// -*- mode: cpp; mode: fold -*-
// Description								/*{{{*/
/* ######################################################################

   Writer

   The file writer classes. These write various types of output, sources,
   packages and contents.

   ##################################################################### */
									/*}}}*/
// Include Files							/*{{{*/
#include <config.h>

#include <apt-pkg/configuration.h>
#include <apt-pkg/debfile.h>
#include <apt-pkg/deblistparser.h>
#include <apt-pkg/error.h>
#include <apt-pkg/fileutl.h>
#include <apt-pkg/gpgv.h>
#include <apt-pkg/hashes.h>
#include <apt-pkg/pkgcache.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/tagfile-keys.h>
#include <apt-pkg/tagfile.h>

#include <algorithm>
#include <cctype>
#include <clocale>
#include <cstring>
#include <ctime>
#include <iomanip>
#include <iostream>
#include <memory>
#include <sstream>
#include <utility>
#include <fnmatch.h>
#include <ftw.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include "apt-ftparchive.h"
#include "byhash.h"
#include "cachedb.h"
#include "multicompress.h"
#include "writer.h"

#include <apti18n.h>
									/*}}}*/
using namespace std;
FTWScanner *FTWScanner::Owner;

// ConfigToDoHashes - which hashes to generate				/*{{{*/
static void SingleConfigToDoHashes(unsigned int &DoHashes, std::string const &Conf, unsigned int const Flag)
{
   if (_config->FindB(Conf, (DoHashes & Flag) == Flag) == true)
      DoHashes |= Flag;
   else
      DoHashes &= ~Flag;
}
static void ConfigToDoHashes(unsigned int &DoHashes, std::string const &Conf)
{
   SingleConfigToDoHashes(DoHashes, Conf + "::MD5", Hashes::MD5SUM);
   SingleConfigToDoHashes(DoHashes, Conf + "::SHA1", Hashes::SHA1SUM);
   SingleConfigToDoHashes(DoHashes, Conf + "::SHA256", Hashes::SHA256SUM);
   SingleConfigToDoHashes(DoHashes, Conf + "::SHA512", Hashes::SHA512SUM);
}
									/*}}}*/

// FTWScanner::FTWScanner - Constructor					/*{{{*/
FTWScanner::FTWScanner(FileFd * const GivenOutput, string const &Arch, bool const IncludeArchAll)
   : Arch(Arch), IncludeArchAll(IncludeArchAll), DoHashes(~0)
{
   if (GivenOutput == NULL)
   {
      Output = new FileFd;
      OwnsOutput = true;
      Output->OpenDescriptor(STDOUT_FILENO, FileFd::WriteOnly, false);
   }
   else
   {
      Output = GivenOutput;
      OwnsOutput = false;
   }
   ErrorPrinted = false;
   NoLinkAct = !_config->FindB("APT::FTPArchive::DeLinkAct",true);
   ConfigToDoHashes(DoHashes, "APT::FTPArchive");
}
									/*}}}*/
FTWScanner::~FTWScanner()
{
   if (Output != NULL && OwnsOutput)
      delete Output;
}
// FTWScanner::Scanner - FTW Scanner					/*{{{*/
// ---------------------------------------------------------------------
/* This is the FTW scanner, it processes each directory element in the
   directory tree. */
int FTWScanner::ScannerFTW(const char *File,const struct stat * /*sb*/,int Flag)
{
   if (Flag == FTW_DNR)
   {
      Owner->NewLine(1);
      ioprintf(c1out, _("W: Unable to read directory %s\n"), File);
   }
   if (Flag == FTW_NS)
   {
      Owner->NewLine(1);
      ioprintf(c1out, _("W: Unable to stat %s\n"), File);
   }
   if (Flag != FTW_F)
      return 0;

   return ScannerFile(File, true);
}
									/*}}}*/
static bool FileMatchesPatterns(char const *const File, std::vector<std::string> const &Patterns) /*{{{*/
{
   const char *LastComponent = strrchr(File, '/');
   if (LastComponent == nullptr)
      LastComponent = File;
   else
      ++LastComponent;

   return std::any_of(Patterns.cbegin(), Patterns.cend(), [&](std::string const &pattern) {
      return fnmatch(pattern.c_str(), LastComponent, 0) == 0;
   });
}
									/*}}}*/
int FTWScanner::ScannerFile(const char *const File, bool const ReadLink) /*{{{*/
{
   if (FileMatchesPatterns(File, Owner->Patterns) == false)
      return 0;

   Owner->FilesToProcess.emplace_back(File, ReadLink);
   return 0;
}
									/*}}}*/
int FTWScanner::ProcessFile(const char *const File, bool const ReadLink) /*{{{*/
{
   /* Process it. If the file is a link then resolve it into an absolute
      name.. This works best if the directory components the scanner are
      given are not links themselves. */
   char Jnk[2];
   char *RealPath = NULL;
   Owner->OriginalPath = File;
   if (ReadLink &&
       readlink(File,Jnk,sizeof(Jnk)) != -1 &&
       (RealPath = realpath(File,NULL)) != 0)
   {
      Owner->DoPackage(RealPath);
      free(RealPath);
   }
   else
      Owner->DoPackage(File);

   if (_error->empty() == false)
   {
      // Print any errors or warnings found
      string Err;
      bool SeenPath = false;
      while (_error->empty() == false)
      {
	 Owner->NewLine(1);

	 bool const Type = _error->PopMessage(Err);
	 if (Type == true)
	    cerr << _("E: ") << Err << endl;
	 else
	    cerr << _("W: ") << Err << endl;

