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         void ReMap(void const * const oldMap, void const * const newMap) {
  79                 if (Owner == 0 || S == 0)
  80                         return;
  81                 S += (Str*)(newMap) - (Str*)(oldMap);
  82         }
  83
  84         // Constructors - look out for the variable assigning
  85         inline Iterator() : S(0), Owner(0) {};
  86         inline Iterator(pkgCache &Owner,Str *T = 0) : S(T), Owner(&Owner) {};
  87 };
  88                                                                         /*}}}*/
  89 // Group Iterator                                                       /*{{{*/
  90 /* Packages with the same name are collected in a Group so someone only
  91    interest in package names can iterate easily over the names, so the
  92    different architectures can be treated as of the "same" package
  93    (apt internally treat them as totally different packages) */
  94 class pkgCache::GrpIterator: public Iterator<Group, GrpIterator> {
  95         long HashIndex;
  96
  97         protected:
  98         inline Group* OwnerPointer() const {
  99                 return (Owner != 0) ? Owner->GrpP : 0;
 100         };
 101
 102         public:
 103         // This constructor is the 'begin' constructor, never use it.
 104         inline GrpIterator(pkgCache &Owner) : Iterator<Group, GrpIterator>(Owner), HashIndex(-1) {
 105                 S = OwnerPointer();
 106                 operator ++(0);
 107         };
 108
 109         virtual void operator ++(int);
 110         virtual void operator ++() {operator ++(0);};
 111
 112         inline const char *Name() const {return S->Name == 0?0:Owner->StrP + S->Name;};
 113         inline PkgIterator PackageList() const;
 114         PkgIterator FindPkg(string Arch = "any") const;
 115         /** \brief find the package with the "best" architecture
 116
 117             The best architecture is either the "native" or the first
 118             in the list of Architectures which is not an end-Pointer
 119
 120             \param PreferNonVirtual tries to respond with a non-virtual package
 121                    and only if this fails returns the best virtual package */
 122         PkgIterator FindPreferredPkg(bool const &PreferNonVirtual = true) const;
 123         PkgIterator NextPkg(PkgIterator const &Pkg) const;
 124
 125         // Constructors
 126         inline GrpIterator(pkgCache &Owner, Group *Trg) : Iterator<Group, GrpIterator>(Owner, Trg), HashIndex(0) {
 127                 if (S == 0)
 128                         S = OwnerPointer();
 129         };
 130         inline GrpIterator() : Iterator<Group, GrpIterator>(), HashIndex(0) {};
 131
 132 };
 133                                                                         /*}}}*/
 134 // Package Iterator                                                     /*{{{*/
 135 class pkgCache::PkgIterator: public Iterator<Package, PkgIterator> {
 136         long HashIndex;
 137
 138         protected:
 139         inline Package* OwnerPointer() const {
 140                 return (Owner != 0) ? Owner->PkgP : 0;
 141         };
 142
 143         public:
 144         // This constructor is the 'begin' constructor, never use it.
 145         inline PkgIterator(pkgCache &Owner) : Iterator<Package, PkgIterator>(Owner), HashIndex(-1) {
 146                 S = OwnerPointer();
 147                 operator ++(0);
 148         };
 149
 150         virtual void operator ++(int);
 151         virtual void operator ++() {operator ++(0);};
 152
 153         enum OkState {NeedsNothing,NeedsUnpack,NeedsConfigure};
 154
 155         // Accessors
 156         inline const char *Name() const {return S->Name == 0?0:Owner->StrP + S->Name;};
 157         inline const char *Section() const {return S->Section == 0?0:Owner->StrP + S->Section;};
 158         inline bool Purge() const {return S->CurrentState == pkgCache::State::Purge ||
 159                 (S->CurrentVer == 0 && S->CurrentState == pkgCache::State::NotInstalled);};
 160         inline const char *Arch() const {return S->Arch == 0?0:Owner->StrP + S->Arch;};
 161         inline GrpIterator Group() const { return GrpIterator(*Owner, Owner->GrpP + S->Group);};
 162
 163         inline VerIterator VersionList() const;
 164         inline VerIterator CurrentVer() const;
 165         inline DepIterator RevDependsList() const;
 166         inline PrvIterator ProvidesList() const;
 167         OkState State() const;
 168         const char *CandVersion() const;
 169         const char *CurVersion() const;
 170
 171         //Nice printable representation
 172         friend std::ostream& operator <<(std::ostream& out, PkgIterator i);
 173         std::string FullName(bool const &Pretty = false) const;
