pkgcachegen.h

// -*- mode: cpp; mode: fold -*-
// Description                                                          /*{{{*/
/* ######################################################################
 
   Package Cache Generator - Generator for the cache structure.
 
   This builds the cache structure from the abstract package list parser.
   Each archive source has it's own list parser that is instantiated by
   the caller to provide data for the generator.
 
   Parts of the cache are created by this generator class while other
   parts are created by the list parser. The list parser is responsible
   for creating version, depends and provides structures, and some of
   their contents
 
   ##################################################################### */
                                                                        /*}}}*/
#ifndef PKGLIB_PKGCACHEGEN_H
#define PKGLIB_PKGCACHEGEN_H
 
#include <apt-pkg/macros.h>
#include <apt-pkg/mmap.h>
#include <apt-pkg/pkgcache.h>
 
#include <string>
#include <string_view>
#include <vector>
#if __cplusplus >= 201103L
#include <unordered_set>
#endif
 
#ifdef APT_COMPILING_APT
#include <xxhash.h>
#endif
 
class FileFd;
class pkgSourceList;
class OpProgress;
class pkgIndexFile;
class pkgCacheListParser;
 
class APT_HIDDEN pkgCacheGenerator                                      /*{{{*/
{
   APT_HIDDEN map_stringitem_t WriteStringInMap(std::string_view String) { return WriteStringInMap(String.data(), String.size()); };
   APT_HIDDEN map_stringitem_t WriteStringInMap(const char *String);
   APT_HIDDEN map_stringitem_t WriteStringInMap(const char *String, const unsigned long &Len);
   APT_HIDDEN uint32_t AllocateInMap(const unsigned long &size);
   template<typename T> map_pointer<T> AllocateInMap() {
      return map_pointer<T>{AllocateInMap(sizeof(T))};
   }
 
   // Dirty hack for public users that do not use C++11 yet
#if __cplusplus >= 201103L && defined(APT_COMPILING_APT)
   struct string_pointer {
      const char *data_;
      size_t size;
      pkgCacheGenerator *generator;
      map_stringitem_t item;
 
      const char *data() const {
         return data_ != nullptr ? data_ : static_cast<char*>(generator->Map.Data()) + item;
      }
 
      bool operator ==(string_pointer const &other) const {
         return size == other.size && memcmp(data(), other.data(), size) == 0;
      }
   };
   struct hash {
      uint32_t operator()(string_pointer const &that) const {
         return XXH3_64bits(that.data(), that.size) & 0xFFFFFFFF;
      }
   };
 
   std::unordered_set<string_pointer, hash> strMixed;
   std::unordered_set<string_pointer, hash> strVersions;
   std::unordered_set<string_pointer, hash> strSections;
#endif
 
   struct VersionExtra
   {
      char SHA256[64];
   };
   std::vector<VersionExtra> VersionExtra;
 
   friend class pkgCacheListParser;
   typedef pkgCacheListParser ListParser;
 
   public:
 
   template<typename Iter> class Dynamic {
      public:
      static std::vector<Iter*> toReMap;
      explicit Dynamic(Iter &I) {
         toReMap.push_back(&I);
      }
 
      ~Dynamic() {
         toReMap.pop_back();
      }
 
#if __cplusplus >= 201103L
      Dynamic(const Dynamic&) = delete;
      void operator=(const Dynamic&) = delete;
#endif
   };
 
   protected:
 
   DynamicMMap &Map;
   pkgCache Cache;
   OpProgress *Progress;
 
   std::string RlsFileName;
   pkgCache::ReleaseFile *CurrentRlsFile;
   std::string PkgFileName;
   pkgCache::PackageFile *CurrentFile;
 
   bool NewGroup(pkgCache::GrpIterator &Grp, std::string_view Name);
   bool NewPackage(pkgCache::PkgIterator &Pkg, std::string_view Name, std::string_view Arch);
   map_pointer<pkgCache::Version> NewVersion(pkgCache::VerIterator &Ver, std::string_view VerStr,
                            map_pointer<pkgCache::Package> const ParentPkg, uint32_t Hash,
                            map_pointer<pkgCache::Version> const Next);
   map_pointer<pkgCache::Description> NewDescription(pkgCache::DescIterator &Desc,const std::string &Lang, std::string_view md5sum,map_stringitem_t const idxmd5str);
   bool NewFileVer(pkgCache::VerIterator &Ver,ListParser &List);
   bool NewFileDesc(pkgCache::DescIterator &Desc,ListParser &List);
   bool NewDepends(pkgCache::PkgIterator &Pkg, pkgCache::VerIterator &Ver,
                   map_stringitem_t const Version, uint8_t const Op,
                   uint8_t const Type, map_pointer<pkgCache::Dependency>* &OldDepLast);
   bool NewProvides(pkgCache::VerIterator &Ver, pkgCache::PkgIterator &Pkg,
                    map_stringitem_t const ProvidesVersion, uint8_t const Flags);
 
   public:
 
   enum StringType { MIXED, VERSIONNUMBER, SECTION };
   map_stringitem_t StoreString(StringType const type, const char * S, unsigned int const Size);
 
   inline map_stringitem_t StoreString(enum StringType const type, std::string_view S) {return StoreString(type, S.data(),S.length());};
 
   void DropProgress() {Progress = 0;};
   bool SelectFile(const std::string &File,pkgIndexFile const &Index, std::string const &Architecture, std::string const &Component, unsigned long Flags = 0);
   bool SelectReleaseFile(const std::string &File, const std::string &Site, unsigned long Flags = 0);
   bool MergeList(ListParser &List,pkgCache::VerIterator *Ver = 0);
   inline pkgCache &GetCache() {return Cache;};
   inline pkgCache::PkgFileIterator GetCurFile()
         {return pkgCache::PkgFileIterator(Cache,CurrentFile);};
   inline pkgCache::RlsFileIterator GetCurRlsFile()
         {return pkgCache::RlsFileIterator(Cache,CurrentRlsFile);};
 