	 if (Err.find(File) != string::npos)
	    SeenPath = true;
      }

      if (SeenPath == false)
	 cerr << _("E: Errors apply to file ") << "'" << File << "'" << endl;
      return 0;
   }

   return 0;
}
									/*}}}*/
// FTWScanner::RecursiveScan - Just scan a directory tree		/*{{{*/
// ---------------------------------------------------------------------
/* */
bool FTWScanner::RecursiveScan(string const &Dir)
{
   /* If noprefix is set then jam the scan root in, so we don't generate
      link followed paths out of control */
   if (InternalPrefix.empty() == true)
   {
      char *RealPath = nullptr;
      if ((RealPath = realpath(Dir.c_str(), nullptr)) == 0)
	 return _error->Errno("realpath",_("Failed to resolve %s"),Dir.c_str());
      InternalPrefix = RealPath;
      free(RealPath);
   }

   // Do recursive directory searching
   Owner = this;
   int const Res = ftw(Dir.c_str(),ScannerFTW,30);

   // Error treewalking?
   if (Res != 0)
   {
      if (_error->PendingError() == false)
	 _error->Errno("ftw",_("Tree walking failed"));
      return false;
   }

   using PairType = decltype(*FilesToProcess.cbegin());
   std::sort(FilesToProcess.begin(), FilesToProcess.end(), [](PairType a, PairType b) {
      return a.first < b.first;
   });
   if (not std::all_of(FilesToProcess.cbegin(), FilesToProcess.cend(), [](auto &&it) { return ProcessFile(it.first.c_str(), it.second) == 0; }))
      return false;
   FilesToProcess.clear();
   return true;
}
									/*}}}*/
// FTWScanner::LoadFileList - Load the file list from a file		/*{{{*/
// ---------------------------------------------------------------------
/* This is an alternative to using FTW to locate files, it reads the list
   of files from another file. */
bool FTWScanner::LoadFileList(string const &Dir, string const &File)
{
   /* If noprefix is set then jam the scan root in, so we don't generate
      link followed paths out of control */
   if (InternalPrefix.empty() == true)
   {
      char *RealPath = nullptr;
      if ((RealPath = realpath(Dir.c_str(), nullptr)) == 0)
	 return _error->Errno("realpath",_("Failed to resolve %s"),Dir.c_str());
      InternalPrefix = RealPath;
      free(RealPath);
   }

   Owner = this;
   FILE *List = fopen(File.c_str(),"r");
   if (List == 0)
      return _error->Errno("fopen",_("Failed to open %s"),File.c_str());

   std::string FilePathBuf;
   char *Line = nullptr;
   size_t LineLength = 0;
   while (getline(&Line, &LineLength, List) != -1)
   {
      const char *FileName = _strstrip(Line);
      if (FileName[0] == 0)
	 continue;

      // Relative path, prepend directory to make absolute
      if (FileName[0] != '/')
      {
	 if (Dir.empty() == true || Dir.end()[-1] != '/')
	    strprintf(FilePathBuf, "%s/%s", Dir.c_str(), FileName);
	 else
	    strprintf(FilePathBuf, "%s%s", Dir.c_str(), FileName);

	 FileName = FilePathBuf.c_str();
      }

      if (FileMatchesPatterns(FileName, Patterns) == false)
	 continue;

      if (ProcessFile(FileName, false) != 0)
	 break;
   }

   free(Line);
   fclose(List);
   return true;
}
									/*}}}*/
// FTWScanner::Delink - Delink symlinks					/*{{{*/
// ---------------------------------------------------------------------
/* */
bool FTWScanner::Delink(string &FileName,const char *OriginalPath,
			unsigned long long &DeLinkBytes,
			unsigned long long const &FileSize)
{
   // See if this isn't an internally prefix'd file name.
   if (InternalPrefix.empty() == false &&
       InternalPrefix.length() < FileName.length() &&
       stringcmp(FileName.begin(),FileName.begin() + InternalPrefix.length(),
		 InternalPrefix.begin(),InternalPrefix.end()) != 0)
   {
      if (DeLinkLimit != 0 && DeLinkBytes/1024 < DeLinkLimit)
      {
	 // Tidy up the display
	 if (DeLinkBytes == 0)
	    cout << endl;

	 NewLine(1);
	 ioprintf(c1out, _(" DeLink %s [%s]\n"), (OriginalPath + InternalPrefix.length()),
		    SizeToStr(FileSize).c_str());
	 c1out << flush;

	 if (NoLinkAct == false)
	 {
	    char OldLink[400];
	    if (readlink(OriginalPath,OldLink,sizeof(OldLink)) == -1)
	       _error->Errno("readlink",_("Failed to readlink %s"),OriginalPath);
	    else
	    {
	       if (RemoveFile("FTWScanner::Delink", OriginalPath))
	       {
		  if (link(FileName.c_str(),OriginalPath) != 0)
		  {
		     // Panic! Restore the symlink
		     if (symlink(OldLink,OriginalPath) != 0)
                        _error->Errno("symlink", "failed to restore symlink");
		     return _error->Errno("link",_("*** Failed to link %s to %s"),
					  FileName.c_str(),
					  OriginalPath);
		  }
	       }
	    }
	 }

	 DeLinkBytes += FileSize;
	 if (DeLinkBytes/1024 >= DeLinkLimit)
	    ioprintf(c1out, _(" DeLink limit of %sB hit.\n"), SizeToStr(DeLinkBytes).c_str());
      }

