Adding upstream version 2.6.1.upstream/2.6.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 510 insertions, 0 deletions

diff --git a/apt-pkg/policy.cc b/apt-pkg/policy.cc
new file mode 100644
index 0000000..68b3f5e
--- /dev/null
+++ b/apt-pkg/policy.cc
@@ -0,0 +1,510 @@
+   // -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Package Version Policy implementation
+
+   This is just a really simple wrapper around pkgVersionMatch with
+   some added goodies to manage the list of things..
+
+   See man apt_preferences for what value means what.
+
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/cachefilter.h>
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/pkgcache.h>
+#include <apt-pkg/policy.h>
+#include <apt-pkg/string_view.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/tagfile-keys.h>
+#include <apt-pkg/tagfile.h>
+#include <apt-pkg/version.h>
+#include <apt-pkg/versionmatch.h>
+
+#include <iostream>
+#include <random>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <ctype.h>
+#include <stddef.h>
+#include <string.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+using namespace std;
+
+constexpr short NEVER_PIN = std::numeric_limits<short>::min();
+
+struct pkgPolicy::Private
+{
+   std::string machineID;
+};
+
+// Policy::Init - Startup and bind to a cache				/*{{{*/
+// ---------------------------------------------------------------------
+/* Set the defaults for operation. The default mode with no loaded policy
+   file matches the V0 policy engine. */
+pkgPolicy::pkgPolicy(pkgCache *Owner) : VerPins(nullptr),
+					PFPriority(nullptr), Cache(Owner), d(new Private)
+{
+   if (Owner == 0)
+      return;
+   PFPriority = new signed short[Owner->Head().PackageFileCount];
+   VerPins = new Pin[Owner->Head().VersionCount];
+
+   auto VersionCount = Owner->Head().VersionCount;
+   for (decltype(VersionCount) I = 0; I != VersionCount; ++I)
+      VerPins[I].Type = pkgVersionMatch::None;
+
+   // The config file has a master override.
+   string DefRel = _config->Find("APT::Default-Release");
+   if (DefRel.empty() == false)
+   {
+      bool found = false;
+      for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); ++F)
+      {
+	 if (pkgVersionMatch::ExpressionMatches(DefRel, F.Archive()) ||
+	     pkgVersionMatch::ExpressionMatches(DefRel, F.Codename()) ||
+	     pkgVersionMatch::ExpressionMatches(DefRel, F.Version()) ||
+	     (DefRel.length() > 2 && DefRel[1] == '='))
+	    found = true;
+      }
+      // "now" is our internal archive name for the status file,
+      // which we should accept even if we have no status file at the moment
+      if (not found && pkgVersionMatch::ExpressionMatches(DefRel, "now"))
+	 found = true;
+      if (not found)
+	 _error->Error(_("The value '%s' is invalid for APT::Default-Release as such a release is not available in the sources"), DefRel.c_str());
+      else
+	 CreatePin(pkgVersionMatch::Release,"",DefRel,990);
+   }
+   InitDefaults();
+
+   d->machineID = APT::Configuration::getMachineID();
+}
+									/*}}}*/
+// Policy::InitDefaults - Compute the default selections		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgPolicy::InitDefaults()
+{
+   // Initialize the priorities based on the status of the package file
+   for (pkgCache::PkgFileIterator I = Cache->FileBegin(); I != Cache->FileEnd(); ++I)
+   {
+      PFPriority[I->ID] = 500;
+      if (I.Flagged(pkgCache::Flag::NotSource))
+	 PFPriority[I->ID] = 100;
+      else if (I.Flagged(pkgCache::Flag::ButAutomaticUpgrades))
+	 PFPriority[I->ID] = 100;
+      else if (I.Flagged(pkgCache::Flag::NotAutomatic))
+	 PFPriority[I->ID] = 1;
+   }
+
+   // Apply the defaults..
