apt-pkg/cacheiterators.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 /* ######################################################################
   4
   5    Cache Iterators - Iterators for navigating the cache structure
   6
   7    The iterators all provides ++,==,!=,->,* and end for their type.
   8    The end function can be used to tell if the list has been fully
   9    traversed.
  10
  11    Unlike STL iterators these contain helper functions to access the data
  12    that is being iterated over. This is because the data structures can't
  13    be formed in a manner that is intuitive to use and also mmapable.
  14
  15    For each variable in the target structure that would need a translation
  16    to be accessed correctly a translating function of the same name is
  17    present in the iterator. If applicable the translating function will
  18    return an iterator.
  19
  20    The DepIterator can iterate over two lists, a list of 'version depends'
  21    or a list of 'package reverse depends'. The type is determined by the
  22    structure passed to the constructor, which should be the structure
  23    that has the depends pointer as a member. The provide iterator has the
  24    same system.
  25
  26    This header is not user includable, please use apt-pkg/pkgcache.h
  27
  28    ##################################################################### */
  29                                                                         /*}}}*/
  30 #ifndef PKGLIB_CACHEITERATORS_H
  31 #define PKGLIB_CACHEITERATORS_H
  32 #include<iterator>
  33
  34 #include<string.h>
  35
  36 // abstract Iterator template                                           /*{{{*/
  37 /* This template provides the very basic iterator methods we
  38    need to have for doing some walk-over-the-cache magic */
  39 template<typename Str, typename Itr> class pkgCache::Iterator :
  40                         public std::iterator<std::forward_iterator_tag, Str> {
  41         protected:
  42         Str *S;
  43         pkgCache *Owner;
  44
  45         /** \brief Returns the Pointer for this struct in the owner
  46          *  The implementation of this method should be pretty short
  47          *  as it will only return the Pointer into the mmap stored
  48          *  in the owner but the name of this pointer is different for
  49          *  each structure and we want to abstract here at least for the
  50          *  basic methods from the actual structure.
  51          *  \return Pointer to the first structure of this type
  52          */
  53         virtual Str* OwnerPointer() const = 0;
  54
  55         public:
  56         // Iteration
  57         virtual void operator ++(int) = 0;
  58         virtual void operator ++() = 0; // Should be {operator ++(0);}
  59         inline bool end() const {return Owner == 0 || S == OwnerPointer();}
  60
  61         // Comparison
  62         inline bool operator ==(const Itr &B) const {return S == B.S;}
  63         inline bool operator !=(const Itr &B) const {return S != B.S;}
  64
  65         // Accessors
  66         inline Str *operator ->() {return S;}
  67         inline Str const *operator ->() const {return S;}
  68         inline operator Str *() {return S == OwnerPointer() ? 0 : S;}
  69         inline operator Str const *() const {return S == OwnerPointer() ? 0 : S;}
  70         inline Str &operator *() {return *S;}
  71         inline Str const &operator *() const {return *S;}
  72         inline pkgCache *Cache() const {return Owner;}
  73
  74         // Mixed stuff
  75         inline void operator =(const Itr &B) {S = B.S; Owner = B.Owner;}
  76         inline bool IsGood() const { return S && Owner && ! end();}
  77         inline unsigned long Index() const {return S - OwnerPointer();}
  78
  79         void ReMap(void const * const oldMap, void const * const newMap) {
  80                 if (Owner == 0 || S == 0)
  81                         return;
  82                 S += (Str*)(newMap) - (Str*)(oldMap);
  83         }
  84
  85         // Constructors - look out for the variable assigning
  86         inline Iterator() : S(0), Owner(0) {}
  87         inline Iterator(pkgCache &Owner,Str *T = 0) : S(T), Owner(&Owner) {}
  88 };
  89                                                                         /*}}}*/
  90 // Group Iterator                                                       /*{{{*/
  91 /* Packages with the same name are collected in a Group so someone only
  92    interest in package names can iterate easily over the names, so the
  93    different architectures can be treated as of the "same" package
  94    (apt internally treat them as totally different packages) */
  95 class pkgCache::GrpIterator: public Iterator<Group, GrpIterator> {
  96         long HashIndex;
  97
  98         protected:
  99         inline Group* OwnerPointer() const {
 100                 return (Owner != 0) ? Owner->GrpP : 0;
 101         }
 102
 103         public:
 104         // This constructor is the 'begin' constructor, never use it.
