]> git.saurik.com Git - apt.git/blobdiff - apt-pkg/packagemanager.cc
Merge remote-tracking branch 'mvo/feature/upgrade-with-cmdline' into debian/sid
[apt.git] / apt-pkg / packagemanager.cc
index 8b73b9980d39c08f08309def0311e8c2d8c99cd3..8c0d2e855667ee62f861729d9da21a3f242dec69 100644 (file)
@@ -13,6 +13,8 @@
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
+#include<config.h>
+
 #include <apt-pkg/packagemanager.h>
 #include <apt-pkg/orderlist.h>
 #include <apt-pkg/depcache.h>
 #include <apt-pkg/algorithms.h>
 #include <apt-pkg/configuration.h>
 #include <apt-pkg/sptr.h>
-    
-#include <apti18n.h>    
+
 #include <iostream>
-#include <fcntl.h> 
+#include <fcntl.h>
+
+#include <apti18n.h>
                                                                        /*}}}*/
 using namespace std;
 
+bool pkgPackageManager::SigINTStop = false;
+
 // PM::PackageManager - Constructor                                    /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-pkgPackageManager::pkgPackageManager(pkgDepCache *pCache) : Cache(*pCache)
+pkgPackageManager::pkgPackageManager(pkgDepCache *pCache) : Cache(*pCache),
+                                                           List(NULL), Res(Incomplete)
 {
    FileNames = new string[Cache.Head().PackageCount];
-   List = 0;
    Debug = _config->FindB("Debug::pkgPackageManager",false);
+   NoImmConfigure = !_config->FindB("APT::Immediate-Configure",true);
+   ImmConfigureAll = _config->FindB("APT::Immediate-Configure-All",false);
 }
                                                                        /*}}}*/
 // PM::PackageManager - Destructor                                     /*{{{*/
@@ -146,7 +153,7 @@ void pkgPackageManager::ImmediateAdd(PkgIterator I, bool UseInstallVer, unsigned
         if(!List->IsFlag(D.TargetPkg(), pkgOrderList::Immediate))
         {
            if(Debug)
-              clog << OutputInDepth(Depth) << "ImmediateAdd(): Adding Immediate flag to " << D.TargetPkg() << " cause of " << D.DepType() << " " << I.Name() << endl;
+              clog << OutputInDepth(Depth) << "ImmediateAdd(): Adding Immediate flag to " << D.TargetPkg() << " cause of " << D.DepType() << " " << I.FullName() << endl;
            List->Flag(D.TargetPkg(),pkgOrderList::Immediate);
            ImmediateAdd(D.TargetPkg(), UseInstallVer, Depth + 1);
         }
@@ -165,8 +172,9 @@ bool pkgPackageManager::CreateOrderList()
    
    delete List;
    List = new pkgOrderList(&Cache);
-   
-   static bool const NoImmConfigure = !_config->FindB("APT::Immediate-Configure",true);
+
+   if (Debug && ImmConfigureAll) 
+      clog << "CreateOrderList(): Adding Immediate flag for all packages because of APT::Immediate-Configure-All" << endl;
    
    // Generate the list of affected packages and sort it
    for (PkgIterator I = Cache.PkgBegin(); I.end() == false; ++I)
@@ -176,19 +184,20 @@ bool pkgPackageManager::CreateOrderList()
         continue;
       
       // Mark the package and its dependends for immediate configuration
-      if (((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential ||
-          (I->Flags & pkgCache::Flag::Important) == pkgCache::Flag::Important) &&
-         NoImmConfigure == false)
+      if ((((I->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential) &&
+         NoImmConfigure == false) || ImmConfigureAll)
       {
-        if(Debug)
-           clog << "CreateOrderList(): Adding Immediate flag for " << I.Name() << endl;
+        if(Debug && !ImmConfigureAll)
+           clog << "CreateOrderList(): Adding Immediate flag for " << I.FullName() << endl;
         List->Flag(I,pkgOrderList::Immediate);
-
-        // Look for other install packages to make immediate configurea
-        ImmediateAdd(I, true);
         
-        // And again with the current version.
-        ImmediateAdd(I, false);
+        if (!ImmConfigureAll) {
+           // Look for other install packages to make immediate configurea
+           ImmediateAdd(I, true);
+         
+           // And again with the current version.
+           ImmediateAdd(I, false);
+        }
       }
       
       // Not interesting
@@ -240,7 +249,7 @@ bool pkgPackageManager::CheckRConflicts(PkgIterator Pkg,DepIterator D,
         continue;
       
       // Ignore self conflicts, ignore conflicts from irrelevent versions
-      if (D.ParentPkg() == Pkg || D.ParentVer() != D.ParentPkg().CurrentVer())
+      if (D.IsIgnorable(Pkg) || D.ParentVer() != D.ParentPkg().CurrentVer())
         continue;
       
       if (Cache.VS().CheckDep(Ver,D->CompareOp,D.TargetVer()) == false)
@@ -248,7 +257,7 @@ bool pkgPackageManager::CheckRConflicts(PkgIterator Pkg,DepIterator D,
 
       if (EarlyRemove(D.ParentPkg()) == false)
         return _error->Error("Reverse conflicts early remove for package '%s' failed",
-                             Pkg.Name());
+                             Pkg.FullName().c_str());
    }
    return true;
 }
@@ -256,7 +265,8 @@ bool pkgPackageManager::CheckRConflicts(PkgIterator Pkg,DepIterator D,
 // PM::ConfigureAll - Run the all out configuration                    /*{{{*/
 // ---------------------------------------------------------------------
 /* This configures every package. It is assumed they are all unpacked and
-   that the final configuration is valid. */
+   that the final configuration is valid. This is also used to catch packages
+   that have not been configured when using ImmConfigureAll */
 bool pkgPackageManager::ConfigureAll()
 {
    pkgOrderList OList(&Cache);
@@ -277,9 +287,19 @@ bool pkgPackageManager::ConfigureAll()
    for (pkgOrderList::iterator I = OList.begin(); I != OList.end(); ++I)
    {
       PkgIterator Pkg(Cache,*I);
+      
+      /* Check if the package has been configured, this can happen if SmartConfigure
+         calls its self */ 
+      if (List->IsFlag(Pkg,pkgOrderList::Configured)) continue;
 