+   std::unique_ptr<bool[]> Fixed(new bool[Cache->HeaderP->PackageFileCount]);
+   memset(Fixed.get(),0,sizeof(Fixed[0])*Cache->HeaderP->PackageFileCount);
+   StatusOverride = false;
+   for (vector<Pin>::const_iterator I = Defaults.begin(); I != Defaults.end(); ++I)
+   {
+      pkgVersionMatch Match(I->Data,I->Type);
+      for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); ++F)
+      {
+	 if ((Fixed[F->ID] == false || I->Priority == NEVER_PIN) && PFPriority[F->ID] != NEVER_PIN && Match.FileMatch(F) == true)
+	 {
+	    PFPriority[F->ID] = I->Priority;
+
+	    if (PFPriority[F->ID] >= 1000)
+	       StatusOverride = true;
+
+	    Fixed[F->ID] = true;
+	 }
+      }
+   }
+
+   if (_config->FindB("Debug::pkgPolicy",false) == true)
+      for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); ++F)
+	 std::clog << "Prio of " << F.FileName() << ' ' << PFPriority[F->ID] << std::endl;
+
+   return true;
+}
+									/*}}}*/
+// Policy::GetCandidateVer - Get the candidate install version		/*{{{*/
+// ---------------------------------------------------------------------
+/* Evaluate the package pins and the default list to determine what the
+   best package is. */
+pkgCache::VerIterator pkgPolicy::GetCandidateVer(pkgCache::PkgIterator const &Pkg)
+{
+   pkgCache::VerIterator cand;
+   pkgCache::VerIterator cur = Pkg.CurrentVer();
+   int candPriority = -1;
+   pkgVersioningSystem *vs = Cache->VS;
+
+   for (pkgCache::VerIterator ver = Pkg.VersionList(); ver.end() == false; ++ver) {
+      int priority = GetPriority(ver, true);
+
+      if (priority == 0 || priority <= candPriority)
+	 continue;
+
+      // TODO: Maybe optimize to not compare versions
+      if (!cur.end() && priority < 1000
+	  && (vs->CmpVersion(ver.VerStr(), cur.VerStr()) < 0))
+	 continue;
+
+      candPriority = priority;
+      cand = ver;
+   }
+
+   return cand;
+}
+									/*}}}*/
+// Policy::CreatePin - Create an entry in the pin table..		/*{{{*/
+// ---------------------------------------------------------------------
+/* For performance we have 3 tables, the default table, the main cache
+   table (hashed to the cache). A blank package name indicates the pin
+   belongs to the default table. Order of insertion matters here, the
+   earlier defaults override later ones. */
+void pkgPolicy::CreatePin(pkgVersionMatch::MatchType Type,string Name,
+			  string Data,signed short Priority)
+{
+   if (Name.empty() == true)
+   {
+      Pin *P = &*Defaults.insert(Defaults.end(),Pin());
+      P->Type = Type;
+      P->Priority = Priority;
+      P->Data = Data;
+      return;
+   }
+
+   bool IsSourcePin = APT::String::Startswith(Name, "src:");
+   if (IsSourcePin) {
+      Name = Name.substr(sizeof("src:") - 1);
+   }
+
+   size_t found = Name.rfind(':');
+   string Arch;
+   if (found != string::npos) {
+      Arch = Name.substr(found+1);
+      Name.erase(found);
+   }
+
+   // Allow pinning by wildcards - beware of package names looking like wildcards!
+   // TODO: Maybe we should always prefer specific pins over non-specific ones.
