Adding upstream version 1.8.2.3.upstream/1.8.2.3upstream

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

14 files changed, 2667 insertions, 0 deletions

diff --git a/apt-inst/CMakeLists.txt b/apt-inst/CMakeLists.txt
new file mode 100644
index 0000000..31da115
--- /dev/null
+++ b/apt-inst/CMakeLists.txt
@@ -0,0 +1,28 @@
+# Include apt-pkg directly, as some files have #include <system.h>
+include_directories(${PROJECT_BINARY_DIR}/include/apt-pkg)
+
+# Set the version of the library
+set(MAJOR 2.0)
+set(MINOR 0)
+set(APT_INST_MAJOR ${MAJOR} PARENT_SCOPE)
+
+# Definition of the C++ files used to build the library - note that this
+# is expanded at CMake time, so you have to rerun cmake if you add or remove
+# a file (you can just run cmake . in the build directory)
+file(GLOB_RECURSE library "*.cc")
+file(GLOB_RECURSE headers "*.h")
+
+# Create a library using the C++ files
+add_library(apt-inst SHARED ${library})
+
+# Link the library and set the SONAME
+target_link_libraries(apt-inst PUBLIC apt-pkg ${CMAKE_THREAD_LIBS_INIT})
+target_link_libraries(apt-inst PRIVATE ${CMAKE_THREAD_LIBS_INIT})
+set_target_properties(apt-inst PROPERTIES VERSION ${MAJOR}.${MINOR})
+set_target_properties(apt-inst PROPERTIES SOVERSION ${MAJOR})
+add_version_script(apt-inst)
+
+# Install the library and the headers
+install(TARGETS apt-inst LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
+install(FILES ${headers} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/apt-pkg)
+flatify(${PROJECT_BINARY_DIR}/include/apt-pkg/ "${headers}")
diff --git a/apt-inst/contrib/arfile.cc b/apt-inst/contrib/arfile.cc
new file mode 100644
index 0000000..6d4a1f1
--- /dev/null
+++ b/apt-inst/contrib/arfile.cc
@@ -0,0 +1,179 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   AR File - Handle an 'AR' archive
+   
+   AR Archives have plain text headers at the start of each file
+   section. The headers are aligned on a 2 byte boundary.
+   
+   Information about the structure of AR files can be found in ar(5)
+   on a BSD system, or in the binutils source.
+
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/arfile.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/strutl.h>
+
+#include <string>
+#include <string.h>
+#include <sys/types.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+struct ARArchive::MemberHeader
+{
+   char Name[16];
+   char MTime[12];
+   char UID[6];
+   char GID[6];
+   char Mode[8];
+   char Size[10];
+   char Magic[2];
+};
+
+// ARArchive::ARArchive - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+ARArchive::ARArchive(FileFd &File) : List(0), File(File)
+{
+   LoadHeaders();
+}
+									/*}}}*/
+// ARArchive::~ARArchive - Destructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+ARArchive::~ARArchive()
+{
+   while (List != 0)
+   {
+      Member *Tmp = List;
+      List = List->Next;
+      delete Tmp;
+   }   
+}
+									/*}}}*/
+// ARArchive::LoadHeaders - Load the headers from each file		/*{{{*/
+// ---------------------------------------------------------------------
+/* AR files are structured with a 8 byte magic string followed by a 60
+   byte plain text header then the file data, another header, data, etc */
+bool ARArchive::LoadHeaders()
+{
+   off_t Left = File.Size();
+   
+   // Check the magic byte
+   char Magic[8];
+   if (File.Read(Magic,sizeof(Magic)) == false)
+      return false;
+   if (memcmp(Magic,"!<arch>\012",sizeof(Magic)) != 0)
+      return _error->Error(_("Invalid archive signature"));
+   Left -= sizeof(Magic);
+   
+   // Read the member list
+   while (Left > 0)
+   {
+      MemberHeader Head;
+      if (File.Read(&Head,sizeof(Head)) == false)
+	 return _error->Error(_("Error reading archive member header"));
+      Left -= sizeof(Head);
+
+      // Convert all of the integer members
+      Member *Memb = new Member();
+      if (StrToNum(Head.MTime,Memb->MTime,sizeof(Head.MTime)) == false ||
+	  StrToNum(Head.UID,Memb->UID,sizeof(Head.UID)) == false ||
+	  StrToNum(Head.GID,Memb->GID,sizeof(Head.GID)) == false ||
+	  StrToNum(Head.Mode,Memb->Mode,sizeof(Head.Mode),8) == false ||
+	  StrToNum(Head.Size,Memb->Size,sizeof(Head.Size)) == false)
+      {
+	 delete Memb;
+	 return _error->Error(_("Invalid archive member header"));
+      }
+
+      if (Left < 0 || Memb->Size > static_cast<unsigned long long>(Left))
+      {
+	 delete Memb;
+	 return _error->Error(_("Invalid archive member header"));
+      }
+      // Check for an extra long name string
+      if (memcmp(Head.Name,"#1/",3) == 0)
+      {
+	 char S[300];
+	 unsigned long Len;
+	 if (StrToNum(Head.Name+3,Len,sizeof(Head.Size)-3) == false ||
+	     Len >= sizeof(S))
+	 {
+	    delete Memb;
+	    return _error->Error(_("Invalid archive member header"));
+	 }
+
+	 if (Len > Memb->Size)
+	 {
+	    delete Memb;
+	    return _error->Error(_("Invalid archive member header"));
+	 }
+
+	 if (File.Read(S,Len) == false)
+	 {
+	    delete Memb;
+	    return false;
+	 }
+	 S[Len] = 0;
+	 Memb->Name = S;
+	 Memb->Size -= Len;
+	 Left -= Len;
+      }
+      else
+      {
+	 unsigned int I = sizeof(Head.Name) - 1;
+	 for (; Head.Name[I] == ' ' || Head.Name[I] == '/'; I--)
+	 {
+	    if (I == 0)
+	    {
+	       delete Memb;
+	       return _error->Error(_("Invalid archive member header"));
+	    }
+	 }
+	 Memb->Name = std::string(Head.Name,I+1);
+      }
+
+      // Account for the AR header alignment 
+      off_t Skip = Memb->Size % 2;
+      
+      // Add it to the list
+      Memb->Next = List;
+      List = Memb;
+      Memb->Start = File.Tell();
+      if (File.Skip(Memb->Size + Skip) == false)
+	 return false;
+      if (Left < (off_t)(Memb->Size + Skip))
+	 return _error->Error(_("Archive is too short"));
+      Left -= Memb->Size + Skip;
+   }   
+   if (Left != 0)
+      return _error->Error(_("Failed to read the archive headers"));
+   
+   return true;
+}
+									/*}}}*/
+// ARArchive::FindMember - Find a name in the member list		/*{{{*/
+// ---------------------------------------------------------------------
+/* Find a member with the given name */
+const ARArchive::Member *ARArchive::FindMember(const char *Name) const
+{
+   const Member *Res = List;
+   while (Res != 0)
+   {
+      if (Res->Name == Name)
+	 return Res;
+      Res = Res->Next;
+   }
+   
+   return 0;
+}
+									/*}}}*/
diff --git a/apt-inst/contrib/arfile.h b/apt-inst/contrib/arfile.h
new file mode 100644
index 0000000..8124208
--- /dev/null
+++ b/apt-inst/contrib/arfile.h
@@ -0,0 +1,69 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   AR File - Handle an 'AR' archive
+   
+   This is a reader for the usual 4.4 BSD AR format. It allows raw
+   stream access to a single member at a time. Basically all this class
+   provides is header parsing and verification. It is up to the client
+   to correctly make use of the stream start/stop points.
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_ARFILE_H
+#define PKGLIB_ARFILE_H
+
+#include <apt-pkg/macros.h>
+#include <string>
+#ifndef APT_8_CLEANER_HEADERS
+#include <apt-pkg/fileutl.h>
+#endif
+
+class FileFd;
+
+class ARArchive
+{
+   struct MemberHeader;
+   public:
+   struct Member;
+   
+   protected:
+
+   // Linked list of members
+   Member *List;
+   
+   bool LoadHeaders();
+
+   public:
+   
+   // The stream file
+   FileFd &File;
+
+   // Locate a member by name
+   const Member *FindMember(const char *Name) const;
+   inline Member *Members() { return List; }
+   
+   ARArchive(FileFd &File);
+   ~ARArchive();
+};
+
+// A member of the archive
+struct ARArchive::Member
+{
+   // Fields from the header
+   std::string Name;
+   unsigned long MTime;
+   unsigned long UID;
+   unsigned long GID;
+   unsigned long Mode;
+   unsigned long long Size;
+   
+   // Location of the data.
+   unsigned long long Start;
+   Member *Next;
+   
+   Member() : Start(0), Next(0) {};
+};
+
+#endif
diff --git a/apt-inst/contrib/extracttar.cc b/apt-inst/contrib/extracttar.cc
new file mode 100644
index 0000000..cbee4d1
--- /dev/null
+++ b/apt-inst/contrib/extracttar.cc
@@ -0,0 +1,329 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Extract a Tar - Tar Extractor
+
+   Some performance measurements showed that zlib performed quite poorly
+   in comparison to a forked gzip process. This tar extractor makes use
+   of the fact that dup'd file descriptors have the same seek pointer
+   and that gzip will not read past the end of a compressed stream, 
+   even if there is more data. We use the dup property to track extraction
+   progress and the gzip feature to just feed gzip a fd in the middle
+   of an AR file. 
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/extracttar.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/strutl.h>
+
+#include <algorithm>
+#include <iostream>
+#include <string>
+#include <fcntl.h>
+#include <signal.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+using namespace std;
+    
+// The on disk header for a tar file.
+struct ExtractTar::TarHeader
+{
+   char Name[100];
+   char Mode[8];
+   char UserID[8];
+   char GroupID[8];
+   char Size[12];
+   char MTime[12];
+   char Checksum[8];
+   char LinkFlag;
+   char LinkName[100];
+   char MagicNumber[8];
+   char UserName[32];
+   char GroupName[32];
+   char Major[8];
+   char Minor[8];      
+};
+
+// We need to read long names (names and link targets) into memory, so let's
+// have a limit (shamelessly stolen from libarchive) to avoid people OOMing
+// us with large streams.
+static const unsigned long long APT_LONGNAME_LIMIT = 1048576llu;
+
+// A file size limit that we allow extracting. Currently, that's 128 GB.
+// We also should leave some wiggle room for code adding files to it, and
+// possibly conversion for signed, so this should not be larger than like 2**62.
+static const unsigned long long APT_FILESIZE_LIMIT = 1llu << 37;
+
+// ExtractTar::ExtractTar - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+ExtractTar::ExtractTar(FileFd &Fd,unsigned long long Max,string DecompressionProgram)
+	: File(Fd), MaxInSize(Max), DecompressProg(DecompressionProgram)
+{
+   GZPid = -1;
+   Eof = false;
+}
+									/*}}}*/
+// ExtractTar::ExtractTar - Destructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+ExtractTar::~ExtractTar()
+{
+   // Error close
+   Done();
+}
+									/*}}}*/
+// ExtractTar::Done - Reap the gzip sub process				/*{{{*/
+bool ExtractTar::Done(bool)
+{
+   return Done();
+}
+bool ExtractTar::Done()
+{
+   return InFd.Close();
+}
+									/*}}}*/
+// ExtractTar::StartGzip - Startup gzip					/*{{{*/
+// ---------------------------------------------------------------------
+/* This creates a gzip sub process that has its input as the file itself.
