improve umask/fchmod code readability
[ntk/apt.git] / apt-pkg / edsp.cc
index 55bc0a0..ee42267 100644 (file)
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
+#include <config.h>
+
 #include <apt-pkg/edsp.h>
 #include <apt-pkg/error.h>
+#include <apt-pkg/cacheset.h>
 #include <apt-pkg/configuration.h>
-#include <apt-pkg/version.h>
-#include <apt-pkg/policy.h>
 #include <apt-pkg/tagfile.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/progress.h>
+#include <apt-pkg/depcache.h>
+#include <apt-pkg/pkgcache.h>
+#include <apt-pkg/cacheiterators.h>
+#include <apt-pkg/strutl.h>
 
-#include <apti18n.h>
+#include <ctype.h>
+#include <stddef.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <iostream>
+#include <vector>
 #include <limits>
+#include <string>
+#include <list>
 
-#include <stdio.h>
+#include <apti18n.h>
                                                                        /*}}}*/
 
+using std::string;
+
+// we could use pkgCache::DepType and ::Priority, but these would be localized strings…
+const char * const EDSP::PrioMap[] = {0, "important", "required", "standard",
+                                     "optional", "extra"};
+const char * const EDSP::DepMap[] = {"", "Depends", "Pre-Depends", "Suggests",
+                                    "Recommends" , "Conflicts", "Replaces",
+                                    "Obsoletes", "Breaks", "Enhances"};
+
 // EDSP::WriteScenario - to the given file descriptor                  /*{{{*/
-bool EDSP::WriteScenario(pkgDepCache &Cache, FILE* output)
+bool EDSP::WriteScenario(pkgDepCache &Cache, FILE* output, OpProgress *Progress)
 {
-   // we could use pkgCache::DepType and ::Priority, but these would be lokalized strings…
-   const char * const PrioMap[] = {0, "important", "required", "standard",
-                                  "optional", "extra"};
-   const char * const DepMap[] = {"", "Depends", "PreDepends", "Suggests",
-                                 "Recommends" , "Conflicts", "Replaces",
-                                 "Obsoletes", "Breaks", "Enhances"};
-
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().VersionCount, _("Send scenario to solver"));
+   unsigned long p = 0;
    for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
-   {
+      for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() == false; ++Ver, ++p)
+      {
+        WriteScenarioVersion(Cache, output, Pkg, Ver);
+        WriteScenarioDependency(output, Ver);
+        fprintf(output, "\n");
+        if (Progress != NULL && p % 100 == 0)
+           Progress->Progress(p);
+      }
+   return true;
+}
+                                                                       /*}}}*/
+// EDSP::WriteLimitedScenario - to the given file descriptor           /*{{{*/
+bool EDSP::WriteLimitedScenario(pkgDepCache &Cache, FILE* output,
+                               APT::PackageSet const &pkgset,
+                               OpProgress *Progress)
+{
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().VersionCount, _("Send scenario to solver"));
+   unsigned long p  = 0;
+   for (APT::PackageSet::const_iterator Pkg = pkgset.begin(); Pkg != pkgset.end(); ++Pkg, ++p)
       for (pkgCache::VerIterator Ver = Pkg.VersionList(); Ver.end() == false; ++Ver)
       {
-        fprintf(output, "Package: %s\n", Pkg.Name());
-        fprintf(output, "Architecture: %s\n", Ver.Arch());
-        fprintf(output, "Version: %s\n", Ver.VerStr());
-        if (Pkg.CurrentVer() == Ver)
-           fprintf(output, "Installed: yes\n");
-        if (Pkg->SelectedState == pkgCache::State::Hold)
-           fprintf(output, "Hold: yes\n");
-        fprintf(output, "APT-ID: %d\n", Ver->ID);
-        fprintf(output, "Priority: %s\n", PrioMap[Ver->Priority]);
-        if ((Pkg->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
-           fprintf(output, "Essential: yes\n");
-        fprintf(output, "Section: %s\n", Ver.Section());
-        if (Ver->MultiArch == pkgCache::Version::Allowed || Ver->MultiArch == pkgCache::Version::AllAllowed)
-           fprintf(output, "Multi-Arch: allowed\n");
-        else if (Ver->MultiArch == pkgCache::Version::Foreign || Ver->MultiArch == pkgCache::Version::AllForeign)
-           fprintf(output, "Multi-Arch: foreign\n");