      FileName = OriginalPath;
   }

   return true;
}
									/*}}}*/
// FTWScanner::SetExts - Set extensions to support                      /*{{{*/
// ---------------------------------------------------------------------
/* */
bool FTWScanner::SetExts(string const &Vals)
{
   ClearPatterns();
   string::size_type Start = 0;
   while (Start <= Vals.length()-1)
   {
      string::size_type const Space = Vals.find(' ',Start);
      string::size_type const Length = ((Space == string::npos) ? Vals.length() : Space) - Start;
      if ( Arch.empty() == false )
      {
	 AddPattern(string("*_") + Arch + Vals.substr(Start, Length));
	 if (IncludeArchAll == true && Arch != "all")
	    AddPattern(string("*_all") + Vals.substr(Start, Length));
      }
      else
	 AddPattern(string("*") + Vals.substr(Start, Length));

      Start += Length + 1;
   }

   return true;
}
									/*}}}*/

// PackagesWriter::PackagesWriter - Constructor				/*{{{*/
// ---------------------------------------------------------------------
/* */
PackagesWriter::PackagesWriter(FileFd * const GivenOutput, TranslationWriter * const transWriter,
      string const &DB,string const &Overrides,string const &ExtOverrides,
      string const &Arch, bool const IncludeArchAll) :
   FTWScanner(GivenOutput, Arch, IncludeArchAll), Db(DB), Stats(Db.Stats), TransWriter(transWriter)
{
   SetExts(".deb .ddeb .udeb");
   DeLinkLimit = 0;

   // Process the command line options
   ConfigToDoHashes(DoHashes, "APT::FTPArchive::Packages");
   DoAlwaysStat = _config->FindB("APT::FTPArchive::AlwaysStat", false);
   DoContents = _config->FindB("APT::FTPArchive::Contents",true);
   NoOverride = _config->FindB("APT::FTPArchive::NoOverrideMsg",false);
   LongDescription = _config->FindB("APT::FTPArchive::LongDescription",true);

   if (Db.Loaded() == false)
      DoContents = false;

   // Read the override file
   if (Overrides.empty() == false && Over.ReadOverride(Overrides) == false)
      return;
   else
      NoOverride = true;

   if (ExtOverrides.empty() == false)
      Over.ReadExtraOverride(ExtOverrides);

   _error->DumpErrors();
}
                                                                        /*}}}*/
// PackagesWriter::DoPackage - Process a single package			/*{{{*/
// ---------------------------------------------------------------------
/* This method takes a package and gets its control information and
   MD5, SHA1 and SHA256 then writes out a control record with the proper fields
   rewritten and the path/size/hash appended. */
bool PackagesWriter::DoPackage(string FileName)
{
   // Pull all the data we need form the DB
   if (Db.GetFileInfo(FileName,
	    true, /* DoControl */
	    DoContents,
	    true, /* GenContentsOnly */
	    false, /* DoSource */
	    DoHashes, DoAlwaysStat) == false)
   {
     return false;
   }

   unsigned long long FileSize = Db.GetFileSize();
   if (Delink(FileName,OriginalPath,Stats.DeLinkBytes,FileSize) == false)
      return false;

   // Lookup the override information
   pkgTagSection &Tags = Db.Control.Section;
   auto const Package = Tags.Find(pkgTagSection::Key::Package);
   string_view Architecture;
   // if we generate a Packages file for a given arch, we use it to
   // look for overrides. if we run in "simple" mode without the
   // "Architectures" variable in the config we use the architecture value
   // from the deb file
   if(Arch != "")
      Architecture = Arch;
   else
      Architecture = Tags.Find(pkgTagSection::Key::Architecture);
   unique_ptr<Override::Item> OverItem(Over.GetItem(Package, Architecture));

   if (Package.empty() == true)
      return _error->Error(_("Archive had no package field"));

   // If we need to do any rewriting of the header do it now..
   if (OverItem.get() == 0)
   {
      if (NoOverride == false)
      {
	 NewLine(1);
	 ioprintf(c1out, _("  %.*s has no override entry\n"), (int)Package.size(), Package.data());
      }

      OverItem = unique_ptr<Override::Item>(new Override::Item);
      OverItem->FieldOverride["Section"] = Tags.Find(pkgTagSection::Key::Section);
      OverItem->Priority = Tags.Find(pkgTagSection::Key::Priority);
   }

   // Strip the DirStrip prefix from the FileName and add the PathPrefix
   string NewFileName;
   if (DirStrip.empty() == false &&
       FileName.length() > DirStrip.length() &&
       stringcmp(FileName.begin(),FileName.begin() + DirStrip.length(),
		 DirStrip.begin(),DirStrip.end()) == 0)
      NewFileName = string(FileName.begin() + DirStrip.length(),FileName.end());
   else
      NewFileName = FileName;
   if (PathPrefix.empty() == false)
      NewFileName = flCombine(PathPrefix,NewFileName);

   /* Configuration says we don't want to include the long Description
      in the package file - instead we want to ship a separated file */
   string desc;
   if (LongDescription == false) {
      desc = Tags.Find(pkgTagSection::Key::Description);
      desc += '\n';
      OverItem->FieldOverride["Description"] = desc.substr(0, desc.find('\n'));
   }

