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 stucture 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             refering 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)
 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         std::string RelStr() const;
 224
 225         bool Automatic() const;
 226         VerFileIterator NewestFile() const;
 227
 228         inline VerIterator(pkgCache &Owner,Version *Trg = 0) : Iterator<Version, VerIterator>(Owner, Trg) {
 229                 if (S == 0)
 230                         S = OwnerPointer();
 231         };
 232         inline VerIterator() : Iterator<Version, VerIterator>() {};
 233 };
 234                                                                         /*}}}*/
 235 // Description Iterator                                                 /*{{{*/
 236 class pkgCache::DescIterator : public Iterator<Description, DescIterator> {
 237         protected:
 238         inline Description* OwnerPointer() const {
 239                 return (Owner != 0) ? Owner->DescP : 0;
 240         };
 241
 242         public:
 243         // Iteration
 244         void operator ++(int) {if (S != Owner->DescP) S = Owner->DescP + S->NextDesc;};
 245         inline void operator ++() {operator ++(0);};
 246
 247         // Comparison
 248         int CompareDesc(const DescIterator &B) const;
 249
 250         // Accessors
 251         inline const char *LanguageCode() const {return Owner->StrP + S->language_code;};
 252         inline const char *md5() const {return Owner->StrP + S->md5sum;};
 253         inline DescFileIterator FileList() const;
 254
 255         inline DescIterator() : Iterator<Description, DescIterator>() {};
 256         inline DescIterator(pkgCache &Owner,Description *Trg = 0) : Iterator<Description, DescIterator>(Owner, Trg) {
 257                 if (S == 0)
 258                         S = Owner.DescP;
 259         };
 260 };
 261                                                                         /*}}}*/
 262 // Dependency iterator                                                  /*{{{*/
 263 class pkgCache::DepIterator : public Iterator<Dependency, DepIterator> {
 264         enum {DepVer, DepRev} Type;
 265
 266         protected:
 267         inline Dependency* OwnerPointer() const {
 268                 return (Owner != 0) ? Owner->DepP : 0;
 269         };
 270
 271         public:
 272         // Iteration
 273         void operator ++(int) {if (S != Owner->DepP) S = Owner->DepP +
 274                 (Type == DepVer ? S->NextDepends : S->NextRevDepends);};
 275         inline void operator ++() {operator ++(0);};
 276
 277         // Accessors
 278         inline const char *TargetVer() const {return S->Version == 0?0:Owner->StrP + S->Version;};
 279         inline PkgIterator TargetPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->Package);};
 280         inline PkgIterator SmartTargetPkg() const {PkgIterator R(*Owner,0);SmartTargetPkg(R);return R;};
 281         inline VerIterator ParentVer() const {return VerIterator(*Owner,Owner->VerP + S->ParentVer);};
 282         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->ParentVer].ParentPkg);};
 283         inline bool Reverse() const {return Type == DepRev;};
 284         bool IsCritical() const;
 285         bool IsNegative() const;
 286         bool IsIgnorable(PrvIterator const &Prv) const;
 287         bool IsIgnorable(PkgIterator const &Pkg) const;
 288         void GlobOr(DepIterator &Start,DepIterator &End);
 289         Version **AllTargets() const;
 290         bool SmartTargetPkg(PkgIterator &Result) const;
 291         inline const char *CompType() const {return Owner->CompType(S->CompareOp);};
 292         inline const char *DepType() const {return Owner->DepType(S->Type);};
 293
 294         //Nice printable representation
 295         friend std::ostream& operator <<(std::ostream& out, DepIterator D);
 296
 297         inline DepIterator(pkgCache &Owner, Dependency *Trg, Version* = 0) :
 298                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepVer) {
