// -*- mode: cpp; mode: fold -*-
// Description                                                          /*{{{*/
// $Id: indexcopy.cc,v 1.2 2002/07/25 18:07:18 niemeyer Exp $
/* ######################################################################

   Index Copying - Aid for copying and verifying the index files
   
   This class helps apt-cache reconstruct a damaged index files. 
   
   ##################################################################### */
                                                                        /*}}} */
// Include Files                                                        /*{{{*/
#include "indexcopy.h"
#include "i18n.h"

#include <apt-pkg/error.h>
#include <apt-pkg/progress.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/fileutl.h>
#include <apt-pkg/configuration.h>
#include <apt-pkg/tagfile.h>

#include <iostream>
#include <unistd.h>
#include <sys/stat.h>
#include <stdio.h>
                                                                        /*}}} */

using namespace std;

// IndexCopy::CopyPackages - Copy the package files from the CD         /*{{{*/
// ---------------------------------------------------------------------
/* */
bool IndexCopy::CopyPackages(string CDROM, string Name,
                             vector<string> &List)
{
   if (List.size() == 0)
      return true;

   OpTextProgress Progress;

   bool NoStat = _config->FindB("APT::CDROM::Fast", false);
   bool Debug = _config->FindB("Debug::aptcdrom", false);

   // Prepare the progress indicator
   unsigned long TotalSize = 0;
   for (vector<string>::iterator I = List.begin(); I != List.end(); I++) {
      struct stat Buf;
      if (stat(string(*I + GetFileName()).c_str(), &Buf) != 0 &&
          stat(string(*I + GetFileName() + ".gz").c_str(), &Buf) != 0)
         return _error->Errno("stat", _("Stat failed for %s"),
                              string(*I + GetFileName()).c_str());
      TotalSize += Buf.st_size;
   }

   unsigned long CurrentSize = 0;
   unsigned int NotFound = 0;
   unsigned int WrongSize = 0;
   unsigned int Packages = 0;
   for (vector<string>::iterator I = List.begin(); I != List.end(); I++) {
      string OrigPath = string(*I, CDROM.length());
      unsigned long FileSize = 0;

      // Open the package file
      FileFd Pkg;
      if (FileExists(*I + GetFileName()) == true) {
         Pkg.Open(*I + GetFileName(), FileFd::ReadOnly);
         FileSize = Pkg.Size();
      } else {
         FileFd From(*I + GetFileName() + ".gz", FileFd::ReadOnly);
         if (_error->PendingError() == true)
            return false;
         FileSize = From.Size();

         // Get a temp file
         FILE *tmp = tmpfile();
         if (tmp == 0)
            return _error->Errno("tmpfile", _("Unable to create a tmp file"));
         Pkg.Fd(dup(fileno(tmp)));
         fclose(tmp);

         // Fork gzip
         int Process = fork();
         if (Process < 0)
            return _error->Errno("fork",
                                 "Internal Error: Couldn't fork gzip. Please report.");

         // The child
         if (Process == 0) {
            dup2(From.Fd(), STDIN_FILENO);
            dup2(Pkg.Fd(), STDOUT_FILENO);
            SetCloseExec(STDIN_FILENO, false);
            SetCloseExec(STDOUT_FILENO, false);

            const char *Args[3];
            string Tmp = _config->Find("Dir::bin::gzip", "gzip");
            Args[0] = Tmp.c_str();
            Args[1] = "-d";
            Args[2] = 0;
            execvp(Args[0], (char **)Args);
            exit(100);
         }
         // Wait for gzip to finish
         if (ExecWait
             (Process, _config->Find("Dir::bin::gzip", "gzip").c_str(),
              false) == false)
            return _error->Error(_("gzip failed, perhaps the disk is full."));

         Pkg.Seek(0);
      }
      pkgTagFile Parser(&Pkg);
      if (_error->PendingError() == true)
         return false;