   // This lists all the changes to the fields we are going to make.
   std::vector<pkgTagSection::Tag> Changes;
   Changes.push_back(pkgTagSection::Tag::Rewrite("Size", std::to_string(FileSize)));

   for (HashStringList::const_iterator hs = Db.HashesList.begin(); hs != Db.HashesList.end(); ++hs)
   {
      if (hs->HashType() == "MD5Sum")
	 Changes.push_back(pkgTagSection::Tag::Rewrite("MD5sum", hs->HashValue()));
      else if (hs->HashType() == "Checksum-FileSize")
	 continue;
      else
	 Changes.push_back(pkgTagSection::Tag::Rewrite(hs->HashType(), hs->HashValue()));
   }
   Changes.push_back(pkgTagSection::Tag::Rewrite("Filename", NewFileName));
   Changes.push_back(pkgTagSection::Tag::Rewrite("Priority", OverItem->Priority));
   Changes.push_back(pkgTagSection::Tag::Remove("Status"));

   string DescriptionMd5;
   if (LongDescription == false) {
      Hashes descmd5(Hashes::MD5SUM);
      descmd5.Add(desc.c_str());
      DescriptionMd5 = descmd5.GetHashString(Hashes::MD5SUM).HashValue();
      Changes.push_back(pkgTagSection::Tag::Rewrite("Description-md5", DescriptionMd5));
      if (TransWriter != NULL)
	 TransWriter->DoPackage(Package, desc, DescriptionMd5);
   }

   // Rewrite the maintainer field if necessary
   bool MaintFailed;
   string NewMaint = OverItem->SwapMaint(Tags.Find(pkgTagSection::Key::Maintainer), MaintFailed);
   if (MaintFailed == true)
   {
      if (NoOverride == false)
      {
	 const auto Maint = Tags.Find(pkgTagSection::Key::Maintainer);
         NewLine(1);
	 ioprintf(c1out, _("  %.*s maintainer is %.*s not %s\n"),
	       (int)Package.size(), Package.data(), (int)Maint.size(), Maint.data(), OverItem->OldMaint.c_str());
      }
   }

   if (NewMaint.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Maintainer", NewMaint));

   for (map<string,string>::const_iterator I = OverItem->FieldOverride.begin();
        I != OverItem->FieldOverride.end(); ++I)
      Changes.push_back(pkgTagSection::Tag::Rewrite(I->first, I->second));

   // Rewrite and store the fields.
   if (Tags.Write(*Output, TFRewritePackageOrder, Changes) == false ||
	 Output->Write("\n", 1) == false)
      return false;

   return Db.Finish();
}
									/*}}}*/
PackagesWriter::~PackagesWriter()					/*{{{*/
{
}
									/*}}}*/

// TranslationWriter::TranslationWriter - Constructor			/*{{{*/
// ---------------------------------------------------------------------
/* Create a Translation-Master file for this Packages file */
TranslationWriter::TranslationWriter(string const &File, string const &TransCompress,
					mode_t const &Permissions) : Comp(NULL), Output(NULL)
{
   if (File.empty() == true)
      return;

   Comp = new MultiCompress(File, TransCompress, Permissions);
   Output = &Comp->Input;
}
									/*}}}*/
// TranslationWriter::DoPackage - Process a single package		/*{{{*/
// ---------------------------------------------------------------------
/* Create a Translation-Master file for this Packages file */
bool TranslationWriter::DoPackage(string_view Pkg, string const &Desc,
				  string const &MD5)
{
   if (Output == NULL)
      return true;

   // Different archs can include different versions and therefore
   // different descriptions - so we need to check for both name and md5.
   string const Record = string{Pkg} + ":" + MD5;

   if (Included.find(Record) != Included.end())
      return true;

   std::string out;
   strprintf(out, "Package: %.*s\nDescription-md5: %s\nDescription-en: %s\n",
	   (int)Pkg.size(), Pkg.data(), MD5.c_str(), Desc.c_str());
   Output->Write(out.c_str(), out.length());

   Included.insert(Record);
   return true;
}
									/*}}}*/
// TranslationWriter::~TranslationWriter - Destructor			/*{{{*/
// ---------------------------------------------------------------------
/* */
TranslationWriter::~TranslationWriter()
{
   if (Comp != NULL)
      delete Comp;
}
									/*}}}*/

// SourcesWriter::SourcesWriter - Constructor				/*{{{*/
// ---------------------------------------------------------------------
/* */
SourcesWriter::SourcesWriter(FileFd * const GivenOutput, string const &DB, string const &BOverrides,string const &SOverrides,
			     string const &ExtOverrides) :
   FTWScanner(GivenOutput), Db(DB), Stats(Db.Stats)
{
   AddPattern("*.dsc");
   DeLinkLimit = 0;
   Buffer = 0;
   BufSize = 0;

   // Process the command line options
   ConfigToDoHashes(DoHashes, "APT::FTPArchive::Sources");
   NoOverride = _config->FindB("APT::FTPArchive::NoOverrideMsg",false);
   DoAlwaysStat = _config->FindB("APT::FTPArchive::AlwaysStat", false);

   // Read the override file
   if (BOverrides.empty() == false && BOver.ReadOverride(BOverrides) == false)
      return;
   else
      NoOverride = true;

   // WTF?? The logic above: if we can't read binary overrides, don't even try
   // reading source overrides. if we can read binary overrides, then say there
   // are no overrides. THIS MAKES NO SENSE! -- ajt@d.o, 2006/02/28

   if (ExtOverrides.empty() == false)
      SOver.ReadExtraOverride(ExtOverrides);

   if (SOverrides.empty() == false && FileExists(SOverrides) == true)
      SOver.ReadOverride(SOverrides,true);
}
									/*}}}*/
// SourcesWriter::DoPackage - Process a single package			/*{{{*/
static std::string getDscHash(unsigned int const DoHashes,
      Hashes::SupportedHashes const DoIt, pkgTagSection &Tags, pkgTagSection::Key const FieldKey,
      HashString const * const Hash, unsigned long long Size, std::string_view const &FileName)
{
   if ((DoHashes & DoIt) != DoIt || not Tags.Exists(FieldKey) || Hash == nullptr)
      return "";
   std::ostringstream out;
   out << "\n " << Hash->HashValue() << " " << std::to_string(Size) << " " << FileName
      << "\n " << Tags.Find(FieldKey);
   return out.str();
}
bool SourcesWriter::DoPackage(string FileName)
{
   // Pull all the data we need form the DB
   if (Db.GetFileInfo(FileName,
	    false, /* DoControl */
	    false, /* DoContents */
	    false, /* GenContentsOnly */
	    true, /* DoSource */
	    DoHashes, DoAlwaysStat) == false)
   {
      return false;
   }