 174
 175         // Constructors
 176         inline PkgIterator(pkgCache &Owner,Package *Trg) : Iterator<Package, PkgIterator>(Owner, Trg), HashIndex(0) {
 177                 if (S == 0)
 178                         S = OwnerPointer();
 179         };
 180         inline PkgIterator() : Iterator<Package, PkgIterator>(), HashIndex(0) {};
 181 };
 182                                                                         /*}}}*/
 183 // Version Iterator                                                     /*{{{*/
 184 class pkgCache::VerIterator : public Iterator<Version, VerIterator> {
 185         protected:
 186         inline Version* OwnerPointer() const {
 187                 return (Owner != 0) ? Owner->VerP : 0;
 188         };
 189
 190         public:
 191         // Iteration
 192         void operator ++(int) {if (S != Owner->VerP) S = Owner->VerP + S->NextVer;};
 193         inline void operator ++() {operator ++(0);};
 194
 195         // Comparison
 196         int CompareVer(const VerIterator &B) const;
 197         /** \brief compares two version and returns if they are similar
 198
 199             This method should be used to identify if two pseudo versions are
 200             refering to the same "real" version */
 201         inline bool SimilarVer(const VerIterator &B) const {
 202                 return (B.end() == false && S->Hash == B->Hash && strcmp(VerStr(), B.VerStr()) == 0);
 203         };
 204
 205         // Accessors
 206         inline const char *VerStr() const {return S->VerStr == 0?0:Owner->StrP + S->VerStr;};
 207         inline const char *Section() const {return S->Section == 0?0:Owner->StrP + S->Section;};
 208         inline const char *Arch() const {
 209                 if (S->MultiArch == pkgCache::Version::All)
 210                         return "all";
 211                 return S->ParentPkg == 0?0:Owner->StrP + ParentPkg()->Arch;
 212         };
 213         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->ParentPkg);};
 214
 215         inline DescIterator DescriptionList() const;
 216         DescIterator TranslatedDescription() const;
 217         inline DepIterator DependsList() const;
 218         inline PrvIterator ProvidesList() const;
 219         inline VerFileIterator FileList() const;
 220         bool Downloadable() const;
 221         inline const char *PriorityType() const {return Owner->Priority(S->Priority);};
 222         string RelStr() const;
 223
 224         bool Automatic() const;
 225         VerFileIterator NewestFile() const;
 226
 227         inline VerIterator(pkgCache &Owner,Version *Trg = 0) : Iterator<Version, VerIterator>(Owner, Trg) {
 228                 if (S == 0)
 229                         S = OwnerPointer();
 230         };
 231         inline VerIterator() : Iterator<Version, VerIterator>() {};
 232 };
 233                                                                         /*}}}*/
 234 // Description Iterator                                                 /*{{{*/
 235 class pkgCache::DescIterator : public Iterator<Description, DescIterator> {
 236         protected:
 237         inline Description* OwnerPointer() const {
 238                 return (Owner != 0) ? Owner->DescP : 0;
 239         };
 240
 241         public:
 242         // Iteration
 243         void operator ++(int) {if (S != Owner->DescP) S = Owner->DescP + S->NextDesc;};
 244         inline void operator ++() {operator ++(0);};
 245
 246         // Comparison
 247         int CompareDesc(const DescIterator &B) const;
 248
 249         // Accessors
 250         inline const char *LanguageCode() const {return Owner->StrP + S->language_code;};
 251         inline const char *md5() const {return Owner->StrP + S->md5sum;};
 252         inline DescFileIterator FileList() const;
 253
 254         inline DescIterator() : Iterator<Description, DescIterator>() {};
 255         inline DescIterator(pkgCache &Owner,Description *Trg = 0) : Iterator<Description, DescIterator>(Owner, Trg) {
 256                 if (S == 0)
 257                         S = Owner.DescP;
 258         };
 259 };
 260                                                                         /*}}}*/
 261 // Dependency iterator                                                  /*{{{*/
 262 class pkgCache::DepIterator : public Iterator<Dependency, DepIterator> {
 263         enum {DepVer, DepRev} Type;
 264
 265         protected:
 266         inline Dependency* OwnerPointer() const {
 267                 return (Owner != 0) ? Owner->DepP : 0;
 268         };
 269
 270         public:
 271         // Iteration
 272         void operator ++(int) {if (S != Owner->DepP) S = Owner->DepP +
 273                 (Type == DepVer ? S->NextDepends : S->NextRevDepends);};