+   If this tar file is embedded into something like an ar file then 
+   gzip will efficiently ignore the extra bits. */
+bool ExtractTar::StartGzip()
+{
+   if (DecompressProg.empty())
+   {
+      InFd.OpenDescriptor(File.Fd(), FileFd::ReadOnly, FileFd::None, false);
+      return true;
+   }
+
+   std::vector<APT::Configuration::Compressor> const compressors = APT::Configuration::getCompressors();
+   std::vector<APT::Configuration::Compressor>::const_iterator compressor = compressors.begin();
+   for (; compressor != compressors.end(); ++compressor) {
+      if (compressor->Name == DecompressProg) {
+	 return InFd.OpenDescriptor(File.Fd(), FileFd::ReadOnly, *compressor, false);
+      }
+   }
+
+   return _error->Error(_("Cannot find a configured compressor for '%s'"),
+			DecompressProg.c_str());
+
+}
+									/*}}}*/
+// ExtractTar::Go - Perform extraction					/*{{{*/
+// ---------------------------------------------------------------------
+/* This reads each 512 byte block from the archive and extracts the header
+   information into the Item structure. Then it resolves the UID/GID and
+   invokes the correct processing function. */
+bool ExtractTar::Go(pkgDirStream &Stream)
+{   
+   if (StartGzip() == false)
+      return false;
+   
+   // Loop over all blocks
+   string LastLongLink, ItemLink;
+   string LastLongName, ItemName;
+   while (1)
+   {
+      bool BadRecord = false;      
+      unsigned char Block[512];      
+      if (InFd.Read(Block,sizeof(Block),true) == false)
+	 return false;
+      
+      if (InFd.Eof() == true)
+	 break;
+
+      // Get the checksum
+      TarHeader *Tar = (TarHeader *)Block;
+      unsigned long CheckSum;
+      if (StrToNum(Tar->Checksum,CheckSum,sizeof(Tar->Checksum),8) == false)
+	 return _error->Error(_("Corrupted archive"));
+      
+      /* Compute the checksum field. The actual checksum is blanked out
+         with spaces so it is not included in the computation */
+      unsigned long NewSum = 0;
+      memset(Tar->Checksum,' ',sizeof(Tar->Checksum));
+      for (int I = 0; I != sizeof(Block); I++)
+	 NewSum += Block[I];
+      
+      /* Check for a block of nulls - in this case we kill gzip, GNU tar
+       	 does this.. */
+      if (NewSum == ' '*sizeof(Tar->Checksum))
+	 return Done();
+      
+      if (NewSum != CheckSum)
+	 return _error->Error(_("Tar checksum failed, archive corrupted"));
+   
+      // Decode all of the fields
+      pkgDirStream::Item Itm;
+      if (StrToNum(Tar->Mode,Itm.Mode,sizeof(Tar->Mode),8) == false ||
+          (Base256ToNum(Tar->UserID,Itm.UID,8) == false &&
+	     StrToNum(Tar->UserID,Itm.UID,sizeof(Tar->UserID),8) == false) ||
+          (Base256ToNum(Tar->GroupID,Itm.GID,8) == false &&
+	     StrToNum(Tar->GroupID,Itm.GID,sizeof(Tar->GroupID),8) == false) ||
+          (Base256ToNum(Tar->Size,Itm.Size,12) == false &&
+	     StrToNum(Tar->Size,Itm.Size,sizeof(Tar->Size),8) == false) ||
+          (Base256ToNum(Tar->MTime,Itm.MTime,12) == false &&
+	     StrToNum(Tar->MTime,Itm.MTime,sizeof(Tar->MTime),8) == false) ||
+	  StrToNum(Tar->Major,Itm.Major,sizeof(Tar->Major),8) == false ||
+	  StrToNum(Tar->Minor,Itm.Minor,sizeof(Tar->Minor),8) == false)
+	 return _error->Error(_("Corrupted archive"));
+
+      // Security check. Prevents overflows below the code when rounding up in skip/copy code,
+      // and provides modest protection against decompression bombs.
+      if (Itm.Size > APT_FILESIZE_LIMIT)
+	 return _error->Error("Tar member too large: %llu > %llu bytes", Itm.Size, APT_FILESIZE_LIMIT);
+
+      // Grab the filename and link target: use last long name if one was
+      // set, otherwise use the header value as-is, but remember that it may
+      // fill the entire 100-byte block and needs to be zero-terminated.
+      // See Debian Bug #689582.
+      if (LastLongName.empty() == false)
+	 Itm.Name = (char *)LastLongName.c_str();
+      else
+	 Itm.Name = (char *)ItemName.assign(Tar->Name, sizeof(Tar->Name)).c_str();
+      if (Itm.Name[0] == '.' && Itm.Name[1] == '/' && Itm.Name[2] != 0)
+	 Itm.Name += 2;
+
+      if (LastLongLink.empty() == false)
+	 Itm.LinkTarget = (char *)LastLongLink.c_str();
+      else
+	 Itm.LinkTarget = (char *)ItemLink.assign(Tar->LinkName, sizeof(Tar->LinkName)).c_str();
+
+      // Convert the type over
+      switch (Tar->LinkFlag)
+      {
+	 case NormalFile0:
+	 case NormalFile:
+	 Itm.Type = pkgDirStream::Item::File;
+	 break;
+	 
+	 case HardLink:
+	 Itm.Type = pkgDirStream::Item::HardLink;
+	 break;
+	 
+	 case SymbolicLink:
+	 Itm.Type = pkgDirStream::Item::SymbolicLink;
+	 break;
+	 
+	 case CharacterDevice:
+	 Itm.Type = pkgDirStream::Item::CharDevice;
+	 break;
+	    
+	 case BlockDevice:
+	 Itm.Type = pkgDirStream::Item::BlockDevice;
+	 break;
+	 
+	 case Directory:
+	 Itm.Type = pkgDirStream::Item::Directory;
+	 break;
+	 
+	 case FIFO:
+	 Itm.Type = pkgDirStream::Item::FIFO;
+	 break;
+
+	 case GNU_LongLink:
+	 {
+	    unsigned long long Length = Itm.Size;
+	    unsigned char Block[512];
+	    if (Length > APT_LONGNAME_LIMIT)
+	       return _error->Error("Long name to large: %llu bytes > %llu bytes", Length, APT_LONGNAME_LIMIT);
+	    while (Length > 0)
+	    {
+	       if (InFd.Read(Block,sizeof(Block),true) == false)
+		  return false;
+	       if (Length <= sizeof(Block))
+	       {
+		  LastLongLink.append(Block,Block+sizeof(Block));
+		  break;
+	       }	       
+	       LastLongLink.append(Block,Block+sizeof(Block));
+	       Length -= sizeof(Block);
+	    }
+	    continue;
+	 }
+	 
+	 case GNU_LongName:
+	 {
+	    unsigned long long Length = Itm.Size;
+	    unsigned char Block[512];
+	    if (Length > APT_LONGNAME_LIMIT)
+	       return _error->Error("Long name to large: %llu bytes > %llu bytes", Length, APT_LONGNAME_LIMIT);
+	    while (Length > 0)
+	    {
+	       if (InFd.Read(Block,sizeof(Block),true) == false)
+		  return false;
+	       if (Length < sizeof(Block))
+	       {
+		  LastLongName.append(Block,Block+sizeof(Block));
+		  break;
+	       }	       
+	       LastLongName.append(Block,Block+sizeof(Block));
+	       Length -= sizeof(Block);
+	    }
+	    continue;
+	 }
+	 
+	 default:
+	 BadRecord = true;
+	 _error->Warning(_("Unknown TAR header type %u"), (unsigned)Tar->LinkFlag);
+	 break;
+      }
+      
+      int Fd = -1;
+      if (BadRecord == false)
+	 if (Stream.DoItem(Itm,Fd) == false)
+	    return false;
+      
+      // Copy the file over the FD
+      unsigned long long Size = Itm.Size;
+      while (Size != 0)
+      {
+	 unsigned char Junk[32*1024];
+	 unsigned long Read = min(Size, (unsigned long long)sizeof(Junk));
+	 if (InFd.Read(Junk,((Read+511)/512)*512) == false)
+	    return false;
+	 
+	 if (BadRecord == false)
+	 {
+	    if (Fd > 0)
+	    {
+	       if (write(Fd,Junk,Read) != (signed)Read)
+		  return Stream.Fail(Itm,Fd);
+	    }
+	    else
+	    {
+	       /* An Fd of -2 means to send to a special processing
+		  function */
+	       if (Fd == -2)
+		  if (Stream.Process(Itm,Junk,Read,Itm.Size - Size) == false)
+		     return Stream.Fail(Itm,Fd);
+	    }
+	 }
+	 
+	 Size -= Read;
+      }
+      
+      // And finish up
+      if (BadRecord == false)
+	 if (Stream.FinishedFile(Itm,Fd) == false)
+	    return false;
+      
+      LastLongName.erase();
+      LastLongLink.erase();
+   }
+   
+   return Done();
+}
+									/*}}}*/
diff --git a/apt-inst/contrib/extracttar.h b/apt-inst/contrib/extracttar.h
new file mode 100644
index 0000000..c0b340e
--- /dev/null
+++ b/apt-inst/contrib/extracttar.h
@@ -0,0 +1,61 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Extract a Tar - Tar Extractor
+   
+   The tar extractor takes an ordinary gzip compressed tar stream from 
+   the given file and explodes it, passing the individual items to the
+   given Directory Stream for processing.
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_EXTRACTTAR_H
+#define PKGLIB_EXTRACTTAR_H
+
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/macros.h>
+
+#include <string>
+
+#ifndef APT_8_CLEANER_HEADERS
+#include <apt-pkg/dirstream.h>
+#include <algorithm>
+using std::min;
+#endif
+
+class pkgDirStream;
+
+class ExtractTar
+{
+   protected:
+   
+   struct TarHeader;
+   
+   // The varios types items can be
+   enum ItemType {NormalFile0 = '\0',NormalFile = '0',HardLink = '1',
+                  SymbolicLink = '2',CharacterDevice = '3',
+                  BlockDevice = '4',Directory = '5',FIFO = '6',
+                  GNU_LongLink = 'K',GNU_LongName = 'L'};
+
+   FileFd &File;
+   unsigned long long MaxInSize;
+   int GZPid;
+   FileFd InFd;
+   bool Eof;
+   std::string DecompressProg;
+   
+   // Fork and reap gzip
+   bool StartGzip();
+   bool Done();
+   APT_DEPRECATED_MSG("Parameter Force is ignored, use Done() instead.") bool Done(bool Force);
+
+   public:
+
+   bool Go(pkgDirStream &Stream);
+
+   ExtractTar(FileFd &Fd,unsigned long long Max,std::string DecompressionProgram);
+   virtual ~ExtractTar();
+};
+
+#endif
diff --git a/apt-inst/deb/debfile.cc b/apt-inst/deb/debfile.cc
new file mode 100644
index 0000000..bef0cd0
--- /dev/null
+++ b/apt-inst/deb/debfile.cc
@@ -0,0 +1,265 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Debian Archive File (.deb)
+   
+   .DEB archives are AR files containing two tars and an empty marker
+   member called 'debian-binary'. The two tars contain the meta data and
+   the actual archive contents. Thus this class is a very simple wrapper
+   around ar/tar to simply extract the right tar files.