   // we need to perform a "write" here (this is what finish is doing)
   // because the call to Db.GetFileInfo() in the loop will change
   // the "db cursor"
   Db.Finish();

   pkgTagSection Tags;
   if (Tags.Scan(Db.Dsc.Data.c_str(), Db.Dsc.Data.length()) == false)
      return _error->Error("Could not find a record in the DSC '%s'",FileName.c_str());

   if (not Tags.Exists(pkgTagSection::Key::Source))
      return _error->Error("Could not find a Source entry in the DSC '%s'",FileName.c_str());
   Tags.Trim();

   // Lookup the override information, finding first the best priority.
   string BestPrio;
   auto const Bins = Tags.Find(pkgTagSection::Key::Binary);
   char Buffer[Bins.length() + 1];
   unique_ptr<Override::Item> OverItem(nullptr);
   if (Bins.empty() == false)
   {
      strncpy(Buffer, Bins.data(), Bins.length());
      Buffer[Bins.length()] = '\0';

      // Ignore too-long errors.
      char *BinList[400];
      TokSplitString(',',Buffer,BinList,sizeof(BinList)/sizeof(BinList[0]));

      // Look at all the binaries
      unsigned char BestPrioV = pkgCache::State::Extra;
      for (unsigned I = 0; BinList[I] != 0; I++)
      {
	 unique_ptr<Override::Item> Itm(BOver.GetItem(BinList[I]));
	 if (Itm.get() == 0)
	    continue;

	 unsigned char NewPrioV = debListParser::GetPrio(Itm->Priority);
	 if (NewPrioV < BestPrioV || BestPrio.empty() == true)
	 {
	    BestPrioV = NewPrioV;
	    BestPrio = Itm->Priority;
	 }

	 if (OverItem.get() == 0)
	    OverItem = std::move(Itm);
      }
   }

   // If we need to do any rewriting of the header do it now..
   if (OverItem.get() == 0)
   {
      if (NoOverride == false)
      {
         const auto Source = Tags.Find(pkgTagSection::Key::Source);
	 NewLine(1);
	 ioprintf(c1out, _("  %.*s has no override entry\n"), (int)Source.size(), Source.data());
      }

      OverItem.reset(new Override::Item);
   }

   struct stat St;
   if (stat(FileName.c_str(), &St) != 0)
      return _error->Errno("fstat","Failed to stat %s",FileName.c_str());

   auto const Package = Tags.Find(pkgTagSection::Key::Source);
   unique_ptr<Override::Item> SOverItem(SOver.GetItem(Package));
   // const unique_ptr<Override::Item> autoSOverItem(SOverItem);
   if (SOverItem.get() == 0)
   {
      ioprintf(c1out, _("  %.*s has no source override entry\n"), (int)Package.size(), Package.data());
      SOverItem = unique_ptr<Override::Item>(BOver.GetItem(Package));
      if (SOverItem.get() == 0)
      {
        ioprintf(c1out, _("  %.*s has no binary override entry either\n"), (int)Package.size(), Package.data());
	 SOverItem = unique_ptr<Override::Item>(new Override::Item);
	 *SOverItem = *OverItem;
      }
   }

   // Add the dsc to the files hash list
   auto const strippedName = flNotDir(FileName);
   std::string const Files = getDscHash(DoHashes, Hashes::MD5SUM, Tags, pkgTagSection::Key::Files, Db.HashesList.find("MD5Sum"), St.st_size, strippedName);
   std::string ChecksumsSha1 = getDscHash(DoHashes, Hashes::SHA1SUM, Tags, pkgTagSection::Key::Checksums_Sha1, Db.HashesList.find("SHA1"), St.st_size, strippedName);
   std::string ChecksumsSha256 = getDscHash(DoHashes, Hashes::SHA256SUM, Tags, pkgTagSection::Key::Checksums_Sha256, Db.HashesList.find("SHA256"), St.st_size, strippedName);
   std::string ChecksumsSha512 = getDscHash(DoHashes, Hashes::SHA512SUM, Tags, pkgTagSection::Key::Checksums_Sha512, Db.HashesList.find("SHA512"), St.st_size, strippedName);

   // Strip the DirStrip prefix from the FileName and add the PathPrefix
   string NewFileName;
   if (DirStrip.empty() == false &&
       FileName.length() > DirStrip.length() &&
       stringcmp(DirStrip,OriginalPath,OriginalPath + DirStrip.length()) == 0)
      NewFileName = string(OriginalPath + DirStrip.length());
   else
      NewFileName = OriginalPath;
   if (PathPrefix.empty() == false)
      NewFileName = flCombine(PathPrefix,NewFileName);

   string Directory = flNotFile(OriginalPath);