-      if (ConfigurePkgs == true && Configure(Pkg) == false)
+      if (ConfigurePkgs == true && SmartConfigure(Pkg, 0) == false) {
+         if (ImmConfigureAll)
+            _error->Error(_("Could not perform immediate configuration on '%s'. "
+                       "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),Pkg.FullName().c_str(),1);
+         else
+            _error->Error("Internal error, packages left unconfigured. %s",Pkg.FullName().c_str());
         return false;
+      }
       
       List->Flag(Pkg,pkgOrderList::Configured,pkgOrderList::States);
    }
@@ -289,132 +309,225 @@ bool pkgPackageManager::ConfigureAll()
                                                                        /*}}}*/
 // PM::SmartConfigure - Perform immediate configuration of the pkg     /*{{{*/
 // ---------------------------------------------------------------------
-/* This routine scheduals the configuration of the given package and all
-   of it's dependents. */
-bool pkgPackageManager::SmartConfigure(PkgIterator Pkg)
+/* This function tries to put the system in a state where Pkg can be configured.
+   This involves checking each of Pkg's dependanies and unpacking and 
+   configuring packages where needed. 
+   
+   Note on failure: This method can fail, without causing any problems. 
+   This can happen when using Immediate-Configure-All, SmartUnPack may call
+   SmartConfigure, it may fail because of a complex dependancy situation, but
+   a error will only be reported if ConfigureAll fails. This is why some of the
+   messages this function reports on failure (return false;) as just warnings
+   only shown when debuging*/
+bool pkgPackageManager::SmartConfigure(PkgIterator Pkg, int const Depth)
 {
-   if (Debug == true)
-      clog << "SmartConfigure " << Pkg.Name() << endl;
+   // If this is true, only check and correct and dependencies without the Loop flag
+   bool const PkgLoop = List->IsFlag(Pkg,pkgOrderList::Loop);
 
-   pkgOrderList OList(&Cache);
+   if (Debug) {
+      VerIterator InstallVer = VerIterator(Cache,Cache[Pkg].InstallVer);
+      clog << OutputInDepth(Depth) << "SmartConfigure " << Pkg.FullName() << " (" << InstallVer.VerStr() << ")";
+      if (PkgLoop)
+        clog << " (Only Correct Dependencies)";
+      clog << endl;
+   }
 
-   if (DepAdd(OList,Pkg) == false)
-      return false;
+   VerIterator const instVer = Cache[Pkg].InstVerIter(Cache);
+      
+   /* Because of the ordered list, most dependencies should be unpacked, 
+      however if there is a loop (A depends on B, B depends on A) this will not 
+      be the case, so check for dependencies before configuring. */
+   bool Bad = false, Changed = false;
+   const unsigned int max_loops = _config->FindI("APT::pkgPackageManager::MaxLoopCount", 5000);
+   unsigned int i=0;
+   std::list<DepIterator> needConfigure;
+   do
+   {
+      Changed = false;
+      for (DepIterator D = instVer.DependsList(); D.end() == false; )
+      {
+        // Compute a single dependency element (glob or)
+        pkgCache::DepIterator Start, End;
+        D.GlobOr(Start,End);
 
-   static std::string const conf = _config->Find("PackageManager::Configure","all");
-   static bool const ConfigurePkgs = (conf == "all" || conf == "smart");
+        if (End->Type != pkgCache::Dep::Depends)
+           continue;
+        Bad = true;
 
-   if (ConfigurePkgs == true)
-      if (OList.OrderConfigure() == false)
-        return false;
+        // Check for dependencies that have not been unpacked, probably due to loops.
+        for (DepIterator Cur = Start; true; ++Cur)
+        {
+           SPtrArray<Version *> VList = Cur.AllTargets();
 
-   // Perform the configuring
-   for (pkgOrderList::iterator I = OList.begin(); I != OList.end(); ++I)
-   {
-      PkgIterator Pkg(Cache,*I);
-      
-      if (ConfigurePkgs == true && Configure(Pkg) == false)
-        return false;
-      
-      List->Flag(Pkg,pkgOrderList::Configured,pkgOrderList::States);
-   }
+           for (Version **I = VList; *I != 0; ++I)
+           {
+              VerIterator Ver(Cache,*I);
+              PkgIterator DepPkg = Ver.ParentPkg();
 
-   if (Cache[Pkg].InstVerIter(Cache)->MultiArch == pkgCache::Version::Same)
-      for (PkgIterator P = Pkg.Group().PackageList();
-          P.end() == false; P = Pkg.Group().NextPkg(P))
-      {
-        if (Pkg == P || List->IsFlag(P,pkgOrderList::Configured) == true ||
-            Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
-             (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
-           continue;
-        SmartConfigure(P);
-      }
+              // Check if the current version of the package is available and will satisfy this dependency
+              if (DepPkg.CurrentVer() == Ver && List->IsNow(DepPkg) == true &&
+                  List->IsFlag(DepPkg,pkgOrderList::Removed) == false &&
+                  DepPkg.State() == PkgIterator::NeedsNothing)
+              {
+                 Bad = false;
+                 break;
+              }
 