 299                 if (S == 0)
 300                         S = Owner.DepP;
 301         };
 302         inline DepIterator(pkgCache &Owner, Dependency *Trg, Package*) :
 303                 Iterator<Dependency, DepIterator>(Owner, Trg), Type(DepRev) {
 304                 if (S == 0)
 305                         S = Owner.DepP;
 306         };
 307         inline DepIterator() : Iterator<Dependency, DepIterator>(), Type(DepVer) {};
 308 };
 309                                                                         /*}}}*/
 310 // Provides iterator                                                    /*{{{*/
 311 class pkgCache::PrvIterator : public Iterator<Provides, PrvIterator> {
 312         enum {PrvVer, PrvPkg} Type;
 313
 314         protected:
 315         inline Provides* OwnerPointer() const {
 316                 return (Owner != 0) ? Owner->ProvideP : 0;
 317         };
 318
 319         public:
 320         // Iteration
 321         void operator ++(int) {if (S != Owner->ProvideP) S = Owner->ProvideP +
 322                 (Type == PrvVer?S->NextPkgProv:S->NextProvides);};
 323         inline void operator ++() {operator ++(0);};
 324
 325         // Accessors
 326         inline const char *Name() const {return Owner->StrP + Owner->PkgP[S->ParentPkg].Name;};
 327         inline const char *ProvideVersion() const {return S->ProvideVersion == 0?0:Owner->StrP + S->ProvideVersion;};
 328         inline PkgIterator ParentPkg() const {return PkgIterator(*Owner,Owner->PkgP + S->ParentPkg);};
 329         inline VerIterator OwnerVer() const {return VerIterator(*Owner,Owner->VerP + S->Version);};
 330         inline PkgIterator OwnerPkg() const {return PkgIterator(*Owner,Owner->PkgP + Owner->VerP[S->Version].ParentPkg);};
 331
 332         inline PrvIterator() : Iterator<Provides, PrvIterator>(), Type(PrvVer) {};
 333
 334         inline PrvIterator(pkgCache &Owner, Provides *Trg, Version*) :
 335                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvVer) {
 336                 if (S == 0)
 337                         S = Owner.ProvideP;
 338         };
 339         inline PrvIterator(pkgCache &Owner, Provides *Trg, Package*) :
 340                 Iterator<Provides, PrvIterator>(Owner, Trg), Type(PrvPkg) {
 341                 if (S == 0)
 342                         S = Owner.ProvideP;
 343         };
 344 };
 345                                                                         /*}}}*/
 346 // Package file                                                         /*{{{*/
 347 class pkgCache::PkgFileIterator : public Iterator<PackageFile, PkgFileIterator> {
 348         protected:
 349         inline PackageFile* OwnerPointer() const {
 350                 return (Owner != 0) ? Owner->PkgFileP : 0;
 351         };
 352
 353         public:
 354         // Iteration
 355         void operator ++(int) {if (S != Owner->PkgFileP) S = Owner->PkgFileP + S->NextFile;};
 356         inline void operator ++() {operator ++(0);};
 357
 358         // Accessors
 359         inline const char *FileName() const {return S->FileName == 0?0:Owner->StrP + S->FileName;};
 360         inline const char *Archive() const {return S->Archive == 0?0:Owner->StrP + S->Archive;};
 361         inline const char *Component() const {return S->Component == 0?0:Owner->StrP + S->Component;};
 362         inline const char *Version() const {return S->Version == 0?0:Owner->StrP + S->Version;};
 363         inline const char *Origin() const {return S->Origin == 0?0:Owner->StrP + S->Origin;};
 364         inline const char *Codename() const {return S->Codename ==0?0:Owner->StrP + S->Codename;};
 365         inline const char *Label() const {return S->Label == 0?0:Owner->StrP + S->Label;};
 366         inline const char *Site() const {return S->Site == 0?0:Owner->StrP + S->Site;};
 367         inline const char *Architecture() const {return S->Architecture == 0?0:Owner->StrP + S->Architecture;};
 368         inline const char *IndexType() const {return S->IndexType == 0?0:Owner->StrP + S->IndexType;};
 369
 370         bool IsOk();
 371         std::string RelStr();
