6 files changed, 114 insertions, 2 deletions
diff --git a/apt-pkg/cachefile.cc b/apt-pkg/cachefile.cc
index 92a3b201b..3e3540bbd 100644
--- a/apt-pkg/cachefile.cc
+++ b/apt-pkg/cachefile.cc
@@ -26,6 +26,7 @@
 #include <apt-pkg/depcache.h>
 #include <apt-pkg/mmap.h>
 #include <apt-pkg/pkgcache.h>
+#include <apt-pkg/indexfile.h>
 
 #include <string.h>
 #include <unistd.h>
@@ -186,6 +187,60 @@ bool pkgCacheFile::Open(OpProgress *Progress, bool WithLock)
    return true;
 }
 									/*}}}*/
+bool pkgCacheFile::AddIndexFile(pkgIndexFile * const File)		/*{{{*/
+{
+   if (SrcList == NULL)
+      if (BuildSourceList() == false)
+	 return false;
+   SrcList->AddVolatileFile(File);
+
+   if (Cache == nullptr || File->HasPackages() == false || File->Exists() == false)
+      return true;
+
+   if (File->FindInCache(*Cache).end() == false)
+      return _error->Warning("Duplicate sources.list entry %s",
+	    File->Describe().c_str());
+
+   if (ExternOwner == false)
+   {
+      delete DCache;
+      delete Cache;
+   }
+   delete Policy;
+   DCache = NULL;
+   Policy = NULL;
+   Cache = NULL;
+
+   if (ExternOwner == false)
+   {
+      // a dynamic mmap means that we have build at least parts of the cache
+      // in memory – which we might or might not have written to disk.
+      // Throwing away would therefore be a very costly operation we want to avoid
+      DynamicMMap * dynmmap = dynamic_cast<DynamicMMap*>(Map);
+      if (dynmmap != nullptr)
+      {
+	 {
+	    pkgCacheGenerator Gen(dynmmap, nullptr);
+	    if (File->Merge(Gen, nullptr) == false)
+	       return false;
+	 }
+	 Cache = new pkgCache(Map);
+	 return _error->PendingError() == false;
+      }
+      else
+      {
+	 delete Map;
+	 Map = NULL;
+      }
+   }
+   else
+   {
+      ExternOwner = false;
+      Map = NULL;
+   }
+   return true;
+}
+									/*}}}*/
 // CacheFile::RemoveCaches - remove all cache files from disk		/*{{{*/
 // ---------------------------------------------------------------------
 /* */
diff --git a/apt-pkg/cachefile.h b/apt-pkg/cachefile.h
index df724ff45..e23f37675 100644
--- a/apt-pkg/cachefile.h
+++ b/apt-pkg/cachefile.h
@@ -32,6 +32,7 @@
 class MMap;
 class pkgPolicy;
 class pkgSourceList;
+class pkgIndexFile;
 class OpProgress;
 
 class pkgCacheFile
@@ -74,6 +75,8 @@ class pkgCacheFile
    static void RemoveCaches();
    void Close();
 