+   
+   It also uses the deb package list parser to parse the control file 
+   into the cache.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/arfile.h>
+#include <apt-pkg/debfile.h>
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/extracttar.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/tagfile.h>
+
+#include <string>
+#include <vector>
+#include <string.h>
+#include <sys/stat.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+// DebFile::debDebFile - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* Open the AR file and check for consistency */
+debDebFile::debDebFile(FileFd &File) : File(File), AR(File)
+{
+   if (_error->PendingError() == true)
+      return;
+
+   if (!CheckMember("debian-binary")) {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "debian-binary");
+      return;
+   }
+
+   if (!CheckMember("control.tar") &&
+       !CheckMember("control.tar.gz") &&
+       !CheckMember("control.tar.xz") &&
+       !CheckMember("control.tar.zst"))
+   {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "control.tar");
+      return;
+   }
+
+   if (!CheckMember("data.tar") &&
+       !CheckMember("data.tar.gz") &&
+       !CheckMember("data.tar.bz2") &&
+       !CheckMember("data.tar.lzma") &&
+       !CheckMember("data.tar.xz") &&
+       !CheckMember("data.tar.zst"))
+   {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "data.tar");
+      return;
+   }
+}
+									/*}}}*/
+// DebFile::CheckMember - Check if a named member is in the archive	/*{{{*/
+// ---------------------------------------------------------------------
+/* This is used to check for a correct deb and to give nicer error messages
+   for people playing around. */
+bool debDebFile::CheckMember(const char *Name)
+{
+   if (AR.FindMember(Name) == 0)
+      return false;
+   return true;
+}
+									/*}}}*/
+// DebFile::GotoMember - Jump to a Member				/*{{{*/
+// ---------------------------------------------------------------------
+/* Jump in the file to the start of a named member and return the information
+   about that member. The caller can then read from the file up to the 
+   returned size. Note, since this relies on the file position this is
+   a destructive operation, it also changes the last returned Member
+   structure - so don't nest them! */
+const ARArchive::Member *debDebFile::GotoMember(const char *Name)
+{
+   // Get the archive member and positition the file
+   const ARArchive::Member *Member = AR.FindMember(Name);
+   if (Member == 0)
+   {
+      return 0;
+   }
+   if (File.Seek(Member->Start) == false)
+      return 0;
+      
+   return Member;
+}
+									/*}}}*/
+// DebFile::ExtractTarMember - Extract the contents of a tar member	/*{{{*/
+// ---------------------------------------------------------------------
+/* Simple wrapper around tar.. */
+bool debDebFile::ExtractTarMember(pkgDirStream &Stream,const char *Name)
+{
+   // Get the archive member
+   const ARArchive::Member *Member = NULL;
+   std::string Compressor;
+
+   std::vector<APT::Configuration::Compressor> compressor = APT::Configuration::getCompressors();
+   for (std::vector<APT::Configuration::Compressor>::const_iterator c = compressor.begin();
+	c != compressor.end(); ++c)
+   {
+      Member = AR.FindMember(std::string(Name).append(c->Extension).c_str());
+      if (Member == NULL)
+	 continue;
+      Compressor = c->Name;
+      break;
+   }
+
+   if (Member == NULL)
+      Member = AR.FindMember(std::string(Name).c_str());
+
+   if (Member == NULL)
+   {
+      std::string ext = std::string(Name) + ".{";
+      for (std::vector<APT::Configuration::Compressor>::const_iterator c = compressor.begin();
+	   c != compressor.end(); ++c) {
+	 if (!c->Extension.empty())
+	    ext.append(c->Extension.substr(1));
+      }
+      ext.append("}");
+      return _error->Error(_("Internal error, could not locate member %s"), ext.c_str());
+   }
+
+   if (File.Seek(Member->Start) == false)
+      return false;
+
+   // Prepare Tar
+   ExtractTar Tar(File,Member->Size,Compressor);
+   if (_error->PendingError() == true)
+      return false;
+   return Tar.Go(Stream);
+}
+									/*}}}*/
+// DebFile::ExtractArchive - Extract the archive data itself		/*{{{*/
+// ---------------------------------------------------------------------
+/* Simple wrapper around DebFile::ExtractTarMember. */
+bool debDebFile::ExtractArchive(pkgDirStream &Stream)
+{
+   return ExtractTarMember(Stream, "data.tar");
+}
+									/*}}}*/
+
+// DebFile::ControlExtract::DoItem - Control Tar Extraction		/*{{{*/
+// ---------------------------------------------------------------------
+/* This directory stream handler for the control tar handles extracting
+   it into the temporary meta directory. It only extracts files, it does
+   not create directories, links or anything else. */
+bool debDebFile::ControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   if (Itm.Type != Item::File)
+      return true;
+   
+   /* Cleanse the file name, prevent people from trying to unpack into
+      absolute paths, .., etc */
+   for (char *I = Itm.Name; *I != 0; I++)
+      if (*I == '/')
+	 *I = '_';
+
+   /* Force the ownership to be root and ensure correct permissions, 
+      go-w, the rest are left untouched */
+   Itm.UID = 0;
+   Itm.GID = 0;
+   Itm.Mode &= ~(S_IWGRP | S_IWOTH);
+   
+   return pkgDirStream::DoItem(Itm,Fd);
+}
+									/*}}}*/
+
+// MemControlExtract::DoItem - Check if it is the control file		/*{{{*/
+// ---------------------------------------------------------------------
+/* This sets up to extract the control block member file into a memory 
+   block of just the right size. All other files go into the bit bucket. */
+
+// Upper size limit for control files. Two reasons for having a limit here:
+//
+// 1. We read those files into memory and want to avoid being killed by OOM
+//
+// 2. We allocate (Itm.Size+2)-large arrays, so this can overflow if Itm.Size
+// becomes 2**64-2 or larger. This is obviously
+//
+// 64 MiB seems like a terribly large size that everyone should be happy with.
+static const unsigned long long DEB_CONTROL_SIZE_LIMIT = 64 * 1024 * 1024;
+bool debDebFile::MemControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   // At the control file, allocate buffer memory.
+   if (Member == Itm.Name)
+   {
+      if (Itm.Size > DEB_CONTROL_SIZE_LIMIT)
+	 return _error->Error("Control file too large: %llu > %llu bytes", Itm.Size, DEB_CONTROL_SIZE_LIMIT);
+      delete [] Control;
+      Control = new char[Itm.Size+2];
+      IsControl = true;
+      Fd = -2; // Signal to pass to Process
+      Length = Itm.Size;
+   }   
+   else
+      IsControl = false;
+   
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Process - Process extracting the control file	/*{{{*/
+// ---------------------------------------------------------------------
+/* Just memcopy the block from the tar extractor and put it in the right
+   place in the pre-allocated memory block. */
+bool debDebFile::MemControlExtract::Process(Item &/*Itm*/,const unsigned char *Data,
+			     unsigned long long Size,unsigned long long Pos)
+{
+   memcpy(Control + Pos, Data,Size);
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Read - Read the control information from the deb	/*{{{*/
+// ---------------------------------------------------------------------
+/* This uses the internal tar extractor to fetch the control file, and then
+   it parses it into a tag section parser. */
+bool debDebFile::MemControlExtract::Read(debDebFile &Deb)
+{
+   if (Deb.ExtractTarMember(*this, "control.tar") == false)
+      return false;
+
+   if (Control == 0)
+      return true;
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   if (Section.Scan(Control,Length+2) == false)
+      return _error->Error(_("Unparsable control file"));
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::TakeControl - Parse a memory block		/*{{{*/
+// ---------------------------------------------------------------------
+/* The given memory block is loaded into the parser and parsed as a control
+   record. */
+bool debDebFile::MemControlExtract::TakeControl(const void *Data,unsigned long long Size)
+{
+   if (Size > DEB_CONTROL_SIZE_LIMIT)
+      return _error->Error("Control file too large: %llu > %llu bytes", Size, DEB_CONTROL_SIZE_LIMIT);
+
+   delete [] Control;
+   Control = new char[Size+2];
+   Length = Size;
+   memcpy(Control,Data,Size);
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   return Section.Scan(Control,Length+2);
+}
+									/*}}}*/
+
diff --git a/apt-inst/deb/debfile.h b/apt-inst/deb/debfile.h
new file mode 100644
index 0000000..23a76bf
--- /dev/null
+++ b/apt-inst/deb/debfile.h
@@ -0,0 +1,95 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Debian Archive File (.deb)
+
+   This Class handles all the operations performed directly on .deb 
+   files. It makes use of the AR and TAR classes to give the necessary
+   external interface.
+   
+   There are only two things that can be done with a raw package, 
+   extract it's control information and extract the contents itself. 
+
+   This should probably subclass an as-yet unwritten super class to
+   produce a generic archive mechanism.
+  
+   The memory control file extractor is useful to extract a single file
+   into memory from the control.tar.gz
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_DEBFILE_H
+#define PKGLIB_DEBFILE_H
+
+#include <apt-pkg/arfile.h>
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/macros.h>
+#include <apt-pkg/tagfile.h>
+
+#include <string>
+
+#ifndef APT_8_CLEANER_HEADERS
+#include <apt-pkg/md5.h>
+#endif
+#ifndef APT_10_CLEANER_HEADERS
+#include <apt-pkg/pkgcache.h>
+#endif
+
+class FileFd;
+
+class debDebFile
+{
+   protected:
+   
+   FileFd &File;
+   ARArchive AR;
+   
+   bool CheckMember(const char *Name);
+   
+   public:
+   class ControlExtract;
+   class MemControlExtract;
+
+   bool ExtractTarMember(pkgDirStream &Stream, const char *Name);
+   bool ExtractArchive(pkgDirStream &Stream);
+   const ARArchive::Member *GotoMember(const char *Name);
+   inline FileFd &GetFile() {return File;};
+   
+   debDebFile(FileFd &File);
+};
+
+class debDebFile::ControlExtract : public pkgDirStream
+{
+   public:
+   
+   virtual bool DoItem(Item &Itm,int &Fd) APT_OVERRIDE;
+};
+
+class debDebFile::MemControlExtract : public pkgDirStream
+{
+   bool IsControl;
+   
+   public:
+   
+   char *Control;
+   pkgTagSection Section;
+   unsigned long Length;
+   std::string Member;
+   
+   // Members from DirStream
+   virtual bool DoItem(Item &Itm,int &Fd) APT_OVERRIDE;
+   virtual bool Process(Item &Itm,const unsigned char *Data,
+			unsigned long long Size,unsigned long long Pos) APT_OVERRIDE;
+
+   // Helpers
+   bool Read(debDebFile &Deb);
+   bool TakeControl(const void *Data,unsigned long long Size);
+
+   MemControlExtract() : IsControl(false), Control(0), Length(0), Member("control") {};
+   MemControlExtract(std::string Member) : IsControl(false), Control(0), Length(0), Member(Member) {};
+   ~MemControlExtract() {delete [] Control;};   
+};
+									/*}}}*/
+
+#endif
diff --git a/apt-inst/dirstream.cc b/apt-inst/dirstream.cc
new file mode 100644
index 0000000..d6cf0ab
--- /dev/null
+++ b/apt-inst/dirstream.cc
@@ -0,0 +1,118 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Directory Stream 
+   
+   This class provides a simple basic extractor that can be used for
+   a number of purposes.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/error.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <apti18n.h>
+									/*}}}*/
+
+// DirStream::DoItem - Process an item					/*{{{*/
+// ---------------------------------------------------------------------
+/* This is a very simple extractor, it does not deal with things like
+   overwriting directories with files and so on. */
+bool pkgDirStream::DoItem(Item &Itm,int &Fd)
+{
+   switch (Itm.Type)
+   {
+      case Item::File:
+      {
+	 /* Open the output file, NDELAY is used to prevent this from 
+	    blowing up on device special files.. */
+	 int iFd = open(Itm.Name,O_NDELAY|O_WRONLY|O_CREAT|O_TRUNC|O_APPEND,
+		       Itm.Mode);
+	 if (iFd < 0)
+	    return _error->Errno("open",_("Failed to write file %s"),
+				 Itm.Name);
+	 
+	 // fchmod deals with umask and fchown sets the ownership
+	 if (fchmod(iFd,Itm.Mode) != 0)
+	 {
+	    close(iFd);
+	    return _error->Errno("fchmod",_("Failed to write file %s"), Itm.Name);
+	 }
+	 if (fchown(iFd,Itm.UID,Itm.GID) != 0 && errno != EPERM)
+	 {
+	    close(iFd);
+	    return _error->Errno("fchown",_("Failed to write file %s"), Itm.Name);
+	 }
+	 Fd = iFd;
+	 return true;
+      }
+      
+      case Item::HardLink:
+      case Item::SymbolicLink:
+      case Item::CharDevice:
+      case Item::BlockDevice:
+      case Item::Directory:
+      {
+	 struct stat Buf;
+	 // check if the dir is already there, if so return true
+	 if (stat(Itm.Name,&Buf) == 0)
+	 {
+	    if(S_ISDIR(Buf.st_mode))
+	       return true;
+	    // something else is there already, return false
+	    return false;
+	 }
+	 // nothing here, create the dir
+	 if(mkdir(Itm.Name,Itm.Mode) < 0)
+	    return false;
+	 return true;
+      }
+      case Item::FIFO:
+      break;
+   }
+   
+   return true;
+}
+									/*}}}*/
+// DirStream::FinishedFile - Finished processing a file			/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgDirStream::FinishedFile(Item &Itm,int Fd)
+{
+   if (Fd < 0)
+      return true;
+
+   /* Set the modification times. The only way it can fail is if someone
+      has futzed with our file, which is intolerable :> */
+   struct timeval times[2];
+   times[0].tv_sec = times[1].tv_sec = Itm.MTime;
+   times[0].tv_usec = times[1].tv_usec = 0;
+   if (utimes(Itm.Name, times) != 0)
+      _error->Errno("utimes", "Failed to set modification time for %s",Itm.Name);
+
+   if (close(Fd) != 0)
+      return _error->Errno("close",_("Failed to close file %s"),Itm.Name);
+   return true;
+}
+									/*}}}*/
+// DirStream::Fail - Failed processing a file				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgDirStream::Fail(Item &/*Itm*/, int Fd)
+{
+   if (Fd < 0)
+      return true;
+   
+   close(Fd);
+   return false;
+}
+									/*}}}*/
diff --git a/apt-inst/dirstream.h b/apt-inst/dirstream.h
new file mode 100644
index 0000000..0f0e348
--- /dev/null
+++ b/apt-inst/dirstream.h
@@ -0,0 +1,57 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Directory Stream 
+
+   When unpacking the contents of the archive are passed into a directory
+   stream class for analysis and processing. The class controls all aspects
+   of actually writing the directory stream from disk. The low level
+   archive handlers are only responsible for decoding the archive format
+   and sending events (via method calls) to the specified directory
+   stream.