-   // Sanity Check
-   if (List->IsFlag(Pkg,pkgOrderList::Configured) == false)
-      return _error->Error(_("Could not perform immediate configuration on '%s'. "
-                       "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),Pkg.Name(),1);
+              // Check if the version that is going to be installed will satisfy the dependency
+              if (Cache[DepPkg].InstallVer != *I || List->IsNow(DepPkg) == false)
+                 continue;
 
-   return true;
-}
-                                                                       /*}}}*/
-// PM::DepAdd - Add all dependents to the oder list                    /*{{{*/
-// ---------------------------------------------------------------------
-/* This recursively adds all dependents to the order list */
-bool pkgPackageManager::DepAdd(pkgOrderList &OList,PkgIterator Pkg,int Depth)
-{
-   if (OList.IsFlag(Pkg,pkgOrderList::Added) == true)
-      return true;
-   if (List->IsFlag(Pkg,pkgOrderList::Configured) == true)
-      return true;
-   if (List->IsFlag(Pkg,pkgOrderList::UnPacked) == false)
-      return false;
+              if (PkgLoop == true)
+              {
+                 if (Debug)
+                    std::clog << OutputInDepth(Depth) << "Package " << Pkg << " loops in SmartConfigure" << std::endl;
+                 Bad = false;
+                 break;
+              }
+              else
+              {
+                 if (Debug)
+                    clog << OutputInDepth(Depth) << "Unpacking " << DepPkg.FullName() << " to avoid loop " << Cur << endl;
+                 if (PkgLoop == false)
+                    List->Flag(Pkg,pkgOrderList::Loop);
+                 if (SmartUnPack(DepPkg, true, Depth + 1) == true)
+                 {
+                    Bad = false;
+                    if (List->IsFlag(DepPkg,pkgOrderList::Loop) == false)
+                       Changed = true;
+                 }
+                 if (PkgLoop == false)
+                    List->RmFlag(Pkg,pkgOrderList::Loop);
+                 if (Bad == false)
+                    break;
+              }
+           }
 
-   if (Debug) 
-      std::clog << OutputInDepth(Depth) << "DepAdd: " << Pkg.Name() << std::endl;
-      
-   // Put the package on the list
-   OList.push_back(Pkg);
-   OList.Flag(Pkg,pkgOrderList::Added);
-   Depth++;
+           if (Cur == End || Bad == false)
+              break;
+        }
 
-   // Check the dependencies to see if they are all satisfied.
-   bool Bad = false;
-   for (DepIterator D = Cache[Pkg].InstVerIter(Cache).DependsList(); D.end() == false;)
-   {
-      if (D->Type != pkgCache::Dep::Depends && D->Type != pkgCache::Dep::PreDepends)
-      {
-        ++D;
-        continue;
+        if (Bad == false)
+           continue;
+
+        needConfigure.push_back(Start);
       }
-      
-      // Grok or groups
-      Bad = true;
-      for (bool LastOR = true; D.end() == false && LastOR == true; ++D)
+      if (i++ > max_loops)
+         return _error->Error("Internal error: MaxLoopCount reached in SmartUnPack (1) for %s, aborting", Pkg.FullName().c_str());
+   } while (Changed == true);
+
+   Bad = false, Changed = false, i = 0;
+   do
+   {
+      Changed = false;
+      for (std::list<DepIterator>::const_iterator D = needConfigure.begin(); D != needConfigure.end(); ++D)
       {
-        LastOR = (D->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
-        
-        if (Bad == false)
+        // Compute a single dependency element (glob or) without modifying D
+        pkgCache::DepIterator Start, End;
+        {
+           pkgCache::DepIterator Discard = *D;
+           Discard.GlobOr(Start,End);
+        }
+
+        if (End->Type != pkgCache::Dep::Depends)
            continue;
+        Bad = true;
 
-        SPtrArray<Version *> VList = D.AllTargets();
-        for (Version **I = VList; *I != 0 && Bad == true; ++I)
+        // Search for dependencies which are unpacked but aren't configured yet (maybe loops)
+        for (DepIterator Cur = Start; true; ++Cur)
         {
-           VerIterator Ver(Cache,*I);
-           PkgIterator Pkg = Ver.ParentPkg();
+           SPtrArray<Version *> VList = Cur.AllTargets();
 
