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-rw-r--r--kabc/lock.cpp162
1 files changed, 162 insertions, 0 deletions
diff --git a/kabc/lock.cpp b/kabc/lock.cpp
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index 000000000..a3270459d
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+++ 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"