 372
 373         // Constructors
 374         inline PkgFileIterator() : Iterator<PackageFile, PkgFileIterator>() {};
 375         inline PkgFileIterator(pkgCache &Owner) : Iterator<PackageFile, PkgFileIterator>(Owner, Owner.PkgFileP) {};
 376         inline PkgFileIterator(pkgCache &Owner,PackageFile *Trg) : Iterator<PackageFile, PkgFileIterator>(Owner, Trg) {};
 377 };
 378                                                                         /*}}}*/
 379 // Version File                                                         /*{{{*/
 380 class pkgCache::VerFileIterator : public pkgCache::Iterator<VerFile, VerFileIterator> {
 381         protected:
 382         inline VerFile* OwnerPointer() const {
 383                 return (Owner != 0) ? Owner->VerFileP : 0;
 384         };
 385
 386         public:
 387         // Iteration
 388         void operator ++(int) {if (S != Owner->VerFileP) S = Owner->VerFileP + S->NextFile;};
 389         inline void operator ++() {operator ++(0);};
 390
 391         // Accessors
 392         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);};
 393
 394         inline VerFileIterator() : Iterator<VerFile, VerFileIterator>() {};
 395         inline VerFileIterator(pkgCache &Owner,VerFile *Trg) : Iterator<VerFile, VerFileIterator>(Owner, Trg) {};
 396 };
 397                                                                         /*}}}*/
 398 // Description File                                                     /*{{{*/
 399 class pkgCache::DescFileIterator : public Iterator<DescFile, DescFileIterator> {
 400         protected:
 401         inline DescFile* OwnerPointer() const {
 402                 return (Owner != 0) ? Owner->DescFileP : 0;
 403         };
 404
 405         public:
 406         // Iteration
 407         void operator ++(int) {if (S != Owner->DescFileP) S = Owner->DescFileP + S->NextFile;};
 408         inline void operator ++() {operator ++(0);};
 409
 410         // Accessors
 411         inline PkgFileIterator File() const {return PkgFileIterator(*Owner,S->File + Owner->PkgFileP);};
 412
 413         inline DescFileIterator() : Iterator<DescFile, DescFileIterator>() {};
 414         inline DescFileIterator(pkgCache &Owner,DescFile *Trg) : Iterator<DescFile, DescFileIterator>(Owner, Trg) {};
 415 };
 416                                                                         /*}}}*/
 417 // Inlined Begin functions cant be in the class because of order problems /*{{{*/
 418 inline pkgCache::PkgIterator pkgCache::GrpIterator::PackageList() const
 419        {return PkgIterator(*Owner,Owner->PkgP + S->FirstPackage);};
 420 inline pkgCache::VerIterator pkgCache::PkgIterator::VersionList() const
 421        {return VerIterator(*Owner,Owner->VerP + S->VersionList);};
 422 inline pkgCache::VerIterator pkgCache::PkgIterator::CurrentVer() const
 423        {return VerIterator(*Owner,Owner->VerP + S->CurrentVer);};
 424 inline pkgCache::DepIterator pkgCache::PkgIterator::RevDependsList() const
 425        {return DepIterator(*Owner,Owner->DepP + S->RevDepends,S);};
 426 inline pkgCache::PrvIterator pkgCache::PkgIterator::ProvidesList() const
 427        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);};
 428 inline pkgCache::DescIterator pkgCache::VerIterator::DescriptionList() const
 429        {return DescIterator(*Owner,Owner->DescP + S->DescriptionList);};
 430 inline pkgCache::PrvIterator pkgCache::VerIterator::ProvidesList() const
 431        {return PrvIterator(*Owner,Owner->ProvideP + S->ProvidesList,S);};
 432 inline pkgCache::DepIterator pkgCache::VerIterator::DependsList() const
 433        {return DepIterator(*Owner,Owner->DepP + S->DependsList,S);};
 434 inline pkgCache::VerFileIterator pkgCache::VerIterator::FileList() const
 435        {return VerFileIterator(*Owner,Owner->VerFileP + S->FileList);};
 436 inline pkgCache::DescFileIterator pkgCache::DescIterator::FileList() const
 437        {return DescFileIterator(*Owner,Owner->DescFileP + S->FileList);};
 438                                                                         /*}}}*/
 439 #endif