+   
+   When unpacking a real file the archive handler is passed back a file 
+   handle to write the data to, this is to support strange 
+   archives+unpacking methods. If that fd is -1 then the file data is 
+   simply ignored.
+   
+   The provided defaults do the 'Right Thing' for a normal unpacking
+   process (ie 'tar')
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_DIRSTREAM_H
+#define PKGLIB_DIRSTREAM_H
+
+#include <apt-pkg/macros.h>
+
+class pkgDirStream
+{ 
+   public:
+
+   // All possible information about a component
+   struct Item
+   {
+      enum Type_t {File, HardLink, SymbolicLink, CharDevice, BlockDevice,
+	           Directory, FIFO} Type;
+      char *Name;
+      char *LinkTarget;
+      unsigned long Mode;
+      unsigned long UID;
+      unsigned long GID;
+      unsigned long long Size;
+      unsigned long MTime;
+      unsigned long Major;
+      unsigned long Minor;
+   };
+   
+   virtual bool DoItem(Item &Itm,int &Fd);
+   virtual bool Fail(Item &Itm,int Fd);
+   virtual bool FinishedFile(Item &Itm,int Fd);
+   virtual bool Process(Item &/*Itm*/,const unsigned char * /*Data*/,
+			unsigned long long /*Size*/,unsigned long long /*Pos*/) {return true;};
+   virtual ~pkgDirStream() {};   
+};
+
+#endif
diff --git a/apt-inst/dpkg-diffs.txt b/apt-inst/dpkg-diffs.txt
new file mode 100644
index 0000000..d161055
--- /dev/null
+++ b/apt-inst/dpkg-diffs.txt
@@ -0,0 +1,5 @@
+- Replacing directories with files
+  dpkg permits this with the weak condition that the directory is owned only
+  by the package. APT requires that the directory have no files that are not
+  owned by the package. Replaces are specifically not checked to prevent
+  file list corruption.
diff --git a/apt-inst/extract.cc b/apt-inst/extract.cc
new file mode 100644
index 0000000..35fa015
--- /dev/null
+++ b/apt-inst/extract.cc
@@ -0,0 +1,514 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Archive Extraction Directory Stream
+   
+   Extraction for each file is a bit of an involved process. Each object
+   undergoes an atomic backup, overwrite, erase sequence. First the
+   object is unpacked to '.dpkg.new' then the original is hardlinked to
+   '.dpkg.tmp' and finally the new object is renamed to overwrite the old
+   one. From an external perspective the file never ceased to exist.
+   After the archive has been successfully unpacked the .dpkg.tmp files
+   are erased. A failure causes all the .dpkg.tmp files to be restored.
+   
+   Decisions about unpacking go like this:
+      - Store the original filename in the file listing
+      - Resolve any diversions that would effect this file, all checks
+        below apply to the diverted name, not the real one.
+      - Resolve any symlinked configuration files.
+      - If the existing file does not exist then .dpkg-tmp is checked for.
+        [Note, this is reduced to only check if a file was expected to be
+         there]
+      - If the existing link/file is not a directory then it is replaced
+        regardless
+      - If the existing link/directory is being replaced by a directory then
+        absolutely nothing happens.
+      - If the existing link/directory is being replaced by a link then
+        absolutely nothing happens.
+      - If the existing link/directory is being replaced by a non-directory
+        then this will abort if the package is not the sole owner of the
+        directory. [Note, this is changed to not happen if the directory
+        non-empty - that is, it only includes files that are part of this
+        package - prevents removing user files accidentally.]
+      - If the non-directory exists in the listing database and it
+        does not belong to the current package then an overwrite condition
+        is invoked. 
+   
+   As we unpack we record the file list differences in the FL cache. If
+   we need to unroll the FL cache knows which files have been unpacked
+   and can undo. When we need to erase then it knows which files have not 
+   been unpacked.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/debversion.h>
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/extract.h>
+#include <apt-pkg/filelist.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/mmap.h>
+#include <apt-pkg/pkgcache.h>
+
+#include <iostream>
+#include <string>
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include <apti18n.h>
+									/*}}}*/
+using namespace std;
+
+static const char *TempExt = "dpkg-tmp";
+//static const char *NewExt = "dpkg-new";
+
+// Extract::pkgExtract - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+pkgExtract::pkgExtract(pkgFLCache &FLCache,pkgCache::VerIterator Ver) : 
+                       FLCache(FLCache), Ver(Ver)
+{
+   FLPkg = FLCache.GetPkg(Ver.ParentPkg().Name(),true);
+   if (FLPkg.end() == true)
+      return;
+   Debug = true;
+}
+									/*}}}*/
+// Extract::DoItem - Handle a single item from the stream		/*{{{*/
+// ---------------------------------------------------------------------
+/* This performs the setup for the extraction.. */
+bool pkgExtract::DoItem(Item &Itm, int &/*Fd*/)
+{
+   /* Strip any leading/trailing /s from the filename, then copy it to the
+      temp buffer and re-apply the leading / We use a class variable
+      to store the new filename for use by the three extraction funcs */
+   char *End = FileName+1;
+   const char *I = Itm.Name;
+   for (; *I != 0 && *I == '/'; I++);
+   *FileName = '/';
+   for (; *I != 0 && End < FileName + sizeof(FileName); I++, End++)
+      *End = *I;
+   if (End + 20 >= FileName + sizeof(FileName))
+      return _error->Error(_("The path %s is too long"),Itm.Name);   
+   for (; End > FileName && End[-1] == '/'; End--);
+   *End = 0;
+   Itm.Name = FileName;
+   
+   /* Lookup the file. Nde is the file [group] we are going to write to and
+      RealNde is the actual node we are manipulating. Due to diversions
+      they may be entirely different. */
+   pkgFLCache::NodeIterator Nde = FLCache.GetNode(Itm.Name,End,0,false,false);
+   pkgFLCache::NodeIterator RealNde = Nde;
+      
+   // See if the file is already in the file listing
+   unsigned long FileGroup = RealNde->File;
+   for (; RealNde.end() == false && FileGroup == RealNde->File; RealNde++)
+      if (RealNde.RealPackage() == FLPkg)
+	 break;
+
+   // Nope, create an entry
+   if (RealNde.end() == true)
+   {
+      RealNde = FLCache.GetNode(Itm.Name,End,FLPkg.Offset(),true,false);
+      if (RealNde.end() == true)
+	 return false;
+      RealNde->Flags |= pkgFLCache::Node::NewFile;
+   }
+
+   /* Check if this entry already was unpacked. The only time this should 
+      ever happen is if someone has hacked tar to support capabilities, in
+      which case this needs to be modified anyhow.. */
+   if ((RealNde->Flags & pkgFLCache::Node::Unpacked) ==
+       pkgFLCache::Node::Unpacked)
+      return _error->Error(_("Unpacking %s more than once"),Itm.Name);
+   
+   if (Nde.end() == true)
+      Nde = RealNde;
+
+   /* Consider a diverted file - We are not permitted to divert directories,
+      but everything else is fair game (including conf files!) */
+   if ((Nde->Flags & pkgFLCache::Node::Diversion) != 0)
+   {
+      if (Itm.Type == Item::Directory)
+	 return _error->Error(_("The directory %s is diverted"),Itm.Name);
+
+      /* A package overwriting a diversion target is just the same as 
+         overwriting a normally owned file and is checked for below in
+	 the overwrites mechanism */
+
+      /* If this package is trying to overwrite the target of a diversion, 
+         that is never, ever permitted */
+      pkgFLCache::DiverIterator Div = Nde.Diversion();
+      if (Div.DivertTo() == Nde)
+	 return _error->Error(_("The package is trying to write to the "
+			      "diversion target %s/%s"),Nde.DirN(),Nde.File());
+      
+      // See if it is us and we are following it in the right direction
+      if (Div->OwnerPkg != FLPkg.Offset() && Div.DivertFrom() == Nde)
+      {
+	 Nde = Div.DivertTo();
+	 End = FileName + snprintf(FileName,sizeof(FileName)-20,"%s/%s",
+				   Nde.DirN(),Nde.File());
+	 if (End <= FileName)
+	    return _error->Error(_("The diversion path is too long"));
+      }      
+   }
+   
+   // Deal with symlinks and conf files
+   if ((RealNde->Flags & pkgFLCache::Node::NewConfFile) == 
+       pkgFLCache::Node::NewConfFile)
+   {
+      string Res = flNoLink(Itm.Name);
+      if (Res.length() > sizeof(FileName))
+	 return _error->Error(_("The path %s is too long"),Res.c_str());
+      if (Debug == true)
+	 clog << "Followed conf file from " << FileName << " to " << Res << endl;
+      Itm.Name = strcpy(FileName,Res.c_str());      
+   }
+   
+   /* Get information about the existing file, and attempt to restore
+      a backup if it does not exist */
+   struct stat LExisting;
+   bool EValid = false;
+   if (lstat(Itm.Name,&LExisting) != 0)
+   {
+      // This is bad news.