-        else if (Ver->MultiArch == pkgCache::Version::Same)
-           fprintf(output, "Multi-Arch: same\n");
-        signed short Pin = std::numeric_limits<signed short>::min();
-        for (pkgCache::VerFileIterator File = Ver.FileList(); File.end() == false; ++File) {
-           signed short const p = Cache.GetPolicy().GetPriority(File.File());
-           if (Pin < p)
-              Pin = p;
-        }
-        fprintf(output, "APT-Pin: %d\n", Pin);
-        if (Cache.GetCandidateVer(Pkg) == Ver)
-           fprintf(output, "APT-Candidate: yes\n");
-        if ((Cache[Pkg].Flags & pkgCache::Flag::Auto) == pkgCache::Flag::Auto)
-           fprintf(output, "APT-Automatic: yes\n");
-        std::string dependencies[pkgCache::Dep::Enhances + 1];
-        bool orGroup = false;
-        for (pkgCache::DepIterator Dep = Ver.DependsList(); Dep.end() == false; ++Dep)
-        {
-           // Ignore implicit dependencies for multiarch here
-           if (strcmp(Pkg.Arch(), Dep.TargetPkg().Arch()) != 0)
-              continue;
-           if (orGroup == false)
-              dependencies[Dep->Type].append(", ");
-           dependencies[Dep->Type].append(Dep.TargetPkg().Name());
-           if (Dep->Version != 0)
-              dependencies[Dep->Type].append(" (").append(pkgCache::CompTypeDeb(Dep->CompareOp)).append(" ").append(Dep.TargetVer()).append(")");
-           if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
-           {
-              dependencies[Dep->Type].append(" | ");
-              orGroup = true;
-           }
-           else
-              orGroup = false;
-        }
-        for (int i = 1; i < pkgCache::Dep::Enhances + 1; ++i)
-           if (dependencies[i].empty() == false)
-              fprintf(output, "%s: %s\n", DepMap[i], dependencies[i].c_str()+2);
-        string provides;
-        for (pkgCache::PrvIterator Prv = Ver.ProvidesList(); Prv.end() == false; ++Prv)
-        {
-           // Ignore implicit provides for multiarch here
-           if (strcmp(Pkg.Arch(), Prv.ParentPkg().Arch()) != 0 || strcmp(Pkg.Name(),Prv.Name()) == 0)
-              continue;
-           provides.append(", ").append(Prv.Name());
-        }
-        if (provides.empty() == false)
-           fprintf(output, "Provides: %s\n", provides.c_str()+2);
-
-
+        WriteScenarioVersion(Cache, output, Pkg, Ver);
+        WriteScenarioLimitedDependency(output, Ver, pkgset);
         fprintf(output, "\n");
+        if (Progress != NULL && p % 100 == 0)
+           Progress->Progress(p);
       }
-   }
+   if (Progress != NULL)
+      Progress->Done();
    return true;
 }
                                                                        /*}}}*/
+// EDSP::WriteScenarioVersion                                          /*{{{*/
+void EDSP::WriteScenarioVersion(pkgDepCache &Cache, FILE* output, pkgCache::PkgIterator const &Pkg,
+                               pkgCache::VerIterator const &Ver)
+{
+   fprintf(output, "Package: %s\n", Pkg.Name());
+   fprintf(output, "Architecture: %s\n", Ver.Arch());
+   fprintf(output, "Version: %s\n", Ver.VerStr());
+   if (Pkg.CurrentVer() == Ver)
+      fprintf(output, "Installed: yes\n");
+   if (Pkg->SelectedState == pkgCache::State::Hold ||
+       (Cache[Pkg].Keep() == true && Cache[Pkg].Protect() == true))
+      fprintf(output, "Hold: yes\n");
+   fprintf(output, "APT-ID: %d\n", Ver->ID);
+   fprintf(output, "Priority: %s\n", PrioMap[Ver->Priority]);
+   if ((Pkg->Flags & pkgCache::Flag::Essential) == pkgCache::Flag::Essential)
+      fprintf(output, "Essential: yes\n");
+   fprintf(output, "Section: %s\n", Ver.Section());
+   if ((Ver->MultiArch & pkgCache::Version::Allowed) == pkgCache::Version::Allowed)
+      fprintf(output, "Multi-Arch: allowed\n");
+   else if ((Ver->MultiArch & pkgCache::Version::Foreign) == pkgCache::Version::Foreign)
+      fprintf(output, "Multi-Arch: foreign\n");
+   else if ((Ver->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
+      fprintf(output, "Multi-Arch: same\n");
+   signed short Pin = std::numeric_limits<signed short>::min();
+   for (pkgCache::VerFileIterator File = Ver.FileList(); File.end() == false; ++File) {
+      signed short const p = Cache.GetPolicy().GetPriority(File.File());
+      if (Pin < p)