+   if ((Name[0] == '/' && Name[Name.length() - 1] == '/') || Name.find_first_of("*[?") != string::npos)
+   {
+      pkgVersionMatch match(Data, Type);
+      for (pkgCache::GrpIterator G = Cache->GrpBegin(); G.end() != true; ++G)
+	 if (Name != G.Name() && match.ExpressionMatches(Name, G.Name()))
+	 {
+	    auto NameToPinFor = IsSourcePin ? string("src:").append(G.Name()) : string(G.Name());
+	    if (Arch.empty() == false)
+	       CreatePin(Type, NameToPinFor.append(":").append(Arch), Data, Priority);
+	    else
+	       CreatePin(Type, NameToPinFor, Data, Priority);
+	 }
+      return;
+   }
+
+   // find the package (group) this pin applies to
+   pkgCache::GrpIterator Grp = Cache->FindGrp(Name);
+   bool matched = false;
+   if (Grp.end() == false)
+   {
+      std::string MatchingArch;
+      if (Arch.empty() == true)
+	 MatchingArch = Cache->NativeArch();
+      else
+	 MatchingArch = Arch;
+      APT::CacheFilter::PackageArchitectureMatchesSpecification pams(MatchingArch);
+
+      if (IsSourcePin) {
+	 for (pkgCache::VerIterator Ver = Grp.VersionsInSource(); not Ver.end(); Ver = Ver.NextInSource())
+	 {
+	    if (pams(Ver.ParentPkg().Arch()) == false)
+	       continue;
+
+	    PkgPin P(Ver.ParentPkg().FullName());
+	    P.Type = Type;
+	    P.Priority = Priority;
+	    P.Data = Data;
+	    // Find matching version(s) and copy the pin into it
+	    pkgVersionMatch Match(P.Data,P.Type);
+	    if (Match.VersionMatches(Ver)) {
+	       Pin *VP = VerPins + Ver->ID;
+	       if (VP->Type == pkgVersionMatch::None) {
+		  *VP = P;
+		   matched = true;
+	       }
+	    }
+	 }
+      } else {
+	 for (pkgCache::PkgIterator Pkg = Grp.PackageList(); Pkg.end() != true; Pkg = Grp.NextPkg(Pkg))
+	 {
+	    if (pams(Pkg.Arch()) == false)
+	       continue;
+
+	    PkgPin P(Pkg.FullName());
+	    P.Type = Type;
+	    P.Priority = Priority;
+	    P.Data = Data;
+
+	    // Find matching version(s) and copy the pin into it
+	    pkgVersionMatch Match(P.Data,P.Type);
+	    for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() != true; ++Ver)
+	    {
+	       if (Match.VersionMatches(Ver)) {
+		  Pin *VP = VerPins + Ver->ID;
+		  if (VP->Type == pkgVersionMatch::None) {
+		     *VP = P;
+		      matched = true;
+		  }
+	       }
+	    }
+	 }
+      }
+   }
+
+   if (matched == false)
+   {
+      PkgPin *P = &*Unmatched.insert(Unmatched.end(),PkgPin(Name));
+      if (Arch.empty() == false)
+	 P->Pkg.append(":").append(Arch);
+      P->Type = Type;
+      P->Priority = Priority;
+      P->Data = Data;
+      return;
+   }
+}
+									/*}}}*/
+// Policy::GetPriority - Get the priority of the package pin		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+// Returns true if this update is excluded by phasing.
+static inline bool ExcludePhased(std::string machineID, pkgCache::VerIterator const &Ver)
+{
+   if (Ver.PhasedUpdatePercentage() == 100)
+      return false;
+
+   // FIXME: We have migrated to a legacy implementation until LP: #1929082 is fixed
+   if (not _config->FindB("APT::Get::Phase-Policy", false))
+      return false;
+
+   // The order and fallbacks for the always/never checks come from update-manager and exist
+   // to preserve compatibility.
+   if (_config->FindB("APT::Get::Always-Include-Phased-Updates",
+		      _config->FindB("Update-Manager::Always-Include-Phased-Updates", false)))
+      return false;
+
+   if (_config->FindB("APT::Get::Never-Include-Phased-Updates",
+		      _config->FindB("Update-Manager::Never-Include-Phased-Updates", false)))
+      return true;
+
+   if (machineID.empty()			 // no machine-id
+       || getenv("SOURCE_DATE_EPOCH") != nullptr // reproducible build - always include
+       || APT::Configuration::isChroot())
+      return false;
+
+   std::string seedStr = std::string(Ver.SourcePkgName()) + "-" + Ver.SourceVerStr() + "-" + machineID;
+   std::seed_seq seed(seedStr.begin(), seedStr.end());
+   std::minstd_rand rand(seed);
+   std::uniform_int_distribution<unsigned int> dist(0, 100);
+
+   return dist(rand) > Ver.PhasedUpdatePercentage();
+}
+APT_PURE signed short pkgPolicy::GetPriority(pkgCache::VerIterator const &Ver, bool ConsiderFiles)
+{
+   auto ceiling = std::numeric_limits<signed int>::max();
+   if (ExcludePhased(d->machineID, Ver))
+      ceiling = 1;
+   if (VerPins[Ver->ID].Type != pkgVersionMatch::None)
+   {
+      // If all sources are never pins, the never pin wins.