 274         inline void operator ++() {operator ++(0);};
 275
 276         // Accessors
 277         inline const char *TargetVer() const {return S->Version == 0?0:Owner->StrP + S->Version;};
 278         inline PkgIterator TargetPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->Package);};
 279         inline PkgIterator SmartTargetPkg() const {PkgIterator R(*Owner,0);SmartTargetPkg(R);return R;};
 280         inline VerIterator ParentVer() const {return VerIterator(*Owner,Owner->VerP + S->ParentVer);};
 281         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->ParentVer].ParentPkg);};
 282         inline bool Reverse() const {return Type == DepRev;};
 283         bool IsCritical() const;
 284         bool IsNegative() const;
 285         void GlobOr(DepIterator &Start,DepIterator &End);
 286         Version **AllTargets() const;
 287         bool SmartTargetPkg(PkgIterator &Result) const;
 288         inline const char *CompType() const {return Owner->CompType(S->CompareOp);};
 289         inline const char *DepType() const {return Owner->DepType(S->Type);};
 290
 291         //Nice printable representation
 292         friend std::ostream& operator <<(std::ostream& out, DepIterator D);
 293
 294         inline DepIterator(pkgCache &Owner, Dependency *Trg, Version* = 0) :
 295                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepVer) {
 296                 if (S == 0)
 297                         S = Owner.DepP;
 298         };
 299         inline DepIterator(pkgCache &Owner, Dependency *Trg, Package*) :
 300                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepRev) {
 301                 if (S == 0)
 302                         S = Owner.DepP;
 303         };
 304         inline DepIterator() : Iterator<Dependency, DepIterator>(), Type(DepVer) {};
 305 };
 306                                                                         /*}}}*/
 307 // Provides iterator                                                    /*{{{*/
 308 class pkgCache::PrvIterator : public Iterator<Provides, PrvIterator> {
 309         enum {PrvVer, PrvPkg} Type;
 310
 311         protected:
 312         inline Provides* OwnerPointer() const {
 313                 return (Owner != 0) ? Owner->ProvideP : 0;
 314         };
 315
 316         public:
 317         // Iteration
 318         void operator ++(int) {if (S != Owner->ProvideP) S = Owner->ProvideP +
 319                 (Type == PrvVer?S->NextPkgProv:S->NextProvides);};
 320         inline void operator ++() {operator ++(0);};
 321
 322         // Accessors
 323         inline const char *Name() const {return Owner->StrP + Owner->PkgP[S->ParentPkg].Name;};
 324         inline const char *ProvideVersion() const {return S->ProvideVersion == 0?0:Owner->StrP + S->ProvideVersion;};
 325         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->ParentPkg);};
 326         inline VerIterator OwnerVer() const {return VerIterator(*Owner,Owner->VerP + S->Version);};
 327         inline PkgIterator OwnerPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->Version].ParentPkg);};
 328
 329         inline PrvIterator() : Iterator<Provides, PrvIterator>(), Type(PrvVer) {};
 330
 331         inline PrvIterator(pkgCache &Owner, Provides *Trg, Version*) :
 332                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvVer) {
 333                 if (S == 0)
 334                         S = Owner.ProvideP;
 335         };
 336         inline PrvIterator(pkgCache &Owner, Provides *Trg, Package*) :
 337                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvPkg) {
 338                 if (S == 0)
 339                         S = Owner.ProvideP;
 340         };
 341 };
 342                                                                         /*}}}*/
 343 // Package file                                                         /*{{{*/
 344 class pkgCache::PkgFileIterator : public Iterator<PackageFile, PkgFileIterator> {
 345         protected:
 346         inline PackageFile* OwnerPointer() const {
 347                 return (Owner != 0) ? Owner->PkgFileP : 0;
 348         };
 349
 350         public:
 351         // Iteration
 352         void operator ++(int) {if (S != Owner->PkgFileP) S = Owner->PkgFileP + S->NextFile;};
 353         inline void operator ++() {operator ++(0);};
 354
 355         // Accessors
 356         inline const char *FileName() const {return S->FileName == 0?0:Owner->StrP + S->FileName;};
 357         inline const char *Archive() const {return S->Archive == 0?0:Owner->StrP + S->Archive;};
 358         inline const char *Component() const {return S->Component == 0?0:Owner->StrP + S->Component;};
 359         inline const char *Version() const {return S->Version == 0?0:Owner->StrP + S->Version;};