 105         inline GrpIterator(pkgCache &Owner) : Iterator<Group, GrpIterator>(Owner), HashIndex(-1) {
 106                 S = OwnerPointer();
 107                 operator ++(0);
 108         }
 109
 110         virtual void operator ++(int);
 111         virtual void operator ++() {operator ++(0);}
 112
 113         inline const char *Name() const {return S->Name == 0?0:Owner->StrP + S->Name;}
 114         inline PkgIterator PackageList() const;
 115         PkgIterator FindPkg(std::string Arch = "any") const;
 116         /** \brief find the package with the "best" architecture
 117
 118             The best architecture is either the "native" or the first
 119             in the list of Architectures which is not an end-Pointer
 120
 121             \param PreferNonVirtual tries to respond with a non-virtual package
 122                    and only if this fails returns the best virtual package */
 123         PkgIterator FindPreferredPkg(bool const &PreferNonVirtual = true) const;
 124         PkgIterator NextPkg(PkgIterator const &Pkg) const;
 125
 126         // Constructors
 127         inline GrpIterator(pkgCache &Owner, Group *Trg) : Iterator<Group, GrpIterator>(Owner, Trg), HashIndex(0) {
 128                 if (S == 0)
 129                         S = OwnerPointer();
 130         }
 131         inline GrpIterator() : Iterator<Group, GrpIterator>(), HashIndex(0) {}
 132
 133 };
 134                                                                         /*}}}*/
 135 // Package Iterator                                                     /*{{{*/
 136 class pkgCache::PkgIterator: public Iterator<Package, PkgIterator> {
 137         long HashIndex;
 138
 139         protected:
 140         inline Package* OwnerPointer() const {
 141                 return (Owner != 0) ? Owner->PkgP : 0;
 142         }
 143
 144         public:
 145         // This constructor is the 'begin' constructor, never use it.
 146         inline PkgIterator(pkgCache &Owner) : Iterator<Package, PkgIterator>(Owner), HashIndex(-1) {
 147                 S = OwnerPointer();
 148                 operator ++(0);
 149         }
 150
 151         virtual void operator ++(int);
 152         virtual void operator ++() {operator ++(0);}
 153
 154         enum OkState {NeedsNothing,NeedsUnpack,NeedsConfigure};
 155
 156         // Accessors
 157         inline const char *Name() const {return S->Name == 0?0:Owner->StrP + S->Name;}
 158         inline const char *Section() const {return S->Section == 0?0:Owner->StrP + S->Section;}
 159         inline bool Purge() const {return S->CurrentState == pkgCache::State::Purge ||
 160                 (S->CurrentVer == 0 && S->CurrentState == pkgCache::State::NotInstalled);}
 161         inline const char *Arch() const {return S->Arch == 0?0:Owner->StrP + S->Arch;}
 162         inline GrpIterator Group() const { return GrpIterator(*Owner, Owner->GrpP + S->Group);}
 163
 164         inline VerIterator VersionList() const;
 165         inline VerIterator CurrentVer() const;
 166         inline DepIterator RevDependsList() const;
 167         inline PrvIterator ProvidesList() const;
 168         OkState State() const;
 169         const char *CandVersion() const;
 170         const char *CurVersion() const;
 171
 172         //Nice printable representation
 173         friend std::ostream& operator <<(std::ostream& out, PkgIterator i);
 174         std::string FullName(bool const &Pretty = false) const;
 175
 176         // Constructors
 177         inline PkgIterator(pkgCache &Owner,Package *Trg) : Iterator<Package, PkgIterator>(Owner, Trg), HashIndex(0) {
 178                 if (S == 0)
 179                         S = OwnerPointer();
 180         }
 181         inline PkgIterator() : Iterator<Package, PkgIterator>(), HashIndex(0) {}
 182 };
 183                                                                         /*}}}*/
 184 // Version Iterator                                                     /*{{{*/
 185 class pkgCache::VerIterator : public Iterator<Version, VerIterator> {
 186         protected:
 187         inline Version* OwnerPointer() const {
 188                 return (Owner != 0) ? Owner->VerP : 0;
 189         }
 190
 191         public:
 192         // Iteration
 193         void operator ++(int) {if (S != Owner->VerP) S = Owner->VerP + S->NextVer;}
 194         inline void operator ++() {operator ++(0);}
 195
 196         // Comparison
 197         int CompareVer(const VerIterator &B) const;