+      if (errno != ENOENT)
+	 return _error->Errno("stat",_("Failed to stat %s"),Itm.Name);
+      
+      // See if we can recover the backup file
+      if (Nde.end() == false)
+      {
+	 char Temp[sizeof(FileName)];
+	 snprintf(Temp,sizeof(Temp),"%s.%s",Itm.Name,TempExt);
+	 if (rename(Temp,Itm.Name) != 0 && errno != ENOENT)
+	    return _error->Errno("rename",_("Failed to rename %s to %s"),
+				 Temp,Itm.Name);
+	 if (stat(Itm.Name,&LExisting) != 0)
+	 {
+	    if (errno != ENOENT)
+	       return _error->Errno("stat",_("Failed to stat %s"),Itm.Name);
+	 }	 
+	 else
+	    EValid = true;
+      }
+   }
+   else
+      EValid = true;
+   
+   /* If the file is a link we need to stat its destination, get the
+      existing file modes */
+   struct stat Existing = LExisting;
+   if (EValid == true && S_ISLNK(Existing.st_mode))
+   {
+      if (stat(Itm.Name,&Existing) != 0)
+      {
+	 if (errno != ENOENT)
+	    return _error->Errno("stat",_("Failed to stat %s"),Itm.Name);
+	 Existing = LExisting;
+      }      
+   }
+   
+   // We pretend a non-existing file looks like it is a normal file
+   if (EValid == false)
+      Existing.st_mode = S_IFREG;
+   
+   /* Okay, at this point 'Existing' is the stat information for the
+      real non-link file */
+   
+   /* The only way this can be a no-op is if a directory is being
+      replaced by a directory or by a link */
+   if (S_ISDIR(Existing.st_mode) != 0 && 
+       (Itm.Type == Item::Directory || Itm.Type == Item::SymbolicLink))
+      return true;
+      
+   /* Non-Directory being replaced by non-directory. We check for over
+      writes here. */
+   if (Nde.end() == false)
+   {
+      if (HandleOverwrites(Nde) == false)
+	 return false;
+   }
+   
+   /* Directory being replaced by a non-directory - this needs to see if
+      the package is the owner and then see if the directory would be
+      empty after the package is removed [ie no user files will be 
+      erased] */
+   if (S_ISDIR(Existing.st_mode) != 0)
+   {
+      if (CheckDirReplace(Itm.Name) == false)
+	 return _error->Error(_("The directory %s is being replaced by a non-directory"),Itm.Name);
+   }
+   
+   if (Debug == true)
+      clog << "Extract " << string(Itm.Name,End) << endl;
+/*   if (Count != 0)
+      return _error->Error(_("Done"));*/
+   
+   return true;
+}
+									/*}}}*/
+// Extract::Finished - Sequence finished, erase the temp files		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+APT_PURE bool pkgExtract::Finished()
+{
+   return true;
+}
+									/*}}}*/
+// Extract::Aborted - Sequence aborted, undo all our unpacking		/*{{{*/
+// ---------------------------------------------------------------------
+/* This undoes everything that was done by all calls to the DoItem method
+   and restores the File Listing cache to its original form. It bases its
+   actions on the flags value for each node in the cache. */
+bool pkgExtract::Aborted()
+{
+   if (Debug == true)
+      clog << "Aborted, backing out" << endl;
+   
+   pkgFLCache::NodeIterator Files = FLPkg.Files();
+   map_ptrloc *Last = &FLPkg->Files;
+   
+   /* Loop over all files, restore those that have been unpacked from their
+      dpkg-tmp entries */
+   while (Files.end() == false)
+   {
+      // Locate the hash bucket for the node and locate its group head
+      pkgFLCache::NodeIterator Nde(FLCache,FLCache.HashNode(Files));
+      for (; Nde.end() == false && Files->File != Nde->File; Nde++);
+      if (Nde.end() == true)
+	 return _error->Error(_("Failed to locate node in its hash bucket"));
+      
+      if (snprintf(FileName,sizeof(FileName)-20,"%s/%s",
+		   Nde.DirN(),Nde.File()) <= 0)
+	 return _error->Error(_("The path is too long"));
+      
+      // Deal with diversions
+      if ((Nde->Flags & pkgFLCache::Node::Diversion) != 0)
+      {
+	 pkgFLCache::DiverIterator Div = Nde.Diversion();
+	 
+	 // See if it is us and we are following it in the right direction
+	 if (Div->OwnerPkg != FLPkg.Offset() && Div.DivertFrom() == Nde)
+	 {
+	    Nde = Div.DivertTo();
+	    if (snprintf(FileName,sizeof(FileName)-20,"%s/%s",
+			 Nde.DirN(),Nde.File()) <= 0)
+	       return _error->Error(_("The diversion path is too long"));
+	 }
+      }      
+      
+      // Deal with overwrites+replaces
+      for (; Nde.end() == false && Files->File == Nde->File; Nde++)
+      {
+	 if ((Nde->Flags & pkgFLCache::Node::Replaced) == 
+	     pkgFLCache::Node::Replaced)
+	 {
+	    if (Debug == true)
+	       clog << "De-replaced " << FileName << " from " << Nde.RealPackage()->Name << endl;
+	    Nde->Flags &= ~pkgFLCache::Node::Replaced;
+	 }	 
+      }      
+      
+      // Undo the change in the filesystem
+      if (Debug == true)
+	 clog << "Backing out " << FileName;
+      
+      // Remove a new node
+      if ((Files->Flags & pkgFLCache::Node::NewFile) ==
+	 pkgFLCache::Node::NewFile)
+      {
+	 if (Debug == true)
+	    clog << " [new node]" << endl;
+	 pkgFLCache::Node *Tmp = Files;
+	 Files++;
+	 *Last = Tmp->NextPkg;
+	 Tmp->NextPkg = 0;
+
+	 FLCache.DropNode(Tmp - FLCache.NodeP);
+      }
+      else
+      {
+	 if (Debug == true)
+	    clog << endl;
+	 
+	 Last = &Files->NextPkg;
+	 Files++;
+      }      	 
+   }
+   
+   return true;
+}
+									/*}}}*/
+// Extract::Fail - Extraction of a file Failed				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgExtract::Fail(Item &Itm,int Fd)
+{
+   return pkgDirStream::Fail(Itm,Fd);
+}
+									/*}}}*/
+// Extract::FinishedFile - Finished a file				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool pkgExtract::FinishedFile(Item &Itm,int Fd)
+{
+   return pkgDirStream::FinishedFile(Itm,Fd);
+}
+									/*}}}*/
+// Extract::HandleOverwrites - See if a replaces covers this overwrite	/*{{{*/
+// ---------------------------------------------------------------------
+/* Check if the file is in a package that is being replaced by this 
+   package or if the file is being overwritten. Note that if the file
+   is really a directory but it has been erased from the filesystem 
+   this will fail with an overwrite message. This is a limitation of the
+   dpkg file information format. 
+ 
+   XX If a new package installs and another package replaces files in this
+   package what should we do? */
+bool pkgExtract::HandleOverwrites(pkgFLCache::NodeIterator Nde,
+				  bool DiverCheck)
+{
+   pkgFLCache::NodeIterator TmpNde = Nde;
+   unsigned long DiverOwner = 0;
+   unsigned long FileGroup = Nde->File;
+   for (; Nde.end() == false && FileGroup == Nde->File; Nde++)
+   {
+      if ((Nde->Flags & pkgFLCache::Node::Diversion) != 0)
+      {
+	 /* Store the diversion owner if this is the forward direction
+	    of the diversion */
+	 if (DiverCheck == true)
+	    DiverOwner = Nde.Diversion()->OwnerPkg;
+	 continue;
+      }
+
+      pkgFLCache::PkgIterator FPkg(FLCache,Nde.RealPackage());	 
+      if (FPkg.end() == true || FPkg == FLPkg)
+	 continue;
+      
+      /* This tests trips when we are checking a diversion to see
+         if something has already been diverted by this diversion */
+      if (FPkg.Offset() == DiverOwner)
+	 continue;
+
+      // Now see if this package matches one in a replace depends
+      pkgCache::DepIterator Dep = Ver.DependsList();
+      bool Ok = false;
+      for (; Dep.end() == false; ++Dep)
+      {
+	 if (Dep->Type != pkgCache::Dep::Replaces)
+	    continue;
+	 
+	 // Does the replaces apply to this package?
+	 if (strcmp(Dep.TargetPkg().Name(),FPkg.Name()) != 0)
+	     continue;
+	 
+	 /* Check the version for match. I do not think CurrentVer can be
+	    0 if we are here.. */
+	 pkgCache::PkgIterator Pkg = Dep.TargetPkg();
+	 if (Pkg->CurrentVer == 0)
+	 {
+	    _error->Warning(_("Overwrite package match with no version for %s"),Pkg.Name());
+	    continue;
+	 }
+
+	 // Replaces is met
+	 if (debVS.CheckDep(Pkg.CurrentVer().VerStr(),Dep->CompareOp,Dep.TargetVer()) == true)
+	 {
+	    if (Debug == true)
+	       clog << "Replaced file " << Nde.DirN() << '/' << Nde.File() << " from " << Pkg.Name() << endl;
+	    Nde->Flags |= pkgFLCache::Node::Replaced;
+	    Ok = true;
+	    break;
+	 }
+      }
+      
+      // Negative Hit
+      if (Ok == false)
+	 return _error->Error(_("File %s/%s overwrites the one in the package %s"),
+			      Nde.DirN(),Nde.File(),FPkg.Name());
+   }
+   
+   /* If this is a diversion we might have to recurse to process
+      the other side of it */
+   if ((TmpNde->Flags & pkgFLCache::Node::Diversion) != 0)
+   {
+      pkgFLCache::DiverIterator Div = TmpNde.Diversion();
+      if (Div.DivertTo() == TmpNde)
+	 return HandleOverwrites(Div.DivertFrom(),true);
+   }
+   
+   return true;
+}
+									/*}}}*/
+// Extract::CheckDirReplace - See if this directory can be erased	/*{{{*/
+// ---------------------------------------------------------------------
+/* If this directory is owned by a single package and that package is
+   replacing it with something non-directoryish then dpkg allows this.
+   We increase the requirement to be that the directory is non-empty after
+   the package is removed */
+bool pkgExtract::CheckDirReplace(string Dir,unsigned int Depth)
+{
+   // Looping?
+   if (Depth > 40)
+      return false;
+   
+   if (Dir[Dir.size() - 1] != '/')
+      Dir += '/';
+   
+   DIR *D = opendir(Dir.c_str());
+   if (D == 0)
+      return _error->Errno("opendir",_("Unable to read %s"),Dir.c_str());
+
+   string File;
+   for (struct dirent *Dent = readdir(D); Dent != 0; Dent = readdir(D))
+   {
+      // Skip some files
+      if (strcmp(Dent->d_name,".") == 0 ||
+	  strcmp(Dent->d_name,"..") == 0)
+	 continue;
+      
+      // Look up the node
+      File = Dir + Dent->d_name;
+      pkgFLCache::NodeIterator Nde = FLCache.GetNode(File.c_str(),
+						     File.c_str() + File.length(),0,false,false);
+
+      // The file is not owned by this package
+      if (Nde.end() != false || Nde.RealPackage() != FLPkg)
+      {
+	 closedir(D);
+	 return false;
+      }
+      
+      // See if it is a directory
+      struct stat St;
+      if (lstat(File.c_str(),&St) != 0)
+      {
+	 closedir(D);
+	 return _error->Errno("lstat",_("Unable to stat %s"),File.c_str());
+      }
+      
+      // Recurse down directories
+      if (S_ISDIR(St.st_mode) != 0)
+      {
+	 if (CheckDirReplace(File,Depth + 1) == false)
+	 {
+	    closedir(D);
+	    return false;
+	 }
+      }      
+   }
+   
+   // No conflicts
+   closedir(D);
+   return true;
+}
+									/*}}}*/
diff --git a/apt-inst/extract.h b/apt-inst/extract.h
new file mode 100644
index 0000000..4b4c8d7
--- /dev/null
+++ b/apt-inst/extract.h
@@ -0,0 +1,49 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Archive Extraction Directory Stream
+   
+   This Directory Stream implements extraction of an archive into the
+   filesystem. It makes the choices on what files should be unpacked and
+   replaces as well as guiding the actual unpacking.