   // Perform operation over all of the files
   string ParseJnk;
   const char *C = Files.c_str();
   char *RealPath = NULL;
   for (;isspace(*C); C++);
   while (*C != 0)
   {
      // Parse each of the elements
      if (ParseQuoteWord(C,ParseJnk) == false ||
	  ParseQuoteWord(C,ParseJnk) == false ||
	  ParseQuoteWord(C,ParseJnk) == false)
	 return _error->Error("Error parsing file record");

      string OriginalPath = Directory + ParseJnk;

      // Add missing hashes to source files
      if (((DoHashes & Hashes::SHA1SUM) == Hashes::SHA1SUM && not Tags.Exists(pkgTagSection::Key::Checksums_Sha1)) ||
          ((DoHashes & Hashes::SHA256SUM) == Hashes::SHA256SUM && not Tags.Exists(pkgTagSection::Key::Checksums_Sha256)) ||
          ((DoHashes & Hashes::SHA512SUM) == Hashes::SHA512SUM && not Tags.Exists(pkgTagSection::Key::Checksums_Sha512)))
      {
         if (Db.GetFileInfo(OriginalPath,
                            false, /* DoControl */
                            false, /* DoContents */
                            false, /* GenContentsOnly */
                            false, /* DoSource */
                            DoHashes,
                            DoAlwaysStat) == false)
         {
            return _error->Error("Error getting file info");
         }

         for (HashStringList::const_iterator hs = Db.HashesList.begin(); hs != Db.HashesList.end(); ++hs)
	 {
	    if (hs->HashType() == "MD5Sum" || hs->HashType() == "Checksum-FileSize")
	       continue;
	    pkgTagSection::Key fieldkey;
	    std::string * out;
	    if (hs->HashType() == "SHA1")
	    {
	       fieldkey = pkgTagSection::Key::Checksums_Sha1;
	       out = &ChecksumsSha1;
	    }
	    else if (hs->HashType() == "SHA256")
	    {
	       fieldkey = pkgTagSection::Key::Checksums_Sha256;
	       out = &ChecksumsSha256;
	    }
	    else if (hs->HashType() == "SHA512")
	    {
	       fieldkey = pkgTagSection::Key::Checksums_Sha512;
	       out = &ChecksumsSha512;
	    }
	    else
	    {
	       _error->Warning("Ignoring unknown Checksumtype %s in SourcesWriter::DoPackages", hs->HashType().c_str());
	       continue;
	    }
	    if (Tags.Exists(fieldkey))
	       continue;
	    std::ostringstream streamout;
	    streamout << "\n " << hs->HashValue() << " " << std::to_string(Db.GetFileSize()) << " " << ParseJnk;
	    out->append(streamout.str());
	 }

	 // write back the GetFileInfo() stats data
	 Db.Finish();
      }

      // Perform the delinking operation
      char Jnk[2];

      if (readlink(OriginalPath.c_str(),Jnk,sizeof(Jnk)) != -1 &&
	  (RealPath = realpath(OriginalPath.c_str(),NULL)) != 0)
      {
	 string RP = RealPath;
	 free(RealPath);
	 if (Delink(RP,OriginalPath.c_str(),Stats.DeLinkBytes,St.st_size) == false)
	    return false;
      }
   }

   Directory = flNotFile(NewFileName);
   if (Directory.length() > 2)
      Directory.erase(Directory.end()-1);

   // This lists all the changes to the fields we are going to make.
   // (5 hardcoded + checksums + maintainer + end marker)
   std::vector<pkgTagSection::Tag> Changes;

   Changes.push_back(pkgTagSection::Tag::Remove("Source"));
   Changes.push_back(pkgTagSection::Tag::Rewrite("Package", Package));
   if (Files.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Files", Files));
   else
      Changes.push_back(pkgTagSection::Tag::Remove("Files"));
   if (ChecksumsSha1.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Checksums-Sha1", ChecksumsSha1));
   else
      Changes.push_back(pkgTagSection::Tag::Remove("Checksums-Sha1"));
   if (ChecksumsSha256.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Checksums-Sha256", ChecksumsSha256));
   else
      Changes.push_back(pkgTagSection::Tag::Remove("Checksums-Sha256"));
   if (ChecksumsSha512.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Checksums-Sha512", ChecksumsSha512));
   else
      Changes.push_back(pkgTagSection::Tag::Remove("Checksums-Sha512"));
   if (Directory != "./")
      Changes.push_back(pkgTagSection::Tag::Rewrite("Directory", Directory));
   Changes.push_back(pkgTagSection::Tag::Rewrite("Priority", BestPrio));
   Changes.push_back(pkgTagSection::Tag::Remove("Status"));

   // Rewrite the maintainer field if necessary
   bool MaintFailed;
   string NewMaint = OverItem->SwapMaint(Tags.Find(pkgTagSection::Key::Maintainer), MaintFailed);
   if (MaintFailed == true)
   {
      if (NoOverride == false)
      {
	 const auto Maint = Tags.Find(pkgTagSection::Key::Maintainer);
         NewLine(1);
	 ioprintf(c1out, _("  %.*s maintainer is %.*s not %s\n"), (int)Package.size(), Package.data(),
	       (int)Maint.size(), Maint.data(), OverItem->OldMaint.c_str());
      }
   }
   if (NewMaint.empty() == false)
      Changes.push_back(pkgTagSection::Tag::Rewrite("Maintainer", NewMaint.c_str()));

   for (map<string,string>::const_iterator I = SOverItem->FieldOverride.begin();
        I != SOverItem->FieldOverride.end(); ++I)
      Changes.push_back(pkgTagSection::Tag::Rewrite(I->first, I->second));

   // Rewrite and store the fields.
   if (Tags.Write(*Output, TFRewriteSourceOrder, Changes) == false ||
	 Output->Write("\n", 1) == false)
      return false;