 198         /** \brief compares two version and returns if they are similar
 199
 200             This method should be used to identify if two pseudo versions are
 201             referring to the same "real" version */
 202         inline bool SimilarVer(const VerIterator &B) const {
 203                 return (B.end() == false && S->Hash == B->Hash && strcmp(VerStr(), B.VerStr()) == 0);
 204         }
 205
 206         // Accessors
 207         inline const char *VerStr() const {return S->VerStr == 0?0:Owner->StrP + S->VerStr;}
 208         inline const char *Section() const {return S->Section == 0?0:Owner->StrP + S->Section;}
 209         inline const char *Arch() const {
 210                 if ((S->MultiArch & pkgCache::Version::All) == pkgCache::Version::All)
 211                         return "all";
 212                 return S->ParentPkg == 0?0:Owner->StrP + ParentPkg()->Arch;
 213         }
 214         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->ParentPkg);}
 215
 216         inline DescIterator DescriptionList() const;
 217         DescIterator TranslatedDescription() const;
 218         inline DepIterator DependsList() const;
 219         inline PrvIterator ProvidesList() const;
 220         inline VerFileIterator FileList() const;
 221         bool Downloadable() const;
 222         inline const char *PriorityType() const {return Owner->Priority(S->Priority);}
 223         const char *MultiArchType() const;
 224         std::string RelStr() const;
 225
 226         bool Automatic() const;
 227         VerFileIterator NewestFile() const;
 228
 229         inline VerIterator(pkgCache &Owner,Version *Trg = 0) : Iterator<Version, VerIterator>(Owner, Trg) {
 230                 if (S == 0)
 231                         S = OwnerPointer();
 232         }
 233         inline VerIterator() : Iterator<Version, VerIterator>() {}
 234 };
 235                                                                         /*}}}*/
 236 // Description Iterator                                                 /*{{{*/
 237 class pkgCache::DescIterator : public Iterator<Description, DescIterator> {
 238         protected:
 239         inline Description* OwnerPointer() const {
 240                 return (Owner != 0) ? Owner->DescP : 0;
 241         }
 242
 243         public:
 244         // Iteration
 245         void operator ++(int) {if (S != Owner->DescP) S = Owner->DescP + S->NextDesc;}
 246         inline void operator ++() {operator ++(0);}
 247
 248         // Comparison
 249         int CompareDesc(const DescIterator &B) const;
 250
 251         // Accessors
 252         inline const char *LanguageCode() const {return Owner->StrP + S->language_code;}
 253         inline const char *md5() const {return Owner->StrP + S->md5sum;}
 254         inline DescFileIterator FileList() const;
 255
 256         inline DescIterator() : Iterator<Description, DescIterator>() {}
 257         inline DescIterator(pkgCache &Owner,Description *Trg = 0) : Iterator<Description, DescIterator>(Owner, Trg) {
 258                 if (S == 0)
 259                         S = Owner.DescP;
 260         }
 261 };
 262                                                                         /*}}}*/
 263 // Dependency iterator                                                  /*{{{*/
 264 class pkgCache::DepIterator : public Iterator<Dependency, DepIterator> {
 265         enum {DepVer, DepRev} Type;
 266
 267         protected:
 268         inline Dependency* OwnerPointer() const {
 269                 return (Owner != 0) ? Owner->DepP : 0;
 270         }
 271
 272         public:
 273         // Iteration
 274         void operator ++(int) {if (S != Owner->DepP) S = Owner->DepP +
 275                 (Type == DepVer ? S->NextDepends : S->NextRevDepends);}
 276         inline void operator ++() {operator ++(0);}
 277
 278         // Accessors
 279         inline const char *TargetVer() const {return S->Version == 0?0:Owner->StrP + S->Version;}
 280         inline PkgIterator TargetPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->Package);}
 281         inline PkgIterator SmartTargetPkg() const {PkgIterator R(*Owner,0);SmartTargetPkg(R);return R;}
 282         inline VerIterator ParentVer() const {return VerIterator(*Owner,Owner->VerP + S->ParentVer);}
 283         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->ParentVer].ParentPkg);}
 284         inline bool Reverse() const {return Type == DepRev;}
 285         bool IsCritical() const;
 286         bool IsNegative() const;
