kmail/kmfoldersearch.cpp

/*
    This file is part of KMail, the KDE mail client.
    Copyright (c) 2000 Don Sanders <sanders@kde.org>

    KMail is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.

    KMail is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

//Factor byteswap stuff into one header file

#include <config-kmail.h>
#include "kmfoldersearch.h"
#include "kmfolderimap.h"
#include "kmfoldermgr.h"
#include "kmsearchpattern.h"
#include "kmmsgdict.h"
#include "jobscheduler.h"

#include <kdebug.h>
#include <kde_file.h>
#include <klocale.h>
#include <kconfig.h>
#include <kconfiggroup.h>

#include <assert.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <utime.h>

#include <QFile>
#include <QList>
#include <QPointer>
#include <QFileInfo>
#include <QDir>

#ifdef HAVE_BYTESWAP_H
#include <byteswap.h>
#endif

// We define functions as kmail_swap_NN so that we don't get compile errors
// on platforms where bswap_NN happens to be a function instead of a define.

/* Swap bytes in 32 bit value.  */
#ifndef kmail_swap_32
#ifdef bswap_32
#define kmail_swap_32(x) bswap_32(x)
#else
#define kmail_swap_32(x) \
     ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >>  8) |               \
      (((x) & 0x0000ff00) <<  8) | (((x) & 0x000000ff) << 24))
#endif
#endif // kmail_swap_32

// Current version of the .index.search files
#define IDS_SEARCH_VERSION 1000
// The asterisk at the end is important
#define IDS_SEARCH_HEADER "# KMail-Search-IDs V%d\n*"
#define IDS_SEARCH_HEADER_LEN 30


KMSearch::KMSearch(QObject * parent, const char * name)
    :QObject(parent)
{
  setObjectName( name );
  mRemainingFolders = -1;
  mRecursive = true;
  mRunning = false;
  mRoot = 0;
  mSearchPattern = 0;
  mFoundCount = 0;
  mSearchCount = 0;

  mProcessNextBatchTimer = new QTimer();
  mProcessNextBatchTimer->setSingleShot( true );
  connect(mProcessNextBatchTimer, SIGNAL(timeout()), this, SLOT(slotProcessNextBatch()));
}

KMSearch::~KMSearch()
{
  delete mProcessNextBatchTimer;
  delete mSearchPattern;
}

bool KMSearch::write(const QString &location) const
{
  KConfig config(location);
  KConfigGroup group( &config, "Search Folder" );
  if (mSearchPattern)
    mSearchPattern->writeConfig(group);
  if (mRoot.isNull())
    group.writeEntry("Base", "");
  else
    group.writeEntry("Base", mRoot->idString());
  group.writeEntry("Recursive", recursive());
  return true;
}

bool KMSearch::read(const QString &location)
{
  KConfig config( location );
  KConfigGroup group( &config, "Search Folder" );
  if ( !mSearchPattern )
    mSearchPattern = new KMSearchPattern();
  mSearchPattern->readConfig( group );
  QString rootString = group.readEntry( "Base" );
  mRoot = kmkernel->findFolderById( rootString );
  mRecursive = group.readEntry( "Recursive", false );
  return true;
}

void KMSearch::setSearchPattern(KMSearchPattern *searchPattern)
{
  if ( running() )
    stop();
  if ( mSearchPattern != searchPattern ) {
    delete mSearchPattern;
    mSearchPattern = searchPattern;
  }
}

bool KMSearch::inScope(KMFolder* folder) const
{
  if ( mRoot.isNull() || folder == mRoot ) {
    return true;
  }
  if ( !recursive() ) {
    return false;
  }

  KMFolderDir *rootDir = mRoot->child();
  KMFolderDir *ancestorDir = folder->parent();
  while ( ancestorDir ) {
    if ( ancestorDir == rootDir ) {
      return true;
    }
    ancestorDir = ancestorDir->parent();
  }
  return false;
}

void KMSearch::start()
{
  //close all referenced folders
  QList<QPointer<KMFolder> >::Iterator fit;
  for ( fit = mOpenedFolders.begin(); fit != mOpenedFolders.end(); ++fit ) {
    if ( !(*fit) ) {
      continue;
    }
    (*fit)->close( "kmsearch" );
  }
  mOpenedFolders.clear();
  mFolders.clear();

  if ( running() ) {
    return;
  }

  if ( !mSearchPattern ) {
    emit finished( true );
    return;
  }

  mFoundCount = 0;
  mSearchCount = 0;
  mRunning = true;

  mFolders.append( mRoot );
  if ( recursive() ) {
    //Append all descendants to folders
    KMFolder *folder;
    for ( int i = 0; i < mFolders.size(); i++ ) {
      folder = mFolders[i];
      KMFolderDir *dir = 0;
      if ( folder ) {
        dir = folder->child();
      } else {
        dir = &kmkernel->folderMgr()->dir();
      }
      if ( !dir ) {
        continue;
      }