-           // See if the current version is ok
-           if (Pkg.CurrentVer() == Ver && List->IsNow(Pkg) == true && 
-               Pkg.State() == PkgIterator::NeedsNothing)
+           for (Version **I = VList; *I != 0; ++I)
            {
-              Bad = false;
-              continue;
+              VerIterator Ver(Cache,*I);
+              PkgIterator DepPkg = Ver.ParentPkg();
+
+              // Check if the version that is going to be installed will satisfy the dependency
+              if (Cache[DepPkg].InstallVer != *I)
+                 continue;
+
+              if (List->IsFlag(DepPkg,pkgOrderList::UnPacked))
+              {
+                 if (List->IsFlag(DepPkg,pkgOrderList::Loop) && PkgLoop)
+                 {
+                   // This dependency has already been dealt with by another SmartConfigure on Pkg
+                   Bad = false;
+                   break;
+                 }
+                 /* Check for a loop to prevent one forming
+                      If A depends on B and B depends on A, SmartConfigure will
+                      just hop between them if this is not checked. Dont remove the
+                      loop flag after finishing however as loop is already set.
+                      This means that there is another SmartConfigure call for this
+                      package and it will remove the loop flag */
+                 if (PkgLoop == false)
+                    List->Flag(Pkg,pkgOrderList::Loop);
+                 if (SmartConfigure(DepPkg, Depth + 1) == true)
+                 {
+                    Bad = false;
+                    if (List->IsFlag(DepPkg,pkgOrderList::Loop) == false)
+                       Changed = true;
+                 }
+                 if (PkgLoop == false)
+                   List->RmFlag(Pkg,pkgOrderList::Loop);
+                 // If SmartConfigure was succesfull, Bad is false, so break
+                 if (Bad == false)
+                    break;
+              }
+              else if (List->IsFlag(DepPkg,pkgOrderList::Configured))
+              {
+                 Bad = false;
+                 break;
+              }
            }
-           
-           // Not the install version 
-           if (Cache[Pkg].InstallVer != *I || 
-               (Cache[Pkg].Keep() == true && Pkg.State() == PkgIterator::NeedsNothing))
-              continue;
-           
-           if (List->IsFlag(Pkg,pkgOrderList::UnPacked) == true)
-              Bad = !DepAdd(OList,Pkg,Depth);
-           if (List->IsFlag(Pkg,pkgOrderList::Configured) == true)
-              Bad = false;
-        }
-      }
-      
-      if (Bad == true)
-      {
-        if (Debug) 
-           std::clog << OutputInDepth(Depth) << "DepAdd FAILS on: " << Pkg.Name() << std::endl;
-        OList.Flag(Pkg,0,pkgOrderList::Added);
-        OList.pop_back();
-        Depth--;
-        return false;
+           if (Cur == End || Bad == false)
+              break;
+         }
+
+
+        if (Bad == true && Changed == false && Debug == true)
+           std::clog << OutputInDepth(Depth) << "Could not satisfy " << *D << std::endl;
       }
+      if (i++ > max_loops)
+         return _error->Error("Internal error: MaxLoopCount reached in SmartUnPack (2) for %s, aborting", Pkg.FullName().c_str());
+   } while (Changed == true);
+   
+   if (Bad) {
+      if (Debug)
+         _error->Warning(_("Could not configure '%s'. "),Pkg.FullName().c_str());
+      return false;
    }
    
-   Depth--;
+   if (PkgLoop) return true;
+
+   static std::string const conf = _config->Find("PackageManager::Configure","all");
+   static bool const ConfigurePkgs = (conf == "all" || conf == "smart");
+
+   if (List->IsFlag(Pkg,pkgOrderList::Configured)) 
+      return _error->Error("Internal configure error on '%s'.", Pkg.FullName().c_str());
+
+   if (ConfigurePkgs == true && Configure(Pkg) == false)
+      return false;
+
+   List->Flag(Pkg,pkgOrderList::Configured,pkgOrderList::States);
+
+   if ((Cache[Pkg].InstVerIter(Cache)->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
+      for (PkgIterator P = Pkg.Group().PackageList();
+          P.end() == false; P = Pkg.Group().NextPkg(P))
+      {
+        if (Pkg == P || List->IsFlag(P,pkgOrderList::Configured) == true ||
+            List->IsFlag(P,pkgOrderList::UnPacked) == false ||
+            Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
+             (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
+           continue;
+        SmartConfigure(P, (Depth +1));
+      }
+
+   // Sanity Check
+   if (List->IsFlag(Pkg,pkgOrderList::Configured) == false)
+      return _error->Error(_("Could not configure '%s'. "),Pkg.FullName().c_str());
+
    return true;
 }
                                                                        /*}}}*/
@@ -436,7 +549,8 @@ bool pkgPackageManager::EarlyRemove(PkgIterator Pkg)
 
    // Essential packages get special treatment
    bool IsEssential = false;
-   if ((Pkg->Flags & pkgCache::Flag::Essential) != 0)
+   if ((Pkg->Flags & pkgCache::Flag::Essential) != 0 ||
+       (Pkg->Flags & pkgCache::Flag::Important) != 0)
       IsEssential = true;
 
    /* Check for packages that are the dependents of essential packages and 
@@ -446,7 +560,8 @@ bool pkgPackageManager::EarlyRemove(PkgIterator Pkg)
       for (DepIterator D = Pkg.RevDependsList(); D.end() == false &&
           IsEssential == false; ++D)
         if (D->Type == pkgCache::Dep::Depends || D->Type == pkgCache::Dep::PreDepends)
-           if ((D.ParentPkg()->Flags & pkgCache::Flag::Essential) != 0)
+           if ((D.ParentPkg()->Flags & pkgCache::Flag::Essential) != 0 ||
+               (D.ParentPkg()->Flags & pkgCache::Flag::Important) != 0)
               IsEssential = true;
    }
 
@@ -457,7 +572,7 @@ bool pkgPackageManager::EarlyRemove(PkgIterator Pkg)
                                "removing the essential package %s due to a "
                                "Conflicts/Pre-Depends loop. This is often bad, "
                                "but if you really want to do it, activate the "
-                               "APT::Force-LoopBreak option."),Pkg.Name());
+                               "APT::Force-LoopBreak option."),Pkg.FullName().c_str());
    }
    
    bool Res = SmartRemove(Pkg);
@@ -478,139 +593,299 @@ bool pkgPackageManager::SmartRemove(PkgIterator Pkg)
    List->Flag(Pkg,pkgOrderList::Configured,pkgOrderList::States);
 