   Stats.Packages++;

   return true;
}
									/*}}}*/

// ContentsWriter::ContentsWriter - Constructor				/*{{{*/
// ---------------------------------------------------------------------
/* */
ContentsWriter::ContentsWriter(FileFd * const GivenOutput, string const &DB,
      string const &Arch, bool const IncludeArchAll) :
		    FTWScanner(GivenOutput, Arch, IncludeArchAll), Db(DB), Stats(Db.Stats)

{
   SetExts(".deb");
}
									/*}}}*/
// ContentsWriter::DoPackage - Process a single package			/*{{{*/
// ---------------------------------------------------------------------
/* If Package is the empty string the control record will be parsed to
   determine what the package name is. */
bool ContentsWriter::DoPackage(string FileName, string Package)
{
   if (!Db.GetFileInfo(FileName,
	    Package.empty(), /* DoControl */
	    true, /* DoContents */
	    false, /* GenContentsOnly */
	    false, /* DoSource */
	    0, /* DoHashes */
	    false /* checkMtime */))
   {
      return false;
   }

   // Parse the package name
   if (Package.empty() == true)
   {
      Package = Db.Control.Section.Find(pkgTagSection::Key::Package);
   }

   Db.Contents.Add(Gen,std::move(Package));

   return Db.Finish();
}
									/*}}}*/
// ContentsWriter::ReadFromPkgs - Read from a packages file		/*{{{*/
// ---------------------------------------------------------------------
/* */
bool ContentsWriter::ReadFromPkgs(string const &PkgFile,string const &PkgCompress)
{
   MultiCompress Pkgs(PkgFile,PkgCompress,0,false);
   if (_error->PendingError() == true)
      return false;

   // Open the package file
   FileFd Fd;
   if (Pkgs.OpenOld(Fd) == false)
      return false;

   pkgTagFile Tags(&Fd);
   if (_error->PendingError() == true)
      return false;

   // Parse.
   pkgTagSection Section;
   while (Tags.Step(Section) == true)
   {
      auto File = flCombine(Prefix, string{Section.Find(pkgTagSection::Key::Filename)});
      auto Package = flCombine(string{Section.Find(pkgTagSection::Key::Section)}, string{Section.Find(pkgTagSection::Key::Package)});
      DoPackage(std::move(File), std::move(Package));
      if (_error->empty() == false)
      {
	 _error->Error("Errors apply to file '%s'",File.c_str());
	 _error->DumpErrors();
      }
   }

   // Tidy the compressor
   Fd.Close();

   return true;
}

									/*}}}*/

// ReleaseWriter::ReleaseWriter - Constructor				/*{{{*/
// ---------------------------------------------------------------------
/* */
static std::string formatUTCDateTime(time_t const now)
{
   bool const NumericTimezone = _config->FindB("APT::FTPArchive::Release::NumericTimezone", true);
   // TimeRFC1123 uses GMT to satisfy HTTP/1.1
   std::string datetime = TimeRFC1123(now, NumericTimezone);
   if (NumericTimezone == false)
   {
      auto const lastspace = datetime.rfind(' ');
      if (likely(lastspace != std::string::npos))
	 datetime.replace(lastspace + 1, 3, "UTC");
   }
   return datetime;
}
ReleaseWriter::ReleaseWriter(FileFd * const GivenOutput, string const &/*DB*/) : FTWScanner(GivenOutput)
{
   if (_config->FindB("APT::FTPArchive::Release::Default-Patterns", true) == true)
   {
      AddPattern("Packages");
      AddPattern("Packages.*");
      AddPattern("Translation-*");
      AddPattern("Sources");
      AddPattern("Sources.*");
      AddPattern("Release");
      AddPattern("Contents-*");
      AddPattern("Index");
      AddPattern("Index.*");
      AddPattern("icons-*.tar");
      AddPattern("icons-*.tar.*");
      AddPattern("Components-*.yml");
      AddPattern("Components-*.yml.*");
      AddPattern("md5sum.txt");
   }
   AddPatterns(_config->FindVector("APT::FTPArchive::Release::Patterns"));

   time_t const now = time(NULL);
   time_t const validuntil = now + _config->FindI("APT::FTPArchive::Release::ValidTime", 0);

   map<string,bool> BoolFields;
   map<string,string> Fields;
   Fields["Origin"] = "";
   Fields["Label"] = "";
   Fields["Suite"] = "";
   Fields["Version"] = "";
   Fields["Codename"] = "";
   Fields["Date"] = formatUTCDateTime(now);
   if (validuntil != now)
      Fields["Valid-Until"] = formatUTCDateTime(validuntil);
   Fields["Architectures"] = "";
   Fields["Components"] = "";
   Fields["Description"] = "";
   Fields["Signed-By"] = "";
   BoolFields["Acquire-By-Hash"] = _config->FindB("APT::FTPArchive::DoByHash", false);
   BoolFields["NotAutomatic"] = false;
   BoolFields["ButAutomaticUpgrades"] = false;

   // Read configuration for string fields, but don't output them
   for (auto &&I : Fields)
   {
      string Config = string("APT::FTPArchive::Release::") + I.first;
      I.second = _config->Find(Config, I.second);
   }

   // Read configuration for bool fields, and add them to Fields if true
   for (auto &&I : BoolFields)
   {
      string Config = string("APT::FTPArchive::Release::") + I.first;
      I.second = _config->FindB(Config, I.second);
      if (I.second)
         Fields[I.first] = "yes";
   }