      // Open the output file
      char S[400];
      snprintf(S, sizeof(S), "cdrom:[%s]/%s%s", Name.c_str(),
               (*I).c_str() + CDROM.length(), GetFileName());
      string TargetF = _config->FindDir("Dir::State::lists") + "partial/";
      TargetF += URItoFileName(S);
      if (_config->FindB("APT::CDROM::NoAct", false) == true)
         TargetF = "/dev/null";
      FileFd Target(TargetF, FileFd::WriteEmpty);
      FILE *TargetFl = fdopen(dup(Target.Fd()), "w");
      if (_error->PendingError() == true)
         return false;
      if (TargetFl == 0)
         return _error->Errno("fdopen", _("Failed to reopen fd"));

      // Setup the progress meter
      Progress.OverallProgress(CurrentSize, TotalSize, FileSize,
                               string("Reading ") + Type() + " Indexes");

      // Parse
      Progress.SubProgress(Pkg.Size());
      pkgTagSection Section;
      this->Section = &Section;
      string Prefix;
      unsigned long Hits = 0;
      unsigned long Chop = 0;
      while (Parser.Step(Section) == true) {
         Progress.Progress(Parser.Offset());
         string File;
         unsigned long Size;
         if (GetFile(File, Size) == false) {
            fclose(TargetFl);
            return false;
         }

         if (Chop != 0)
            File = OrigPath + ChopDirs(File, Chop);

         // See if the file exists
         bool Mangled = false;
         if (NoStat == false || Hits < 10) {
            // Attempt to fix broken structure
            if (Hits == 0) {
               if (ReconstructPrefix(Prefix, OrigPath, CDROM, File) == false &&
                   ReconstructChop(Chop, *I, File) == false) {
                  if (Debug == true)
                     clog << "Missed: " << File << endl;
                  NotFound++;
                  continue;
               }
               if (Chop != 0)
                  File = OrigPath + ChopDirs(File, Chop);
            }
            // Get the size
            struct stat Buf;
            if (stat(string(CDROM + Prefix + File).c_str(), &Buf) != 0 ||
                Buf.st_size == 0) {
               // Attempt to fix busted symlink support for one instance
               string OrigFile = File;
               string::size_type Start = File.find("binary-");
               string::size_type End = File.find("/", Start + 3);
               if (Start != string::npos && End != string::npos) {
                  File.replace(Start, End - Start, "binary-all");
                  Mangled = true;
               }

               if (Mangled == false ||
                   stat(string(CDROM + Prefix + File).c_str(), &Buf) != 0) {
                  if (Debug == true)
                     clog << "Missed(2): " << OrigFile << endl;
                  NotFound++;
                  continue;
               }
            }
            // Size match
            if ((unsigned)Buf.st_size != Size) {
               if (Debug == true)
                  clog << "Wrong Size: " << File << endl;
               WrongSize++;
               continue;
            }
         }

         Packages++;
         Hits++;

         if (RewriteEntry(TargetFl, File) == false) {
            fclose(TargetFl);
            return false;
         }
      }
      fclose(TargetFl);

      if (Debug == true)
         cout << " Processed by using Prefix '" << Prefix <<
            "' and chop " << Chop << endl;

      if (_config->FindB("APT::CDROM::NoAct", false) == false) {
         // Move out of the partial directory
         Target.Close();
         string FinalF = _config->FindDir("Dir::State::lists");
         FinalF += URItoFileName(S);
         if (rename(TargetF.c_str(), FinalF.c_str()) != 0)
            return _error->Errno("rename", _("Failed to rename"));

         // Copy the release file
         snprintf(S, sizeof(S), "cdrom:[%s]/%sRelease", Name.c_str(),
                  (*I).c_str() + CDROM.length());
         string TargetF = _config->FindDir("Dir::State::lists") + "partial/";
         TargetF += URItoFileName(S);
         if (FileExists(*I + "Release") == true) {
            FileFd Target(TargetF, FileFd::WriteEmpty);
            FileFd Rel(*I + "Release", FileFd::ReadOnly);
            if (_error->PendingError() == true)
               return false;

            if (CopyFile(Rel, Target) == false)
               return false;
         } else {
            // Empty release file
            FileFd Target(TargetF, FileFd::WriteEmpty);
         }