      QListIterator<KMFolderNode*> it( *dir );
      while ( it.hasNext() ) {
        KMFolderNode *node = it.next();
        if ( !node->isDir() ) {
          KMFolder* kmf = dynamic_cast<KMFolder*>( node );
          if ( kmf ) {
            mFolders.append( kmf );
          }
        }
      }
    }
  }

  mRemainingFolders = mFolders.count();
  mLastFolder.clear();
  mProcessNextBatchTimer->start( 0 );
}

void KMSearch::stop()
{
  if ( !running() ) {
    return;
  }

  mIncompleteFolders.clear();
  QList<QPointer<KMFolder> >::ConstIterator jt;
  for ( jt = mOpenedFolders.begin(); jt != mOpenedFolders.end(); ++jt ) {
    KMFolder *folder = *jt;
    if ( !folder ) {
      continue;
    }
    // explicitly stop jobs for this folder as it will not be closed below
    // when the folder is currently selected
    if ( folder->folderType() == KMFolderTypeImap ) {
      KMAcctImap *account =
        static_cast<KMFolderImap*>( folder->storage() )->account();
      account->ignoreJobsForFolder( folder );
    }
    folder->storage()->search( 0 );
    mSearchCount += folder->count();
    folder->close( "kmsearch" );
  }
  mRemainingFolders = -1;
  mOpenedFolders.clear();
  mFolders.clear();
  mLastFolder.clear();
  mRunning = false;
  emit finished(false);
}

void KMSearch::indexFinished() {
  mRunning = false;
}

void KMSearch::slotProcessNextBatch()
{
  if ( !running() ) {
    return;
  }

  if ( mFolders.count() != 0 ) {
    KMFolder *folder = *( mFolders.begin() );
    mFolders.erase( mFolders.begin() );
    if ( folder ) {
      mLastFolder = folder->label();
      folder->open( "kmsearch" );
      mOpenedFolders.append( folder );
      connect( folder->storage(),
               SIGNAL( searchResult( KMFolder*, QList<quint32>,
                                     const KMSearchPattern*, bool ) ),
               this,
               SLOT( slotSearchFolderResult( KMFolder*, QList<quint32>,
                                             const KMSearchPattern*, bool ) ) );
      folder->storage()->search( mSearchPattern );
    } else {
      --mRemainingFolders;
    }
    mProcessNextBatchTimer->start( 0 );
    return;
  }
}

void KMSearch::slotSearchFolderResult( KMFolder *folder,
                                       QList<quint32> serNums,
                                       const KMSearchPattern *pattern,
                                       bool complete )
{
  if ( pattern != mSearchPattern ) {
    return;
  }
  kDebug(5006) << folder->label()
               << "found" << serNums.count();
  mLastFolder = folder->label();
  QList<quint32>::Iterator it;
  for ( it = serNums.begin(); it != serNums.end(); ++it ) {
    emit found( *it );
    ++mFoundCount;
  }
  if ( complete ) {
    disconnect( folder->storage(),
                SIGNAL( searchResult( KMFolder*, QList<quint32>,
                                      const KMSearchPattern*, bool ) ),
                this,
                SLOT( slotSearchFolderResult( KMFolder*, QList<quint32>,
                                              const KMSearchPattern*, bool ) ) );
    --mRemainingFolders;
    mSearchCount += folder->count();
    folder->close( "kmsearch" );
    mOpenedFolders.removeAll( folder );
    if ( mRemainingFolders <= 0 ) {
      mRemainingFolders = 0;
      mRunning = false;
      mLastFolder.clear();
      mRemainingFolders = -1;
      mFolders.clear();
      emit finished( true );
    }
  }
}

//-----------------------------------------------------------------------------
KMFolderSearch::KMFolderSearch(KMFolder* folder, const char* name)
  : FolderStorage(folder, name)
{
  mIdsStream = 0;
  mSearch = 0;
  mInvalid = false;
  mUnlinked = true;
  mTempOpened = false;
  setNoChildren(true);