+        Pin = p;
+   }
+   fprintf(output, "APT-Pin: %d\n", Pin);
+   if (Cache.GetCandidateVer(Pkg) == Ver)
+      fprintf(output, "APT-Candidate: yes\n");
+   if ((Cache[Pkg].Flags & pkgCache::Flag::Auto) == pkgCache::Flag::Auto)
+      fprintf(output, "APT-Automatic: yes\n");
+}
+                                                                       /*}}}*/
+// EDSP::WriteScenarioDependency                                       /*{{{*/
+void EDSP::WriteScenarioDependency( FILE* output, pkgCache::VerIterator const &Ver)
+{
+   std::string dependencies[pkgCache::Dep::Enhances + 1];
+   bool orGroup = false;
+   for (pkgCache::DepIterator Dep = Ver.DependsList(); Dep.end() == false; ++Dep)
+   {
+      if (Dep.IsMultiArchImplicit() == true)
+        continue;
+      if (orGroup == false)
+        dependencies[Dep->Type].append(", ");
+      dependencies[Dep->Type].append(Dep.TargetPkg().Name());
+      if (Dep->Version != 0)
+        dependencies[Dep->Type].append(" (").append(pkgCache::CompTypeDeb(Dep->CompareOp)).append(" ").append(Dep.TargetVer()).append(")");
+      if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+      {
+        dependencies[Dep->Type].append(" | ");
+        orGroup = true;
+      }
+      else
+        orGroup = false;
+   }
+   for (int i = 1; i < pkgCache::Dep::Enhances + 1; ++i)
+      if (dependencies[i].empty() == false)
+        fprintf(output, "%s: %s\n", DepMap[i], dependencies[i].c_str()+2);
+   string provides;
+   for (pkgCache::PrvIterator Prv = Ver.ProvidesList(); Prv.end() == false; ++Prv)
+   {
+      if (Prv.IsMultiArchImplicit() == true)
+        continue;
+      provides.append(", ").append(Prv.Name());
+   }
+   if (provides.empty() == false)
+      fprintf(output, "Provides: %s\n", provides.c_str()+2);
+}
+                                                                       /*}}}*/
+// EDSP::WriteScenarioLimitedDependency                                        /*{{{*/
+void EDSP::WriteScenarioLimitedDependency(FILE* output,
+                                         pkgCache::VerIterator const &Ver,
+                                         APT::PackageSet const &pkgset)
+{
+   std::string dependencies[pkgCache::Dep::Enhances + 1];
+   bool orGroup = false;
+   for (pkgCache::DepIterator Dep = Ver.DependsList(); Dep.end() == false; ++Dep)
+   {
+      if (Dep.IsMultiArchImplicit() == true)
+        continue;
+      if (orGroup == false)
+      {
+        if (pkgset.find(Dep.TargetPkg()) == pkgset.end())
+           continue;
+        dependencies[Dep->Type].append(", ");
+      }
+      else if (pkgset.find(Dep.TargetPkg()) == pkgset.end())
+      {
+        if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+           continue;
+        dependencies[Dep->Type].erase(dependencies[Dep->Type].end()-3, dependencies[Dep->Type].end());
+        orGroup = false;
+        continue;
+      }
+      dependencies[Dep->Type].append(Dep.TargetPkg().Name());
+      if (Dep->Version != 0)
+        dependencies[Dep->Type].append(" (").append(pkgCache::CompTypeDeb(Dep->CompareOp)).append(" ").append(Dep.TargetVer()).append(")");
+      if ((Dep->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or)
+      {
+        dependencies[Dep->Type].append(" | ");
+        orGroup = true;
+      }
+      else
+        orGroup = false;
+   }
+   for (int i = 1; i < pkgCache::Dep::Enhances + 1; ++i)
+      if (dependencies[i].empty() == false)
+        fprintf(output, "%s: %s\n", DepMap[i], dependencies[i].c_str()+2);
+   string provides;
+   for (pkgCache::PrvIterator Prv = Ver.ProvidesList(); Prv.end() == false; ++Prv)
+   {
+      if (Prv.IsMultiArchImplicit() == true)
+        continue;
+      if (pkgset.find(Prv.ParentPkg()) == pkgset.end())
+        continue;
+      provides.append(", ").append(Prv.Name());
+   }
+   if (provides.empty() == false)
+      fprintf(output, "Provides: %s\n", provides.c_str()+2);
+}
+                                                                       /*}}}*/
 // EDSP::WriteRequest - to the given file descriptor                   /*{{{*/
 bool EDSP::WriteRequest(pkgDepCache &Cache, FILE* output, bool const Upgrade,
-                       bool const DistUpgrade, bool const AutoRemove)