 360         inline const char *Origin() const {return S->Origin == 0?0:Owner->StrP + S->Origin;};
 361         inline const char *Codename() const {return S->Codename ==0?0:Owner->StrP + S->Codename;};
 362         inline const char *Label() const {return S->Label == 0?0:Owner->StrP + S->Label;};
 363         inline const char *Site() const {return S->Site == 0?0:Owner->StrP + S->Site;};
 364         inline const char *Architecture() const {return S->Architecture == 0?0:Owner->StrP + S->Architecture;};
 365         inline const char *IndexType() const {return S->IndexType == 0?0:Owner->StrP + S->IndexType;};
 366
 367         bool IsOk();
 368         string RelStr();
 369
 370         // Constructors
 371         inline PkgFileIterator() : Iterator<PackageFile, PkgFileIterator>() {};
 372         inline PkgFileIterator(pkgCache &Owner) : Iterator<PackageFile, PkgFileIterator>(Owner, Owner.PkgFileP) {};
 373         inline PkgFileIterator(pkgCache &Owner,PackageFile *Trg) : Iterator<PackageFile, PkgFileIterator>(Owner, Trg) {};
 374 };
 375                                                                         /*}}}*/
 376 // Version File                                                         /*{{{*/
 377 class pkgCache::VerFileIterator : public pkgCache::Iterator<VerFile, VerFileIterator> {
 378         protected:
 379         inline VerFile* OwnerPointer() const {
 380                 return (Owner != 0) ? Owner->VerFileP : 0;
 381         };
 382
 383         public:
 384         // Iteration
 385         void operator ++(int) {if (S != Owner->VerFileP) S = Owner->VerFileP + S->NextFile;};
 386         inline void operator ++() {operator ++(0);};
 387
 388         // Accessors
 389         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);};
 390
 391         inline VerFileIterator() : Iterator<VerFile, VerFileIterator>() {};
 392         inline VerFileIterator(pkgCache &Owner,VerFile *Trg) : Iterator<VerFile, VerFileIterator>(Owner, Trg) {};
 393 };
 394                                                                         /*}}}*/
 395 // Description File                                                     /*{{{*/
 396 class pkgCache::DescFileIterator : public Iterator<DescFile, DescFileIterator> {
 397         protected:
 398         inline DescFile* OwnerPointer() const {
 399                 return (Owner != 0) ? Owner->DescFileP : 0;
 400         };
 401
 402         public:
 403         // Iteration
 404         void operator ++(int) {if (S != Owner->DescFileP) S = Owner->DescFileP + S->NextFile;};
 405         inline void operator ++() {operator ++(0);};
 406
 407         // Accessors
 408         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);};
 409
 410         inline DescFileIterator() : Iterator<DescFile, DescFileIterator>() {};
 411         inline DescFileIterator(pkgCache &Owner,DescFile *Trg) : Iterator<DescFile, DescFileIterator>(Owner, Trg) {};
 412 };
 413                                                                         /*}}}*/
 414 // Inlined Begin functions cant be in the class because of order problems /*{{{*/
 415 inline pkgCache::PkgIterator pkgCache::GrpIterator::PackageList() const
 416        {return PkgIterator(*Owner,Owner->PkgP + S->FirstPackage);};
 417 inline pkgCache::VerIterator pkgCache::PkgIterator::VersionList() const
 418        {return VerIterator(*Owner,Owner->VerP + S->VersionList);};
 419 inline pkgCache::VerIterator pkgCache::PkgIterator::CurrentVer() const
 420        {return VerIterator(*Owner,Owner->VerP + S->CurrentVer);};
 421 inline pkgCache::DepIterator pkgCache::PkgIterator::RevDependsList() const
 422        {return DepIterator(*Owner,Owner->DepP + S->RevDepends,S);};
 423 inline pkgCache::PrvIterator pkgCache::PkgIterator::ProvidesList() const
 424        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);};
 425 inline pkgCache::DescIterator pkgCache::VerIterator::DescriptionList() const
 426        {return DescIterator(*Owner,Owner->DescP + S->DescriptionList);};
 427 inline pkgCache::PrvIterator pkgCache::VerIterator::ProvidesList() const
 428        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);};
 429 inline pkgCache::DepIterator pkgCache::VerIterator::DependsList() const
 430        {return DepIterator(*Owner,Owner->DepP + S->DependsList,S);};
 431 inline pkgCache::VerFileIterator pkgCache::VerIterator::FileList() const
 432        {return VerFileIterator(*Owner,Owner->VerFileP + S->FileList);};
 433 inline pkgCache::DescFileIterator pkgCache::DescIterator::FileList() const
 434        {return DescFileIterator(*Owner,Owner->DescFileP + S->FileList);};
 435                                                                         /*}}}*/
 436 #endif