+      if (VerPins[Ver->ID].Priority == NEVER_PIN)
+	 return NEVER_PIN;
+      for (pkgCache::VerFileIterator file = Ver.FileList(); file.end() == false; file++)
+	 if (GetPriority(file.File()) != NEVER_PIN)
+	    return std::min((int)VerPins[Ver->ID].Priority, ceiling);
+   }
+   if (!ConsiderFiles)
+      return std::min(0, ceiling);
+
+   // priorities are short ints, but we want to pick a value outside the valid range here
+   auto priority = std::numeric_limits<signed int>::min();
+   for (pkgCache::VerFileIterator file = Ver.FileList(); file.end() == false; file++)
+   {
+      /* If this is the status file, and the current version is not the
+         version in the status file (ie it is not installed, or somesuch)
+         then it is not a candidate for installation, ever. This weeds
+         out bogus entries that may be due to config-file states, or
+         other. */
+      if (file.File().Flagged(pkgCache::Flag::NotSource) && Ver.ParentPkg().CurrentVer() != Ver)
+	 priority = std::max<decltype(priority)>(priority, -1);
+      else
+	 priority = std::max<decltype(priority)>(priority, GetPriority(file.File()));
+   }
+
+   return std::min(priority == std::numeric_limits<decltype(priority)>::min() ? 0 : priority, ceiling);
+}
+APT_PURE signed short pkgPolicy::GetPriority(pkgCache::PkgFileIterator const &File)
+{
+   return PFPriority[File->ID];
+}
+									/*}}}*/
+// SetPriority - Directly set priority					/*{{{*/
+// ---------------------------------------------------------------------
+void pkgPolicy::SetPriority(pkgCache::VerIterator const &Ver, signed short Priority)
+{
+   Pin pin;
+   pin.Data = "pkgPolicy::SetPriority";
+   pin.Priority = Priority;
+   VerPins[Ver->ID] = pin;
+}
+void pkgPolicy::SetPriority(pkgCache::PkgFileIterator const &File, signed short Priority)
+{
+   PFPriority[File->ID] = Priority;
+}
+
+									/*}}}*/
+// ReadPinDir - Load the pin files from this dir into a Policy		/*{{{*/
+// ---------------------------------------------------------------------
+/* This will load each pin file in the given dir into a Policy. If the
+   given dir is empty the dir set in Dir::Etc::PreferencesParts is used.