  //Hook up some slots for live updating of search folders
  //TODO: Optimize folderInvalidated, folderAdded, folderRemoved
  connect(kmkernel->folderMgr(), SIGNAL(msgAdded(KMFolder*, quint32)),
          this, SLOT(examineAddedMessage(KMFolder*, quint32)));
  connect(kmkernel->folderMgr(), SIGNAL(msgRemoved(KMFolder*, quint32)),
          this, SLOT(examineRemovedMessage(KMFolder*, quint32)));
  connect(kmkernel->folderMgr(), SIGNAL(msgChanged(KMFolder*, quint32, int)),
          this, SLOT(examineChangedMessage(KMFolder*, quint32, int)));
  connect(kmkernel->folderMgr(), SIGNAL(folderInvalidated(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->folderMgr(), SIGNAL(folderAdded(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->folderMgr(), SIGNAL(folderRemoved(KMFolder*)),
          this, SLOT(examineRemovedFolder(KMFolder*)));
  connect(kmkernel->folderMgr(), SIGNAL(msgHeaderChanged(KMFolder*,int)),
          this, SLOT(propagateHeaderChanged(KMFolder*,int)));

  connect(kmkernel->imapFolderMgr(), SIGNAL(msgAdded(KMFolder*, quint32)),
          this, SLOT(examineAddedMessage(KMFolder*, quint32)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(msgRemoved(KMFolder*, quint32)),
          this, SLOT(examineRemovedMessage(KMFolder*, quint32)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(msgChanged(KMFolder*, quint32, int)),
          this, SLOT(examineChangedMessage(KMFolder*, quint32, int)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(folderInvalidated(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(folderAdded(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(folderRemoved(KMFolder*)),
          this, SLOT(examineRemovedFolder(KMFolder*)));
  connect(kmkernel->imapFolderMgr(), SIGNAL(msgHeaderChanged(KMFolder*,int)),
          this, SLOT(propagateHeaderChanged(KMFolder*,int)));

  connect(kmkernel->dimapFolderMgr(), SIGNAL(msgAdded(KMFolder*, quint32)),
          this, SLOT(examineAddedMessage(KMFolder*, quint32)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(msgRemoved(KMFolder*, quint32)),
          this, SLOT(examineRemovedMessage(KMFolder*, quint32)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(msgChanged(KMFolder*, quint32, int)),
          this, SLOT(examineChangedMessage(KMFolder*, quint32, int)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(folderInvalidated(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(folderAdded(KMFolder*)),
          this, SLOT(examineInvalidatedFolder(KMFolder*)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(folderRemoved(KMFolder*)),
          this, SLOT(examineRemovedFolder(KMFolder*)));
  connect(kmkernel->dimapFolderMgr(), SIGNAL(msgHeaderChanged(KMFolder*,int)),
          this, SLOT(propagateHeaderChanged(KMFolder*,int)));

  mExecuteSearchTimer = new QTimer();
  mExecuteSearchTimer->setSingleShot( true );
  connect(mExecuteSearchTimer, SIGNAL(timeout()),
          this, SLOT(executeSearch()));
}

KMFolderSearch::~KMFolderSearch()
{
  delete mExecuteSearchTimer;
  delete mSearch;
  mSearch = 0;
  if ( mOpenCount > 0 ) {
    close( "~foldersearch", true );
  }
}

void KMFolderSearch::setSearch( KMSearch *search )
{
  truncateIndex(); //new search old index is obsolete
  emit cleared();
  mInvalid = false;
  setDirty( true ); //have to write the index
  if ( !mUnlinked ) {
    unlink( QFile::encodeName( indexLocation() ) );
    mUnlinked = true;
  }
  if ( mSearch != search ) {
    mSearch->stop();
    delete mSearch;
    mSearch = search; // take ownership
    if ( mSearch ) {
      QObject::connect( search, SIGNAL( found( quint32 ) ),
                        SLOT( addSerNum( quint32 ) ) );
      QObject::connect( search, SIGNAL( finished( bool ) ),
                        SLOT( searchFinished( bool ) ) );
    }
  }
  if ( mSearch ) {
    mSearch->write( location() );
  }
  clearIndex();
  mTotalMsgs = 0;
  mUnreadMsgs = 0;
  emit numUnreadMsgsChanged( folder() );
  emit changed(); // really want a kmfolder cleared signal
  /* TODO There is KMFolder::cleared signal now. Adjust. */
  if ( mSearch ) {
    mSearch->start();
  }
  open( "foldersearch" ); // will be closed in searchFinished
}

void KMFolderSearch::executeSearch()
{
  if ( mSearch ) {
    mSearch->stop();
  }
  setSearch( mSearch );
  invalidateFolder();
}

const KMSearch* KMFolderSearch::search() const
{
  return mSearch;
}

void KMFolderSearch::searchFinished( bool success )
{
  if ( !success) {
    mSerNums.clear();
  }
  close( "foldersearch" );
}