+   
+   When the unpacking sequence is completed one of the two functions,
+   Finished or Aborted must be called.
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_EXTRACT_H
+#define PKGLIB_EXTRACT_H
+
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/filelist.h>
+#include <apt-pkg/pkgcache.h>
+
+#include <string>
+
+class pkgExtract : public pkgDirStream
+{
+   pkgFLCache &FLCache;
+   pkgCache::VerIterator Ver;
+   pkgFLCache::PkgIterator FLPkg;
+   char FileName[1024];
+   bool Debug;
+   
+   bool HandleOverwrites(pkgFLCache::NodeIterator Nde,
+			 bool DiverCheck = false);
+   bool CheckDirReplace(std::string Dir,unsigned int Depth = 0);
+   
+   public:
+   
+   virtual bool DoItem(Item &Itm,int &Fd) APT_OVERRIDE;
+   virtual bool Fail(Item &Itm,int Fd) APT_OVERRIDE;
+   virtual bool FinishedFile(Item &Itm,int Fd) APT_OVERRIDE;
+
+   bool Finished();
+   bool Aborted();
+   
+   pkgExtract(pkgFLCache &FLCache,pkgCache::VerIterator Ver);
+};
+
+#endif
diff --git a/apt-inst/filelist.cc b/apt-inst/filelist.cc
new file mode 100644
index 0000000..44b97d0
--- /dev/null
+++ b/apt-inst/filelist.cc
@@ -0,0 +1,586 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   File Listing - Manages a Cache of File -> Package names.
+
+   Diversions add some significant complexity to the system. To keep
+   storage space down in the very special case of a diverted file no
+   extra bytes are allocated in the Node structure. Instead a diversion
+   is inserted directly into the hash table and its flag bit set. Every
+   lookup for that filename will always return the diversion.
+   
+   The hash buckets are stored in sorted form, with diversions having 
+   the highest sort order. Identical files are assigned the same file
+   pointer, thus after a search all of the nodes owning that file can be
+   found by iterating down the bucket.
+   
+   Re-updates of diversions (another extremely special case) are done by
+   marking all diversions as untouched, then loading the entire diversion
+   list again, touching each diversion and then finally going back and
+   releasing all untouched diversions. It is assumed that the diversion
+   table will always be quite small and be a very irregular case.
+
+   Diversions that are user-installed are represented by a package with
+   an empty name string.
+
+   Conf files are handled like diversions by changing the meaning of the
+   Pointer field to point to a conf file entry - again to reduce over
+   head for a special case.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/error.h>
+#include <apt-pkg/filelist.h>
+#include <apt-pkg/mmap.h>
+#include <apt-pkg/strutl.h>
+
+#include <iostream>
+#include <string.h>
+#include <apti18n.h>
+									/*}}}*/
+
+using namespace std;
+
+// FlCache::Header::Header - Constructor				/*{{{*/
+// ---------------------------------------------------------------------
+/* Initialize the header variables. These are the defaults used when
+   creating new caches */
+pkgFLCache::Header::Header()
+{
+   Signature = 0xEA3F1295;
+   
+   /* Whenever the structures change the major version should be bumped,
+    whenever the generator changes the minor version should be bumped. */
+   MajorVersion = 1;
+   MinorVersion = 0;
+   Dirty = true;
+   
+   HeaderSz = sizeof(pkgFLCache::Header);
+   NodeSz = sizeof(pkgFLCache::Node);
+   DirSz = sizeof(pkgFLCache::Directory);
+   PackageSz = sizeof(pkgFLCache::Package);
+   DiversionSz = sizeof(pkgFLCache::Diversion);
+   ConfFileSz = sizeof(pkgFLCache::ConfFile);
+      
+   NodeCount = 0;
+   DirCount = 0;
+   PackageCount = 0;
+   DiversionCount = 0;
+   ConfFileCount = 0;
+   HashSize = 1 << 14;
+
+   FileHash = 0;
+   DirTree = 0;
+   Packages = 0;
+   Diversions = 0;
+   UniqNodes = 0;
+   memset(Pools,0,sizeof(Pools));
+}
+									/*}}}*/
+// FLCache::Header::CheckSizes - Check if the two headers have same *sz	/*{{{*/
+// ---------------------------------------------------------------------
+/* Compare to make sure we are matching versions */
+APT_PURE bool pkgFLCache::Header::CheckSizes(Header &Against) const
+{
+   if (HeaderSz == Against.HeaderSz &&
+       NodeSz == Against.NodeSz &&
+       DirSz == Against.DirSz &&
+       DiversionSz == Against.DiversionSz &&
+       PackageSz == Against.PackageSz &&
+       ConfFileSz == Against.ConfFileSz)
+            return true;
+      return false;
+}
+									/*}}}*/
+
+// FLCache::pkgFLCache - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* If this is a new cache then a new header and hash table are instantaited
+   otherwise the existing ones are mearly attached */
+pkgFLCache::pkgFLCache(DynamicMMap &Map) : Map(Map)
+{
+   if (_error->PendingError() == true)
+      return;
+
+   LastTreeLookup = 0;
+   LastLookupSize = 0;
+   
+   // Apply the typecasts
+   HeaderP = (Header *)Map.Data();
+   NodeP = (Node *)Map.Data();
+   DirP = (Directory *)Map.Data();
+   DiverP = (Diversion *)Map.Data();
+   PkgP = (Package *)Map.Data();
+   ConfP = (ConfFile *)Map.Data();
+   StrP = (char *)Map.Data();
+   AnyP = (unsigned char *)Map.Data();
+   
+   // New mapping, create the basic cache structures
+   if (Map.Size() == 0)
+   {
+      Map.RawAllocate(sizeof(pkgFLCache::Header));
+      *HeaderP = pkgFLCache::Header();
+      HeaderP->FileHash = Map.RawAllocate(sizeof(pkgFLCache::Node)*HeaderP->HashSize,
+					  sizeof(pkgFLCache::Node))/sizeof(pkgFLCache::Node);
+   }
+
+   FileHash = NodeP + HeaderP->FileHash;
+   
+   // Setup the dynamic map manager
+   HeaderP->Dirty = true;
+   Map.Sync(0,sizeof(pkgFLCache::Header));
+   Map.UsePools(*HeaderP->Pools,sizeof(HeaderP->Pools)/sizeof(HeaderP->Pools[0]));
+}
+									/*}}}*/
+// FLCache::TreeLookup - Perform a lookup in a generic tree		/*{{{*/
+// ---------------------------------------------------------------------
+/* This is a simple generic tree lookup. The first three entries of
+   the Directory structure are used as a template, but any other similar
+   structure could be used in it's place. */
+map_ptrloc pkgFLCache::TreeLookup(map_ptrloc *Base,const char *Text,
+				  const char *TextEnd,unsigned long Size,
+				  unsigned int *Count,bool Insert)
+{       
+   pkgFLCache::Directory *Dir;
+   
+   // Check our last entry cache
+   if (LastTreeLookup != 0 && LastLookupSize == Size)
+   {
+      Dir = (pkgFLCache::Directory *)(AnyP + LastTreeLookup*Size);
+      if (stringcmp(Text,TextEnd,StrP + Dir->Name) == 0)
+	 return LastTreeLookup; 
+   }   
+   
+   while (1)
+   {
+      // Allocate a new one
+      if (*Base == 0)
+      {
+	 if (Insert == false)
+	    return 0;
+	 
+	 *Base = Map.Allocate(Size);
+	 if (*Base == 0)
+	    return 0;
+	 
+	 (*Count)++;
+	 Dir = (pkgFLCache::Directory *)(AnyP + *Base*Size);
+	 Dir->Name = Map.WriteString(Text,TextEnd - Text);
+	 LastTreeLookup = *Base;
+	 LastLookupSize = Size;
+	 return *Base;
+      }
+      
+      // Compare this node
+      Dir = (pkgFLCache::Directory *)(AnyP + *Base*Size);
+      int Res = stringcmp(Text,TextEnd,StrP + Dir->Name);
+      if (Res == 0)
+      {
+	 LastTreeLookup = *Base;
+	 LastLookupSize = Size;
+	 return *Base;
+      }
+      
+      if (Res > 0)
+	 Base = &Dir->Left;
+      if (Res < 0)
+	 Base = &Dir->Right;
+   }
+}
+									/*}}}*/
+// FLCache::PrintTree - Print out a tree				/*{{{*/
+// ---------------------------------------------------------------------
+/* This is a simple generic tree dumper, meant for debugging. */
+void pkgFLCache::PrintTree(map_ptrloc Base,unsigned long Size)
+{
+   if (Base == 0)
+      return;
+   
+   pkgFLCache::Directory *Dir = (pkgFLCache::Directory *)(AnyP + Base*Size);
+   PrintTree(Dir->Left,Size);
+   cout << (StrP + Dir->Name) << endl;
+   PrintTree(Dir->Right,Size);
+}
+									/*}}}*/
+// FLCache::GetPkg - Get a package pointer				/*{{{*/
+// ---------------------------------------------------------------------
+/* Locate a package by name in it's tree, this is just a wrapper for
+   TreeLookup */
+pkgFLCache::PkgIterator pkgFLCache::GetPkg(const char *Name,const char *NameEnd,
+					   bool Insert)
+{
+   if (NameEnd == 0)
+      NameEnd = Name + strlen(Name);
+   
+   map_ptrloc Pos = TreeLookup(&HeaderP->Packages,Name,NameEnd,
+			       sizeof(pkgFLCache::Package),
+			       &HeaderP->PackageCount,Insert);
+   if (Pos == 0)
+      return pkgFLCache::PkgIterator();
+   return pkgFLCache::PkgIterator(*this,PkgP + Pos);
+}
+									/*}}}*/
+// FLCache::GetNode - Get the node associated with the filename		/*{{{*/
+// ---------------------------------------------------------------------
+/* Lookup a node in the hash table. If Insert is true then a new node is
+   always inserted. The hash table can have multiple instances of a
+   single name available. A search returns the first. It is important
+   that additions for the same name insert after the first entry of
+   the name group. */
+pkgFLCache::NodeIterator pkgFLCache::GetNode(const char *Name,
+					     const char *NameEnd,
+					     map_ptrloc Loc,
+					     bool Insert,bool Divert)
+{
+   // Split the name into file and directory, hashing as it is copied 
+   const char *File = Name;
+   unsigned long HashPos = 0;
+   for (const char *I = Name; I < NameEnd; I++)
+   {
+      HashPos = 1637*HashPos + *I;
+      if (*I == '/')
+	 File = I;
+   }
+   
+   // Search for it
+   Node *Hash = NodeP + HeaderP->FileHash + (HashPos % HeaderP->HashSize);
+   int Res = 0;
+   map_ptrloc FilePtr = 0;
+   while (Hash->Pointer != 0)
+   {
+      // Compare
+      Res = stringcmp(File+1,NameEnd,StrP + Hash->File);
+      if (Res == 0)
+	 Res = stringcmp(Name,File,StrP + DirP[Hash->Dir].Name);
+      
+      // Diversion?
+      if (Res == 0 && Insert == true)
+      {
+	 /* Dir and File match exactly, we need to reuse the file name
+	    when we link it in */
+	 FilePtr = Hash->File;
+	 Res = Divert - ((Hash->Flags & Node::Diversion) == Node::Diversion);
+      }
+      
+      // Is a match
+      if (Res == 0)
+      {
+	 if (Insert == false)
+	    return NodeIterator(*this,Hash);
+	 
+	 // Only one diversion per name!