 287         bool IsIgnorable(PrvIterator const &Prv) const;
 288         bool IsIgnorable(PkgIterator const &Pkg) const;
 289         bool IsMultiArchImplicit() const;
 290         bool IsSatisfied(VerIterator const &Ver) const;
 291         bool IsSatisfied(PrvIterator const &Prv) const;
 292         void GlobOr(DepIterator &Start,DepIterator &End);
 293         Version **AllTargets() const;
 294         bool SmartTargetPkg(PkgIterator &Result) const;
 295         inline const char *CompType() const {return Owner->CompType(S->CompareOp);}
 296         inline const char *DepType() const {return Owner->DepType(S->Type);}
 297
 298         //Nice printable representation
 299         friend std::ostream& operator <<(std::ostream& out, DepIterator D);
 300
 301         inline DepIterator(pkgCache &Owner, Dependency *Trg, Version* = 0) :
 302                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepVer) {
 303                 if (S == 0)
 304                         S = Owner.DepP;
 305         }
 306         inline DepIterator(pkgCache &Owner, Dependency *Trg, Package*) :
 307                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepRev) {
 308                 if (S == 0)
 309                         S = Owner.DepP;
 310         }
 311         inline DepIterator() : Iterator<Dependency, DepIterator>(), Type(DepVer) {}
 312 };
 313                                                                         /*}}}*/
 314 // Provides iterator                                                    /*{{{*/
 315 class pkgCache::PrvIterator : public Iterator<Provides, PrvIterator> {
 316         enum {PrvVer, PrvPkg} Type;
 317
 318         protected:
 319         inline Provides* OwnerPointer() const {
 320                 return (Owner != 0) ? Owner->ProvideP : 0;
 321         }
 322
 323         public:
 324         // Iteration
 325         void operator ++(int) {if (S != Owner->ProvideP) S = Owner->ProvideP +
 326                 (Type == PrvVer?S->NextPkgProv:S->NextProvides);}
 327         inline void operator ++() {operator ++(0);}
 328
 329         // Accessors
 330         inline const char *Name() const {return Owner->StrP + Owner->PkgP[S->ParentPkg].Name;}
 331         inline const char *ProvideVersion() const {return S->ProvideVersion == 0?0:Owner->StrP + S->ProvideVersion;}
 332         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->ParentPkg);}
 333         inline VerIterator OwnerVer() const {return VerIterator(*Owner,Owner->VerP + S->Version);}
 334         inline PkgIterator OwnerPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->Version].ParentPkg);}
 335
 336         bool IsMultiArchImplicit() const;
 337
 338         inline PrvIterator() : Iterator<Provides, PrvIterator>(), Type(PrvVer) {}
 339         inline PrvIterator(pkgCache &Owner, Provides *Trg, Version*) :
 340                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvVer) {
 341                 if (S == 0)
 342                         S = Owner.ProvideP;
 343         }
 344         inline PrvIterator(pkgCache &Owner, Provides *Trg, Package*) :
 345                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvPkg) {
 346                 if (S == 0)
 347                         S = Owner.ProvideP;
 348         }
 349 };
 350                                                                         /*}}}*/
 351 // Package file                                                         /*{{{*/
 352 class pkgCache::PkgFileIterator : public Iterator<PackageFile, PkgFileIterator> {
 353         protected:
 354         inline PackageFile* OwnerPointer() const {
 355                 return (Owner != 0) ? Owner->PkgFileP : 0;
 356         }
 357
 358         public:
 359         // Iteration
 360         void operator ++(int) {if (S != Owner->PkgFileP) S = Owner->PkgFileP + S->NextFile;}
 361         inline void operator ++() {operator ++(0);}
 362
 363         // Accessors
 364         inline const char *FileName() const {return S->FileName == 0?0:Owner->StrP + S->FileName;}
 365         inline const char *Archive() const {return S->Archive == 0?0:Owner->StrP + S->Archive;}
 366         inline const char *Component() const {return S->Component == 0?0:Owner->StrP + S->Component;}
 367         inline const char *Version() const {return S->Version == 0?0:Owner->StrP + S->Version;}
 368         inline const char *Origin() const {return S->Origin == 0?0:Owner->StrP + S->Origin;}
 369         inline const char *Codename() const {return S->Codename ==0?0:Owner->StrP + S->Codename;}