         // Rename the release file
         FinalF = _config->FindDir("Dir::State::lists");
         FinalF += URItoFileName(S);
         if (rename(TargetF.c_str(), FinalF.c_str()) != 0)
            return _error->Errno("rename", _("Failed to rename"));
      }

      /* Mangle the source to be in the proper notation with
         prefix dist [component] */
      *I = string(*I, Prefix.length());
      ConvertToSourceList(CDROM, *I);
      *I = Prefix + ' ' + *I;

      CurrentSize += FileSize;
   }
   Progress.Done();

   // Some stats
   cout << "Wrote " << Packages << " records";
   if (NotFound != 0)
      cout << " with " << NotFound << " missing files";
   if (NotFound != 0 && WrongSize != 0)
      cout << " and";
   if (WrongSize != 0)
      cout << " with " << WrongSize << " mismatched files";
   cout << '.' << endl;

   if (Packages == 0)
      _error->Warning(_("No valid records were found."));

   if (NotFound + WrongSize > 10)
      cout << "Alot of entries were discarded, something may be wrong." <<
         endl;

   return true;
}

                                                                        /*}}} */
// IndexCopy::ChopDirs - Chop off the leading directory components      /*{{{*/
// ---------------------------------------------------------------------
/* */
string IndexCopy::ChopDirs(string Path, unsigned int Depth)
{
   string::size_type I = 0;
   do {
      I = Path.find('/', I + 1);
      Depth--;
   }
   while (I != string::npos && Depth != 0);

   if (I == string::npos)
      return string();

   return string(Path, I + 1);
}

                                                                        /*}}} */
// IndexCopy::ReconstructPrefix - Fix strange prefixing                 /*{{{*/
// ---------------------------------------------------------------------
/* This prepends dir components from the path to the package files to
   the path to the deb until it is found */
bool IndexCopy::ReconstructPrefix(string &Prefix, string OrigPath, string CD,
                                  string File)
{
   bool Debug = _config->FindB("Debug::aptcdrom", false);
   unsigned int Depth = 1;
   string MyPrefix = Prefix;
   while (1) {
      struct stat Buf;
      if (stat(string(CD + MyPrefix + File).c_str(), &Buf) != 0) {
         if (Debug == true)
            cout << "Failed, " << CD + MyPrefix + File << endl;
         if (GrabFirst(OrigPath, MyPrefix, Depth++) == true)
            continue;

         return false;
      } else {
         Prefix = MyPrefix;
         return true;
      }
   }
   return false;
}

                                                                        /*}}} */
// IndexCopy::ReconstructChop - Fixes bad source paths                  /*{{{*/
// ---------------------------------------------------------------------
/* This removes path components from the filename and prepends the location
   of the package files until a file is found */
bool IndexCopy::ReconstructChop(unsigned long &Chop, string Dir, string File)
{
   // Attempt to reconstruct the filename
   unsigned long Depth = 0;
   while (1) {
      struct stat Buf;
      if (stat(string(Dir + File).c_str(), &Buf) != 0) {
         File = ChopDirs(File, 1);
         Depth++;
         if (File.empty() == false)
            continue;
         return false;
      } else {
         Chop = Depth;
         return true;
      }
   }
   return false;
}

                                                                        /*}}} */
// IndexCopy::ConvertToSourceList - Convert a Path to a sourcelist      /*{{{*/
// ---------------------------------------------------------------------
/* We look for things in dists/ notation and convert them to 
   <dist> <component> form otherwise it is left alone. This also strips
   the CD path. 
 
   This implements a regex sort of like: 
    (.*)/dists/([^/]*)/(.*)/binary-* 
     ^          ^      ^- Component
     |          |-------- Distribution
     |------------------- Path
   
   It was deciced to use only a single word for dist (rather than say
   unstable/non-us) to increase the chance that each CD gets a single
   line in sources.list.
 */
void IndexCopy::ConvertToSourceList(string CD, string &Path)
{
   char S[300];
   snprintf(S, sizeof(S), "binary-%s",
            _config->Find("Apt::Architecture").c_str());

   // Strip the cdrom base path
   Path = string(Path, CD.length());
   if (Path.empty() == true)
      Path = "/";

   // Too short to be a dists/ type
   if (Path.length() < strlen("dists/"))
      return;