+                       bool const DistUpgrade, bool const AutoRemove,
+                       OpProgress *Progress)
 {
+   if (Progress != NULL)
+      Progress->SubProgress(Cache.Head().PackageCount, _("Send request to solver"));
+   unsigned long p = 0;
    string del, inst;
-   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
+   for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg, ++p)
    {
+      if (Progress != NULL && p % 100 == 0)
+         Progress->Progress(p);
       string* req;
-      if (Cache[Pkg].Delete() == true)
+      pkgDepCache::StateCache &P = Cache[Pkg];
+      if (P.Delete() == true)
         req = &del;
-      else if (Cache[Pkg].NewInstall() == true || Cache[Pkg].Upgrade() == true)
+      else if (P.NewInstall() == true || P.Upgrade() == true || P.ReInstall() == true ||
+              (P.Mode == pkgDepCache::ModeKeep && (P.iFlags & pkgDepCache::Protected) == pkgDepCache::Protected))
         req = &inst;
       else
         continue;
       req->append(" ").append(Pkg.FullName());
    }
-   fprintf(output, "Request: EDSP 0.2\n");
+   fprintf(output, "Request: EDSP 0.4\n");
    if (del.empty() == false)
       fprintf(output, "Remove: %s\n", del.c_str()+1);
    if (inst.empty() == false)
@@ -132,7 +245,7 @@ bool EDSP::WriteRequest(pkgDepCache &Cache, FILE* output, bool const Upgrade,
    if (_config->FindB("APT::Solver::Strict-Pinning", true) == false)
       fprintf(output, "Strict-Pinning: no\n");
    string solverpref("APT::Solver::");
-   solverpref.append(_config->Find("APT::Solver::Name", "internal")).append("::Preferences");
+   solverpref.append(_config->Find("APT::Solver", "internal")).append("::Preferences");
    if (_config->Exists(solverpref) == true)
       fprintf(output, "Preferences: %s\n", _config->Find(solverpref,"").c_str());
    fprintf(output, "\n");
@@ -141,21 +254,24 @@ bool EDSP::WriteRequest(pkgDepCache &Cache, FILE* output, bool const Upgrade,
 }
                                                                        /*}}}*/
 // EDSP::ReadResponse - from the given file descriptor                 /*{{{*/
-bool EDSP::ReadResponse(int const input, pkgDepCache &Cache) {
-       FileFd in;
-       in.OpenDescriptor(input, FileFd::ReadOnly);
-       pkgTagFile response(&in);
-       pkgTagSection section;
-
+bool EDSP::ReadResponse(int const input, pkgDepCache &Cache, OpProgress *Progress) {
        /* We build an map id to mmap offset here
           In theory we could use the offset as ID, but then VersionCount
           couldn't be used to create other versionmappings anymore and it
           would be too easy for a (buggy) solver to segfault APT… */
        unsigned long long const VersionCount = Cache.Head().VersionCount;
        unsigned long VerIdx[VersionCount];
-       for (pkgCache::PkgIterator P = Cache.PkgBegin(); P.end() == false; ++P)
+       for (pkgCache::PkgIterator P = Cache.PkgBegin(); P.end() == false; ++P) {
                for (pkgCache::VerIterator V = P.VersionList(); V.end() == false; ++V)
                        VerIdx[V->ID] = V.Index();
+               Cache[P].Marked = true;
+               Cache[P].Garbage = false;
+       }
+
+       FileFd in;
+       in.OpenDescriptor(input, FileFd::ReadOnly);
+       pkgTagFile response(&in, 100);
+       pkgTagSection section;
 
        while (response.Step(section) == true) {
                std::string type;
@@ -163,7 +279,29 @@ bool EDSP::ReadResponse(int const input, pkgDepCache &Cache) {
                        type = "Install";
                else if (section.Exists("Remove") == true)
                        type = "Remove";
-               //FIXME: handle progress
+               else if (section.Exists("Progress") == true) {
+                       if (Progress != NULL) {
+                               string msg = section.FindS("Message");
+                               if (msg.empty() == true)
+                                       msg = _("Prepare for receiving solution");
+                               Progress->SubProgress(100, msg, section.FindI("Percentage", 0));
+                       }
+                       continue;
+               } else if (section.Exists("Error") == true) {
+                       std::string msg = SubstVar(SubstVar(section.FindS("Message"), "\n .\n", "\n\n"), "\n ", "\n");