void KMFolderSearch::addSerNum( quint32 serNum )
{
  if ( mInvalid ) {
    // A new search is scheduled don't bother doing anything
    return;
  }
  int idx = -1;
  KMFolder *aFolder = 0;
  KMMsgDict::instance()->getLocation( serNum, &aFolder, &idx );
  // warn instead of assert() because of
  // https://intevation.de/roundup/kolab/issue2216
  if ( !aFolder || ( idx == -1 ) ) {
    kDebug(5006) << "Not adding message with serNum" << serNum
                 << ": folder is" << aFolder << ", index is" << idx;
    return;
  }
  if ( mFolders.indexOf( aFolder ) == -1 ) {
    aFolder->open( "foldersearch" );
    mFolders.append( aFolder );
  }
  setDirty( true ); //TODO append a single entry to .ids file and sync.
  if ( !mUnlinked ) {
    unlink( QFile::encodeName( indexLocation() ) );
    mUnlinked = true;
  }
  mSerNums.append( serNum );
  KMMsgBase *mb = aFolder->getMsgBase( idx );
  if ( mb && ( mb->status().isUnread() || mb->status().isNew() ) ) {
    if ( mUnreadMsgs == -1 ) {
      mUnreadMsgs = 0;
    }
    ++mUnreadMsgs;
    emit numUnreadMsgsChanged( folder() );
  }
  emitMsgAddedSignals( mSerNums.count() - 1 );
}

void KMFolderSearch::removeSerNum( quint32 serNum )
{
  QVector<quint32>::const_iterator it;
  int i = 0;
  for( it = mSerNums.begin(); it != mSerNums.end(); ++it, ++i )
    if ( (*it) == serNum ) {
      int idx = -1;
      KMFolder *aFolder = 0;
      KMMsgDict::instance()->getLocation( serNum, &aFolder, &idx );
      assert( aFolder && ( idx != -1 ) );
      emit msgRemoved( folder(), serNum );
      removeMsg( i );
      return;
    }
  if ( !mUnlinked ) {
    unlink( QFile::encodeName( indexLocation() ) );
    mUnlinked = true;
  }
}

int KMFolderSearch::addMsg( KMMessage*, int* index_return )
{
  //Not supported search folder can't own messages
  *index_return = -1;
  return 0;
}

bool KMFolderSearch::readSearch()
{
  mSearch = new KMSearch;
  QObject::connect( mSearch, SIGNAL(found(quint32)), SLOT(addSerNum(quint32)) );
  QObject::connect( mSearch, SIGNAL(finished(bool)), SLOT(searchFinished(bool)) );
  return mSearch->read( location() );
}

int KMFolderSearch::open( const char * )
{
  mOpenCount++;
  kmkernel->jobScheduler()->notifyOpeningFolder( folder() );
  if ( mOpenCount > 1 ) {
        return 0;  // already open
  }

  readConfig();
  if ( !mSearch && !readSearch() ) {
    return -1;
  }

  emit cleared();
  if ( !mSearch || !search()->running() ) {
    if ( !readIndex() ) {
      executeSearch();
    }
  }

  return 0;
}

bool KMFolderSearch::canAccess() const
{
  assert( !folder()->name().isEmpty() );

  QFileInfo finfo( location() );
  return finfo.isDir() && finfo.isReadable() && finfo.isWritable();
}

void KMFolderSearch::sync()
{
  if ( mDirty ) {
    if (mSearch)
      mSearch->write( location() );
    updateIndex();
  }
}

void KMFolderSearch::close( const char *, bool force )
{
  if ( mOpenCount <= 0 ) {
    return;
  }
  if ( mOpenCount > 0 ) {
    mOpenCount--;
  }
  if ( mOpenCount > 0 && !force ) {
    return;
  }

  if ( mAutoCreateIndex ) {
    if ( mSearch ) {
      mSearch->write(location());
    }
    updateIndex();
    if ( mSearch && search()->running() ) {
      mSearch->stop();
    }
    writeConfig();
  }

  //close all referenced folders
  QList<QPointer<KMFolder> >::ConstIterator fit;
  for ( fit = mFolders.begin(); fit != mFolders.end(); ++fit ) {
    if ( !(*fit) ) {
      continue;
    }
    (*fit)->close( "foldersearch" );
  }
  mFolders.clear();

  clearIndex( true );

  if ( mIdsStream ) {
    fclose( mIdsStream );
  }

  mOpenCount   = 0;
  mIdsStream = 0;
  mUnreadMsgs  = -1;
}

int KMFolderSearch::create()
{
  int old_umask;
  int rc = unlink( QFile::encodeName( location() ) );
  if ( !rc ) {
    return rc;
  }
  rc = 0;

  assert( !folder()->name().isEmpty() );
  assert( mOpenCount == 0 );