+   bool AddIndexFile(pkgIndexFile * const File);
+
    inline pkgCache* GetPkgCache() { BuildCaches(NULL, false); return Cache; };
    inline pkgDepCache* GetDepCache() { BuildDepCache(); return DCache; };
    inline pkgPolicy* GetPolicy() { BuildPolicy(); return Policy; };
diff --git a/apt-pkg/deb/debindexfile.cc b/apt-pkg/deb/debindexfile.cc
index c11efd0ae..84dabc06b 100644
--- a/apt-pkg/deb/debindexfile.cc
+++ b/apt-pkg/deb/debindexfile.cc
@@ -297,6 +297,39 @@ std::string debDebianSourceDirIndex::GetComponent() const
    return "local-control";
 }
 									/*}}}*/
+// String Package Index - a string of Packages file content		/*{{{*/
+std::string debStringPackageIndex::GetArchitecture() const
+{
+   return std::string();
+}
+std::string debStringPackageIndex::GetComponent() const
+{
+   return "apt-tmp-index";
+}
+uint8_t debStringPackageIndex::GetIndexFlags() const
+{
+   return pkgCache::Flag::NotSource;
+}
+const pkgIndexFile::Type *debStringPackageIndex::GetType() const
+{
+   return pkgIndexFile::Type::GetType("Debian Package Index");
+}
+debStringPackageIndex::debStringPackageIndex(std::string const &content) :
+   pkgDebianIndexRealFile("", false), d(NULL)
+{
+   char fn[1024];
+   std::string const tempdir = GetTempDir();
+   snprintf(fn, sizeof(fn), "%s/%s.XXXXXX", tempdir.c_str(), "apt-tmp-index");
+   int const fd = mkstemp(fn);
+   File = fn;
+   FileFd::Write(fd, content.data(), content.length());
+   close(fd);
+}
+debStringPackageIndex::~debStringPackageIndex()
+{
+   RemoveFile("~debStringPackageIndex", File);
+}
+									/*}}}*/
 
 // Index File types for Debian						/*{{{*/
 class APT_HIDDEN debIFTypeSrc : public pkgIndexFile::Type
diff --git a/apt-pkg/deb/debindexfile.h b/apt-pkg/deb/debindexfile.h
index 890141dff..3652f631c 100644
--- a/apt-pkg/deb/debindexfile.h
+++ b/apt-pkg/deb/debindexfile.h
@@ -176,4 +176,23 @@ public:
    virtual const Type *GetType() const APT_OVERRIDE APT_CONST;
 };
 
+class debStringPackageIndex : public pkgDebianIndexRealFile
+{
+   void * const d;
+protected:
+   virtual std::string GetArchitecture() const APT_OVERRIDE;
+   virtual std::string GetComponent() const APT_OVERRIDE;
+   virtual uint8_t GetIndexFlags() const APT_OVERRIDE;
+
+public:
+   virtual const Type *GetType() const APT_OVERRIDE APT_CONST;
+
+   // Interface for the Cache Generator
+   virtual bool HasPackages() const APT_OVERRIDE {return true;};
+   // Abort if the file does not exist.
+   virtual bool Exists() const APT_OVERRIDE {return true;};
+
+   debStringPackageIndex(std::string const &content);
+   virtual ~debStringPackageIndex();
+};
 #endif
diff --git a/apt-pkg/indexfile.cc b/apt-pkg/indexfile.cc
index dfd482c04..657cdfb36 100644
--- a/apt-pkg/indexfile.cc
+++ b/apt-pkg/indexfile.cc
@@ -267,7 +267,9 @@ std::string pkgDebianIndexTargetFile::GetProgressDescription() const
 pkgDebianIndexRealFile::pkgDebianIndexRealFile(std::string const &pFile, bool const Trusted) :/*{{{*/
    pkgDebianIndexFile(Trusted), d(NULL)
 {
-   if (pFile == "/nonexistent/stdin")
+   if (pFile.empty())
+      ;
+   else if (pFile == "/nonexistent/stdin")
       File = pFile;
    else
       File = flAbsPath(pFile);
diff --git a/apt-pkg/pkgcachegen.cc b/apt-pkg/pkgcachegen.cc
index 0dbac3df8..120b0c414 100644
--- a/apt-pkg/pkgcachegen.cc
+++ b/apt-pkg/pkgcachegen.cc
@@ -1735,7 +1735,7 @@ bool pkgCacheGenerator::MakeStatusCache(pkgSourceList &List,OpProgress *Progress
    }
 
    if (Debug == true)
-      std::clog << "Caches done. Now bring in the volatile files (if any)" << std::endl;
+      std::clog << "Caches done. " << (volatile_fine ? "No volatile files, so we are done here." : "Now bring in the volatile files") << std::endl;
 
    if (volatile_fine == false)
    {