   // Not a dists type.
   if (stringcmp(Path.c_str(), Path.c_str() + strlen("dists/"), "dists/") != 0)
      return;

   // Isolate the dist
   string::size_type Slash = strlen("dists/");
   string::size_type Slash2 = Path.find('/', Slash + 1);
   if (Slash2 == string::npos || Slash2 + 2 >= Path.length())
      return;
   string Dist = string(Path, Slash, Slash2 - Slash);

   // Isolate the component
   Slash = Slash2;
   for (unsigned I = 0; I != 10; I++) {
      Slash = Path.find('/', Slash + 1);
      if (Slash == string::npos || Slash + 2 >= Path.length())
         return;
      string Comp = string(Path, Slash2 + 1, Slash - Slash2 - 1);

      // Verify the trailing binary- bit
      string::size_type BinSlash = Path.find('/', Slash + 1);
      if (Slash == string::npos)
         return;
      string Binary = string(Path, Slash + 1, BinSlash - Slash - 1);

      if (Binary != S && Binary != "source")
         continue;

      Path = Dist + ' ' + Comp;
      return;
   }
}

                                                                        /*}}} */
// IndexCopy::GrabFirst - Return the first Depth path components        /*{{{*/
// ---------------------------------------------------------------------
/* */
bool IndexCopy::GrabFirst(string Path, string &To, unsigned int Depth)
{
   string::size_type I = 0;
   do {
      I = Path.find('/', I + 1);
      Depth--;
   }
   while (I != string::npos && Depth != 0);

   if (I == string::npos)
      return false;

   To = string(Path, 0, I + 1);
   return true;
}

                                                                        /*}}} */
// PackageCopy::GetFile - Get the file information from the section     /*{{{*/
// ---------------------------------------------------------------------
/* */
bool PackageCopy::GetFile(string &File, unsigned long &Size)
{
   File = Section->FindS("Filename");
   Size = Section->FindI("Size");
   if (File.empty() || Size == 0)
      return _error->Error(_("Cannot find filename or size tag"));
   return true;
}

                                                                        /*}}} */
// PackageCopy::RewriteEntry - Rewrite the entry with a new filename    /*{{{*/
// ---------------------------------------------------------------------
/* */
bool PackageCopy::RewriteEntry(FILE *Target, string File)
{
   TFRewriteData Changes[] = { {"Filename", File.c_str()}
   ,
   {}
   };

   if (TFRewrite(Target, *Section, TFRewritePackageOrder, Changes) == false)
      return false;
   fputc('\n', Target);
   return true;
}

                                                                        /*}}} */
// SourceCopy::GetFile - Get the file information from the section      /*{{{*/
// ---------------------------------------------------------------------
/* */
bool SourceCopy::GetFile(string &File, unsigned long &Size)
{
   string Files = Section->FindS("Files");
   if (Files.empty() == true)
      return false;

   // Stash the / terminated directory prefix
   string Base = Section->FindS("Directory");
   if (Base.empty() == false && Base[Base.length() - 1] != '/')
      Base += '/';

   // Read the first file triplet
   const char *C = Files.c_str();
   string sSize;
   string MD5Hash;

   // Parse each of the elements
   if (ParseQuoteWord(C, MD5Hash) == false ||
       ParseQuoteWord(C, sSize) == false || ParseQuoteWord(C, File) == false)
      return _error->Error(_("Error parsing file record"));

   // Parse the size and append the directory
   Size = atoi(sSize.c_str());
   File = Base + File;
   return true;
}

                                                                        /*}}} */
// SourceCopy::RewriteEntry - Rewrite the entry with a new filename     /*{{{*/
// ---------------------------------------------------------------------
/* */
bool SourceCopy::RewriteEntry(FILE *Target, string File)
{
   string Dir(File, 0, File.rfind('/'));
   TFRewriteData Changes[] = { {"Directory", Dir.c_str()}
   ,
   {}
   };

   if (TFRewrite(Target, *Section, TFRewriteSourceOrder, Changes) == false)
      return false;
   fputc('\n', Target);
   return true;
}

                                                                        /*}}} */