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