+                       if (msg.empty() == true) {
+                               msg = _("External solver failed without a proper error message");
+                               _error->Error("%s", msg.c_str());
+                       } else
+                               _error->Error("External solver failed with: %s", msg.substr(0,msg.find('\n')).c_str());
+                       if (Progress != NULL)
+                               Progress->Done();
+                       std::cerr << "The solver encountered an error of type: " << section.FindS("Error") << std::endl;
+                       std::cerr << "The following information might help you to understand what is wrong:" << std::endl;
+                       std::cerr << msg << std::endl << std::endl;
+                       return false;
+               } else if (section.Exists("Autoremove") == true)
+                       type = "Autoremove";
                else
                        continue;
 
@@ -179,9 +317,13 @@ bool EDSP::ReadResponse(int const input, pkgDepCache &Cache) {
                pkgCache::VerIterator Ver(Cache.GetCache(), Cache.GetCache().VerP + VerIdx[id]);
                Cache.SetCandidateVersion(Ver);
                if (type == "Install")
-                       Cache.MarkInstall(Ver.ParentPkg(), false, false);
+                       Cache.MarkInstall(Ver.ParentPkg(), false, 0, false);
                else if (type == "Remove")
                        Cache.MarkDelete(Ver.ParentPkg(), false);
+               else if (type == "Autoremove") {
+                       Cache[Ver.ParentPkg()].Marked = false;
+                       Cache[Ver.ParentPkg()].Garbage = true;
+               }
        }
        return true;
 }
@@ -298,12 +440,22 @@ bool EDSP::ApplyRequest(std::list<std::string> const &install,
                         pkgDepCache &Cache)
 {
        for (std::list<std::string>::const_iterator i = install.begin();
-            i != install.end(); ++i)
-               Cache.MarkInstall(Cache.FindPkg(*i), false);
+            i != install.end(); ++i) {
+               pkgCache::PkgIterator P = Cache.FindPkg(*i);
+               if (P.end() == true)
+                       _error->Warning("Package %s is not known, so can't be installed", i->c_str());
+               else
+                       Cache.MarkInstall(P, false);
+       }
 
        for (std::list<std::string>::const_iterator i = remove.begin();
-            i != remove.end(); ++i)
-               Cache.MarkDelete(Cache.FindPkg(*i));
+            i != remove.end(); ++i) {
+               pkgCache::PkgIterator P = Cache.FindPkg(*i);
+               if (P.end() == true)
+                       _error->Warning("Package %s is not known, so can't be installed", i->c_str());
+               else
+                       Cache.MarkDelete(P);
+       }
        return true;
 }
                                                                        /*}}}*/
@@ -314,17 +466,112 @@ bool EDSP::WriteSolution(pkgDepCache &Cache, FILE* output)
    for (pkgCache::PkgIterator Pkg = Cache.PkgBegin(); Pkg.end() == false; ++Pkg)
    {
       if (Cache[Pkg].Delete() == true)
-        fprintf(output, "Remove: %d\n", Cache.GetCandidateVer(Pkg)->ID);
+      {
+        fprintf(output, "Remove: %d\n", Pkg.CurrentVer()->ID);
+        if (Debug == true)
+           fprintf(output, "Package: %s\nVersion: %s\n", Pkg.FullName().c_str(), Pkg.CurrentVer().VerStr());
+      }
       else if (Cache[Pkg].NewInstall() == true || Cache[Pkg].Upgrade() == true)
+      {
         fprintf(output, "Install: %d\n", Cache.GetCandidateVer(Pkg)->ID);
+        if (Debug == true)
+           fprintf(output, "Package: %s\nVersion: %s\n", Pkg.FullName().c_str(), Cache.GetCandidateVer(Pkg).VerStr());
+      }
+      else if (Cache[Pkg].Garbage == true)
+      {
+        fprintf(output, "Autoremove: %d\n", Pkg.CurrentVer()->ID);
+        if (Debug == true)
+           fprintf(output, "Package: %s\nVersion: %s\n", Pkg.FullName().c_str(), Pkg.CurrentVer().VerStr());
+      }
       else
         continue;
-      if (Debug == true)
-        fprintf(output, "Package: %s\nVersion: %s\n", Pkg.FullName().c_str(), Cache.GetCandidateVer(Pkg).VerStr());
       fprintf(output, "\n");