  kDebug(5006) <<"Creating folder" << location();
  if ( access( QFile::encodeName( location() ), F_OK ) == 0 ) {
    kDebug(5006) << "Call to access function failed.";
    return EEXIST;
  }

  old_umask = umask( 077 );
  FILE *mStream = KDE_fopen( QFile::encodeName( location() ), "w+" );
  umask( old_umask );
  if ( !mStream ) {
    return errno;
  }
  fclose( mStream );

  clearIndex();
  if ( !mSearch ) {
    mSearch = new KMSearch();
    QObject::connect( mSearch, SIGNAL( found( quint32 ) ),
                      SLOT( addSerNum( quint32 ) ) );
    QObject::connect( mSearch, SIGNAL( finished( bool ) ),
                      SLOT( searchFinished( bool ) ) );
    }
  mSearch->write( location() );
  mOpenCount++;
  mChanged = false;
  mUnreadMsgs = 0;
  mTotalMsgs = 0;
  return rc;
}

int KMFolderSearch::compact( bool )
{
  needsCompact = false;
  return 0;
}

bool KMFolderSearch::isReadOnly() const
{
  return false; //TODO: Make it true and get that working ok
}

FolderJob* KMFolderSearch::doCreateJob( KMMessage*, FolderJob::JobType,
                                        KMFolder*, const QString&,
                                        const AttachmentStrategy* ) const
{
  // Should never be called
  assert( 0 );
  return 0;
}

FolderJob* KMFolderSearch::doCreateJob( QList<KMMessage*>&, const QString&,
                                        FolderJob::JobType, KMFolder* ) const
{
  // Should never be called
  assert( 0 );
  return 0;
}

const KMMsgBase* KMFolderSearch::getMsgBase( int idx ) const
{
  int folderIdx = -1;
  KMFolder *folder = 0;
  if ( idx < 0 || (qint32)idx >= mSerNums.count() )
    return 0;
  KMMsgDict::instance()->getLocation( mSerNums[idx], &folder, &folderIdx );
  assert( folder && ( folderIdx != -1 ) );
  return folder->getMsgBase( folderIdx );
}

KMMsgBase* KMFolderSearch::getMsgBase( int idx )
{
  int folderIdx = -1;
  KMFolder *folder = 0;
  if ( idx < 0 || (qint32)idx >= mSerNums.count() )
    return 0;
  KMMsgDict::instance()->getLocation( mSerNums[idx], &folder, &folderIdx );
  if ( !folder || folderIdx == -1 )
    return 0; //exceptional case
  return folder->getMsgBase( folderIdx );
}

//-----------------------------------------------------------------------------
KMMessage* KMFolderSearch::getMsg( int idx )
{
  int folderIdx = -1;
  KMFolder *folder = 0;
  if ( idx < 0 || (qint32)idx >= mSerNums.count() )
    return 0;
  KMMsgDict::instance()->getLocation(mSerNums[idx], &folder, &folderIdx);
  assert( folder && ( folderIdx != -1 ) );
  KMMessage* msg = folder->getMsg( folderIdx );
  return msg;
}

//-------------------------------------------------------------
void
KMFolderSearch::ignoreJobsForMessage( KMMessage* msg )
{
  if ( !msg || msg->transferInProgress() )
    return;
  /* While non-imap folders manage their jobs themselves, imap ones let
     their account manage them. Therefor first clear the jobs managed by
     this folder via the inherited method, then clear the imap ones. */
  FolderStorage::ignoreJobsForMessage( msg );

  if ( msg->parent()->folderType() == KMFolderTypeImap ) {
    KMAcctImap *account =
        static_cast<KMFolderImap*>( msg->storage() )->account();
    if( !account )
      return;
    account->ignoreJobsForMessage( msg );
  }
}


int KMFolderSearch::find( const KMMsgBase* msg ) const
{
  int pos = 0;
  quint32 serNum = msg->getMsgSerNum();
  QVector<quint32>::const_iterator it;
  for( it = mSerNums.begin(); it != mSerNums.end(); ++it ) {
    if ( (*it) == serNum )
      return pos;
    ++pos;
  }
  return -1;
}

QString KMFolderSearch::indexLocation() const
{
  QString sLocation(folder()->path());

  if ( !sLocation.isEmpty() )
    sLocation += '/';
  sLocation += '.';
  sLocation += dotEscape( fileName() );
  sLocation += ".index";
  sLocation += ".search";

  return sLocation;
}

int KMFolderSearch::updateIndex()
{
  if ( mSearch && search()->running() )
    unlink( QFile::encodeName( indexLocation() ) );
  else if ( dirty() )
    return writeIndex();
  return 0;
}

int KMFolderSearch::writeIndex( bool )
{
  // TODO:If we fail to write the index we should panic the kernel
  // TODO:and the same for other folder types too, and the msgDict.
  QString filename = indexLocation();
  int old_umask = umask( 077 );
  QString tempName = filename + ".temp";
  unlink( QFile::encodeName( tempName ) );