    return Remove(Pkg,(Cache[Pkg].iFlags & pkgDepCache::Purge) == pkgDepCache::Purge);
-   return true;
 }
                                                                        /*}}}*/
 // PM::SmartUnPack - Install helper                                    /*{{{*/
 // ---------------------------------------------------------------------
-/* This performs the task of handling pre-depends. */
+/* This puts the system in a state where it can Unpack Pkg, if Pkg is allready
+   unpacked, or when it has been unpacked, if Immediate==true it configures it. */
 bool pkgPackageManager::SmartUnPack(PkgIterator Pkg)
 {
-   return SmartUnPack(Pkg, true);
+   return SmartUnPack(Pkg, true, 0);
 }
-bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate)
+bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate, int const Depth)
 {
-   // Check if it is already unpacked
-   if (Pkg.State() == pkgCache::PkgIterator::NeedsConfigure &&
-       Cache[Pkg].Keep() == true)
-   {
-      List->Flag(Pkg,pkgOrderList::UnPacked,pkgOrderList::States);
-      if (Immediate == true &&
-         List->IsFlag(Pkg,pkgOrderList::Immediate) == true)
-        if (SmartConfigure(Pkg) == false)
-           return _error->Error(_("Could not perform immediate configuration on already unpacked '%s'. "
-                       "Please see man 5 apt.conf under APT::Immediate-Configure for details."),Pkg.Name());
-      return true;
+   bool PkgLoop = List->IsFlag(Pkg,pkgOrderList::Loop);
+
+   if (Debug) {
+      clog << OutputInDepth(Depth) << "SmartUnPack " << Pkg.FullName();
+      VerIterator InstallVer = VerIterator(Cache,Cache[Pkg].InstallVer);
+      if (Pkg.CurrentVer() == 0)
+        clog << " (install version " << InstallVer.VerStr() << ")";
+      else
+        clog << " (replace version " << Pkg.CurrentVer().VerStr() << " with " << InstallVer.VerStr() << ")";
+      if (PkgLoop)
+        clog << " (Only Perform PreUnpack Checks)";
+      clog << endl;
    }
 
    VerIterator const instVer = Cache[Pkg].InstVerIter(Cache);
 
-   /* See if this packages install version has any predependencies
-      that are not met by 'now' packages. */
-   for (DepIterator D = instVer.DependsList();
-       D.end() == false; )
+   /* PreUnpack Checks: This loop checks and attempts to rectify and problems that would prevent the package being unpacked.
+      It addresses: PreDepends, Conflicts, Obsoletes and Breaks (DpkgBreaks). Any resolutions that do not require it should
+      avoid configuration (calling SmartUnpack with Immediate=true), this is because when unpacking some packages with
+      complex dependancy structures, trying to configure some packages while breaking the loops can complicate things .
+      This will be either dealt with if the package is configured as a dependency of Pkg (if and when Pkg is configured),
+      or by the ConfigureAll call at the end of the for loop in OrderInstall. */
+   bool Changed = false;
+   const unsigned int max_loops = _config->FindI("APT::pkgPackageManager::MaxLoopCount", 5000);
+   unsigned int i = 0;
+   do 
    {
-      // Compute a single dependency element (glob or)
-      pkgCache::DepIterator Start;
-      pkgCache::DepIterator End;
-      D.GlobOr(Start,End);
-      
-      while (End->Type == pkgCache::Dep::PreDepends)
+      Changed = false;
+      for (DepIterator D = instVer.DependsList(); D.end() == false; )
       {
-        if (Debug == true)
-           clog << "PreDepends order for " << Pkg.Name() << std::endl;
+        // Compute a single dependency element (glob or)
+        pkgCache::DepIterator Start, End;
+        D.GlobOr(Start,End);
 
