1 files changed, 162 insertions, 0 deletions
diff --git a/kabc/lock.cpp b/kabc/lock.cpp
new file mode 100644
index 000000000..a3270459d
--- /dev/null
+++ b/kabc/lock.cpp
@@ -0,0 +1,162 @@
+/*
+    This file is part of libkabc.
+    Copyright (c) 2001,2003 Cornelius Schumacher <schumacher@kde.org>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library 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
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA 02110-1301, USA.
+*/
+
+#include "lock.h"
+
+#include <kapplication.h>
+#include <kdebug.h>
+#include <klocale.h>
+#include <kstandarddirs.h>
+#include <ktempfile.h>
+
+#include <qfile.h>
+
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+using namespace KABC;
+
+Lock::Lock( const QString &identifier )
+  : mIdentifier( identifier )
+{
+  mIdentifier.replace( "/", "_" );
+}
+
+Lock::~Lock()
+{
+  unlock();
+}
+
+QString Lock::locksDir()
+{
+  return locateLocal( "data", "kabc/lock/" );
+}
+
+bool Lock::readLockFile( const QString &filename, int &pid, QString &app )
+{
+  QFile file( filename );
+  if ( !file.open( IO_ReadOnly ) ) return false;
+
+  QTextStream t( &file );
+  pid = t.readLine().toInt();
+  app = t.readLine();
+
+  return true;
+}
+
+bool Lock::writeLockFile( const QString &filename )
+{
+  QFile file( filename );
+  if ( !file.open( IO_WriteOnly ) ) return false;
+  QTextStream t( &file );
+  t << ::getpid() << endl << QString( KGlobal::instance()->instanceName() );
+
+  return true;
+}
+
+QString Lock::lockFileName() const
+{
+  return locksDir() + mIdentifier + ".lock";
+}
+
+bool Lock::lock()
+{
+  kdDebug(5700) << "Lock::lock()" << endl;
+
+  QString lockName = lockFileName();
+  kdDebug(5700) << "-- lock name: " << lockName << endl;
+
+  if ( QFile::exists( lockName ) ) {  // check if it is a stale lock file
+    int pid;
+    QString app;
+
+    if ( !readLockFile( lockFileName(), pid, app ) ) {
+      mError = i18n("Unable to open lock file.");
+      return false;
+    }
+
+    int retval = ::kill( pid, 0 );
+    if ( retval == -1 && errno == ESRCH ) { // process doesn't exists anymore
+      QFile::remove( lockName );
+      kdWarning(5700) << "Removed stale lock file from process '" << app << "'"
+                      << endl;
+    } else {
+      QString identifier( mIdentifier );
+      identifier.replace( '_', '/' );
+
+      mError = i18n("The address book '%1' is locked by application '%2'.\nIf you believe this is incorrect, just remove the lock file from '%3'")
+               .arg( identifier ).arg( app ).arg( locateLocal( "data", "kabc/lock/*.lock" ) );
+      return false;
+    }
+  }
+
+  QString lockUniqueName;
+  lockUniqueName = mIdentifier + kapp->randomString( 8 );
+  mLockUniqueName = locateLocal( "data", "kabc/lock/" + lockUniqueName );
+  kdDebug(5700) << "-- lock unique name: " << mLockUniqueName << endl;
+
+  // Create unique file
+  writeLockFile( mLockUniqueName );
+
+  // Create lock file
+  int result = ::link( QFile::encodeName( mLockUniqueName ),
+                       QFile::encodeName( lockName ) );
+
+  if ( result == 0 ) {
+    mError = "";
+    emit locked();
+    return true;
+  }
+
+  // TODO: check stat
+
+  mError = i18n("Error");
+  return false;
+}
+
+bool Lock::unlock()
+{
+  int pid;
+  QString app;
+  if ( readLockFile( lockFileName(), pid, app ) ) {
+    if ( pid == getpid() ) {
+      QFile::remove( lockFileName() );
+      QFile::remove( mLockUniqueName );
+      emit unlocked();
+    } else {
+      mError = i18n("Unlock failed. Lock file is owned by other process: %1 (%2)")
+               .arg( app ).arg( QString::number( pid ) );
+      kdDebug() << "Lock::unlock(): " << mError << endl;
+      return false;
+    }
+  }
+
+  mError = "";
+  return true;
+}
+
+QString Lock::error() const
+{
+  return mError;
+}
+
+#include "lock.moc"