  // We touch the folder, otherwise the index is regenerated, if KMail is
  // running, while the clock switches from daylight savings time to normal time
  utime( QFile::encodeName( QDir::toNativeSeparators(location()) ), 0 );

  FILE *tmpIndexStream = KDE_fopen( QFile::encodeName( tempName ), "w" );
  umask( old_umask );

  if ( !tmpIndexStream ) {
    kDebug(5006) << "Cannot write '" << filename
                 << strerror( errno ) << "(" << errno << ")";
    truncate( QFile::encodeName( filename ), 0 );
    return -1;
  }
  fprintf( tmpIndexStream, IDS_SEARCH_HEADER, IDS_SEARCH_VERSION );
  quint32 byteOrder = 0x12345678;
  fwrite( &byteOrder, sizeof( byteOrder ), 1, tmpIndexStream );

  quint32 count = mSerNums.count();
  if ( !fwrite( &count, sizeof( count ), 1, tmpIndexStream ) ) {
    fclose( tmpIndexStream );
    truncate( QFile::encodeName( filename ), 0 );
    return -1;
  }

  QVector<quint32>::iterator it;
  for( it = mSerNums.begin(); it != mSerNums.end(); ++it ) {
    quint32 serNum = *it;
    if ( !fwrite( &serNum, sizeof( serNum ), 1, tmpIndexStream ) )
      return -1;
  }
  if ( ferror( tmpIndexStream ) ) return ferror( tmpIndexStream );
  if ( fflush( tmpIndexStream ) != 0 ) return errno;
  if ( fsync( fileno(tmpIndexStream ) ) != 0) return errno;
  if ( fclose( tmpIndexStream ) != 0 ) return errno;

  KDE_rename( QFile::encodeName( tempName ),
              QFile::encodeName( indexLocation() ) );
  mDirty = false;
  mUnlinked = false;

  return 0;
}

DwString KMFolderSearch::getDwString(int idx)
{
  return getMsgBase(idx)->parent()->getDwString( idx );
}

KMMessage* KMFolderSearch::readMsg(int idx)
{
  int folderIdx = -1;
  KMFolder *folder = 0;
  KMMsgDict::instance()->getLocation( mSerNums[idx], &folder, &folderIdx );
  assert( folder && ( folderIdx != -1 ) );
  return folder->getMsg( folderIdx );
}

bool KMFolderSearch::readIndex()
{
  clearIndex();
  QString filename = indexLocation();
  mIdsStream = KDE_fopen( QFile::encodeName( filename ), "r+" );
  if ( !mIdsStream ) {
    return false;
  }

  int version = 0;
  fscanf( mIdsStream, IDS_SEARCH_HEADER, &version );
  if ( version != IDS_SEARCH_VERSION ) {
    fclose( mIdsStream );
    mIdsStream = 0;
    return false;
  }
  bool swapByteOrder;
  quint32 byte_order;
  if ( !fread( &byte_order, sizeof(byte_order), 1, mIdsStream ) ) {
    fclose( mIdsStream );
    mIdsStream = 0;
    return false;
  }
  swapByteOrder = (byte_order == 0x78563412);

  quint32 count;
  if ( !fread( &count, sizeof(count), 1, mIdsStream  )) {
    fclose( mIdsStream );
    mIdsStream = 0;
    return false;
  }
  if ( swapByteOrder ) {
    count = kmail_swap_32( count );
  }

  mUnreadMsgs = 0;
  mSerNums.reserve( count );
  for ( unsigned int index = 0; index < count; index++ ) {
    quint32 serNum;
    int folderIdx = -1;
    KMFolder *folder = 0;
    bool readOk = fread( &serNum, sizeof(serNum), 1, mIdsStream );
    if ( !readOk ) {
      clearIndex();
      fclose( mIdsStream );
      mIdsStream = 0;
      return false;
    }
    if ( swapByteOrder ) {
      serNum = kmail_swap_32( serNum );
    }