-        // Look for possible ok targets.
-        SPtrArray<Version *> VList = Start.AllTargets();
-        bool Bad = true;
-        for (Version **I = VList; *I != 0 && Bad == true; I++)
-        {
-           VerIterator Ver(Cache,*I);
-           PkgIterator Pkg = Ver.ParentPkg();
-           
-           // See if the current version is ok
-           if (Pkg.CurrentVer() == Ver && List->IsNow(Pkg) == true && 
-               Pkg.State() == PkgIterator::NeedsNothing)
+        if (End->Type == pkgCache::Dep::PreDepends)
+         {
+           bool Bad = true;
+           if (Debug)
+              clog << OutputInDepth(Depth) << "PreDepends order for " << Pkg.FullName() << std::endl;
+
+           // Look for easy targets: packages that are already okay
+           for (DepIterator Cur = Start; Bad == true; ++Cur)
            {
-              Bad = false;
-              if (Debug == true)
-                 clog << "Found ok package " << Pkg.Name() << endl;
-              continue;
+              SPtrArray<Version *> VList = Cur.AllTargets();
+              for (Version **I = VList; *I != 0; ++I)
+              {
+                 VerIterator Ver(Cache,*I);
+                 PkgIterator Pkg = Ver.ParentPkg();
+
+                 // See if the current version is ok
+                 if (Pkg.CurrentVer() == Ver && List->IsNow(Pkg) == true &&
+                     Pkg.State() == PkgIterator::NeedsNothing)
+                 {
+                    Bad = false;
+                    if (Debug)
+                       clog << OutputInDepth(Depth) << "Found ok package " << Pkg.FullName() << endl;
+                    break;
+                 }
+              }
+              if (Cur == End)
+                 break;
            }
+
+           // Look for something that could be configured.
+           for (DepIterator Cur = Start; Bad == true && Cur.end() == false; ++Cur)
+           {
+              SPtrArray<Version *> VList = Cur.AllTargets();
+              for (Version **I = VList; *I != 0; ++I)
+              {
+                 VerIterator Ver(Cache,*I);
+                 PkgIterator Pkg = Ver.ParentPkg();
+
+                 // Not the install version
+                 if (Cache[Pkg].InstallVer != *I ||
+                     (Cache[Pkg].Keep() == true && Pkg.State() == PkgIterator::NeedsNothing))
+                    continue;
+
+                 if (List->IsFlag(Pkg,pkgOrderList::Configured))
+                 {
+                    Bad = false;
+                    break;
+                 }
+
+                 // check if it needs unpack or if if configure is enough
+                 if (List->IsFlag(Pkg,pkgOrderList::UnPacked) == false)
+                 {
+                    if (Debug)
+                       clog << OutputInDepth(Depth) << "Trying to SmartUnpack " << Pkg.FullName() << endl;
+                    // SmartUnpack with the ImmediateFlag to ensure its really ready
+                    if (SmartUnPack(Pkg, true, Depth + 1) == true)
+                    {
+                       Bad = false;
+                       if (List->IsFlag(Pkg,pkgOrderList::Loop) == false)
+                          Changed = true;
+                       break;
+                    }
+                 }
+                 else
+                 {
+                    if (Debug)
+                       clog << OutputInDepth(Depth) << "Trying to SmartConfigure " << Pkg.FullName() << endl;
+                    if (SmartConfigure(Pkg, Depth + 1) == true)
+                    {
+                       Bad = false;
+                       if (List->IsFlag(Pkg,pkgOrderList::Loop) == false)
+                          Changed = true;
+                       break;
+                    }
+                 }
+              }
+           }
+
+           if (Bad == true)
+           {
+              if (Start == End)
+                 return _error->Error("Couldn't configure pre-depend %s for %s, "
+                                       "probably a dependency cycle.",
+                                       End.TargetPkg().FullName().c_str(),Pkg.FullName().c_str());
+           }
+           else
+              continue;
         }
-        
-        // Look for something that could be configured.
-        for (Version **I = VList; *I != 0 && Bad == true; I++)
+        else if (End->Type == pkgCache::Dep::Conflicts ||
+                 End->Type == pkgCache::Dep::Obsoletes)
         {
-           VerIterator Ver(Cache,*I);
-           PkgIterator Pkg = Ver.ParentPkg();
-           
-           // Not the install version 
-           if (Cache[Pkg].InstallVer != *I || 
-               (Cache[Pkg].Keep() == true && Pkg.State() == PkgIterator::NeedsNothing))
-              continue;
+           /* Look for conflicts. Two packages that are both in the install
+              state cannot conflict so we don't check.. */
+           SPtrArray<Version *> VList = End.AllTargets();
+           for (Version **I = VList; *I != 0; I++)
+           {
+              VerIterator Ver(Cache,*I);
+              PkgIterator ConflictPkg = Ver.ParentPkg();
+              VerIterator InstallVer(Cache,Cache[ConflictPkg].InstallVer);
 