+	 if (Divert == true)
+	    return NodeIterator(*this,Hash);
+	 break;
+      }
+            
+      // Out of sort order
+      if (Res > 0)
+	 break;
+      
+      if (Hash->Next != 0)
+	 Hash = NodeP + Hash->Next;
+      else
+	 break;
+   }   
+   
+   // Fail, not found
+   if (Insert == false)
+      return NodeIterator(*this);
+
+   // Find a directory node
+   map_ptrloc Dir = TreeLookup(&HeaderP->DirTree,Name,File,
+			       sizeof(pkgFLCache::Directory),
+			       &HeaderP->DirCount,true);
+   if (Dir == 0)
+      return NodeIterator(*this);
+
+   // Allocate a new node
+   if (Hash->Pointer != 0)
+   {
+      // Overwrite or append
+      if (Res > 0)
+      {
+	 Node *Next = NodeP + Map.Allocate(sizeof(*Hash));
+	 if (Next == NodeP)
+	    return NodeIterator(*this);
+	 *Next = *Hash;
+	 Hash->Next = Next - NodeP;
+      }
+      else
+      {
+	 unsigned long NewNext = Map.Allocate(sizeof(*Hash));
+	 if (NewNext == 0)
+	    return NodeIterator(*this);
+	 NodeP[NewNext].Next = Hash->Next;
+	 Hash->Next = NewNext;
+	 Hash = NodeP + Hash->Next;
+      }      
+   }      
+   
+   // Insert into the new item
+   Hash->Dir = Dir;
+   Hash->Pointer = Loc;
+   Hash->Flags = 0;
+   if (Divert == true)
+      Hash->Flags |= Node::Diversion;
+   
+   if (FilePtr != 0)
+      Hash->File = FilePtr;
+   else
+   {
+      HeaderP->UniqNodes++;
+      Hash->File = Map.WriteString(File+1,NameEnd - File-1);
+   }
+   
+   // Link the node to the package list
+   if (Divert == false && Loc == 0)
+   {
+      Hash->Next = PkgP[Loc].Files;
+      PkgP[Loc].Files = Hash - NodeP;
+   }
+   
+   HeaderP->NodeCount++;
+   return NodeIterator(*this,Hash);
+}
+									/*}}}*/
+// FLCache::HashNode - Return the hash bucket for the node		/*{{{*/
+// ---------------------------------------------------------------------
+/* This is one of two hashing functions. The other is inlined into the
+   GetNode routine. */
+APT_PURE pkgFLCache::Node *pkgFLCache::HashNode(NodeIterator const &Nde)
+{
+   // Hash the node
+   unsigned long HashPos = 0;
+   for (const char *I = Nde.DirN(); *I != 0; I++)
+      HashPos = 1637*HashPos + *I;
+   HashPos = 1637*HashPos + '/';
+   for (const char *I = Nde.File(); *I != 0; I++)
+      HashPos = 1637*HashPos + *I;
+   return NodeP + HeaderP->FileHash + (HashPos % HeaderP->HashSize);
+}
+									/*}}}*/
+// FLCache::DropNode - Drop a node from the hash table			/*{{{*/
+// ---------------------------------------------------------------------
+/* This erases a node from the hash table. Note that this does not unlink
+   the node from the package linked list. */
+void pkgFLCache::DropNode(map_ptrloc N)
+{
+   if (N == 0)
+      return;
+   
+   NodeIterator Nde(*this,NodeP + N);
+   
+   if (Nde->NextPkg != 0)
+      _error->Warning(_("DropNode called on still linked node"));
+   
+   // Locate it in the hash table
+   Node *Last = 0;
+   Node *Hash = HashNode(Nde);
+   while (Hash->Pointer != 0)
+   {
+      // Got it
+      if (Hash == Nde)
+      {
+	 // Top of the bucket..
+	 if (Last == 0)
+	 {
+	    Hash->Pointer = 0;
+	    if (Hash->Next == 0)
+	       return;
+	    *Hash = NodeP[Hash->Next];
+	    // Release Hash->Next
+	    return;
+	 }
+	 Last->Next = Hash->Next;
+	 // Release Hash
+	 return;
+      }
+      
+      Last = Hash;
+      if (Hash->Next != 0)
+	 Hash = NodeP + Hash->Next;
+      else
+	 break;
+   }   
+ 
+   _error->Error(_("Failed to locate the hash element!"));
+}
+									/*}}}*/
+// FLCache::BeginDiverLoad - Start reading new diversions		/*{{{*/
+// ---------------------------------------------------------------------
+/* Tag all the diversions as untouched */
+void pkgFLCache::BeginDiverLoad()
+{
+   for (DiverIterator I = DiverBegin(); I.end() == false; I++)
+      I->Flags = 0;
+}
+									/*}}}*/
+// FLCache::FinishDiverLoad - Finish up a new diversion load		/*{{{*/
+// ---------------------------------------------------------------------
+/* This drops any untouched diversions. In effect removing any diversions
+   that where not loaded (ie missing from the diversion file) */
+void pkgFLCache::FinishDiverLoad()
+{
+   map_ptrloc *Cur = &HeaderP->Diversions;
+   while (*Cur != 0) 
+   {
+      Diversion *Div = DiverP + *Cur;
+      if ((Div->Flags & Diversion::Touched) == Diversion::Touched)
+      {
+	 Cur = &Div->Next;
+	 continue;
+      }
+   
+      // Purge!
+      DropNode(Div->DivertTo);
+      DropNode(Div->DivertFrom);
+      *Cur = Div->Next;
+   }
+}
+									/*}}}*/
+// FLCache::AddDiversion - Add a new diversion				/*{{{*/
+// ---------------------------------------------------------------------
+/* Add a new diversion to the diverion tables and make sure that it is
+   unique and non-chaining. */
+bool pkgFLCache::AddDiversion(PkgIterator const &Owner,
+			      const char *From,const char *To)
+{   
+   /* Locate the two hash nodes we are going to manipulate. If there
+      are pre-existing diversions then they will be returned */
+   NodeIterator FromN = GetNode(From,From+strlen(From),0,true,true);
+   NodeIterator ToN = GetNode(To,To+strlen(To),0,true,true);
+   if (FromN.end() == true || ToN.end() == true)
+      return _error->Error(_("Failed to allocate diversion"));
+
+   // Should never happen
+   if ((FromN->Flags & Node::Diversion) != Node::Diversion ||
+       (ToN->Flags & Node::Diversion) != Node::Diversion)
+      return _error->Error(_("Internal error in AddDiversion"));
+
+   // Now, try to reclaim an existing diversion..
+   map_ptrloc Diver = 0;
+   if (FromN->Pointer != 0)
+      Diver = FromN->Pointer;
+  
+   /* Make sure from and to point to the same diversion, if they don't
+      then we are trying to intermix diversions - very bad */
+   if (ToN->Pointer != 0 && ToN->Pointer != Diver)
+   {
+      // It could be that the other diversion is no longer in use
+      if ((DiverP[ToN->Pointer].Flags & Diversion::Touched) == Diversion::Touched)	 
+	 return _error->Error(_("Trying to overwrite a diversion, %s -> %s and %s/%s"),
+			      From,To,ToN.File(),ToN.Dir().Name());
+      
+      // We can erase it.
+      Diversion *Div = DiverP + ToN->Pointer;
+      ToN->Pointer = 0;
+      
+      if (Div->DivertTo == ToN.Offset())
+	 Div->DivertTo = 0;
+      if (Div->DivertFrom == ToN.Offset())
+	 Div->DivertFrom = 0;
+      
+      // This diversion will be cleaned up by FinishDiverLoad
+   }
+   
+   // Allocate a new diversion
+   if (Diver == 0)
+   {
+      Diver = Map.Allocate(sizeof(Diversion));
+      if (Diver == 0)
+	 return false;
+      DiverP[Diver].Next = HeaderP->Diversions;
+      HeaderP->Diversions = Diver;
+      HeaderP->DiversionCount++;
+   }
+
+   // Can only have one diversion of the same files
+   Diversion *Div = DiverP + Diver;
+   if ((Div->Flags & Diversion::Touched) == Diversion::Touched)
+      return _error->Error(_("Double add of diversion %s -> %s"),From,To);
+   
+   // Setup the From/To links
+   if (Div->DivertFrom != FromN.Offset() && Div->DivertFrom != ToN.Offset())
+      DropNode(Div->DivertFrom);
+   Div->DivertFrom = FromN.Offset();
+   if (Div->DivertTo != FromN.Offset() && Div->DivertTo != ToN.Offset())
+      DropNode(Div->DivertTo);
+   Div->DivertTo = ToN.Offset();
+   
+   // Link it to the two nodes
+   FromN->Pointer = Diver;
+   ToN->Pointer = Diver;
+   
+   // And the package
+   Div->OwnerPkg = Owner.Offset();
+   Div->Flags |= Diversion::Touched;
+   
+   return true;
+}
+									/*}}}*/
+// FLCache::AddConfFile - Add a new configuration file			/*{{{*/
+// ---------------------------------------------------------------------
+/* This simply adds a new conf file node to the hash table. This is only
+   used by the status file reader. It associates a hash with each conf
+   file entry that exists in the status file and the list file for 
+   the proper package. Duplicate conf files (across packages) are left
+   up to other routines to deal with. */
+bool pkgFLCache::AddConfFile(const char *Name,const char *NameEnd,
+			     PkgIterator const &Owner,
+			     const unsigned char *Sum)
+{
+   NodeIterator Nde = GetNode(Name,NameEnd,0,false,false);
+   if (Nde.end() == true)
+      return true;
+   
+   unsigned long File = Nde->File;
+   for (; Nde->File == File && Nde.end() == false; Nde++)
+   {
+      if (Nde.RealPackage() != Owner)
+	 continue;
+
+      if ((Nde->Flags & Node::ConfFile) == Node::ConfFile)
+	 return _error->Error(_("Duplicate conf file %s/%s"),Nde.DirN(),Nde.File());
+			      
+      // Allocate a new conf file structure
+      map_ptrloc Conf = Map.Allocate(sizeof(ConfFile));
+      if (Conf == 0)
+	 return false;
+      ConfP[Conf].OwnerPkg = Owner.Offset();
+      memcpy(ConfP[Conf].MD5,Sum,sizeof(ConfP[Conf].MD5));
+      
+      Nde->Pointer = Conf;
+      Nde->Flags |= Node::ConfFile;
+      return true;
+   }
+      
+   /* This means the conf file has been replaced, but the entry in the 
+      status file was not updated */
+   return true;
+}
+									/*}}}*/
+
+// NodeIterator::RealPackage - Return the package for this node		/*{{{*/
+// ---------------------------------------------------------------------
+/* Since the package pointer is indirected in all sorts of interesting ways
+   this is used to get a pointer to the owning package */
+APT_PURE pkgFLCache::Package *pkgFLCache::NodeIterator::RealPackage() const
+{
+   if (Nde->Pointer == 0)
+      return 0;
+   
+   if ((Nde->Flags & Node::ConfFile) == Node::ConfFile)
+      return Owner->PkgP + Owner->ConfP[Nde->Pointer].OwnerPkg;
+
+   // Diversions are ignored
+   if ((Nde->Flags & Node::Diversion) == Node::Diversion)
+      return 0;
+   
+   return Owner->PkgP + Nde->Pointer;
+}
+									/*}}}*/
diff --git a/apt-inst/filelist.h b/apt-inst/filelist.h
new file mode 100644
index 0000000..7fe43de
--- /dev/null
+++ b/apt-inst/filelist.h
@@ -0,0 +1,312 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   File Listing - Manages a Cache of File -> Package names.