    KMMsgDict::instance()->getLocation( serNum, &folder, &folderIdx );
    if ( !folder || ( folderIdx == -1 ) ) {
      clearIndex();
      fclose( mIdsStream );
      mIdsStream = 0;
      return false;
    }
    mSerNums.push_back( serNum );
    if ( mFolders.indexOf( folder ) == -1 ) {
      if ( mInvalid ) //exceptional case for when folder has invalid ids
        return false;
      folder->open( "foldersearch" );
      mFolders.append( folder );
    }
    KMMsgBase *mb = folder->getMsgBase( folderIdx );
    if (!mb) {  //Exceptional case our .ids file is messed up
      return false;
    }
    if ( mb->status().isNew() || mb->status().isUnread() ) {
      if ( mUnreadMsgs == -1 ) {
        ++mUnreadMsgs;
      }
      ++mUnreadMsgs;
    }
  }
  mTotalMsgs = mSerNums.count();
  fclose( mIdsStream );
  mIdsStream = 0;
  mUnlinked = true;
  return true;
}

int KMFolderSearch::removeContents()
{
  unlink( QFile::encodeName( location() ) );
  unlink( QFile::encodeName( indexLocation() ) );
  mUnlinked = true;
  return 0;
}

int KMFolderSearch::expungeContents()
{
  setSearch(new KMSearch());
  return 0;
}

int KMFolderSearch::count(bool cache) const
{
  Q_UNUSED(cache);
  return mSerNums.count();
}

KMMsgBase* KMFolderSearch::takeIndexEntry(int idx)
{
  assert(idx >= 0 && idx < (int)mSerNums.count());
  KMMsgBase *msgBase = getMsgBase(idx);
  QVector<quint32>::iterator it = mSerNums.begin();
  mSerNums.erase(&it[idx]);
  return msgBase;
}

KMMsgInfo* KMFolderSearch::setIndexEntry( int idx, KMMessage *msg )
{
  assert( idx >= 0 && idx < (int)mSerNums.count() );
  Q_UNUSED( idx );
  return msg->storage()->setIndexEntry( msg->parent()->find( msg ), msg );
}

void KMFolderSearch::clearIndex( bool, bool )
{
  //close all referenced folders
  QList<QPointer<KMFolder> >::Iterator fit;
  for ( fit = mFolders.begin(); fit != mFolders.end(); ++fit ) {
    if ( !(*fit) ) {
      continue;
    }
    (*fit)->close( "foldersearch" );
  }
  mFolders.clear();

  mSerNums.clear();
}

void KMFolderSearch::truncateIndex()
{
  truncate( QFile::encodeName( indexLocation() ), IDS_SEARCH_HEADER_LEN );
}

void KMFolderSearch::examineAddedMessage( KMFolder *aFolder, quint32 serNum )
{
  if ( !search() && !readSearch() ) {
    return;
  }
  if ( !search()->inScope( aFolder ) ) {
    return;
  }
  if ( !mTempOpened ) {
    open( "foldersearch" );
    mTempOpened = true;
  }

  if ( !search()->searchPattern() ) {
    return;
  }

  int idx = -1;
  KMFolder *folder = 0;
  KMMsgDict::instance()->getLocation( serNum, &folder, &idx );
  assert( folder && (idx != -1) );
  assert( folder == aFolder );
  KMFolderOpener openFolder( folder, "examineAddedMessage" );

  // if we are already checking this folder, refcount
  if ( mFoldersCurrentlyBeingSearched.contains( folder ) ) {
    unsigned int count = mFoldersCurrentlyBeingSearched[folder];
    mFoldersCurrentlyBeingSearched.insert( folder, count+1 );
  } else {
    connect( folder->storage(),
             SIGNAL( searchDone( KMFolder*, quint32,
                                 const KMSearchPattern*, bool ) ),
             this,
             SLOT( slotSearchExamineMsgDone( KMFolder*, quint32,
                                             const KMSearchPattern*, bool ) ) );
    mFoldersCurrentlyBeingSearched.insert( folder, 1 );
  }
  folder->storage()->search( search()->searchPattern(), serNum );
}

void KMFolderSearch::slotSearchExamineMsgDone( KMFolder* folder,
                                               quint32 serNum,
                                               const KMSearchPattern *pattern,
                                               bool matches )
{
  if ( search()->searchPattern() != pattern ) {
    return;
  }
  KMFolderOpener openFolder( folder, "SearchExamineMsgDone" );
  kDebug(5006) << folder->label() <<": serNum" << serNum
               << "matches?" << matches;

  Q_ASSERT( mFoldersCurrentlyBeingSearched.contains( folder ) );

  unsigned int count = mFoldersCurrentlyBeingSearched[folder];
  if ( count == 1 ) {
    disconnect( folder->storage(),
                  SIGNAL( searchDone( KMFolder*, quint32,
                                      const KMSearchPattern*, bool ) ),
                  this,
                  SLOT( slotSearchExamineMsgDone( KMFolder*, quint32,
                                                  const KMSearchPattern*, bool ) ) );
      mFoldersCurrentlyBeingSearched.remove( folder );
    } else {
      mFoldersCurrentlyBeingSearched.insert( folder, count-1 );
    }

  if ( !matches ) {
    QVector<quint32>::const_iterator it;
    it = qFind( mSerNums.begin(), mSerNums.end(), serNum );
    if ( it != mSerNums.end() ) {
      removeSerNum( serNum );
    }
    return;
  }

