From 885594fc8831d1be5a254557385e3dbefb564fbf Mon Sep 17 00:00:00 2001 From: David Kalnischkies Date: Wed, 3 Apr 2013 19:43:03 +0200 Subject: [PATCH] share version strings between same versions (of different architectures) to save some space and allow quick comparisions later on --- apt-pkg/deb/debversion.cc | 12 ++++-------- apt-pkg/pkgcachegen.cc | 37 +++++++++++++++++++++++++++++++------ apt-pkg/pkgcachegen.h | 6 +++++- debian/changelog | 2 ++ 4 files changed, 42 insertions(+), 15 deletions(-) diff --git a/apt-pkg/deb/debversion.cc b/apt-pkg/deb/debversion.cc index 94d35784..14056126 100644 --- a/apt-pkg/deb/debversion.cc +++ b/apt-pkg/deb/debversion.cc @@ -217,16 +217,12 @@ bool debVersioningSystem::CheckDep(const char *PkgVer, return false; Op &= 0x0F; - size_t const lenPkgVer = strlen(PkgVer); - size_t const lenDepVer = strlen(DepVer); - - // take a shortcut for equals which are string-equal as well - if (Op == pkgCache::Dep::Equals && lenPkgVer == lenDepVer && - memcmp(PkgVer, DepVer, lenPkgVer) == 0) - return true; + // fast track for (equal) strings [by location] which are by definition equal versions + if (PkgVer == DepVer) + return Op == pkgCache::Dep::Equals || Op == pkgCache::Dep::LessEq || Op == pkgCache::Dep::GreaterEq; // Perform the actual comparision. - int const Res = DoCmpVersion(PkgVer, PkgVer + lenPkgVer, DepVer, DepVer + lenDepVer); + int const Res = CmpVersion(PkgVer, DepVer); switch (Op) { case pkgCache::Dep::LessEq: diff --git a/apt-pkg/pkgcachegen.cc b/apt-pkg/pkgcachegen.cc index 8437dc68..3f10b6c4 100644 --- a/apt-pkg/pkgcachegen.cc +++ b/apt-pkg/pkgcachegen.cc @@ -390,7 +390,7 @@ bool pkgCacheGenerator::MergeListVersion(ListParser &List, pkgCache::PkgIterator } // Add a new version - map_ptrloc const verindex = NewVersion(Ver,Version,*LastVer); + map_ptrloc const verindex = NewVersion(Ver, Version, Pkg.Index(), Hash, *LastVer); if (verindex == 0 && _error->PendingError()) return _error->Error(_("Error occurred while processing %s (%s%d)"), Pkg.Name(), "NewVersion", 1); @@ -398,8 +398,6 @@ bool pkgCacheGenerator::MergeListVersion(ListParser &List, pkgCache::PkgIterator if (oldMap != Map.Data()) LastVer += (map_ptrloc*) Map.Data() - (map_ptrloc*) oldMap; *LastVer = verindex; - Ver->ParentPkg = Pkg.Index(); - Ver->Hash = Hash; if (unlikely(List.NewVersion(Ver) == false)) return _error->Error(_("Error occurred while processing %s (%s%d)"), @@ -557,7 +555,7 @@ bool pkgCacheGenerator::MergeFileProvides(ListParser &List) Dynamic DynVer(Ver); for (; Ver.end() == false; ++Ver) { - if (Ver->Hash == Hash && Version.c_str() == Ver.VerStr()) + if (Ver->Hash == Hash && Version == Ver.VerStr()) { if (List.CollectFileProvides(Cache,Ver) == false) return _error->Error(_("Error occurred while processing %s (%s%d)"), @@ -768,6 +766,8 @@ bool pkgCacheGenerator::NewFileVer(pkgCache::VerIterator &Ver, /* This puts a version structure in the linked list */ unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver, const string &VerStr, + map_ptrloc const ParentPkg, + unsigned long const Hash, unsigned long Next) { // Get a structure @@ -779,12 +779,37 @@ unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver, Ver = pkgCache::VerIterator(Cache,Cache.VerP + Version); //Dynamic DynV(Ver); // caller MergeListVersion already takes care of it Ver->NextVer = Next; + Ver->ParentPkg = ParentPkg; + Ver->Hash = Hash; Ver->ID = Cache.HeaderP->VersionCount++; + + // try to find the version string in the group for reuse + pkgCache::PkgIterator Pkg = Ver.ParentPkg(); + pkgCache::GrpIterator Grp = Pkg.Group(); + if (Pkg.end() == false && Grp.end() == false) + { + for (pkgCache::PkgIterator P = Grp.PackageList(); P.end() == false; P = Grp.NextPkg(P)) + { + if (Pkg == P) + continue; + for (pkgCache::VerIterator V = P.VersionList(); V.end() == false; ++V) + { + int const cmp = strcmp(V.VerStr(), VerStr.c_str()); + if (cmp == 0) + { + Ver->VerStr = V->VerStr; + return Version; + } + else if (cmp < 0) + break; + } + } + } + // haven't found the version string, so create map_ptrloc const idxVerStr = WriteStringInMap(VerStr); if (unlikely(idxVerStr == 0)) return 0; Ver->VerStr = idxVerStr; - return Version; } /*}}}*/ @@ -881,7 +906,7 @@ bool pkgCacheGenerator::NewDepends(pkgCache::PkgIterator &Pkg, index = WriteStringInMap(Version); if (unlikely(index == 0)) return false; - if (oldMap != Map.Data()) + if (OldDepLast != 0 && oldMap != Map.Data()) OldDepLast += (map_ptrloc*) Map.Data() - (map_ptrloc*) oldMap; } } diff --git a/apt-pkg/pkgcachegen.h b/apt-pkg/pkgcachegen.h index e759cbd3..428e8459 100644 --- a/apt-pkg/pkgcachegen.h +++ b/apt-pkg/pkgcachegen.h @@ -80,7 +80,11 @@ class pkgCacheGenerator /*{{{*/ bool NewDepends(pkgCache::PkgIterator &Pkg, pkgCache::VerIterator &Ver, map_ptrloc const Version, unsigned int const &Op, unsigned int const &Type, map_ptrloc* &OldDepLast); - unsigned long NewVersion(pkgCache::VerIterator &Ver,const std::string &VerStr,unsigned long Next); + __deprecated unsigned long NewVersion(pkgCache::VerIterator &Ver,const std::string &VerStr,unsigned long Next) + { return NewVersion(Ver, VerStr, 0, 0, Next); } + unsigned long NewVersion(pkgCache::VerIterator &Ver,const std::string &VerStr, + map_ptrloc const ParentPkg, unsigned long const Hash, + unsigned long Next); map_ptrloc NewDescription(pkgCache::DescIterator &Desc,const std::string &Lang,const MD5SumValue &md5sum,map_ptrloc Next); public: diff --git a/debian/changelog b/debian/changelog index 7070c5fc..9fce4b14 100644 --- a/debian/changelog +++ b/debian/changelog @@ -11,6 +11,8 @@ apt (0.9.7.8~exp2+nmu1) UNRELEASED; urgency=low - equal comparisions are used mostly in same-source relations, so use this to try to reuse some version strings - sort group and package names in the hashtable on insert + - share version strings between same versions (of different architectures) + to save some space and allow quick comparisions later on * apt-pkg/pkgcache.cc: - assume sorted hashtable entries for groups/packages * apt-pkg/cacheiterators.h: -- 2.20.1