+
+   This is identical to the Package cache, except that the generator 
+   (which is much simpler) is integrated directly into the main class, 
+   and it has been designed to handle live updates.
+   
+   The storage content of the class is maintained in a memory map and is
+   written directly to the file system. Performance is traded against 
+   space to give something that performs well and remains small.
+   The average per file usage is 32 bytes which yields about a meg every
+   36k files. Directory paths are collected into a binary tree and stored
+   only once, this offsets the cost of the hash nodes enough to keep 
+   memory usage slightly less than the sum of the filenames.
+ 
+   The file names are stored into a fixed size chained hash table that is
+   linked to the package name and to the directory component. 
+
+   Each file node has a set of associated flags that indicate the current
+   state of the file.
+   
+   ##################################################################### */
+									/*}}}*/
+#ifndef PKGLIB_FILELIST_H
+#define PKGLIB_FILELIST_H
+
+#include <apt-pkg/mmap.h>
+
+#include <cstring>
+#include <string>
+
+class pkgFLCache
+{
+   public:
+   struct Header;
+   struct Node;
+   struct Directory;
+   struct Package;
+   struct Diversion;
+   struct ConfFile;
+
+   class NodeIterator;
+   class DirIterator;
+   class PkgIterator;
+   class DiverIterator;
+
+   protected:
+   std::string CacheFile;
+   DynamicMMap &Map;
+   map_ptrloc LastTreeLookup;
+   unsigned long LastLookupSize;
+
+   // Helpers for the addition algorithms
+   map_ptrloc TreeLookup(map_ptrloc *Base,const char *Text,const char *TextEnd,
+			 unsigned long Size,unsigned int *Count = 0,
+			 bool Insert = false);
+
+   public:
+
+   // Pointers to the arrays of items
+   Header *HeaderP;
+   Node *NodeP;
+   Directory *DirP;
+   Package *PkgP;
+   Diversion *DiverP;
+   ConfFile *ConfP;
+   char *StrP;
+   unsigned char *AnyP;
+
+   // Quick accessors
+   Node *FileHash;
+
+   // Accessors
+   Header &Head() {return *HeaderP;};
+   void PrintTree(map_ptrloc Base,unsigned long Size);
+
+   // Add/Find things
+   PkgIterator GetPkg(const char *Name,const char *End,bool Insert);
+   inline PkgIterator GetPkg(const char *Name,bool Insert);
+   NodeIterator GetNode(const char *Name,
+			const char *NameEnd,
+			map_ptrloc Loc,
+			bool Insert,bool Divert);
+   Node *HashNode(NodeIterator const &N);
+   void DropNode(map_ptrloc Node);
+
+   inline DiverIterator DiverBegin();
+
+   // Diversion control
+   void BeginDiverLoad();
+   void FinishDiverLoad();
+   bool AddDiversion(PkgIterator const &Owner,const char *From,
+		     const char *To);
+   bool AddConfFile(const char *Name,const char *NameEnd,
+		    PkgIterator const &Owner,const unsigned char *Sum);
+
+   pkgFLCache(DynamicMMap &Map);
+//   ~pkgFLCache();
+};
+
+struct pkgFLCache::Header
+{
+   // Signature information
+   unsigned long Signature;
+   short MajorVersion;
+   short MinorVersion;
+   bool Dirty;
+
+   // Size of structure values
+   unsigned HeaderSz;
+   unsigned NodeSz;
+   unsigned DirSz;
+   unsigned PackageSz;
+   unsigned DiversionSz;
+   unsigned ConfFileSz;
+
+   // Structure Counts;
+   unsigned int NodeCount;
+   unsigned int DirCount;
+   unsigned int PackageCount;
+   unsigned int DiversionCount;
+   unsigned int ConfFileCount;
+   unsigned int HashSize;
+   unsigned long UniqNodes;
+
+   // Offsets
+   map_ptrloc FileHash;
+   map_ptrloc DirTree;
+   map_ptrloc Packages;
+   map_ptrloc Diversions;
+
+   /* Allocation pools, there should be one of these for each structure
+      excluding the header */
+   DynamicMMap::Pool Pools[5];
+
+   bool CheckSizes(Header &Against) const;
+   Header();
+};
+
+/* The bit field is used to advoid incurring an extra 4 bytes x 40000,
+   Pointer is the most infrequently used member of the structure */
+struct pkgFLCache::Node
+{
+   map_ptrloc Dir;            // Dir
+   map_ptrloc File;           // String
+   unsigned Pointer:24;       // Package/Diversion/ConfFile
+   unsigned Flags:8;          // Package
+   map_ptrloc Next;           // Node
+   map_ptrloc NextPkg;        // Node
+
+   enum Flags {Diversion = (1<<0),ConfFile = (1<<1),
+               NewConfFile = (1<<2),NewFile = (1<<3),
+               Unpacked = (1<<4),Replaced = (1<<5)};
+};
+
+struct pkgFLCache::Directory
+{
+   map_ptrloc Left;           // Directory
+   map_ptrloc Right;          // Directory
+   map_ptrloc Name;           // String
+};
+
+struct pkgFLCache::Package
+{
+   map_ptrloc Left;           // Package
+   map_ptrloc Right;          // Package
+   map_ptrloc Name;           // String
+   map_ptrloc Files;          // Node
+};
+
+struct pkgFLCache::Diversion
+{
+   map_ptrloc OwnerPkg;       // Package
+   map_ptrloc DivertFrom;     // Node
+   map_ptrloc DivertTo;       // String
+
+   map_ptrloc Next;           // Diversion
+   unsigned long Flags;
+
+   enum Flags {Touched = (1<<0)};
+};
+
+struct pkgFLCache::ConfFile
+{
+   map_ptrloc OwnerPkg;       // Package
+   unsigned char MD5[16];
+};
+
+class pkgFLCache::PkgIterator
+{
+   Package *Pkg;
+   pkgFLCache *Owner;
+
+   public:
+
+   inline bool end() const {return Owner == 0 || Pkg == Owner->PkgP?true:false;}
+
+   // Accessors
+   inline Package *operator ->() {return Pkg;}
+   inline Package const *operator ->() const {return Pkg;}
+   inline Package const &operator *() const {return *Pkg;}
+   inline operator Package *() {return Pkg == Owner->PkgP?0:Pkg;}
+   inline operator Package const *() const {return Pkg == Owner->PkgP?0:Pkg;}
+
+   inline unsigned long Offset() const {return Pkg - Owner->PkgP;}
+   inline const char *Name() const {return Pkg->Name == 0?0:Owner->StrP + Pkg->Name;}
+   inline pkgFLCache::NodeIterator Files() const;
+
+   PkgIterator() : Pkg(0), Owner(0) {}
+   PkgIterator(pkgFLCache &Owner,Package *Trg) : Pkg(Trg), Owner(&Owner) {}
+};
+
+class pkgFLCache::DirIterator
+{
+   Directory *Dir;
+   pkgFLCache *Owner;
+
+   public:
+
+   // Accessors
+   inline Directory *operator ->() {return Dir;}
+   inline Directory const *operator ->() const {return Dir;}
+   inline Directory const &operator *() const {return *Dir;}
+   inline operator Directory *() {return Dir == Owner->DirP?0:Dir;}
+   inline operator Directory const *() const {return Dir == Owner->DirP?0:Dir;}
+
+   inline const char *Name() const {return Dir->Name == 0?0:Owner->StrP + Dir->Name;}
+
+   DirIterator() : Dir(0), Owner(0) {}
+   DirIterator(pkgFLCache &Owner,Directory *Trg) : Dir(Trg), Owner(&Owner) {}
+};
+
+class pkgFLCache::DiverIterator
+{
+   Diversion *Diver;
+   pkgFLCache *Owner;
+
+   public:
+
+   // Iteration
+   void operator ++(int) {if (Diver != Owner->DiverP) Diver = Owner->DiverP + Diver->Next;}
+   inline void operator ++() {operator ++(0);}
+   inline bool end() const {return Owner == 0 || Diver == Owner->DiverP;}
+
+   // Accessors
+   inline Diversion *operator ->() {return Diver;}
+   inline Diversion const *operator ->() const {return Diver;}
+   inline Diversion const &operator *() const {return *Diver;}
+   inline operator Diversion *() {return Diver == Owner->DiverP?0:Diver;}
+   inline operator Diversion const *() const {return Diver == Owner->DiverP?0:Diver;}
+
+   inline PkgIterator OwnerPkg() const {return PkgIterator(*Owner,Owner->PkgP + Diver->OwnerPkg);}
+   inline NodeIterator DivertFrom() const;
+   inline NodeIterator DivertTo() const;
+
+   DiverIterator() : Diver(0), Owner(0) {};
+   DiverIterator(pkgFLCache &Owner,Diversion *Trg) : Diver(Trg), Owner(&Owner) {}
+};
+
+class pkgFLCache::NodeIterator
+{
+   Node *Nde;
+   enum {NdePkg, NdeHash} Type;
+   pkgFLCache *Owner;
+
+   public:
+
+   // Iteration
+   void operator ++(int) {if (Nde != Owner->NodeP) Nde = Owner->NodeP +
+	 (Type == NdePkg?Nde->NextPkg:Nde->Next);}
+   inline void operator ++() {operator ++(0);}
+   inline bool end() const {return Owner == 0 || Nde == Owner->NodeP;}
+
+   // Accessors
+   inline Node *operator ->() {return Nde;}
+   inline Node const *operator ->() const {return Nde;}
+   inline Node const &operator *() const {return *Nde;}
+   inline operator Node *() {return Nde == Owner->NodeP?0:Nde;}
+   inline operator Node const *() const {return Nde == Owner->NodeP?0:Nde;}
+   inline unsigned long Offset() const {return Nde - Owner->NodeP;}
+   inline DirIterator Dir() const {return DirIterator(*Owner,Owner->DirP + Nde->Dir);}
+   inline DiverIterator Diversion() const {return DiverIterator(*Owner,Owner->DiverP + Nde->Pointer);}
+   inline const char *File() const {return Nde->File == 0?0:Owner->StrP + Nde->File;}
+   inline const char *DirN() const {return Owner->StrP + Owner->DirP[Nde->Dir].Name;}
+   Package *RealPackage() const;
+
+   NodeIterator() : Nde(0), Type(NdeHash), Owner(0) {};
+   NodeIterator(pkgFLCache &Owner) : Nde(Owner.NodeP), Type(NdeHash), Owner(&Owner) {}
+   NodeIterator(pkgFLCache &Owner,Node *Trg) : Nde(Trg), Type(NdeHash), Owner(&Owner) {}
+   NodeIterator(pkgFLCache &Owner,Node *Trg,Package *) : Nde(Trg), Type(NdePkg), Owner(&Owner) {}
+};
+
+/* Inlines with forward references that cannot be included directly in their
+   respsective classes */
+inline pkgFLCache::NodeIterator pkgFLCache::DiverIterator::DivertFrom() const
+   {return NodeIterator(*Owner,Owner->NodeP + Diver->DivertFrom);}
+inline pkgFLCache::NodeIterator pkgFLCache::DiverIterator::DivertTo() const
+   {return NodeIterator(*Owner,Owner->NodeP + Diver->DivertTo);}
+
+inline pkgFLCache::NodeIterator pkgFLCache::PkgIterator::Files() const
+   {return NodeIterator(*Owner,Owner->NodeP + Pkg->Files,Pkg);}
+
+inline pkgFLCache::DiverIterator pkgFLCache::DiverBegin()
+   {return DiverIterator(*this,DiverP + HeaderP->Diversions);}
+
+inline pkgFLCache::PkgIterator pkgFLCache::GetPkg(const char *Name,bool Insert)
+   {return GetPkg(Name,Name+strlen(Name),Insert);}
+
+#endif