bool First = true;
 867    string Res;
 868    for (pkgCache::VerFileIterator I = this->FileList(); I.end() == false; ++I)
 869    {
 870       // Do not print 'not source' entries'
 871       pkgCache::PkgFileIterator File = I.File();
 872       if ((File->Flags & pkgCache::Flag::NotSource) == pkgCache::Flag::NotSource)
 873          continue;
 874
 875       // See if we have already printed this out..
 876       bool Seen = false;
 877       for (pkgCache::VerFileIterator J = this->FileList(); I != J; ++J)
 878       {
 879          pkgCache::PkgFileIterator File2 = J.File();
 880          if (File2->Label == 0 || File->Label == 0)
 881             continue;
 882
 883          if (strcmp(File.Label(),File2.Label()) != 0)
 884             continue;
 885
 886          if (File2->Version == File->Version)
 887          {
 888             Seen = true;
 889             break;
 890          }
 891          if (File2->Version == 0 || File->Version == 0)
 892             break;
 893          if (strcmp(File.Version(),File2.Version()) == 0)
 894             Seen = true;
 895       }
 896
 897       if (Seen == true)
 898          continue;
 899
 900       if (First == false)
 901          Res += ", ";
 902       else
 903          First = false;
 904
 905       if (File->Label != 0)
 906          Res = Res + File.Label() + ':';
 907
 908       if (File->Archive != 0)
 909       {
 910          if (File->Version == 0)
 911             Res += File.Archive();
 912          else
 913             Res = Res + File.Version() + '/' +  File.Archive();
 914       }
 915       else
 916       {
 917          // No release file, print the host name that this came from
 918          if (File->Site == 0 || File.Site()[0] == 0)
 919             Res += "localhost";
 920          else
 921             Res += File.Site();
 922       }
 923    }
 924    if (S->ParentPkg != 0)
 925       Res.append(" [").append(Arch()).append("]");
 926    return Res;
 927 }
 928                                                                         /*}}}*/
 929 // VerIterator::MultiArchType - string representing MultiArch flag      /*{{{*/
 930 const char * pkgCache::VerIterator::MultiArchType() const
 931 {
 932    if ((S->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
 933       return "same";
 934    else if ((S->MultiArch & pkgCache::Version::Foreign) == pkgCache::Version::Foreign)
 935       return "foreign";
 936    else if ((S->MultiArch & pkgCache::Version::Allowed) == pkgCache::Version::Allowed)
 937       return "allowed";
 938    return "none";
 939 }
 940                                                                         /*}}}*/
 941 // PkgFileIterator::IsOk - Checks if the cache is in sync with the file /*{{{*/
 942 // ---------------------------------------------------------------------
 943 /* This stats the file and compares its stats with the ones that were
 944    stored during generation. Date checks should probably also be
 945    included here. */
 946 bool pkgCache::PkgFileIterator::IsOk()
 947 {
 948    struct stat Buf;
 949    if (stat(FileName(),&Buf) != 0)
 950       return false;
 951
 952    if (Buf.st_size != (signed)S->Size || Buf.st_mtime != S->mtime)
 953       return false;
 954
 955    return true;
 956 }
 957                                                                         /*}}}*/
 958 // PkgFileIterator::RelStr - Return the release string                  /*{{{*/
 959 // ---------------------------------------------------------------------
 960 /* */
 961 string pkgCache::PkgFileIterator::RelStr()
 962 {
 963    string Res;
 964    if (Version() != 0)
 965       Res = Res + (Res.empty() == true?"v=":",v=") + Version();
 966    if (Origin() != 0)
 967       Res = Res + (Res.empty() == true?"o=":",o=")  + Origin();
 968    if (Archive() != 0)
 969       Res = Res + (Res.empty() == true?"a=":",a=")  + Archive();
 970    if (Codename() != 0)
 971       Res = Res + (Res.empty() == true?"n=":",n=")  + Codename();
 972    if (Label() != 0)
 973       Res = Res + (Res.empty() == true?"l=":",l=")  + Label();
 974    if (Component() != 0)
 975       Res = Res + (Res.empty() == true?"c=":",c=")  + Component();
 976    if (Architecture() != 0)
 977       Res = Res + (Res.empty() == true?"b=":",b=")  + Architecture();
 978    return Res;
 979 }
 980                                                                         /*}}}*/
 981 // VerIterator::TranslatedDescription - Return the a DescIter for locale/*{{{*/
 982 // ---------------------------------------------------------------------
 983 /* return a DescIter for the current locale or the default if none is
 984  * found
 985  */
 986 pkgCache::DescIterator pkgCache::VerIterator::TranslatedDescription() const
 987 {
 988    std::vector<string> const lang = APT::Configuration::getLanguages();
 989    for (std::vector<string>::const_iterator l = lang.begin();
 990         l != lang.end(); ++l)
 991    {
 992       pkgCache::DescIterator Desc = DescriptionList();
 993       for (; Desc.end() == false; ++Desc)
 994          if (*l == Desc.LanguageCode())
 995             break;
 996       if (Desc.end() == true)
 997       {
 998          if (*l == "en")
 999          {
1000             Desc = DescriptionList();
1001             for (; Desc.end() == false; ++Desc)
1002                if (strcmp(Desc.LanguageCode(), "") == 0)
1003                   break;
1004             if (Desc.end() == true)
1005                continue;
1006          }
1007          else
1008             continue;
1009       }
1010       return Desc;
1011    }
1012    for (pkgCache::DescIterator Desc = DescriptionList();
1013         Desc.end() == false; ++Desc)
1014       if (strcmp(Desc.LanguageCode(), "") == 0)
1015          return Desc;
1016    return DescriptionList();
1017 }
1018
1019                                                                         /*}}}*/
1020 // PrvIterator::IsMultiArchImplicit - added by the cache generation     /*{{{*/
1021 // ---------------------------------------------------------------------
1022 /* MultiArch can be translated to SingleArch for an resolver and we did so,
1023    by adding provides to help the resolver understand the problem, but
1024    sometimes it is needed to identify these to ignore them… */
1025 bool pkgCache::PrvIterator::IsMultiArchImplicit() const
1026 {
1027    pkgCache::PkgIterator const Owner = OwnerPkg();
1028    pkgCache::PkgIterator const Parent = ParentPkg();
1029    if (strcmp(Owner.Arch(), Parent.Arch()) != 0 || Owner.Group()->Name == Parent.Group()->Name)
1030       return true;
1031    return false;
1032 }
1033                                                                         /*}}}*/
1034 APT_DEPRECATED APT_PURE const char * pkgCache::PkgIterator::Section() const {/*{{{*/
1035    if (S->VersionList == 0)
1036       return 0;
1037    return VersionList().Section();
1038 }
1039                                                                         /*}}}*/