-           if (Debug == true)
-              clog << "Trying to SmartConfigure " << Pkg.Name() << endl;
-           Bad = !SmartConfigure(Pkg);
+              // See if the current version is conflicting
+              if (ConflictPkg.CurrentVer() == Ver && List->IsNow(ConflictPkg))
+              {
+                 clog << OutputInDepth(Depth) << Pkg.FullName() << " conflicts with " << ConflictPkg.FullName() << endl;
+                 /* If a loop is not present or has not yet been detected, attempt to unpack packages
+                    to resolve this conflict. If there is a loop present, remove packages to resolve this conflict */
+                 if (List->IsFlag(ConflictPkg,pkgOrderList::Loop) == false)
+                 {
+                    if (Cache[ConflictPkg].Keep() == 0 && Cache[ConflictPkg].InstallVer != 0)
+                    {
+                       if (Debug)
+                          clog << OutputInDepth(Depth) << OutputInDepth(Depth) << "Unpacking " << ConflictPkg.FullName() << " to prevent conflict" << endl;
+                       List->Flag(Pkg,pkgOrderList::Loop);
+                       if (SmartUnPack(ConflictPkg,false, Depth + 1) == true)
+                          if (List->IsFlag(ConflictPkg,pkgOrderList::Loop) == false)
+                             Changed = true;
+                       // Remove loop to allow it to be used later if needed
+                       List->RmFlag(Pkg,pkgOrderList::Loop);
+                    }
+                    else if (EarlyRemove(ConflictPkg) == false)
+                       return _error->Error("Internal Error, Could not early remove %s (1)",ConflictPkg.FullName().c_str());
+                 }
+                 else if (List->IsFlag(ConflictPkg,pkgOrderList::Removed) == false)
+                 {
+                    if (Debug)
+                       clog << OutputInDepth(Depth) << "Because of conficts knot, removing " << ConflictPkg.FullName() << " to conflict violation" << endl;
+                    if (EarlyRemove(ConflictPkg) == false)
+                       return _error->Error("Internal Error, Could not early remove %s (2)",ConflictPkg.FullName().c_str());
+                 }
+              }
+           }
         }
-
-        /* If this or element did not match then continue on to the
-           next or element until a matching element is found */
-        if (Bad == true)
+        else if (End->Type == pkgCache::Dep::DpkgBreaks)
         {
-           // This triggers if someone make a pre-depends/depend loop.
-           if (Start == End)
-              return _error->Error("Couldn't configure pre-depend %s for %s, "
-                                   "probably a dependency cycle.",
-                                   End.TargetPkg().Name(),Pkg.Name());
-           ++Start;
-        }
-        else
-           break;
-      }
-      
-      if (End->Type == pkgCache::Dep::Conflicts || 
-         End->Type == pkgCache::Dep::Obsoletes)
-      {
-        /* Look for conflicts. Two packages that are both in the install
-           state cannot conflict so we don't check.. */
-        SPtrArray<Version *> VList = End.AllTargets();
-        for (Version **I = VList; *I != 0; I++)
-        {
-           VerIterator Ver(Cache,*I);
-           PkgIterator Pkg = Ver.ParentPkg();
-           
-           // See if the current version is conflicting
-           if (Pkg.CurrentVer() == Ver && List->IsNow(Pkg) == true)
+           SPtrArray<Version *> VList = End.AllTargets();
+           for (Version **I = VList; *I != 0; ++I)
            {
-              if (EarlyRemove(Pkg) == false)
-                 return _error->Error("Internal Error, Could not early remove %s",Pkg.Name());
+              VerIterator Ver(Cache,*I);
+              PkgIterator BrokenPkg = Ver.ParentPkg();
+              if (BrokenPkg.CurrentVer() != Ver)
+              {
+                 if (Debug)
+                    std::clog << OutputInDepth(Depth) << "  Ignore not-installed version " << Ver.VerStr() << " of " << Pkg.FullName() << " for " << End << std::endl;
+                 continue;
+              }
+
+              // Check if it needs to be unpacked
+              if (List->IsFlag(BrokenPkg,pkgOrderList::InList) && Cache[BrokenPkg].Delete() == false &&
+                  List->IsNow(BrokenPkg))
+              {
+                 if (List->IsFlag(BrokenPkg,pkgOrderList::Loop) && PkgLoop)
+                 {
+                    // This dependancy has already been dealt with by another SmartUnPack on Pkg
+                    break;
+                 }
+                 else
+                 {
+                    // Found a break, so see if we can unpack the package to avoid it
+                    // but do not set loop if another SmartUnPack already deals with it
+                    // Also, avoid it if the package we would unpack pre-depends on this one
+                    VerIterator InstallVer(Cache,Cache[BrokenPkg].InstallVer);
+                    bool circle = false;
+                    for (pkgCache::DepIterator D = InstallVer.DependsList(); D.end() == false; ++D)
+                    {
+                       if (D->Type != pkgCache::Dep::PreDepends)
+                          continue;
+                       SPtrArray<Version *> VL = D.AllTargets();
+                       for (Version **I = VL; *I != 0; ++I)
+                       {
+                          VerIterator V(Cache,*I);
+                          PkgIterator P = V.ParentPkg();
+                          // we are checking for installation as an easy 'protection' against or-groups and (unchosen) providers
+                          if (P != Pkg || (P.CurrentVer() != V && Cache[P].InstallVer != V))
+                             continue;
+                          circle = true;
+                          break;
+                       }
+                       if (circle == true)
+                          break;
+                    }
+                    if (circle == true)
+                    {
+                       if (Debug)
+                          clog << OutputInDepth(Depth) << "  Avoiding " << End << " avoided as " << BrokenPkg.FullName() << " has a pre-depends on " << Pkg.FullName() << std::endl;
+                       continue;
+                    }
+                    else
+                    {
+                       if (Debug)
+                       {
+                          clog << OutputInDepth(Depth) << "  Unpacking " << BrokenPkg.FullName() << " to avoid " << End;
+                          if (PkgLoop == true)
+                             clog << " (Looping)";
+                          clog << std::endl;
+                       }
+                       if (PkgLoop == false)
+                          List->Flag(Pkg,pkgOrderList::Loop);
+                       if (SmartUnPack(BrokenPkg, false, Depth + 1) == true)
+                       {
+                          if (List->IsFlag(BrokenPkg,pkgOrderList::Loop) == false)
+                             Changed = true;
+                       }
+                       if (PkgLoop == false)
+                          List->RmFlag(Pkg,pkgOrderList::Loop);
+                    }
+                 }
+              }
+              // Check if a package needs to be removed
+              else if (Cache[BrokenPkg].Delete() == true && List->IsFlag(BrokenPkg,pkgOrderList::Configured) == false)
+              {
+                 if (Debug)
+                    clog << OutputInDepth(Depth) << "  Removing " << BrokenPkg.FullName() << " to avoid " << End << endl;
+                 SmartRemove(BrokenPkg);
+              }
            }
         }
       }
-   }
-
+      if (i++ > max_loops)
+         return _error->Error("Internal error: APT::pkgPackageManager::MaxLoopCount reached in SmartConfigure for %s, aborting", Pkg.FullName().c_str());
+   } while (Changed == true);
+   
    // Check for reverse conflicts.
    if (CheckRConflicts(Pkg,Pkg.RevDependsList(),
                   instVer.VerStr()) == false)
-      return false;
+                         return false;
    
    for (PrvIterator P = instVer.ProvidesList();
        P.end() == false; ++P)
       if (Pkg->Group != P.OwnerPkg()->Group)
         CheckRConflicts(Pkg,P.ParentPkg().RevDependsList(),P.ProvideVersion());
 
+   if (PkgLoop)
+      return true;
+
    List->Flag(Pkg,pkgOrderList::UnPacked,pkgOrderList::States);
 