   // All configuration read and stored in Fields; output
   for (auto &&I : Fields)
   {
      if (I.second.empty())
         continue;
      std::string const out = I.first + ": " + I.second + "\n";
      Output->Write(out.c_str(), out.length());
   }

   ConfigToDoHashes(DoHashes, "APT::FTPArchive::Release");
}
									/*}}}*/
// ReleaseWriter::DoPackage - Process a single package			/*{{{*/
// ---------------------------------------------------------------------
bool ReleaseWriter::DoPackage(string FileName)
{
   // Strip the DirStrip prefix from the FileName and add the PathPrefix
   string NewFileName;
   if (DirStrip.empty() == false &&
       FileName.length() > DirStrip.length() &&
       stringcmp(FileName.begin(),FileName.begin() + DirStrip.length(),
		 DirStrip.begin(),DirStrip.end()) == 0)
   {
      NewFileName = string(FileName.begin() + DirStrip.length(),FileName.end());
      while (NewFileName[0] == '/')
         NewFileName = string(NewFileName.begin() + 1,NewFileName.end());
   }
   else
      NewFileName = FileName;

   if (PathPrefix.empty() == false)
      NewFileName = flCombine(PathPrefix,NewFileName);

   FileFd fd(FileName, FileFd::ReadOnly);

   if (!fd.IsOpen())
   {
      return false;
   }

   CheckSums[NewFileName].size = fd.Size();

   Hashes hs(DoHashes);
   hs.AddFD(fd);
   CheckSums[NewFileName].Hashes = hs.GetHashStringList();
   fd.Close();

   // FIXME: wrong layer in the code(?)
   // FIXME2: symlink instead of create a copy
   if (_config->FindB("APT::FTPArchive::DoByHash", false) == true)
   {
      std::string Input = FileName;
      HashStringList hsl = hs.GetHashStringList();
      for(HashStringList::const_iterator h = hsl.begin();
          h != hsl.end(); ++h)
      {
         if (!h->usable())
            continue;
         if (flNotDir(FileName) == "Release" || flNotDir(FileName) == "InRelease")
            continue;

         std::string ByHashOutputFile = GenByHashFilename(Input, *h);
         std::string ByHashOutputDir = flNotFile(ByHashOutputFile);
         if(!CreateDirectory(flNotFile(Input), ByHashOutputDir))
            return _error->Warning("can not create dir %s", flNotFile(ByHashOutputFile).c_str());

         // write new hashes
         FileFd In(Input, FileFd::ReadOnly);
         FileFd Out(ByHashOutputFile, FileFd::WriteEmpty);
         if(!CopyFile(In, Out))
            return _error->Warning("failed to copy %s %s", Input.c_str(), ByHashOutputFile.c_str());
      }
   }

   return true;
}

									/*}}}*/
// ReleaseWriter::Finish - Output the checksums				/*{{{*/
// ---------------------------------------------------------------------
static void printChecksumTypeRecord(FileFd &Output, char const * const Type, map<string, ReleaseWriter::CheckSum> const &CheckSums)
{
   {
      std::string out;
      strprintf(out, "%s:\n", Type);
      Output.Write(out.c_str(), out.length());
   }
   for(map<string,ReleaseWriter::CheckSum>::const_iterator I = CheckSums.begin();
	 I != CheckSums.end(); ++I)
   {
      HashString const * const hs = I->second.Hashes.find(Type);
      if (hs == NULL)
	 continue;
      std::string out;
      strprintf(out, " %s %16llu %s\n",
	    hs->HashValue().c_str(),
	    (*I).second.size,
	    (*I).first.c_str());
      Output.Write(out.c_str(), out.length());
   }
}
void ReleaseWriter::Finish()
{
   if ((DoHashes & Hashes::MD5SUM) == Hashes::MD5SUM)
      printChecksumTypeRecord(*Output, "MD5Sum", CheckSums);
   if ((DoHashes & Hashes::SHA1SUM) == Hashes::SHA1SUM)
      printChecksumTypeRecord(*Output, "SHA1", CheckSums);
   if ((DoHashes & Hashes::SHA256SUM) == Hashes::SHA256SUM)
      printChecksumTypeRecord(*Output, "SHA256", CheckSums);
   if ((DoHashes & Hashes::SHA512SUM) == Hashes::SHA512SUM)
      printChecksumTypeRecord(*Output, "SHA512", CheckSums);

   // go by-hash cleanup
   map<string,ReleaseWriter::CheckSum>::const_iterator prev = CheckSums.begin();
   if (_config->FindB("APT::FTPArchive::DoByHash", false) == true)
   {
      for(map<string,ReleaseWriter::CheckSum>::const_iterator I = CheckSums.begin();
	 I != CheckSums.end(); ++I)
      {
         if (I->first == "Release" || I->first == "InRelease")
            continue;

         // keep iterating until we find a new subdir
         if(flNotFile(I->first) == flNotFile(prev->first))
            continue;

         // clean that subdir up
         int keepFiles = _config->FindI("APT::FTPArchive::By-Hash-Keep", 3);
         // calculate how many compressors are used (the amount of files
         // in that subdir generated for this run)
         keepFiles *= std::distance(prev, I);
         prev = I;

         HashStringList hsl = prev->second.Hashes;
         for(HashStringList::const_iterator h = hsl.begin();
             h != hsl.end(); ++h)
         {

            if (!h->usable())
               continue;

            std::string RealFilename = DirStrip+"/"+prev->first;
            std::string ByHashOutputFile = GenByHashFilename(RealFilename, *h);
            DeleteAllButMostRecent(flNotFile(ByHashOutputFile), keepFiles);
         }
      }
   }
}