+   Note also that this method will issue a warning if the dir does not
+   exists but it will return true in this case! */
+bool ReadPinDir(pkgPolicy &Plcy,string Dir)
+{
+   if (Dir.empty() == true)
+      Dir = _config->FindDir("Dir::Etc::PreferencesParts", "/dev/null");
+
+   if (DirectoryExists(Dir) == false)
+   {
+      if (APT::String::Endswith(Dir, "/dev/null") == false)
+	 _error->WarningE("DirectoryExists",_("Unable to read %s"),Dir.c_str());
+      return true;
+   }
+
+   _error->PushToStack();
+   vector<string> const List = GetListOfFilesInDir(Dir, "pref", true, true);
+   bool const PendingErrors = _error->PendingError();
+   _error->MergeWithStack();
+   if (PendingErrors)
+      return false;
+
+   // Read the files
+   bool good = true;
+   for (vector<string>::const_iterator I = List.begin(); I != List.end(); ++I)
+      good = ReadPinFile(Plcy, *I) && good;
+   return good;
+}
+									/*}}}*/
+// ReadPinFile - Load the pin file into a Policy			/*{{{*/
+// ---------------------------------------------------------------------
+/* I'd like to see the preferences file store more than just pin information
+   but right now that is the only stuff I have to store. Later there will
+   have to be some kind of combined super parser to get the data into all
+   the right classes.. */
+bool ReadPinFile(pkgPolicy &Plcy,string File)
+{
+   if (File.empty() == true)
+      File = _config->FindFile("Dir::Etc::Preferences");
+
+   if (RealFileExists(File) == false)
+      return true;
+
+   FileFd Fd;
+   if (OpenConfigurationFileFd(File, Fd) == false)
+      return false;
+
+   pkgTagFile TF(&Fd, pkgTagFile::SUPPORT_COMMENTS);
+   if (Fd.IsOpen() == false || Fd.Failed())
+      return false;
+
+   pkgTagSection Tags;
+   while (TF.Step(Tags) == true)
+   {
+      // can happen when there are only comments in a record
+      if (Tags.Count() == 0)
+         continue;
+
+      auto Name = Tags.Find(pkgTagSection::Key::Package);
+      if (Name.empty())
+	 return _error->Error(_("Invalid record in the preferences file %s, no Package header"), File.c_str());
+      if (Name == "*")
+	 Name = APT::StringView{};
+
+      const char *Start;
+      const char *End;
+      if (Tags.Find("Pin",Start,End) == false)
+	 continue;
+	 
+      const char *Word = Start;
+      for (; Word != End && isspace(*Word) == 0; Word++);
+
+      // Parse the type..
+      pkgVersionMatch::MatchType Type;
+      if (stringcasecmp(Start,Word,"version") == 0 && Name.empty() == false)
+	 Type = pkgVersionMatch::Version;
+      else if (stringcasecmp(Start,Word,"release") == 0)
+	 Type = pkgVersionMatch::Release;
+      else if (stringcasecmp(Start,Word,"origin") == 0)
+	 Type = pkgVersionMatch::Origin;
+      else
+      {
+	 _error->Warning(_("Did not understand pin type %s"),string(Start,Word).c_str());
+	 continue;
+      }
+      for (; Word != End && isspace(*Word) != 0; Word++);
+
+      _error->PushToStack();
+      std::string sPriority = Tags.FindS("Pin-Priority");
+      int priority = sPriority == "never" ? NEVER_PIN : Tags.FindI("Pin-Priority", 0);
+      bool const newError = _error->PendingError();
+      _error->MergeWithStack();
+
+      if (sPriority == "never" && not Name.empty())
+	 return _error->Error(_("%s: The special 'Pin-Priority: %s' can only be used for 'Package: *' records"), File.c_str(), "never");
+
+      // Silently clamp the never pin to never pin + 1
+      if (priority == NEVER_PIN && sPriority != "never")
+	 priority = NEVER_PIN + 1;
+      if (priority < std::numeric_limits<short>::min() ||
+          priority > std::numeric_limits<short>::max() ||
+	  newError) {
+	 return _error->Error(_("%s: Value %s is outside the range of valid pin priorities (%d to %d)"),
+			      File.c_str(), Tags.FindS("Pin-Priority").c_str(),
+			      std::numeric_limits<short>::min(),
+			      std::numeric_limits<short>::max());
+      }
+      if (priority == 0)
+      {
+         return _error->Error(_("No priority (or zero) specified for pin"));
+      }
+
+      std::istringstream s(Name.to_string());
+      string pkg;
+      while(!s.eof())
+      {
+	 s >> pkg;
+         Plcy.CreatePin(Type, pkg, string(Word,End),priority);
+      };
+   }
+
+   Plcy.InitDefaults();
+   return true;
+}
+									/*}}}*/
+
+pkgPolicy::~pkgPolicy()
+{
+   delete[] PFPriority;
+   delete[] VerPins;
+   delete d;
+}