-   if (Immediate == true && instVer->MultiArch == pkgCache::Version::Same)
+   if (Immediate == true && (instVer->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
    {
       /* Do lockstep M-A:same unpacking in two phases:
         First unpack all installed architectures, then the not installed.
         This way we avoid that M-A: enabled packages are installed before
         their older non-M-A enabled packages are replaced by newer versions */
       bool const installed = Pkg->CurrentVer != 0;
-      if (installed == true && Install(Pkg,FileNames[Pkg->ID]) == false)
+      if (installed == true &&
+         (instVer != Pkg.CurrentVer() ||
+          ((Cache[Pkg].iFlags & pkgDepCache::ReInstall) == pkgDepCache::ReInstall)) &&
+         Install(Pkg,FileNames[Pkg->ID]) == false)
         return false;
       for (PkgIterator P = Pkg.Group().PackageList();
           P.end() == false; P = Pkg.Group().NextPkg(P))
@@ -619,7 +894,7 @@ bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate)
             Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
              (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
            continue;
-        if (SmartUnPack(P, false) == false)
+        if (SmartUnPack(P, false, Depth + 1) == false)
            return false;
       }
       if (installed == false && Install(Pkg,FileNames[Pkg->ID]) == false)
@@ -628,22 +903,26 @@ bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate)
           P.end() == false; P = Pkg.Group().NextPkg(P))
       {
         if (P->CurrentVer != 0 || P == Pkg || List->IsFlag(P,pkgOrderList::UnPacked) == true ||
+            List->IsFlag(P,pkgOrderList::Configured) == true ||
             Cache[P].InstallVer == 0 || (P.CurrentVer() == Cache[P].InstallVer &&
              (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall))
            continue;
-        if (SmartUnPack(P, false) == false)
+        if (SmartUnPack(P, false, Depth + 1) == false)
            return false;
       }
    }
-   else if (Install(Pkg,FileNames[Pkg->ID]) == false)
+   // packages which are already unpacked don't need to be unpacked again
+   else if ((instVer != Pkg.CurrentVer() ||
+            ((Cache[Pkg].iFlags & pkgDepCache::ReInstall) == pkgDepCache::ReInstall)) &&
+           Install(Pkg,FileNames[Pkg->ID]) == false)
       return false;
 
-   // Perform immedate configuration of the package.
-   if (Immediate == true &&
-       List->IsFlag(Pkg,pkgOrderList::Immediate) == true)
-      if (SmartConfigure(Pkg) == false)
-        return _error->Error(_("Could not perform immediate configuration on '%s'. "
-                       "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),Pkg.Name(),2);
+   if (Immediate == true) {
+      // Perform immedate configuration of the package. 
+         if (SmartConfigure(Pkg, Depth + 1) == false)
+            _error->Warning(_("Could not perform immediate configuration on '%s'. "
+               "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),Pkg.FullName().c_str(),2);
+   }
    
    return true;
 }
@@ -677,18 +956,25 @@ pkgPackageManager::OrderResult pkgPackageManager::OrderInstall()
    for (pkgOrderList::iterator I = List->begin(); I != List->end(); ++I)
    {
       PkgIterator Pkg(Cache,*I);
-
+      
       if (List->IsNow(Pkg) == false)
       {
-        if (Debug == true)
-           clog << "Skipping already done " << Pkg.Name() << endl;
+         if (!List->IsFlag(Pkg,pkgOrderList::Configured) && !NoImmConfigure) {
+            if (SmartConfigure(Pkg, 0) == false && Debug)
+               _error->Warning("Internal Error, Could not configure %s",Pkg.FullName().c_str());
+            // FIXME: The above warning message might need changing
+         } else {
+           if (Debug == true)
+              clog << "Skipping already done " << Pkg.FullName() << endl;
+        }
         continue;
+        
       }
       
       if (List->IsMissing(Pkg) == true)
       {
         if (Debug == true)
-           clog << "Sequence completed at " << Pkg.Name() << endl;
+           clog << "Sequence completed at " << Pkg.FullName() << endl;
         if (DoneSomething == false)
         {
            _error->Error("Internal Error, ordering was unable to handle the media swap");
@@ -702,7 +988,7 @@ pkgPackageManager::OrderResult pkgPackageManager::OrderInstall()
          Pkg.State() == pkgCache::PkgIterator::NeedsNothing &&
          (Cache[Pkg].iFlags & pkgDepCache::ReInstall) != pkgDepCache::ReInstall)
       {
-        _error->Error("Internal Error, trying to manipulate a kept package (%s)",Pkg.Name());
+        _error->Error("Internal Error, trying to manipulate a kept package (%s)",Pkg.FullName().c_str());
         return Failed;
       }
       
@@ -713,9 +999,16 @@ pkgPackageManager::OrderResult pkgPackageManager::OrderInstall()
            return Failed;
       }
       else
-        if (SmartUnPack(Pkg) == false)
+        if (SmartUnPack(Pkg,List->IsFlag(Pkg,pkgOrderList::Immediate),0) == false)
            return Failed;
       DoneSomething = true;
+      
+      if (ImmConfigureAll) {
+         /* ConfigureAll here to pick up and packages left unconfigured becuase they were unpacked in the 
+            "PreUnpack Checks" section */
+         if (!ConfigureAll())
+            return Failed; 
+      }
    }
 
    // Final run through the configure phase
@@ -728,10 +1021,10 @@ pkgPackageManager::OrderResult pkgPackageManager::OrderInstall()
       if (List->IsFlag(*I,pkgOrderList::Configured) == false)
       {
         _error->Error("Internal error, packages left unconfigured. %s",
-                      PkgIterator(Cache,*I).Name());
+                      PkgIterator(Cache,*I).FullName().c_str());
         return Failed;
       }
-   }   
+   }
         
    return Completed;
 }
@@ -763,4 +1056,4 @@ pkgPackageManager::OrderResult pkgPackageManager::DoInstall(int statusFd)
    
    return DoInstallPostFork(statusFd);
 }
-                                                                       /*}}}*/
+                                                                       /*}}}*/