  QVector<quint32>::const_iterator it;
  it = qFind( mSerNums.begin(), mSerNums.end(), serNum );
  if ( it == mSerNums.end() ) {
    addSerNum( serNum );
  }
}

void KMFolderSearch::examineRemovedMessage( KMFolder *folder, quint32 serNum )
{
  if ( !search() && !readSearch() ) {
    return;
  }
  if ( !search()->inScope( folder ) ) {
    return;
  }
  if ( !mTempOpened ) {
    open( "foldersearch" );
    mTempOpened = true;
  }

  if ( mSearch->running() ) {
    mExecuteSearchTimer->start( 0 );
  } else {
    removeSerNum( serNum );
  }
}

void KMFolderSearch::examineChangedMessage( KMFolder *aFolder,
                                            quint32 serNum, int delta )
{
  if ( !search() && !readSearch() ) {
    return;
  }
  if ( !search()->inScope( aFolder ) ) {
    return;
  }
  if ( !mTempOpened ) {
    open( "foldersearch" );
    mTempOpened = true;
  }
  QVector<quint32>::const_iterator it;
  it = qFind( mSerNums.begin(), mSerNums.end(), serNum );
  if ( it != mSerNums.end() ) {
    mUnreadMsgs += delta;
    emit numUnreadMsgsChanged( folder() );
    emit msgChanged( folder(), serNum, delta );
  }
}

void KMFolderSearch::examineInvalidatedFolder( KMFolder *folder )
{
  if ( !search() && !readSearch() ) {
    return;
  }
  if ( !search()->inScope( folder ) ) {
    return;
  }
  if ( mTempOpened ) {
    close( "foldersearch" );
    mTempOpened = false;
  }

  mInvalid = true;
  if ( mSearch ) {
    mSearch->stop();
  }

  if ( !mUnlinked ) {
    unlink( QFile::encodeName( indexLocation() ) );
    mUnlinked = true;
  }

  if ( !isOpened() ) { //give up, until the user manually opens the folder
    return;
  }

  if ( !mTempOpened ) {
    open( "foldersearch" );
    mTempOpened = true;
  }
  mExecuteSearchTimer->start( 0 );
}

void KMFolderSearch::examineRemovedFolder( KMFolder *folder )
{
  examineInvalidatedFolder( folder );
  if ( mSearch->root() == folder ) {
    delete mSearch;
    mSearch = 0;
  }
}

void KMFolderSearch::propagateHeaderChanged( KMFolder *aFolder, int idx )
{
  int pos = 0;
  if ( !search() && !readSearch() ) {
    return;
  }
  if ( !search()->inScope( aFolder ) ) {
    return;
  }
  if ( !mTempOpened ) {
    open( "foldersearch" );
    mTempOpened = true;
  }

  quint32 serNum = KMMsgDict::instance()->getMsgSerNum( aFolder, idx );
  QVector<quint32>::const_iterator it;
  for( it = mSerNums.begin(); it != mSerNums.end(); ++it ) {
    if ( (*it) == serNum ) {
      emit msgHeaderChanged( folder(), pos );
      break;
    }
    ++pos;
  }
  // let's try if the message matches our search
  KMFolderOpener openAFolder( aFolder, "foldersearch" );

  // if we are already checking this folder, refcount
  if ( mFoldersCurrentlyBeingSearched.contains( aFolder ) ) {
    unsigned int count = mFoldersCurrentlyBeingSearched[aFolder];
    mFoldersCurrentlyBeingSearched.insert( aFolder, count+1 );
  } else {
    connect( aFolder->storage(),
             SIGNAL( searchDone( KMFolder*, quint32,
                                 const KMSearchPattern*, bool ) ),
             this,
             SLOT( slotSearchExamineMsgDone( KMFolder*, quint32,
                                             const KMSearchPattern*, bool ) ) );
    mFoldersCurrentlyBeingSearched.insert( aFolder, 1 );
  }
  aFolder->storage()->search( search()->searchPattern(), serNum );
}

void KMFolderSearch::tryReleasingFolder(KMFolder* folder)
{
  // We'll succeed releasing the folder only if mTempOpened and mOpenCount==1.
  // Otherwise if mOpenCount>1 (e.g while the search dialog is up), we would just keep closing/reopening for nothing
  if ( mTempOpened && mOpenCount == 1 )
  {
    examineInvalidatedFolder( folder );
  }
}

#include "kmfoldersearch.moc"