 370         inline const char *Label() const {return S->Label == 0?0:Owner->StrP + S->Label;}
 371         inline const char *Site() const {return S->Site == 0?0:Owner->StrP + S->Site;}
 372         inline const char *Architecture() const {return S->Architecture == 0?0:Owner->StrP + S->Architecture;}
 373         inline const char *IndexType() const {return S->IndexType == 0?0:Owner->StrP + S->IndexType;}
 374
 375         bool IsOk();
 376         std::string RelStr();
 377
 378         // Constructors
 379         inline PkgFileIterator() : Iterator<PackageFile, PkgFileIterator>() {}
 380         inline PkgFileIterator(pkgCache &Owner) : Iterator<PackageFile, PkgFileIterator>(Owner, Owner.PkgFileP) {}
 381         inline PkgFileIterator(pkgCache &Owner,PackageFile *Trg) : Iterator<PackageFile, PkgFileIterator>(Owner, Trg) {}
 382 };
 383                                                                         /*}}}*/
 384 // Version File                                                         /*{{{*/
 385 class pkgCache::VerFileIterator : public pkgCache::Iterator<VerFile, VerFileIterator> {
 386         protected:
 387         inline VerFile* OwnerPointer() const {
 388                 return (Owner != 0) ? Owner->VerFileP : 0;
 389         }
 390
 391         public:
 392         // Iteration
 393         void operator ++(int) {if (S != Owner->VerFileP) S = Owner->VerFileP + S->NextFile;}
 394         inline void operator ++() {operator ++(0);}
 395
 396         // Accessors
 397         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);}
 398
 399         inline VerFileIterator() : Iterator<VerFile, VerFileIterator>() {}
 400         inline VerFileIterator(pkgCache &Owner,VerFile *Trg) : Iterator<VerFile, VerFileIterator>(Owner, Trg) {}
 401 };
 402                                                                         /*}}}*/
 403 // Description File                                                     /*{{{*/
 404 class pkgCache::DescFileIterator : public Iterator<DescFile, DescFileIterator> {
 405         protected:
 406         inline DescFile* OwnerPointer() const {
 407                 return (Owner != 0) ? Owner->DescFileP : 0;
 408         }
 409
 410         public:
 411         // Iteration
 412         void operator ++(int) {if (S != Owner->DescFileP) S = Owner->DescFileP + S->NextFile;}
 413         inline void operator ++() {operator ++(0);}
 414
 415         // Accessors
 416         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);}
 417
 418         inline DescFileIterator() : Iterator<DescFile, DescFileIterator>() {}
 419         inline DescFileIterator(pkgCache &Owner,DescFile *Trg) : Iterator<DescFile, DescFileIterator>(Owner, Trg) {}
 420 };
 421                                                                         /*}}}*/
 422 // Inlined Begin functions can't be in the class because of order problems /*{{{*/
 423 inline pkgCache::PkgIterator pkgCache::GrpIterator::PackageList() const
 424        {return PkgIterator(*Owner,Owner->PkgP + S->FirstPackage);}
 425 inline pkgCache::VerIterator pkgCache::PkgIterator::VersionList() const
 426        {return VerIterator(*Owner,Owner->VerP + S->VersionList);}
 427 inline pkgCache::VerIterator pkgCache::PkgIterator::CurrentVer() const
 428        {return VerIterator(*Owner,Owner->VerP + S->CurrentVer);}
 429 inline pkgCache::DepIterator pkgCache::PkgIterator::RevDependsList() const
 430        {return DepIterator(*Owner,Owner->DepP + S->RevDepends,S);}
 431 inline pkgCache::PrvIterator pkgCache::PkgIterator::ProvidesList() const
 432        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);}
 433 inline pkgCache::DescIterator pkgCache::VerIterator::DescriptionList() const
 434        {return DescIterator(*Owner,Owner->DescP + S->DescriptionList);}
 435 inline pkgCache::PrvIterator pkgCache::VerIterator::ProvidesList() const
 436        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);}
 437 inline pkgCache::DepIterator pkgCache::VerIterator::DependsList() const
 438        {return DepIterator(*Owner,Owner->DepP + S->DependsList,S);}
 439 inline pkgCache::VerFileIterator pkgCache::VerIterator::FileList() const
 440        {return VerFileIterator(*Owner,Owner->VerFileP + S->FileList);}
 441 inline pkgCache::DescFileIterator pkgCache::DescIterator::FileList() const
 442        {return DescFileIterator(*Owner,Owner->DescFileP + S->FileList);}
 443                                                                         /*}}}*/
 444 #endif