    }
 
    return true;
 }
                                                                        /*}}}*/
-bool EDSP::WriteError(std::string const &message, FILE* output) { return false; }
+// EDSP::WriteProgess - pulse to the given file descriptor             /*{{{*/
+bool EDSP::WriteProgress(unsigned short const percent, const char* const message, FILE* output) {
+       fprintf(output, "Progress: %s\n", TimeRFC1123(time(NULL)).c_str());
+       fprintf(output, "Percentage: %d\n", percent);
+       fprintf(output, "Message: %s\n\n", message);
+       fflush(output);
+       return true;
+}
+                                                                       /*}}}*/
+// EDSP::WriteError - format an error message to be send to file descriptor /*{{{*/
+bool EDSP::WriteError(char const * const uuid, std::string const &message, FILE* output) {
+       fprintf(output, "Error: %s\n", uuid);
+       fprintf(output, "Message: %s\n\n", SubstVar(SubstVar(message, "\n\n", "\n.\n"), "\n", "\n ").c_str());
+       return true;
+}
+                                                                       /*}}}*/
+// EDSP::ExecuteSolver - fork requested solver and setup ipc pipes     {{{*/
+bool EDSP::ExecuteSolver(const char* const solver, int *solver_in, int *solver_out) {
+       std::vector<std::string> const solverDirs = _config->FindVector("Dir::Bin::Solvers");
+       std::string file;
+       for (std::vector<std::string>::const_iterator dir = solverDirs.begin();
+            dir != solverDirs.end(); ++dir) {
+               file = flCombine(*dir, solver);
+               if (RealFileExists(file.c_str()) == true)
+                       break;
+               file.clear();
+       }
+
+       if (file.empty() == true)
+               return _error->Error("Can't call external solver '%s' as it is not in a configured directory!", solver);
+       int external[4] = {-1, -1, -1, -1};
+       if (pipe(external) != 0 || pipe(external + 2) != 0)
+               return _error->Errno("Resolve", "Can't create needed IPC pipes for EDSP");
+       for (int i = 0; i < 4; ++i)
+               SetCloseExec(external[i], true);
+
+       pid_t Solver = ExecFork();
+       if (Solver == 0) {
+               dup2(external[0], STDIN_FILENO);
+               dup2(external[3], STDOUT_FILENO);
+               const char* calling[2] = { file.c_str(), 0 };
+               execv(calling[0], (char**) calling);
+               std::cerr << "Failed to execute solver '" << solver << "'!" << std::endl;
+               _exit(100);
+       }
+       close(external[0]);
+       close(external[3]);
+
+       if (WaitFd(external[1], true, 5) == false)
+               return _error->Errno("Resolve", "Timed out while Waiting on availability of solver stdin");
+
+       *solver_in = external[1];
+       *solver_out = external[2];
+       return true;
+}
+                                                                       /*}}}*/
+// EDSP::ResolveExternal - resolve problems by asking external for help        {{{*/
+bool EDSP::ResolveExternal(const char* const solver, pkgDepCache &Cache,
+                        bool const upgrade, bool const distUpgrade,
+                        bool const autoRemove, OpProgress *Progress) {
+       int solver_in, solver_out;
+       if (EDSP::ExecuteSolver(solver, &solver_in, &solver_out) == false)
+               return false;
+
+       FILE* output = fdopen(solver_in, "w");
+       if (output == NULL)
+               return _error->Errno("Resolve", "fdopen on solver stdin failed");
+
+       if (Progress != NULL)
+               Progress->OverallProgress(0, 100, 5, _("Execute external solver"));
+       EDSP::WriteRequest(Cache, output, upgrade, distUpgrade, autoRemove, Progress);
+       if (Progress != NULL)
+               Progress->OverallProgress(5, 100, 20, _("Execute external solver"));
+       EDSP::WriteScenario(Cache, output, Progress);
+       fclose(output);
+
+       if (Progress != NULL)
+               Progress->OverallProgress(25, 100, 75, _("Execute external solver"));
+       if (EDSP::ReadResponse(solver_out, Cache, Progress) == false)
+               return false;
+
+       return true;
+}
+                                                                       /*}}}*/