   APT_PUBLIC static bool MakeStatusCache(pkgSourceList &List,OpProgress *Progress,
                        MMap **OutMap = 0,bool AllowMem = false);
   APT_HIDDEN static bool MakeStatusCache(pkgSourceList &List,OpProgress *Progress,
                        MMap **OutMap,pkgCache **OutCache, bool AllowMem = false);
   APT_PUBLIC static bool MakeOnlyStatusCache(OpProgress *Progress,DynamicMMap **OutMap);
 
   void ReMap(void const * const oldMap, void * const newMap, size_t oldSize);
   bool Start();
 
   pkgCacheGenerator(DynamicMMap *Map,OpProgress *Progress);
   virtual ~pkgCacheGenerator();
 
   private:
   void * const d;
   APT_HIDDEN bool MergeListGroup(ListParser &List, std::string const &GrpName);
   APT_HIDDEN bool MergeListPackage(ListParser &List, pkgCache::PkgIterator &Pkg);
   APT_HIDDEN bool MergeListVersion(ListParser &List, pkgCache::PkgIterator &Pkg,
                         std::string_view Version, pkgCache::VerIterator* &OutVer);
 
   APT_HIDDEN bool AddImplicitDepends(pkgCache::GrpIterator &G, pkgCache::PkgIterator &P,
                           pkgCache::VerIterator &V);
   APT_HIDDEN bool AddImplicitDepends(pkgCache::VerIterator &V, pkgCache::PkgIterator &D);
 
   APT_HIDDEN bool AddNewDescription(ListParser &List, pkgCache::VerIterator &Ver,
         std::string const &lang, std::string_view CurMd5, map_stringitem_t &md5idx);
};
                                                                        /*}}}*/
// This is the abstract package list parser class.                      /*{{{*/
class APT_HIDDEN pkgCacheListParser
{
   pkgCacheGenerator *Owner;
   friend class pkgCacheGenerator;
 
   // Some cache items
   pkgCache::VerIterator OldDepVer;
   map_pointer<pkgCache::Dependency> *OldDepLast;
 
   void * const d;
 
   protected:
   inline bool NewGroup(pkgCache::GrpIterator &Grp, std::string_view Name) { return Owner->NewGroup(Grp, Name); }
   inline map_stringitem_t StoreString(pkgCacheGenerator::StringType const type, const char *S,unsigned int Size) {return Owner->StoreString(type, S, Size);};
   inline map_stringitem_t StoreString(pkgCacheGenerator::StringType const type, std::string_view S) {return Owner->StoreString(type, S);};
   inline map_stringitem_t WriteString(std::string_view S) {return Owner->WriteStringInMap(S.data(), S.size());};
 
   inline map_stringitem_t WriteString(const char *S,unsigned int Size) {return Owner->WriteStringInMap(S,Size);};
   bool NewDepends(pkgCache::VerIterator &Ver,std::string_view Package, std::string_view Arch,
                   std::string_view Version,uint8_t const Op,
                   uint8_t const Type);
   bool NewProvides(pkgCache::VerIterator &Ver,std::string_view PkgName,
                    std::string_view PkgArch, std::string_view Version,
                    uint8_t const Flags);
   bool NewProvidesAllArch(pkgCache::VerIterator &Ver, std::string_view Package,
                           std::string_view Version, uint8_t const Flags);
   public:
 
   // These all operate against the current section
   virtual std::string Package() = 0;
   virtual bool ArchitectureAll() = 0;
   virtual std::string_view Architecture() = 0;
   virtual std::string_view Version() = 0;
   virtual bool NewVersion(pkgCache::VerIterator &Ver) = 0;
   virtual std::vector<std::string> AvailableDescriptionLanguages() = 0;
   virtual std::string_view Description_md5() = 0;
   virtual uint32_t VersionHash() = 0;
   virtual bool SameVersion(uint32_t Hash, pkgCache::VerIterator const &Ver);
   virtual bool UsePackage(pkgCache::PkgIterator &Pkg,
                           pkgCache::VerIterator &Ver) = 0;
   virtual map_filesize_t Offset() = 0;
   virtual map_filesize_t Size() = 0;
 
   virtual bool Step() = 0;
 
   virtual bool CollectFileProvides(pkgCache &/*Cache*/,
                                    pkgCache::VerIterator &/*Ver*/) {return true;};
 
   pkgCacheListParser();
   virtual ~pkgCacheListParser();
};
                                                                        /*}}}*/
 
#endif